diff options
39 files changed, 12178 insertions, 0 deletions
diff --git a/fs/Kconfig b/fs/Kconfig index bec8afa5704d..3a32f3f97e9b 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -1831,6 +1831,7 @@ source "fs/partitions/Kconfig" endmenu source "fs/nls/Kconfig" +source "fs/dlm/Kconfig" endmenu diff --git a/fs/Makefile b/fs/Makefile index 0922727732c5..b298f4fdc6f2 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_SYSFS) += sysfs/ obj-y += devpts/ obj-$(CONFIG_PROFILING) += dcookies.o +obj-$(CONFIG_DLM) += dlm/ # Do not add any filesystems before this line obj-$(CONFIG_REISERFS_FS) += reiserfs/ diff --git a/fs/dlm/Kconfig b/fs/dlm/Kconfig new file mode 100644 index 000000000000..d01f735e6e06 --- /dev/null +++ b/fs/dlm/Kconfig @@ -0,0 +1,30 @@ +menu "Distributed Lock Manager" + depends on INET && EXPERIMENTAL + +config DLM + tristate "Distributed Lock Manager (DLM)" + depends on SYSFS + depends on IPV6 || IPV6=n + select IP_SCTP + select CONFIGFS_FS + help + A general purpose distributed lock manager for kernel or userspace + applications. + +config DLM_DEVICE + tristate "DLM device for userspace access" + depends on DLM + help + This module creates a misc device through which the dlm lockspace + and locking functions become available to userspace applications + (usually through the libdlm library). + +config DLM_DEBUG + bool "DLM debugging" + depends on DLM + help + Under the debugfs mount point, the name of each lockspace will + appear as a file in the "dlm" directory. The output is the + list of resource and locks the local node knows about. + +endmenu diff --git a/fs/dlm/Makefile b/fs/dlm/Makefile new file mode 100644 index 000000000000..1e6232e7d8e5 --- /dev/null +++ b/fs/dlm/Makefile @@ -0,0 +1,21 @@ +obj-$(CONFIG_DLM) += dlm.o +obj-$(CONFIG_DLM_DEVICE) += dlm_device.o + +dlm-y := ast.o \ + config.o \ + dir.o \ + lock.o \ + lockspace.o \ + lowcomms.o \ + main.o \ + member.o \ + memory.o \ + midcomms.o \ + rcom.o \ + recover.o \ + recoverd.o \ + requestqueue.o \ + util.o +dlm-$(CONFIG_DLM_DEBUG) += debug_fs.o + +dlm_device-y := device.o diff --git a/fs/dlm/ast.c b/fs/dlm/ast.c new file mode 100644 index 000000000000..2bd1c5e1a72c --- /dev/null +++ b/fs/dlm/ast.c @@ -0,0 +1,167 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lock.h" +#include "ast.h" + +#define WAKE_ASTS 0 + +static struct list_head ast_queue; +static spinlock_t ast_queue_lock; +static struct task_struct * astd_task; +static unsigned long astd_wakeflags; +static struct semaphore astd_running; + + +void dlm_del_ast(struct dlm_lkb *lkb) +{ + spin_lock(&ast_queue_lock); + if (lkb->lkb_ast_type & (AST_COMP | AST_BAST)) + list_del(&lkb->lkb_astqueue); + spin_unlock(&ast_queue_lock); +} + +void dlm_add_ast(struct dlm_lkb *lkb, int type) +{ + spin_lock(&ast_queue_lock); + if (!(lkb->lkb_ast_type & (AST_COMP | AST_BAST))) { + kref_get(&lkb->lkb_ref); + list_add_tail(&lkb->lkb_astqueue, &ast_queue); + } + lkb->lkb_ast_type |= type; + spin_unlock(&ast_queue_lock); + + set_bit(WAKE_ASTS, &astd_wakeflags); + wake_up_process(astd_task); +} + +static void process_asts(void) +{ + struct dlm_ls *ls = NULL; + struct dlm_rsb *r = NULL; + struct dlm_lkb *lkb; + void (*cast) (long param); + void (*bast) (long param, int mode); + int type = 0, found, bmode; + + for (;;) { + found = FALSE; + spin_lock(&ast_queue_lock); + list_for_each_entry(lkb, &ast_queue, lkb_astqueue) { + r = lkb->lkb_resource; + ls = r->res_ls; + + if (dlm_locking_stopped(ls)) + continue; + + list_del(&lkb->lkb_astqueue); + type = lkb->lkb_ast_type; + lkb->lkb_ast_type = 0; + found = TRUE; + break; + } + spin_unlock(&ast_queue_lock); + + if (!found) + break; + + cast = lkb->lkb_astaddr; + bast = lkb->lkb_bastaddr; + bmode = lkb->lkb_bastmode; + + if ((type & AST_COMP) && cast) + cast(lkb->lkb_astparam); + + /* FIXME: Is it safe to look at lkb_grmode here + without doing a lock_rsb() ? + Look at other checks in v1 to avoid basts. */ + + if ((type & AST_BAST) && bast) + if (!dlm_modes_compat(lkb->lkb_grmode, bmode)) + bast(lkb->lkb_astparam, bmode); + + /* this removes the reference added by dlm_add_ast + and may result in the lkb being freed */ + dlm_put_lkb(lkb); + + schedule(); + } +} + +static inline int no_asts(void) +{ + int ret; + + spin_lock(&ast_queue_lock); + ret = list_empty(&ast_queue); + spin_unlock(&ast_queue_lock); + return ret; +} + +static int dlm_astd(void *data) +{ + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + if (!test_bit(WAKE_ASTS, &astd_wakeflags)) + schedule(); + set_current_state(TASK_RUNNING); + + down(&astd_running); + if (test_and_clear_bit(WAKE_ASTS, &astd_wakeflags)) + process_asts(); + up(&astd_running); + } + return 0; +} + +void dlm_astd_wake(void) +{ + if (!no_asts()) { + set_bit(WAKE_ASTS, &astd_wakeflags); + wake_up_process(astd_task); + } +} + +int dlm_astd_start(void) +{ + struct task_struct *p; + int error = 0; + + INIT_LIST_HEAD(&ast_queue); + spin_lock_init(&ast_queue_lock); + init_MUTEX(&astd_running); + + p = kthread_run(dlm_astd, NULL, "dlm_astd"); + if (IS_ERR(p)) + error = PTR_ERR(p); + else + astd_task = p; + return error; +} + +void dlm_astd_stop(void) +{ + kthread_stop(astd_task); +} + +void dlm_astd_suspend(void) +{ + down(&astd_running); +} + +void dlm_astd_resume(void) +{ + up(&astd_running); +} + diff --git a/fs/dlm/ast.h b/fs/dlm/ast.h new file mode 100644 index 000000000000..6ee276c74c52 --- /dev/null +++ b/fs/dlm/ast.h @@ -0,0 +1,26 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __ASTD_DOT_H__ +#define __ASTD_DOT_H__ + +void dlm_add_ast(struct dlm_lkb *lkb, int type); +void dlm_del_ast(struct dlm_lkb *lkb); + +void dlm_astd_wake(void); +int dlm_astd_start(void); +void dlm_astd_stop(void); +void dlm_astd_suspend(void); +void dlm_astd_resume(void); + +#endif + diff --git a/fs/dlm/config.c b/fs/dlm/config.c new file mode 100644 index 000000000000..024ace9973a8 --- /dev/null +++ b/fs/dlm/config.c @@ -0,0 +1,787 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/configfs.h> +#include <net/sock.h> + +#include "config.h" + +/* + * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/nodeid + * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/weight + * /config/dlm/<cluster>/comms/<comm>/nodeid + * /config/dlm/<cluster>/comms/<comm>/local + * /config/dlm/<cluster>/comms/<comm>/addr + * The <cluster> level is useless, but I haven't figured out how to avoid it. + */ + +static struct config_group *space_list; +static struct config_group *comm_list; +static struct comm *local_comm; + +struct clusters; +struct cluster; +struct spaces; +struct space; +struct comms; +struct comm; +struct nodes; +struct node; + +static struct config_group *make_cluster(struct config_group *, const char *); +static void drop_cluster(struct config_group *, struct config_item *); +static void release_cluster(struct config_item *); +static struct config_group *make_space(struct config_group *, const char *); +static void drop_space(struct config_group *, struct config_item *); +static void release_space(struct config_item *); +static struct config_item *make_comm(struct config_group *, const char *); +static void drop_comm(struct config_group *, struct config_item *); +static void release_comm(struct config_item *); +static struct config_item *make_node(struct config_group *, const char *); +static void drop_node(struct config_group *, struct config_item *); +static void release_node(struct config_item *); + +static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a, + char *buf); +static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a, + const char *buf, size_t len); +static ssize_t show_node(struct config_item *i, struct configfs_attribute *a, + char *buf); +static ssize_t store_node(struct config_item *i, struct configfs_attribute *a, + const char *buf, size_t len); + +static ssize_t comm_nodeid_read(struct comm *cm, char *buf); +static ssize_t comm_nodeid_write(struct comm *cm, const char *buf, size_t len); +static ssize_t comm_local_read(struct comm *cm, char *buf); +static ssize_t comm_local_write(struct comm *cm, const char *buf, size_t len); +static ssize_t comm_addr_write(struct comm *cm, const char *buf, size_t len); +static ssize_t node_nodeid_read(struct node *nd, char *buf); +static ssize_t node_nodeid_write(struct node *nd, const char *buf, size_t len); +static ssize_t node_weight_read(struct node *nd, char *buf); +static ssize_t node_weight_write(struct node *nd, const char *buf, size_t len); + +enum { + COMM_ATTR_NODEID = 0, + COMM_ATTR_LOCAL, + COMM_ATTR_ADDR, +}; + +struct comm_attribute { + struct configfs_attribute attr; + ssize_t (*show)(struct comm *, char *); + ssize_t (*store)(struct comm *, const char *, size_t); +}; + +static struct comm_attribute comm_attr_nodeid = { + .attr = { .ca_owner = THIS_MODULE, + .ca_name = "nodeid", + .ca_mode = S_IRUGO | S_IWUSR }, + .show = comm_nodeid_read, + .store = comm_nodeid_write, +}; + +static struct comm_attribute comm_attr_local = { + .attr = { .ca_owner = THIS_MODULE, + .ca_name = "local", + .ca_mode = S_IRUGO | S_IWUSR }, + .show = comm_local_read, + .store = comm_local_write, +}; + +static struct comm_attribute comm_attr_addr = { + .attr = { .ca_owner = THIS_MODULE, + .ca_name = "addr", + .ca_mode = S_IRUGO | S_IWUSR }, + .store = comm_addr_write, +}; + +static struct configfs_attribute *comm_attrs[] = { + [COMM_ATTR_NODEID] = &comm_attr_nodeid.attr, + [COMM_ATTR_LOCAL] = &comm_attr_local.attr, + [COMM_ATTR_ADDR] = &comm_attr_addr.attr, + NULL, +}; + +enum { + NODE_ATTR_NODEID = 0, + NODE_ATTR_WEIGHT, +}; + +struct node_attribute { + struct configfs_attribute attr; + ssize_t (*show)(struct node *, char *); + ssize_t (*store)(struct node *, const char *, size_t); +}; + +static struct node_attribute node_attr_nodeid = { + .attr = { .ca_owner = THIS_MODULE, + .ca_name = "nodeid", + .ca_mode = S_IRUGO | S_IWUSR }, + .show = node_nodeid_read, + .store = node_nodeid_write, +}; + +static struct node_attribute node_attr_weight = { + .attr = { .ca_owner = THIS_MODULE, + .ca_name = "weight", + .ca_mode = S_IRUGO | S_IWUSR }, + .show = node_weight_read, + .store = node_weight_write, +}; + +static struct configfs_attribute *node_attrs[] = { + [NODE_ATTR_NODEID] = &node_attr_nodeid.attr, + [NODE_ATTR_WEIGHT] = &node_attr_weight.attr, + NULL, +}; + +struct clusters { + struct configfs_subsystem subsys; +}; + +struct cluster { + struct config_group group; +}; + +struct spaces { + struct config_group ss_group; +}; + +struct space { + struct config_group group; + struct list_head members; + struct semaphore members_lock; + int members_count; +}; + +struct comms { + struct config_group cs_group; +}; + +struct comm { + struct config_item item; + int nodeid; + int local; + int addr_count; + struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT]; +}; + +struct nodes { + struct config_group ns_group; +}; + +struct node { + struct config_item item; + struct list_head list; /* space->members */ + int nodeid; + int weight; +}; + +static struct configfs_group_operations clusters_ops = { + .make_group = make_cluster, + .drop_item = drop_cluster, +}; + +static struct configfs_item_operations cluster_ops = { + .release = release_cluster, +}; + +static struct configfs_group_operations spaces_ops = { + .make_group = make_space, + .drop_item = drop_space, +}; + +static struct configfs_item_operations space_ops = { + .release = release_space, +}; + +static struct configfs_group_operations comms_ops = { + .make_item = make_comm, + .drop_item = drop_comm, +}; + +static struct configfs_item_operations comm_ops = { + .release = release_comm, + .show_attribute = show_comm, + .store_attribute = store_comm, +}; + +static struct configfs_group_operations nodes_ops = { + .make_item = make_node, + .drop_item = drop_node, +}; + +static struct configfs_item_operations node_ops = { + .release = release_node, + .show_attribute = show_node, + .store_attribute = store_node, +}; + +static struct config_item_type clusters_type = { + .ct_group_ops = &clusters_ops, + .ct_owner = THIS_MODULE, +}; + +static struct config_item_type cluster_type = { + .ct_item_ops = &cluster_ops, + .ct_owner = THIS_MODULE, +}; + +static struct config_item_type spaces_type = { + .ct_group_ops = &spaces_ops, + .ct_owner = THIS_MODULE, +}; + +static struct config_item_type space_type = { + .ct_item_ops = &space_ops, + .ct_owner = THIS_MODULE, +}; + +static struct config_item_type comms_type = { + .ct_group_ops = &comms_ops, + .ct_owner = THIS_MODULE, +}; + +static struct config_item_type comm_type = { + .ct_item_ops = &comm_ops, + .ct_attrs = comm_attrs, + .ct_owner = THIS_MODULE, +}; + +static struct config_item_type nodes_type = { + .ct_group_ops = &nodes_ops, + .ct_owner = THIS_MODULE, +}; + +static struct config_item_type node_type = { + .ct_item_ops = &node_ops, + .ct_attrs = node_attrs, + .ct_owner = THIS_MODULE, +}; + +static struct cluster *to_cluster(struct config_item *i) +{ + return i ? container_of(to_config_group(i), struct cluster, group):NULL; +} + +static struct space *to_space(struct config_item *i) +{ + return i ? container_of(to_config_group(i), struct space, group) : NULL; +} + +static struct comm *to_comm(struct config_item *i) +{ + return i ? container_of(i, struct comm, item) : NULL; +} + +static struct node *to_node(struct config_item *i) +{ + return i ? container_of(i, struct node, item) : NULL; +} + +static struct config_group *make_cluster(struct config_group *g, + const char *name) +{ + struct cluster *cl = NULL; + struct spaces *sps = NULL; + struct comms *cms = NULL; + void *gps = NULL; + + cl = kzalloc(sizeof(struct cluster), GFP_KERNEL); + gps = kcalloc(3, sizeof(struct config_group *), GFP_KERNEL); + sps = kzalloc(sizeof(struct spaces), GFP_KERNEL); + cms = kzalloc(sizeof(struct comms), GFP_KERNEL); + + if (!cl || !gps || !sps || !cms) + goto fail; + + config_group_init_type_name(&cl->group, name, &cluster_type); + config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type); + config_group_init_type_name(&cms->cs_group, "comms", &comms_type); + + cl->group.default_groups = gps; + cl->group.default_groups[0] = &sps->ss_group; + cl->group.default_groups[1] = &cms->cs_group; + cl->group.default_groups[2] = NULL; + + space_list = &sps->ss_group; + comm_list = &cms->cs_group; + return &cl->group; + + fail: + kfree(cl); + kfree(gps); + kfree(sps); + kfree(cms); + return NULL; +} + +static void drop_cluster(struct config_group *g, struct config_item *i) +{ + struct cluster *cl = to_cluster(i); + struct config_item *tmp; + int j; + + for (j = 0; cl->group.default_groups[j]; j++) { + tmp = &cl->group.default_groups[j]->cg_item; + cl->group.default_groups[j] = NULL; + config_item_put(tmp); + } + + space_list = NULL; + comm_list = NULL; + + config_item_put(i); +} + +static void release_cluster(struct config_item *i) +{ + struct cluster *cl = to_cluster(i); + kfree(cl->group.default_groups); + kfree(cl); +} + +static struct config_group *make_space(struct config_group *g, const char *name) +{ + struct space *sp = NULL; + struct nodes *nds = NULL; + void *gps = NULL; + + sp = kzalloc(sizeof(struct space), GFP_KERNEL); + gps = kcalloc(2, sizeof(struct config_group *), GFP_KERNEL); + nds = kzalloc(sizeof(struct nodes), GFP_KERNEL); + + if (!sp || !gps || !nds) + goto fail; + + config_group_init_type_name(&sp->group, name, &space_type); + config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type); + + sp->group.default_groups = gps; + sp->group.default_groups[0] = &nds->ns_group; + sp->group.default_groups[1] = NULL; + + INIT_LIST_HEAD(&sp->members); + init_MUTEX(&sp->members_lock); + sp->members_count = 0; + return &sp->group; + + fail: + kfree(sp); + kfree(gps); + kfree(nds); + return NULL; +} + +static void drop_space(struct config_group *g, struct config_item *i) +{ + struct space *sp = to_space(i); + struct config_item *tmp; + int j; + + /* assert list_empty(&sp->members) */ + + for (j = 0; sp->group.default_groups[j]; j++) { + tmp = &sp->group.default_groups[j]->cg_item; + sp->group.default_groups[j] = NULL; + config_item_put(tmp); + } + + config_item_put(i); +} + +static void release_space(struct config_item *i) +{ + struct space *sp = to_space(i); + kfree(sp->group.default_groups); + kfree(sp); +} + +static struct config_item *make_comm(struct config_group *g, const char *name) +{ + struct comm *cm; + + cm = kzalloc(sizeof(struct comm), GFP_KERNEL); + if (!cm) + return NULL; + + config_item_init_type_name(&cm->item, name, &comm_type); + cm->nodeid = -1; + cm->local = 0; + cm->addr_count = 0; + return &cm->item; +} + +static void drop_comm(struct config_group *g, struct config_item *i) +{ + struct comm *cm = to_comm(i); + if (local_comm == cm) + local_comm = NULL; + while (cm->addr_count--) + kfree(cm->addr[cm->addr_count]); + config_item_put(i); +} + +static void release_comm(struct config_item *i) +{ + struct comm *cm = to_comm(i); + kfree(cm); +} + +static struct config_item *make_node(struct config_group *g, const char *name) +{ + struct space *sp = to_space(g->cg_item.ci_parent); + struct node *nd; + + nd = kzalloc(sizeof(struct node), GFP_KERNEL); + if (!nd) + return NULL; + + config_item_init_type_name(&nd->item, name, &node_type); + nd->nodeid = -1; + nd->weight = 1; /* default weight of 1 if none is set */ + + down(&sp->members_lock); + list_add(&nd->list, &sp->members); + sp->members_count++; + up(&sp->members_lock); + + return &nd->item; +} + +static void drop_node(struct config_group *g, struct config_item *i) +{ + struct space *sp = to_space(g->cg_item.ci_parent); + struct node *nd = to_node(i); + + down(&sp->members_lock); + list_del(&nd->list); + sp->members_count--; + up(&sp->members_lock); + + config_item_put(i); +} + +static void release_node(struct config_item *i) +{ + struct node *nd = to_node(i); + kfree(nd); +} + +static struct clusters clusters_root = { + .subsys = { + .su_group = { + .cg_item = { + .ci_namebuf = "dlm", + .ci_type = &clusters_type, + }, + }, + }, +}; + +int dlm_config_init(void) +{ + config_group_init(&clusters_root.subsys.su_group); + init_MUTEX(&clusters_root.subsys.su_sem); + return configfs_register_subsystem(&clusters_root.subsys); +} + +void dlm_config_exit(void) +{ + configfs_unregister_subsystem(&clusters_root.subsys); +} + +/* + * Functions for user space to read/write attributes + */ + +static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a, + char *buf) +{ + struct comm *cm = to_comm(i); + struct comm_attribute *cma = + container_of(a, struct comm_attribute, attr); + return cma->show ? cma->show(cm, buf) : 0; +} + +static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a, + const char *buf, size_t len) +{ + struct comm *cm = to_comm(i); + struct comm_attribute *cma = + container_of(a, struct comm_attribute, attr); + return cma->store ? cma->store(cm, buf, len) : -EINVAL; +} + +static ssize_t comm_nodeid_read(struct comm *cm, char *buf) +{ + return sprintf(buf, "%d\n", cm->nodeid); +} + +static ssize_t comm_nodeid_write(struct comm *cm, const char *buf, size_t len) +{ + cm->nodeid = simple_strtol(buf, NULL, 0); + return len; +} + +static ssize_t comm_local_read(struct comm *cm, char *buf) +{ + return sprintf(buf, "%d\n", cm->local); +} + +static ssize_t comm_local_write(struct comm *cm, const char *buf, size_t len) +{ + cm->local= simple_strtol(buf, NULL, 0); + if (cm->local && !local_comm) + local_comm = cm; + return len; +} + +static ssize_t comm_addr_write(struct comm *cm, const char *buf, size_t len) +{ + struct sockaddr_storage *addr; + + if (len != sizeof(struct sockaddr_storage)) + return -EINVAL; + + if (cm->addr_count >= DLM_MAX_ADDR_COUNT) + return -ENOSPC; + + addr = kzalloc(sizeof(*addr), GFP_KERNEL); + if (!addr) + return -ENOMEM; + + memcpy(addr, buf, len); + cm->addr[cm->addr_count++] = addr; + return len; +} + +static ssize_t show_node(struct config_item *i, struct configfs_attribute *a, + char *buf) +{ + struct node *nd = to_node(i); + struct node_attribute *nda = + container_of(a, struct node_attribute, attr); + return nda->show ? nda->show(nd, buf) : 0; +} + +static ssize_t store_node(struct config_item *i, struct configfs_attribute *a, + const char *buf, size_t len) +{ + struct node *nd = to_node(i); + struct node_attribute *nda = + container_of(a, struct node_attribute, attr); + return nda->store ? nda->store(nd, buf, len) : -EINVAL; +} + +static ssize_t node_nodeid_read(struct node *nd, char *buf) +{ + return sprintf(buf, "%d\n", nd->nodeid); +} + +static ssize_t node_nodeid_write(struct node *nd, const char *buf, size_t len) +{ + nd->nodeid = simple_strtol(buf, NULL, 0); + return len; +} + +static ssize_t node_weight_read(struct node *nd, char *buf) +{ + return sprintf(buf, "%d\n", nd->weight); +} + +static ssize_t node_weight_write(struct node *nd, const char *buf, size_t len) +{ + nd->weight = simple_strtol(buf, NULL, 0); + return len; +} + +/* + * Functions for the dlm to get the info that's been configured + */ + +static struct space *get_space(char *name) +{ + if (!space_list) + return NULL; + return to_space(config_group_find_obj(space_list, name)); +} + +static void put_space(struct space *sp) +{ + config_item_put(&sp->group.cg_item); +} + +static struct comm *get_comm(int nodeid, struct sockaddr_storage *addr) +{ + struct config_item *i; + struct comm *cm = NULL; + int found = 0; + + if (!comm_list) + return NULL; + + down(&clusters_root.subsys.su_sem); + + list_for_each_entry(i, &comm_list->cg_children, ci_entry) { + cm = to_comm(i); + + if (nodeid) { + if (cm->nodeid != nodeid) + continue; + found = 1; + break; + } else { + if (!cm->addr_count || + memcmp(cm->addr[0], addr, sizeof(*addr))) + continue; + found = 1; + break; + } + } + up(&clusters_root.subsys.su_sem); + + if (found) + config_item_get(i); + else + cm = NULL; + return cm; +} + +static void put_comm(struct comm *cm) +{ + config_item_put(&cm->item); +} + +/* caller must free mem */ +int dlm_nodeid_list(char *lsname, int **ids_out) +{ + struct space *sp; + struct node *nd; + int i = 0, rv = 0; + int *ids; + + sp = get_space(lsname); + if (!sp) + return -EEXIST; + + down(&sp->members_lock); + if (!sp->members_count) { + rv = 0; + goto out; + } + + ids = kcalloc(sp->members_count, sizeof(int), GFP_KERNEL); + if (!ids) { + rv = -ENOMEM; + goto out; + } + + rv = sp->members_count; + list_for_each_entry(nd, &sp->members, list) + ids[i++] = nd->nodeid; + + if (rv != i) + printk("bad nodeid count %d %d\n", rv, i); + + *ids_out = ids; + out: + up(&sp->members_lock); + put_space(sp); + return rv; +} + +int dlm_node_weight(char *lsname, int nodeid) +{ + struct space *sp; + struct node *nd; + int w = -EEXIST; + + sp = get_space(lsname); + if (!sp) + goto out; + + down(&sp->members_lock); + list_for_each_entry(nd, &sp->members, list) { + if (nd->nodeid != nodeid) + continue; + w = nd->weight; + break; + } + up(&sp->members_lock); + put_space(sp); + out: + return w; +} + +int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr) +{ + struct comm *cm = get_comm(nodeid, NULL); + if (!cm) + return -EEXIST; + if (!cm->addr_count) + return -ENOENT; + memcpy(addr, cm->addr[0], sizeof(*addr)); + put_comm(cm); + return 0; +} + +int dlm_addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid) +{ + struct comm *cm = get_comm(0, addr); + if (!cm) + return -EEXIST; + *nodeid = cm->nodeid; + put_comm(cm); + return 0; +} + +int dlm_our_nodeid(void) +{ + return local_comm ? local_comm->nodeid : 0; +} + +/* num 0 is first addr, num 1 is second addr */ +int dlm_our_addr(struct sockaddr_storage *addr, int num) +{ + if (!local_comm) + return -1; + if (num + 1 > local_comm->addr_count) + return -1; + memcpy(addr, local_comm->addr[num], sizeof(*addr)); + return 0; +} + +/* Config file defaults */ +#define DEFAULT_TCP_PORT 21064 +#define DEFAULT_BUFFER_SIZE 4096 +#define DEFAULT_RSBTBL_SIZE 256 +#define DEFAULT_LKBTBL_SIZE 1024 +#define DEFAULT_DIRTBL_SIZE 512 +#define DEFAULT_RECOVER_TIMER 5 +#define DEFAULT_TOSS_SECS 10 +#define DEFAULT_SCAN_SECS 5 + +struct dlm_config_info dlm_config = { + .tcp_port = DEFAULT_TCP_PORT, + .buffer_size = DEFAULT_BUFFER_SIZE, + .rsbtbl_size = DEFAULT_RSBTBL_SIZE, + .lkbtbl_size = DEFAULT_LKBTBL_SIZE, + .dirtbl_size = DEFAULT_DIRTBL_SIZE, + .recover_timer = DEFAULT_RECOVER_TIMER, + .toss_secs = DEFAULT_TOSS_SECS, + .scan_secs = DEFAULT_SCAN_SECS +}; + diff --git a/fs/dlm/config.h b/fs/dlm/config.h new file mode 100644 index 000000000000..9da7839958a9 --- /dev/null +++ b/fs/dlm/config.h @@ -0,0 +1,42 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __CONFIG_DOT_H__ +#define __CONFIG_DOT_H__ + +#define DLM_MAX_ADDR_COUNT 3 + +struct dlm_config_info { + int tcp_port; + int buffer_size; + int rsbtbl_size; + int lkbtbl_size; + int dirtbl_size; + int recover_timer; + int toss_secs; + int scan_secs; +}; + +extern struct dlm_config_info dlm_config; + +int dlm_config_init(void); +void dlm_config_exit(void); +int dlm_node_weight(char *lsname, int nodeid); +int dlm_nodeid_list(char *lsname, int **ids_out); +int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr); +int dlm_addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid); +int dlm_our_nodeid(void); +int dlm_our_addr(struct sockaddr_storage *addr, int num); + +#endif /* __CONFIG_DOT_H__ */ + diff --git a/fs/dlm/debug_fs.c b/fs/dlm/debug_fs.c new file mode 100644 index 000000000000..98b49a1ece47 --- /dev/null +++ b/fs/dlm/debug_fs.c @@ -0,0 +1,310 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include <linux/pagemap.h> +#include <linux/seq_file.h> +#include <linux/module.h> +#include <linux/ctype.h> +#include <linux/debugfs.h> + +#include "dlm_internal.h" + + +static struct dentry *dlm_root; + +struct rsb_iter { + int entry; + struct dlm_ls *ls; + struct list_head *next; + struct dlm_rsb *rsb; +}; + +static char *print_lockmode(int mode) +{ + switch (mode) { + case DLM_LOCK_IV: + return "--"; + case DLM_LOCK_NL: + return "NL"; + case DLM_LOCK_CR: + return "CR"; + case DLM_LOCK_CW: + return "CW"; + case DLM_LOCK_PR: + return "PR"; + case DLM_LOCK_PW: + return "PW"; + case DLM_LOCK_EX: + return "EX"; + default: + return "??"; + } +} + +static void print_lock(struct seq_file *s, struct dlm_lkb *lkb, + struct dlm_rsb *res) +{ + seq_printf(s, "%08x %s", lkb->lkb_id, print_lockmode(lkb->lkb_grmode)); + + if (lkb->lkb_status == DLM_LKSTS_CONVERT + || lkb->lkb_status == DLM_LKSTS_WAITING) + seq_printf(s, " (%s)", print_lockmode(lkb->lkb_rqmode)); + + if (lkb->lkb_range) { + /* FIXME: this warns on Alpha */ + if (lkb->lkb_status == DLM_LKSTS_CONVERT + || lkb->lkb_status == DLM_LKSTS_GRANTED) + seq_printf(s, " %" PRIx64 "-%" PRIx64, + lkb->lkb_range[GR_RANGE_START], + lkb->lkb_range[GR_RANGE_END]); + if (lkb->lkb_status == DLM_LKSTS_CONVERT + || lkb->lkb_status == DLM_LKSTS_WAITING) + seq_printf(s, " (%" PRIx64 "-%" PRIx64 ")", + lkb->lkb_range[RQ_RANGE_START], + lkb->lkb_range[RQ_RANGE_END]); + } + + if (lkb->lkb_nodeid) { + if (lkb->lkb_nodeid != res->res_nodeid) + seq_printf(s, " Remote: %3d %08x", lkb->lkb_nodeid, + lkb->lkb_remid); + else + seq_printf(s, " Master: %08x", lkb->lkb_remid); + } + + if (lkb->lkb_wait_type) + seq_printf(s, " wait_type: %d", lkb->lkb_wait_type); + + seq_printf(s, "\n"); +} + +static int print_resource(struct dlm_rsb *res, struct seq_file *s) +{ + struct dlm_lkb *lkb; + int i, lvblen = res->res_ls->ls_lvblen; + + seq_printf(s, "\nResource %p Name (len=%d) \"", res, res->res_length); + for (i = 0; i < res->res_length; i++) { + if (isprint(res->res_name[i])) + seq_printf(s, "%c", res->res_name[i]); + else + seq_printf(s, "%c", '.'); + } + if (res->res_nodeid > 0) + seq_printf(s, "\" \nLocal Copy, Master is node %d\n", + res->res_nodeid); + else if (res->res_nodeid == 0) + seq_printf(s, "\" \nMaster Copy\n"); + else if (res->res_nodeid == -1) + seq_printf(s, "\" \nLooking up master (lkid %x)\n", + res->res_first_lkid); + else + seq_printf(s, "\" \nInvalid master %d\n", res->res_nodeid); + + /* Print the LVB: */ + if (res->res_lvbptr) { + seq_printf(s, "LVB: "); + for (i = 0; i < lvblen; i++) { + if (i == lvblen / 2) + seq_printf(s, "\n "); + seq_printf(s, "%02x ", + (unsigned char) res->res_lvbptr[i]); + } + if (rsb_flag(res, RSB_VALNOTVALID)) + seq_printf(s, " (INVALID)"); + seq_printf(s, "\n"); + } + + /* Print the locks attached to this resource */ + seq_printf(s, "Granted Queue\n"); + list_for_each_entry(lkb, &res->res_grantqueue, lkb_statequeue) + print_lock(s, lkb, res); + + seq_printf(s, "Conversion Queue\n"); + list_for_each_entry(lkb, &res->res_convertqueue, lkb_statequeue) + print_lock(s, lkb, res); + + seq_printf(s, "Waiting Queue\n"); + list_for_each_entry(lkb, &res->res_waitqueue, lkb_statequeue) + print_lock(s, lkb, res); + + return 0; +} + +static int rsb_iter_next(struct rsb_iter *ri) +{ + struct dlm_ls *ls = ri->ls; + int i; + + if (!ri->next) { + top: + /* Find the next non-empty hash bucket */ + for (i = ri->entry; i < ls->ls_rsbtbl_size; i++) { + read_lock(&ls->ls_rsbtbl[i].lock); + if (!list_empty(&ls->ls_rsbtbl[i].list)) { + ri->next = ls->ls_rsbtbl[i].list.next; + read_unlock(&ls->ls_rsbtbl[i].lock); + break; + } + read_unlock(&ls->ls_rsbtbl[i].lock); + } + ri->entry = i; + + if (ri->entry >= ls->ls_rsbtbl_size) + return 1; + } else { + i = ri->entry; + read_lock(&ls->ls_rsbtbl[i].lock); + ri->next = ri->next->next; + if (ri->next->next == ls->ls_rsbtbl[i].list.next) { + /* End of list - move to next bucket */ + ri->next = NULL; + ri->entry++; + read_unlock(&ls->ls_rsbtbl[i].lock); + goto top; + } + read_unlock(&ls->ls_rsbtbl[i].lock); + } + ri->rsb = list_entry(ri->next, struct dlm_rsb, res_hashchain); + + return 0; +} + +static void rsb_iter_free(struct rsb_iter *ri) +{ + kfree(ri); +} + +static struct rsb_iter *rsb_iter_init(struct dlm_ls *ls) +{ + struct rsb_iter *ri; + + ri = kmalloc(sizeof *ri, GFP_KERNEL); + if (!ri) + return NULL; + + ri->ls = ls; + ri->entry = 0; + ri->next = NULL; + + if (rsb_iter_next(ri)) { + rsb_iter_free(ri); + return NULL; + } + + return ri; +} + +static void *seq_start(struct seq_file *file, loff_t *pos) +{ + struct rsb_iter *ri; + loff_t n = *pos; + + ri = rsb_iter_init(file->private); + if (!ri) + return NULL; + + while (n--) { + if (rsb_iter_next(ri)) { + rsb_iter_free(ri); + return NULL; + } + } + + return ri; +} + +static void *seq_next(struct seq_file *file, void *iter_ptr, loff_t *pos) +{ + struct rsb_iter *ri = iter_ptr; + + (*pos)++; + + if (rsb_iter_next(ri)) { + rsb_iter_free(ri); + return NULL; + } + + return ri; +} + +static void seq_stop(struct seq_file *file, void *iter_ptr) +{ + /* nothing for now */ +} + +static int seq_show(struct seq_file *file, void *iter_ptr) +{ + struct rsb_iter *ri = iter_ptr; + + print_resource(ri->rsb, file); + + return 0; +} + +static struct seq_operations dlm_seq_ops = { + .start = seq_start, + .next = seq_next, + .stop = seq_stop, + .show = seq_show, +}; + +static int do_open(struct inode *inode, struct file *file) +{ + struct seq_file *seq; + int ret; + + ret = seq_open(file, &dlm_seq_ops); + if (ret) + return ret; + + seq = file->private_data; + seq->private = inode->u.generic_ip; + + return 0; +} + +static struct file_operations dlm_fops = { + .owner = THIS_MODULE, + .open = do_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release +}; + +int dlm_create_debug_file(struct dlm_ls *ls) +{ + ls->ls_debug_dentry = debugfs_create_file(ls->ls_name, + S_IFREG | S_IRUGO, + dlm_root, + ls, + &dlm_fops); + return ls->ls_debug_dentry ? 0 : -ENOMEM; +} + +void dlm_delete_debug_file(struct dlm_ls *ls) +{ + if (ls->ls_debug_dentry) + debugfs_remove(ls->ls_debug_dentry); +} + +int dlm_register_debugfs(void) +{ + dlm_root = debugfs_create_dir("dlm", NULL); + return dlm_root ? 0 : -ENOMEM; +} + +void dlm_unregister_debugfs(void) +{ + debugfs_remove(dlm_root); +} + diff --git a/fs/dlm/device.c b/fs/dlm/device.c new file mode 100644 index 000000000000..a8bf600ed13d --- /dev/null +++ b/fs/dlm/device.c @@ -0,0 +1,1084 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +/* + * device.c + * + * This is the userland interface to the DLM. + * + * The locking is done via a misc char device (find the + * registered minor number in /proc/misc). + * + * User code should not use this interface directly but + * call the library routines in libdlm.a instead. + * + */ + +#include <linux/miscdevice.h> +#include <linux/init.h> +#include <linux/wait.h> +#include <linux/module.