GFS2: Merge lock_dlm module into GFS2

This is the big patch that I've been working on for some time
now. There are many reasons for wanting to make this change
such as:
 o Reducing overhead by eliminating duplicated fields between structures
 o Simplifcation of the code (reduces the code size by a fair bit)
 o The locking interface is now the DLM interface itself as proposed
   some time ago.
 o Fewer lookups of glocks when processing replies from the DLM
 o Fewer memory allocations/deallocations for each glock
 o Scope to do further optimisations in the future (but this patch is
   more than big enough for now!)

Please note that (a) this patch relates to the lock_dlm module and
not the DLM itself, that is still a separate module; and (b) that
we retain the ability to build GFS2 as a standalone single node
filesystem with out requiring the DLM.

This patch needs a lot of testing, hence my keeping it I restarted
my -git tree after the last merge window. That way, this has the maximum
exposure before its merged. This is (modulo a few minor bug fixes) the
same patch that I've been posting on and off the the last three months
and its passed a number of different tests so far.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 0 insertions, 276 deletions

diff --git a/fs/gfs2/locking/dlm/mount.c b/fs/gfs2/locking/dlm/mount.c
deleted file mode 100644
index 1aa7eb6a0226..000000000000
--- a/fs/gfs2/locking/dlm/mount.c
+++ /dev/null
@@ -1,276 +0,0 @@
-/*
- * 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 version 2.
- */
-
-#include "lock_dlm.h"
-
-const struct lm_lockops gdlm_ops;
-
-
-static struct gdlm_ls *init_gdlm(lm_callback_t cb, struct gfs2_sbd *sdp,
-				 int flags, char *table_name)
-{
-	struct gdlm_ls *ls;
-	char buf[256], *p;
-
-	ls = kzalloc(sizeof(struct gdlm_ls), GFP_KERNEL);
-	if (!ls)
-		return NULL;
-
-	ls->fscb = cb;
-	ls->sdp = sdp;
-	ls->fsflags = flags;
-	spin_lock_init(&ls->async_lock);
-	INIT_LIST_HEAD(&ls->delayed);
-	INIT_LIST_HEAD(&ls->submit);
-	init_waitqueue_head(&ls->thread_wait);
-	init_waitqueue_head(&ls->wait_control);
-	ls->jid = -1;
-
-	strncpy(buf, table_name, 256);
-	buf[255] = '\0';
-
-	p = strchr(buf, ':');
-	if (!p) {
-		log_info("invalid table_name \"%s\"", table_name);
-		kfree(ls);
-		return NULL;
-	}
-	*p = '\0';
-	p++;
-
-	strncpy(ls->clustername, buf, GDLM_NAME_LEN);
-	strncpy(ls->fsname, p, GDLM_NAME_LEN);
-
-	return ls;
-}
-
-static int make_args(struct gdlm_ls *ls, char *data_arg, int *nodir)
-{
-	char data[256];
-	char *options, *x, *y;
-	int error = 0;
-
-	memset(data, 0, 256);
-	strncpy(data, data_arg, 255);
-
-	if (!strlen(data)) {
-		log_error("no mount options, (u)mount helpers not installed");
-		return -EINVAL;
-	}
-
-	for (options = data; (x = strsep(&options, ":")); ) {
-		if (!*x)
-			continue;
-
-		y = strchr(x, '=');
-		if (y)
-			*y++ = 0;
-
-		if (!strcmp(x, "jid")) {
-			if (!y) {
-				log_error("need argument to jid");
-				error = -EINVAL;
-				break;
-			}
-			sscanf(y, "%u", &ls->jid);
-
-		} else if (!strcmp(x, "first")) {
-			if (!y) {
-				log_error("need argument to first");
-				error = -EINVAL;
-				break;
-			}
-			sscanf(y, "%u", &ls->first);
-
-		} else if (!strcmp(x, "id")) {
-			if (!y) {
-				log_error("need argument to id");
-				error = -EINVAL;
-				break;
-			}
-			sscanf(y, "%u", &ls->id);
-
-		} else if (!strcmp(x, "nodir")) {
-			if (!y) {
-				log_error("need argument to nodir");
-				error = -EINVAL;
-				break;
-			}
-			sscanf(y, "%u", nodir);
-
-		} else {
-			log_error("unkonwn option: %s", x);
-			error = -EINVAL;
-			break;
-		}
-	}
-
-	return error;
-}
-
-static int gdlm_mount(char *table_name, char *host_data,
-			lm_callback_t cb, void *cb_data,
-			unsigned int min_lvb_size, int flags,
-			struct lm_lockstruct *lockstruct,
-			struct kobject *fskobj)
-{
-	struct gdlm_ls *ls;
-	int error = -ENOMEM, nodir = 0;
-
-	if (min_lvb_size > GDLM_LVB_SIZE)
-		goto out;
-
