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-rw-r--r--kernel/fs/ocfs2/dlm/dlmunlock.c698
1 files changed, 698 insertions, 0 deletions
diff --git a/kernel/fs/ocfs2/dlm/dlmunlock.c b/kernel/fs/ocfs2/dlm/dlmunlock.c
new file mode 100644
index 000000000..2e3c9dbab
--- /dev/null
+++ b/kernel/fs/ocfs2/dlm/dlmunlock.c
@@ -0,0 +1,698 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * dlmunlock.c
+ *
+ * underlying calls for unlocking locks
+ *
+ * Copyright (C) 2004 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ *
+ */
+
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/highmem.h>
+#include <linux/init.h>
+#include <linux/sysctl.h>
+#include <linux/random.h>
+#include <linux/blkdev.h>
+#include <linux/socket.h>
+#include <linux/inet.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+
+#include "cluster/heartbeat.h"
+#include "cluster/nodemanager.h"
+#include "cluster/tcp.h"
+
+#include "dlmapi.h"
+#include "dlmcommon.h"
+
+#define MLOG_MASK_PREFIX ML_DLM
+#include "cluster/masklog.h"
+
+#define DLM_UNLOCK_FREE_LOCK 0x00000001
+#define DLM_UNLOCK_CALL_AST 0x00000002
+#define DLM_UNLOCK_REMOVE_LOCK 0x00000004
+#define DLM_UNLOCK_REGRANT_LOCK 0x00000008
+#define DLM_UNLOCK_CLEAR_CONVERT_TYPE 0x00000010
+
+
+static enum dlm_status dlm_get_cancel_actions(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int *actions);
+static enum dlm_status dlm_get_unlock_actions(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int *actions);
+
+static enum dlm_status dlm_send_remote_unlock_request(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int flags,
+ u8 owner);
+
+
+/*
+ * according to the spec:
+ * http://opendlm.sourceforge.net/cvsmirror/opendlm/docs/dlmbook_final.pdf
+ *
+ * flags & LKM_CANCEL != 0: must be converting or blocked
+ * flags & LKM_CANCEL == 0: must be granted
+ *
+ * So to unlock a converting lock, you must first cancel the
+ * convert (passing LKM_CANCEL in flags), then call the unlock
+ * again (with no LKM_CANCEL in flags).
+ */
+
+
+/*
+ * locking:
+ * caller needs: none
+ * taken: res->spinlock and lock->spinlock taken and dropped
+ * held on exit: none
+ * returns: DLM_NORMAL, DLM_NOLOCKMGR, status from network
+ * all callers should have taken an extra ref on lock coming in
+ */
+static enum dlm_status dlmunlock_common(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int flags, int *call_ast,
+ int master_node)
+{
+ enum dlm_status status;
+ int actions = 0;
+ int in_use;
+ u8 owner;
+
+ mlog(0, "master_node = %d, valblk = %d\n", master_node,
+ flags & LKM_VALBLK);
+
+ if (master_node)
+ BUG_ON(res->owner != dlm->node_num);
+ else
+ BUG_ON(res->owner == dlm->node_num);
+
+ spin_lock(&dlm->ast_lock);
+ /* We want to be sure that we're not freeing a lock
+ * that still has AST's pending... */
+ in_use = !list_empty(&lock->ast_list);
+ spin_unlock(&dlm->ast_lock);
+ if (in_use && !(flags & LKM_CANCEL)) {
+ mlog(ML_ERROR, "lockres %.*s: Someone is calling dlmunlock "
+ "while waiting for an ast!", res->lockname.len,
+ res->lockname.name);
+ return DLM_BADPARAM;
+ }
+
+ spin_lock(&res->spinlock);
+ if (res->state & DLM_LOCK_RES_IN_PROGRESS) {
+ if (master_node && !(flags & LKM_CANCEL)) {
+ mlog(ML_ERROR, "lockres in progress!\n");
