Commit Graph

342 Commits

Author SHA1 Message Date
Joseph Qi 012572d4fc ocfs2/dlm: fix deadlock when dispatch assert master
The order of the following three spinlocks should be:
dlm_domain_lock < dlm_ctxt->spinlock < dlm_lock_resource->spinlock

But dlm_dispatch_assert_master() is called while holding
dlm_ctxt->spinlock and dlm_lock_resource->spinlock, and then it calls
dlm_grab() which will take dlm_domain_lock.

Once another thread (for example, dlm_query_join_handler) has already
taken dlm_domain_lock, and tries to take dlm_ctxt->spinlock deadlock
happens.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: "Junxiao Bi" <junxiao.bi@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-22 15:09:53 -07:00
Andrew Morton e527b22c3f revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each"
Revert commit f83c7b5e9f ("ocfs2/dlm: use list_for_each_entry instead
of list_for_each").

list_for_each_entry() will dereference its `pos' argument, which can be
NULL in dlm_process_recovery_data().

Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Reported-by: Fengguang Wu <fengguang.wu@gmail.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-11 15:21:34 -07:00
Yiwen Jiang f57a22ddec ocfs2: avoid access invalid address when read o2dlm debug messages
The following case will lead to a lockres is freed but is still in use.

cat /sys/kernel/debug/o2dlm/locking_state	dlm_thread
lockres_seq_start
    -> lock dlm->track_lock
    -> get resA
                                                resA->refs decrease to 0,
                                                call dlm_lockres_release,
                                                and wait for "cat" unlock.
Although resA->refs is already set to 0,
increase resA->refs, and then unlock
                                                lock dlm->track_lock
                                                    -> list_del_init()
                                                    -> unlock
                                                    -> free resA

In such a race case, invalid address access may occurs.  So we should
delete list res->tracking before resA->refs decrease to 0.

Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Norton.Zhu 72f6fe1fe5 ocfs2: optimize error handling in dlm_request_join
Currently error handling in dlm_request_join is a little obscure, so
optimize it to promote readability.

If packet.code is invalid, reset it to JOIN_DISALLOW to keep it
meaningful.  It only influences the log printing.

Signed-off-by: Norton.Zhu <norton.zhu@huawei.com>
Cc: Srinivas Eeda <srinivas.eeda@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Joseph Qi f83c7b5e9f ocfs2/dlm: use list_for_each_entry instead of list_for_each
Use list_for_each_entry instead of list_for_each to simplify code.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Joseph Qi 0e3d9eafb8 ocfs2: remove unneeded code in dlm_register_domain_handlers
The last goto statement is unneeded, so remove it.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Joseph Qi cdd09f49cb ocfs2: fix BUG when o2hb_register_callback fails
In dlm_register_domain_handlers, if o2hb_register_callback fails, it
will call dlm_unregister_domain_handlers to unregister.  This will
trigger the BUG_ON in o2hb_unregister_callback because hc_magic is 0.
So we should call o2hb_setup_callback to initialize hc first.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Joseph Qi 345dc681bd ocfs2/dlm: cleanup unused function __dlm_wait_on_lockres_flags_set
__dlm_wait_on_lockres_flags_set() is declared but not implemented and
used.  So remove it.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-24 17:49:39 -07:00
Junxiao Bi b1432a2a35 ocfs2: dlm: fix race between purge and get lock resource
There is a race window in dlm_get_lock_resource(), which may return a
lock resource which has been purged.  This will cause the process to
hang forever in dlmlock() as the ast msg can't be handled due to its
lock resource not existing.

    dlm_get_lock_resource {
        ...
        spin_lock(&dlm->spinlock);
        tmpres = __dlm_lookup_lockres_full(dlm, lockid, namelen, hash);
        if (tmpres) {
             spin_unlock(&dlm->spinlock);
             >>>>>>>> race window, dlm_run_purge_list() may run and purge
                              the lock resource
             spin_lock(&tmpres->spinlock);
             ...
             spin_unlock(&tmpres->spinlock);
        }
    }

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-05-05 17:10:11 -07:00
Srinivas Eeda 99b8874e79 o2dlm: fix NULL pointer dereference in o2dlm_blocking_ast_wrapper
A tiny race between BAST and unlock message causes the NULL dereference.