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/poll.h> +#include <linux/signal.h> +#include <linux/spinlock.h> +#include <linux/idr.h> + +#include <linux/dlm.h> +#include <linux/dlm_device.h> + +#include "lvb_table.h" + +static struct file_operations _dlm_fops; +static const char *name_prefix="dlm"; +static struct list_head user_ls_list; +static struct semaphore user_ls_lock; + +/* Lock infos are stored in here indexed by lock ID */ +static DEFINE_IDR(lockinfo_idr); +static rwlock_t lockinfo_lock; + +/* Flags in li_flags */ +#define LI_FLAG_COMPLETE 1 +#define LI_FLAG_FIRSTLOCK 2 +#define LI_FLAG_PERSISTENT 3 + +/* flags in ls_flags*/ +#define LS_FLAG_DELETED 1 +#define LS_FLAG_AUTOFREE 2 + + +#define LOCKINFO_MAGIC 0x53595324 + +struct lock_info { + uint32_t li_magic; + uint8_t li_cmd; + int8_t li_grmode; + int8_t li_rqmode; + struct dlm_lksb li_lksb; + wait_queue_head_t li_waitq; + unsigned long li_flags; + void __user *li_castparam; + void __user *li_castaddr; + void __user *li_bastparam; + void __user *li_bastaddr; + void __user *li_pend_bastparam; + void __user *li_pend_bastaddr; + struct list_head li_ownerqueue; + struct file_info *li_file; + struct dlm_lksb __user *li_user_lksb; + struct semaphore li_firstlock; +}; + +/* A queued AST no less */ +struct ast_info { + struct dlm_lock_result result; + struct list_head list; + uint32_t lvb_updated; + uint32_t progress; /* How much has been read */ +}; + +/* One of these per userland lockspace */ +struct user_ls { + void *ls_lockspace; + atomic_t ls_refcnt; + long ls_flags; + + /* Passed into misc_register() */ + struct miscdevice ls_miscinfo; + struct list_head ls_list; +}; + +/* misc_device info for the control device */ +static struct miscdevice ctl_device; + +/* + * Stuff we hang off the file struct. + * The first two are to cope with unlocking all the + * locks help by a process when it dies. + */ +struct file_info { + struct list_head fi_li_list; /* List of active lock_infos */ + spinlock_t fi_li_lock; + struct list_head fi_ast_list; /* Queue of ASTs to be delivered */ + spinlock_t fi_ast_lock; + wait_queue_head_t fi_wait; + struct user_ls *fi_ls; + atomic_t fi_refcnt; /* Number of users */ + unsigned long fi_flags; /* Bit 1 means the device is open */ +}; + + +/* get and put ops for file_info. + Actually I don't really like "get" and "put", but everyone + else seems to use them and I can't think of anything + nicer at the moment */ +static void get_file_info(struct file_info *f) +{ + atomic_inc(&f->fi_refcnt); +} + +static void put_file_info(struct file_info *f) +{ + if (atomic_dec_and_test(&f->fi_refcnt)) + kfree(f); +} + +static void release_lockinfo(struct lock_info *li) +{ + put_file_info(li->li_file); + + write_lock(&lockinfo_lock); + idr_remove(&lockinfo_idr, li->li_lksb.sb_lkid); + write_unlock(&lockinfo_lock); + + if (li->li_lksb.sb_lvbptr) + kfree(li->li_lksb.sb_lvbptr); + kfree(li); + + module_put(THIS_MODULE); +} + +static struct lock_info *get_lockinfo(uint32_t lockid) +{ + struct lock_info *li; + + read_lock(&lockinfo_lock); + li = idr_find(&lockinfo_idr, lockid); + read_unlock(&lockinfo_lock); + + return li; +} + +static int add_lockinfo(struct lock_info *li) +{ + int n; + int r; + int ret = -EINVAL; + + write_lock(&lockinfo_lock); + + if (idr_find(&lockinfo_idr, li->li_lksb.sb_lkid)) + goto out_up; + + ret = -ENOMEM; + r = idr_pre_get(&lockinfo_idr, GFP_KERNEL); + if (!r) + goto out_up; + + r = idr_get_new_above(&lockinfo_idr, li, li->li_lksb.sb_lkid, &n); + if (r) + goto out_up; + + if (n != li->li_lksb.sb_lkid) { + idr_remove(&lockinfo_idr, n); + goto out_up; + } + + ret = 0; + + out_up: + write_unlock(&lockinfo_lock); + + return ret; +} + + +static struct user_ls *__find_lockspace(int minor) +{ + struct user_ls *lsinfo; + + list_for_each_entry(lsinfo, &user_ls_list, ls_list) { + if (lsinfo->ls_miscinfo.minor == minor) + return lsinfo; + } + return NULL; +} + +/* Find a lockspace struct given the device minor number */ +static struct user_ls *find_lockspace(int minor) +{ + struct user_ls *lsinfo; + + down(&user_ls_lock); + lsinfo = __find_lockspace(minor); + up(&user_ls_lock); + + return lsinfo; +} + +static void add_lockspace_to_list(struct user_ls *lsinfo) +{ + down(&user_ls_lock); + list_add(&lsinfo->ls_list, &user_ls_list); + up(&user_ls_lock); +} + +/* Register a lockspace with the DLM and create a misc + device for userland to access it */ +static int register_lockspace(char *name, struct user_ls **ls, int flags) +{ + struct user_ls *newls; + int status; + int namelen; + + namelen = strlen(name)+strlen(name_prefix)+2; + + newls = kmalloc(sizeof(struct user_ls), GFP_KERNEL); + if (!newls) + return -ENOMEM; + memset(newls, 0, sizeof(struct user_ls)); + + newls->ls_miscinfo.name = kmalloc(namelen, GFP_KERNEL); + if (!newls->ls_miscinfo.name) { + kfree(newls); + return -ENOMEM; + } + + status = dlm_new_lockspace(name, strlen(name), &newls->ls_lockspace, 0, + DLM_USER_LVB_LEN); + if (status != 0) { + kfree(newls->ls_miscinfo.name); + kfree(newls); + return status; + } + + snprintf((char*)newls->ls_miscinfo.name, namelen, "%s_%s", + name_prefix, name); + + newls->ls_miscinfo.fops = &_dlm_fops; + newls->ls_miscinfo.minor = MISC_DYNAMIC_MINOR; + + status = misc_register(&newls->ls_miscinfo); + if (status) { + printk(KERN_ERR "dlm: misc register failed for %s\n", name); + dlm_release_lockspace(newls->ls_lockspace, 0); + kfree(newls->ls_miscinfo.name); + kfree(newls); + return status; + } + + if (flags & DLM_USER_LSFLG_AUTOFREE) + set_bit(LS_FLAG_AUTOFREE, &newls->ls_flags); + + add_lockspace_to_list(newls); + *ls = newls; + return 0; +} + +/* Called with the user_ls_lock semaphore held */ +static int unregister_lockspace(struct user_ls *lsinfo, int force) +{ + int status; + + status = dlm_release_lockspace(lsinfo->ls_lockspace, force); + if (status) + return status; + + status = misc_deregister(&lsinfo->ls_miscinfo); + if (status) + return status; + + list_del(&lsinfo->ls_list); + set_bit(LS_FLAG_DELETED, &lsinfo->ls_flags); + lsinfo->ls_lockspace = NULL; + if (atomic_read(&lsinfo->ls_refcnt) == 0) { + kfree(lsinfo->ls_miscinfo.name); + kfree(lsinfo); + } + + return 0; +} + +/* Add it to userland's AST queue */ +static void add_to_astqueue(struct lock_info *li, void *astaddr, void *astparam, + int lvb_updated) +{ + struct ast_info *ast = kmalloc(sizeof(struct ast_info), GFP_KERNEL); + if (!ast) + return; + + memset(ast, 0, sizeof(*ast)); + ast->result.user_astparam = astparam; + ast->result.user_astaddr = astaddr; + ast->result.user_lksb = li->li_user_lksb; + memcpy(&ast->result.lksb, &li->li_lksb, sizeof(struct dlm_lksb)); + ast->lvb_updated = lvb_updated; + + spin_lock(&li->li_file->fi_ast_lock); + list_add_tail(&ast->list, &li->li_file->fi_ast_list); + spin_unlock(&li->li_file->fi_ast_lock); + wake_up_interruptible(&li->li_file->fi_wait); +} + +static void bast_routine(void *param, int mode) +{ + struct lock_info *li = param; + + if (li && li->li_bastaddr) + add_to_astqueue(li, li->li_bastaddr, li->li_bastparam, 0); +} + +/* + * This is the kernel's AST routine. + * All lock, unlock & query operations complete here. + * The only syncronous ops are those done during device close. + */ +static void ast_routine(void *param) +{ + struct lock_info *li = param; + + /* Param may be NULL if a persistent lock is unlocked by someone else */ + if (!li) + return; + + /* If this is a succesful conversion then activate the blocking ast + * args from the conversion request */ + if (!test_bit(LI_FLAG_FIRSTLOCK, &li->li_flags) && + li->li_lksb.sb_status == 0) { + + li->li_bastparam = li->li_pend_bastparam; + li->li_bastaddr = li->li_pend_bastaddr; + li->li_pend_bastaddr = NULL; + } + + /* If it's an async request then post data to the user's AST queue. */ + if (li->li_castaddr) { + int lvb_updated = 0; + + /* See if the lvb has been updated */ + if (dlm_lvb_operations[li->li_grmode+1][li->li_rqmode+1] == 1) + lvb_updated = 1; + + if (li->li_lksb.sb_status == 0) + li->li_grmode = li->li_rqmode; + + /* Only queue AST if the device is still open */ + if (test_bit(1, &li->li_file->fi_flags)) + add_to_astqueue(li, li->li_castaddr, li->li_castparam, + lvb_updated); + + /* If it's a new lock operation that failed, then + * remove it from the owner queue and free the + * lock_info. + */ + if (test_and_clear_bit(LI_FLAG_FIRSTLOCK, &li->li_flags) && + li->li_lksb.sb_status != 0) { + + /* Wait till dlm_lock() has finished */ + down(&li->li_firstlock); + up(&li->li_firstlock); + + spin_lock(&li->li_file->fi_li_lock); + list_del(&li->li_ownerqueue); + spin_unlock(&li->li_file->fi_li_lock); + release_lockinfo(li); + return; + } + /* Free unlocks & queries */ + if (li->li_lksb.sb_status == -DLM_EUNLOCK || + li->li_cmd == DLM_USER_QUERY) { + release_lockinfo(li); + } + } else { + /* Synchronous request, just wake up the caller */ + set_bit(LI_FLAG_COMPLETE, &li->li_flags); + wake_up_interruptible(&li->li_waitq); + } +} + +/* + * Wait for the lock op to complete and return the status. + */ +static int wait_for_ast(struct lock_info *li) +{ + /* Wait for the AST routine to complete */ + set_task_state(current, TASK_INTERRUPTIBLE); + while (!test_bit(LI_FLAG_COMPLETE, &li->li_flags)) + schedule(); + + set_task_state(current, TASK_RUNNING); + + return li->li_lksb.sb_status; +} + + +/* Open on control device */ +static int dlm_ctl_open(struct inode *inode, struct file *file) +{ + file->private_data = NULL; + return 0; +} + +/* Close on control device */ +static int dlm_ctl_close(struct inode *inode, struct file *file) +{ + return 0; +} + +/* Open on lockspace device */ +static int dlm_open(struct inode *inode, struct file *file) +{ + struct file_info *f; + struct user_ls *lsinfo; + + lsinfo = find_lockspace(iminor(inode)); + if (!lsinfo) + return -ENOENT; + + f = kmalloc(sizeof(struct file_info), GFP_KERNEL); + if (!f) + return -ENOMEM; + + atomic_inc(&lsinfo->ls_refcnt); + INIT_LIST_HEAD(&f->fi_li_list); + INIT_LIST_HEAD(&f->fi_ast_list); + spin_lock_init(&f->fi_li_lock); + spin_lock_init(&f->fi_ast_lock); + init_waitqueue_head(&f->fi_wait); + f->fi_ls = lsinfo; + f->fi_flags = 0; + get_file_info(f); + set_bit(1, &f->fi_flags); + + file->private_data = f; + + return 0; +} + +/* Check the user's version matches ours */ +static int check_version(struct dlm_write_request *req) +{ + if (req->version[0] != DLM_DEVICE_VERSION_MAJOR || + (req->version[0] == DLM_DEVICE_VERSION_MAJOR && + req->version[1] > DLM_DEVICE_VERSION_MINOR)) { + + printk(KERN_DEBUG "dlm: process %s (%d) version mismatch " + "user (%d.%d.%d) kernel (%d.%d.%d)\n", + current->comm, + current->pid, + req->version[0], + req->version[1], + req->version[2], + DLM_DEVICE_VERSION_MAJOR, + DLM_DEVICE_VERSION_MINOR, + DLM_DEVICE_VERSION_PATCH); + return -EINVAL; + } + return 0; +} + +/* Close on lockspace device */ +static int dlm_close(struct inode *inode, struct file *file) +{ + struct file_info *f = file->private_data; + struct lock_info li; + struct lock_info *old_li, *safe; + sigset_t tmpsig; + sigset_t allsigs; + struct user_ls *lsinfo; + DECLARE_WAITQUEUE(wq, current); + + lsinfo = find_lockspace(iminor(inode)); + if (!lsinfo) + return -ENOENT; + + /* Mark this closed so that ASTs will not be delivered any more */ + clear_bit(1, &f->fi_flags); + + /* Block signals while we are doing this */ + sigfillset(&allsigs); + sigprocmask(SIG_BLOCK, &allsigs, &tmpsig); + + /* We use our own lock_info struct here, so that any + * outstanding "real" ASTs will be delivered with the + * corresponding "real" params, thus freeing the lock_info + * that belongs the lock. This catches the corner case where + * a lock is BUSY when we try to unlock it here + */ + memset(&li, 0, sizeof(li)); + clear_bit(LI_FLAG_COMPLETE, &li.li_flags); + init_waitqueue_head(&li.li_waitq); + add_wait_queue(&li.li_waitq, &wq); + + /* + * Free any outstanding locks, they are on the + * list in LIFO order so there should be no problems + * about unlocking parents before children. + */ + list_for_each_entry_safe(old_li, safe, &f->fi_li_list, li_ownerqueue) { + int status; + int flags = 0; + + /* Don't unlock persistent locks, just mark them orphaned */ + if (test_bit(LI_FLAG_PERSISTENT, &old_li->li_flags)) { + list_del(&old_li->li_ownerqueue); + + /* Update master copy */ + /* TODO: Check locking core updates the local and + remote ORPHAN flags */ + li.li_lksb.sb_lkid = old_li->li_lksb.sb_lkid; + status = dlm_lock(f->fi_ls->ls_lockspace, + old_li->li_grmode, &li.li_lksb, + DLM_LKF_CONVERT|DLM_LKF_ORPHAN, + NULL, 0, 0, ast_routine, NULL, + NULL, NULL); + if (status != 0) + printk("dlm: Error orphaning lock %x: %d\n", + old_li->li_lksb.sb_lkid, status); + + /* But tidy our references in it */ + release_lockinfo(old_li); + continue; + } + + clear_bit(LI_FLAG_COMPLETE, &li.li_flags); + + flags = DLM_LKF_FORCEUNLOCK; + if (old_li->li_grmode >= DLM_LOCK_PW) + flags |= DLM_LKF_IVVALBLK; + + status = dlm_unlock(f->fi_ls->ls_lockspace, + old_li->li_lksb.sb_lkid, flags, + &li.li_lksb, &li); + + /* Must wait for it to complete as the next lock could be its + * parent */ + if (status == 0) + wait_for_ast(&li); + + /* Unlock suceeded, free the lock_info struct. */ + if (status == 0) + release_lockinfo(old_li); + } + + remove_wait_queue(&li.li_waitq, &wq); + + /* + * If this is the last reference to the lockspace + * then free the struct. If it's an AUTOFREE lockspace + * then free the whole thing. + */ + down(&user_ls_lock); + if (atomic_dec_and_test(&lsinfo->ls_refcnt)) { + + if (lsinfo->ls_lockspace) { + if (test_bit(LS_FLAG_AUTOFREE, &lsinfo->ls_flags)) { + unregister_lockspace(lsinfo, 1); + } + } else { + kfree(lsinfo->ls_miscinfo.name); + kfree(lsinfo); + } + } + up(&user_ls_lock); + put_file_info(f); + + /* Restore signals */ + sigprocmask(SIG_SETMASK, &tmpsig, NULL); + recalc_sigpending(); + + return 0; +} + +static int do_user_create_lockspace(struct file_info *fi, uint8_t cmd, + struct dlm_lspace_params *kparams) +{ + int status; + struct user_ls *lsinfo; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + status = register_lockspace(kparams->name, &lsinfo, kparams->flags); + + /* If it succeeded then return the minor number */ + if (status == 0) + status = lsinfo->ls_miscinfo.minor; + + return status; +} + +static int do_user_remove_lockspace(struct file_info *fi, uint8_t cmd, + struct dlm_lspace_params *kparams) +{ + int status; + int force = 1; + struct user_ls *lsinfo; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + down(&user_ls_lock); + lsinfo = __find_lockspace(kparams->minor); + if (!lsinfo) { + up(&user_ls_lock); + return -EINVAL; + } + + if (kparams->flags & DLM_USER_LSFLG_FORCEFREE) + force = 2; + + status = unregister_lockspace(lsinfo, force); + up(&user_ls_lock); + + return status; +} + +/* Read call, might block if no ASTs are waiting. + * It will only ever return one message at a time, regardless + * of how many are pending. + */ +static ssize_t dlm_read(struct file *file, char __user *buffer, size_t count, + loff_t *ppos) +{ + struct file_info *fi = file->private_data; + struct ast_info *ast; + int data_size; + int offset; + DECLARE_WAITQUEUE(wait, current); + + if (count < sizeof(struct dlm_lock_result)) + return -EINVAL; + + spin_lock(&fi->fi_ast_lock); + if (list_empty(&fi->fi_ast_list)) { + + /* No waiting ASTs. + * Return EOF if the lockspace been deleted. + */ + if (test_bit(LS_FLAG_DELETED, &fi->fi_ls->ls_flags)) + return 0; + + if (file->f_flags & O_NONBLOCK) { + spin_unlock(&fi->fi_ast_lock); + return -EAGAIN; + } + + add_wait_queue(&fi->fi_wait, &wait); + + repeat: + set_current_state(TASK_INTERRUPTIBLE); + if (list_empty(&fi->fi_ast_list) && + !signal_pending(current)) { + + spin_unlock(&fi->fi_ast_lock); + schedule(); + spin_lock(&fi->fi_ast_lock); + goto repeat; + } + + current->state = TASK_RUNNING; + remove_wait_queue(&fi->fi_wait, &wait); + + if (signal_pending(current)) { + spin_unlock(&fi->fi_ast_lock); + return -ERESTARTSYS; + } + } + + ast = list_entry(fi->fi_ast_list.next, struct ast_info, list); + list_del(&ast->list); + spin_unlock(&fi->fi_ast_lock); + + /* Work out the size of the returned data */ + data_size = sizeof(struct dlm_lock_result); + if (ast->lvb_updated && ast->result.lksb.sb_lvbptr) + data_size += DLM_USER_LVB_LEN; + + offset = sizeof(struct dlm_lock_result); + + /* Room for the extended data ? */ + if (count >= data_size) { + + if (ast->lvb_updated && ast->result.lksb.sb_lvbptr) { + if (copy_to_user(buffer+offset, + ast->result.lksb.sb_lvbptr, + DLM_USER_LVB_LEN)) + return -EFAULT; + ast->result.lvb_offset = offset; + offset += DLM_USER_LVB_LEN; + } + } + + ast->result.length = data_size; + /* Copy the header now it has all the offsets in it */ + if (copy_to_user(buffer, &ast->result, sizeof(struct dlm_lock_result))) + offset = -EFAULT; + + /* If we only returned a header and there's more to come then put it + back on the list */ + if (count < data_size) { + spin_lock(&fi->fi_ast_lock); + list_add(&ast->list, &fi->fi_ast_list); + spin_unlock(&fi->fi_ast_lock); + } else + kfree(ast); + return offset; +} + +static unsigned int dlm_poll(struct file *file, poll_table *wait) +{ + struct file_info *fi = file->private_data; + + poll_wait(file, &fi->fi_wait, wait); + + spin_lock(&fi->fi_ast_lock); + if (!list_empty(&fi->fi_ast_list)) { + spin_unlock(&fi->fi_ast_lock); + return POLLIN | POLLRDNORM; + } + + spin_unlock(&fi->fi_ast_lock); + return 0; +} + +static struct lock_info *allocate_lockinfo(struct file_info *fi, uint8_t cmd, + struct dlm_lock_params *kparams) +{ + struct lock_info *li; + + if (!try_module_get(THIS_MODULE)) + return NULL; + + li = kmalloc(sizeof(struct lock_info), GFP_KERNEL); + if (li) { + li->li_magic = LOCKINFO_MAGIC; + li->li_file = fi; + li->li_cmd = cmd; + li->li_flags = 0; + li->li_grmode = -1; + li->li_rqmode = -1; + li->li_pend_bastparam = NULL; + li->li_pend_bastaddr = NULL; + li->li_castaddr = NULL; + li->li_castparam = NULL; + li->li_lksb.sb_lvbptr = NULL; + li->li_bastaddr = kparams->bastaddr; + li->li_bastparam = kparams->bastparam; + + get_file_info(fi); + } + return li; +} + +static int do_user_lock(struct file_info *fi, uint8_t cmd, + struct dlm_lock_params *kparams) +{ + struct lock_info *li; + int status; + + /* + * Validate things that we need to have correct. + */ + if (!kparams->castaddr) + return -EINVAL; + + if (!kparams->lksb) + return -EINVAL; + + /* Persistent child locks are not available yet */ + if ((kparams->flags & DLM_LKF_PERSISTENT) && kparams->parent) + return -EINVAL; + + /* For conversions, there should already be a lockinfo struct, + unless we are adopting an orphaned persistent lock */ + if (kparams->flags & DLM_LKF_CONVERT) { + + li = get_lockinfo(kparams->lkid); + + /* If this is a persistent lock we will have to create a + lockinfo again */ + if (!li && DLM_LKF_PERSISTENT) { + li = allocate_lockinfo(fi, cmd, kparams); + + li->li_lksb.sb_lkid = kparams->lkid; + li->li_castaddr = kparams->castaddr; + li->li_castparam = kparams->castparam; + + /* OK, this isn;t exactly a FIRSTLOCK but it is the + first time we've used this lockinfo, and if things + fail we want rid of it */ + init_MUTEX_LOCKED(&li->li_firstlock); + set_bit(LI_FLAG_FIRSTLOCK, &li->li_flags); + add_lockinfo(li); + + /* TODO: do a query to get the current state ?? */ + } + if (!li) + return -EINVAL; + + if (li->li_magic != LOCKINFO_MAGIC) + return -EINVAL; + + /* For conversions don't overwrite the current blocking AST + info so that: + a) if a blocking AST fires before the conversion is queued + it runs the current handler + b) if the conversion is cancelled, the original blocking AST + declaration is active + The pend_ info is made active when the conversion + completes. + */ + li->li_pend_bastaddr = kparams->bastaddr; + li->li_pend_bastparam = kparams->bastparam; + } else { + li = allocate_lockinfo(fi, cmd, kparams); + if (!li) + return -ENOMEM; + + /* semaphore to allow us to complete our work before + the AST routine runs. In fact we only need (and use) this + when the initial lock fails */ + init_MUTEX_LOCKED(&li->li_firstlock); + set_bit(LI_FLAG_FIRSTLOCK, &li->li_flags); + } + + li->li_user_lksb = kparams->lksb; + li->li_castaddr = kparams->castaddr; + li->li_castparam = kparams->castparam; + li->li_lksb.sb_lkid = kparams->lkid; + li->li_rqmode = kparams->mode; + if (kparams->flags & DLM_LKF_PERSISTENT) + set_bit(LI_FLAG_PERSISTENT, &li->li_flags); + + /* Copy in the value block */ + if (kparams->flags & DLM_LKF_VALBLK) { + if (!li->li_lksb.sb_lvbptr) { + li->li_lksb.sb_lvbptr = kmalloc(DLM_USER_LVB_LEN, + GFP_KERNEL); + if (!li->li_lksb.sb_lvbptr) { + status = -ENOMEM; + goto out_err; + } + } + + memcpy(li->li_lksb.sb_lvbptr, kparams->lvb, DLM_USER_LVB_LEN); + } + + /* Lock it ... */ + status = dlm_lock(fi->fi_ls->ls_lockspace, + kparams->mode, &li->li_lksb, + kparams->flags, + kparams->name, kparams->namelen, + kparams->parent, + ast_routine, + li, + (li->li_pend_bastaddr || li->li_bastaddr) ? + bast_routine : NULL, + kparams->range.ra_end ? &kparams->range : NULL); + if (status) + goto out_err; + + /* If it succeeded (this far) with a new lock then keep track of + it on the file's lockinfo list */ + if (!status && test_bit(LI_FLAG_FIRSTLOCK, &li->li_flags)) { + + spin_lock(&fi->fi_li_lock); + list_add(&li->li_ownerqueue, &fi->fi_li_list); + spin_unlock(&fi->fi_li_lock); + if (add_lockinfo(li)) + printk(KERN_WARNING "Add lockinfo failed\n"); + + up(&li->li_firstlock); + } + + /* Return the lockid as the user needs it /now/ */ + return li->li_lksb.sb_lkid; + + out_err: + if (test_bit(LI_FLAG_FIRSTLOCK, &li->li_flags)) + release_lockinfo(li); + return status; + +} + +static int do_user_unlock(struct file_info *fi, uint8_t cmd, + struct dlm_lock_params *kparams) +{ + struct lock_info *li; + int status; + int convert_cancel = 0; + + li = get_lockinfo(kparams->lkid); + if (!li) { + li = allocate_lockinfo(fi, cmd, kparams); + spin_lock(&fi->fi_li_lock); + list_add(&li->li_ownerqueue, &fi->fi_li_list); + spin_unlock(&fi->fi_li_lock); + } + if (!li) + return -ENOMEM; + + if (li->li_magic != LOCKINFO_MAGIC) + return -EINVAL; + + li->li_user_lksb = kparams->lksb; + li->li_castparam = kparams->castparam; + li->li_cmd = cmd; + + /* Cancelling a conversion doesn't remove the lock...*/ + if (kparams->flags & DLM_LKF_CANCEL && li->li_grmode != -1) + convert_cancel = 1; + + /* dlm_unlock() passes a 0 for castaddr which means don't overwrite + the existing li_castaddr as that's the completion routine for + unlocks. dlm_unlock_wait() specifies a new AST routine to be + executed when the unlock completes. */ + if (kparams->castaddr) + li->li_castaddr = kparams->castaddr; + + /* Use existing lksb & astparams */ + status = dlm_unlock(fi->fi_ls->ls_lockspace, + kparams->lkid, + kparams->flags, &li->li_lksb, li); + + if (!status && !convert_cancel) { + spin_lock(&fi->fi_li_lock); + list_del(&li->li_ownerqueue); + spin_unlock(&fi->fi_li_lock); + } + + return status; +} + +/* Write call, submit a locking request */ +static ssize_t dlm_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) +{ + struct file_info *fi = file->private_data; + struct dlm_write_request *kparams; + sigset_t tmpsig; + sigset_t allsigs; + int status; + + /* -1 because lock name is optional */ + if (count < sizeof(struct dlm_write_request)-1) + return -EINVAL; + + /* Has the lockspace been deleted */ + if (fi && test_bit(LS_FLAG_DELETED, &fi->fi_ls->ls_flags)) + return -ENOENT; + + kparams = kmalloc(count, GFP_KERNEL); + if (!kparams) + return -ENOMEM; + + status = -EFAULT; + /* Get the command info */ + if (copy_from_user(kparams, buffer, count)) + goto out_free; + + status = -EBADE; + if (check_version(kparams)) + goto out_free; + + /* Block signals while we are doing this */ + sigfillset(&allsigs); + sigprocmask(SIG_BLOCK, &allsigs, &tmpsig); + + status = -EINVAL; + switch (kparams->cmd) + { + case DLM_USER_LOCK: + if (!fi) goto out_sig; + status = do_user_lock(fi, kparams->cmd, &kparams->i.lock); + break; + + case DLM_USER_UNLOCK: + if (!fi) goto out_sig; + status = do_user_unlock(fi, kparams->cmd, &kparams->i.lock); + break; + + case DLM_USER_CREATE_LOCKSPACE: + if (fi) goto out_sig; + status = do_user_create_lockspace(fi, kparams->cmd, + &kparams->i.lspace); + break; + + case DLM_USER_REMOVE_LOCKSPACE: + if (fi) goto out_sig; + status = do_user_remove_lockspace(fi, kparams->cmd, + &kparams->i.lspace); + break; + default: + printk("Unknown command passed to DLM device : %d\n", + kparams->cmd); + break; + } + + out_sig: + /* Restore signals */ + sigprocmask(SIG_SETMASK, &tmpsig, NULL); + recalc_sigpending(); + + out_free: + kfree(kparams); + if (status == 0) + return count; + else + return status; +} + +static struct file_operations _dlm_fops = { + .open = dlm_open, + .release = dlm_close, + .read = dlm_read, + .write = dlm_write, + .poll = dlm_poll, + .owner = THIS_MODULE, +}; + +static struct file_operations _dlm_ctl_fops = { + .open = dlm_ctl_open, + .release = dlm_ctl_close, + .write = dlm_write, + .owner = THIS_MODULE, +}; + +/* + * Create control device + */ +static int __init dlm_device_init(void) +{ + int r; + + INIT_LIST_HEAD(&user_ls_list); + init_MUTEX(&user_ls_lock); + rwlock_init(&lockinfo_lock); + + ctl_device.name = "dlm-control"; + ctl_device.fops = &_dlm_ctl_fops; + ctl_device.minor = MISC_DYNAMIC_MINOR; + + r = misc_register(&ctl_device); + if (r) { + printk(KERN_ERR "dlm: misc_register failed for control dev\n"); + return r; + } + + return 0; +} + +static void __exit dlm_device_exit(void) +{ + misc_deregister(&ctl_device); +} + +MODULE_DESCRIPTION("Distributed Lock Manager device interface"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); + +module_init(dlm_device_init); +module_exit(dlm_device_exit); diff --git a/fs/dlm/dir.c b/fs/dlm/dir.c new file mode 100644 index 000000000000..0f1dde54bcd2 --- /dev/null +++ b/fs/dlm/dir.c @@ -0,0 +1,423 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "member.h" +#include "lowcomms.h" +#include "rcom.h" +#include "config.h" +#include "memory.h" +#include "recover.h" +#include "util.h" +#include "lock.h" +#include "dir.h" + + +static void put_free_de(struct dlm_ls *ls, struct dlm_direntry *de) +{ + spin_lock(&ls->ls_recover_list_lock); + list_add(&de->list, &ls->ls_recover_list); + spin_unlock(&ls->ls_recover_list_lock); +} + +static struct dlm_direntry *get_free_de(struct dlm_ls *ls, int len) +{ + int found = FALSE; + struct dlm_direntry *de; + + spin_lock(&ls->ls_recover_list_lock); + list_for_each_entry(de, &ls->ls_recover_list, list) { + if (de->length == len) { + list_del(&de->list); + de->master_nodeid = 0; + memset(de->name, 0, len); + found = TRUE; + break; + } + } + spin_unlock(&ls->ls_recover_list_lock); + + if (!found) + de = allocate_direntry(ls, len); + return de; +} + +void dlm_clear_free_entries(struct dlm_ls *ls) +{ + struct dlm_direntry *de; + + spin_lock(&ls->ls_recover_list_lock); + while (!list_empty(&ls->ls_recover_list)) { + de = list_entry(ls->ls_recover_list.next, struct dlm_direntry, + list); + list_del(&de->list); + free_direntry(de); + } + spin_unlock(&ls->ls_recover_list_lock); +} + +/* + * We use the upper 16 bits of the hash value to select the directory node. + * Low bits are used for distribution of rsb's among hash buckets on each node. + * + * To give the exact range wanted (0 to num_nodes-1), we apply a modulus of + * num_nodes to the hash value. This value in the desired range is used as an + * offset into the sorted list of nodeid's to give the particular nodeid. + */ + +int dlm_hash2nodeid(struct dlm_ls *ls, uint32_t hash) +{ + struct list_head *tmp; + struct dlm_member *memb = NULL; + uint32_t node, n = 0; + int nodeid; + + if (ls->ls_num_nodes == 1) { + nodeid = dlm_our_nodeid(); + goto out; + } + + if (ls->ls_node_array) { + node = (hash >> 16) % ls->ls_total_weight; + nodeid = ls->ls_node_array[node]; + goto out; + } + + /* make_member_array() failed to kmalloc ls_node_array... */ + + node = (hash >> 16) % ls->ls_num_nodes; + + list_for_each(tmp, &ls->ls_nodes) { + if (n++ != node) + continue; + memb = list_entry(tmp, struct dlm_member, list); + break; + } + + DLM_ASSERT(memb , printk("num_nodes=%u n=%u node=%u\n", + ls->ls_num_nodes, n, node);); + nodeid = memb->nodeid; + out: + return nodeid; +} + +int dlm_dir_nodeid(struct dlm_rsb *r) +{ + return dlm_hash2nodeid(r->res_ls, r->res_hash); +} + +static inline uint32_t dir_hash(struct dlm_ls *ls, char *name, int len) +{ + uint32_t val; + + val = jhash(name, len, 0); + val &= (ls->ls_dirtbl_size - 1); + + return val; +} + +static void add_entry_to_hash(struct dlm_ls *ls, struct dlm_direntry *de) +{ + uint32_t bucket; + + bucket = dir_hash(ls, de->name, de->length); + list_add_tail(&de->list, &ls->ls_dirtbl[bucket].list); +} + +static struct dlm_direntry *search_bucket(struct dlm_ls *ls, char *name, + int namelen, uint32_t bucket) +{ + struct dlm_direntry *de; + + list_for_each_entry(de, &ls->ls_dirtbl[bucket].list, list) { + if (de->length == namelen && !memcmp(name, de->name, namelen)) + goto out; + } + de = NULL; + out: + return de; +} + +void dlm_dir_remove_entry(struct dlm_ls *ls, int nodeid, char *name, int namelen) +{ + struct dlm_direntry *de; + uint32_t bucket; + + bucket = dir_hash(ls, name, namelen); + + write_lock(&ls->ls_dirtbl[bucket].lock); + + de = search_bucket(ls, name, namelen, bucket); + + if (!de) { + log_error(ls, "remove fr %u none", nodeid); + goto out; + } + + if (de->master_nodeid != nodeid) { + log_error(ls, "remove fr %u ID %u", nodeid, de->master_nodeid); + goto out; + } + + list_del(&de->list); + free_direntry(de); + out: + write_unlock(&ls->ls_dirtbl[bucket].lock); +} + +void dlm_dir_clear(struct dlm_ls *ls) +{ + struct list_head *head; + struct dlm_direntry *de; + int i; + + DLM_ASSERT(list_empty(&ls->ls_recover_list), ); + + for (i = 0; i < ls->ls_dirtbl_size; i++) { + write_lock(&ls->ls_dirtbl[i].lock); + head = &ls->ls_dirtbl[i].list; + while (!list_empty(head)) { + de = list_entry(head->next, struct dlm_direntry, list); + list_del(&de->list); + put_free_de(ls, de); + } + write_unlock(&ls->ls_dirtbl[i].lock); + } +} + +int dlm_recover_directory(struct dlm_ls *ls) +{ + struct dlm_member *memb; + struct dlm_direntry *de; + char *b, *last_name = NULL; + int error = -ENOMEM, last_len, count = 0; + uint16_t namelen; + + log_debug(ls, "dlm_recover_directory"); + + if (dlm_no_directory(ls)) + goto out_status; + + dlm_dir_clear(ls); + + last_name = kmalloc(DLM_RESNAME_MAXLEN, GFP_KERNEL); + if (!last_name) + goto out; + + list_for_each_entry(memb, &ls->ls_nodes, list) { + memset(last_name, 0, DLM_RESNAME_MAXLEN); + last_len = 0; + + for (;;) { + error = dlm_recovery_stopped(ls); + if (error) + goto out_free; + + error = dlm_rcom_names(ls, memb->nodeid, + last_name, last_len); + if (error) + goto out_free; + + schedule(); + + /* + * pick namelen/name pairs out of received buffer + */ + + b = ls->ls_recover_buf + sizeof(struct dlm_rcom); + + for (;;) { + memcpy(&namelen, b, sizeof(uint16_t)); + namelen = be16_to_cpu(namelen); + b += sizeof(uint16_t); + + /* namelen of 0xFFFFF marks end of names for + this node; namelen of 0 marks end of the + buffer */ + + if (namelen == 0xFFFF) + goto done; + if (!namelen) + break; + + error = -ENOMEM; + de = get_free_de(ls, namelen); + if (!de) + goto out_free; + + de->master_nodeid = memb->nodeid; + de->length = namelen; + last_len = namelen; + memcpy(de->name, b, namelen); + memcpy(last_name, b, namelen); + b += namelen; + + add_entry_to_hash(ls, de); + count++; + } + } + done: + ; + } + + out_status: + error = 0; + dlm_set_recover_status(ls, DLM_RS_DIR); + log_debug(ls, "dlm_recover_directory %d entries", count); + out_free: + kfree(last_name); + out: + dlm_clear_free_entries(ls); + return error; +} + +static int get_entry(struct dlm_ls *ls, int nodeid, char *name, + int namelen, int *r_nodeid) +{ + struct dlm_direntry *de, *tmp; + uint32_t bucket; + + bucket = dir_hash(ls, name, namelen); + + write_lock(&ls->ls_dirtbl[bucket].lock); + de = search_bucket(ls, name, namelen, bucket); + if (de) { + *r_nodeid = de->master_nodeid; + write_unlock(&ls->ls_dirtbl[bucket].lock); + if (*r_nodeid == nodeid) + return -EEXIST; + return 0; + } + + write_unlock(&ls->ls_dirtbl[bucket].lock); + + de = allocate_direntry(ls, namelen); + if (!de) + return -ENOMEM; + + de->master_nodeid = nodeid; + de->length = namelen; + memcpy(de->name, name, namelen); + + write_lock(&ls->ls_dirtbl[bucket].lock); + tmp = search_bucket(ls, name, namelen, bucket); + if (tmp) { + free_direntry(de); + de = tmp; + } else { + list_add_tail(&de->list, &ls->ls_dirtbl[bucket].list); + } + *r_nodeid = de->master_nodeid; + write_unlock(&ls->ls_dirtbl[bucket].lock); + return 0; +} + +int dlm_dir_lookup(struct dlm_ls *ls, int nodeid, char *name, int namelen, + int *r_nodeid) +{ + return get_entry(ls, nodeid, name, namelen, r_nodeid); +} + +/* Copy the names of master rsb's into the buffer provided. + Only select names whose dir node is the given nodeid. */ + +void dlm_copy_master_names(struct dlm_ls *ls, char *inbuf, int inlen, + char *outbuf, int outlen, int nodeid) +{ + struct list_head *list; + struct dlm_rsb *start_r = NULL, *r = NULL; + int offset = 0, start_namelen, error, dir_nodeid; + char *start_name; + uint16_t be_namelen; + + /* + * Find the rsb where we left off (or start again) + */ + + start_namelen = inlen; + start_name = inbuf; + + if (start_namelen > 1) { + /* + * We could also use a find_rsb_root() function here that + * searched the ls_root_list. + */ + error = dlm_find_rsb(ls, start_name, start_namelen, R_MASTER, + &start_r); + DLM_ASSERT(!error && start_r, + printk("error %d\n", error);); + DLM_ASSERT(!list_empty(&start_r->res_root_list), + dlm_print_rsb(start_r);); + dlm_put_rsb(start_r); + } + + /* + * Send rsb names for rsb's we're master of and whose directory node + * matches the requesting node. + */ + + down_read(&ls->ls_root_sem); + if (start_r) + list = start_r->res_root_list.next; + else + list = ls->ls_root_list.next; + + for (offset = 0; list != &ls->ls_root_list; list = list->next) { + r = list_entry(list, struct dlm_rsb, res_root_list); + if (r->res_nodeid) + continue; + + dir_nodeid = dlm_dir_nodeid(r); + if (dir_nodeid != nodeid) + continue; + + /* + * The block ends when we can't fit the following in the + * remaining buffer space: + * namelen (uint16_t) + + * name (r->res_length) + + * end-of-block record 0x0000 (uint16_t) + */ + + if (offset + sizeof(uint16_t)*2 + r->res_length > outlen) { + /* Write end-of-block record */ + be_namelen = 0; + memcpy(outbuf + offset, &be_namelen, sizeof(uint16_t)); + offset += sizeof(uint16_t); + goto out; + } + + be_namelen = cpu_to_be16(r->res_length); + memcpy(outbuf + offset, &be_namelen, sizeof(uint16_t)); + offset += sizeof(uint16_t); + memcpy(outbuf + offset, r->res_name, r->res_length); + offset += r->res_length; + } + + /* + * If we've reached the end of the list (and there's room) write a + * terminating record. + */ + + if ((list == &ls->ls_root_list) && + (offset + sizeof(uint16_t) <= outlen)) { + be_namelen = 0xFFFF; + memcpy(outbuf + offset, &be_namelen, sizeof(uint16_t)); + offset += sizeof(uint16_t); + } + + out: + up_read(&ls->ls_root_sem); +} + diff --git a/fs/dlm/dir.h b/fs/dlm/dir.h new file mode 100644 index 000000000000..0b0eb1267b6e --- /dev/null +++ b/fs/dlm/dir.h @@ -0,0 +1,30 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __DIR_DOT_H__ +#define __DIR_DOT_H__ + + +int dlm_dir_nodeid(struct dlm_rsb *rsb); +int dlm_hash2nodeid(struct dlm_ls *ls, uint32_t hash); +void dlm_dir_remove_entry(struct dlm_ls *ls, int nodeid, char *name, int len); +void dlm_dir_clear(struct dlm_ls *ls); +void dlm_clear_free_entries(struct dlm_ls *ls); +int dlm_recover_directory(struct dlm_ls *ls); +int dlm_dir_lookup(struct dlm_ls *ls, int nodeid, char *name, int namelen, + int *r_nodeid); +void dlm_copy_master_names(struct dlm_ls *ls, char *inbuf, int inlen, + char *outbuf, int outlen, int nodeid); + +#endif /* __DIR_DOT_H__ */ + diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h new file mode 100644 index 000000000000..0020cd07baf7 --- /dev/null +++ b/fs/dlm/dlm_internal.h @@ -0,0 +1,518 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __DLM_INTERNAL_DOT_H__ +#define __DLM_INTERNAL_DOT_H__ + +/* + * This is the main header file to be included in each DLM source file. + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/types.h> +#include <linux/ctype.h> +#include <linux/spinlock.h> +#include <linux/vmalloc.h> +#include <linux/list.h> +#include <linux/errno.h> +#include <linux/random.h> +#include <linux/delay.h> +#include <linux/socket.h> +#include <linux/kthread.h> +#include <linux/kobject.h> +#include <linux/kref.h> +#include <linux/kernel.h> +#include <linux/jhash.h> +#include <asm/semaphore.h> +#include <asm/uaccess.h> + +#include <linux/dlm.h> + +#define DLM_LOCKSPACE_LEN 64 + +#ifndef TRUE +#define TRUE 1 +#endif + +#ifndef FALSE +#define FALSE 0 +#endif + +#if (BITS_PER_LONG == 64) +#define PRIx64 "lx" +#else +#define PRIx64 "Lx" +#endif + +/* Size of the temp buffer midcomms allocates on the stack. + We try to make this large enough so most messages fit. + FIXME: should sctp make this unnecessary? */ + +#define DLM_INBUF_LEN 148 + +struct dlm_ls; +struct dlm_lkb; +struct dlm_rsb; +struct dlm_member; +struct dlm_lkbtable; +struct dlm_rsbtable; +struct dlm_dirtable; +struct dlm_direntry; +struct dlm_recover; +struct dlm_header; +struct dlm_message; +struct dlm_rcom; +struct dlm_mhandle; + +#define log_print(fmt, args...) \ + printk(KERN_ERR "dlm: "fmt"\n" , ##args) +#define log_error(ls, fmt, args...) \ + printk(KERN_ERR "dlm: %s: " fmt "\n", (ls)->ls_name , ##args) + +#ifdef DLM_LOG_DEBUG +#define log_debug(ls, fmt, args...) log_error(ls, fmt, ##args) +#else +#define log_debug(ls, fmt, args...) +#endif + +#define DLM_ASSERT(x, do) \ +{ \ + if (!(x)) \ + { \ + printk(KERN_ERR "\nDLM: Assertion failed on line %d of file %s\n" \ + "DLM: assertion: \"%s\"\n" \ + "DLM: time = %lu\n", \ + __LINE__, __FILE__, #x, jiffies); \ + {do} \ + printk("\n"); \ + BUG(); \ + panic("DLM: Record message above and reboot.