+ spin_unlock(&res->spinlock);
+ return DLM_FORWARD;
+ }
+ /* ok for this to sleep if not in a network handler */
+ __dlm_wait_on_lockres(res);
+ res->state |= DLM_LOCK_RES_IN_PROGRESS;
+ }
+ spin_lock(&lock->spinlock);
+
+ if (res->state & DLM_LOCK_RES_RECOVERING) {
+ status = DLM_RECOVERING;
+ goto leave;
+ }
+
+ if (res->state & DLM_LOCK_RES_MIGRATING) {
+ status = DLM_MIGRATING;
+ goto leave;
+ }
+
+ /* see above for what the spec says about
+ * LKM_CANCEL and the lock queue state */
+ if (flags & LKM_CANCEL)
+ status = dlm_get_cancel_actions(dlm, res, lock, lksb, &actions);
+ else
+ status = dlm_get_unlock_actions(dlm, res, lock, lksb, &actions);
+
+ if (status != DLM_NORMAL && (status != DLM_CANCELGRANT || !master_node))
+ goto leave;
+
+ /* By now this has been masked out of cancel requests. */
+ if (flags & LKM_VALBLK) {
+ /* make the final update to the lvb */
+ if (master_node)
+ memcpy(res->lvb, lksb->lvb, DLM_LVB_LEN);
+ else
+ flags |= LKM_PUT_LVB; /* let the send function
+ * handle it. */
+ }
+
+ if (!master_node) {
+ owner = res->owner;
+ /* drop locks and send message */
+ if (flags & LKM_CANCEL)
+ lock->cancel_pending = 1;
+ else
+ lock->unlock_pending = 1;
+ spin_unlock(&lock->spinlock);
+ spin_unlock(&res->spinlock);
+ status = dlm_send_remote_unlock_request(dlm, res, lock, lksb,
+ flags, owner);
+ spin_lock(&res->spinlock);
+ spin_lock(&lock->spinlock);
+ /* if the master told us the lock was already granted,
+ * let the ast handle all of these actions */
+ if (status == DLM_CANCELGRANT) {
+ actions &= ~(DLM_UNLOCK_REMOVE_LOCK|
+ DLM_UNLOCK_REGRANT_LOCK|
+ DLM_UNLOCK_CLEAR_CONVERT_TYPE);
+ } else if (status == DLM_RECOVERING ||
+ status == DLM_MIGRATING ||
+ status == DLM_FORWARD ||
+ status == DLM_NOLOCKMGR
+ ) {
+ /* must clear the actions because this unlock
+ * is about to be retried. cannot free or do
+ * any list manipulation. */
+ mlog(0, "%s:%.*s: clearing actions, %s\n",
+ dlm->name, res->lockname.len,
+ res->lockname.name,
+ status==DLM_RECOVERING?"recovering":
+ (status==DLM_MIGRATING?"migrating":
+ (status == DLM_FORWARD ? "forward" :
+ "nolockmanager")));
+ actions = 0;
+ }
+ if (flags & LKM_CANCEL)
+ lock->cancel_pending = 0;
+ else
+ lock->unlock_pending = 0;
+
+ }
+
+ /* get an extra ref on lock. if we are just switching
+ * lists here, we dont want the lock to go away. */
+ dlm_lock_get(lock);
+
+ if (actions & DLM_UNLOCK_REMOVE_LOCK) {
+ list_del_init(&lock->list);
+ dlm_lock_put(lock);
+ }
+ if (actions & DLM_UNLOCK_REGRANT_LOCK) {
+ dlm_lock_get(lock);
+ list_add_tail(&lock->list, &res->granted);
+ }
+ if (actions & DLM_UNLOCK_CLEAR_CONVERT_TYPE) {
+ mlog(0, "clearing convert_type at %smaster node\n",
+ master_node ? "" : "non-");
+ lock->ml.convert_type = LKM_IVMODE;
+ }
+
+ /* remove the extra ref on lock */
+ dlm_lock_put(lock);
+
+leave:
+ res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
+ if (!dlm_lock_on_list(&res->converting, lock))
+ BUG_ON(lock->ml.convert_type != LKM_IVMODE);
+ else
+ BUG_ON(lock->ml.convert_type == LKM_IVMODE);
+ spin_unlock(&lock->spinlock);
+ spin_unlock(&res->spinlock);
+ wake_up(&res->wq);
+
+ /* let the caller's final dlm_lock_put handle the actual kfree */
+ if (actions & DLM_UNLOCK_FREE_LOCK) {