A node sends an unlock request to master and receives a response.  Before
processing the response it receives a BAST from the master.  Since both
requests are processed by different threads it creates a race.  While the
BAST is being processed, lock can get freed by unlock code.

This patch makes bast to return immediately if lock is found but unlock is
pending.  The code should handle this race.  We also have to fix master
node to skip sending BAST after receiving unlock message.

Below is the crash stack

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
    IP: o2dlm_blocking_ast_wrapper+0xd/0x16
    dlm_do_local_bast+0x8e/0x97 [ocfs2_dlm]
    dlm_proxy_ast_handler+0x838/0x87e [ocfs2_dlm]
    o2net_process_message+0x395/0x5b8 [ocfs2_nodemanager]
    o2net_rx_until_empty+0x762/0x90d [ocfs2_nodemanager]
    worker_thread+0x14d/0x1ed

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10 14:30:30 -08:00
Rickard Strandqvist 95671c63d5 ocfs2: dlm: dlmdomain: remove unused function
Remove dlm_joined() that is not used anywhere.

This was partially found by using a static code analysis program called
cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10 14:30:29 -08:00
alex chen 79c83ea1aa ocfs2: fix snprintf format specifier in dlmdebug.c
Use snprintf format specifier "%lu" instead of "%ld" for argument of type
'unsigned long'.

Signed-off-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10 14:30:29 -08:00
Xue jiufei b934beaf4b ocfs2/dlm: add missing dlm_lock_put() when recovery master down
When the recovery master is down, the owner of $RECOVERY calls
dlm_do_local_recovery_cleanup() to prune any $RECOVERY entries for dead
nodes.  The lock is in the granted list and the refcount must be 2.  We
should put twice to remove this lock.  Otherwise, it will lead to a memory
leak.

Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Reported-by: yangwenfang <vicky.yangwenfang@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10 14:30:28 -08:00
Joseph Qi eb4f73b4ca ocfs2: remove bogus check in dlm_process_recovery_data
In dlm_process_recovery_data, only when dlm_new_lock failed the ret will
be set to -ENOMEM.  And in this case, newlock is definitely NULL.  So
test newlock is meaningless, remove it.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-08 15:10:51 -08:00
Joseph Qi 1e58958160 ocfs2/dlm: fix race between dispatched_work and dlm_lockres_grab_inflight_worker
Commit ac4fef4d23 ("ocfs2/dlm: do not purge lockres that is queued for
assert master") may have the following possible race case:

  dlm_dispatch_assert_master       dlm_wq
  ========================================================================
  queue_work(dlm->quedlm_worker,
      &dlm->dispatched_work);
                                 dispatch work,
                                 dlm_lockres_drop_inflight_worker
                                 *BUG_ON(res->inflight_assert_workers == 0)*
  dlm_lockres_grab_inflight_worker
  inflight_assert_workers++

So ensure inflight_assert_workers to be increased first.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Xue jiufei <xuejiufei@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-18 19:08:11 -08:00
Dan Carpenter b3e3e5af60 ocfs2: remove unneeded NULL check
In commit 1faf289454 ("ocfs2_dlm: disallow a domain join if node maps
mismatch") we introduced a new earlier NULL check so this one is not
needed.  Also static checkers complain because we dereference it first
and then check for NULL.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:04 -08:00
Srinivas Eeda cb79662bc2 ocfs2: o2dlm: fix a race between purge and master query
Node A sends master query request to node B which is the master.  At this
time lockres happens to be on purgelist.  dlm_master_request_handler gets
the dlm spinlock, finds the resource and releases the dlm spin lock.
Right at this dlm_thread on this node could purge the lockres.
dlm_master_request_handler can then acquire lockres spinlock and reply to
Node A that node B is the master even though lockres on node B is purged.

The above scenario will now make node A falsely think node B is the master
which is inconsistent.  Further if another node C tries to master the same
resource, every node will respond they are not the master.  Node C then
masters the resource and sends assert master to all nodes.  This will now
make node A crash with the following message.

dlm_assert_master_handler:1831 ERROR: DIE! Mastery assert from 9, but current
owner is 10!