-	ls = init_gdlm(cb, cb_data, flags, table_name);
-	if (!ls)
-		goto out;
-
-	error = make_args(ls, host_data, &nodir);
-	if (error)
-		goto out;
-
-	error = gdlm_init_threads(ls);
-	if (error)
-		goto out_free;
-
-	error = gdlm_kobject_setup(ls, fskobj);
-	if (error)
-		goto out_thread;
-
-	error = dlm_new_lockspace(ls->fsname, strlen(ls->fsname),
-				  &ls->dlm_lockspace,
-				  DLM_LSFL_FS | DLM_LSFL_NEWEXCL |
-				  (nodir ? DLM_LSFL_NODIR : 0),
-				  GDLM_LVB_SIZE);
-	if (error) {
-		log_error("dlm_new_lockspace error %d", error);
-		goto out_kobj;
-	}
-
-	lockstruct->ls_jid = ls->jid;
-	lockstruct->ls_first = ls->first;
-	lockstruct->ls_lockspace = ls;
-	lockstruct->ls_ops = &gdlm_ops;
-	lockstruct->ls_flags = 0;
-	lockstruct->ls_lvb_size = GDLM_LVB_SIZE;
-	return 0;
-
-out_kobj:
-	gdlm_kobject_release(ls);
-out_thread:
-	gdlm_release_threads(ls);
-out_free:
-	kfree(ls);
-out:
-	return error;
-}
-
-static void gdlm_unmount(void *lockspace)
-{
-	struct gdlm_ls *ls = lockspace;
-
-	log_debug("unmount flags %lx", ls->flags);
-
-	/* FIXME: serialize unmount and withdraw in case they
-	   happen at once.  Also, if unmount follows withdraw,
-	   wait for withdraw to finish. */
-
-	if (test_bit(DFL_WITHDRAW, &ls->flags))
-		goto out;
-
-	gdlm_kobject_release(ls);
-	dlm_release_lockspace(ls->dlm_lockspace, 2);
-	gdlm_release_threads(ls);
-	BUG_ON(ls->all_locks_count);
-out:
-	kfree(ls);
-}
-
-static void gdlm_recovery_done(void *lockspace, unsigned int jid,
-                               unsigned int message)
-{
-	char env_jid[20];
-	char env_status[20];
-	char *envp[] = { env_jid, env_status, NULL };
-	struct gdlm_ls *ls = lockspace;
-	ls->recover_jid_done = jid;
-	ls->recover_jid_status = message;
-	sprintf(env_jid, "JID=%d", jid);
-	sprintf(env_status, "RECOVERY=%s",
-		message == LM_RD_SUCCESS ? "Done" : "Failed");
-	kobject_uevent_env(&ls->kobj, KOBJ_CHANGE, envp);
-}
-
-static void gdlm_others_may_mount(void *lockspace)
-{
-	char *message = "FIRSTMOUNT=Done";
-	char *envp[] = { message, NULL };
-	struct gdlm_ls *ls = lockspace;
-	ls->first_done = 1;
-	kobject_uevent_env(&ls->kobj, KOBJ_CHANGE, envp);
-}
-
-/* Userspace gets the offline uevent, blocks new gfs locks on
-   other mounters, and lets us know (sets WITHDRAW flag).  Then,
-   userspace leaves the mount group while we leave the lockspace. */
-
-static void gdlm_withdraw(void *lockspace)
-{
-	struct gdlm_ls *ls = lockspace;
-
-	kobject_uevent(&ls->kobj, KOBJ_OFFLINE);
-
-	wait_event_interruptible(ls->wait_control,
-				 test_bit(DFL_WITHDRAW, &ls->flags));
-
-	dlm_release_lockspace(ls->dlm_lockspace, 2);
-	gdlm_release_threads(ls);
-	gdlm_kobject_release(ls);
-}
-
-static int gdlm_plock(void *lockspace, struct lm_lockname *name,
-	       struct file *file, int cmd, struct file_lock *fl)
-{
-	struct gdlm_ls *ls = lockspace;
-	return dlm_posix_lock(ls->dlm_lockspace, name->ln_number, file, cmd, fl);
-}
-
-static int gdlm_punlock(void *lockspace, struct lm_lockname *name,
-		 struct file *file, struct file_lock *fl)
-{
-	struct gdlm_ls *ls = lockspace;
-	return dlm_posix_unlock(ls->dlm_lockspace, name->ln_number, file, fl);
-}
-
-static int gdlm_plock_get(void *lockspace, struct lm_lockname *name,
-		   struct file *file, struct file_lock *fl)
-{
-	struct gdlm_ls *ls = lockspace;
-	return dlm_posix_get(ls->dlm_lockspace, name->ln_number, file, fl);
-}
-
-const struct lm_lockops gdlm_ops = {
-	.lm_proto_name = "lock_dlm",
-	.lm_mount = gdlm_mount,
-	.lm_others_may_mount = gdlm_others_may_mount,
-	.lm_unmount = gdlm_unmount,
-	.lm_withdraw = gdlm_withdraw,
-	.lm_get_lock = gdlm_get_lock,
-	.lm_put_lock = gdlm_put_lock,
-	.lm_lock = gdlm_lock,
-	.lm_unlock = gdlm_unlock,
-	.lm_plock = gdlm_plock,
-	.lm_punlock = gdlm_punlock,
-	.lm_plock_get = gdlm_plock_get,
-	.lm_cancel = gdlm_cancel,
-	.lm_hold_lvb = gdlm_hold_lvb,
-	.lm_unhold_lvb = gdlm_unhold_lvb,
-	.lm_recovery_done = gdlm_recovery_done,
-	.lm_owner = THIS_MODULE,
-};
-