+ /* this should always be coupled with list removal */
+ BUG_ON(!(actions & DLM_UNLOCK_REMOVE_LOCK));
+ mlog(0, "lock %u:%llu should be gone now! refs=%d\n",
+ dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
+ dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
+ atomic_read(&lock->lock_refs.refcount)-1);
+ dlm_lock_put(lock);
+ }
+ if (actions & DLM_UNLOCK_CALL_AST)
+ *call_ast = 1;
+
+ /* if cancel or unlock succeeded, lvb work is done */
+ if (status == DLM_NORMAL)
+ lksb->flags &= ~(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB);
+
+ return status;
+}
+
+void dlm_commit_pending_unlock(struct dlm_lock_resource *res,
+ struct dlm_lock *lock)
+{
+ /* leave DLM_LKSB_PUT_LVB on the lksb so any final
+ * update of the lvb will be sent to the new master */
+ list_del_init(&lock->list);
+}
+
+void dlm_commit_pending_cancel(struct dlm_lock_resource *res,
+ struct dlm_lock *lock)
+{
+ list_move_tail(&lock->list, &res->granted);
+ lock->ml.convert_type = LKM_IVMODE;
+}
+
+
+static inline enum dlm_status dlmunlock_master(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int flags,
+ int *call_ast)
+{
+ return dlmunlock_common(dlm, res, lock, lksb, flags, call_ast, 1);
+}
+
+static inline enum dlm_status dlmunlock_remote(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int flags, int *call_ast)
+{
+ return dlmunlock_common(dlm, res, lock, lksb, flags, call_ast, 0);
+}
+
+/*
+ * locking:
+ * caller needs: none
+ * taken: none
+ * held on exit: none
+ * returns: DLM_NORMAL, DLM_NOLOCKMGR, status from network
+ */
+static enum dlm_status dlm_send_remote_unlock_request(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int flags,
+ u8 owner)
+{
+ struct dlm_unlock_lock unlock;
+ int tmpret;
+ enum dlm_status ret;
+ int status = 0;
+ struct kvec vec[2];
+ size_t veclen = 1;
+
+ mlog(0, "%.*s\n", res->lockname.len, res->lockname.name);
+
+ if (owner == dlm->node_num) {
+ /* ended up trying to contact ourself. this means
+ * that the lockres had been remote but became local
+ * via a migration. just retry it, now as local */
+ mlog(0, "%s:%.*s: this node became the master due to a "
+ "migration, re-evaluate now\n", dlm->name,
+ res->lockname.len, res->lockname.name);
+ return DLM_FORWARD;
+ }
+
+ memset(&unlock, 0, sizeof(unlock));
+ unlock.node_idx = dlm->node_num;
+ unlock.flags = cpu_to_be32(flags);
+ unlock.cookie = lock->ml.cookie;
+ unlock.namelen = res->lockname.len;
+ memcpy(unlock.name, res->lockname.name, unlock.namelen);
+
+ vec[0].iov_len = sizeof(struct dlm_unlock_lock);
+ vec[0].iov_base = &unlock;
+
+ if (flags & LKM_PUT_LVB) {
+ /* extra data to send if we are updating lvb */
+ vec[1].iov_len = DLM_LVB_LEN;
+ vec[1].iov_base = lock->lksb->lvb;
+ veclen++;
+ }
+
+ tmpret = o2net_send_message_vec(DLM_UNLOCK_LOCK_MSG, dlm->key,
+ vec, veclen, owner, &status);
+ if (tmpret >= 0) {
+ // successfully sent and received
+ if (status == DLM_FORWARD)
+ mlog(0, "master was in-progress. retry\n");
+ ret = status;
+ } else {
+ mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
+ "node %u\n", tmpret, DLM_UNLOCK_LOCK_MSG, dlm->key, owner);
+ if (dlm_is_host_down(tmpret)) {
+ /* NOTE: this seems strange, but it is what we want.