Signed-off-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com>
Tested-by: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:03 -08:00
Joseph Qi f08736bd6c ocfs2/dlm: let sender retry if dlm_dispatch_assert_master failed with -ENOMEM
Do not BUG() if GFP_ATOMIC allocation fails in dlm_dispatch_assert_master.
Instead, return -ENOMEM to the sender and then retry.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Alex Chen <alex.chen@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:03 -08:00
Joseph Qi 70e82a12db ocfs2: fix deadlock between o2hb thread and o2net_wq
The following case may lead to o2net_wq and o2hb thread deadlock on
o2hb_callback_sem.
Currently there are 2 nodes say N1, N2 in the cluster. And N2 down, at
the same time, N3 tries to join the cluster. So N1 will handle node
down (N2) and join (N3) simultaneously.
    o2hb                               o2net_wq
    ->o2hb_do_disk_heartbeat
    ->o2hb_check_slot
    ->o2hb_run_event_list
    ->o2hb_fire_callbacks
    ->down_write(&o2hb_callback_sem)
    ->o2net_hb_node_down_cb
    ->flush_workqueue(o2net_wq)
                                       ->o2net_process_message
                                       ->dlm_query_join_handler
                                       ->o2hb_check_node_heartbeating
                                       ->o2hb_fill_node_map
                                       ->down_read(&o2hb_callback_sem)

No need to take o2hb_callback_sem in dlm_query_join_handler,
o2hb_live_lock is enough to protect live node map.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: xMark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: jiangyiwen <jiangyiwen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:25:47 -04:00
Rob Jones 8f9ac03232 fs/ocfs2/dlm/dlmdebug.c: use seq_open_private() not seq_open()
Reduce boilerplate code by using seq_open_private() instead of seq_open()

Signed-off-by: Rob Jones <rob.jones@codethink.co.uk>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:25:47 -04:00
Xue jiufei 6ae075485e ocfs2: remove unused code in dlm_new_lockres()
Remove the branch that free res->lockname.name because the condition
is never satisfied when jump to label error.

Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:25:47 -04:00
alex chen 9a7e6b5a0a ocfs2/dlm: call dlm_lockres_put without resource spinlock
dlm_lockres_put() should be called without &res->spinlock, otherwise a
deadlock case may happen.

spin_lock(&res->spinlock)
...
dlm_lockres_put
  ->dlm_lockres_release
    ->dlm_print_one_lock_resource
      ->spin_lock(&res->spinlock)

Signed-off-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:25:47 -04:00
Joseph Qi 190a7721ac ocfs2/dlm: refactor error handling in dlm_alloc_ctxt
Refactoring error handling in dlm_alloc_ctxt to simplify code.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Alex Chen <alex.chen@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:25:46 -04:00
alex chen 55dacd22db ocfs2/dlm: should put mle when goto kill in dlm_assert_master_handler
In dlm_assert_master_handler, the mle is get in dlm_find_mle, should be
put when goto kill, otherwise, this mle will never be released.

Signed-off-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: joyce.xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-02 16:28:44 -07:00
Joseph Qi 5760a97c71 ocfs2/dlm: do not get resource spinlock if lockres is new
There is a deadlock case which reported by Guozhonghua:
  https://oss.oracle.com/pipermail/ocfs2-devel/2014-September/010079.html

This case is caused by &res->spinlock and &dlm->master_lock
misordering in different threads.

It was introduced by commit 8d400b81cc ("ocfs2/dlm: Clean up refmap
helpers").  Since lockres is new, it doesn't not require the
&res->spinlock.  So remove it.

Fixes: 8d400b81cc ("ocfs2/dlm: Clean up refmap helpers")
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: joyce.xue <xuejiufei@huawei.com>
Reported-by: Guozhonghua <guozhonghua@h3c.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-26 08:10:34 -07:00
Tariq Saeed bba1cb17d9 ocfs2: race between umount and unfinished remastering during recovery
Orabug: 19074140

When umount is issued during recovery on the new master that has not
finished remastering locks, it triggers BUG() in
dlm_send_mig_lockres_msg().  Here is the situation:

 1) node A has a lock on resource X mastered by node B.

 2) node B dies ->  node A sets recovering flag for res X

 3) Node C becomes the new master for resources owned by the
    dead node and is remastering locks of the dead node but
    has not finished the remastering process yet.