\n"); \ + } \ +} + + +struct dlm_direntry { + struct list_head list; + uint32_t master_nodeid; + uint16_t length; + char name[1]; +}; + +struct dlm_dirtable { + struct list_head list; + rwlock_t lock; +}; + +struct dlm_rsbtable { + struct list_head list; + struct list_head toss; + rwlock_t lock; +}; + +struct dlm_lkbtable { + struct list_head list; + rwlock_t lock; + uint16_t counter; +}; + +/* + * Lockspace member (per node in a ls) + */ + +struct dlm_member { + struct list_head list; + int nodeid; + int weight; +}; + +/* + * Save and manage recovery state for a lockspace. + */ + +struct dlm_recover { + struct list_head list; + int *nodeids; + int node_count; + uint64_t seq; +}; + +/* + * Pass input args to second stage locking function. + */ + +struct dlm_args { + uint32_t flags; + void *astaddr; + long astparam; + void *bastaddr; + int mode; + struct dlm_lksb *lksb; + struct dlm_range *range; +}; + + +/* + * Lock block + * + * A lock can be one of three types: + * + * local copy lock is mastered locally + * (lkb_nodeid is zero and DLM_LKF_MSTCPY is not set) + * process copy lock is mastered on a remote node + * (lkb_nodeid is non-zero and DLM_LKF_MSTCPY is not set) + * master copy master node's copy of a lock owned by remote node + * (lkb_nodeid is non-zero and DLM_LKF_MSTCPY is set) + * + * lkb_exflags: a copy of the most recent flags arg provided to dlm_lock or + * dlm_unlock. The dlm does not modify these or use any private flags in + * this field; it only contains DLM_LKF_ flags from dlm.h. These flags + * are sent as-is to the remote master when the lock is remote. + * + * lkb_flags: internal dlm flags (DLM_IFL_ prefix) from dlm_internal.h. + * Some internal flags are shared between the master and process nodes; + * these shared flags are kept in the lower two bytes. One of these + * flags set on the master copy will be propagated to the process copy + * and v.v. Other internal flags are private to the master or process + * node (e.g. DLM_IFL_MSTCPY). These are kept in the high two bytes. + * + * lkb_sbflags: status block flags. These flags are copied directly into + * the caller's lksb.sb_flags prior to the dlm_lock/dlm_unlock completion + * ast. All defined in dlm.h with DLM_SBF_ prefix. + * + * lkb_status: the lock status indicates which rsb queue the lock is + * on, grant, convert, or wait. DLM_LKSTS_ WAITING/GRANTED/CONVERT + * + * lkb_wait_type: the dlm message type (DLM_MSG_ prefix) for which a + * reply is needed. Only set when the lkb is on the lockspace waiters + * list awaiting a reply from a remote node. + * + * lkb_nodeid: when the lkb is a local copy, nodeid is 0; when the lkb + * is a master copy, nodeid specifies the remote lock holder, when the + * lkb is a process copy, the nodeid specifies the lock master. + */ + +/* lkb_ast_type */ + +#define AST_COMP 1 +#define AST_BAST 2 + +/* lkb_range[] */ + +#define GR_RANGE_START 0 +#define GR_RANGE_END 1 +#define RQ_RANGE_START 2 +#define RQ_RANGE_END 3 + +/* lkb_status */ + +#define DLM_LKSTS_WAITING 1 +#define DLM_LKSTS_GRANTED 2 +#define DLM_LKSTS_CONVERT 3 + +/* lkb_flags */ + +#define DLM_IFL_MSTCPY 0x00010000 +#define DLM_IFL_RESEND 0x00020000 +#define DLM_IFL_RANGE 0x00000001 + +struct dlm_lkb { + struct dlm_rsb *lkb_resource; /* the rsb */ + struct kref lkb_ref; + int lkb_nodeid; /* copied from rsb */ + int lkb_ownpid; /* pid of lock owner */ + uint32_t lkb_id; /* our lock ID */ + uint32_t lkb_remid; /* lock ID on remote partner */ + uint32_t lkb_exflags; /* external flags from caller */ + uint32_t lkb_sbflags; /* lksb flags */ + uint32_t lkb_flags; /* internal flags */ + uint32_t lkb_lvbseq; /* lvb sequence number */ + + int8_t lkb_status; /* granted, waiting, convert */ + int8_t lkb_rqmode; /* requested lock mode */ + int8_t lkb_grmode; /* granted lock mode */ + int8_t lkb_bastmode; /* requested mode */ + int8_t lkb_highbast; /* highest mode bast sent for */ + + int8_t lkb_wait_type; /* type of reply waiting for */ + int8_t lkb_ast_type; /* type of ast queued for */ + + struct list_head lkb_idtbl_list; /* lockspace lkbtbl */ + struct list_head lkb_statequeue; /* rsb g/c/w list */ + struct list_head lkb_rsb_lookup; /* waiting for rsb lookup */ + struct list_head lkb_wait_reply; /* waiting for remote reply */ + struct list_head lkb_astqueue; /* need ast to be sent */ + + uint64_t *lkb_range; /* array of gr/rq ranges */ + char *lkb_lvbptr; + struct dlm_lksb *lkb_lksb; /* caller's status block */ + void *lkb_astaddr; /* caller's ast function */ + void *lkb_bastaddr; /* caller's bast function */ + long lkb_astparam; /* caller's ast arg */ +}; + + +struct dlm_rsb { + struct dlm_ls *res_ls; /* the lockspace */ + struct kref res_ref; + struct semaphore res_sem; + unsigned long res_flags; + int res_length; /* length of rsb name */ + int res_nodeid; + uint32_t res_lvbseq; + uint32_t res_hash; + uint32_t res_bucket; /* rsbtbl */ + unsigned long res_toss_time; + uint32_t res_first_lkid; + struct list_head res_lookup; /* lkbs waiting on first */ + struct list_head res_hashchain; /* rsbtbl */ + struct list_head res_grantqueue; + struct list_head res_convertqueue; + struct list_head res_waitqueue; + + struct list_head res_root_list; /* used for recovery */ + struct list_head res_recover_list; /* used for recovery */ + int res_recover_locks_count; + + char *res_lvbptr; + char res_name[1]; +}; + +/* find_rsb() flags */ + +#define R_MASTER 1 /* only return rsb if it's a master */ +#define R_CREATE 2 /* create/add rsb if not found */ + +/* rsb_flags */ + +enum rsb_flags { + RSB_MASTER_UNCERTAIN, + RSB_VALNOTVALID, + RSB_VALNOTVALID_PREV, + RSB_NEW_MASTER, + RSB_NEW_MASTER2, + RSB_RECOVER_CONVERT, +}; + +static inline void rsb_set_flag(struct dlm_rsb *r, enum rsb_flags flag) +{ + __set_bit(flag, &r->res_flags); +} + +static inline void rsb_clear_flag(struct dlm_rsb *r, enum rsb_flags flag) +{ + __clear_bit(flag, &r->res_flags); +} + +static inline int rsb_flag(struct dlm_rsb *r, enum rsb_flags flag) +{ + return test_bit(flag, &r->res_flags); +} + + +/* dlm_header is first element of all structs sent between nodes */ + +#define DLM_HEADER_MAJOR 0x00020000 +#define DLM_HEADER_MINOR 0x00000001 + +#define DLM_MSG 1 +#define DLM_RCOM 2 + +struct dlm_header { + uint32_t h_version; + uint32_t h_lockspace; + uint32_t h_nodeid; /* nodeid of sender */ + uint16_t h_length; + uint8_t h_cmd; /* DLM_MSG, DLM_RCOM */ + uint8_t h_pad; +}; + + +#define DLM_MSG_REQUEST 1 +#define DLM_MSG_CONVERT 2 +#define DLM_MSG_UNLOCK 3 +#define DLM_MSG_CANCEL 4 +#define DLM_MSG_REQUEST_REPLY 5 +#define DLM_MSG_CONVERT_REPLY 6 +#define DLM_MSG_UNLOCK_REPLY 7 +#define DLM_MSG_CANCEL_REPLY 8 +#define DLM_MSG_GRANT 9 +#define DLM_MSG_BAST 10 +#define DLM_MSG_LOOKUP 11 +#define DLM_MSG_REMOVE 12 +#define DLM_MSG_LOOKUP_REPLY 13 + +struct dlm_message { + struct dlm_header m_header; + uint32_t m_type; /* DLM_MSG_ */ + uint32_t m_nodeid; + uint32_t m_pid; + uint32_t m_lkid; /* lkid on sender */ + uint32_t m_remid; /* lkid on receiver */ + uint32_t m_parent_lkid; + uint32_t m_parent_remid; + uint32_t m_exflags; + uint32_t m_sbflags; + uint32_t m_flags; + uint32_t m_lvbseq; + uint32_t m_hash; + int m_status; + int m_grmode; + int m_rqmode; + int m_bastmode; + int m_asts; + int m_result; /* 0 or -EXXX */ + uint64_t m_range[2]; + char m_extra[0]; /* name or lvb */ +}; + + +#define DLM_RS_NODES 0x00000001 +#define DLM_RS_NODES_ALL 0x00000002 +#define DLM_RS_DIR 0x00000004 +#define DLM_RS_DIR_ALL 0x00000008 +#define DLM_RS_LOCKS 0x00000010 +#define DLM_RS_LOCKS_ALL 0x00000020 +#define DLM_RS_DONE 0x00000040 +#define DLM_RS_DONE_ALL 0x00000080 + +#define DLM_RCOM_STATUS 1 +#define DLM_RCOM_NAMES 2 +#define DLM_RCOM_LOOKUP 3 +#define DLM_RCOM_LOCK 4 +#define DLM_RCOM_STATUS_REPLY 5 +#define DLM_RCOM_NAMES_REPLY 6 +#define DLM_RCOM_LOOKUP_REPLY 7 +#define DLM_RCOM_LOCK_REPLY 8 + +struct dlm_rcom { + struct dlm_header rc_header; + uint32_t rc_type; /* DLM_RCOM_ */ + int rc_result; /* multi-purpose */ + uint64_t rc_id; /* match reply with request */ + char rc_buf[0]; +}; + +struct rcom_config { + uint32_t rf_lvblen; + uint32_t rf_lsflags; + uint64_t rf_unused; +}; + +struct rcom_lock { + uint32_t rl_ownpid; + uint32_t rl_lkid; + uint32_t rl_remid; + uint32_t rl_parent_lkid; + uint32_t rl_parent_remid; + uint32_t rl_exflags; + uint32_t rl_flags; + uint32_t rl_lvbseq; + int rl_result; + int8_t rl_rqmode; + int8_t rl_grmode; + int8_t rl_status; + int8_t rl_asts; + uint16_t rl_wait_type; + uint16_t rl_namelen; + uint64_t rl_range[4]; + char rl_name[DLM_RESNAME_MAXLEN]; + char rl_lvb[0]; +}; + +struct dlm_ls { + struct list_head ls_list; /* list of lockspaces */ + uint32_t ls_global_id; /* global unique lockspace ID */ + uint32_t ls_exflags; + int ls_lvblen; + int ls_count; /* reference count */ + unsigned long ls_flags; /* LSFL_ */ + struct kobject ls_kobj; + + struct dlm_rsbtable *ls_rsbtbl; + uint32_t ls_rsbtbl_size; + + struct dlm_lkbtable *ls_lkbtbl; + uint32_t ls_lkbtbl_size; + + struct dlm_dirtable *ls_dirtbl; + uint32_t ls_dirtbl_size; + + struct semaphore ls_waiters_sem; + struct list_head ls_waiters; /* lkbs needing a reply */ + + struct list_head ls_nodes; /* current nodes in ls */ + struct list_head ls_nodes_gone; /* dead node list, recovery */ + int ls_num_nodes; /* number of nodes in ls */ + int ls_low_nodeid; + int ls_total_weight; + int *ls_node_array; + + struct dlm_rsb ls_stub_rsb; /* for returning errors */ + struct dlm_lkb ls_stub_lkb; /* for returning errors */ + struct dlm_message ls_stub_ms; /* for faking a reply */ + + struct dentry *ls_debug_dentry; /* debugfs */ + + wait_queue_head_t ls_uevent_wait; /* user part of join/leave */ + int ls_uevent_result; + + /* recovery related */ + + struct timer_list ls_timer; + struct task_struct *ls_recoverd_task; + struct semaphore ls_recoverd_active; + spinlock_t ls_recover_lock; + uint32_t ls_recover_status; /* DLM_RS_ */ + uint64_t ls_recover_seq; + struct dlm_recover *ls_recover_args; + struct rw_semaphore ls_in_recovery; /* block local requests */ + struct list_head ls_requestqueue;/* queue remote requests */ + struct semaphore ls_requestqueue_lock; + char *ls_recover_buf; + struct list_head ls_recover_list; + spinlock_t ls_recover_list_lock; + int ls_recover_list_count; + wait_queue_head_t ls_wait_general; + + struct list_head ls_root_list; /* root resources */ + struct rw_semaphore ls_root_sem; /* protect root_list */ + + int ls_namelen; + char ls_name[1]; +}; + +#define LSFL_WORK 0 +#define LSFL_RUNNING 1 +#define LSFL_RECOVERY_STOP 2 +#define LSFL_RCOM_READY 3 +#define LSFL_UEVENT_WAIT 4 + +static inline int dlm_locking_stopped(struct dlm_ls *ls) +{ + return !test_bit(LSFL_RUNNING, &ls->ls_flags); +} + +static inline int dlm_recovery_stopped(struct dlm_ls *ls) +{ + return test_bit(LSFL_RECOVERY_STOP, &ls->ls_flags); +} + +static inline int dlm_no_directory(struct dlm_ls *ls) +{ + return (ls->ls_exflags & DLM_LSFL_NODIR) ? 1 : 0; +} + +#endif /* __DLM_INTERNAL_DOT_H__ */ + diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c new file mode 100644 index 000000000000..81efb361f95d --- /dev/null +++ b/fs/dlm/lock.c @@ -0,0 +1,3610 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +/* Central locking logic has four stages: + + dlm_lock() + dlm_unlock() + + request_lock(ls, lkb) + convert_lock(ls, lkb) + unlock_lock(ls, lkb) + cancel_lock(ls, lkb) + + _request_lock(r, lkb) + _convert_lock(r, lkb) + _unlock_lock(r, lkb) + _cancel_lock(r, lkb) + + do_request(r, lkb) + do_convert(r, lkb) + do_unlock(r, lkb) + do_cancel(r, lkb) + + Stage 1 (lock, unlock) is mainly about checking input args and + splitting into one of the four main operations: + + dlm_lock = request_lock + dlm_lock+CONVERT = convert_lock + dlm_unlock = unlock_lock + dlm_unlock+CANCEL = cancel_lock + + Stage 2, xxxx_lock(), just finds and locks the relevant rsb which is + provided to the next stage. + + Stage 3, _xxxx_lock(), determines if the operation is local or remote. + When remote, it calls send_xxxx(), when local it calls do_xxxx(). + + Stage 4, do_xxxx(), is the guts of the operation. It manipulates the + given rsb and lkb and queues callbacks. + + For remote operations, send_xxxx() results in the corresponding do_xxxx() + function being executed on the remote node. The connecting send/receive + calls on local (L) and remote (R) nodes: + + L: send_xxxx() -> R: receive_xxxx() + R: do_xxxx() + L: receive_xxxx_reply() <- R: send_xxxx_reply() +*/ + +#include "dlm_internal.h" +#include "memory.h" +#include "lowcomms.h" +#include "requestqueue.h" +#include "util.h" +#include "dir.h" +#include "member.h" +#include "lockspace.h" +#include "ast.h" +#include "lock.h" +#include "rcom.h" +#include "recover.h" +#include "lvb_table.h" +#include "config.h" + +static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb); +static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb); +static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb); +static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb); +static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb); +static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode); +static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb); +static int send_remove(struct dlm_rsb *r); +static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb); +static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, + struct dlm_message *ms); +static int receive_extralen(struct dlm_message *ms); + +/* + * Lock compatibilty matrix - thanks Steve + * UN = Unlocked state. Not really a state, used as a flag + * PD = Padding. Used to make the matrix a nice power of two in size + * Other states are the same as the VMS DLM. + * Usage: matrix[grmode+1][rqmode+1] (although m[rq+1][gr+1] is the same) + */ + +static const int __dlm_compat_matrix[8][8] = { + /* UN NL CR CW PR PW EX PD */ + {1, 1, 1, 1, 1, 1, 1, 0}, /* UN */ + {1, 1, 1, 1, 1, 1, 1, 0}, /* NL */ + {1, 1, 1, 1, 1, 1, 0, 0}, /* CR */ + {1, 1, 1, 1, 0, 0, 0, 0}, /* CW */ + {1, 1, 1, 0, 1, 0, 0, 0}, /* PR */ + {1, 1, 1, 0, 0, 0, 0, 0}, /* PW */ + {1, 1, 0, 0, 0, 0, 0, 0}, /* EX */ + {0, 0, 0, 0, 0, 0, 0, 0} /* PD */ +}; + +/* + * This defines the direction of transfer of LVB data. + * Granted mode is the row; requested mode is the column. + * Usage: matrix[grmode+1][rqmode+1] + * 1 = LVB is returned to the caller + * 0 = LVB is written to the resource + * -1 = nothing happens to the LVB + */ + +const int dlm_lvb_operations[8][8] = { + /* UN NL CR CW PR PW EX PD*/ + { -1, 1, 1, 1, 1, 1, 1, -1 }, /* UN */ + { -1, 1, 1, 1, 1, 1, 1, 0 }, /* NL */ + { -1, -1, 1, 1, 1, 1, 1, 0 }, /* CR */ + { -1, -1, -1, 1, 1, 1, 1, 0 }, /* CW */ + { -1, -1, -1, -1, 1, 1, 1, 0 }, /* PR */ + { -1, 0, 0, 0, 0, 0, 1, 0 }, /* PW */ + { -1, 0, 0, 0, 0, 0, 0, 0 }, /* EX */ + { -1, 0, 0, 0, 0, 0, 0, 0 } /* PD */ +}; +EXPORT_SYMBOL_GPL(dlm_lvb_operations); + +#define modes_compat(gr, rq) \ + __dlm_compat_matrix[(gr)->lkb_grmode + 1][(rq)->lkb_rqmode + 1] + +int dlm_modes_compat(int mode1, int mode2) +{ + return __dlm_compat_matrix[mode1 + 1][mode2 + 1]; +} + +/* + * Compatibility matrix for conversions with QUECVT set. + * Granted mode is the row; requested mode is the column. + * Usage: matrix[grmode+1][rqmode+1] + */ + +static const int __quecvt_compat_matrix[8][8] = { + /* UN NL CR CW PR PW EX PD */ + {0, 0, 0, 0, 0, 0, 0, 0}, /* UN */ + {0, 0, 1, 1, 1, 1, 1, 0}, /* NL */ + {0, 0, 0, 1, 1, 1, 1, 0}, /* CR */ + {0, 0, 0, 0, 1, 1, 1, 0}, /* CW */ + {0, 0, 0, 1, 0, 1, 1, 0}, /* PR */ + {0, 0, 0, 0, 0, 0, 1, 0}, /* PW */ + {0, 0, 0, 0, 0, 0, 0, 0}, /* EX */ + {0, 0, 0, 0, 0, 0, 0, 0} /* PD */ +}; + +static void dlm_print_lkb(struct dlm_lkb *lkb) +{ + printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x\n" + " status %d rqmode %d grmode %d wait_type %d ast_type %d\n", + lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags, + lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode, + lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_ast_type); +} + +void dlm_print_rsb(struct dlm_rsb *r) +{ + printk(KERN_ERR "rsb: nodeid %d flags %lx first %x rlc %d name %s\n", + r->res_nodeid, r->res_flags, r->res_first_lkid, + r->res_recover_locks_count, r->res_name); +} + +/* Threads cannot use the lockspace while it's being recovered */ + +static inline void lock_recovery(struct dlm_ls *ls) +{ + down_read(&ls->ls_in_recovery); +} + +static inline void unlock_recovery(struct dlm_ls *ls) +{ + up_read(&ls->ls_in_recovery); +} + +static inline int lock_recovery_try(struct dlm_ls *ls) +{ + return down_read_trylock(&ls->ls_in_recovery); +} + +static inline int can_be_queued(struct dlm_lkb *lkb) +{ + return !(lkb->lkb_exflags & DLM_LKF_NOQUEUE); +} + +static inline int force_blocking_asts(struct dlm_lkb *lkb) +{ + return (lkb->lkb_exflags & DLM_LKF_NOQUEUEBAST); +} + +static inline int is_demoted(struct dlm_lkb *lkb) +{ + return (lkb->lkb_sbflags & DLM_SBF_DEMOTED); +} + +static inline int is_remote(struct dlm_rsb *r) +{ + DLM_ASSERT(r->res_nodeid >= 0, dlm_print_rsb(r);); + return !!r->res_nodeid; +} + +static inline int is_process_copy(struct dlm_lkb *lkb) +{ + return (lkb->lkb_nodeid && !(lkb->lkb_flags & DLM_IFL_MSTCPY)); +} + +static inline int is_master_copy(struct dlm_lkb *lkb) +{ + if (lkb->lkb_flags & DLM_IFL_MSTCPY) + DLM_ASSERT(lkb->lkb_nodeid, dlm_print_lkb(lkb);); + return (lkb->lkb_flags & DLM_IFL_MSTCPY) ? TRUE : FALSE; +} + +static inline int middle_conversion(struct dlm_lkb *lkb) +{ + if ((lkb->lkb_grmode==DLM_LOCK_PR && lkb->lkb_rqmode==DLM_LOCK_CW) || + (lkb->lkb_rqmode==DLM_LOCK_PR && lkb->lkb_grmode==DLM_LOCK_CW)) + return TRUE; + return FALSE; +} + +static inline int down_conversion(struct dlm_lkb *lkb) +{ + return (!middle_conversion(lkb) && lkb->lkb_rqmode < lkb->lkb_grmode); +} + +static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) +{ + if (is_master_copy(lkb)) + return; + + DLM_ASSERT(lkb->lkb_lksb, dlm_print_lkb(lkb);); + + lkb->lkb_lksb->sb_status = rv; + lkb->lkb_lksb->sb_flags = lkb->lkb_sbflags; + + dlm_add_ast(lkb, AST_COMP); +} + +static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode) +{ + if (is_master_copy(lkb)) + send_bast(r, lkb, rqmode); + else { + lkb->lkb_bastmode = rqmode; + dlm_add_ast(lkb, AST_BAST); + } +} + +/* + * Basic operations on rsb's and lkb's + */ + +static struct dlm_rsb *create_rsb(struct dlm_ls *ls, char *name, int len) +{ + struct dlm_rsb *r; + + r = allocate_rsb(ls, len); + if (!r) + return NULL; + + r->res_ls = ls; + r->res_length = len; + memcpy(r->res_name, name, len); + init_MUTEX(&r->res_sem); + + INIT_LIST_HEAD(&r->res_lookup); + INIT_LIST_HEAD(&r->res_grantqueue); + INIT_LIST_HEAD(&r->res_convertqueue); + INIT_LIST_HEAD(&r->res_waitqueue); + INIT_LIST_HEAD(&r->res_root_list); + INIT_LIST_HEAD(&r->res_recover_list); + + return r; +} + +static int search_rsb_list(struct list_head *head, char *name, int len, + unsigned int flags, struct dlm_rsb **r_ret) +{ + struct dlm_rsb *r; + int error = 0; + + list_for_each_entry(r, head, res_hashchain) { + if (len == r->res_length && !memcmp(name, r->res_name, len)) + goto found; + } + return -ENOENT; + + found: + if (r->res_nodeid && (flags & R_MASTER)) + error = -ENOTBLK; + *r_ret = r; + return error; +} + +static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b, + unsigned int flags, struct dlm_rsb **r_ret) +{ + struct dlm_rsb *r; + int error; + + error = search_rsb_list(&ls->ls_rsbtbl[b].list, name, len, flags, &r); + if (!error) { + kref_get(&r->res_ref); + goto out; + } + error = search_rsb_list(&ls->ls_rsbtbl[b].toss, name, len, flags, &r); + if (error) + goto out; + + list_move(&r->res_hashchain, &ls->ls_rsbtbl[b].list); + + if (dlm_no_directory(ls)) + goto out; + + if (r->res_nodeid == -1) { + rsb_clear_flag(r, RSB_MASTER_UNCERTAIN); + r->res_first_lkid = 0; + } else if (r->res_nodeid > 0) { + rsb_set_flag(r, RSB_MASTER_UNCERTAIN); + r->res_first_lkid = 0; + } else { + DLM_ASSERT(r->res_nodeid == 0, dlm_print_rsb(r);); + DLM_ASSERT(!rsb_flag(r, RSB_MASTER_UNCERTAIN),); + } + out: + *r_ret = r; + return error; +} + +static int search_rsb(struct dlm_ls *ls, char *name, int len, int b, + unsigned int flags, struct dlm_rsb **r_ret) +{ + int error; + write_lock(&ls->ls_rsbtbl[b].lock); + error = _search_rsb(ls, name, len, b, flags, r_ret); + write_unlock(&ls->ls_rsbtbl[b].lock); + return error; +} + +/* + * Find rsb in rsbtbl and potentially create/add one + * + * Delaying the release of rsb's has a similar benefit to applications keeping + * NL locks on an rsb, but without the guarantee that the cached master value + * will still be valid when the rsb is reused. Apps aren't always smart enough + * to keep NL locks on an rsb that they may lock again shortly; this can lead + * to excessive master lookups and removals if we don't delay the release. + * + * Searching for an rsb means looking through both the normal list and toss + * list. When found on the toss list the rsb is moved to the normal list with + * ref count of 1; when found on normal list the ref count is incremented. + */ + +static int find_rsb(struct dlm_ls *ls, char *name, int namelen, + unsigned int flags, struct dlm_rsb **r_ret) +{ + struct dlm_rsb *r, *tmp; + uint32_t hash, bucket; + int error = 0; + + if (dlm_no_directory(ls)) + flags |= R_CREATE; + + hash = jhash(name, namelen, 0); + bucket = hash & (ls->ls_rsbtbl_size - 1); + + error = search_rsb(ls, name, namelen, bucket, flags, &r); + if (!error) + goto out; + + if (error == -ENOENT && !(flags & R_CREATE)) + goto out; + + /* the rsb was found but wasn't a master copy */ + if (error == -ENOTBLK) + goto out; + + error = -ENOMEM; + r = create_rsb(ls, name, namelen); + if (!r) + goto out; + + r->res_hash = hash; + r->res_bucket = bucket; + r->res_nodeid = -1; + kref_init(&r->res_ref); + + /* With no directory, the master can be set immediately */ + if (dlm_no_directory(ls)) { + int nodeid = dlm_dir_nodeid(r); + if (nodeid == dlm_our_nodeid()) + nodeid = 0; + r->res_nodeid = nodeid; + } + + write_lock(&ls->ls_rsbtbl[bucket].lock); + error = _search_rsb(ls, name, namelen, bucket, 0, &tmp); + if (!error) { + write_unlock(&ls->ls_rsbtbl[bucket].lock); + free_rsb(r); + r = tmp; + goto out; + } + list_add(&r->res_hashchain, &ls->ls_rsbtbl[bucket].list); + write_unlock(&ls->ls_rsbtbl[bucket].lock); + error = 0; + out: + *r_ret = r; + return error; +} + +int dlm_find_rsb(struct dlm_ls *ls, char *name, int namelen, + unsigned int flags, struct dlm_rsb **r_ret) +{ + return find_rsb(ls, name, namelen, flags, r_ret); +} + +/* This is only called to add a reference when the code already holds + a valid reference to the rsb, so there's no need for locking. */ + +static inline void hold_rsb(struct dlm_rsb *r) +{ + kref_get(&r->res_ref); +} + +void dlm_hold_rsb(struct dlm_rsb *r) +{ + hold_rsb(r); +} + +static void toss_rsb(struct kref *kref) +{ + struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref); + struct dlm_ls *ls = r->res_ls; + + DLM_ASSERT(list_empty(&r->res_root_list), dlm_print_rsb(r);); + kref_init(&r->res_ref); + list_move(&r->res_hashchain, &ls->ls_rsbtbl[r->res_bucket].toss); + r->res_toss_time = jiffies; + if (r->res_lvbptr) { + free_lvb(r->res_lvbptr); + r->res_lvbptr = NULL; + } +} + +/* When all references to the rsb are gone it's transfered to + the tossed list for later disposal. */ + +static void put_rsb(struct dlm_rsb *r) +{ + struct dlm_ls *ls = r->res_ls; + uint32_t bucket = r->res_bucket; + + write_lock(&ls->ls_rsbtbl[bucket].lock); + kref_put(&r->res_ref, toss_rsb); + write_unlock(&ls->ls_rsbtbl[bucket].lock); +} + +void dlm_put_rsb(struct dlm_rsb *r) +{ + put_rsb(r); +} + +/* See comment for unhold_lkb */ + +static void unhold_rsb(struct dlm_rsb *r) +{ + int rv; + rv = kref_put(&r->res_ref, toss_rsb); + DLM_ASSERT(!rv, dlm_print_rsb(r);); +} + +static void kill_rsb(struct kref *kref) +{ + struct dlm_rsb *r = container_of(kref, struct dlm_rsb, res_ref); + + /* All work is done after the return from kref_put() so we + can release the write_lock before the remove and free. */ + + DLM_ASSERT(list_empty(&r->res_lookup),); + DLM_ASSERT(list_empty(&r->res_grantqueue),); + DLM_ASSERT(list_empty(&r->res_convertqueue),); + DLM_ASSERT(list_empty(&r->res_waitqueue),); + DLM_ASSERT(list_empty(&r->res_root_list),); + DLM_ASSERT(list_empty(&r->res_recover_list),); +} + +/* Attaching/detaching lkb's from rsb's is for rsb reference counting. + The rsb must exist as long as any lkb's for it do. */ + +static void attach_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + hold_rsb(r); + lkb->lkb_resource = r; +} + +static void detach_lkb(struct dlm_lkb *lkb) +{ + if (lkb->lkb_resource) { + put_rsb(lkb->lkb_resource); + lkb->lkb_resource = NULL; + } +} + +static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret) +{ + struct dlm_lkb *lkb, *tmp; + uint32_t lkid = 0; + uint16_t bucket; + + lkb = allocate_lkb(ls); + if (!lkb) + return -ENOMEM; + + lkb->lkb_nodeid = -1; + lkb->lkb_grmode = DLM_LOCK_IV; + kref_init(&lkb->lkb_ref); + + get_random_bytes(&bucket, sizeof(bucket)); + bucket &= (ls->ls_lkbtbl_size - 1); + + write_lock(&ls->ls_lkbtbl[bucket].lock); + + /* counter can roll over so we must verify lkid is not in use */ + + while (lkid == 0) { + lkid = bucket | (ls->ls_lkbtbl[bucket].counter++ << 16); + + list_for_each_entry(tmp, &ls->ls_lkbtbl[bucket].list, + lkb_idtbl_list) { + if (tmp->lkb_id != lkid) + continue; + lkid = 0; + break; + } + } + + lkb->lkb_id = lkid; + list_add(&lkb->lkb_idtbl_list, &ls->ls_lkbtbl[bucket].list); + write_unlock(&ls->ls_lkbtbl[bucket].lock); + + *lkb_ret = lkb; + return 0; +} + +static struct dlm_lkb *__find_lkb(struct dlm_ls *ls, uint32_t lkid) +{ + uint16_t bucket = lkid & 0xFFFF; + struct dlm_lkb *lkb; + + list_for_each_entry(lkb, &ls->ls_lkbtbl[bucket].list, lkb_idtbl_list) { + if (lkb->lkb_id == lkid) + return lkb; + } + return NULL; +} + +static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret) +{ + struct dlm_lkb *lkb; + uint16_t bucket = lkid & 0xFFFF; + + if (bucket >= ls->ls_lkbtbl_size) + return -EBADSLT; + + read_lock(&ls->ls_lkbtbl[bucket].lock); + lkb = __find_lkb(ls, lkid); + if (lkb) + kref_get(&lkb->lkb_ref); + read_unlock(&ls->ls_lkbtbl[bucket].lock); + + *lkb_ret = lkb; + return lkb ? 0 : -ENOENT; +} + +static void kill_lkb(struct kref *kref) +{ + struct dlm_lkb *lkb = container_of(kref, struct dlm_lkb, lkb_ref); + + /* All work is done after the return from kref_put() so we + can release the write_lock before the detach_lkb */ + + DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb);); +} + +static int put_lkb(struct dlm_lkb *lkb) +{ + struct dlm_ls *ls = lkb->lkb_resource->res_ls; + uint16_t bucket = lkb->lkb_id & 0xFFFF; + + write_lock(&ls->ls_lkbtbl[bucket].lock); + if (kref_put(&lkb->lkb_ref, kill_lkb)) { + list_del(&lkb->lkb_idtbl_list); + write_unlock(&ls->ls_lkbtbl[bucket].lock); + + detach_lkb(lkb); + + /* for local/process lkbs, lvbptr points to caller's lksb */ + if (lkb->lkb_lvbptr && is_master_copy(lkb)) + free_lvb(lkb->lkb_lvbptr); + if (lkb->lkb_range) + free_range(lkb->lkb_range); + free_lkb(lkb); + return 1; + } else { + write_unlock(&ls->ls_lkbtbl[bucket].lock); + return 0; + } +} + +int dlm_put_lkb(struct dlm_lkb *lkb) +{ + return put_lkb(lkb); +} + +/* This is only called to add a reference when the code already holds + a valid reference to the lkb, so there's no need for locking. */ + +static inline void hold_lkb(struct dlm_lkb *lkb) +{ + kref_get(&lkb->lkb_ref); +} + +/* This is called when we need to remove a reference and are certain + it's not the last ref. e.g. del_lkb is always called between a + find_lkb/put_lkb and is always the inverse of a previous add_lkb. + put_lkb would work fine, but would involve unnecessary locking */ + +static inline void unhold_lkb(struct dlm_lkb *lkb) +{ + int rv; + rv = kref_put(&lkb->lkb_ref, kill_lkb); + DLM_ASSERT(!rv, dlm_print_lkb(lkb);); +} + +static void lkb_add_ordered(struct list_head *new, struct list_head *head, + int mode) +{ + struct dlm_lkb *lkb = NULL; + + list_for_each_entry(lkb, head, lkb_statequeue) + if (lkb->lkb_rqmode < mode) + break; + + if (!lkb) + list_add_tail(new, head); + else + __list_add(new, lkb->lkb_statequeue.prev, &lkb->lkb_statequeue); +} + +/* add/remove lkb to rsb's grant/convert/wait queue */ + +static void add_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int status) +{ + kref_get(&lkb->lkb_ref); + + DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb);); + + lkb->lkb_status = status; + + switch (status) { + case DLM_LKSTS_WAITING: + if (lkb->lkb_exflags & DLM_LKF_HEADQUE) + list_add(&lkb->lkb_statequeue, &r->res_waitqueue); + else + list_add_tail(&lkb->lkb_statequeue, &r->res_waitqueue); + break; + case DLM_LKSTS_GRANTED: + /* convention says granted locks kept in order of grmode */ + lkb_add_ordered(&lkb->lkb_statequeue, &r->res_grantqueue, + lkb->lkb_grmode); + break; + case DLM_LKSTS_CONVERT: + if (lkb->lkb_exflags & DLM_LKF_HEADQUE) + list_add(&lkb->lkb_statequeue, &r->res_convertqueue); + else + list_add_tail(&lkb->lkb_statequeue, + &r->res_convertqueue); + break; + default: + DLM_ASSERT(0, dlm_print_lkb(lkb); printk("sts=%d\n", status);); + } +} + +static void del_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + lkb->lkb_status = 0; + list_del(&lkb->lkb_statequeue); + unhold_lkb(lkb); +} + +static void move_lkb(struct dlm_rsb *r, struct dlm_lkb *lkb, int sts) +{ + hold_lkb(lkb); + del_lkb(r, lkb); + add_lkb(r, lkb, sts); + unhold_lkb(lkb); +} + +/* add/remove lkb from global waiters list of lkb's waiting for + a reply from a remote node */ + +static void add_to_waiters(struct dlm_lkb *lkb, int mstype) +{ + struct dlm_ls *ls = lkb->lkb_resource->res_ls; + + down(&ls->ls_waiters_sem); + if (lkb->lkb_wait_type) { + log_print("add_to_waiters error %d", lkb->lkb_wait_type); + goto out; + } + lkb->lkb_wait_type = mstype; + kref_get(&lkb->lkb_ref); + list_add(&lkb->lkb_wait_reply, &ls->ls_waiters); + out: + up(&ls->ls_waiters_sem); +} + +static int _remove_from_waiters(struct dlm_lkb *lkb) +{ + int error = 0; + + if (!lkb->lkb_wait_type) { + log_print("remove_from_waiters error"); + error = -EINVAL; + goto out; + } + lkb->lkb_wait_type = 0; + list_del(&lkb->lkb_wait_reply); + unhold_lkb(lkb); + out: + return error; +} + +static int remove_from_waiters(struct dlm_lkb *lkb) +{ + struct dlm_ls *ls = lkb->lkb_resource->res_ls; + int error; + + down(&ls->ls_waiters_sem); + error = _remove_from_waiters(lkb); + up(&ls->ls_waiters_sem); + return error; +} + +static void dir_remove(struct dlm_rsb *r) +{ + int to_nodeid; + + if (dlm_no_directory(r->res_ls)) + return; + + to_nodeid = dlm_dir_nodeid(r); + if (to_nodeid != dlm_our_nodeid()) + send_remove(r); + else + dlm_dir_remove_entry(r->res_ls, to_nodeid, + r->res_name, r->res_length); +} + +/* FIXME: shouldn't this be able to exit as soon as one non-due rsb is + found since they are in order of newest to oldest? */ + +static int shrink_bucket(struct dlm_ls *ls, int b) +{ + struct dlm_rsb *r; + int count = 0, found; + + for (;;) { + found = FALSE; + write_lock(&ls->ls_rsbtbl[b].lock); + list_for_each_entry_reverse(r, &ls->ls_rsbtbl[b].toss, + res_hashchain) { + if (!time_after_eq(jiffies, r->res_toss_time + + dlm_config.toss_secs * HZ)) + continue; + found = TRUE; + break; + } + + if (!found) { + write_unlock(&ls->ls_rsbtbl[b].lock); + break; + } + + if (kref_put(&r->res_ref, kill_rsb)) { + list_del(&r->res_hashchain); + write_unlock(&ls->ls_rsbtbl[b].lock); + + if (is_master(r)) + dir_remove(r); + free_rsb(r); + count++; + } else { + write_unlock(&ls->ls_rsbtbl[b].lock); + log_error(ls, "tossed rsb in use %s", r->res_name); + } + } + + return count; +} + +void dlm_scan_rsbs(struct dlm_ls *ls) +{ + int i; + + if (dlm_locking_stopped(ls)) + return; + + for (i = 0; i < ls->ls_rsbtbl_size; i++) { + shrink_bucket(ls, i); + cond_resched(); + } +} + +/* lkb is master or local copy */ + +static void set_lvb_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int b, len = r->res_ls->ls_lvblen; + + /* b=1 lvb returned to caller + b=0 lvb written to rsb or invalidated + b=-1 do nothing */ + + b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1]; + + if (b == 1) { + if (!lkb->lkb_lvbptr) + return; + + if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + return; + + if (!r->res_lvbptr) + return; + + memcpy(lkb->lkb_lvbptr, r->res_lvbptr, len); + lkb->lkb_lvbseq = r->res_lvbseq; + + } else if (b == 0) { + if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) { + rsb_set_flag(r, RSB_VALNOTVALID); + return; + } + + if (!lkb->lkb_lvbptr) + return; + + if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + return; + + if (!r->res_lvbptr) + r->res_lvbptr = allocate_lvb(r->res_ls); + + if (!r->res_lvbptr) + return; + + memcpy(r->res_lvbptr, lkb->lkb_lvbptr, len); + r->res_lvbseq++; + lkb->lkb_lvbseq = r->res_lvbseq; + rsb_clear_flag(r, RSB_VALNOTVALID); + } + + if (rsb_flag(r, RSB_VALNOTVALID)) + lkb->lkb_sbflags |= DLM_SBF_VALNOTVALID; +} + +static void set_lvb_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + if (lkb->lkb_grmode < DLM_LOCK_PW) + return; + + if (lkb->lkb_exflags & DLM_LKF_IVVALBLK) { + rsb_set_flag(r, RSB_VALNOTVALID); + return; + } + + if (!lkb->lkb_lvbptr) + return; + + if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + return; + + if (!r->res_lvbptr) + r->res_lvbptr = allocate_lvb(r->res_ls); + + if (!r->res_lvbptr) + return; + + memcpy(r->res_lvbptr, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); + r->res_lvbseq++; + rsb_clear_flag(r, RSB_VALNOTVALID); +} + +/* lkb is process copy (pc) */ + +static void set_lvb_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + int b; + + if (!lkb->lkb_lvbptr) + return; + + if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + return; + + b = dlm_lvb_operations[lkb->lkb_grmode + 1][lkb->lkb_rqmode + 1]; + if (b == 1) { + int len = receive_extralen(ms); + memcpy(lkb->lkb_lvbptr, ms->m_extra, len); + lkb->lkb_lvbseq = ms->m_lvbseq; + } +} + +/* Manipulate lkb's on rsb's convert/granted/waiting queues + remove_lock -- used for unlock, removes lkb from granted + revert_lock -- used for cancel, moves lkb from convert to granted + grant_lock -- used for request and convert, adds lkb to granted or + moves lkb from convert or waiting to granted + + Each of these is used for master or local copy lkb's. There is + also a _pc() variation used to make the corresponding change on + a process copy (pc) lkb. */ + +static void _remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + del_lkb(r, lkb); + lkb->lkb_grmode = DLM_LOCK_IV; + /* this unhold undoes the original ref from create_lkb() + so this leads to the lkb being freed */ + unhold_lkb(lkb); +} + +static void remove_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + set_lvb_unlock(r, lkb); + _remove_lock(r, lkb); +} + +static void remove_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + _remove_lock(r, lkb); +} + +static void revert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + lkb->lkb_rqmode = DLM_LOCK_IV; + + switch (lkb->lkb_status) { + case DLM_LKSTS_CONVERT: + move_lkb(r, lkb, DLM_LKSTS_GRANTED); + break; + case DLM_LKSTS_WAITING: + del_lkb(r, lkb); + lkb->lkb_grmode = DLM_LOCK_IV; + /* this unhold undoes the original ref from create_lkb() + so this leads to the lkb being freed */ + unhold_lkb(lkb); + break; + default: + log_print("invalid status for revert %d", lkb->lkb_status); + } +} + +static void revert_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + revert_lock(r, lkb); +} + +static void _grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + if (lkb->lkb_grmode != lkb->lkb_rqmode) { + lkb->lkb_grmode = lkb->lkb_rqmode; + if (lkb->lkb_status) + move_lkb(r, lkb, DLM_LKSTS_GRANTED); + else + add_lkb(r, lkb, DLM_LKSTS_GRANTED); + } + + lkb->lkb_rqmode = DLM_LOCK_IV; + + if (lkb->lkb_range) { + lkb->lkb_range[GR_RANGE_START] = lkb->lkb_range[RQ_RANGE_START]; + lkb->lkb_range[GR_RANGE_END] = lkb->lkb_range[RQ_RANGE_END]; + } +} + +static void grant_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + set_lvb_lock(r, lkb); + _grant_lock(r, lkb); + lkb->lkb_highbast = 0; +} + +static void grant_lock_pc(struct dlm_rsb *r, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + set_lvb_lock_pc(r, lkb, ms); + _grant_lock(r, lkb); +} + +/* called by grant_pending_locks() which means an async grant message must + be sent to the requesting node in addition to granting the lock if the + lkb belongs to a remote node. */ + +static void grant_lock_pending(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + grant_lock(r, lkb); + if (is_master_copy(lkb)) + send_grant(r, lkb); + else + queue_cast(r, lkb, 0); +} + +static inline int first_in_list(struct dlm_lkb *lkb, struct list_head *head) +{ + struct dlm_lkb *first = list_entry(head->next, struct dlm_lkb, + lkb_statequeue); + if (lkb->lkb_id == first->lkb_id) + return TRUE; + + return FALSE; +} + +/* Return 1 if the locks' ranges overlap. If the lkb has no range then it is + assumed to cover 0-ffffffff.ffffffff */ + +static inline int ranges_overlap(struct dlm_lkb *lkb1, struct dlm_lkb *lkb2) +{ + if (!lkb1->lkb_range || !lkb2->lkb_range) + return TRUE; + + if (lkb1->lkb_range[RQ_RANGE_END] < lkb2->lkb_range[GR_RANGE_START] || + lkb1->lkb_range[RQ_RANGE_START] > lkb2->lkb_range[GR_RANGE_END]) + return FALSE; + + return TRUE; +} + +/* Check if the given lkb conflicts with another lkb on the queue. */ + +static int queue_conflict(struct list_head *head, struct dlm_lkb *lkb) +{ + struct dlm_lkb *this; + + list_for_each_entry(this, head, lkb_statequeue) { + if (this == lkb) + continue; + if (ranges_overlap(lkb, this) && !modes_compat(this, lkb)) + return TRUE; + } + return FALSE; +} + +/* + * "A conversion deadlock arises with a pair of lock requests in the converting + * queue for one resource. The granted mode of each lock blocks the requested + * mode of the other lock." + * + * Part 2: if the granted mode of lkb is preventing the first lkb in the + * convert queue from being granted, then demote lkb (set grmode to NL). + * This second form requires that we check for conv-deadlk even when + * now == 0 in _can_be_granted(). + * + * Example: + * Granted Queue: empty + * Convert Queue: NL->EX (first lock) + * PR->EX (second lock) + * + * The first lock can't be granted because of the granted mode of the second + * lock and the second lock can't be granted because it's not first in the + * list. We demote the granted mode of the second lock (the lkb passed to this + * function). + * + * After the resolution, the "grant pending" function needs to go back and try + * to grant locks on the convert queue again since the first lock can now be + * granted. + */ + +static int conversion_deadlock_detect(struct dlm_rsb *rsb, struct dlm_lkb *lkb) +{ + struct dlm_lkb *this, *first = NULL, *self = NULL; + + list_for_each_entry(this, &rsb->res_convertqueue, lkb_statequeue) { + if (!first) + first = this; + if (this == lkb) { + self = lkb; + continue; + } + + if (!ranges_overlap(lkb, this)) + continue; + + if (!modes_compat(this, lkb) && !modes_compat(lkb, this)) + return TRUE; + } + + /* if lkb is on the convert queue and is preventing the first + from being granted, then there's deadlock and we demote lkb. + multiple converting locks may need to do this before the first + converting lock can be granted. */ + + if (self && self != first) { + if (!modes_compat(lkb, first) && + !queue_conflict(&rsb->res_grantqueue, first)) + return TRUE; + } + + return FALSE; +} + +/* + * Return 1 if the lock can be granted, 0 otherwise. + * Also detect and resolve conversion deadlocks. + * + * lkb is the lock to be granted + * + * now is 1 if the function is being called in the context of the + * immediate request, it is 0 if called later, after the lock has been + * queued. + * + * References are from chapter 6 of "VAXcluster Principles" by Roy Davis + */ + +static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now) +{ + int8_t conv = (lkb->lkb_grmode != DLM_LOCK_IV); + + /* + * 6-10: Version 5.4 introduced an option to address the phenomenon of + * a new request for a NL mode lock being blocked. + * + * 6-11: If the optional EXPEDITE flag is used with the new NL mode + * request, then it would be granted. In essence, the use of this flag + * tells the Lock Manager to expedite theis request by not considering + * what may be in the CONVERTING or WAITING queues... As of this + * writing, the EXPEDITE flag can be used only with new requests for NL + * mode locks. This flag is not valid for conversion requests. + * + * A shortcut. Earlier checks return an error if EXPEDITE is used in a + * conversion or used with a non-NL requested mode. We also know an + * EXPEDITE request is always granted immediately, so now must always + * be 1. The full condition to grant an expedite request: (now && + * !conv && lkb->rqmode == DLM_LOCK_NL && (flags & EXPEDITE)) can + * therefore be shortened to just checking the flag. + */ + + if (lkb->lkb_exflags & DLM_LKF_EXPEDITE) + return TRUE; + + /* + * A shortcut. Without this, !queue_conflict(grantqueue, lkb) would be + * added to the remaining conditions. + */ + + if (queue_conflict(&r->res_grantqueue, lkb)) + goto out; + + /* + * 6-3: By default, a conversion request is immediately granted if the + * requested mode is compatible with the modes of all other granted + * locks + */ + + if (queue_conflict(&r->res_convertqueue, lkb)) + goto out; + + /* + * 6-5: But the default algorithm for deciding whether to grant or + * queue conversion requests does not by itself guarantee that such + * requests are serviced on a "first come first serve" basis. This, in + * turn, can lead to a phenomenon known as "indefinate postponement". + * + * 6-7: This issue is dealt with by using the optional QUECVT flag with + * the system service employed to request a lock conversion. This flag + * forces certain conversion requests to be queued, even if they are + * compatible with the granted modes of other locks on the same + * resource. Thus, the use of this flag results in conversion requests + * being ordered on a "first come first servce" basis. + * + * DCT: This condition is all about new conversions being able to occur + * "in place" while the lock remains on the granted queue (assuming + * nothing else conflicts.) IOW if QUECVT isn't set, a conversion + * doesn't _have_ to go onto the convert queue where it's processed in + * order. The "now" variable is necessary to distinguish converts + * being received and processed for the first time now, because once a + * convert is moved to the conversion queue the condition below applies + * requiring fifo granting. + */ + + if (now && conv && !(lkb->lkb_exflags & DLM_LKF_QUECVT)) + return TRUE; + + /* + * When using range locks the NOORDER flag is set to avoid the standard + * vms rules on grant order. + */ + + if (lkb->lkb_exflags & DLM_LKF_NOORDER) + return TRUE; + + /* + * 6-3: Once in that queue [CONVERTING], a conversion request cannot be + * granted until all other conversion requests ahead of it are granted + * and/or canceled. + */ + + if (!now && conv && first_in_list(lkb, &r->res_convertqueue)) + return TRUE; + + /* + * 6-4: By default, a new request is immediately granted only if all + * three of the following conditions are satisfied when the request is + * issued: + * - The queue of ungranted conversion requests for the resource is + * empty. + * - The queue of ungranted new requests for the resource is empty. + * - The mode of the new request is compatible with the most + * restrictive mode of all granted locks on the resource. + */ + + if (now && !conv && list_empty(&r->res_convertqueue) && + list_empty(&r->res_waitqueue)) + return TRUE; + + /* + * 6-4: Once a lock request is in the queue of ungranted new requests, + * it cannot be granted until the queue of ungranted conversion + * requests is empty, all ungranted new requests ahead of it are + * granted and/or canceled, and it is compatible with the granted mode + * of the most restrictive lock granted on the resource. + */ + + if (!now && !conv && list_empty(&r->res_convertqueue) && + first_in_list(lkb, &r->res_waitqueue)) + return TRUE; + + out: + /* + * The following, enabled by CONVDEADLK, departs from VMS. + */ + + if (conv && (lkb->lkb_exflags & DLM_LKF_CONVDEADLK) && + conversion_deadlock_detect(r, lkb)) { + lkb->lkb_grmode = DLM_LOCK_NL; + lkb->lkb_sbflags |= DLM_SBF_DEMOTED; + } + + return FALSE; +} + +/* + * The ALTPR and ALTCW flags aren't traditional lock manager flags, but are a + * simple way to provide a big optimization to applications that can use them. + */ + +static int can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now) +{ + uint32_t flags = lkb->lkb_exflags; + int rv; + int8_t alt = 0, rqmode = lkb->lkb_rqmode; + + rv = _can_be_granted(r, lkb, now); + if (rv) + goto out; + + if (lkb->lkb_sbflags & DLM_SBF_DEMOTED) + goto out; + + if (rqmode != DLM_LOCK_PR && flags & DLM_LKF_ALTPR) + alt = DLM_LOCK_PR; + else if (rqmode != DLM_LOCK_CW && flags & DLM_LKF_ALTCW) + alt = DLM_LOCK_CW; + + if (alt) { + lkb->lkb_rqmode = alt; + rv = _can_be_granted(r, lkb, now); + if (rv) + lkb->lkb_sbflags |= DLM_SBF_ALTMODE; + else + lkb->lkb_rqmode = rqmode; + } + out: + return rv; +} + +static int grant_pending_convert(struct dlm_rsb *r, int high) +{ + struct dlm_lkb *lkb, *s; + int hi, demoted, quit, grant_restart, demote_restart; + + quit = 0; + restart: + grant_restart = 0; + demote_restart = 0; + hi = DLM_LOCK_IV; + + list_for_each_entry_safe(lkb, s, &r->res_convertqueue, lkb_statequeue) { + demoted = is_demoted(lkb); + if (can_be_granted(r, lkb, FALSE)) { + grant_lock_pending(r, lkb); + grant_restart = 1; + } else { + hi = max_t(int, lkb->lkb_rqmode, hi); + if (!demoted && is_demoted(lkb)) + demote_restart = 1; + } + } + + if (grant_restart) + goto restart; + if (demote_restart && !quit) { + quit = 1; + goto restart; + } + + return max_t(int, high, hi); +} + +static int grant_pending_wait(struct dlm_rsb *r, int high) +{ + struct dlm_lkb *lkb, *s; + + list_for_each_entry_safe(lkb, s, &r->res_waitqueue, lkb_statequeue) { + if (can_be_granted(r, lkb, FALSE)) + grant_lock_pending(r, lkb); + else + high = max_t(int, lkb->lkb_rqmode, high); + } + + return high; +} + +static void grant_pending_locks(struct dlm_rsb *r) +{ + struct dlm_lkb *lkb, *s; + int high = DLM_LOCK_IV; + + DLM_ASSERT(is_master(r), dlm_print_rsb(r);); + + high = grant_pending_convert(r, high); + high = grant_pending_wait(r, high); + + if (high == DLM_LOCK_IV) + return; + + /* + * If there are locks left on the wait/convert queue then send blocking + * ASTs to granted locks based on the largest requested mode (high) + * found above. This can generate spurious blocking ASTs for range + * locks. FIXME: highbast < high comparison not valid for PR/CW. + */ + + list_for_each_entry_safe(lkb, s, &r->res_grantqueue, lkb_statequeue) { + if (lkb->lkb_bastaddr && (lkb->lkb_highbast < high) && + !__dlm_compat_matrix[lkb->lkb_grmode+1][high+1]) { + queue_bast(r, lkb, high); + lkb->lkb_highbast = high; + } + } +} + +static void send_bast_queue(struct dlm_rsb *r, struct list_head *head, + struct dlm_lkb *lkb) +{ + struct dlm_lkb *gr; + + list_for_each_entry(gr, head, lkb_statequeue) { + if (gr->lkb_bastaddr && + gr->lkb_highbast < lkb->lkb_rqmode && + ranges_overlap(lkb, gr) && !modes_compat(gr, lkb)) { + queue_bast(r, gr, lkb->lkb_rqmode); + gr->lkb_highbast = lkb->lkb_rqmode; + } + } +} + +static void send_blocking_asts(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + send_bast_queue(r, &r->res_grantqueue, lkb); +} + +static void send_blocking_asts_all(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + send_bast_queue(r, &r->res_grantqueue, lkb); + send_bast_queue(r, &r->res_convertqueue, lkb); +} + +/* set_master(r, lkb) -- set the master nodeid of a resource + + The purpose of this function is to set the nodeid field in the given + lkb using the nodeid field in the given rsb. If the rsb's nodeid is + known, it can just be copied to the lkb and the function will return + 0. If the rsb's nodeid is _not_ known, it needs to be looked up + before it can be copied to the lkb. + + When the rsb nodeid is being looked up remotely, the initial lkb + causing the lookup is kept on the ls_waiters list waiting for the + lookup reply. Other lkb's waiting for the same rsb lookup are kept + on the rsb's res_lookup list until the master is verified. + + Return values: + 0: nodeid is set in rsb/lkb and the caller should go ahead and use it + 1: the rsb master is not available and the lkb has been placed on + a wait queue +*/ + +static int set_master(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + struct dlm_ls *ls = r->res_ls; + int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid(); + + if (rsb_flag(r, RSB_MASTER_UNCERTAIN)) { + rsb_clear_flag(r, RSB_MASTER_UNCERTAIN); + r->res_first_lkid = lkb->lkb_id; + lkb->lkb_nodeid = r->res_nodeid; + return 0; + } + + if (r->res_first_lkid && r->res_first_lkid != lkb->lkb_id) { + list_add_tail(&lkb->lkb_rsb_lookup, &r->res_lookup); + return 1; + } + + if (r->res_nodeid == 0) { + lkb->lkb_nodeid = 0; + return 0; + } + + if (r->res_nodeid > 0) { + lkb->lkb_nodeid = r->res_nodeid; + return 0; + } + + DLM_ASSERT(r->res_nodeid == -1, dlm_print_rsb(r);); + + dir_nodeid = dlm_dir_nodeid(r); + + if (dir_nodeid != our_nodeid) { + r->res_first_lkid = lkb->lkb_id; + send_lookup(r, lkb); + return 1; + } + + for (;;) { + /* It's possible for dlm_scand to remove an old rsb for + this same resource from the toss list, us to create + a new one, look up the master locally, and find it + already exists just before dlm_scand does the + dir_remove() on the previous rsb. */ + + error = dlm_dir_lookup(ls, our_nodeid, r->res_name, + r->res_length, &ret_nodeid); + if (!error) + break; + log_debug(ls, "dir_lookup error %d %s", error, r->res_name); + schedule(); + } + + if (ret_nodeid == our_nodeid) { + r->res_first_lkid = 0; + r->res_nodeid = 0; + lkb->lkb_nodeid = 0; + } else { + r->res_first_lkid = lkb->lkb_id; + r->res_nodeid = ret_nodeid; + lkb->lkb_nodeid = ret_nodeid; + } + return 0; +} + +static void process_lookup_list(struct dlm_rsb *r) +{ + struct dlm_lkb *lkb, *safe; + + list_for_each_entry_safe(lkb, safe, &r->res_lookup, lkb_rsb_lookup) { + list_del(&lkb->lkb_rsb_lookup); + _request_lock(r, lkb); + schedule(); + } +} + +/* confirm_master -- confirm (or deny) an rsb's master nodeid */ + +static void confirm_master(struct dlm_rsb *r, int error) +{ + struct dlm_lkb *lkb; + + if (!r->res_first_lkid) + return; + + switch (error) { + case 0: + case -EINPROGRESS: + r->res_first_lkid = 0; + process_lookup_list(r); + break; + + case -EAGAIN: + /* the remote master didn't queue our NOQUEUE request; + make a waiting lkb the first_lkid */ + + r->res_first_lkid = 0; + + if (!list_empty(&r->res_lookup)) { + lkb = list_entry(r->res_lookup.next, struct dlm_lkb, + lkb_rsb_lookup); + list_del(&lkb->lkb_rsb_lookup); + r->res_first_lkid = lkb->lkb_id; + _request_lock(r, lkb); + } else + r->res_nodeid = -1; + break; + + default: + log_error(r->res_ls, "confirm_master unknown error %d", error); + } +} + +static int set_lock_args(int mode, struct dlm_lksb *lksb, uint32_t flags, + int namelen, uint32_t parent_lkid, void *ast, + void *astarg, void *bast, struct dlm_range *range, + struct dlm_args *args) +{ + int rv = -EINVAL; + + /* check for invalid arg usage */ + + if (mode < 0 || mode > DLM_LOCK_EX) + goto out; + + if (!(flags & DLM_LKF_CONVERT) && (namelen > DLM_RESNAME_MAXLEN)) + goto out; + + if (flags & DLM_LKF_CANCEL) + goto out; + + if (flags & DLM_LKF_QUECVT && !(flags & DLM_LKF_CONVERT)) + goto out; + + if (flags & DLM_LKF_CONVDEADLK && !(flags & DLM_LKF_CONVERT)) + goto out; + + if (flags & DLM_LKF_CONVDEADLK && flags & DLM_LKF_NOQUEUE) + goto out; + + if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_CONVERT) + goto out; + + if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_QUECVT) + goto out; + + if (flags & DLM_LKF_EXPEDITE && flags & DLM_LKF_NOQUEUE) + goto out; + + if (flags & DLM_LKF_EXPEDITE && mode != DLM_LOCK_NL) + goto out; + + if (!ast || !lksb) + goto out; + + if (flags & DLM_LKF_VALBLK && !lksb->sb_lvbptr) + goto out; + + /* parent/child locks not yet supported */ + if (parent_lkid) + goto out; + + if (flags & DLM_LKF_CONVERT && !lksb->sb_lkid) + goto out; + + /* these args will be copied to the lkb in validate_lock_args, + it cannot be done now because when converting locks, fields in + an active lkb cannot be modified before locking the rsb */ + + args->flags = flags; + args->astaddr = ast; + args->astparam = (long) astarg; + args->bastaddr = bast; + args->mode = mode; + args->lksb = lksb; + args->range = range; + rv = 0; + out: + return rv; +} + +static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args) +{ + if (flags & ~(DLM_LKF_CANCEL | DLM_LKF_VALBLK | DLM_LKF_IVVALBLK | + DLM_LKF_FORCEUNLOCK)) + return -EINVAL; + + args->flags = flags; + args->astparam = (long) astarg; + return 0; +} + +static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_args *args) +{ + int rv = -EINVAL; + + if (args->flags & DLM_LKF_CONVERT) { + if (lkb->lkb_flags & DLM_IFL_MSTCPY) + goto out; + + if (args->flags & DLM_LKF_QUECVT && + !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1]) + goto out; + + rv = -EBUSY; + if (lkb->lkb_status != DLM_LKSTS_GRANTED) + goto out; + + if (lkb->lkb_wait_type) + goto out; + } + + lkb->lkb_exflags = args->flags; + lkb->lkb_sbflags = 0; + lkb->lkb_astaddr = args->astaddr; + lkb->lkb_astparam = args->astparam; + lkb->lkb_bastaddr = args->bastaddr; + lkb->lkb_rqmode = args->mode; + lkb->lkb_lksb = args->lksb; + lkb->lkb_lvbptr = args->lksb->sb_lvbptr; + lkb->lkb_ownpid = (int) current->pid; + + rv = 0; + if (!args->range) + goto out; + + if (!lkb->lkb_range) { + rv = -ENOMEM; + lkb->lkb_range = allocate_range(ls); + if (!lkb->lkb_range) + goto out; + /* This is needed for conversions that contain ranges + where the original lock didn't but it's harmless for + new locks too. */ + lkb->lkb_range[GR_RANGE_START] = 0LL; + lkb->lkb_range[GR_RANGE_END] = 0xffffffffffffffffULL; + } + + lkb->lkb_range[RQ_RANGE_START] = args->range->ra_start; + lkb->lkb_range[RQ_RANGE_END] = args->range->ra_end; + lkb->lkb_flags |= DLM_IFL_RANGE; + rv = 0; + out: + return rv; +} + +static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args) +{ + int rv = -EINVAL; + + if (lkb->lkb_flags & DLM_IFL_MSTCPY) + goto out; + + if (args->flags & DLM_LKF_FORCEUNLOCK) + goto out_ok; + + if (args->flags & DLM_LKF_CANCEL && + lkb->lkb_status == DLM_LKSTS_GRANTED) + goto out; + + if (!(args->flags & DLM_LKF_CANCEL) && + lkb->lkb_status != DLM_LKSTS_GRANTED) + goto out; + + rv = -EBUSY; + if (lkb->lkb_wait_type) + goto out; + + out_ok: + lkb->lkb_exflags = args->flags; + lkb->lkb_sbflags = 0; + lkb->lkb_astparam = args->astparam; + + rv = 0; + out: + return rv; +} + +/* + * Four stage 4 varieties: + * do_request(), do_convert(), do_unlock(), do_cancel() + * These are called on the master node for the given lock and + * from the central locking logic. + */ + +static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int error = 0; + + if (can_be_granted(r, lkb, TRUE)) { + grant_lock(r, lkb); + queue_cast(r, lkb, 0); + goto out; + } + + if (can_be_queued(lkb)) { + error = -EINPROGRESS; + add_lkb(r, lkb, DLM_LKSTS_WAITING); + send_blocking_asts(r, lkb); + goto out; + } + + error = -EAGAIN; + if (force_blocking_asts(lkb)) + send_blocking_asts_all(r, lkb); + queue_cast(r, lkb, -EAGAIN); + + out: + return error; +} + +static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int error = 0; + + /* changing an existing lock may allow others to be granted */ + + if (can_be_granted(r, lkb, TRUE)) { + grant_lock(r, lkb); + queue_cast(r, lkb, 0); + grant_pending_locks(r); + goto out; + } + + if (can_be_queued(lkb)) { + if (is_demoted(lkb)) + grant_pending_locks(r); + error = -EINPROGRESS; + del_lkb(r, lkb); + add_lkb(r, lkb, DLM_LKSTS_CONVERT); + send_blocking_asts(r, lkb); + goto out; + } + + error = -EAGAIN; + if (force_blocking_asts(lkb)) + send_blocking_asts_all(r, lkb); + queue_cast(r, lkb, -EAGAIN); + + out: + return error; +} + +static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + remove_lock(r, lkb); + queue_cast(r, lkb, -DLM_EUNLOCK); + grant_pending_locks(r); + return -DLM_EUNLOCK; +} + +static int do_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + revert_lock(r, lkb); + queue_cast(r, lkb, -DLM_ECANCEL); + grant_pending_locks(r); + return -DLM_ECANCEL; +} + +/* + * Four stage 3 varieties: + * _request_lock(), _convert_lock(), _unlock_lock(), _cancel_lock() + */ + +/* add a new lkb to a possibly new rsb, called by requesting process */ + +static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int error; + + /* set_master: sets lkb nodeid from r */ + + error = set_master(r, lkb); + if (error < 0) + goto out; + if (error) { + error = 0; + goto out; + } + + if (is_remote(r)) + /* receive_request() calls do_request() on remote node */ + error = send_request(r, lkb); + else + error = do_request(r, lkb); + out: + return error; +} + +/* change some property of an existing lkb, e.g. mode, range */ + +static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int error; + + if (is_remote(r)) + /* receive_convert() calls do_convert() on remote node */ + error = send_convert(r, lkb); + else + error = do_convert(r, lkb); + + return error; +} + +/* remove an existing lkb from the granted queue */ + +static int _unlock_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int error; + + if (is_remote(r)) + /* receive_unlock() calls do_unlock() on remote node */ + error = send_unlock(r, lkb); + else + error = do_unlock(r, lkb); + + return error; +} + +/* remove an existing lkb from the convert or wait queue */ + +static int _cancel_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int error; + + if (is_remote(r)) + /* receive_cancel() calls do_cancel() on remote node */ + error = send_cancel(r, lkb); + else + error = do_cancel(r, lkb); + + return error; +} + +/* + * Four stage 2 varieties: + * request_lock(), convert_lock(), unlock_lock(), cancel_lock() + */ + +static int request_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, char *name, + int len, struct dlm_args *args) +{ + struct dlm_rsb *r; + int error; + + error = validate_lock_args(ls, lkb, args); + if (error) + goto out; + + error = find_rsb(ls, name, len, R_CREATE, &r); + if (error) + goto out; + + lock_rsb(r); + + attach_lkb(r, lkb); + lkb->lkb_lksb->sb_lkid = lkb->lkb_id; + + error = _request_lock(r, lkb); + + unlock_rsb(r); + put_rsb(r); + + out: + return error; +} + +static int convert_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_args *args) +{ + struct dlm_rsb *r; + int error; + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + error = validate_lock_args(ls, lkb, args); + if (error) + goto out; + + error = _convert_lock(r, lkb); + out: + unlock_rsb(r); + put_rsb(r); + return error; +} + +static int unlock_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_args *args) +{ + struct dlm_rsb *r; + int error; + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + error = validate_unlock_args(lkb, args); + if (error) + goto out; + + error = _unlock_lock(r, lkb); + out: + unlock_rsb(r); + put_rsb(r); + return error; +} + +static int cancel_lock(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_args *args) +{ + struct dlm_rsb *r; + int error; + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + error = validate_unlock_args(lkb, args); + if (error) + goto out; + + error = _cancel_lock(r, lkb); + out: + unlock_rsb(r); + put_rsb(r); + return error; +} + +/* + * Two stage 1 varieties: dlm_lock() and dlm_unlock() + */ + +int dlm_lock(dlm_lockspace_t *lockspace, + int mode, + struct dlm_lksb *lksb, + uint32_t flags, + void *name, + unsigned int namelen, + uint32_t parent_lkid, + void (*ast) (void *astarg), + void *astarg, + void (*bast) (void *astarg, int mode), + struct dlm_range *range) +{ + struct dlm_ls *ls; + struct dlm_lkb *lkb; + struct dlm_args args; + int error, convert = flags & DLM_LKF_CONVERT; + + ls = dlm_find_lockspace_local(lockspace); + if (!ls) + return -EINVAL; + + lock_recovery(ls); + + if (convert) + error = find_lkb(ls, lksb->sb_lkid, &lkb); + else + error = create_lkb(ls, &lkb); + + if (error) + goto out; + + error = set_lock_args(mode, lksb, flags, namelen, parent_lkid, ast, + astarg, bast, range, &args); + if (error) + goto out_put; + + if (convert) + error = convert_lock(ls, lkb, &args); + else + error = request_lock(ls, lkb, name, namelen, &args); + + if (error == -EINPROGRESS) + error = 0; + out_put: + if (convert || error) + put_lkb(lkb); + if (error == -EAGAIN) + error = 0; + out: + unlock_recovery(ls); + dlm_put_lockspace(ls); + return error; +} + +int dlm_unlock(dlm_lockspace_t *lockspace, + uint32_t lkid, + uint32_t flags, + struct dlm_lksb *lksb, + void *astarg) +{ + struct dlm_ls *ls; + struct dlm_lkb *lkb; + struct dlm_args args; + int error; + + ls = dlm_find_lockspace_local(lockspace); + if (!ls) + return -EINVAL; + + lock_recovery(ls); + + error = find_lkb(ls, lkid, &lkb); + if (error) + goto out; + + error = set_unlock_args(flags, astarg, &args); + if (error) + goto out_put; + + if (flags & DLM_LKF_CANCEL) + error = cancel_lock(ls, lkb, &args); + else + error = unlock_lock(ls, lkb, &args); + + if (error == -DLM_EUNLOCK || error == -DLM_ECANCEL) + error = 0; + out_put: + put_lkb(lkb); + out: + unlock_recovery(ls); + dlm_put_lockspace(ls); + return error; +} + +/* + * send/receive routines for remote operations and replies + * + * send_args + * send_common + * send_request receive_request + * send_convert receive_convert + * send_unlock receive_unlock + * send_cancel receive_cancel + * send_grant receive_grant + * send_bast receive_bast + * send_lookup receive_lookup + * send_remove receive_remove + * + * send_common_reply + * receive_request_reply send_request_reply + * receive_convert_reply send_convert_reply + * receive_unlock_reply send_unlock_reply + * receive_cancel_reply send_cancel_reply + * receive_lookup_reply send_lookup_reply + */ + +static int create_message(struct dlm_rsb *r, struct dlm_lkb *lkb, + int to_nodeid, int mstype, + struct dlm_message **ms_ret, + struct dlm_mhandle **mh_ret) +{ + struct dlm_message *ms; + struct dlm_mhandle *mh; + char *mb; + int mb_len = sizeof(struct dlm_message); + + switch (mstype) { + case DLM_MSG_REQUEST: + case DLM_MSG_LOOKUP: + case DLM_MSG_REMOVE: + mb_len += r->res_length; + break; + case DLM_MSG_CONVERT: + case DLM_MSG_UNLOCK: + case DLM_MSG_REQUEST_REPLY: + case DLM_MSG_CONVERT_REPLY: + case DLM_MSG_GRANT: + if (lkb && lkb->lkb_lvbptr) + mb_len += r->res_ls->ls_lvblen; + break; + } + + /* get_buffer gives us a message handle (mh) that we need to + pass into lowcomms_commit and a message buffer (mb) that we + write our data into */ + + mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb); + if (!mh) + return -ENOBUFS; + + memset(mb, 0, mb_len); + + ms = (struct dlm_message *) mb; + + ms->m_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR); + ms->m_header.h_lockspace = r->res_ls->ls_global_id; + ms->m_header.h_nodeid = dlm_our_nodeid(); + ms->m_header.h_length = mb_len; + ms->m_header.h_cmd = DLM_MSG; + + ms->m_type = mstype; + + *mh_ret = mh; + *ms_ret = ms; + return 0; +} + +/* further lowcomms enhancements or alternate implementations may make + the return value from this function useful at some point */ + +static int send_message(struct dlm_mhandle *mh, struct dlm_message *ms) +{ + dlm_message_out(ms); + dlm_lowcomms_commit_buffer(mh); + return 0; +} + +static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + ms->m_nodeid = lkb->lkb_nodeid; + ms->m_pid = lkb->lkb_ownpid; + ms->m_lkid = lkb->lkb_id; + ms->m_remid = lkb->lkb_remid; + ms->m_exflags = lkb->lkb_exflags; + ms->m_sbflags = lkb->lkb_sbflags; + ms->m_flags = lkb->lkb_flags; + ms->m_lvbseq = lkb->lkb_lvbseq; + ms->m_status = lkb->lkb_status; + ms->m_grmode = lkb->lkb_grmode; + ms->m_rqmode = lkb->lkb_rqmode; + ms->m_hash = r->res_hash; + + /* m_result and m_bastmode are set from function args, + not from lkb fields */ + + if (lkb->lkb_bastaddr) + ms->m_asts |= AST_BAST; + if (lkb->lkb_astaddr) + ms->m_asts |= AST_COMP; + + if (lkb->lkb_range) { + ms->m_range[0] = lkb->lkb_range[RQ_RANGE_START]; + ms->m_range[1] = lkb->lkb_range[RQ_RANGE_END]; + } + + if (ms->m_type == DLM_MSG_REQUEST || ms->m_type == DLM_MSG_LOOKUP) + memcpy(ms->m_extra, r->res_name, r->res_length); + + else if (lkb->lkb_lvbptr) + memcpy(ms->m_extra, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); + +} + +static int send_common(struct dlm_rsb *r, struct dlm_lkb *lkb, int mstype) +{ + struct dlm_message *ms; + struct dlm_mhandle *mh; + int to_nodeid, error; + + add_to_waiters(lkb, mstype); + + to_nodeid = r->res_nodeid; + + error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh); + if (error) + goto fail; + + send_args(r, lkb, ms); + + error = send_message(mh, ms); + if (error) + goto fail; + return 0; + + fail: + remove_from_waiters(lkb); + return error; +} + +static int send_request(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + return send_common(r, lkb, DLM_MSG_REQUEST); +} + +static int send_convert(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + int error; + + error = send_common(r, lkb, DLM_MSG_CONVERT); + + /* down conversions go without a reply from the master */ + if (!error && down_conversion(lkb)) { + remove_from_waiters(lkb); + r->res_ls->ls_stub_ms.m_result = 0; + __receive_convert_reply(r, lkb, &r->res_ls->ls_stub_ms); + } + + return error; +} + +/* FIXME: if this lkb is the only lock we hold on the rsb, then set + MASTER_UNCERTAIN to force the next request on the rsb to confirm + that the master is still correct. */ + +static int send_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + return send_common(r, lkb, DLM_MSG_UNLOCK); +} + +static int send_cancel(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + return send_common(r, lkb, DLM_MSG_CANCEL); +} + +static int send_grant(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + struct dlm_message *ms; + struct dlm_mhandle *mh; + int to_nodeid, error; + + to_nodeid = lkb->lkb_nodeid; + + error = create_message(r, lkb, to_nodeid, DLM_MSG_GRANT, &ms, &mh); + if (error) + goto out; + + send_args(r, lkb, ms); + + ms->m_result = 0; + + error = send_message(mh, ms); + out: + return error; +} + +static int send_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int mode) +{ + struct dlm_message *ms; + struct dlm_mhandle *mh; + int to_nodeid, error; + + to_nodeid = lkb->lkb_nodeid; + + error = create_message(r, NULL, to_nodeid, DLM_MSG_BAST, &ms, &mh); + if (error) + goto out; + + send_args(r, lkb, ms); + + ms->m_bastmode = mode; + + error = send_message(mh, ms); + out: + return error; +} + +static int send_lookup(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + struct dlm_message *ms; + struct dlm_mhandle *mh; + int to_nodeid, error; + + add_to_waiters(lkb, DLM_MSG_LOOKUP); + + to_nodeid = dlm_dir_nodeid(r); + + error = create_message(r, NULL, to_nodeid, DLM_MSG_LOOKUP, &ms, &mh); + if (error) + goto fail; + + send_args(r, lkb, ms); + + error = send_message(mh, ms); + if (error) + goto fail; + return 0; + + fail: + remove_from_waiters(lkb); + return error; +} + +static int send_remove(struct dlm_rsb *r) +{ + struct dlm_message *ms; + struct dlm_mhandle *mh; + int to_nodeid, error; + + to_nodeid = dlm_dir_nodeid(r); + + error = create_message(r, NULL, to_nodeid, DLM_MSG_REMOVE, &ms, &mh); + if (error) + goto out; + + memcpy(ms->m_extra, r->res_name, r->res_length); + ms->m_hash = r->res_hash; + + error = send_message(mh, ms); + out: + return error; +} + +static int send_common_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, + int mstype, int rv) +{ + struct dlm_message *ms; + struct dlm_mhandle *mh; + int to_nodeid, error; + + to_nodeid = lkb->lkb_nodeid; + + error = create_message(r, lkb, to_nodeid, mstype, &ms, &mh); + if (error) + goto out; + + send_args(r, lkb, ms); + + ms->m_result = rv; + + error = send_message(mh, ms); + out: + return error; +} + +static int send_request_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) +{ + return send_common_reply(r, lkb, DLM_MSG_REQUEST_REPLY, rv); +} + +static int send_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) +{ + return send_common_reply(r, lkb, DLM_MSG_CONVERT_REPLY, rv); +} + +static int send_unlock_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) +{ + return send_common_reply(r, lkb, DLM_MSG_UNLOCK_REPLY, rv); +} + +static int send_cancel_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv) +{ + return send_common_reply(r, lkb, DLM_MSG_CANCEL_REPLY, rv); +} + +static int send_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms_in, + int ret_nodeid, int rv) +{ + struct dlm_rsb *r = &ls->ls_stub_rsb; + struct dlm_message *ms; + struct dlm_mhandle *mh; + int error, nodeid = ms_in->m_header.h_nodeid; + + error = create_message(r, NULL, nodeid, DLM_MSG_LOOKUP_REPLY, &ms, &mh); + if (error) + goto out; + + ms->m_lkid = ms_in->m_lkid; + ms->m_result = rv; + ms->m_nodeid = ret_nodeid; + + error = send_message(mh, ms); + out: + return error; +} + +/* which args we save from a received message depends heavily on the type + of message, unlike the send side where we can safely send everything about + the lkb for any type of message */ + +static void receive_flags(struct dlm_lkb *lkb, struct dlm_message *ms) +{ + lkb->lkb_exflags = ms->m_exflags; + lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) | + (ms->m_flags & 0x0000FFFF); +} + +static void receive_flags_reply(struct dlm_lkb *lkb, struct dlm_message *ms) +{ + lkb->lkb_sbflags = ms->m_sbflags; + lkb->lkb_flags = (lkb->lkb_flags & 0xFFFF0000) | + (ms->m_flags & 0x0000FFFF); +} + +static int receive_extralen(struct dlm_message *ms) +{ + return (ms->m_header.h_length - sizeof(struct dlm_message)); +} + +static int receive_range(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + if (lkb->lkb_flags & DLM_IFL_RANGE) { + if (!lkb->lkb_range) + lkb->lkb_range = allocate_range(ls); + if (!lkb->lkb_range) + return -ENOMEM; + lkb->lkb_range[RQ_RANGE_START] = ms->m_range[0]; + lkb->lkb_range[RQ_RANGE_END] = ms->m_range[1]; + } + return 0; +} + +static int receive_lvb(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + int len; + + if (lkb->lkb_exflags & DLM_LKF_VALBLK) { + if (!lkb->lkb_lvbptr) + lkb->lkb_lvbptr = allocate_lvb(ls); + if (!lkb->lkb_lvbptr) + return -ENOMEM; + len = receive_extralen(ms); + memcpy(lkb->lkb_lvbptr, ms->m_extra, len); + } + return 0; +} + +static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + lkb->lkb_nodeid = ms->m_header.h_nodeid; + lkb->lkb_ownpid = ms->m_pid; + lkb->lkb_remid = ms->m_lkid; + lkb->lkb_grmode = DLM_LOCK_IV; + lkb->lkb_rqmode = ms->m_rqmode; + lkb->lkb_bastaddr = (void *) (long) (ms->m_asts & AST_BAST); + lkb->lkb_astaddr = (void *) (long) (ms->m_asts & AST_COMP); + + DLM_ASSERT(is_master_copy(lkb), dlm_print_lkb(lkb);); + + if (receive_range(ls, lkb, ms)) + return -ENOMEM; + + if (receive_lvb(ls, lkb, ms)) + return -ENOMEM; + + return 0; +} + +static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + if (lkb->lkb_nodeid != ms->m_header.h_nodeid) { + log_error(ls, "convert_args nodeid %d %d lkid %x %x", + lkb->lkb_nodeid, ms->m_header.h_nodeid, + lkb->lkb_id, lkb->lkb_remid); + return -EINVAL; + } + + if (!is_master_copy(lkb)) + return -EINVAL; + + if (lkb->lkb_status != DLM_LKSTS_GRANTED) + return -EBUSY; + + if (receive_range(ls, lkb, ms)) + return -ENOMEM; + if (lkb->lkb_range) { + lkb->lkb_range[GR_RANGE_START] = 0LL; + lkb->lkb_range[GR_RANGE_END] = 0xffffffffffffffffULL; + } + + if (receive_lvb(ls, lkb, ms)) + return -ENOMEM; + + lkb->lkb_rqmode = ms->m_rqmode; + lkb->lkb_lvbseq = ms->m_lvbseq; + + return 0; +} + +static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + if (!is_master_copy(lkb)) + return -EINVAL; + if (receive_lvb(ls, lkb, ms)) + return -ENOMEM; + return 0; +} + +/* We fill in the stub-lkb fields with the info that send_xxxx_reply() + uses to send a reply and that the remote end uses to process the reply. */ + +static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb = &ls->ls_stub_lkb; + lkb->lkb_nodeid = ms->m_header.h_nodeid; + lkb->lkb_remid = ms->m_lkid; +} + +static void receive_request(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error, namelen; + + error = create_lkb(ls, &lkb); + if (error) + goto fail; + + receive_flags(lkb, ms); + lkb->lkb_flags |= DLM_IFL_MSTCPY; + error = receive_request_args(ls, lkb, ms); + if (error) { + put_lkb(lkb); + goto fail; + } + + namelen = receive_extralen(ms); + + error = find_rsb(ls, ms->m_extra, namelen, R_MASTER, &r); + if (error) { + put_lkb(lkb); + goto fail; + } + + lock_rsb(r); + + attach_lkb(r, lkb); + error = do_request(r, lkb); + send_request_reply(r, lkb, error); + + unlock_rsb(r); + put_rsb(r); + + if (error == -EINPROGRESS) + error = 0; + if (error) + put_lkb(lkb); + return; + + fail: + setup_stub_lkb(ls, ms); + send_request_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); +} + +static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error, reply = TRUE; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) + goto fail; + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + receive_flags(lkb, ms); + error = receive_convert_args(ls, lkb, ms); + if (error) + goto out; + reply = !down_conversion(lkb); + + error = do_convert(r, lkb); + out: + if (reply) + send_convert_reply(r, lkb, error); + + unlock_rsb(r); + put_rsb(r); + put_lkb(lkb); + return; + + fail: + setup_stub_lkb(ls, ms); + send_convert_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); +} + +static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) + goto fail; + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + receive_flags(lkb, ms); + error = receive_unlock_args(ls, lkb, ms); + if (error) + goto out; + + error = do_unlock(r, lkb); + out: + send_unlock_reply(r, lkb, error); + + unlock_rsb(r); + put_rsb(r); + put_lkb(lkb); + return; + + fail: + setup_stub_lkb(ls, ms); + send_unlock_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); +} + +static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) + goto fail; + + receive_flags(lkb, ms); + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + error = do_cancel(r, lkb); + send_cancel_reply(r, lkb, error); + + unlock_rsb(r); + put_rsb(r); + put_lkb(lkb); + return; + + fail: + setup_stub_lkb(ls, ms); + send_cancel_reply(&ls->ls_stub_rsb, &ls->ls_stub_lkb, error); +} + +static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) { + log_error(ls, "receive_grant no lkb"); + return; + } + DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + receive_flags_reply(lkb, ms); + grant_lock_pc(r, lkb, ms); + queue_cast(r, lkb, 0); + + unlock_rsb(r); + put_rsb(r); + put_lkb(lkb); +} + +static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) { + log_error(ls, "receive_bast no lkb"); + return; + } + DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); + + r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + queue_bast(r, lkb, ms->m_bastmode); + + unlock_rsb(r); + put_rsb(r); + put_lkb(lkb); +} + +static void receive_lookup(struct dlm_ls *ls, struct dlm_message *ms) +{ + int len, error, ret_nodeid, dir_nodeid, from_nodeid, our_nodeid; + + from_nodeid = ms->m_header.h_nodeid; + our_nodeid = dlm_our_nodeid(); + + len = receive_extralen(ms); + + dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash); + if (dir_nodeid != our_nodeid) { + log_error(ls, "lookup dir_nodeid %d from %d", + dir_nodeid, from_nodeid); + error = -EINVAL; + ret_nodeid = -1; + goto out; + } + + error = dlm_dir_lookup(ls, from_nodeid, ms->m_extra, len, &ret_nodeid); + + /* Optimization: we're master so treat lookup as a request */ + if (!error && ret_nodeid == our_nodeid) { + receive_request(ls, ms); + return; + } + out: + send_lookup_reply(ls, ms, ret_nodeid, error); +} + +static void receive_remove(struct dlm_ls *ls, struct dlm_message *ms) +{ + int len, dir_nodeid, from_nodeid; + + from_nodeid = ms->m_header.h_nodeid; + + len = receive_extralen(ms); + + dir_nodeid = dlm_hash2nodeid(ls, ms->m_hash); + if (dir_nodeid != dlm_our_nodeid()) { + log_error(ls, "remove dir entry dir_nodeid %d from %d", + dir_nodeid, from_nodeid); + return; + } + + dlm_dir_remove_entry(ls, from_nodeid, ms->m_extra, len); +} + +static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error, mstype; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) { + log_error(ls, "receive_request_reply no lkb"); + return; + } + DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); + + mstype = lkb->lkb_wait_type; + error = remove_from_waiters(lkb); + if (error) { + log_error(ls, "receive_request_reply not on waiters"); + goto out; + } + + /* this is the value returned from do_request() on the master */ + error = ms->m_result; + + r = lkb->lkb_resource; + hold_rsb(r); + lock_rsb(r); + + /* Optimization: the dir node was also the master, so it took our + lookup as a request and sent request reply instead of lookup reply */ + if (mstype == DLM_MSG_LOOKUP) { + r->res_nodeid = ms->m_header.h_nodeid; + lkb->lkb_nodeid = r->res_nodeid; + } + + switch (error) { + case -EAGAIN: + /* request would block (be queued) on remote master; + the unhold undoes the original ref from create_lkb() + so it leads to the lkb being freed */ + queue_cast(r, lkb, -EAGAIN); + confirm_master(r, -EAGAIN); + unhold_lkb(lkb); + break; + + case -EINPROGRESS: + case 0: + /* request was queued or granted on remote master */ + receive_flags_reply(lkb, ms); + lkb->lkb_remid = ms->m_lkid; + if (error) + add_lkb(r, lkb, DLM_LKSTS_WAITING); + else { + grant_lock_pc(r, lkb, ms); + queue_cast(r, lkb, 0); + } + confirm_master(r, error); + break; + + case -ENOENT: + case -ENOTBLK: + /* find_rsb failed to find rsb or rsb wasn't master */ + r->res_nodeid = -1; + lkb->lkb_nodeid = -1; + _request_lock(r, lkb); + break; + + default: + log_error(ls, "receive_request_reply error %d", error); + } + + unlock_rsb(r); + put_rsb(r); + out: + put_lkb(lkb); +} + +static void __receive_convert_reply(struct dlm_rsb *r, struct dlm_lkb *lkb, + struct dlm_message *ms) +{ + int error = ms->m_result; + + /* this is the value returned from do_convert() on the master */ + + switch (error) { + case -EAGAIN: + /* convert would block (be queued) on remote master */ + queue_cast(r, lkb, -EAGAIN); + break; + + case -EINPROGRESS: + /* convert was queued on remote master */ + del_lkb(r, lkb); + add_lkb(r, lkb, DLM_LKSTS_CONVERT); + break; + + case 0: + /* convert was granted on remote master */ + receive_flags_reply(lkb, ms); + grant_lock_pc(r, lkb, ms); + queue_cast(r, lkb, 0); + break; + + default: + log_error(r->res_ls, "receive_convert_reply error %d", error); + } +} + +static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms) +{ + struct dlm_rsb *r = lkb->lkb_resource; + + hold_rsb(r); + lock_rsb(r); + + __receive_convert_reply(r, lkb, ms); + + unlock_rsb(r); + put_rsb(r); +} + +static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + int error; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) { + log_error(ls, "receive_convert_reply no lkb"); + return; + } + DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); + + error = remove_from_waiters(lkb); + if (error) { + log_error(ls, "receive_convert_reply not on waiters"); + goto out; + } + + _receive_convert_reply(lkb, ms); + out: + put_lkb(lkb); +} + +static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms) +{ + struct dlm_rsb *r = lkb->lkb_resource; + int error = ms->m_result; + + hold_rsb(r); + lock_rsb(r); + + /* this is the value returned from do_unlock() on the master */ + + switch (error) { + case -DLM_EUNLOCK: + receive_flags_reply(lkb, ms); + remove_lock_pc(r, lkb); + queue_cast(r, lkb, -DLM_EUNLOCK); + break; + default: + log_error(r->res_ls, "receive_unlock_reply error %d", error); + } + + unlock_rsb(r); + put_rsb(r); +} + +static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + int error; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) { + log_error(ls, "receive_unlock_reply no lkb"); + return; + } + DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); + + error = remove_from_waiters(lkb); + if (error) { + log_error(ls, "receive_unlock_reply not on waiters"); + goto out; + } + + _receive_unlock_reply(lkb, ms); + out: + put_lkb(lkb); +} + +static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms) +{ + struct dlm_rsb *r = lkb->lkb_resource; + int error = ms->m_result; + + hold_rsb(r); + lock_rsb(r); + + /* this is the value returned from do_cancel() on the master */ + + switch (error) { + case -DLM_ECANCEL: + receive_flags_reply(lkb, ms); + revert_lock_pc(r, lkb); + queue_cast(r, lkb, -DLM_ECANCEL); + break; + default: + log_error(r->res_ls, "receive_cancel_reply error %d", error); + } + + unlock_rsb(r); + put_rsb(r); +} + +static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + int error; + + error = find_lkb(ls, ms->m_remid, &lkb); + if (error) { + log_error(ls, "receive_cancel_reply no lkb"); + return; + } + DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); + + error = remove_from_waiters(lkb); + if (error) { + log_error(ls, "receive_cancel_reply not on waiters"); + goto out; + } + + _receive_cancel_reply(lkb, ms); + out: + put_lkb(lkb); +} + +static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error, ret_nodeid; + + error = find_lkb(ls, ms->m_lkid, &lkb); + if (error) { + log_error(ls, "receive_lookup_reply no lkb"); + return; + } + + error = remove_from_waiters(lkb); + if (error) { + log_error(ls, "receive_lookup_reply not on waiters"); + goto out; + } + + /* this is the value returned by dlm_dir_lookup on dir node + FIXME: will a non-zero error ever be returned? */ + error = ms->m_result; + + r = lkb->lkb_resource; + hold_rsb(r); + lock_rsb(r); + + ret_nodeid = ms->m_nodeid; + if (ret_nodeid == dlm_our_nodeid()) { + r->res_nodeid = 0; + ret_nodeid = 0; + r->res_first_lkid = 0; + } else { + /* set_master() will copy res_nodeid to lkb_nodeid */ + r->res_nodeid = ret_nodeid; + } + + _request_lock(r, lkb); + + if (!ret_nodeid) + process_lookup_list(r); + + unlock_rsb(r); + put_rsb(r); + out: + put_lkb(lkb); +} + +int dlm_receive_message(struct dlm_header *hd, int nodeid, int recovery) +{ + struct dlm_message *ms = (struct dlm_message *) hd; + struct dlm_ls *ls; + int error; + + if (!recovery) + dlm_message_in(ms); + + ls = dlm_find_lockspace_global(hd->h_lockspace); + if (!ls) { + log_print("drop message %d from %d for unknown lockspace %d", + ms->m_type, nodeid, hd->h_lockspace); + return -EINVAL; + } + + /* recovery may have just ended leaving a bunch of backed-up requests + in the requestqueue; wait while dlm_recoverd clears them */ + + if (!recovery) + dlm_wait_requestqueue(ls); + + /* recovery may have just started while there were a bunch of + in-flight requests -- save them in requestqueue to be processed + after recovery. we can't let dlm_recvd block on the recovery + lock. if dlm_recoverd is calling this function to clear the + requestqueue, it needs to be interrupted (-EINTR) if another + recovery operation is starting. */ + + while (1) { + if (dlm_locking_stopped(ls)) { + if (!recovery) + dlm_add_requestqueue(ls, nodeid, hd); + error = -EINTR; + goto out; + } + + if (lock_recovery_try(ls)) + break; + schedule(); + } + + switch (ms->m_type) { + + /* messages sent to a master node */ + + case DLM_MSG_REQUEST: + receive_request(ls, ms); + break; + + case DLM_MSG_CONVERT: + receive_convert(ls, ms); + break; + + case DLM_MSG_UNLOCK: + receive_unlock(ls, ms); + break; + + case DLM_MSG_CANCEL: + receive_cancel(ls, ms); + break; + + /* messages sent from a master node (replies to above) */ + + case DLM_MSG_REQUEST_REPLY: + receive_request_reply(ls, ms); + break; + + case DLM_MSG_CONVERT_REPLY: + receive_convert_reply(ls, ms); + break; + + case DLM_MSG_UNLOCK_REPLY: + receive_unlock_reply(ls, ms); + break; + + case DLM_MSG_CANCEL_REPLY: + receive_cancel_reply(ls, ms); + break; + + /* messages sent from a master node (only two types of async msg) */ + + case DLM_MSG_GRANT: + receive_grant(ls, ms); + break; + + case DLM_MSG_BAST: + receive_bast(ls, ms); + break; + + /* messages sent to a dir node */ + + case DLM_MSG_LOOKUP: + receive_lookup(ls, ms); + break; + + case DLM_MSG_REMOVE: + receive_remove(ls, ms); + break; + + /* messages sent from a dir node (remove has no reply) */ + + case DLM_MSG_LOOKUP_REPLY: + receive_lookup_reply(ls, ms); + break; + + default: + log_error(ls, "unknown message type %d", ms->m_type); + } + + unlock_recovery(ls); + out: + dlm_put_lockspace(ls); + dlm_astd_wake(); + return 0; +} + + +/* + * Recovery related + */ + +static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb) +{ + if (middle_conversion(lkb)) { + hold_lkb(lkb); + ls->ls_stub_ms.m_result = -EINPROGRESS; + _remove_from_waiters(lkb); + _receive_convert_reply(lkb, &ls->ls_stub_ms); + + /* Same special case as in receive_rcom_lock_args() */ + lkb->lkb_grmode = DLM_LOCK_IV; + rsb_set_flag(lkb->lkb_resource, RSB_RECOVER_CONVERT); + unhold_lkb(lkb); + + } else if (lkb->lkb_rqmode >= lkb->lkb_grmode) { + lkb->lkb_flags |= DLM_IFL_RESEND; + } + + /* lkb->lkb_rqmode < lkb->lkb_grmode shouldn't happen since down + conversions are async; there's no reply from the remote master */ +} + +/* A waiting lkb needs recovery if the master node has failed, or + the master node is changing (only when no directory is used) */ + +static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb) +{ + if (dlm_is_removed(ls, lkb->lkb_nodeid)) + return 1; + + if (!dlm_no_directory(ls)) + return 0; + + if (dlm_dir_nodeid(lkb->lkb_resource) != lkb->lkb_nodeid) + return 1; + + return 0; +} + +/* Recovery for locks that are waiting for replies from nodes that are now + gone. We can just complete unlocks and cancels by faking a reply from the + dead node. Requests and up-conversions we flag to be resent after + recovery. Down-conversions can just be completed with a fake reply like + unlocks. Conversions between PR and CW need special attention. */ + +void dlm_recover_waiters_pre(struct dlm_ls *ls) +{ + struct dlm_lkb *lkb, *safe; + + down(&ls->ls_waiters_sem); + + list_for_each_entry_safe(lkb, safe, &ls->ls_waiters, lkb_wait_reply) { + log_debug(ls, "pre recover waiter lkid %x type %d flags %x", + lkb->lkb_id, lkb->lkb_wait_type, lkb->lkb_flags); + + /* all outstanding lookups, regardless of destination will be + resent after recovery is done */ + + if (lkb->lkb_wait_type == DLM_MSG_LOOKUP) { + lkb->lkb_flags |= DLM_IFL_RESEND; + continue; + } + + if (!waiter_needs_recovery(ls, lkb)) + continue; + + switch (lkb->lkb_wait_type) { + + case DLM_MSG_REQUEST: + lkb->lkb_flags |= DLM_IFL_RESEND; + break; + + case DLM_MSG_CONVERT: + recover_convert_waiter(ls, lkb); + break; + + case DLM_MSG_UNLOCK: + hold_lkb(lkb); + ls->ls_stub_ms.m_result = -DLM_EUNLOCK; + _remove_from_waiters(lkb); + _receive_unlock_reply(lkb, &ls->ls_stub_ms); + put_lkb(lkb); + break; + + case DLM_MSG_CANCEL: + hold_lkb(lkb); + ls->ls_stub_ms.m_result = -DLM_ECANCEL; + _remove_from_waiters(lkb); + _receive_cancel_reply(lkb, &ls->ls_stub_ms); + put_lkb(lkb); + break; + + default: + log_error(ls, "invalid lkb wait_type %d", + lkb->lkb_wait_type); + } + } + up(&ls->ls_waiters_sem); +} + +static int remove_resend_waiter(struct dlm_ls *ls, struct dlm_lkb **lkb_ret) +{ + struct dlm_lkb *lkb; + int rv = 0; + + down(&ls->ls_waiters_sem); + list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) { + if (lkb->lkb_flags & DLM_IFL_RESEND) { + rv = lkb->lkb_wait_type; + _remove_from_waiters(lkb); + lkb->lkb_flags &= ~DLM_IFL_RESEND; + break; + } + } + up(&ls->ls_waiters_sem); + + if (!rv) + lkb = NULL; + *lkb_ret = lkb; + return rv; +} + +/* Deal with lookups and lkb's marked RESEND from _pre. We may now be the + master or dir-node for r. Processing the lkb may result in it being placed + back on waiters. */ + +int dlm_recover_waiters_post(struct dlm_ls *ls) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *r; + int error = 0, mstype; + + while (1) { + if (dlm_locking_stopped(ls)) { + log_debug(ls, "recover_waiters_post aborted"); + error = -EINTR; + break; + } + + mstype = remove_resend_waiter(ls, &lkb); + if (!mstype) + break; + + r = lkb->lkb_resource; + + log_debug(ls, "recover_waiters_post %x type %d flags %x %s", + lkb->lkb_id, mstype, lkb->lkb_flags, r->res_name); + + switch (mstype) { + + case DLM_MSG_LOOKUP: + hold_rsb(r); + lock_rsb(r); + _request_lock(r, lkb); + if (is_master(r)) + confirm_master(r, 0); + unlock_rsb(r); + put_rsb(r); + break; + + case DLM_MSG_REQUEST: + hold_rsb(r); + lock_rsb(r); + _request_lock(r, lkb); + unlock_rsb(r); + put_rsb(r); + break; + + case DLM_MSG_CONVERT: + hold_rsb(r); + lock_rsb(r); + _convert_lock(r, lkb); + unlock_rsb(r); + put_rsb(r); + break; + + default: + log_error(ls, "recover_waiters_post type %d", mstype); + } + } + + return error; +} + +static void purge_queue(struct dlm_rsb *r, struct list_head *queue, + int (*test)(struct dlm_ls *ls, struct dlm_lkb *lkb)) +{ + struct dlm_ls *ls = r->res_ls; + struct dlm_lkb *lkb, *safe; + + list_for_each_entry_safe(lkb, safe, queue, lkb_statequeue) { + if (test(ls, lkb)) { + del_lkb(r, lkb); + /* this put should free the lkb */ + if (!put_lkb(lkb)) + log_error(ls, "purged lkb not released"); + } + } +} + +static int purge_dead_test(struct dlm_ls *ls, struct dlm_lkb *lkb) +{ + return (is_master_copy(lkb) && dlm_is_removed(ls, lkb->lkb_nodeid)); +} + +static int purge_mstcpy_test(struct dlm_ls *ls, struct dlm_lkb *lkb) +{ + return is_master_copy(lkb); +} + +static void purge_dead_locks(struct dlm_rsb *r) +{ + purge_queue(r, &r->res_grantqueue, &purge_dead_test); + purge_queue(r, &r->res_convertqueue, &purge_dead_test); + purge_queue(r, &r->res_waitqueue, &purge_dead_test); +} + +void dlm_purge_mstcpy_locks(struct dlm_rsb *r) +{ + purge_queue(r, &r->res_grantqueue, &purge_mstcpy_test); + purge_queue(r, &r->res_convertqueue, &purge_mstcpy_test); + purge_queue(r, &r->res_waitqueue, &purge_mstcpy_test); +} + +/* Get rid of locks held by nodes that are gone. */ + +int dlm_purge_locks(struct dlm_ls *ls) +{ + struct dlm_rsb *r; + + log_debug(ls, "dlm_purge_locks"); + + down_write(&ls->ls_root_sem); + list_for_each_entry(r, &ls->ls_root_list, res_root_list) { + hold_rsb(r); + lock_rsb(r); + if (is_master(r)) + purge_dead_locks(r); + unlock_rsb(r); + unhold_rsb(r); + + schedule(); + } + up_write(&ls->ls_root_sem); + + return 0; +} + +int dlm_grant_after_purge(struct dlm_ls *ls) +{ + struct dlm_rsb *r; + int i; + + for (i = 0; i < ls->ls_rsbtbl_size; i++) { + read_lock(&ls->ls_rsbtbl[i].lock); + list_for_each_entry(r, &ls->ls_rsbtbl[i].list, res_hashchain) { + hold_rsb(r); + lock_rsb(r); + if (is_master(r)) { + grant_pending_locks(r); + confirm_master(r, 0); + } + unlock_rsb(r); + put_rsb(r); + } + read_unlock(&ls->ls_rsbtbl[i].lock); + } + + return 0; +} + +static struct dlm_lkb *search_remid_list(struct list_head *head, int nodeid, + uint32_t remid) +{ + struct dlm_lkb *lkb; + + list_for_each_entry(lkb, head, lkb_statequeue) { + if (lkb->lkb_nodeid == nodeid && lkb->lkb_remid == remid) + return lkb; + } + return NULL; +} + +static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid, + uint32_t remid) +{ + struct dlm_lkb *lkb; + + lkb = search_remid_list(&r->res_grantqueue, nodeid, remid); + if (lkb) + return lkb; + lkb = search_remid_list(&r->res_convertqueue, nodeid, remid); + if (lkb) + return lkb; + lkb = search_remid_list(&r->res_waitqueue, nodeid, remid); + if (lkb) + return lkb; + return NULL; +} + +static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb, + struct dlm_rsb *r, struct dlm_rcom *rc) +{ + struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; + int lvblen; + + lkb->lkb_nodeid = rc->rc_header.h_nodeid; + lkb->lkb_ownpid = rl->rl_ownpid; + lkb->lkb_remid = rl->rl_lkid; + lkb->lkb_exflags = rl->rl_exflags; + lkb->lkb_flags = rl->rl_flags & 0x0000FFFF; + lkb->lkb_flags |= DLM_IFL_MSTCPY; + lkb->lkb_lvbseq = rl->rl_lvbseq; + lkb->lkb_rqmode = rl->rl_rqmode; + lkb->lkb_grmode = rl->rl_grmode; + /* don't set lkb_status because add_lkb wants to itself */ + + lkb->lkb_bastaddr = (void *) (long) (rl->rl_asts & AST_BAST); + lkb->lkb_astaddr = (void *) (long) (rl->rl_asts & AST_COMP); + + if (lkb->lkb_flags & DLM_IFL_RANGE) { + lkb->lkb_range = allocate_range(ls); + if (!lkb->lkb_range) + return -ENOMEM; + memcpy(lkb->lkb_range, rl->rl_range, 4*sizeof(uint64_t)); + } + + if (lkb->lkb_exflags & DLM_LKF_VALBLK) { + lkb->lkb_lvbptr = allocate_lvb(ls); + if (!lkb->lkb_lvbptr) + return -ENOMEM; + lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) - + sizeof(struct rcom_lock); + memcpy(lkb->lkb_lvbptr, rl->rl_lvb, lvblen); + } + + /* Conversions between PR and CW (middle modes) need special handling. + The real granted mode of these converting locks cannot be determined + until all locks have been rebuilt on the rsb (recover_conversion) */ + + if (rl->rl_wait_type == DLM_MSG_CONVERT && middle_conversion(lkb)) { + rl->rl_status = DLM_LKSTS_CONVERT; + lkb->lkb_grmode = DLM_LOCK_IV; + rsb_set_flag(r, RSB_RECOVER_CONVERT); + } + + return 0; +} + +/* This lkb may have been recovered in a previous aborted recovery so we need + to check if the rsb already has an lkb with the given remote nodeid/lkid. + If so we just send back a standard reply. If not, we create a new lkb with + the given values and send back our lkid. We send back our lkid by sending + back the rcom_lock struct we got but with the remid field filled in. */ + +int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc) +{ + struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; + struct dlm_rsb *r; + struct dlm_lkb *lkb; + int error; + + if (rl->rl_parent_lkid) { + error = -EOPNOTSUPP; + goto out; + } + + error = find_rsb(ls, rl->rl_name, rl->rl_namelen, R_MASTER, &r); + if (error) + goto out; + + lock_rsb(r); + + lkb = search_remid(r, rc->rc_header.h_nodeid, rl->rl_lkid); + if (lkb) { + error = -EEXIST; + goto out_remid; + } + + error = create_lkb(ls, &lkb); + if (error) + goto out_unlock; + + error = receive_rcom_lock_args(ls, lkb, r, rc); + if (error) { + put_lkb(lkb); + goto out_unlock; + } + + attach_lkb(r, lkb); + add_lkb(r, lkb, rl->rl_status); + error = 0; + + out_remid: + /* this is the new value returned to the lock holder for + saving in its process-copy lkb */ + rl->rl_remid = lkb->lkb_id; + + out_unlock: + unlock_rsb(r); + put_rsb(r); + out: + if (error) + log_print("recover_master_copy %d %x", error, rl->rl_lkid); + rl->rl_result = error; + return error; +} + +int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc) +{ + struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf; + struct dlm_rsb *r; + struct dlm_lkb *lkb; + int error; + + error = find_lkb(ls, rl->rl_lkid, &lkb); + if (error) { + log_error(ls, "recover_process_copy no lkid %x", rl->rl_lkid); + return error; + } + + DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb);); + + error = rl->rl_result; + + r = lkb->lkb_resource; + hold_rsb(r); + lock_rsb(r); + + switch (error) { + case -EEXIST: + log_debug(ls, "master copy exists %x", lkb->lkb_id); + /* fall through */ + case 0: + lkb->lkb_remid = rl->rl_remid; + break; + default: + log_error(ls, "dlm_recover_process_copy unknown error %d %x", + error, lkb->lkb_id); + } + + /* an ack for dlm_recover_locks() which waits for replies from + all the locks it sends to new masters */ + dlm_recovered_lock(r); + + unlock_rsb(r); + put_rsb(r); + put_lkb(lkb); + + return 0; +} + diff --git a/fs/dlm/lock.h b/fs/dlm/lock.h new file mode 100644 index 000000000000..9e6499f773da --- /dev/null +++ b/fs/dlm/lock.h @@ -0,0 +1,50 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __LOCK_DOT_H__ +#define __LOCK_DOT_H__ + +void dlm_print_rsb(struct dlm_rsb *r); +int dlm_receive_message(struct dlm_header *hd, int nodeid, int recovery); +int dlm_modes_compat(int mode1, int mode2); +int dlm_find_rsb(struct dlm_ls *ls, char *name, int namelen, + unsigned int flags, struct dlm_rsb **r_ret); +void dlm_put_rsb(struct dlm_rsb *r); +void dlm_hold_rsb(struct dlm_rsb *r); +int dlm_put_lkb(struct dlm_lkb *lkb); +void dlm_scan_rsbs(struct dlm_ls *ls); + +int dlm_purge_locks(struct dlm_ls *ls); +void dlm_purge_mstcpy_locks(struct dlm_rsb *r); +int dlm_grant_after_purge(struct dlm_ls *ls); +int dlm_recover_waiters_post(struct dlm_ls *ls); +void dlm_recover_waiters_pre(struct dlm_ls *ls); +int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc); +int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc); + +static inline int is_master(struct dlm_rsb *r) +{ + return !r->res_nodeid; +} + +static inline void lock_rsb(struct dlm_rsb *r) +{ + down(&r->res_sem); +} + +static inline void unlock_rsb(struct dlm_rsb *r) +{ + up(&r->res_sem); +} + +#endif + diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c new file mode 100644 index 000000000000..fee4659b6582 --- /dev/null +++ b/fs/dlm/lockspace.c @@ -0,0 +1,666 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "member.h" +#include "recoverd.h" +#include "ast.h" +#include "dir.h" +#include "lowcomms.h" +#include "config.h" +#include "memory.h" +#include "lock.h" + +#ifdef CONFIG_DLM_DEBUG +int dlm_create_debug_file(struct dlm_ls *ls); +void dlm_delete_debug_file(struct dlm_ls *ls); +#else +static inline int dlm_create_debug_file(struct dlm_ls *ls) { return 0; } +static inline void dlm_delete_debug_file(struct dlm_ls *ls) { } +#endif + +static int ls_count; +static struct semaphore ls_lock; +static struct list_head lslist; +static spinlock_t lslist_lock; +static struct task_struct * scand_task; + + +static ssize_t dlm_control_store(struct dlm_ls *ls, const char *buf, size_t len) +{ + ssize_t ret = len; + int n = simple_strtol(buf, NULL, 0); + + switch (n) { + case 0: + dlm_ls_stop(ls); + break; + case 1: + dlm_ls_start(ls); + break; + default: + ret = -EINVAL; + } + return ret; +} + +static ssize_t dlm_event_store(struct dlm_ls *ls, const char *buf, size_t len) +{ + ls->ls_uevent_result = simple_strtol(buf, NULL, 0); + set_bit(LSFL_UEVENT_WAIT, &ls->ls_flags); + wake_up(&ls->ls_uevent_wait); + return len; +} + +static ssize_t dlm_id_show(struct dlm_ls *ls, char *buf) +{ + return sprintf(buf, "%u\n", ls->ls_global_id); +} + +static ssize_t dlm_id_store(struct dlm_ls *ls, const char *buf, size_t len) +{ + ls->ls_global_id = simple_strtoul(buf, NULL, 0); + return len; +} + +struct dlm_attr { + struct attribute attr; + ssize_t (*show)(struct dlm_ls *, char *); + ssize_t (*store)(struct dlm_ls *, const char *, size_t); +}; + +static struct dlm_attr dlm_attr_control = { + .attr = {.name = "control", .mode = S_IWUSR}, + .store = dlm_control_store +}; + +static struct dlm_attr dlm_attr_event = { + .attr = {.name = "event_done", .mode = S_IWUSR}, + .store = dlm_event_store +}; + +static struct dlm_attr dlm_attr_id = { + .attr = {.name = "id", .mode = S_IRUGO | S_IWUSR}, + .show = dlm_id_show, + .store = dlm_id_store +}; + +static struct attribute *dlm_attrs[] = { + &dlm_attr_control.attr, + &dlm_attr_event.attr, + &dlm_attr_id.attr, + NULL, +}; + +static ssize_t dlm_attr_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + struct dlm_ls *ls = container_of(kobj, struct dlm_ls, ls_kobj); + struct dlm_attr *a = container_of(attr, struct dlm_attr, attr); + return a->show ? a->show(ls, buf) : 0; +} + +static ssize_t dlm_attr_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t len) +{ + struct dlm_ls *ls = container_of(kobj, struct dlm_ls, ls_kobj); + struct dlm_attr *a = container_of(attr, struct dlm_attr, attr); + return a->store ? a->store(ls, buf, len) : len; +} + +static struct sysfs_ops dlm_attr_ops = { + .show = dlm_attr_show, + .store = dlm_attr_store, +}; + +static struct kobj_type dlm_ktype = { + .default_attrs = dlm_attrs, + .sysfs_ops = &dlm_attr_ops, +}; + +static struct kset dlm_kset = { + .subsys = &kernel_subsys, + .kobj = {.name = "dlm",}, + .ktype = &dlm_ktype, +}; + +static int kobject_setup(struct dlm_ls *ls) +{ + char lsname[DLM_LOCKSPACE_LEN]; + int error; + + memset(lsname, 0, DLM_LOCKSPACE_LEN); + snprintf(lsname, DLM_LOCKSPACE_LEN, "%s", ls->ls_name); + + error = kobject_set_name(&ls->ls_kobj, "%s", lsname); + if (error) + return error; + + ls->ls_kobj.kset = &dlm_kset; + ls->ls_kobj.ktype = &dlm_ktype; + return 0; +} + +static int do_uevent(struct dlm_ls *ls, int in) +{ + int error; + + if (in) + kobject_uevent(&ls->ls_kobj, KOBJ_ONLINE); + else + kobject_uevent(&ls->ls_kobj, KOBJ_OFFLINE); + + error = wait_event_interruptible(ls->ls_uevent_wait, + test_and_clear_bit(LSFL_UEVENT_WAIT, &ls->ls_flags)); + if (error) + goto out; + + error = ls->ls_uevent_result; + out: + return error; +} + + +int dlm_lockspace_init(void) +{ + int error; + + ls_count = 0; + init_MUTEX(&ls_lock); + INIT_LIST_HEAD(&lslist); + spin_lock_init(&lslist_lock); + + error = kset_register(&dlm_kset); + if (error) + printk("dlm_lockspace_init: cannot register kset %d\n", error); + return error; +} + +void dlm_lockspace_exit(void) +{ + kset_unregister(&dlm_kset); +} + +static int dlm_scand(void *data) +{ + struct dlm_ls *ls; + + while (!kthread_should_stop()) { + list_for_each_entry(ls, &lslist, ls_list) + dlm_scan_rsbs(ls); + schedule_timeout_interruptible(dlm_config.scan_secs * HZ); + } + return 0; +} + +static int dlm_scand_start(void) +{ + struct task_struct *p; + int error = 0; + + p = kthread_run(dlm_scand, NULL, "dlm_scand"); + if (IS_ERR(p)) + error = PTR_ERR(p); + else + scand_task = p; + return error; +} + +static void dlm_scand_stop(void) +{ + kthread_stop(scand_task); +} + +static struct dlm_ls *dlm_find_lockspace_name(char *name, int namelen) +{ + struct dlm_ls *ls; + + spin_lock(&lslist_lock); + + list_for_each_entry(ls, &lslist, ls_list) { + if (ls->ls_namelen == namelen && + memcmp(ls->ls_name, name, namelen) == 0) + goto out; + } + ls = NULL; + out: + spin_unlock(&lslist_lock); + return ls; +} + +struct dlm_ls *dlm_find_lockspace_global(uint32_t id) +{ + struct dlm_ls *ls; + + spin_lock(&lslist_lock); + + list_for_each_entry(ls, &lslist, ls_list) { + if (ls->ls_global_id == id) { + ls->ls_count++; + goto out; + } + } + ls = NULL; + out: + spin_unlock(&lslist_lock); + return ls; +} + +struct dlm_ls *dlm_find_lockspace_local(void *id) +{ + struct dlm_ls *ls = id; + + spin_lock(&lslist_lock); + ls->ls_count++; + spin_unlock(&lslist_lock); + return ls; +} + +void dlm_put_lockspace(struct dlm_ls *ls) +{ + spin_lock(&lslist_lock); + ls->ls_count--; + spin_unlock(&lslist_lock); +} + +static void remove_lockspace(struct dlm_ls *ls) +{ + for (;;) { + spin_lock(&lslist_lock); + if (ls->ls_count == 0) { + list_del(&ls->ls_list); + spin_unlock(&lslist_lock); + return; + } + spin_unlock(&lslist_lock); + ssleep(1); + } +} + +static int threads_start(void) +{ + int error; + + /* Thread which process lock requests for all lockspace's */ + error = dlm_astd_start(); + if (error) { + log_print("cannot start dlm_astd thread %d", error); + goto fail; + } + + error = dlm_scand_start(); + if (error) { + log_print("cannot start dlm_scand thread %d", error); + goto astd_fail; + } + + /* Thread for sending/receiving messages for all lockspace's */ + error = dlm_lowcomms_start(); + if (error) { + log_print("cannot start dlm lowcomms %d", error); + goto scand_fail; + } + + return 0; + + scand_fail: + dlm_scand_stop(); + astd_fail: + dlm_astd_stop(); + fail: + return error; +} + +static void threads_stop(void) +{ + dlm_scand_stop(); + dlm_lowcomms_stop(); + dlm_astd_stop(); +} + +static int new_lockspace(char *name, int namelen, void **lockspace, + uint32_t flags, int lvblen) +{ + struct dlm_ls *ls; + int i, size, error = -ENOMEM; + + if (namelen > DLM_LOCKSPACE_LEN) + return -EINVAL; + + if (!lvblen || (lvblen % 8)) + return -EINVAL; + + if (!try_module_get(THIS_MODULE)) + return -EINVAL; + + ls = dlm_find_lockspace_name(name, namelen); + if (ls) { + *lockspace = ls; + module_put(THIS_MODULE); + return -EEXIST; + } + + ls = kmalloc(sizeof(struct dlm_ls) + namelen, GFP_KERNEL); + if (!ls) + goto out; + memset(ls, 0, sizeof(struct dlm_ls) + namelen); + memcpy(ls->ls_name, name, namelen); + ls->ls_namelen = namelen; + ls->ls_exflags = flags; + ls->ls_lvblen = lvblen; + ls->ls_count = 0; + ls->ls_flags = 0; + + size = dlm_config.rsbtbl_size; + ls->ls_rsbtbl_size = size; + + ls->ls_rsbtbl = kmalloc(sizeof(struct dlm_rsbtable) * size, GFP_KERNEL); + if (!ls->ls_rsbtbl) + goto out_lsfree; + for (i = 0; i < size; i++) { + INIT_LIST_HEAD(&ls->ls_rsbtbl[i].list); + INIT_LIST_HEAD(&ls->ls_rsbtbl[i].toss); + rwlock_init(&ls->ls_rsbtbl[i].lock); + } + + size = dlm_config.lkbtbl_size; + ls->ls_lkbtbl_size = size; + + ls->ls_lkbtbl = kmalloc(sizeof(struct dlm_lkbtable) * size, GFP_KERNEL); + if (!ls->ls_lkbtbl) + goto out_rsbfree; + for (i = 0; i < size; i++) { + INIT_LIST_HEAD(&ls->ls_lkbtbl[i].list); + rwlock_init(&ls->ls_lkbtbl[i].lock); + ls->ls_lkbtbl[i].counter = 1; + } + + size = dlm_config.dirtbl_size; + ls->ls_dirtbl_size = size; + + ls->ls_dirtbl = kmalloc(sizeof(struct dlm_dirtable) * size, GFP_KERNEL); + if (!ls->ls_dirtbl) + goto out_lkbfree; + for (i = 0; i < size; i++) { + INIT_LIST_HEAD(&ls->ls_dirtbl[i].list); + rwlock_init(&ls->ls_dirtbl[i].lock); + } + + INIT_LIST_HEAD(&ls->ls_waiters); + init_MUTEX(&ls->ls_waiters_sem); + + INIT_LIST_HEAD(&ls->ls_nodes); + INIT_LIST_HEAD(&ls->ls_nodes_gone); + ls->ls_num_nodes = 0; + ls->ls_low_nodeid = 0; + ls->ls_total_weight = 0; + ls->ls_node_array = NULL; + + memset(&ls->ls_stub_rsb, 0, sizeof(struct dlm_rsb)); + ls->ls_stub_rsb.res_ls = ls; + + ls->ls_debug_dentry = NULL; + + init_waitqueue_head(&ls->ls_uevent_wait); + ls->ls_uevent_result = 0; + + ls->ls_recoverd_task = NULL; + init_MUTEX(&ls->ls_recoverd_active); + spin_lock_init(&ls->ls_recover_lock); + ls->ls_recover_status = 0; + ls->ls_recover_seq = 0; + ls->ls_recover_args = NULL; + init_rwsem(&ls->ls_in_recovery); + INIT_LIST_HEAD(&ls->ls_requestqueue); + init_MUTEX(&ls->ls_requestqueue_lock); + + ls->ls_recover_buf = kmalloc(dlm_config.buffer_size, GFP_KERNEL); + if (!ls->ls_recover_buf) + goto out_dirfree; + + INIT_LIST_HEAD(&ls->ls_recover_list); + spin_lock_init(&ls->ls_recover_list_lock); + ls->ls_recover_list_count = 0; + init_waitqueue_head(&ls->ls_wait_general); + INIT_LIST_HEAD(&ls->ls_root_list); + init_rwsem(&ls->ls_root_sem); + + down_write(&ls->ls_in_recovery); + + error = dlm_recoverd_start(ls); + if (error) { + log_error(ls, "can't start dlm_recoverd %d", error); + goto out_rcomfree; + } + + spin_lock(&lslist_lock); + list_add(&ls->ls_list, &lslist); + spin_unlock(&lslist_lock); + + dlm_create_debug_file(ls); + + error = kobject_setup(ls); + if (error) + goto out_del; + + error = kobject_register(&ls->ls_kobj); + if (error) + goto out_del; + + error = do_uevent(ls, 1); + if (error) + goto out_unreg; + + *lockspace = ls; + return 0; + + out_unreg: + kobject_unregister(&ls->ls_kobj); + out_del: + dlm_delete_debug_file(ls); + spin_lock(&lslist_lock); + list_del(&ls->ls_list); + spin_unlock(&lslist_lock); + dlm_recoverd_stop(ls); + out_rcomfree: + kfree(ls->ls_recover_buf); + out_dirfree: + kfree(ls->ls_dirtbl); + out_lkbfree: + kfree(ls->ls_lkbtbl); + out_rsbfree: + kfree(ls->ls_rsbtbl); + out_lsfree: + kfree(ls); + out: + module_put(THIS_MODULE); + return error; +} + +int dlm_new_lockspace(char *name, int namelen, void **lockspace, + uint32_t flags, int lvblen) +{ + int error = 0; + + down(&ls_lock); + if (!ls_count) + error = threads_start(); + if (error) + goto out; + + error = new_lockspace(name, namelen, lockspace, flags, lvblen); + if (!error) + ls_count++; + out: + up(&ls_lock); + return error; +} + +/* Return 1 if the lockspace still has active remote locks, + * 2 if the lockspace still has active local locks. + */ +static int lockspace_busy(struct dlm_ls *ls) +{ + int i, lkb_found = 0; + struct dlm_lkb *lkb; + + /* NOTE: We check the lockidtbl here rather than the resource table. + This is because there may be LKBs queued as ASTs that have been + unlinked from their RSBs and are pending deletion once the AST has + been delivered */ + + for (i = 0; i < ls->ls_lkbtbl_size; i++) { + read_lock(&ls->ls_lkbtbl[i].lock); + if (!list_empty(&ls->ls_lkbtbl[i].list)) { + lkb_found = 1; + list_for_each_entry(lkb, &ls->ls_lkbtbl[i].list, + lkb_idtbl_list) { + if (!lkb->lkb_nodeid) { + read_unlock(&ls->ls_lkbtbl[i].lock); + return 2; + } + } + } + read_unlock(&ls->ls_lkbtbl[i].lock); + } + return lkb_found; +} + +static int release_lockspace(struct dlm_ls *ls, int force) +{ + struct dlm_lkb *lkb; + struct dlm_rsb *rsb; + struct list_head *head; + int i; + int busy = lockspace_busy(ls); + + if (busy > force) + return -EBUSY; + + if (force < 3) + do_uevent(ls, 