+ * when the master goes down during a cancel or
+ * unlock, the recovery code completes the operation
+ * as if the master had not died, then passes the
+ * updated state to the recovery master. this thread
+ * just needs to finish out the operation and call
+ * the unlockast. */
+ if (dlm_is_node_dead(dlm, owner))
+ ret = DLM_NORMAL;
+ else
+ ret = DLM_NOLOCKMGR;
+ } else {
+ /* something bad. this will BUG in ocfs2 */
+ ret = dlm_err_to_dlm_status(tmpret);
+ }
+ }
+
+ return ret;
+}
+
+/*
+ * locking:
+ * caller needs: none
+ * taken: takes and drops res->spinlock
+ * held on exit: none
+ * returns: DLM_NORMAL, DLM_BADARGS, DLM_IVLOCKID,
+ * return value from dlmunlock_master
+ */
+int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data,
+ void **ret_data)
+{
+ struct dlm_ctxt *dlm = data;
+ struct dlm_unlock_lock *unlock = (struct dlm_unlock_lock *)msg->buf;
+ struct dlm_lock_resource *res = NULL;
+ struct dlm_lock *lock = NULL;
+ enum dlm_status status = DLM_NORMAL;
+ int found = 0, i;
+ struct dlm_lockstatus *lksb = NULL;
+ int ignore;
+ u32 flags;
+ struct list_head *queue;
+
+ flags = be32_to_cpu(unlock->flags);
+
+ if (flags & LKM_GET_LVB) {
+ mlog(ML_ERROR, "bad args! GET_LVB specified on unlock!\n");
+ return DLM_BADARGS;
+ }
+
+ if ((flags & (LKM_PUT_LVB|LKM_CANCEL)) == (LKM_PUT_LVB|LKM_CANCEL)) {
+ mlog(ML_ERROR, "bad args! cannot modify lvb on a CANCEL "
+ "request!\n");
+ return DLM_BADARGS;
+ }
+
+ if (unlock->namelen > DLM_LOCKID_NAME_MAX) {
+ mlog(ML_ERROR, "Invalid name length in unlock handler!\n");
+ return DLM_IVBUFLEN;
+ }
+
+ if (!dlm_grab(dlm))
+ return DLM_REJECTED;
+
+ mlog_bug_on_msg(!dlm_domain_fully_joined(dlm),
+ "Domain %s not fully joined!\n", dlm->name);
+
+ mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" : "none");
+
+ res = dlm_lookup_lockres(dlm, unlock->name, unlock->namelen);
+ if (!res) {
+ /* We assume here that a no lock resource simply means
+ * it was migrated away and destroyed before the other
+ * node could detect it. */
+ mlog(0, "returning DLM_FORWARD -- res no longer exists\n");
+ status = DLM_FORWARD;
+ goto not_found;
+ }
+
+ queue=&res->granted;
+ found = 0;
+ spin_lock(&res->spinlock);
+ if (res->state & DLM_LOCK_RES_RECOVERING) {
+ spin_unlock(&res->spinlock);
+ mlog(0, "returning DLM_RECOVERING\n");
+ status = DLM_RECOVERING;
+ goto leave;
+ }
+
+ if (res->state & DLM_LOCK_RES_MIGRATING) {
+ spin_unlock(&res->spinlock);
+ mlog(0, "returning DLM_MIGRATING\n");
+ status = DLM_MIGRATING;
+ goto leave;
+ }
+
+ if (res->owner != dlm->node_num) {
+ spin_unlock(&res->spinlock);
+ mlog(0, "returning DLM_FORWARD -- not master\n");
+ status = DLM_FORWARD;
+ goto leave;
+ }
+
+ for (i=0; i<3; i++) {
+ list_for_each_entry(lock, queue, list) {
+ if (lock->ml.cookie == unlock->cookie &&
+ lock->ml.node == unlock->node_idx) {
+ dlm_lock_get(lock);
+ found = 1;