 4) umount is issued on node C.

 5) During processing of umount, ignoring unfished recovery,
    node C attempts to migrate resource X to node A.

 6) node A finds res X in DLM_LOCK_RES_RECOVERING state, considers
    it a logic error and sends back -EFAULT.

 7) node C asserts BUG() upon seeing EFAULT resp from node B.

Fix is to delay migrating res X till remastering is finished at which
point recovering flag will be cleared on both A and C.

Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:13 -07:00
Xue jiufei 7567c14883 ocfs2: remove conversion of total_backoff in dlm_join_domain()
The unit of total_backoff is msecs not jiffies, so no need to do the
conversion.  Otherwise, the join timeout is not 90 sec.

Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:13 -07:00
Xue jiufei ac4fef4d23 ocfs2/dlm: do not purge lockres that is queued for assert master
When workqueue is delayed, it may occur that a lockres is purged while it
is still queued for master assert.  it may trigger BUG() as follows.

N1                                         N2
dlm_get_lockres()
->dlm_do_master_requery
                                  is the master of lockres,
                                  so queue assert_master work

                                  dlm_thread() start running
                                  and purge the lockres

                                  dlm_assert_master_worker()
                                  send assert master message
                                  to other nodes
receiving the assert_master
message, set master to N2

dlmlock_remote() send create_lock message to N2, but receive DLM_IVLOCKID,
if it is RECOVERY lockres, it triggers the BUG().

Another BUG() is triggered when N3 become the new master and send
assert_master to N1, N1 will trigger the BUG() because owner doesn't
match.  So we should not purge lockres when it is queued for assert
master.

Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-23 16:47:45 -07:00
jiangyiwen b9aaac5a6b ocfs2: do not return DLM_MIGRATE_RESPONSE_MASTERY_REF to avoid endless,loop during umount
The following case may lead to endless loop during umount.

node A         node B               node C       node D
umount volume,
migrate lockres1
to B
                                                 want to lock lockres1,
                                                 send
                                                 MASTER_REQUEST_MSG
                                                 to C
                                    init block mle
               send
               MIGRATE_REQUEST_MSG
               to C
                                    find a block
                                    mle, and then
                                    return
                                    DLM_MIGRATE_RESPONSE_MASTERY_REF
                                    to B
               set C in refmap
                                    umount successfully
               try to umount, endless
               loop occurs when migrate
               lockres1 since C is in
               refmap

So we can fix this endless loop case by only returning
DLM_MIGRATE_RESPONSE_MASTERY_REF if it has a mastery mle when receiving
MIGRATE_REQUEST_MSG.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: jiangyiwen <jiangyiwen@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Xue jiufei <xuejiufei@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-23 16:47:45 -07:00
Xue jiufei a270c6d3c0 ocfs2/dlm: fix misuse of list_move_tail() in dlm_run_purge_list()
When a lockres in purge list but is still in use, it should be moved to
the tail of purge list.  dlm_thread will continue to check next lockres in
purge list.  However, code list_move_tail(&dlm->purge_list,
&lockres->purge) will do *no* movements, so dlm_thread will purge the same
lockres in this loop again and again.  If it is in use for a long time,
other lockres will not be processed.

Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-23 16:47:45 -07:00
Tariq Saeed 27bf6305cf ocfs2: fix deadlock when two nodes are converting same lock from PR to EX and idletimeout closes conn
Orabug: 18639535

Two node cluster and both nodes hold a lock at PR level and both want to
convert to EX at the same time.  Master node 1 has sent BAST and then
closes the connection due to idletime out.  Node 0 receives BAST, sends
unlock req with cancel flag but gets error -ENOTCONN.  The problem is
this error is ignored in dlm_send_remote_unlock_request() on the
**incorrect** assumption that the master is dead.  See NOTE in comment
why it returns DLM_NORMAL.  Upon getting DLM_NORMAL, node 0 proceeds to
sends convert (without cancel flg) which fails with -ENOTCONN.  waits 5
sec and resends.

This time gets DLM_IVLOCKID from the master since lock not found in
grant, it had been moved to converting queue in response to conv PR->EX
req.  No way out.

