diff options
Diffstat (limited to 'fs/dlm/recover.c')
| -rw-r--r-- | fs/dlm/recover.c | 765 |
1 files changed, 765 insertions, 0 deletions
diff --git a/fs/dlm/recover.c b/fs/dlm/recover.c new file mode 100644 index 000000000000..a5e6d184872e --- /dev/null +++ b/fs/dlm/recover.c @@ -0,0 +1,765 @@ +/****************************************************************************** +******************************************************************************* +** +** 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() and set_locks_purged() 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 %llx", + (unsigned long long)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 recover_locks(struct dlm_rsb *r) +{ + int error = 0; + + lock_rsb(r); + + DLM_ASSERT(!r->res_recover_locks_count, dlm_dump_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_dump_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 = 0; + int big_lock_exists = 0; + 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 = 1; + + if (lkb->lkb_grmode > DLM_LOCK_CR) { + big_lock_exists = 1; + 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 = 1; + + if (lkb->lkb_grmode > DLM_LOCK_CR) { + big_lock_exists = 1; + 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; + } +} + +/* We've become the new master for this rsb and waiting/converting locks may + need to be granted in dlm_grant_after_purge() due to locks that may have + existed from a removed node. */ + +static void set_locks_purged(struct dlm_rsb *r) +{ + if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue)) + rsb_set_flag(r, RSB_LOCKS_PURGED); +} + +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); + if (rsb_flag(r, RSB_NEW_MASTER2)) + set_locks_purged(r); + recover_lvb(r); + count++; + } + rsb_clear_flag(r, RSB_RECOVER_CONVERT); + rsb_clear_flag(r, RSB_NEW_MASTER2); + 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); + } +} + |