+ break;
+ }
+ }
+ if (found)
+ break;
+ /* scan granted -> converting -> blocked queues */
+ queue++;
+ }
+ spin_unlock(&res->spinlock);
+ if (!found) {
+ status = DLM_IVLOCKID;
+ goto not_found;
+ }
+
+ /* lock was found on queue */
+ lksb = lock->lksb;
+ if (flags & (LKM_VALBLK|LKM_PUT_LVB) &&
+ lock->ml.type != LKM_EXMODE)
+ flags &= ~(LKM_VALBLK|LKM_PUT_LVB);
+
+ /* unlockast only called on originating node */
+ if (flags & LKM_PUT_LVB) {
+ lksb->flags |= DLM_LKSB_PUT_LVB;
+ memcpy(&lksb->lvb[0], &unlock->lvb[0], DLM_LVB_LEN);
+ }
+
+ /* if this is in-progress, propagate the DLM_FORWARD
+ * all the way back out */
+ status = dlmunlock_master(dlm, res, lock, lksb, flags, &ignore);
+ if (status == DLM_FORWARD)
+ mlog(0, "lockres is in progress\n");
+
+ if (flags & LKM_PUT_LVB)
+ lksb->flags &= ~DLM_LKSB_PUT_LVB;
+
+ dlm_lockres_calc_usage(dlm, res);
+ dlm_kick_thread(dlm, res);
+
+not_found:
+ if (!found)
+ mlog(ML_ERROR, "failed to find lock to unlock! "
+ "cookie=%u:%llu\n",
+ dlm_get_lock_cookie_node(be64_to_cpu(unlock->cookie)),
+ dlm_get_lock_cookie_seq(be64_to_cpu(unlock->cookie)));
+ else
+ dlm_lock_put(lock);
+
+leave:
+ if (res)
+ dlm_lockres_put(res);
+
+ dlm_put(dlm);
+
+ return status;
+}
+
+
+static enum dlm_status dlm_get_cancel_actions(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int *actions)
+{
+ enum dlm_status status;
+
+ if (dlm_lock_on_list(&res->blocked, lock)) {
+ /* cancel this outright */
+ status = DLM_NORMAL;
+ *actions = (DLM_UNLOCK_CALL_AST |
+ DLM_UNLOCK_REMOVE_LOCK);
+ } else if (dlm_lock_on_list(&res->converting, lock)) {
+ /* cancel the request, put back on granted */
+ status = DLM_NORMAL;
+ *actions = (DLM_UNLOCK_CALL_AST |
+ DLM_UNLOCK_REMOVE_LOCK |
+ DLM_UNLOCK_REGRANT_LOCK |
+ DLM_UNLOCK_CLEAR_CONVERT_TYPE);
+ } else if (dlm_lock_on_list(&res->granted, lock)) {
+ /* too late, already granted. */
+ status = DLM_CANCELGRANT;
+ *actions = DLM_UNLOCK_CALL_AST;
+ } else {
+ mlog(ML_ERROR, "lock to cancel is not on any list!\n");
+ status = DLM_IVLOCKID;
+ *actions = 0;
+ }
+ return status;
+}
+
+static enum dlm_status dlm_get_unlock_actions(struct dlm_ctxt *dlm,
+ struct dlm_lock_resource *res,
+ struct dlm_lock *lock,
+ struct dlm_lockstatus *lksb,
+ int *actions)
+{
+ enum dlm_status status;
+
+ /* unlock request */
+ if (!dlm_lock_on_list(&res->granted, lock)) {
+ status = DLM_DENIED;
+ dlm_error(status);
+ *actions = 0;
+ } else {
+ /* unlock granted lock */
+ status = DLM_NORMAL;
+ *actions = (DLM_UNLOCK_FREE_LOCK |
+ DLM_UNLOCK_CALL_AST |
+ DLM_UNLOCK_REMOVE_LOCK);
+ }
+ return status;
+}
+
+/* there seems to be no point in doing this async
+ * since (even for the remote case) there is really
+ * no work to queue up... so just do it and fire the
+ * unlockast by hand when done... */
+enum dlm_status dlmunlock(struct dlm_ctxt *dlm, struct dlm_lockstatus *lksb,