Node 1 (master)				Node 0
==============				======

  lock mode PR				PR

  convert PR -> EX
  mv grant -> convert and que BAST
  ...
                     <-------- convert PR -> EX
  convert que looks like this: ((node 1, PR -> EX) (node 0, PR -> EX))
  ...
                        BAST (want PR -> NL)
                     ------------------>
  ...
  idle timout, conn closed
                                ...
                                In response to BAST,
                                sends unlock with cancel convert flag
                                gets -ENOTCONN. Ignores and
                                sends remote convert request
                                gets -ENOTCONN, waits 5 Sec, retries
  ...
  reconnects
                   <----------------- convert req goes through on next try
  does not find lock on grant que
                   status DLM_IVLOCKID
                   ------------------>
  ...

No way out.  Fix is to keep retrying unlock with cancel flag until it
succeeds or the master dies.

Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-23 16:47:45 -07:00
Xue jiufei e72db989e1 ocfs2: remove some unused code
dlm_recovery_ctxt.received is unused.

ocfs2_should_refresh_lock_res() can only return 0 or 1, so the error
handling code in ocfs2_super_lock() is unneeded.

Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:53:55 -07:00
Xue jiufei 01c6222f87 ocfs2/dlm: disallow node joining when recovery is on going
We found a race situation when dlm recovery and node joining occurs
simultaneously if the network state is bad.

N1                                      N4

start joining dlm and send
query join to all live nodes
                            set joining node to N1, return OK
send query join to other
live nodes and it may take
a while

call dlm_send_join_assert()
to send assert join message
when N2 is down, so keep
trying to send message to N2
until find N2 is down

send assert join message to
N3, but connection is down
with N3, so it may take a
while
                            become the recovery master for N2
                            and send begin reco message to other
                            nodes in domain map but no N1
connection with N3 is rebuild,
then send assert join to N4
                            call dlm_assert_joined_handler(),
                            add N1 to domain_map

                            dlm recovery done, send finalize message
                            to nodes in domain map, including N1
receiving finalize message,
trigger the BUG() because
recovery master mismatch.

Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:53:54 -07:00
Xue jiufei 6718cb5e0e ocfs2/dlm: fix possible convert=sion deadlock
We found there is a conversion deadlock when the owner of lockres
happened to crash before send DLM_PROXY_AST_MSG for a downconverting
lock.  The situation is as follows:

Node1                            Node2                  Node3
                           the owner of lockresA
lock_1 granted at EX mode
and call ocfs2_cluster_unlock
to decrease ex_holders.
                                                 converting lock_3 from
                                                 NL to EX
                           send DLM_PROXY_AST_MSG
                           to Node1, asking Node 1
                           to downconvert.
receiving DLM_PROXY_AST_MSG,
thread ocfs2dc send
DLM_CONVERT_LOCK_MSG
to Node2 to downconvert
lock_1(EX->NL).
                           lock_1 can be granted and
                           put it into pending_asts
                           list, return DLM_NORMAL.
                           then something happened
                           and Node2 crashed.
received DLM_NORMAL, waiting
for DLM_PROXY_AST_MSG.
                                               selected as the recovery
                                               master, receving migrate
                                               lock from Node1, queue
                                               lock_1 to the tail of
                                               converting list.

After dlm recovery, converting list in the master of lockresA(Node3)
will be: converting list head <-> lock_3(NL->EX) <->lock_1(EX<->NL).
Requested mode of lock_3 is not compatible with the granted mode of
lock_1, so it can not be granted.  and lock_1 can not downconvert
because covnerting queue is strictly FIFO.  So a deadlock is created.
We think function dlm_process_recovery_data() should queue_ast for
lock_1 or alter the order of lock_1 and lock_3, so dlm_thread can
process lock_1 first.  And if there are multiple downconverting locks,
they must convert form PR to NL, so no need to sort them.

Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:53:54 -07:00
Fabian Frederick 1a5c4e2a0e ocfs2: remove NULL assignments on static
Static values are automatically initialized to NULL.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:53:53 -07:00
Joseph Qi 66db6cfd49 ocfs2: fix double kmem_cache_destroy in dlm_init
In dlm_init, if create dlm_lockname_cache failed in
dlm_init_master_caches, it will destroy dlm_lockres_cache which created
before twice.  And this will cause system die when loading modules.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-05-23 09:37:30 -07:00
Zhonghua Guo a35ad97cd4 ocfs2: fix deadlock risk when kmalloc failed in dlm_query_region_handler
In dlm_query_region_handler(), once kmalloc failed, it will unlock
dlm_domain_lock without lock first, then deadlock happens.