0); + + dlm_recoverd_stop(ls); + + remove_lockspace(ls); + + dlm_delete_debug_file(ls); + + dlm_astd_suspend(); + + kfree(ls->ls_recover_buf); + + /* + * Free direntry structs. + */ + + dlm_dir_clear(ls); + kfree(ls->ls_dirtbl); + + /* + * Free all lkb's on lkbtbl[] lists. + */ + + for (i = 0; i < ls->ls_lkbtbl_size; i++) { + head = &ls->ls_lkbtbl[i].list; + while (!list_empty(head)) { + lkb = list_entry(head->next, struct dlm_lkb, + lkb_idtbl_list); + + list_del(&lkb->lkb_idtbl_list); + + dlm_del_ast(lkb); + + if (lkb->lkb_lvbptr && lkb->lkb_flags & DLM_IFL_MSTCPY) + free_lvb(lkb->lkb_lvbptr); + + free_lkb(lkb); + } + } + dlm_astd_resume(); + + kfree(ls->ls_lkbtbl); + + /* + * Free all rsb's on rsbtbl[] lists + */ + + for (i = 0; i < ls->ls_rsbtbl_size; i++) { + head = &ls->ls_rsbtbl[i].list; + while (!list_empty(head)) { + rsb = list_entry(head->next, struct dlm_rsb, + res_hashchain); + + list_del(&rsb->res_hashchain); + free_rsb(rsb); + } + + head = &ls->ls_rsbtbl[i].toss; + while (!list_empty(head)) { + rsb = list_entry(head->next, struct dlm_rsb, + res_hashchain); + list_del(&rsb->res_hashchain); + free_rsb(rsb); + } + } + + kfree(ls->ls_rsbtbl); + + /* + * Free structures on any other lists + */ + + kfree(ls->ls_recover_args); + dlm_clear_free_entries(ls); + dlm_clear_members(ls); + dlm_clear_members_gone(ls); + kfree(ls->ls_node_array); + kobject_unregister(&ls->ls_kobj); + kfree(ls); + + down(&ls_lock); + ls_count--; + if (!ls_count) + threads_stop(); + up(&ls_lock); + + module_put(THIS_MODULE); + return 0; +} + +/* + * Called when a system has released all its locks and is not going to use the + * lockspace any longer. We free everything we're managing for this lockspace. + * Remaining nodes will go through the recovery process as if we'd died. The + * lockspace must continue to function as usual, participating in recoveries, + * until this returns. + * + * Force has 4 possible values: + * 0 - don't destroy locksapce if it has any LKBs + * 1 - destroy lockspace if it has remote LKBs but not if it has local LKBs + * 2 - destroy lockspace regardless of LKBs + * 3 - destroy lockspace as part of a forced shutdown + */ + +int dlm_release_lockspace(void *lockspace, int force) +{ + struct dlm_ls *ls; + + ls = dlm_find_lockspace_local(lockspace); + if (!ls) + return -EINVAL; + dlm_put_lockspace(ls); + return release_lockspace(ls, force); +} + diff --git a/fs/dlm/lockspace.h b/fs/dlm/lockspace.h new file mode 100644 index 000000000000..17bd3ba863a9 --- /dev/null +++ b/fs/dlm/lockspace.h @@ -0,0 +1,24 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __LOCKSPACE_DOT_H__ +#define __LOCKSPACE_DOT_H__ + +int dlm_lockspace_init(void); +void dlm_lockspace_exit(void); +struct dlm_ls *dlm_find_lockspace_global(uint32_t id); +struct dlm_ls *dlm_find_lockspace_local(void *id); +void dlm_put_lockspace(struct dlm_ls *ls); + +#endif /* __LOCKSPACE_DOT_H__ */ + diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c new file mode 100644 index 000000000000..09b0124f7fc4 --- /dev/null +++ b/fs/dlm/lowcomms.c @@ -0,0 +1,1218 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +/* + * lowcomms.c + * + * This is the "low-level" comms layer. + * + * It is responsible for sending/receiving messages + * from other nodes in the cluster. + * + * Cluster nodes are referred to by their nodeids. nodeids are + * simply 32 bit numbers to the locking module - if they need to + * be expanded for the cluster infrastructure then that is it's + * responsibility. It is this layer's + * responsibility to resolve these into IP address or + * whatever it needs for inter-node communication. + * + * The comms level is two kernel threads that deal mainly with + * the receiving of messages from other nodes and passing them + * up to the mid-level comms layer (which understands the + * message format) for execution by the locking core, and + * a send thread which does all the setting up of connections + * to remote nodes and the sending of data. Threads are not allowed + * to send their own data because it may cause them to wait in times + * of high load. Also, this way, the sending thread can collect together + * messages bound for one node and send them in one block. + * + * I don't see any problem with the recv thread executing the locking + * code on behalf of remote processes as the locking code is + * short, efficient and never (well, hardly ever) waits. + * + */ + +#include <asm/ioctls.h> +#include <net/sock.h> +#include <net/tcp.h> +#include <net/sctp/user.h> +#include <linux/pagemap.h> +#include <linux/socket.h> +#include <linux/idr.h> + +#include "dlm_internal.h" +#include "lowcomms.h" +#include "config.h" +#include "midcomms.h" + +static struct sockaddr_storage *local_addr[DLM_MAX_ADDR_COUNT]; +static int local_count; +static int local_nodeid; + +/* One of these per connected node */ + +#define NI_INIT_PENDING 1 +#define NI_WRITE_PENDING 2 + +struct nodeinfo { + spinlock_t lock; + sctp_assoc_t assoc_id; + unsigned long flags; + struct list_head write_list; /* nodes with pending writes */ + struct list_head writequeue; /* outgoing writequeue_entries */ + spinlock_t writequeue_lock; + int nodeid; +}; + +static DEFINE_IDR(nodeinfo_idr); +static struct rw_semaphore nodeinfo_lock; +static int max_nodeid; + +struct cbuf { + unsigned base; + unsigned len; + unsigned mask; +}; + +/* Just the one of these, now. But this struct keeps + the connection-specific variables together */ + +#define CF_READ_PENDING 1 + +struct connection { + struct socket *sock; + unsigned long flags; + struct page *rx_page; + atomic_t waiting_requests; + struct cbuf cb; + int eagain_flag; +}; + +/* An entry waiting to be sent */ + +struct writequeue_entry { + struct list_head list; + struct page *page; + int offset; + int len; + int end; + int users; + struct nodeinfo *ni; +}; + +#define CBUF_ADD(cb, n) do { (cb)->len += n; } while(0) +#define CBUF_EMPTY(cb) ((cb)->len == 0) +#define CBUF_MAY_ADD(cb, n) (((cb)->len + (n)) < ((cb)->mask + 1)) +#define CBUF_DATA(cb) (((cb)->base + (cb)->len) & (cb)->mask) + +#define CBUF_INIT(cb, size) \ +do { \ + (cb)->base = (cb)->len = 0; \ + (cb)->mask = ((size)-1); \ +} while(0) + +#define CBUF_EAT(cb, n) \ +do { \ + (cb)->len -= (n); \ + (cb)->base += (n); \ + (cb)->base &= (cb)->mask; \ +} while(0) + + +/* List of nodes which have writes pending */ +static struct list_head write_nodes; +static spinlock_t write_nodes_lock; + +/* Maximum number of incoming messages to process before + * doing a schedule() + */ +#define MAX_RX_MSG_COUNT 25 + +/* Manage daemons */ +static struct task_struct *recv_task; +static struct task_struct *send_task; +static wait_queue_head_t lowcomms_recv_wait; +static atomic_t accepting; + +/* The SCTP connection */ +static struct connection sctp_con; + + +static int nodeid_to_addr(int nodeid, struct sockaddr *retaddr) +{ + struct sockaddr_storage addr; + int error; + + if (!local_count) + return -1; + + error = dlm_nodeid_to_addr(nodeid, &addr); + if (error) + return error; + + if (local_addr[0]->ss_family == AF_INET) { + struct sockaddr_in *in4 = (struct sockaddr_in *) &addr; + struct sockaddr_in *ret4 = (struct sockaddr_in *) retaddr; + ret4->sin_addr.s_addr = in4->sin_addr.s_addr; + } else { + struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) &addr; + struct sockaddr_in6 *ret6 = (struct sockaddr_in6 *) retaddr; + memcpy(&ret6->sin6_addr, &in6->sin6_addr, + sizeof(in6->sin6_addr)); + } + + return 0; +} + +static struct nodeinfo *nodeid2nodeinfo(int nodeid, int alloc) +{ + struct nodeinfo *ni; + int r; + int n; + + down_read(&nodeinfo_lock); + ni = idr_find(&nodeinfo_idr, nodeid); + up_read(&nodeinfo_lock); + + if (!ni && alloc) { + down_write(&nodeinfo_lock); + + ni = idr_find(&nodeinfo_idr, nodeid); + if (ni) + goto out_up; + + r = idr_pre_get(&nodeinfo_idr, alloc); + if (!r) + goto out_up; + + ni = kmalloc(sizeof(struct nodeinfo), alloc); + if (!ni) + goto out_up; + + r = idr_get_new_above(&nodeinfo_idr, ni, nodeid, &n); + if (r) { + kfree(ni); + ni = NULL; + goto out_up; + } + if (n != nodeid) { + idr_remove(&nodeinfo_idr, n); + kfree(ni); + ni = NULL; + goto out_up; + } + memset(ni, 0, sizeof(struct nodeinfo)); + spin_lock_init(&ni->lock); + INIT_LIST_HEAD(&ni->writequeue); + spin_lock_init(&ni->writequeue_lock); + ni->nodeid = nodeid; + + if (nodeid > max_nodeid) + max_nodeid = nodeid; + out_up: + up_write(&nodeinfo_lock); + } + + return ni; +} + +/* Don't call this too often... */ +static struct nodeinfo *assoc2nodeinfo(sctp_assoc_t assoc) +{ + int i; + struct nodeinfo *ni; + + for (i=1; i<=max_nodeid; i++) { + ni = nodeid2nodeinfo(i, 0); + if (ni && ni->assoc_id == assoc) + return ni; + } + return NULL; +} + +/* Data or notification available on socket */ +static void lowcomms_data_ready(struct sock *sk, int count_unused) +{ + atomic_inc(&sctp_con.waiting_requests); + if (test_and_set_bit(CF_READ_PENDING, &sctp_con.flags)) + return; + + wake_up_interruptible(&lowcomms_recv_wait); +} + + +/* Add the port number to an IP6 or 4 sockaddr and return the address length. + Also padd out the struct with zeros to make comparisons meaningful */ + +static void make_sockaddr(struct sockaddr_storage *saddr, uint16_t port, + int *addr_len) +{ + struct sockaddr_in *local4_addr; + struct sockaddr_in6 *local6_addr; + + if (!local_count) + return; + + if (!port) { + if (local_addr[0]->ss_family == AF_INET) { + local4_addr = (struct sockaddr_in *)local_addr[0]; + port = be16_to_cpu(local4_addr->sin_port); + } else { + local6_addr = (struct sockaddr_in6 *)local_addr[0]; + port = be16_to_cpu(local6_addr->sin6_port); + } + } + + saddr->ss_family = local_addr[0]->ss_family; + if (local_addr[0]->ss_family == AF_INET) { + struct sockaddr_in *in4_addr = (struct sockaddr_in *)saddr; + in4_addr->sin_port = cpu_to_be16(port); + memset(&in4_addr->sin_zero, 0, sizeof(in4_addr->sin_zero)); + memset(in4_addr+1, 0, sizeof(struct sockaddr_storage) - + sizeof(struct sockaddr_in)); + *addr_len = sizeof(struct sockaddr_in); + } else { + struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)saddr; + in6_addr->sin6_port = cpu_to_be16(port); + memset(in6_addr+1, 0, sizeof(struct sockaddr_storage) - + sizeof(struct sockaddr_in6)); + *addr_len = sizeof(struct sockaddr_in6); + } +} + +/* Close the connection and tidy up */ +static void close_connection(void) +{ + if (sctp_con.sock) { + sock_release(sctp_con.sock); + sctp_con.sock = NULL; + } + + if (sctp_con.rx_page) { + __free_page(sctp_con.rx_page); + sctp_con.rx_page = NULL; + } +} + +/* We only send shutdown messages to nodes that are not part of the cluster */ +static void send_shutdown(sctp_assoc_t associd) +{ + static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; + struct msghdr outmessage; + struct cmsghdr *cmsg; + struct sctp_sndrcvinfo *sinfo; + int ret; + + outmessage.msg_name = NULL; + outmessage.msg_namelen = 0; + outmessage.msg_control = outcmsg; + outmessage.msg_controllen = sizeof(outcmsg); + outmessage.msg_flags = MSG_EOR; + + cmsg = CMSG_FIRSTHDR(&outmessage); + cmsg->cmsg_level = IPPROTO_SCTP; + cmsg->cmsg_type = SCTP_SNDRCV; + cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); + outmessage.msg_controllen = cmsg->cmsg_len; + sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); + memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); + + sinfo->sinfo_flags |= MSG_EOF; + sinfo->sinfo_assoc_id = associd; + + ret = kernel_sendmsg(sctp_con.sock, &outmessage, NULL, 0, 0); + + if (ret != 0) + log_print("send EOF to node failed: %d", ret); +} + + +/* INIT failed but we don't know which node... + restart INIT on all pending nodes */ +static void init_failed(void) +{ + int i; + struct nodeinfo *ni; + + for (i=1; i<=max_nodeid; i++) { + ni = nodeid2nodeinfo(i, 0); + if (!ni) + continue; + + if (test_and_clear_bit(NI_INIT_PENDING, &ni->flags)) { + ni->assoc_id = 0; + if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { + spin_lock_bh(&write_nodes_lock); + list_add_tail(&ni->write_list, &write_nodes); + spin_unlock_bh(&write_nodes_lock); + } + } + } + wake_up_process(send_task); +} + +/* Something happened to an association */ +static void process_sctp_notification(struct msghdr *msg, char *buf) +{ + union sctp_notification *sn = (union sctp_notification *)buf; + + if (sn->sn_header.sn_type == SCTP_ASSOC_CHANGE) { + switch (sn->sn_assoc_change.sac_state) { + + case SCTP_COMM_UP: + case SCTP_RESTART: + { + /* Check that the new node is in the lockspace */ + struct sctp_prim prim; + mm_segment_t fs; + int nodeid; + int prim_len, ret; + int addr_len; + struct nodeinfo *ni; + + /* This seems to happen when we received a connection + * too early... or something... anyway, it happens but + * we always seem to get a real message too, see + * receive_from_sock */ + + if ((int)sn->sn_assoc_change.sac_assoc_id <= 0) { + log_print("COMM_UP for invalid assoc ID %d", + (int)sn->sn_assoc_change.sac_assoc_id); + init_failed(); + return; + } + memset(&prim, 0, sizeof(struct sctp_prim)); + prim_len = sizeof(struct sctp_prim); + prim.ssp_assoc_id = sn->sn_assoc_change.sac_assoc_id; + + fs = get_fs(); + set_fs(get_ds()); + ret = sctp_con.sock->ops->getsockopt(sctp_con.sock, + IPPROTO_SCTP, SCTP_PRIMARY_ADDR, + (char*)&prim, &prim_len); + set_fs(fs); + if (ret < 0) { + struct nodeinfo *ni; + + log_print("getsockopt/sctp_primary_addr on " + "new assoc %d failed : %d", + (int)sn->sn_assoc_change.sac_assoc_id, ret); + + /* Retry INIT later */ + ni = assoc2nodeinfo(sn->sn_assoc_change.sac_assoc_id); + if (ni) + clear_bit(NI_INIT_PENDING, &ni->flags); + return; + } + make_sockaddr(&prim.ssp_addr, 0, &addr_len); + if (dlm_addr_to_nodeid(&prim.ssp_addr, &nodeid)) { + log_print("reject connect from unknown addr"); + send_shutdown(prim.ssp_assoc_id); + return; + } + + ni = nodeid2nodeinfo(nodeid, GFP_KERNEL); + if (!ni) + return; + + /* Save the assoc ID */ + spin_lock(&ni->lock); + ni->assoc_id = sn->sn_assoc_change.sac_assoc_id; + spin_unlock(&ni->lock); + + log_print("got new/restarted association %d nodeid %d", + (int)sn->sn_assoc_change.sac_assoc_id, nodeid); + + /* Send any pending writes */ + clear_bit(NI_INIT_PENDING, &ni->flags); + if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { + spin_lock_bh(&write_nodes_lock); + list_add_tail(&ni->write_list, &write_nodes); + spin_unlock_bh(&write_nodes_lock); + } + wake_up_process(send_task); + } + break; + + case SCTP_COMM_LOST: + case SCTP_SHUTDOWN_COMP: + { + struct nodeinfo *ni; + + ni = assoc2nodeinfo(sn->sn_assoc_change.sac_assoc_id); + if (ni) { + spin_lock(&ni->lock); + ni->assoc_id = 0; + spin_unlock(&ni->lock); + } + } + break; + + /* We don't know which INIT failed, so clear the PENDING flags + * on them all. if assoc_id is zero then it will then try + * again */ + + case SCTP_CANT_STR_ASSOC: + { + log_print("Can't start SCTP association - retrying"); + init_failed(); + } + break; + + default: + log_print("unexpected SCTP assoc change id=%d state=%d", + (int)sn->sn_assoc_change.sac_assoc_id, + sn->sn_assoc_change.sac_state); + } + } +} + +/* Data received from remote end */ +static int receive_from_sock(void) +{ + int ret = 0; + struct msghdr msg; + struct kvec iov[2]; + unsigned len; + int r; + struct sctp_sndrcvinfo *sinfo; + struct cmsghdr *cmsg; + struct nodeinfo *ni; + + /* These two are marginally too big for stack allocation, but this + * function is (currently) only called by dlm_recvd so static should be + * OK. + */ + static struct sockaddr_storage msgname; + static char incmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; + + if (sctp_con.sock == NULL) + goto out; + + if (sctp_con.rx_page == NULL) { + /* + * This doesn't need to be atomic, but I think it should + * improve performance if it is. + */ + sctp_con.rx_page = alloc_page(GFP_ATOMIC); + if (sctp_con.rx_page == NULL) + goto out_resched; + CBUF_INIT(&sctp_con.cb, PAGE_CACHE_SIZE); + } + + memset(&incmsg, 0, sizeof(incmsg)); + memset(&msgname, 0, sizeof(msgname)); + + memset(incmsg, 0, sizeof(incmsg)); + msg.msg_name = &msgname; + msg.msg_namelen = sizeof(msgname); + msg.msg_flags = 0; + msg.msg_control = incmsg; + msg.msg_controllen = sizeof(incmsg); + + /* I don't see why this circular buffer stuff is necessary for SCTP + * which is a packet-based protocol, but the whole thing breaks under + * load without it! The overhead is minimal (and is in the TCP lowcomms + * anyway, of course) so I'll leave it in until I can figure out what's + * really happening. + */ + + /* + * iov[0] is the bit of the circular buffer between the current end + * point (cb.base + cb.len) and the end of the buffer. + */ + iov[0].iov_len = sctp_con.cb.base - CBUF_DATA(&sctp_con.cb); + iov[0].iov_base = page_address(sctp_con.rx_page) + + CBUF_DATA(&sctp_con.cb); + iov[1].iov_len = 0; + + /* + * iov[1] is the bit of the circular buffer between the start of the + * buffer and the start of the currently used section (cb.base) + */ + if (CBUF_DATA(&sctp_con.cb) >= sctp_con.cb.base) { + iov[0].iov_len = PAGE_CACHE_SIZE - CBUF_DATA(&sctp_con.cb); + iov[1].iov_len = sctp_con.cb.base; + iov[1].iov_base = page_address(sctp_con.rx_page); + msg.msg_iovlen = 2; + } + len = iov[0].iov_len + iov[1].iov_len; + + r = ret = kernel_recvmsg(sctp_con.sock, &msg, iov, 1, len, + MSG_NOSIGNAL | MSG_DONTWAIT); + if (ret <= 0) + goto out_close; + + msg.msg_control = incmsg; + msg.msg_controllen = sizeof(incmsg); + cmsg = CMSG_FIRSTHDR(&msg); + sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); + + if (msg.msg_flags & MSG_NOTIFICATION) { + process_sctp_notification(&msg, page_address(sctp_con.rx_page)); + return 0; + } + + /* Is this a new association ? */ + ni = nodeid2nodeinfo(le32_to_cpu(sinfo->sinfo_ppid), GFP_KERNEL); + if (ni) { + ni->assoc_id = sinfo->sinfo_assoc_id; + if (test_and_clear_bit(NI_INIT_PENDING, &ni->flags)) { + + if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { + spin_lock_bh(&write_nodes_lock); + list_add_tail(&ni->write_list, &write_nodes); + spin_unlock_bh(&write_nodes_lock); + } + wake_up_process(send_task); + } + } + + /* INIT sends a message with length of 1 - ignore it */ + if (r == 1) + return 0; + + CBUF_ADD(&sctp_con.cb, ret); + ret = dlm_process_incoming_buffer(cpu_to_le32(sinfo->sinfo_ppid), + page_address(sctp_con.rx_page), + sctp_con.cb.base, sctp_con.cb.len, + PAGE_CACHE_SIZE); + if (ret < 0) + goto out_close; + CBUF_EAT(&sctp_con.cb, ret); + + out: + ret = 0; + goto out_ret; + + out_resched: + lowcomms_data_ready(sctp_con.sock->sk, 0); + ret = 0; + schedule(); + goto out_ret; + + out_close: + if (ret != -EAGAIN) + log_print("error reading from sctp socket: %d", ret); + out_ret: + return ret; +} + +/* Bind to an IP address. SCTP allows multiple address so it can do multi-homing */ +static int add_bind_addr(struct sockaddr_storage *addr, int addr_len, int num) +{ + mm_segment_t fs; + int result = 0; + + fs = get_fs(); + set_fs(get_ds()); + if (num == 1) + result = sctp_con.sock->ops->bind(sctp_con.sock, + (struct sockaddr *) addr, addr_len); + else + result = sctp_con.sock->ops->setsockopt(sctp_con.sock, SOL_SCTP, + SCTP_SOCKOPT_BINDX_ADD, (char *)addr, addr_len); + set_fs(fs); + + if (result < 0) + log_print("Can't bind to port %d addr number %d", + dlm_config.tcp_port, num); + + return result; +} + +static void init_local(void) +{ + struct sockaddr_storage sas, *addr; + int i; + + local_nodeid = dlm_our_nodeid(); + + for (i = 0; i < DLM_MAX_ADDR_COUNT - 1; i++) { + if (dlm_our_addr(&sas, i)) + break; + + addr = kmalloc(sizeof(*addr), GFP_KERNEL); + if (!addr) + break; + memcpy(addr, &sas, sizeof(*addr)); + local_addr[local_count++] = addr; + } +} + +/* Initialise SCTP socket and bind to all interfaces */ +static int init_sock(void) +{ + mm_segment_t fs; + struct socket *sock = NULL; + struct sockaddr_storage localaddr; + struct sctp_event_subscribe subscribe; + int result = -EINVAL, num = 1, i, addr_len; + + if (!local_count) { + init_local(); + if (!local_count) { + log_print("no local IP address has been set"); + goto out; + } + } + + result = sock_create_kern(local_addr[0]->ss_family, SOCK_SEQPACKET, + IPPROTO_SCTP, &sock); + if (result < 0) { + log_print("Can't create comms socket, check SCTP is loaded"); + goto out; + } + + /* Listen for events */ + memset(&subscribe, 0, sizeof(subscribe)); + subscribe.sctp_data_io_event = 1; + subscribe.sctp_association_event = 1; + subscribe.sctp_send_failure_event = 1; + subscribe.sctp_shutdown_event = 1; + subscribe.sctp_partial_delivery_event = 1; + + fs = get_fs(); + set_fs(get_ds()); + result = sock->ops->setsockopt(sock, SOL_SCTP, SCTP_EVENTS, + (char *)&subscribe, sizeof(subscribe)); + set_fs(fs); + + if (result < 0) { + log_print("Failed to set SCTP_EVENTS on socket: result=%d", + result); + goto create_delsock; + } + + /* Init con struct */ + sock->sk->sk_user_data = &sctp_con; + sctp_con.sock = sock; + sctp_con.sock->sk->sk_data_ready = lowcomms_data_ready; + + /* Bind to all interfaces. */ + for (i = 0; i < local_count; i++) { + memcpy(&localaddr, local_addr[i], sizeof(localaddr)); + make_sockaddr(&localaddr, dlm_config.tcp_port, &addr_len); + + result = add_bind_addr(&localaddr, addr_len, num); + if (result) + goto create_delsock; + ++num; + } + + result = sock->ops->listen(sock, 5); + if (result < 0) { + log_print("Can't set socket listening"); + goto create_delsock; + } + + return 0; + + create_delsock: + sock_release(sock); + sctp_con.sock = NULL; + out: + return result; +} + + +static struct writequeue_entry *new_writequeue_entry(int allocation) +{ + struct writequeue_entry *entry; + + entry = kmalloc(sizeof(struct writequeue_entry), allocation); + if (!entry) + return NULL; + + entry->page = alloc_page(allocation); + if (!entry->page) { + kfree(entry); + return NULL; + } + + entry->offset = 0; + entry->len = 0; + entry->end = 0; + entry->users = 0; + + return entry; +} + +void *dlm_lowcomms_get_buffer(int nodeid, int len, int allocation, char **ppc) +{ + struct writequeue_entry *e; + int offset = 0; + int users = 0; + struct nodeinfo *ni; + + if (!atomic_read(&accepting)) + return NULL; + + ni = nodeid2nodeinfo(nodeid, allocation); + if (!ni) + return NULL; + + spin_lock(&ni->writequeue_lock); + e = list_entry(ni->writequeue.prev, struct writequeue_entry, list); + if (((struct list_head *) e == &ni->writequeue) || + (PAGE_CACHE_SIZE - e->end < len)) { + e = NULL; + } else { + offset = e->end; + e->end += len; + users = e->users++; + } + spin_unlock(&ni->writequeue_lock); + + if (e) { + got_one: + if (users == 0) + kmap(e->page); + *ppc = page_address(e->page) + offset; + return e; + } + + e = new_writequeue_entry(allocation); + if (e) { + spin_lock(&ni->writequeue_lock); + offset = e->end; + e->end += len; + e->ni = ni; + users = e->users++; + list_add_tail(&e->list, &ni->writequeue); + spin_unlock(&ni->writequeue_lock); + goto got_one; + } + return NULL; +} + +void dlm_lowcomms_commit_buffer(void *arg) +{ + struct writequeue_entry *e = (struct writequeue_entry *) arg; + int users; + struct nodeinfo *ni = e->ni; + + if (!atomic_read(&accepting)) + return; + + spin_lock(&ni->writequeue_lock); + users = --e->users; + if (users) + goto out; + e->len = e->end - e->offset; + kunmap(e->page); + spin_unlock(&ni->writequeue_lock); + + if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { + spin_lock_bh(&write_nodes_lock); + list_add_tail(&ni->write_list, &write_nodes); + spin_unlock_bh(&write_nodes_lock); + wake_up_process(send_task); + } + return; + + out: + spin_unlock(&ni->writequeue_lock); + return; +} + +static void free_entry(struct writequeue_entry *e) +{ + __free_page(e->page); + kfree(e); +} + +/* Initiate an SCTP association. In theory we could just use sendmsg() on + the first IP address and it should work, but this allows us to set up the + association before sending any valuable data that we can't afford to lose. + It also keeps the send path clean as it can now always use the association ID */ +static void initiate_association(int nodeid) +{ + struct sockaddr_storage rem_addr; + static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; + struct msghdr outmessage; + struct cmsghdr *cmsg; + struct sctp_sndrcvinfo *sinfo; + int ret; + int addrlen; + char buf[1]; + struct kvec iov[1]; + struct nodeinfo *ni; + + log_print("Initiating association with node %d", nodeid); + + ni = nodeid2nodeinfo(nodeid, GFP_KERNEL); + if (!ni) + return; + + if (nodeid_to_addr(nodeid, (struct sockaddr *)&rem_addr)) { + log_print("no address for nodeid %d", nodeid); + return; + } + + make_sockaddr(&rem_addr, dlm_config.tcp_port, &addrlen); + + outmessage.msg_name = &rem_addr; + outmessage.msg_namelen = addrlen; + outmessage.msg_control = outcmsg; + outmessage.msg_controllen = sizeof(outcmsg); + outmessage.msg_flags = MSG_EOR; + + iov[0].iov_base = buf; + iov[0].iov_len = 1; + + /* Real INIT messages seem to cause trouble. Just send a 1 byte message + we can afford to lose */ + cmsg = CMSG_FIRSTHDR(&outmessage); + cmsg->cmsg_level = IPPROTO_SCTP; + cmsg->cmsg_type = SCTP_SNDRCV; + cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); + sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); + memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); + sinfo->sinfo_ppid = cpu_to_le32(local_nodeid); + + outmessage.msg_controllen = cmsg->cmsg_len; + ret = kernel_sendmsg(sctp_con.sock, &outmessage, iov, 1, 1); + if (ret < 0) { + log_print("send INIT to node failed: %d", ret); + /* Try again later */ + clear_bit(NI_INIT_PENDING, &ni->flags); + } +} + +/* Send a message */ +static int send_to_sock(struct nodeinfo *ni) +{ + int ret = 0; + struct writequeue_entry *e; + int len, offset; + struct msghdr outmsg; + static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; + struct cmsghdr *cmsg; + struct sctp_sndrcvinfo *sinfo; + struct kvec iov; + + /* See if we need to init an association before we start + sending precious messages */ + spin_lock(&ni->lock); + if (!ni->assoc_id && !test_and_set_bit(NI_INIT_PENDING, &ni->flags)) { + spin_unlock(&ni->lock); + initiate_association(ni->nodeid); + return 0; + } + spin_unlock(&ni->lock); + + outmsg.msg_name = NULL; /* We use assoc_id */ + outmsg.msg_namelen = 0; + outmsg.msg_control = outcmsg; + outmsg.msg_controllen = sizeof(outcmsg); + outmsg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL | MSG_EOR; + + cmsg = CMSG_FIRSTHDR(&outmsg); + cmsg->cmsg_level = IPPROTO_SCTP; + cmsg->cmsg_type = SCTP_SNDRCV; + cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); + sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); + memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); + sinfo->sinfo_ppid = cpu_to_le32(local_nodeid); + sinfo->sinfo_assoc_id = ni->assoc_id; + outmsg.msg_controllen = cmsg->cmsg_len; + + spin_lock(&ni->writequeue_lock); + for (;;) { + if (list_empty(&ni->writequeue)) + break; + e = list_entry(ni->writequeue.next, struct writequeue_entry, + list); + kmap(e->page); + len = e->len; + offset = e->offset; + BUG_ON(len == 0 && e->users == 0); + spin_unlock(&ni->writequeue_lock); + + ret = 0; + if (len) { + iov.iov_base = page_address(e->page)+offset; + iov.iov_len = len; + + ret = kernel_sendmsg(sctp_con.sock, &outmsg, &iov, 1, + len); + if (ret == -EAGAIN) { + sctp_con.eagain_flag = 1; + goto out; + } else if (ret < 0) + goto send_error; + } else { + /* Don't starve people filling buffers */ + schedule(); + } + + spin_lock(&ni->writequeue_lock); + e->offset += ret; + e->len -= ret; + + if (e->len == 0 && e->users == 0) { + list_del(&e->list); + free_entry(e); + continue; + } + } + spin_unlock(&ni->writequeue_lock); + out: + return ret; + + send_error: + log_print("Error sending to node %d %d", ni->nodeid, ret); + spin_lock(&ni->lock); + if (!test_and_set_bit(NI_INIT_PENDING, &ni->flags)) { + ni->assoc_id = 0; + spin_unlock(&ni->lock); + initiate_association(ni->nodeid); + } else + spin_unlock(&ni->lock); + + return ret; +} + +/* Try to send any messages that are pending */ +static void process_output_queue(void) +{ + struct list_head *list; + struct list_head *temp; + + spin_lock_bh(&write_nodes_lock); + list_for_each_safe(list, temp, &write_nodes) { + struct nodeinfo *ni = + list_entry(list, struct nodeinfo, write_list); + clear_bit(NI_WRITE_PENDING, &ni->flags); + list_del(&ni->write_list); + + spin_unlock_bh(&write_nodes_lock); + + send_to_sock(ni); + spin_lock_bh(&write_nodes_lock); + } + spin_unlock_bh(&write_nodes_lock); +} + +/* Called after we've had -EAGAIN and been woken up */ +static void refill_write_queue(void) +{ + int i; + + for (i=1; i<=max_nodeid; i++) { + struct nodeinfo *ni = nodeid2nodeinfo(i, 0); + + if (ni) { + if (!test_and_set_bit(NI_WRITE_PENDING, &ni->flags)) { + spin_lock_bh(&write_nodes_lock); + list_add_tail(&ni->write_list, &write_nodes); + spin_unlock_bh(&write_nodes_lock); + } + } + } +} + +static void clean_one_writequeue(struct nodeinfo *ni) +{ + struct list_head *list; + struct list_head *temp; + + spin_lock(&ni->writequeue_lock); + list_for_each_safe(list, temp, &ni->writequeue) { + struct writequeue_entry *e = + list_entry(list, struct writequeue_entry, list); + list_del(&e->list); + free_entry(e); + } + spin_unlock(&ni->writequeue_lock); +} + +static void clean_writequeues(void) +{ + int i; + + for (i=1; i<=max_nodeid; i++) { + struct nodeinfo *ni = nodeid2nodeinfo(i, 0); + if (ni) + clean_one_writequeue(ni); + } +} + + +static void dealloc_nodeinfo(void) +{ + int i; + + for (i=1; i<=max_nodeid; i++) { + struct nodeinfo *ni = nodeid2nodeinfo(i, 0); + if (ni) { + idr_remove(&nodeinfo_idr, i); + kfree(ni); + } + } +} + +static int write_list_empty(void) +{ + int status; + + spin_lock_bh(&write_nodes_lock); + status = list_empty(&write_nodes); + spin_unlock_bh(&write_nodes_lock); + + return status; +} + +static int dlm_recvd(void *data) +{ + DECLARE_WAITQUEUE(wait, current); + + while (!kthread_should_stop()) { + int count = 0; + + set_current_state(TASK_INTERRUPTIBLE); + add_wait_queue(&lowcomms_recv_wait, &wait); + if (!test_bit(CF_READ_PENDING, &sctp_con.flags)) + schedule(); + remove_wait_queue(&lowcomms_recv_wait, &wait); + set_current_state(TASK_RUNNING); + + if (test_and_clear_bit(CF_READ_PENDING, &sctp_con.flags)) { + int ret; + + do { + ret = receive_from_sock(); + + /* Don't starve out everyone else */ + if (++count >= MAX_RX_MSG_COUNT) { + schedule(); + count = 0; + } + } while (!kthread_should_stop() && ret >=0); + } + schedule(); + } + + return 0; +} + +static int dlm_sendd(void *data) +{ + DECLARE_WAITQUEUE(wait, current); + + add_wait_queue(sctp_con.sock->sk->sk_sleep, &wait); + + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + if (write_list_empty()) + schedule(); + set_current_state(TASK_RUNNING); + + if (sctp_con.eagain_flag) { + sctp_con.eagain_flag = 0; + refill_write_queue(); + } + process_output_queue(); + } + + remove_wait_queue(sctp_con.sock->sk->sk_sleep, &wait); + + return 0; +} + +static void daemons_stop(void) +{ + kthread_stop(recv_task); + kthread_stop(send_task); +} + +static int daemons_start(void) +{ + struct task_struct *p; + int error; + + p = kthread_run(dlm_recvd, NULL, "dlm_recvd"); + error = IS_ERR(p); + if (error) { + log_print("can't start dlm_recvd %d", error); + return error; + } + recv_task = p; + + p = kthread_run(dlm_sendd, NULL, "dlm_sendd"); + error = IS_ERR(p); + if (error) { + log_print("can't start dlm_sendd %d", error); + kthread_stop(recv_task); + return error; + } + send_task = p; + + return 0; +} + +/* + * This is quite likely to sleep... + */ +int dlm_lowcomms_start(void) +{ + int error; + + spin_lock_init(&write_nodes_lock); + INIT_LIST_HEAD(&write_nodes); + init_rwsem(&nodeinfo_lock); + + error = init_sock(); + if (error) + goto fail_sock; + error = daemons_start(); + if (error) + goto fail_sock; + atomic_set(&accepting, 1); + return 0; + + fail_sock: + close_connection(); + return error; +} + +/* Set all the activity flags to prevent any socket activity. */ + +void dlm_lowcomms_stop(void) +{ + atomic_set(&accepting, 0); + sctp_con.flags = 0x7; + daemons_stop(); + clean_writequeues(); + close_connection(); + dealloc_nodeinfo(); + max_nodeid = 0; +} + +int dlm_lowcomms_init(void) +{ + init_waitqueue_head(&lowcomms_recv_wait); + return 0; +} + +void dlm_lowcomms_exit(void) +{ + int i; + + for (i = 0; i < local_count; i++) + kfree(local_addr[i]); + local_count = 0; + local_nodeid = 0; +} + diff --git a/fs/dlm/lowcomms.h b/fs/dlm/lowcomms.h new file mode 100644 index 000000000000..3af8035ff12f --- /dev/null +++ b/fs/dlm/lowcomms.h @@ -0,0 +1,25 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __LOWCOMMS_DOT_H__ +#define __LOWCOMMS_DOT_H__ + +int dlm_lowcomms_init(void); +void dlm_lowcomms_exit(void); +int dlm_lowcomms_start(void); +void dlm_lowcomms_stop(void); +void *dlm_lowcomms_get_buffer(int nodeid, int len, int allocation, char **ppc); +void dlm_lowcomms_commit_buffer(void *mh); + +#endif /* __LOWCOMMS_DOT_H__ */ + diff --git a/fs/dlm/lvb_table.h b/fs/dlm/lvb_table.h new file mode 100644 index 000000000000..cc3e92f3feef --- /dev/null +++ b/fs/dlm/lvb_table.h @@ -0,0 +1,18 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __LVB_TABLE_DOT_H__ +#define __LVB_TABLE_DOT_H__ + +extern const int dlm_lvb_operations[8][8]; + +#endif diff --git a/fs/dlm/main.c b/fs/dlm/main.c new file mode 100644 index 000000000000..81bf4cb22033 --- /dev/null +++ b/fs/dlm/main.c @@ -0,0 +1,89 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "lock.h" +#include "memory.h" +#include "lowcomms.h" +#include "config.h" + +#ifdef CONFIG_DLM_DEBUG +int dlm_register_debugfs(void); +void dlm_unregister_debugfs(void); +#else +static inline int dlm_register_debugfs(void) { return 0; } +static inline void dlm_unregister_debugfs(void) { } +#endif + +static int __init init_dlm(void) +{ + int error; + + error = dlm_memory_init(); + if (error) + goto out; + + error = dlm_lockspace_init(); + if (error) + goto out_mem; + + error = dlm_config_init(); + if (error) + goto out_lockspace; + + error = dlm_register_debugfs(); + if (error) + goto out_config; + + error = dlm_lowcomms_init(); + if (error) + goto out_debug; + + printk("DLM (built %s %s) installed\n", __DATE__, __TIME__); + + return 0; + + out_debug: + dlm_unregister_debugfs(); + out_config: + dlm_config_exit(); + out_lockspace: + dlm_lockspace_exit(); + out_mem: + dlm_memory_exit(); + out: + return error; +} + +static void __exit exit_dlm(void) +{ + dlm_lowcomms_exit(); + dlm_config_exit(); + dlm_memory_exit(); + dlm_lockspace_exit(); + dlm_unregister_debugfs(); +} + +module_init(init_dlm); +module_exit(exit_dlm); + +MODULE_DESCRIPTION("Distributed Lock Manager"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); + +EXPORT_SYMBOL_GPL(dlm_new_lockspace); +EXPORT_SYMBOL_GPL(dlm_release_lockspace); +EXPORT_SYMBOL_GPL(dlm_lock); +EXPORT_SYMBOL_GPL(dlm_unlock); + diff --git a/fs/dlm/member.c b/fs/dlm/member.c new file mode 100644 index 000000000000..439249b62a57 --- /dev/null +++ b/fs/dlm/member.c @@ -0,0 +1,314 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "member.h" +#include "recoverd.h" +#include "recover.h" +#include "lowcomms.h" +#include "rcom.h" +#include "config.h" + +/* + * Following called by dlm_recoverd thread + */ + +static void add_ordered_member(struct dlm_ls *ls, struct dlm_member *new) +{ + struct dlm_member *memb = NULL; + struct list_head *tmp; + struct list_head *newlist = &new->list; + struct list_head *head = &ls->ls_nodes; + + list_for_each(tmp, head) { + memb = list_entry(tmp, struct dlm_member, list); + if (new->nodeid < memb->nodeid) + break; + } + + if (!memb) + list_add_tail(newlist, head); + else { + /* FIXME: can use list macro here */ + newlist->prev = tmp->prev; + newlist->next = tmp; + tmp->prev->next = newlist; + tmp->prev = newlist; + } +} + +static int dlm_add_member(struct dlm_ls *ls, int nodeid) +{ + struct dlm_member *memb; + int w; + + memb = kmalloc(sizeof(struct dlm_member), GFP_KERNEL); + if (!memb) + return -ENOMEM; + + w = dlm_node_weight(ls->ls_name, nodeid); + if (w < 0) + return w; + + memb->nodeid = nodeid; + memb->weight = w; + add_ordered_member(ls, memb); + ls->ls_num_nodes++; + return 0; +} + +static void dlm_remove_member(struct dlm_ls *ls, struct dlm_member *memb) +{ + list_move(&memb->list, &ls->ls_nodes_gone); + ls->ls_num_nodes--; +} + +static int dlm_is_member(struct dlm_ls *ls, int nodeid) +{ + struct dlm_member *memb; + + list_for_each_entry(memb, &ls->ls_nodes, list) { + if (memb->nodeid == nodeid) + return TRUE; + } + return FALSE; +} + +int dlm_is_removed(struct dlm_ls *ls, int nodeid) +{ + struct dlm_member *memb; + + list_for_each_entry(memb, &ls->ls_nodes_gone, list) { + if (memb->nodeid == nodeid) + return TRUE; + } + return FALSE; +} + +static void clear_memb_list(struct list_head *head) +{ + struct dlm_member *memb; + + while (!list_empty(head)) { + memb = list_entry(head->next, struct dlm_member, list); + list_del(&memb->list); + kfree(memb); + } +} + +void dlm_clear_members(struct dlm_ls *ls) +{ + clear_memb_list(&ls->ls_nodes); + ls->ls_num_nodes = 0; +} + +void dlm_clear_members_gone(struct dlm_ls *ls) +{ + clear_memb_list(&ls->ls_nodes_gone); +} + +static void make_member_array(struct dlm_ls *ls) +{ + struct dlm_member *memb; + int i, w, x = 0, total = 0, all_zero = 0, *array; + + kfree(ls->ls_node_array); + ls->ls_node_array = NULL; + + list_for_each_entry(memb, &ls->ls_nodes, list) { + if (memb->weight) + total += memb->weight; + } + + /* all nodes revert to weight of 1 if all have weight 0 */ + + if (!total) { + total = ls->ls_num_nodes; + all_zero = 1; + } + + ls->ls_total_weight = total; + + array = kmalloc(sizeof(int) * total, GFP_KERNEL); + if (!array) + return; + + list_for_each_entry(memb, &ls->ls_nodes, list) { + if (!all_zero && !memb->weight) + continue; + + if (all_zero) + w = 1; + else + w = memb->weight; + + DLM_ASSERT(x < total, printk("total %d x %d\n", total, x);); + + for (i = 0; i < w; i++) + array[x++] = memb->nodeid; + } + + ls->ls_node_array = array; +} + +/* send a status request to all members just to establish comms connections */ + +static void ping_members(struct dlm_ls *ls) +{ + struct dlm_member *memb; + list_for_each_entry(memb, &ls->ls_nodes, list) + dlm_rcom_status(ls, memb->nodeid); +} + +int dlm_recover_members(struct dlm_ls *ls, struct dlm_recover *rv, int *neg_out) +{ + struct dlm_member *memb, *safe; + int i, error, found, pos = 0, neg = 0, low = -1; + + /* move departed members from ls_nodes to ls_nodes_gone */ + + list_for_each_entry_safe(memb, safe, &ls->ls_nodes, list) { + found = FALSE; + for (i = 0; i < rv->node_count; i++) { + if (memb->nodeid == rv->nodeids[i]) { + found = TRUE; + break; + } + } + + if (!found) { + neg++; + dlm_remove_member(ls, memb); + log_debug(ls, "remove member %d", memb->nodeid); + } + } + + /* add new members to ls_nodes */ + + for (i = 0; i < rv->node_count; i++) { + if (dlm_is_member(ls, rv->nodeids[i])) + continue; + dlm_add_member(ls, rv->nodeids[i]); + pos++; + log_debug(ls, "add member %d", rv->nodeids[i]); + } + + list_for_each_entry(memb, &ls->ls_nodes, list) { + if (low == -1 || memb->nodeid < low) + low = memb->nodeid; + } + ls->ls_low_nodeid = low; + + make_member_array(ls); + dlm_set_recover_status(ls, DLM_RS_NODES); + *neg_out = neg; + + ping_members(ls); + + error = dlm_recover_members_wait(ls); + log_debug(ls, "total members %d", ls->ls_num_nodes); + return error; +} + +/* + * Following called from lockspace.c + */ + +int dlm_ls_stop(struct dlm_ls *ls) +{ + int new; + + /* + * A stop cancels any recovery that's in progress (see RECOVERY_STOP, + * dlm_recovery_stopped()) and prevents any new locks from being + * processed (see RUNNING, dlm_locking_stopped()). + */ + + spin_lock(&ls->ls_recover_lock); + set_bit(LSFL_RECOVERY_STOP, &ls->ls_flags); + new = test_and_clear_bit(LSFL_RUNNING, &ls->ls_flags); + ls->ls_recover_seq++; + spin_unlock(&ls->ls_recover_lock); + + /* + * This in_recovery lock does two things: + * + * 1) Keeps this function from returning until all threads are out + * of locking routines and locking is truely stopped. + * 2) Keeps any new requests from being processed until it's unlocked + * when recovery is complete. + */ + + if (new) + down_write(&ls->ls_in_recovery); + + /* + * The recoverd suspend/resume makes sure that dlm_recoverd (if + * running) has noticed the clearing of RUNNING above and quit + * processing the previous recovery. This will be true for all nodes + * before any nodes start the new recovery. + */ + + dlm_recoverd_suspend(ls); + ls->ls_recover_status = 0; + dlm_recoverd_resume(ls); + return 0; +} + +int dlm_ls_start(struct dlm_ls *ls) +{ + struct dlm_recover *rv = NULL, *rv_old; + int *ids = NULL; + int error, count; + + rv = kmalloc(sizeof(struct dlm_recover), GFP_KERNEL); + if (!rv) + return -ENOMEM; + memset(rv, 0, sizeof(struct dlm_recover)); + + error = count = dlm_nodeid_list(ls->ls_name, &ids); + if (error <= 0) + goto fail; + + spin_lock(&ls->ls_recover_lock); + + /* the lockspace needs to be stopped before it can be started */ + + if (!dlm_locking_stopped(ls)) { + spin_unlock(&ls->ls_recover_lock); + log_error(ls, "start ignored: lockspace running"); + error = -EINVAL; + goto fail; + } + + rv->nodeids = ids; + rv->node_count = count; + rv->seq = ++ls->ls_recover_seq; + rv_old = ls->ls_recover_args; + ls->ls_recover_args = rv; + spin_unlock(&ls->ls_recover_lock); + + if (rv_old) { + kfree(rv_old->nodeids); + kfree(rv_old); + } + + dlm_recoverd_kick(ls); + return 0; + + fail: + kfree(rv); + kfree(ids); + return error; +} + diff --git a/fs/dlm/member.h b/fs/dlm/member.h new file mode 100644 index 000000000000..927c08c19214 --- /dev/null +++ b/fs/dlm/member.h @@ -0,0 +1,24 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __MEMBER_DOT_H__ +#define __MEMBER_DOT_H__ + +int dlm_ls_stop(struct dlm_ls *ls); +int dlm_ls_start(struct dlm_ls *ls); +void dlm_clear_members(struct dlm_ls *ls); +void dlm_clear_members_gone(struct dlm_ls *ls); +int dlm_recover_members(struct dlm_ls *ls, struct dlm_recover *rv,int *neg_out); +int dlm_is_removed(struct dlm_ls *ls, int nodeid); + +#endif /* __MEMBER_DOT_H__ */ + diff --git a/fs/dlm/memory.c b/fs/dlm/memory.c new file mode 100644 index 000000000000..0b9851d0bdb2 --- /dev/null +++ b/fs/dlm/memory.c @@ -0,0 +1,122 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "config.h" +#include "memory.h" + +static kmem_cache_t *lkb_cache; + + +int dlm_memory_init(void) +{ + int ret = 0; + + lkb_cache = kmem_cache_create("dlm_lkb", sizeof(struct dlm_lkb), + __alignof__(struct dlm_lkb), 0, NULL, NULL); + if (!lkb_cache) + ret = -ENOMEM; + return ret; +} + +void dlm_memory_exit(void) +{ + if (lkb_cache) + kmem_cache_destroy(lkb_cache); +} + +char *allocate_lvb(struct dlm_ls *ls) +{ + char *p; + + p = kmalloc(ls->ls_lvblen, GFP_KERNEL); + if (p) + memset(p, 0, ls->ls_lvblen); + return p; +} + +void free_lvb(char *p) +{ + kfree(p); +} + +uint64_t *allocate_range(struct dlm_ls *ls) +{ + int ralen = 4*sizeof(uint64_t); + uint64_t *p; + + p = kmalloc(ralen, GFP_KERNEL); + if (p) + memset(p, 0, ralen); + return p; +} + +void free_range(uint64_t *p) +{ + kfree(p); +} + +/* FIXME: have some minimal space built-in to rsb for the name and + kmalloc a separate name if needed, like dentries are done */ + +struct dlm_rsb *allocate_rsb(struct dlm_ls *ls, int namelen) +{ + struct dlm_rsb *r; + + DLM_ASSERT(namelen <= DLM_RESNAME_MAXLEN,); + + r = kmalloc(sizeof(*r) + namelen, GFP_KERNEL); + if (r) + memset(r, 0, sizeof(*r) + namelen); + return r; +} + +void free_rsb(struct dlm_rsb *r) +{ + if (r->res_lvbptr) + free_lvb(r->res_lvbptr); + kfree(r); +} + +struct dlm_lkb *allocate_lkb(struct dlm_ls *ls) +{ + struct dlm_lkb *lkb; + + lkb = kmem_cache_alloc(lkb_cache, GFP_KERNEL); + if (lkb) + memset(lkb, 0, sizeof(*lkb)); + return lkb; +} + +void free_lkb(struct dlm_lkb *lkb) +{ + kmem_cache_free(lkb_cache, lkb); +} + +struct dlm_direntry *allocate_direntry(struct dlm_ls *ls, int namelen) +{ + struct dlm_direntry *de; + + DLM_ASSERT(namelen <= DLM_RESNAME_MAXLEN,); + + de = kmalloc(sizeof(*de) + namelen, GFP_KERNEL); + if (de) + memset(de, 0, sizeof(*de) + namelen); + return de; +} + +void free_direntry(struct dlm_direntry *de) +{ + kfree(de); +} + diff --git a/fs/dlm/memory.h b/fs/dlm/memory.h new file mode 100644 index 000000000000..7b235132b0b4 --- /dev/null +++ b/fs/dlm/memory.h @@ -0,0 +1,31 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __MEMORY_DOT_H__ +#define __MEMORY_DOT_H__ + +int dlm_memory_init(void); +void dlm_memory_exit(void); +struct dlm_rsb *allocate_rsb(struct dlm_ls *ls, int namelen); +void free_rsb(struct dlm_rsb *r); +struct dlm_lkb *allocate_lkb(struct dlm_ls *ls); +void free_lkb(struct dlm_lkb *l); +struct dlm_direntry *allocate_direntry(struct dlm_ls *ls, int namelen); +void free_direntry(struct dlm_direntry *de); +char *allocate_lvb(struct dlm_ls *ls); +void free_lvb(char *l); +uint64_t *allocate_range(struct dlm_ls *ls); +void free_range(uint64_t *l); + +#endif /* __MEMORY_DOT_H__ */ + diff --git a/fs/dlm/midcomms.c b/fs/dlm/midcomms.c new file mode 100644 index 000000000000..d96f9bbb407c --- /dev/null +++ b/fs/dlm/midcomms.c @@ -0,0 +1,140 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +/* + * midcomms.c + * + * This is the appallingly named "mid-level" comms layer. + * + * Its purpose is to take packets from the "real" comms layer, + * split them up into packets and pass them to the interested + * part of the locking mechanism. + * + * It also takes messages from the locking layer, formats them + * into packets and sends them to the comms layer. + */ + +#include "dlm_internal.h" +#include "lowcomms.h" +#include "config.h" +#include "rcom.h" +#include "lock.h" +#include "midcomms.h" + + +static void copy_from_cb(void *dst, const void *base, unsigned offset, + unsigned len, unsigned limit) +{ + unsigned copy = len; + + if ((copy + offset) > limit) + copy = limit - offset; + memcpy(dst, base + offset, copy); + len -= copy; + if (len) + memcpy(dst + copy, base, len); +} + +/* + * Called from the low-level comms layer to process a buffer of + * commands. + * + * Only complete messages are processed here, any "spare" bytes from + * the end of a buffer are saved and tacked onto the front of the next + * message that comes in. I doubt this will happen very often but we + * need to be able to cope with it and I don't want the task to be waiting + * for packets to come in when there is useful work to be done. + */ + +int dlm_process_incoming_buffer(int nodeid, const void *base, + unsigned offset, unsigned len, unsigned limit) +{ + unsigned char __tmp[DLM_INBUF_LEN]; + struct dlm_header *msg = (struct dlm_header *) __tmp; + int ret = 0; + int err = 0; + uint16_t msglen; + uint32_t lockspace; + + while (len > sizeof(struct dlm_header)) { + + /* Copy just the header to check the total length. The + message may wrap around the end of the buffer back to the + start, so we need to use a temp buffer and copy_from_cb. */ + + copy_from_cb(msg, base, offset, sizeof(struct dlm_header), + limit); + + msglen = le16_to_cpu(msg->h_length); + lockspace = msg->h_lockspace; + + err = -EINVAL; + if (msglen < sizeof(struct dlm_header)) + break; + err = -E2BIG; + if (msglen > dlm_config.buffer_size) { + log_print("message size %d from %d too big, buf len %d", + msglen, nodeid, len); + break; + } + err = 0; + + /* If only part of the full message is contained in this + buffer, then do nothing and wait for lowcomms to call + us again later with more data. We return 0 meaning + we've consumed none of the input buffer. */ + + if (msglen > len) + break; + + /* Allocate a larger temp buffer if the full message won't fit + in the buffer on the stack (which should work for most + ordinary messages). */ + + if (msglen > sizeof(__tmp) && + msg == (struct dlm_header *) __tmp) { + msg = kmalloc(dlm_config.buffer_size, GFP_KERNEL); + if (msg == NULL) + return ret; + } + + copy_from_cb(msg, base, offset, msglen, limit); + + BUG_ON(lockspace != msg->h_lockspace); + + ret += msglen; + offset += msglen; + offset &= (limit - 1); + len -= msglen; + + switch (msg->h_cmd) { + case DLM_MSG: + dlm_receive_message(msg, nodeid, FALSE); + break; + + case DLM_RCOM: + dlm_receive_rcom(msg, nodeid); + break; + + default: + log_print("unknown msg type %x from %u: %u %u %u %u", + msg->h_cmd, nodeid, msglen, len, offset, ret); + } + } + + if (msg != (struct dlm_header *) __tmp) + kfree(msg); + + return err ? err : ret; +} + diff --git a/fs/dlm/midcomms.h b/fs/dlm/midcomms.h new file mode 100644 index 000000000000..95852a5f111d --- /dev/null +++ b/fs/dlm/midcomms.h @@ -0,0 +1,21 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __MIDCOMMS_DOT_H__ +#define __MIDCOMMS_DOT_H__ + +int dlm_process_incoming_buffer(int nodeid, const void *base, unsigned offset, + unsigned len, unsigned limit); + +#endif /* __MIDCOMMS_DOT_H__ */ + diff --git a/fs/dlm/rcom.c b/fs/dlm/rcom.c new file mode 100644 index 000000000000..4c5c08a8860e --- /dev/null +++ b/fs/dlm/rcom.c @@ -0,0 +1,460 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "member.h" +#include "lowcomms.h" +#include "midcomms.h" +#include "rcom.h" +#include "recover.h" +#include "dir.h" +#include "config.h" +#include "memory.h" +#include "lock.h" +#include "util.h" + + +static int rcom_response(struct dlm_ls *ls) +{ + return test_bit(LSFL_RCOM_READY, &ls->ls_flags); +} + +static int create_rcom(struct dlm_ls *ls, int to_nodeid, int type, int len, + struct dlm_rcom **rc_ret, struct dlm_mhandle **mh_ret) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + char *mb; + int mb_len = sizeof(struct dlm_rcom) + len; + + mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb); + if (!mh) { + log_print("create_rcom to %d type %d len %d ENOBUFS", + to_nodeid, type, len); + return -ENOBUFS; + } + memset(mb, 0, mb_len); + + rc = (struct dlm_rcom *) mb; + + rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR); + rc->rc_header.h_lockspace = ls->ls_global_id; + rc->rc_header.h_nodeid = dlm_our_nodeid(); + rc->rc_header.h_length = mb_len; + rc->rc_header.h_cmd = DLM_RCOM; + + rc->rc_type = type; + + *mh_ret = mh; + *rc_ret = rc; + return 0; +} + +static void send_rcom(struct dlm_ls *ls, struct dlm_mhandle *mh, + struct dlm_rcom *rc) +{ + dlm_rcom_out(rc); + dlm_lowcomms_commit_buffer(mh); +} + +/* When replying to a status request, a node also sends back its + configuration values. The requesting node then checks that the remote + node is configured the same way as itself. */ + +static void make_config(struct dlm_ls *ls, struct rcom_config *rf) +{ + rf->rf_lvblen = ls->ls_lvblen; + rf->rf_lsflags = ls->ls_exflags; +} + +static int check_config(struct dlm_ls *ls, struct rcom_config *rf, int nodeid) +{ + if (rf->rf_lvblen != ls->ls_lvblen || + rf->rf_lsflags != ls->ls_exflags) { + log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x", + ls->ls_lvblen, ls->ls_exflags, + nodeid, rf->rf_lvblen, rf->rf_lsflags); + return -EINVAL; + } + return 0; +} + +int dlm_rcom_status(struct dlm_ls *ls, int nodeid) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error = 0; + + memset(ls->ls_recover_buf, 0, dlm_config.buffer_size); + + if (nodeid == dlm_our_nodeid()) { + rc = (struct dlm_rcom *) ls->ls_recover_buf; + rc->rc_result = dlm_recover_status(ls); + goto out; + } + + error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh); + if (error) + goto out; + + send_rcom(ls, mh, rc); + + error = dlm_wait_function(ls, &rcom_response); + clear_bit(LSFL_RCOM_READY, &ls->ls_flags); + if (error) + goto out; + + rc = (struct dlm_rcom *) ls->ls_recover_buf; + + if (rc->rc_result == -ESRCH) { + /* we pretend the remote lockspace exists with 0 status */ + log_debug(ls, "remote node %d not ready", nodeid); + rc->rc_result = 0; + } else + error = check_config(ls, (struct rcom_config *) rc->rc_buf, + nodeid); + /* the caller looks at rc_result for the remote recovery status */ + out: + return error; +} + +static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, nodeid = rc_in->rc_header.h_nodeid; + + error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY, + sizeof(struct rcom_config), &rc, &mh); + if (error) + return; + rc->rc_result = dlm_recover_status(ls); + make_config(ls, (struct rcom_config *) rc->rc_buf); + + send_rcom(ls, mh, rc); +} + +static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length); + set_bit(LSFL_RCOM_READY, &ls->ls_flags); + wake_up(&ls->ls_wait_general); +} + +int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error = 0, len = sizeof(struct dlm_rcom); + + memset(ls->ls_recover_buf, 0, dlm_config.buffer_size); + + if (nodeid == dlm_our_nodeid()) { + dlm_copy_master_names(ls, last_name, last_len, + ls->ls_recover_buf + len, + dlm_config.buffer_size - len, nodeid); + goto out; + } + + error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh); + if (error) + goto out; + memcpy(rc->rc_buf, last_name, last_len); + + send_rcom(ls, mh, rc); + + error = dlm_wait_function(ls, &rcom_response); + clear_bit(LSFL_RCOM_READY, &ls->ls_flags); + out: + return error; +} + +static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, inlen, outlen; + int nodeid = rc_in->rc_header.h_nodeid; + uint32_t status = dlm_recover_status(ls); + + /* + * We can't run dlm_dir_rebuild_send (which uses ls_nodes) while + * dlm_recoverd is running ls_nodes_reconfig (which changes ls_nodes). + * It could only happen in rare cases where we get a late NAMES + * message from a previous instance of recovery. + */ + + if (!(status & DLM_RS_NODES)) { + log_debug(ls, "ignoring RCOM_NAMES from %u", nodeid); + return; + } + + nodeid = rc_in->rc_header.h_nodeid; + inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom); + outlen = dlm_config.buffer_size - sizeof(struct dlm_rcom); + + error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh); + if (error) + return; + + dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen, + nodeid); + send_rcom(ls, mh, rc); +} + +static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length); + set_bit(LSFL_RCOM_READY, &ls->ls_flags); + wake_up(&ls->ls_wait_general); +} + +int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + struct dlm_ls *ls = r->res_ls; + int error; + + error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length, + &rc, &mh); + if (error) + goto out; + memcpy(rc->rc_buf, r->res_name, r->res_length); + rc->rc_id = (unsigned long) r; + + send_rcom(ls, mh, rc); + out: + return error; +} + +static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid; + int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom); + + error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh); + if (error) + return; + + error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid); + if (error) + ret_nodeid = error; + rc->rc_result = ret_nodeid; + rc->rc_id = rc_in->rc_id; + + send_rcom(ls, mh, rc); +} + +static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + dlm_recover_master_reply(ls, rc_in); +} + +static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb, + struct rcom_lock *rl) +{ + memset(rl, 0, sizeof(*rl)); + + rl->rl_ownpid = lkb->lkb_ownpid; + rl->rl_lkid = lkb->lkb_id; + rl->rl_exflags = lkb->lkb_exflags; + rl->rl_flags = lkb->lkb_flags; + rl->rl_lvbseq = lkb->lkb_lvbseq; + rl->rl_rqmode = lkb->lkb_rqmode; + rl->rl_grmode = lkb->lkb_grmode; + rl->rl_status = lkb->lkb_status; + rl->rl_wait_type = lkb->lkb_wait_type; + + if (lkb->lkb_bastaddr) + rl->rl_asts |= AST_BAST; + if (lkb->lkb_astaddr) + rl->rl_asts |= AST_COMP; + + if (lkb->lkb_range) + memcpy(rl->rl_range, lkb->lkb_range, 4*sizeof(uint64_t)); + + rl->rl_namelen = r->res_length; + memcpy(rl->rl_name, r->res_name, r->res_length); + + /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ? + If so, receive_rcom_lock_args() won't take this copy. */ + + if (lkb->lkb_lvbptr) + memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen); +} + +int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb) +{ + struct dlm_ls *ls = r->res_ls; + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + struct rcom_lock *rl; + int error, len = sizeof(struct rcom_lock); + + if (lkb->lkb_lvbptr) + len += ls->ls_lvblen; + + error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh); + if (error) + goto out; + + rl = (struct rcom_lock *) rc->rc_buf; + pack_rcom_lock(r, lkb, rl); + rc->rc_id = (unsigned long) r; + + send_rcom(ls, mh, rc); + out: + return error; +} + +static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + int error, nodeid = rc_in->rc_header.h_nodeid; + + dlm_recover_master_copy(ls, rc_in); + + error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY, + sizeof(struct rcom_lock), &rc, &mh); + if (error) + return; + + /* We send back the same rcom_lock struct we received, but + dlm_recover_master_copy() has filled in rl_remid and rl_result */ + + memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock)); + rc->rc_id = rc_in->rc_id; + + send_rcom(ls, mh, rc); +} + +static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in) +{ + uint32_t status = dlm_recover_status(ls); + + if (!(status & DLM_RS_DIR)) { + log_debug(ls, "ignoring RCOM_LOCK_REPLY from %u", + rc_in->rc_header.h_nodeid); + return; + } + + dlm_recover_process_copy(ls, rc_in); +} + +static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in) +{ + struct dlm_rcom *rc; + struct dlm_mhandle *mh; + char *mb; + int mb_len = sizeof(struct dlm_rcom); + + mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb); + if (!mh) + return -ENOBUFS; + memset(mb, 0, mb_len); + + rc = (struct dlm_rcom *) mb; + + rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR); + rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace; + rc->rc_header.h_nodeid = dlm_our_nodeid(); + rc->rc_header.h_length = mb_len; + rc->rc_header.h_cmd = DLM_RCOM; + + rc->rc_type = DLM_RCOM_STATUS_REPLY; + rc->rc_result = -ESRCH; + + dlm_rcom_out(rc); + dlm_lowcomms_commit_buffer(mh); + + return 0; +} + +/* Called by dlm_recvd; corresponds to dlm_receive_message() but special + recovery-only comms are sent through here. */ + +void dlm_receive_rcom(struct dlm_header *hd, int nodeid) +{ + struct dlm_rcom *rc = (struct dlm_rcom *) hd; + struct dlm_ls *ls; + + dlm_rcom_in(rc); + + /* If the lockspace doesn't exist then still send a status message + back; it's possible that it just doesn't have its global_id yet. */ + + ls = dlm_find_lockspace_global(hd->h_lockspace); + if (!ls) { + log_print("lockspace %x from %d not found", + hd->h_lockspace, nodeid); + send_ls_not_ready(nodeid, rc); + return; + } + + if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) { + log_error(ls, "ignoring recovery message %x from %d", + rc->rc_type, nodeid); + goto out; + } + + if (nodeid != rc->rc_header.h_nodeid) { + log_error(ls, "bad rcom nodeid %d from %d", + rc->rc_header.h_nodeid, nodeid); + goto out; + } + + switch (rc->rc_type) { + case DLM_RCOM_STATUS: + receive_rcom_status(ls, rc); + break; + + case DLM_RCOM_NAMES: + receive_rcom_names(ls, rc); + break; + + case DLM_RCOM_LOOKUP: + receive_rcom_lookup(ls, rc); + break; + + case DLM_RCOM_LOCK: + receive_rcom_lock(ls, rc); + break; + + case DLM_RCOM_STATUS_REPLY: + receive_rcom_status_reply(ls, rc); + break; + + case DLM_RCOM_NAMES_REPLY: + receive_rcom_names_reply(ls, rc); + break; + + case DLM_RCOM_LOOKUP_REPLY: + receive_rcom_lookup_reply(ls, rc); + break; + + case DLM_RCOM_LOCK_REPLY: + receive_rcom_lock_reply(ls, rc); + break; + + default: + DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type);); + } + out: + dlm_put_lockspace(ls); +} + diff --git a/fs/dlm/rcom.h b/fs/dlm/rcom.h new file mode 100644 index 000000000000..d7984321ff41 --- /dev/null +++ b/fs/dlm/rcom.h @@ -0,0 +1,24 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __RCOM_DOT_H__ +#define __RCOM_DOT_H__ + +int dlm_rcom_status(struct dlm_ls *ls, int nodeid); +int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name,int last_len); +int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid); +int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb); +void dlm_receive_rcom(struct dlm_header *hd, int nodeid); + +#endif + diff --git a/fs/dlm/recover.c b/fs/dlm/recover.c new file mode 100644 index 000000000000..1712c97bc229 --- /dev/null +++ b/fs/dlm/recover.c @@ -0,0 +1,762 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "dir.h" +#include "config.h" +#include "ast.h" +#include "memory.h" +#include "rcom.h" +#include "lock.h" +#include "lowcomms.h" +#include "member.h" +#include "recover.h" + + +/* + * Recovery waiting routines: these functions wait for a particular reply from + * a remote node, or for the remote node to report a certain status. They need + * to abort if the lockspace is stopped indicating a node has failed (perhaps + * the one being waited for). + */ + +/* + * Wait until given function returns non-zero or lockspace is stopped + * (LS_RECOVERY_STOP set due to failure of a node in ls_nodes). When another + * function thinks it could have completed the waited-on task, they should wake + * up ls_wait_general to get an immediate response rather than waiting for the + * timer to detect the result. A timer wakes us up periodically while waiting + * to see if we should abort due to a node failure. This should only be called + * by the dlm_recoverd thread. + */ + +static void dlm_wait_timer_fn(unsigned long data) +{ + struct dlm_ls *ls = (struct dlm_ls *) data; + mod_timer(&ls->ls_timer, jiffies + (dlm_config.recover_timer * HZ)); + wake_up(&ls->ls_wait_general); +} + +int dlm_wait_function(struct dlm_ls *ls, int (*testfn) (struct dlm_ls *ls)) +{ + int error = 0; + + init_timer(&ls->ls_timer); + ls->ls_timer.function = dlm_wait_timer_fn; + ls->ls_timer.data = (long) ls; + ls->ls_timer.expires = jiffies + (dlm_config.recover_timer * HZ); + add_timer(&ls->ls_timer); + + wait_event(ls->ls_wait_general, testfn(ls) || dlm_recovery_stopped(ls)); + del_timer_sync(&ls->ls_timer); + + if (dlm_recovery_stopped(ls)) { + log_debug(ls, "dlm_wait_function aborted"); + error = -EINTR; + } + return error; +} + +/* + * An efficient way for all nodes to wait for all others to have a certain + * status. The node with the lowest nodeid polls all the others for their + * status (wait_status_all) and all the others poll the node with the low id + * for its accumulated result (wait_status_low). When all nodes have set + * status flag X, then status flag X_ALL will be set on the low nodeid. + */ + +uint32_t dlm_recover_status(struct dlm_ls *ls) +{ + uint32_t status; + spin_lock(&ls->ls_recover_lock); + status = ls->ls_recover_status; + spin_unlock(&ls->ls_recover_lock); + return status; +} + +void dlm_set_recover_status(struct dlm_ls *ls, uint32_t status) +{ + spin_lock(&ls->ls_recover_lock); + ls->ls_recover_status |= status; + spin_unlock(&ls->ls_recover_lock); +} + +static int wait_status_all(struct dlm_ls *ls, uint32_t wait_status) +{ + struct dlm_rcom *rc = (struct dlm_rcom *) ls->ls_recover_buf; + struct dlm_member *memb; + int error = 0, delay; + + list_for_each_entry(memb, &ls->ls_nodes, list) { + delay = 0; + for (;;) { + if (dlm_recovery_stopped(ls)) { + error = -EINTR; + goto out; + } + + error = dlm_rcom_status(ls, memb->nodeid); + if (error) + goto out; + + if (rc->rc_result & wait_status) + break; + if (delay < 1000) + delay += 20; + msleep(delay); + } + } + out: + return error; +} + +static int wait_status_low(struct dlm_ls *ls, uint32_t wait_status) +{ + struct dlm_rcom *rc = (struct dlm_rcom *) ls->ls_recover_buf; + int error = 0, delay = 0, nodeid = ls->ls_low_nodeid; + + for (;;) { + if (dlm_recovery_stopped(ls)) { + error = -EINTR; + goto out; + } + + error = dlm_rcom_status(ls, nodeid); + if (error) + break; + + if (rc->rc_result & wait_status) + break; + if (delay < 1000) + delay += 20; + msleep(delay); + } + out: + return error; +} + +static int wait_status(struct dlm_ls *ls, uint32_t status) +{ + uint32_t status_all = status << 1; + int error; + + if (ls->ls_low_nodeid == dlm_our_nodeid()) { + error = wait_status_all(ls, status); + if (!error) + dlm_set_recover_status(ls, status_all); + } else + error = wait_status_low(ls, status_all); + + return error; +} + +int dlm_recover_members_wait(struct dlm_ls *ls) +{ + return wait_status(ls, DLM_RS_NODES); +} + +int dlm_recover_directory_wait(struct dlm_ls *ls) +{ + return wait_status(ls, DLM_RS_DIR); +} + +int dlm_recover_locks_wait(struct dlm_ls *ls) +{ + return wait_status(ls, DLM_RS_LOCKS); +} + +int dlm_recover_done_wait(struct dlm_ls *ls) +{ + return wait_status(ls, DLM_RS_DONE); +} + +/* + * The recover_list contains all the rsb's for which we've requested the new + * master nodeid. As replies are returned from the resource directories the + * rsb's are removed from the list. When the list is empty we're done. + * + * The recover_list is later similarly used for all rsb's for which we've sent + * new lkb's and need to receive new corresponding lkid's. + * + * We use the address of the rsb struct as a simple local identifier for the + * rsb so we can match an rcom reply with the rsb it was sent for. + */ + +static int recover_list_empty(struct dlm_ls *ls) +{ + int empty; + + spin_lock(&ls->ls_recover_list_lock); + empty = list_empty(&ls->ls_recover_list); + spin_unlock(&ls->ls_recover_list_lock); + + return empty; +} + +static void recover_list_add(struct dlm_rsb *r) +{ + struct dlm_ls *ls = r->res_ls; + + spin_lock(&ls->ls_recover_list_lock); + if (list_empty(&r->res_recover_list)) { + list_add_tail(&r->res_recover_list, &ls->ls_recover_list); + ls->ls_recover_list_count++; + dlm_hold_rsb(r); + } + spin_unlock(&ls->ls_recover_list_lock); +} + +static void recover_list_del(struct dlm_rsb *r) +{ + struct dlm_ls *ls = r->res_ls; + + spin_lock(&ls->ls_recover_list_lock); + list_del_init(&r->res_recover_list); + ls->ls_recover_list_count--; + spin_unlock(&ls->ls_recover_list_lock); + + dlm_put_rsb(r); +} + +static struct dlm_rsb *recover_list_find(struct dlm_ls *ls, uint64_t id) +{ + struct dlm_rsb *r = NULL; + + spin_lock(&ls->ls_recover_list_lock); + + list_for_each_entry(r, &ls->ls_recover_list, res_recover_list) { + if (id == (unsigned long) r) + goto out; + } + r = NULL; + out: + spin_unlock(&ls->ls_recover_list_lock); + return r; +} + +static void recover_list_clear(struct dlm_ls *ls) +{ + struct dlm_rsb *r, *s; + + spin_lock(&ls->ls_recover_list_lock); + list_for_each_entry_safe(r, s, &ls->ls_recover_list, res_recover_list) { + list_del_init(&r->res_recover_list); + dlm_put_rsb(r); + ls->ls_recover_list_count--; + } + + if (ls->ls_recover_list_count != 0) { + log_error(ls, "warning: recover_list_count %d", + ls->ls_recover_list_count); + ls->ls_recover_list_count = 0; + } + spin_unlock(&ls->ls_recover_list_lock); +} + + +/* Master recovery: find new master node for rsb's that were + mastered on nodes that have been removed. + + dlm_recover_masters + recover_master + dlm_send_rcom_lookup -> receive_rcom_lookup + dlm_dir_lookup + receive_rcom_lookup_reply <- + dlm_recover_master_reply + set_new_master + set_master_lkbs + set_lock_master +*/ + +/* + * Set the lock master for all LKBs in a lock queue + * If we are the new master of the rsb, we may have received new + * MSTCPY locks from other nodes already which we need to ignore + * when setting the new nodeid. + */ + +static void set_lock_master(struct list_head *queue, int nodeid) +{ + struct dlm_lkb *lkb; + + list_for_each_entry(lkb, queue, lkb_statequeue) + if (!(lkb->lkb_flags & DLM_IFL_MSTCPY)) + lkb->lkb_nodeid = nodeid; +} + +static void set_master_lkbs(struct dlm_rsb *r) +{ + set_lock_master(&r->res_grantqueue, r->res_nodeid); + set_lock_master(&r->res_convertqueue, r->res_nodeid); + set_lock_master(&r->res_waitqueue, r->res_nodeid); +} + +/* + * Propogate the new master nodeid to locks + * The NEW_MASTER flag tells dlm_recover_locks() which rsb's to consider. + * The NEW_MASTER2 flag tells recover_lvb() which rsb's to consider. + */ + +static void set_new_master(struct dlm_rsb *r, int nodeid) +{ + lock_rsb(r); + r->res_nodeid = nodeid; + set_master_lkbs(r); + rsb_set_flag(r, RSB_NEW_MASTER); + rsb_set_flag(r, RSB_NEW_MASTER2); + unlock_rsb(r); +} + +/* + * We do async lookups on rsb's that need new masters. The rsb's + * waiting for a lookup reply are kept on the recover_list. + */ + +static int recover_master(struct dlm_rsb *r) +{ + struct dlm_ls *ls = r->res_ls; + int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid(); + + dir_nodeid = dlm_dir_nodeid(r); + + if (dir_nodeid == our_nodeid) { + error = dlm_dir_lookup(ls, our_nodeid, r->res_name, + r->res_length, &ret_nodeid); + if (error) + log_error(ls, "recover dir lookup error %d", error); + + if (ret_nodeid == our_nodeid) + ret_nodeid = 0; + set_new_master(r, ret_nodeid); + } else { + recover_list_add(r); + error = dlm_send_rcom_lookup(r, dir_nodeid); + } + + return error; +} + +/* + * When not using a directory, most resource names will hash to a new static + * master nodeid and the resource will need to be remastered. + */ + +static int recover_master_static(struct dlm_rsb *r) +{ + int master = dlm_dir_nodeid(r); + + if (master == dlm_our_nodeid()) + master = 0; + + if (r->res_nodeid != master) { + if (is_master(r)) + dlm_purge_mstcpy_locks(r); + set_new_master(r, master); + return 1; + } + return 0; +} + +/* + * Go through local root resources and for each rsb which has a master which + * has departed, get the new master nodeid from the directory. The dir will + * assign mastery to the first node to look up the new master. That means + * we'll discover in this lookup if we're the new master of any rsb's. + * + * We fire off all the dir lookup requests individually and asynchronously to + * the correct dir node. + */ + +int dlm_recover_masters(struct dlm_ls *ls) +{ + struct dlm_rsb *r; + int error = 0, count = 0; + + log_debug(ls, "dlm_recover_masters"); + + down_read(&ls->ls_root_sem); + list_for_each_entry(r, &ls->ls_root_list, res_root_list) { + if (dlm_recovery_stopped(ls)) { + up_read(&ls->ls_root_sem); + error = -EINTR; + goto out; + } + + if (dlm_no_directory(ls)) + count += recover_master_static(r); + else if (!is_master(r) && dlm_is_removed(ls, r->res_nodeid)) { + recover_master(r); + count++; + } + + schedule(); + } + up_read(&ls->ls_root_sem); + + log_debug(ls, "dlm_recover_masters %d resources", count); + + error = dlm_wait_function(ls, &recover_list_empty); + out: + if (error) + recover_list_clear(ls); + return error; +} + +int dlm_recover_master_reply(struct dlm_ls *ls, struct dlm_rcom *rc) +{ + struct dlm_rsb *r; + int nodeid; + + r = recover_list_find(ls, rc->rc_id); + if (!r) { + log_error(ls, "dlm_recover_master_reply no id %"PRIx64"", + rc->rc_id); + goto out; + } + + nodeid = rc->rc_result; + if (nodeid == dlm_our_nodeid()) + nodeid = 0; + + set_new_master(r, nodeid); + recover_list_del(r); + + if (recover_list_empty(ls)) + wake_up(&ls->ls_wait_general); + out: + return 0; +} + + +/* Lock recovery: rebuild the process-copy locks we hold on a + remastered rsb on the new rsb master. + + dlm_recover_locks + recover_locks + recover_locks_queue + dlm_send_rcom_lock -> receive_rcom_lock + dlm_recover_master_copy + receive_rcom_lock_reply <- + dlm_recover_process_copy +*/ + + +/* + * keep a count of the number of lkb's we send to the new master; when we get + * an equal number of replies then recovery for the rsb is done + */ + +static int recover_locks_queue(struct dlm_rsb *r, struct list_head *head) +{ + struct dlm_lkb *lkb; + int error = 0; + + list_for_each_entry(lkb, head, lkb_statequeue) { + error = dlm_send_rcom_lock(r, lkb); + if (error) + break; + r->res_recover_locks_count++; + } + + return error; +} + +static int all_queues_empty(struct dlm_rsb *r) +{ + if (!list_empty(&r->res_grantqueue) || + !list_empty(&r->res_convertqueue) || + !list_empty(&r->res_waitqueue)) + return FALSE; + return TRUE; +} + +static int recover_locks(struct dlm_rsb *r) +{ + int error = 0; + + lock_rsb(r); + if (all_queues_empty(r)) + goto out; + + DLM_ASSERT(!r->res_recover_locks_count, dlm_print_rsb(r);); + + error = recover_locks_queue(r, &r->res_grantqueue); + if (error) + goto out; + error = recover_locks_queue(r, &r->res_convertqueue); + if (error) + goto out; + error = recover_locks_queue(r, &r->res_waitqueue); + if (error) + goto out; + + if (r->res_recover_locks_count) + recover_list_add(r); + else + rsb_clear_flag(r, RSB_NEW_MASTER); + out: + unlock_rsb(r); + return error; +} + +int dlm_recover_locks(struct dlm_ls *ls) +{ + struct dlm_rsb *r; + int error, count = 0; + + log_debug(ls, "dlm_recover_locks"); + + down_read(&ls->ls_root_sem); + list_for_each_entry(r, &ls->ls_root_list, res_root_list) { + if (is_master(r)) { + rsb_clear_flag(r, RSB_NEW_MASTER); + continue; + } + + if (!rsb_flag(r, RSB_NEW_MASTER)) + continue; + + if (dlm_recovery_stopped(ls)) { + error = -EINTR; + up_read(&ls->ls_root_sem); + goto out; + } + + error = recover_locks(r); + if (error) { + up_read(&ls->ls_root_sem); + goto out; + } + + count += r->res_recover_locks_count; + } + up_read(&ls->ls_root_sem); + + log_debug(ls, "dlm_recover_locks %d locks", count); + + error = dlm_wait_function(ls, &recover_list_empty); + out: + if (error) + recover_list_clear(ls); + else + dlm_set_recover_status(ls, DLM_RS_LOCKS); + return error; +} + +void dlm_recovered_lock(struct dlm_rsb *r) +{ + DLM_ASSERT(rsb_flag(r, RSB_NEW_MASTER), dlm_print_rsb(r);); + + r->res_recover_locks_count--; + if (!r->res_recover_locks_count) { + rsb_clear_flag(r, RSB_NEW_MASTER); + recover_list_del(r); + } + + if (recover_list_empty(r->res_ls)) + wake_up(&r->res_ls->ls_wait_general); +} + +/* + * The lvb needs to be recovered on all master rsb's. This includes setting + * the VALNOTVALID flag if necessary, and determining the correct lvb contents + * based on the lvb's of the locks held on the rsb. + * + * RSB_VALNOTVALID is set if there are only NL/CR locks on the rsb. If it + * was already set prior to recovery, it's not cleared, regardless of locks. + * + * The LVB contents are only considered for changing when this is a new master + * of the rsb (NEW_MASTER2). Then, the rsb's lvb is taken from any lkb with + * mode > CR. If no lkb's exist with mode above CR, the lvb contents are taken + * from the lkb with the largest lvb sequence number. + */ + +static void recover_lvb(struct dlm_rsb *r) +{ + struct dlm_lkb *lkb, *high_lkb = NULL; + uint32_t high_seq = 0; + int lock_lvb_exists = FALSE; + int big_lock_exists = FALSE; + int lvblen = r->res_ls->ls_lvblen; + + list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) { + if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + continue; + + lock_lvb_exists = TRUE; + + if (lkb->lkb_grmode > DLM_LOCK_CR) { + big_lock_exists = TRUE; + goto setflag; + } + + if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) { + high_lkb = lkb; + high_seq = lkb->lkb_lvbseq; + } + } + + list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) { + if (!