+ int flags, dlm_astunlockfunc_t *unlockast, void *data)
+{
+ enum dlm_status status;
+ struct dlm_lock_resource *res;
+ struct dlm_lock *lock = NULL;
+ int call_ast, is_master;
+
+ if (!lksb) {
+ dlm_error(DLM_BADARGS);
+ return DLM_BADARGS;
+ }
+
+ if (flags & ~(LKM_CANCEL | LKM_VALBLK | LKM_INVVALBLK)) {
+ dlm_error(DLM_BADPARAM);
+ return DLM_BADPARAM;
+ }
+
+ if ((flags & (LKM_VALBLK | LKM_CANCEL)) == (LKM_VALBLK | LKM_CANCEL)) {
+ mlog(0, "VALBLK given with CANCEL: ignoring VALBLK\n");
+ flags &= ~LKM_VALBLK;
+ }
+
+ if (!lksb->lockid || !lksb->lockid->lockres) {
+ dlm_error(DLM_BADPARAM);
+ return DLM_BADPARAM;
+ }
+
+ lock = lksb->lockid;
+ BUG_ON(!lock);
+ dlm_lock_get(lock);
+
+ res = lock->lockres;
+ BUG_ON(!res);
+ dlm_lockres_get(res);
+retry:
+ call_ast = 0;
+ /* need to retry up here because owner may have changed */
+ mlog(0, "lock=%p res=%p\n", lock, res);
+
+ spin_lock(&res->spinlock);
+ is_master = (res->owner == dlm->node_num);
+ if (flags & LKM_VALBLK && lock->ml.type != LKM_EXMODE)
+ flags &= ~LKM_VALBLK;
+ spin_unlock(&res->spinlock);
+
+ if (is_master) {
+ status = dlmunlock_master(dlm, res, lock, lksb, flags,
+ &call_ast);
+ mlog(0, "done calling dlmunlock_master: returned %d, "
+ "call_ast is %d\n", status, call_ast);
+ } else {
+ status = dlmunlock_remote(dlm, res, lock, lksb, flags,
+ &call_ast);
+ mlog(0, "done calling dlmunlock_remote: returned %d, "
+ "call_ast is %d\n", status, call_ast);
+ }
+
+ if (status == DLM_RECOVERING ||
+ status == DLM_MIGRATING ||
+ status == DLM_FORWARD ||
+ status == DLM_NOLOCKMGR) {
+
+ /* We want to go away for a tiny bit to allow recovery
+ * / migration to complete on this resource. I don't
+ * know of any wait queue we could sleep on as this
+ * may be happening on another node. Perhaps the
+ * proper solution is to queue up requests on the
+ * other end? */
+
+ /* do we want to yield(); ?? */
+ msleep(50);
+
+ mlog(0, "retrying unlock due to pending recovery/"
+ "migration/in-progress/reconnect\n");
+ goto retry;
+ }
+
+ if (call_ast) {
+ mlog(0, "calling unlockast(%p, %d)\n", data, status);
+ if (is_master) {
+ /* it is possible that there is one last bast
+ * pending. make sure it is flushed, then
+ * call the unlockast.
+ * not an issue if this is a mastered remotely,
+ * since this lock has been removed from the
+ * lockres queues and cannot be found. */
+ dlm_kick_thread(dlm, NULL);
+ wait_event(dlm->ast_wq,
+ dlm_lock_basts_flushed(dlm, lock));
+ }
+ (*unlockast)(data, status);
+ }
+
+ if (status == DLM_CANCELGRANT)
+ status = DLM_NORMAL;
+
+ if (status == DLM_NORMAL) {
+ mlog(0, "kicking the thread\n");
+ dlm_kick_thread(dlm, res);
+ } else
+ dlm_error(status);
+
+ dlm_lockres_calc_usage(dlm, res);
+ dlm_lockres_put(res);
+ dlm_lock_put(lock);
+
+ mlog(0, "returning status=%d!\n", status);
+ return status;
+}
+EXPORT_SYMBOL_GPL(dlmunlock);
+