Signed-off-by: Zhonghua Guo <guozhonghua@h3c.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Tested-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:55 -07:00
Junxiao Bi ded2cf7141 ocfs2: dlm: fix recovery hung
There is a race window in dlm_do_recovery() between dlm_remaster_locks()
and dlm_reset_recovery() when the recovery master nearly finish the
recovery process for a dead node.  After the master sends FINALIZE_RECO
message in dlm_remaster_locks(), another node may become the recovery
master for another dead node, and then send the BEGIN_RECO message to
all the nodes included the old master, in the handler of this message
dlm_begin_reco_handler() of old master, dlm->reco.dead_node and
dlm->reco.new_master will be set to the second dead node and the new
master, then in dlm_reset_recovery(), these two variables will be reset
to default value.  This will cause new recovery master can not finish
the recovery process and hung, at last the whole cluster will hung for
recovery.

old recovery master:                                 new recovery master:
dlm_remaster_locks()
                                                  become recovery master for
                                                  another dead node.
                                                  dlm_send_begin_reco_message()
dlm_begin_reco_handler()
{
 if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
  return -EAGAIN;
 }
 dlm_set_reco_master(dlm, br->node_idx);
 dlm_set_reco_dead_node(dlm, br->dead_node);
}
dlm_reset_recovery()
{
 dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
}
                                                  will hang in dlm_remaster_locks() for
                                                  request dlm locks info

Before send FINALIZE_RECO message, recovery master should set
DLM_RECO_STATE_FINALIZE for itself and clear it after the recovery done,
this can break the race windows as the BEGIN_RECO messages will not be
handled before DLM_RECO_STATE_FINALIZE flag is cleared.

A similar race may happen between new recovery master and normal node
which is in dlm_finalize_reco_handler(), also fix it.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:54 -07:00
Junxiao Bi 34aa8dac48 ocfs2: dlm: fix lock migration crash
This issue was introduced by commit 800deef3f6 ("ocfs2: use
list_for_each_entry where benefical") in 2007 where it replaced
list_for_each with list_for_each_entry.  The variable "lock" will point
to invalid data if "tmpq" list is empty and a panic will be triggered
due to this.  Sunil advised reverting it back, but the old version was
also not right.  At the end of the outer for loop, that
list_for_each_entry will also set "lock" to an invalid data, then in the
next loop, if the "tmpq" list is empty, "lock" will be an stale invalid
data and cause the panic.  So reverting the list_for_each back and reset
"lock" to NULL to fix this issue.

Another concern is that this seemes can not happen because the "tmpq"
list should not be empty.  Let me describe how.

old lock resource owner(node 1):                                  migratation target(node 2):
image there's lockres with a EX lock from node 2 in
granted list, a NR lock from node x with convert_type
EX in converting list.
dlm_empty_lockres() {
 dlm_pick_migration_target() {
   pick node 2 as target as its lock is the first one
   in granted list.
 }
 dlm_migrate_lockres() {
   dlm_mark_lockres_migrating() {
     res->state |= DLM_LOCK_RES_BLOCK_DIRTY;
     wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res));
	 //after the above code, we can not dirty lockres any more,
     // so dlm_thread shuffle list will not run
                                                                   downconvert lock from EX to NR
                                                                   upconvert lock from NR to EX
<<< migration may schedule out here, then
<<< node 2 send down convert request to convert type from EX to
<<< NR, then send up convert request to convert type from NR to
<<< EX, at this time, lockres granted list is empty, and two locks
<<< in the converting list, node x up convert lock followed by
<<< node 2 up convert lock.