(lkb->lkb_exflags & DLM_LKF_VALBLK)) + continue; + + lock_lvb_exists = TRUE; + + if (lkb->lkb_grmode > DLM_LOCK_CR) { + big_lock_exists = TRUE; + goto setflag; + } + + if (((int)lkb->lkb_lvbseq - (int)high_seq) >= 0) { + high_lkb = lkb; + high_seq = lkb->lkb_lvbseq; + } + } + + setflag: + if (!lock_lvb_exists) + goto out; + + if (!big_lock_exists) + rsb_set_flag(r, RSB_VALNOTVALID); + + /* don't mess with the lvb unless we're the new master */ + if (!rsb_flag(r, RSB_NEW_MASTER2)) + goto out; + + if (!r->res_lvbptr) { + r->res_lvbptr = allocate_lvb(r->res_ls); + if (!r->res_lvbptr) + goto out; + } + + if (big_lock_exists) { + r->res_lvbseq = lkb->lkb_lvbseq; + memcpy(r->res_lvbptr, lkb->lkb_lvbptr, lvblen); + } else if (high_lkb) { + r->res_lvbseq = high_lkb->lkb_lvbseq; + memcpy(r->res_lvbptr, high_lkb->lkb_lvbptr, lvblen); + } else { + r->res_lvbseq = 0; + memset(r->res_lvbptr, 0, lvblen); + } + out: + return; +} + +/* All master rsb's flagged RECOVER_CONVERT need to be looked at. The locks + converting PR->CW or CW->PR need to have their lkb_grmode set. */ + +static void recover_conversion(struct dlm_rsb *r) +{ + struct dlm_lkb *lkb; + int grmode = -1; + + list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) { + if (lkb->lkb_grmode == DLM_LOCK_PR || + lkb->lkb_grmode == DLM_LOCK_CW) { + grmode = lkb->lkb_grmode; + break; + } + } + + list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) { + if (lkb->lkb_grmode != DLM_LOCK_IV) + continue; + if (grmode == -1) + lkb->lkb_grmode = lkb->lkb_rqmode; + else + lkb->lkb_grmode = grmode; + } +} + +void dlm_recover_rsbs(struct dlm_ls *ls) +{ + struct dlm_rsb *r; + int count = 0; + + log_debug(ls, "dlm_recover_rsbs"); + + down_read(&ls->ls_root_sem); + list_for_each_entry(r, &ls->ls_root_list, res_root_list) { + lock_rsb(r); + if (is_master(r)) { + if (rsb_flag(r, RSB_RECOVER_CONVERT)) + recover_conversion(r); + recover_lvb(r); + count++; + } + rsb_clear_flag(r, RSB_RECOVER_CONVERT); + unlock_rsb(r); + } + up_read(&ls->ls_root_sem); + + log_debug(ls, "dlm_recover_rsbs %d rsbs", count); +} + +/* Create a single list of all root rsb's to be used during recovery */ + +int dlm_create_root_list(struct dlm_ls *ls) +{ + struct dlm_rsb *r; + int i, error = 0; + + down_write(&ls->ls_root_sem); + if (!list_empty(&ls->ls_root_list)) { + log_error(ls, "root list not empty"); + error = -EINVAL; + goto out; + } + + for (i = 0; i < ls->ls_rsbtbl_size; i++) { + read_lock(&ls->ls_rsbtbl[i].lock); + list_for_each_entry(r, &ls->ls_rsbtbl[i].list, res_hashchain) { + list_add(&r->res_root_list, &ls->ls_root_list); + dlm_hold_rsb(r); + } + read_unlock(&ls->ls_rsbtbl[i].lock); + } + out: + up_write(&ls->ls_root_sem); + return error; +} + +void dlm_release_root_list(struct dlm_ls *ls) +{ + struct dlm_rsb *r, *safe; + + down_write(&ls->ls_root_sem); + list_for_each_entry_safe(r, safe, &ls->ls_root_list, res_root_list) { + list_del_init(&r->res_root_list); + dlm_put_rsb(r); + } + up_write(&ls->ls_root_sem); +} + +void dlm_clear_toss_list(struct dlm_ls *ls) +{ + struct dlm_rsb *r, *safe; + int i; + + for (i = 0; i < ls->ls_rsbtbl_size; i++) { + write_lock(&ls->ls_rsbtbl[i].lock); + list_for_each_entry_safe(r, safe, &ls->ls_rsbtbl[i].toss, + res_hashchain) { + list_del(&r->res_hashchain); + free_rsb(r); + } + write_unlock(&ls->ls_rsbtbl[i].lock); + } +} + diff --git a/fs/dlm/recover.h b/fs/dlm/recover.h new file mode 100644 index 000000000000..ebd0363f1e08 --- /dev/null +++ b/fs/dlm/recover.h @@ -0,0 +1,34 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __RECOVER_DOT_H__ +#define __RECOVER_DOT_H__ + +int dlm_wait_function(struct dlm_ls *ls, int (*testfn) (struct dlm_ls *ls)); +uint32_t dlm_recover_status(struct dlm_ls *ls); +void dlm_set_recover_status(struct dlm_ls *ls, uint32_t status); +int dlm_recover_members_wait(struct dlm_ls *ls); +int dlm_recover_directory_wait(struct dlm_ls *ls); +int dlm_recover_locks_wait(struct dlm_ls *ls); +int dlm_recover_done_wait(struct dlm_ls *ls); +int dlm_recover_masters(struct dlm_ls *ls); +int dlm_recover_master_reply(struct dlm_ls *ls, struct dlm_rcom *rc); +int dlm_recover_locks(struct dlm_ls *ls); +void dlm_recovered_lock(struct dlm_rsb *r); +int dlm_create_root_list(struct dlm_ls *ls); +void dlm_release_root_list(struct dlm_ls *ls); +void dlm_clear_toss_list(struct dlm_ls *ls); +void dlm_recover_rsbs(struct dlm_ls *ls); + +#endif /* __RECOVER_DOT_H__ */ + diff --git a/fs/dlm/recoverd.c b/fs/dlm/recoverd.c new file mode 100644 index 000000000000..06e4f7cab6e7 --- /dev/null +++ b/fs/dlm/recoverd.c @@ -0,0 +1,285 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "lockspace.h" +#include "member.h" +#include "dir.h" +#include "ast.h" +#include "recover.h" +#include "lowcomms.h" +#include "lock.h" +#include "requestqueue.h" +#include "recoverd.h" + + +/* If the start for which we're re-enabling locking (seq) has been superseded + by a newer stop (ls_recover_seq), we need to leave locking disabled. */ + +static int enable_locking(struct dlm_ls *ls, uint64_t seq) +{ + int error = -EINTR; + + spin_lock(&ls->ls_recover_lock); + if (ls->ls_recover_seq == seq) { + set_bit(LSFL_RUNNING, &ls->ls_flags); + up_write(&ls->ls_in_recovery); + error = 0; + } + spin_unlock(&ls->ls_recover_lock); + return error; +} + +static int ls_recover(struct dlm_ls *ls, struct dlm_recover *rv) +{ + unsigned long start; + int error, neg = 0; + + log_debug(ls, "recover %"PRIx64"", rv->seq); + + down(&ls->ls_recoverd_active); + + /* + * Suspending and resuming dlm_astd ensures that no lkb's from this ls + * will be processed by dlm_astd during recovery. + */ + + dlm_astd_suspend(); + dlm_astd_resume(); + + /* + * This list of root rsb's will be the basis of most of the recovery + * routines. + */ + + dlm_create_root_list(ls); + + /* + * Free all the tossed rsb's so we don't have to recover them. + */ + + dlm_clear_toss_list(ls); + + /* + * Add or remove nodes from the lockspace's ls_nodes list. + * Also waits for all nodes to complete dlm_recover_members. + */ + + error = dlm_recover_members(ls, rv, &neg); + if (error) { + log_error(ls, "recover_members failed %d", error); + goto fail; + } + start = jiffies; + + /* + * Rebuild our own share of the directory by collecting from all other + * nodes their master rsb names that hash to us. + */ + + error = dlm_recover_directory(ls); + if (error) { + log_error(ls, "recover_directory failed %d", error); + goto fail; + } + + /* + * Purge directory-related requests that are saved in requestqueue. + * All dir requests from before recovery are invalid now due to the dir + * rebuild and will be resent by the requesting nodes. + */ + + dlm_purge_requestqueue(ls); + + /* + * Wait for all nodes to complete directory rebuild. + */ + + error = dlm_recover_directory_wait(ls); + if (error) { + log_error(ls, "recover_directory_wait failed %d", error); + goto fail; + } + + /* + * We may have outstanding operations that are waiting for a reply from + * a failed node. Mark these to be resent after recovery. Unlock and + * cancel ops can just be completed. + */ + + dlm_recover_waiters_pre(ls); + + error = dlm_recovery_stopped(ls); + if (error) + goto fail; + + if (neg || dlm_no_directory(ls)) { + /* + * Clear lkb's for departed nodes. + */ + + dlm_purge_locks(ls); + + /* + * Get new master nodeid's for rsb's that were mastered on + * departed nodes. + */ + + error = dlm_recover_masters(ls); + if (error) { + log_error(ls, "recover_masters failed %d", error); + goto fail; + } + + /* + * Send our locks on remastered rsb's to the new masters. + */ + + error = dlm_recover_locks(ls); + if (error) { + log_error(ls, "recover_locks failed %d", error); + goto fail; + } + + error = dlm_recover_locks_wait(ls); + if (error) { + log_error(ls, "recover_locks_wait failed %d", error); + goto fail; + } + + /* + * Finalize state in master rsb's now that all locks can be + * checked. This includes conversion resolution and lvb + * settings. + */ + + dlm_recover_rsbs(ls); + } + + dlm_release_root_list(ls); + + dlm_set_recover_status(ls, DLM_RS_DONE); + error = dlm_recover_done_wait(ls); + if (error) { + log_error(ls, "recover_done_wait failed %d", error); + goto fail; + } + + dlm_clear_members_gone(ls); + + error = enable_locking(ls, rv->seq); + if (error) { + log_error(ls, "enable_locking failed %d", error); + goto fail; + } + + error = dlm_process_requestqueue(ls); + if (error) { + log_error(ls, "process_requestqueue failed %d", error); + goto fail; + } + + error = dlm_recover_waiters_post(ls); + if (error) { + log_error(ls, "recover_waiters_post failed %d", error); + goto fail; + } + + dlm_grant_after_purge(ls); + + dlm_astd_wake(); + + log_debug(ls, "recover %"PRIx64" done: %u ms", rv->seq, + jiffies_to_msecs(jiffies - start)); + up(&ls->ls_recoverd_active); + + return 0; + + fail: + dlm_release_root_list(ls); + log_debug(ls, "recover %"PRIx64" error %d", rv->seq, error); + up(&ls->ls_recoverd_active); + return error; +} + +static void do_ls_recovery(struct dlm_ls *ls) +{ + struct dlm_recover *rv = NULL; + + spin_lock(&ls->ls_recover_lock); + rv = ls->ls_recover_args; + ls->ls_recover_args = NULL; + clear_bit(LSFL_RECOVERY_STOP, &ls->ls_flags); + spin_unlock(&ls->ls_recover_lock); + + if (rv) { + ls_recover(ls, rv); + kfree(rv->nodeids); + kfree(rv); + } +} + +static int dlm_recoverd(void *arg) +{ + struct dlm_ls *ls; + + ls = dlm_find_lockspace_local(arg); + + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + if (!test_bit(LSFL_WORK, &ls->ls_flags)) + schedule(); + set_current_state(TASK_RUNNING); + + if (test_and_clear_bit(LSFL_WORK, &ls->ls_flags)) + do_ls_recovery(ls); + } + + dlm_put_lockspace(ls); + return 0; +} + +void dlm_recoverd_kick(struct dlm_ls *ls) +{ + set_bit(LSFL_WORK, &ls->ls_flags); + wake_up_process(ls->ls_recoverd_task); +} + +int dlm_recoverd_start(struct dlm_ls *ls) +{ + struct task_struct *p; + int error = 0; + + p = kthread_run(dlm_recoverd, ls, "dlm_recoverd"); + if (IS_ERR(p)) + error = PTR_ERR(p); + else + ls->ls_recoverd_task = p; + return error; +} + +void dlm_recoverd_stop(struct dlm_ls *ls) +{ + kthread_stop(ls->ls_recoverd_task); +} + +void dlm_recoverd_suspend(struct dlm_ls *ls) +{ + down(&ls->ls_recoverd_active); +} + +void dlm_recoverd_resume(struct dlm_ls *ls) +{ + up(&ls->ls_recoverd_active); +} + diff --git a/fs/dlm/recoverd.h b/fs/dlm/recoverd.h new file mode 100644 index 000000000000..866657c5d69d --- /dev/null +++ b/fs/dlm/recoverd.h @@ -0,0 +1,24 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __RECOVERD_DOT_H__ +#define __RECOVERD_DOT_H__ + +void dlm_recoverd_kick(struct dlm_ls *ls); +void dlm_recoverd_stop(struct dlm_ls *ls); +int dlm_recoverd_start(struct dlm_ls *ls); +void dlm_recoverd_suspend(struct dlm_ls *ls); +void dlm_recoverd_resume(struct dlm_ls *ls); + +#endif /* __RECOVERD_DOT_H__ */ + diff --git a/fs/dlm/requestqueue.c b/fs/dlm/requestqueue.c new file mode 100644 index 000000000000..36afe99e4f93 --- /dev/null +++ b/fs/dlm/requestqueue.c @@ -0,0 +1,184 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "member.h" +#include "lock.h" +#include "dir.h" +#include "config.h" +#include "requestqueue.h" + +struct rq_entry { + struct list_head list; + int nodeid; + char request[1]; +}; + +/* + * Requests received while the lockspace is in recovery get added to the + * request queue and processed when recovery is complete. This happens when + * the lockspace is suspended on some nodes before it is on others, or the + * lockspace is enabled on some while still suspended on others. + */ + +void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid, struct dlm_header *hd) +{ + struct rq_entry *e; + int length = hd->h_length; + + if (dlm_is_removed(ls, nodeid)) + return; + + e = kmalloc(sizeof(struct rq_entry) + length, GFP_KERNEL); + if (!e) { + log_print("dlm_add_requestqueue: out of memory\n"); + return; + } + + e->nodeid = nodeid; + memcpy(e->request, hd, length); + + down(&ls->ls_requestqueue_lock); + list_add_tail(&e->list, &ls->ls_requestqueue); + up(&ls->ls_requestqueue_lock); +} + +int dlm_process_requestqueue(struct dlm_ls *ls) +{ + struct rq_entry *e; + struct dlm_header *hd; + int error = 0; + + down(&ls->ls_requestqueue_lock); + + for (;;) { + if (list_empty(&ls->ls_requestqueue)) { + up(&ls->ls_requestqueue_lock); + error = 0; + break; + } + e = list_entry(ls->ls_requestqueue.next, struct rq_entry, list); + up(&ls->ls_requestqueue_lock); + + hd = (struct dlm_header *) e->request; + error = dlm_receive_message(hd, e->nodeid, TRUE); + + if (error == -EINTR) { + /* entry is left on requestqueue */ + log_debug(ls, "process_requestqueue abort eintr"); + break; + } + + down(&ls->ls_requestqueue_lock); + list_del(&e->list); + kfree(e); + + if (dlm_locking_stopped(ls)) { + log_debug(ls, "process_requestqueue abort running"); + up(&ls->ls_requestqueue_lock); + error = -EINTR; + break; + } + schedule(); + } + + return error; +} + +/* + * After recovery is done, locking is resumed and dlm_recoverd takes all the + * saved requests and processes them as they would have been by dlm_recvd. At + * the same time, dlm_recvd will start receiving new requests from remote + * nodes. We want to delay dlm_recvd processing new requests until + * dlm_recoverd has finished processing the old saved requests. + */ + +void dlm_wait_requestqueue(struct dlm_ls *ls) +{ + for (;;) { + down(&ls->ls_requestqueue_lock); + if (list_empty(&ls->ls_requestqueue)) + break; + if (dlm_locking_stopped(ls)) + break; + up(&ls->ls_requestqueue_lock); + schedule(); + } + up(&ls->ls_requestqueue_lock); +} + +static int purge_request(struct dlm_ls *ls, struct dlm_message *ms, int nodeid) +{ + uint32_t type = ms->m_type; + + if (dlm_is_removed(ls, nodeid)) + return 1; + + /* directory operations are always purged because the directory is + always rebuilt during recovery and the lookups resent */ + + if (type == DLM_MSG_REMOVE || + type == DLM_MSG_LOOKUP || + type == DLM_MSG_LOOKUP_REPLY) + return 1; + + if (!dlm_no_directory(ls)) + return 0; + + /* with no directory, the master is likely to change as a part of + recovery; requests to/from the defunct master need to be purged */ + + switch (type) { + case DLM_MSG_REQUEST: + case DLM_MSG_CONVERT: + case DLM_MSG_UNLOCK: + case DLM_MSG_CANCEL: + /* we're no longer the master of this resource, the sender + will resend to the new master (see waiter_needs_recovery) */ + + if (dlm_hash2nodeid(ls, ms->m_hash) != dlm_our_nodeid()) + return 1; + break; + + case DLM_MSG_REQUEST_REPLY: + case DLM_MSG_CONVERT_REPLY: + case DLM_MSG_UNLOCK_REPLY: + case DLM_MSG_CANCEL_REPLY: + case DLM_MSG_GRANT: + /* this reply is from the former master of the resource, + we'll resend to the new master if needed */ + + if (dlm_hash2nodeid(ls, ms->m_hash) != nodeid) + return 1; + break; + } + + return 0; +} + +void dlm_purge_requestqueue(struct dlm_ls *ls) +{ + struct dlm_message *ms; + struct rq_entry *e, *safe; + + down(&ls->ls_requestqueue_lock); + list_for_each_entry_safe(e, safe, &ls->ls_requestqueue, list) { + ms = (struct dlm_message *) e->request; + + if (purge_request(ls, ms, e->nodeid)) { + list_del(&e->list); + kfree(e); + } + } + up(&ls->ls_requestqueue_lock); +} + diff --git a/fs/dlm/requestqueue.h b/fs/dlm/requestqueue.h new file mode 100644 index 000000000000..349f0d292d95 --- /dev/null +++ b/fs/dlm/requestqueue.h @@ -0,0 +1,22 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __REQUESTQUEUE_DOT_H__ +#define __REQUESTQUEUE_DOT_H__ + +void dlm_add_requestqueue(struct dlm_ls *ls, int nodeid, struct dlm_header *hd); +int dlm_process_requestqueue(struct dlm_ls *ls); +void dlm_wait_requestqueue(struct dlm_ls *ls); +void dlm_purge_requestqueue(struct dlm_ls *ls); + +#endif + diff --git a/fs/dlm/util.c b/fs/dlm/util.c new file mode 100644 index 000000000000..826d122edf55 --- /dev/null +++ b/fs/dlm/util.c @@ -0,0 +1,173 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#include "dlm_internal.h" +#include "rcom.h" +#include "util.h" + +static void header_out(struct dlm_header *hd) +{ + hd->h_version = cpu_to_le32(hd->h_version); + hd->h_lockspace = cpu_to_le32(hd->h_lockspace); + hd->h_nodeid = cpu_to_le32(hd->h_nodeid); + hd->h_length = cpu_to_le16(hd->h_length); +} + +static void header_in(struct dlm_header *hd) +{ + hd->h_version = le32_to_cpu(hd->h_version); + hd->h_lockspace = le32_to_cpu(hd->h_lockspace); + hd->h_nodeid = le32_to_cpu(hd->h_nodeid); + hd->h_length = le16_to_cpu(hd->h_length); +} + +void dlm_message_out(struct dlm_message *ms) +{ + struct dlm_header *hd = (struct dlm_header *) ms; + + header_out(hd); + + ms->m_type = cpu_to_le32(ms->m_type); + ms->m_nodeid = cpu_to_le32(ms->m_nodeid); + ms->m_pid = cpu_to_le32(ms->m_pid); + ms->m_lkid = cpu_to_le32(ms->m_lkid); + ms->m_remid = cpu_to_le32(ms->m_remid); + ms->m_parent_lkid = cpu_to_le32(ms->m_parent_lkid); + ms->m_parent_remid = cpu_to_le32(ms->m_parent_remid); + ms->m_exflags = cpu_to_le32(ms->m_exflags); + ms->m_sbflags = cpu_to_le32(ms->m_sbflags); + ms->m_flags = cpu_to_le32(ms->m_flags); + ms->m_lvbseq = cpu_to_le32(ms->m_lvbseq); + ms->m_hash = cpu_to_le32(ms->m_hash); + ms->m_status = cpu_to_le32(ms->m_status); + ms->m_grmode = cpu_to_le32(ms->m_grmode); + ms->m_rqmode = cpu_to_le32(ms->m_rqmode); + ms->m_bastmode = cpu_to_le32(ms->m_bastmode); + ms->m_asts = cpu_to_le32(ms->m_asts); + ms->m_result = cpu_to_le32(ms->m_result); + ms->m_range[0] = cpu_to_le64(ms->m_range[0]); + ms->m_range[1] = cpu_to_le64(ms->m_range[1]); +} + +void dlm_message_in(struct dlm_message *ms) +{ + struct dlm_header *hd = (struct dlm_header *) ms; + + header_in(hd); + + ms->m_type = le32_to_cpu(ms->m_type); + ms->m_nodeid = le32_to_cpu(ms->m_nodeid); + ms->m_pid = le32_to_cpu(ms->m_pid); + ms->m_lkid = le32_to_cpu(ms->m_lkid); + ms->m_remid = le32_to_cpu(ms->m_remid); + ms->m_parent_lkid = le32_to_cpu(ms->m_parent_lkid); + ms->m_parent_remid = le32_to_cpu(ms->m_parent_remid); + ms->m_exflags = le32_to_cpu(ms->m_exflags); + ms->m_sbflags = le32_to_cpu(ms->m_sbflags); + ms->m_flags = le32_to_cpu(ms->m_flags); + ms->m_lvbseq = le32_to_cpu(ms->m_lvbseq); + ms->m_hash = le32_to_cpu(ms->m_hash); + ms->m_status = le32_to_cpu(ms->m_status); + ms->m_grmode = le32_to_cpu(ms->m_grmode); + ms->m_rqmode = le32_to_cpu(ms->m_rqmode); + ms->m_bastmode = le32_to_cpu(ms->m_bastmode); + ms->m_asts = le32_to_cpu(ms->m_asts); + ms->m_result = le32_to_cpu(ms->m_result); + ms->m_range[0] = le64_to_cpu(ms->m_range[0]); + ms->m_range[1] = le64_to_cpu(ms->m_range[1]); +} + +static void rcom_lock_out(struct rcom_lock *rl) +{ + rl->rl_ownpid = cpu_to_le32(rl->rl_ownpid); + rl->rl_lkid = cpu_to_le32(rl->rl_lkid); + rl->rl_remid = cpu_to_le32(rl->rl_remid); + rl->rl_parent_lkid = cpu_to_le32(rl->rl_parent_lkid); + rl->rl_parent_remid = cpu_to_le32(rl->rl_parent_remid); + rl->rl_exflags = cpu_to_le32(rl->rl_exflags); + rl->rl_flags = cpu_to_le32(rl->rl_flags); + rl->rl_lvbseq = cpu_to_le32(rl->rl_lvbseq); + rl->rl_result = cpu_to_le32(rl->rl_result); + rl->rl_wait_type = cpu_to_le16(rl->rl_wait_type); + rl->rl_namelen = cpu_to_le16(rl->rl_namelen); + rl->rl_range[0] = cpu_to_le64(rl->rl_range[0]); + rl->rl_range[1] = cpu_to_le64(rl->rl_range[1]); + rl->rl_range[2] = cpu_to_le64(rl->rl_range[2]); + rl->rl_range[3] = cpu_to_le64(rl->rl_range[3]); +} + +static void rcom_lock_in(struct rcom_lock *rl) +{ + rl->rl_ownpid = le32_to_cpu(rl->rl_ownpid); + rl->rl_lkid = le32_to_cpu(rl->rl_lkid); + rl->rl_remid = le32_to_cpu(rl->rl_remid); + rl->rl_parent_lkid = le32_to_cpu(rl->rl_parent_lkid); + rl->rl_parent_remid = le32_to_cpu(rl->rl_parent_remid); + rl->rl_exflags = le32_to_cpu(rl->rl_exflags); + rl->rl_flags = le32_to_cpu(rl->rl_flags); + rl->rl_lvbseq = le32_to_cpu(rl->rl_lvbseq); + rl->rl_result = le32_to_cpu(rl->rl_result); + rl->rl_wait_type = le16_to_cpu(rl->rl_wait_type); + rl->rl_namelen = le16_to_cpu(rl->rl_namelen); + rl->rl_range[0] = le64_to_cpu(rl->rl_range[0]); + rl->rl_range[1] = le64_to_cpu(rl->rl_range[1]); + rl->rl_range[2] = le64_to_cpu(rl->rl_range[2]); + rl->rl_range[3] = le64_to_cpu(rl->rl_range[3]); +} + +static void rcom_config_out(struct rcom_config *rf) +{ + rf->rf_lvblen = cpu_to_le32(rf->rf_lvblen); + rf->rf_lsflags = cpu_to_le32(rf->rf_lsflags); +} + +static void rcom_config_in(struct rcom_config *rf) +{ + rf->rf_lvblen = le32_to_cpu(rf->rf_lvblen); + rf->rf_lsflags = le32_to_cpu(rf->rf_lsflags); +} + +void dlm_rcom_out(struct dlm_rcom *rc) +{ + struct dlm_header *hd = (struct dlm_header *) rc; + int type = rc->rc_type; + + header_out(hd); + + rc->rc_type = cpu_to_le32(rc->rc_type); + rc->rc_result = cpu_to_le32(rc->rc_result); + rc->rc_id = cpu_to_le64(rc->rc_id); + + if (type == DLM_RCOM_LOCK) + rcom_lock_out((struct rcom_lock *) rc->rc_buf); + + else if (type == DLM_RCOM_STATUS_REPLY) + rcom_config_out((struct rcom_config *) rc->rc_buf); +} + +void dlm_rcom_in(struct dlm_rcom *rc) +{ + struct dlm_header *hd = (struct dlm_header *) rc; + + header_in(hd); + + rc->rc_type = le32_to_cpu(rc->rc_type); + rc->rc_result = le32_to_cpu(rc->rc_result); + rc->rc_id = le64_to_cpu(rc->rc_id); + + if (rc->rc_type == DLM_RCOM_LOCK) + rcom_lock_in((struct rcom_lock *) rc->rc_buf); + + else if (rc->rc_type == DLM_RCOM_STATUS_REPLY) + rcom_config_in((struct rcom_config *) rc->rc_buf); +} + diff --git a/fs/dlm/util.h b/fs/dlm/util.h new file mode 100644 index 000000000000..2b25915161c0 --- /dev/null +++ b/fs/dlm/util.h @@ -0,0 +1,22 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) 2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __UTIL_DOT_H__ +#define __UTIL_DOT_H__ + +void dlm_message_out(struct dlm_message *ms); +void dlm_message_in(struct dlm_message *ms); +void dlm_rcom_out(struct dlm_rcom *rc); +void dlm_rcom_in(struct dlm_rcom *rc); + +#endif + diff --git a/include/linux/dlm.h b/include/linux/dlm.h new file mode 100644 index 000000000000..dd324ba44d80 --- /dev/null +++ b/include/linux/dlm.h @@ -0,0 +1,312 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +#ifndef __DLM_DOT_H__ +#define __DLM_DOT_H__ + +/* + * Interface to Distributed Lock Manager (DLM) + * routines and structures to use DLM lockspaces + */ + +/* + * Lock Modes + */ + +#define DLM_LOCK_IV -1 /* invalid */ +#define DLM_LOCK_NL 0 /* null */ +#define DLM_LOCK_CR 1 /* concurrent read */ +#define DLM_LOCK_CW 2 /* concurrent write */ +#define DLM_LOCK_PR 3 /* protected read */ +#define DLM_LOCK_PW 4 /* protected write */ +#define DLM_LOCK_EX 5 /* exclusive */ + +/* + * Maximum size in bytes of a dlm_lock name + */ + +#define DLM_RESNAME_MAXLEN 64 + +/* + * Flags to dlm_lock + * + * DLM_LKF_NOQUEUE + * + * Do not queue the lock request on the wait queue if it cannot be granted + * immediately. If the lock cannot be granted because of this flag, DLM will + * either return -EAGAIN from the dlm_lock call or will return 0 from + * dlm_lock and -EAGAIN in the lock status block when the AST is executed. + * + * DLM_LKF_CANCEL + * + * Used to cancel a pending lock request or conversion. A converting lock is + * returned to its previously granted mode. + * + * DLM_LKF_CONVERT + * + * Indicates a lock conversion request. For conversions the name and namelen + * are ignored and the lock ID in the LKSB is used to identify the lock. + * + * DLM_LKF_VALBLK + * + * Requests DLM to return the current contents of the lock value block in the + * lock status block. When this flag is set in a lock conversion from PW or EX + * modes, DLM assigns the value specified in the lock status block to the lock + * value block of the lock resource. The LVB is a DLM_LVB_LEN size array + * containing application-specific information. + * + * DLM_LKF_QUECVT + * + * Force a conversion request to be queued, even if it is compatible with + * the granted modes of other locks on the same resource. + * + * DLM_LKF_IVVALBLK + * + * Invalidate the lock value block. + * + * DLM_LKF_CONVDEADLK + * + * Allows the dlm to resolve conversion deadlocks internally by demoting the + * granted mode of a converting lock to NL. The DLM_SBF_DEMOTED flag is + * returned for a conversion that's been effected by this. + * + * DLM_LKF_PERSISTENT + * + * Only relevant to locks originating in userspace. A persistent lock will not + * be removed if the process holding the lock exits. + * + * DLM_LKF_NODLKWT + * DLM_LKF_NODLCKBLK + * + * net yet implemented + * + * DLM_LKF_EXPEDITE + * + * Used only with new requests for NL mode locks. Tells the lock manager + * to grant the lock, ignoring other locks in convert and wait queues. + * + * DLM_LKF_NOQUEUEBAST + * + * Send blocking AST's before returning -EAGAIN to the caller. It is only + * used along with the NOQUEUE flag. Blocking AST's are not sent for failed + * NOQUEUE requests otherwise. + * + * DLM_LKF_HEADQUE + * + * Add a lock to the head of the convert or wait queue rather than the tail. + * + * DLM_LKF_NOORDER + * + * Disregard the standard grant order rules and grant a lock as soon as it + * is compatible with other granted locks. + * + * DLM_LKF_ORPHAN + * + * not yet implemented + * + * DLM_LKF_ALTPR + * + * If the requested mode cannot be granted immediately, try to grant the lock + * in PR mode instead. If this alternate mode is granted instead of the + * requested mode, DLM_SBF_ALTMODE is returned in the lksb. + * + * DLM_LKF_ALTCW + * + * The same as ALTPR, but the alternate mode is CW. + * + * DLM_LKF_FORCEUNLOCK + * + * Unlock the lock even if it is converting or waiting or has sublocks. + * Only really for use by the userland device.c code. + * + */ + +#define DLM_LKF_NOQUEUE 0x00000001 +#define DLM_LKF_CANCEL 0x00000002 +#define DLM_LKF_CONVERT 0x00000004 +#define DLM_LKF_VALBLK 0x00000008 +#define DLM_LKF_QUECVT 0x00000010 +#define DLM_LKF_IVVALBLK 0x00000020 +#define DLM_LKF_CONVDEADLK 0x00000040 +#define DLM_LKF_PERSISTENT 0x00000080 +#define DLM_LKF_NODLCKWT 0x00000100 +#define DLM_LKF_NODLCKBLK 0x00000200 +#define DLM_LKF_EXPEDITE 0x00000400 +#define DLM_LKF_NOQUEUEBAST 0x00000800 +#define DLM_LKF_HEADQUE 0x00001000 +#define DLM_LKF_NOORDER 0x00002000 +#define DLM_LKF_ORPHAN 0x00004000 +#define DLM_LKF_ALTPR 0x00008000 +#define DLM_LKF_ALTCW 0x00010000 +#define DLM_LKF_FORCEUNLOCK 0x00020000 + +/* + * Some return codes that are not in errno.h + */ + +#define DLM_ECANCEL 0x10001 +#define DLM_EUNLOCK 0x10002 + +typedef void dlm_lockspace_t; + +/* + * Lock range structure + */ + +struct dlm_range { + uint64_t ra_start; + uint64_t ra_end; +}; + +/* + * Lock status block + * + * Use this structure to specify the contents of the lock value block. For a + * conversion request, this structure is used to specify the lock ID of the + * lock. DLM writes the status of the lock request and the lock ID assigned + * to the request in the lock status block. + * + * sb_lkid: the returned lock ID. It is set on new (non-conversion) requests. + * It is available when dlm_lock returns. + * + * sb_lvbptr: saves or returns the contents of the lock's LVB according to rules + * shown for the DLM_LKF_VALBLK flag. + * + * sb_flags: DLM_SBF_DEMOTED is returned if in the process of promoting a lock, + * it was first demoted to NL to avoid conversion deadlock. + * DLM_SBF_VALNOTVALID is returned if the resource's LVB is marked invalid. + * + * sb_status: the returned status of the lock request set prior to AST + * execution. Possible return values: + * + * 0 if lock request was successful + * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE + * -ENOMEM if there is no memory to process request + * -EINVAL if there are invalid parameters + * -DLM_EUNLOCK if unlock request was successful + * -DLM_ECANCEL if a cancel completed successfully + */ + +#define DLM_SBF_DEMOTED 0x01 +#define DLM_SBF_VALNOTVALID 0x02 +#define DLM_SBF_ALTMODE 0x04 + +struct dlm_lksb { + int sb_status; + uint32_t sb_lkid; + char sb_flags; + char * sb_lvbptr; +}; + + +#ifdef __KERNEL__ + +#define DLM_LSFL_NODIR 0x00000001 + +/* + * dlm_new_lockspace + * + * Starts a lockspace with the given name. If the named lockspace exists in + * the cluster, the calling node joins it. + */ + +int dlm_new_lockspace(char *name, int namelen, dlm_lockspace_t **lockspace, + uint32_t flags, int lvblen); + +/* + * dlm_release_lockspace + * + * Stop a lockspace. + */ + +int dlm_release_lockspace(dlm_lockspace_t *lockspace, int force); + +/* + * dlm_lock + * + * Make an asyncronous request to acquire or convert a lock on a named + * resource. + * + * lockspace: context for the request + * mode: the requested mode of the lock (DLM_LOCK_) + * lksb: lock status block for input and async return values + * flags: input flags (DLM_LKF_) + * name: name of the resource to lock, can be binary + * namelen: the length in bytes of the resource name (MAX_RESNAME_LEN) + * parent: the lock ID of a parent lock or 0 if none + * lockast: function DLM executes when it completes processing the request + * astarg: argument passed to lockast and bast functions + * bast: function DLM executes when this lock later blocks another request + * + * Returns: + * 0 if request is successfully queued for processing + * -EINVAL if any input parameters are invalid + * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE + * -ENOMEM if there is no memory to process request + * -ENOTCONN if there is a communication error + * + * If the call to dlm_lock returns an error then the operation has failed and + * the AST routine will not be called. If dlm_lock returns 0 it is still + * possible that the lock operation will fail. The AST routine will be called + * when the locking is complete and the status is returned in the lksb. + * + * If the AST routines or parameter are passed to a conversion operation then + * they will overwrite those values that were passed to a previous dlm_lock + * call. + * + * AST routines should not block (at least not for long), but may make + * any locking calls they please. + */ + +int dlm_lock(dlm_lockspace_t *lockspace, + int mode, + struct dlm_lksb *lksb, + uint32_t flags, + void *name, + unsigned int namelen, + uint32_t parent_lkid, + void (*lockast) (void *astarg), + void *astarg, + void (*bast) (void *astarg, int mode), + struct dlm_range *range); + +/* + * dlm_unlock + * + * Asynchronously release a lock on a resource. The AST routine is called + * when the resource is successfully unlocked. + * + * lockspace: context for the request + * lkid: the lock ID as returned in the lksb + * flags: input flags (DLM_LKF_) + * lksb: if NULL the lksb parameter passed to last lock request is used + * astarg: the arg used with the completion ast for the unlock + * + * Returns: + * 0 if request is successfully queued for processing + * -EINVAL if any input parameters are invalid + * -ENOTEMPTY if the lock still has sublocks + * -EBUSY if the lock is waiting for a remote lock operation + * -ENOTCONN if there is a communication error + */ + +int dlm_unlock(dlm_lockspace_t *lockspace, + uint32_t lkid, + uint32_t flags, + struct dlm_lksb *lksb, + void *astarg); + +#endif /* __KERNEL__ */ + +#endif /* __DLM_DOT_H__ */ + diff --git a/include/linux/dlm_device.h b/include/linux/dlm_device.h new file mode 100644 index 000000000000..5e17d295544b --- /dev/null +++ b/include/linux/dlm_device.h @@ -0,0 +1,84 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ + +/* This is the device interface for dlm, most users will use a library + * interface. + */ + +#define DLM_USER_LVB_LEN 32 + +/* Version of the device interface */ +#define DLM_DEVICE_VERSION_MAJOR 3 +#define DLM_DEVICE_VERSION_MINOR 0 +#define DLM_DEVICE_VERSION_PATCH 0 + +/* struct passed to the lock write */ +struct dlm_lock_params { + __u8 mode; + __u16 flags; + __u32 lkid; + __u32 parent; + struct dlm_range range; + __u8 namelen; + void __user *castparam; + void __user *castaddr; + void __user *bastparam; + void __user *bastaddr; + struct dlm_lksb __user *lksb; + char lvb[DLM_USER_LVB_LEN]; + char name[1]; +}; + +struct dlm_lspace_params { + __u32 flags; + __u32 minor; + char name[1]; +}; + +struct dlm_write_request { + __u32 version[3]; + __u8 cmd; + + union { + struct dlm_lock_params lock; + struct dlm_lspace_params lspace; + } i; +}; + +/* struct read from the "device" fd, + consists mainly of userspace pointers for the library to use */ +struct dlm_lock_result { + __u32 length; + void __user * user_astaddr; + void __user * user_astparam; + struct dlm_lksb __user * user_lksb; + struct dlm_lksb lksb; + __u8 bast_mode; + /* Offsets may be zero if no data is present */ + __u32 lvb_offset; +}; + +/* Commands passed to the device */ +#define DLM_USER_LOCK 1 +#define DLM_USER_UNLOCK 2 +#define DLM_USER_QUERY 3 +#define DLM_USER_CREATE_LOCKSPACE 4 +#define DLM_USER_REMOVE_LOCKSPACE 5 + +/* Arbitrary length restriction */ +#define MAX_LS_NAME_LEN 64 + +/* Lockspace flags */ +#define DLM_USER_LSFLG_AUTOFREE 1 +#define DLM_USER_LSFLG_FORCEFREE 2 + |