	 // will set lockres RES_MIGRATING flag, the following
	 // lock/unlock can not run
     dlm_lockres_release_ast(dlm, res);
   }

   dlm_send_one_lockres()
                                                                 dlm_process_recovery_data()
                                                                   for (i=0; i<mres->num_locks; i++)
                                                                     if (ml->node == dlm->node_num)
                                                                       for (j = DLM_GRANTED_LIST; j <= DLM_BLOCKED_LIST; j++) {
                                                                        list_for_each_entry(lock, tmpq, list)
                                                                        if (lock) break; <<< lock is invalid as grant list is empty.
                                                                       }
                                                                       if (lock->ml.node != ml->node)
                                                                         BUG() >>> crash here
 }

I see the above locks status from a vmcore of our internal bug.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:54 -07:00
Zongxun Wang 181a9a043b ocfs2: fix null pointer dereference when access dlm_state before launching dlm thread
When mounting an ocfs2 volume, it will firstly generate a file
/sys/kernel/debug/o2dlm/<uuid>/dlm_state, and then launch the dlm thread.
So the following situation will cause a null pointer dereference.
dlm_debug_init -> access file dlm_state which will call dlm_state_print ->
dlm_launch_thread

Move dlm_debug_init after dlm_launch_thread and dlm_launch_recovery_thread
can fix this issue.

Signed-off-by: Zongxun Wang <wangzongxun@huawei.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:53 -07:00
Goldwyn Rodrigues ff8fb33522 ocfs2: remove versioning information
The versioning information is confusing for end-users.  The numbers are
stuck at 1.5.0 when the tools version have moved to 1.8.2.  Remove the
versioning system in the OCFS2 modules and let the kernel version be the
guide to debug issues.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Acked-by: Sunil Mushran <sunil.mushran@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00
Junxiao Bi 728b98059a ocfs2: break useless while loop
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:01 +09:00
Xue jiufei fae477b6f0 ocfs2: delay migration when the lockres is in migration state
We trigger a bug in __dlm_lockres_reserve_ast() when we parallel umount 4
nodes.  The situation is as follows:

1) Node A migrate all lockres it owned(eg.  lockres A) to other nodes
   say node B when it umounts.

2) Receiving MIG_LOCKRES message from A, Node B masters the lockres A
   with DLM_LOCK_RES_MIGRATING state set.

3) Then we umount ocfs2 on node B.  It also should migrate lockres A to
   another node, say node C.  But now, DLM_LOCK_RES_MIGRATING state of
   lockers A is not cleared.  Node B triggered the BUG on lockres with
   state DLM_LOCK_RES_MIGRATING.

Signed-off-by: Xuejiufei <xuejiufei@huawei.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Tariq Saeed <tariq.x.saeed@oracle.com>
Cc: Srinivas Eeda <srinivas.eeda@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:01 +09:00
Xue jiufei 750e3c6581 ocfs2: skip locks in the blocked list
A parallel umount on 4 nodes triggered a bug in
dlm_process_recovery_date().  Here's the situation:

Receiving MIG_LOCKRES message, A node processes the locks in migratable
lockres.  It copys lvb from migratable lockres when processing the first
valid lock.

If there is a lock in the blocked list with the EX level, it triggers the
BUG.  Since valid lvbs are set when locks are granted with EX or PR
levels, locks in the blocked list cannot have valid lvbs.  Therefore I
think we should skip the locks in the blocked list.

Signed-off-by: Xuejiufei <xuejiufei@huawei.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:01 +09:00
Xue jiufei 69b2bd16d9 ocfs2/dlm: force clean refmap when doing local cleanup
dlm_do_local_recovery_cleanup() should force clean refmap if the owner of
lockres is UNKNOWN.  Otherwise node may hang when umounting filesystems.
Here's the situation:

	Node1                                    Node2
dlmlock()
  -> dlm_get_lock_resource()
send DLM_MASTER_REQUEST_MSG to
other nodes.

                                       trying to master this lockres,
                                       return MAYBE.

selected as the master of lockresA,
set mle->master to Node1,
and do assert_master,
send DLM_ASSERT_MASTER_MSG to Node2.
                                       Node 2 has interest on lockresA
                                       and return
                                       DLM_ASSERT_RESPONSE_MASTERY_REF
                                       then something happened and
                                       Node2 crashed.

Receiving DLM_ASSERT_RESPONSE_MASTERY_REF, set Node2 into refmap, and keep
sending DLM_ASSERT_MASTER_MSG to other nodes

o2hb found node2 down, calling dlm_hb_node_down() -->
dlm_do_local_recovery_cleanup() the master of lockresA is still UNKNOWN,
no need to call dlm_free_dead_locks().

Set the master of lockresA to Node1, but Node2 stills remains in refmap.

When Node1 umount, it found that the refmap of lockresA is not empty and
attempted to migrate it to Node2, But Node2 is already down, so umount
hang, trying to migrate lockresA again and again.

Signed-off-by: joyce <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:56:49 -07:00
Dong Fang df53cd3b70 ocfs2: use list_for_each_entry() instead of list_for_each()
[dan.carpenter@oracle.com: fix up some NULL dereference bugs]
Signed-off-by: Dong Fang <yp.fangdong@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jeff Liu <jeff.liu@oracle.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:56:36 -07:00
Xue jiufei 98ac9125c5 ocfs2: dlm_request_all_locks() should deal with the status sent from target node
dlm_request_all_locks() should deal with the status sent from target node
if DLM_LOCK_REQUEST_MSG is sent successfully, or recovery master will fall
into endless loop, waiting for other nodes to send locks and
DLM_RECO_DATA_DONE_MSG to me.

        NodeA                                  NodeB
                                     selected as recovery master
                                     dlm_remaster_locks()
                                     ->dlm_request_all_locks()
                                     send DLM_LOCK_REQUEST_MSG to nodeA

It happened that NodeA cannot alloc memory when it processes this
message.  dlm_request_all_locks_handler() do not queue
dlm_request_all_locks_worker and returns -ENOMEM.  It will never send
locks and DLM_RECO_DATA_DONE_MSG to NodeB.

                                    NodeB do not deal with the status
                                    sent from nodeA, and will fall in
                                    endless loop waiting for the
                                    recovery state of NodeA to be
                                    changed.

Signed-off-by: joyce <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Jeff Liu <jeff.liu@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:56:31 -07:00
Xue jiufei 096b2ef83c ocfs2: dlmlock_master() should return DLM_NORMAL after adding lock to blocked list
dlmlock_master() returns DLM_RECOVERING/DLM_MIGRATING/ DLM_FORWAR after
adding lock to blocked list if lockres has the state
DLM_LOCK_RES_RECOVERING/DLM_LOCK_RES_MIGRATING/ DLM_LOCK_RES_IN_PROGRESS.
so it will retry in dlmlock().  And this may cause dlm_thread fall into an
infinite loop

	Thread1                                  dlm_thread

  calls dlm_lock->dlmlock_master,
  if lockresA is in state
  DLM_LOCK_RES_RECOVERING, calls
  __dlm_wait_on_lockres() and waits
  until others threads clear this
  state;

  If cannot grant this lock,
  adding lock to blocked list,
  and return DLM_RECOVERING;

                                        Grant this lock and move it to
                                        grant list;

  After a while, retry and
  calls list_add_tail(), adding lock
  to blocked list again.

Granted and blocked list of this lockres will become the following
conditions:

    lock_res->granted.next = dlm_lock->list_head;
    lock_res->blocked.next = dlm_lock->list_head;
    dlm_lock->list_head.next = dlm_lock_resource->blocked;

When dlm_thread traverses the granted list, it will fall into an endless
loop, checking dlm_lock.list_head, dlm_lock->list_head.next
(i.e.lock_res->blocked), lock_res->blocked.next(i.e.dlm_lock.list_head
again) .....

Signed-off-by: joyce <xuejiufei@huawei.com>
Reviewed-by: jensen <shencanquan@huawei.com>
Cc: Jeff Liu <jeff.liu@oracle.com>
Acked-by: Sunil Mushran <sunil.mushran@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:24 -07:00
Xue jiufei 40c7f2eaf5 ocfs2: add missing dlm_put() in dlm_begin_reco_handler()
dlm_begin_reco_handler() returns without putting dlm when dlm recovery
state is DLM_RECO_STATE_FINALIZE.

Signed-off-by: joyce <xuejiufei@huawei.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:23 -07:00
Joseph Qi 22ab9014bf fs/ocfs2/dlm/dlmrecovery.c:dlm_request_all_locks(): ret should be int instead of enum
In dlm_request_all_locks, ret is type enum.  But o2net_send_message
returns a type int value.  Then it will never run into the following
error branch.  So we should change the ret type from enum to int.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: Sunil Mushran <sunil.mushran@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:23 -07:00