dlm_finish_local_lockres_recovery() needed a facelift.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>

o2dlm messages needed a facelift.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>

During dlm domain shutdown, o2dlm has to free all the lock resources. Ones that
have no locks and references are freed. Ones that have locks and/or references
are migrated to another node.

The first task in migration is finding a target. Currently we scan the lock
resource and find one node that either has a lock or a reference. This is not
very efficient in a parallel umount case as we might end up migrating the
lock resource to a node which itself may have to migrate it to a third node.

The patch scans the dlm->exit_domain_map to ensure the target node is not
leaving the domain. If no valid target node is found, o2dlm does not migrate
the resource but instead waits for the unlock and deref messages that will
allow it to free the resource.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

This patch adds a new dlm message DLM_BEGIN_EXIT_DOMAIN_MSG and ups the dlm
protocol to 1.2.

o2dlm sends this new message in dlm_unregister_domain() to mark the beginning
of the exit domain. This message is sent to all nodes in the domain.

Currently o2dlm has no way of informing other nodes of its impending exit.
This information is useful as the other nodes could disregard the exiting
node in certain operations. For example, in resource migration. If two or
more nodes were umounting in parallel, it would be more efficient if o2dlm
were to choose a non-exiting node to be the new master node rather than an
exiting one.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Reviewed-by: NMark Fasheh <mfasheh@suse.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

Patch cleans up the gunk added by commit 388c4bcb.
dlm_is_lockres_migrateable() now returns 1 if lockresource is deemed
migrateable and 0 if not.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

During resource migration, if the target node were to die, the thread doing
the migration spins until the target node is not removed from the domain map.
This patch slows the spin by making the thread wait for the recovery to kick in.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

Patch fixes a bug in the o2dlm protocol negotiation in that it is using
the builtin version rather than the negotiated version during the domain
join. This causes join errors when a node having kernel >= 2.6.37 joins
a cluster with nodes having kernels < 2.6.37.

This only affects the o2cb cluster stack.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Reported-by: NJacek Stepniewski <Jacek.Stepniewski@agora.pl>
Acked-by: NMark Fasheh <mfasheh@suse.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Replace EXTRA_CFLAGS with ccflags-y. And change ntfs-objs to ntfs-y
for cleaner conditional inclusion.
Signed-off-by: Nmatt mooney <mfm@muteddisk.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

In dlm_query_region_handler(), move the kmalloc outside the spinlock.
This allows us to use GFP_KERNEL instead of GFP_ATOMIC.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

mlog_exit is used to record the exit status of a function.
But because it is added in so many functions, if we enable it,
the system logs get filled up quickly and cause too much I/O.
So actually no one can open it for a production system or even
for a test.

This patch just try to remove it or change it. So:
1. if all the error paths already use mlog_errno, it is just removed.
   Otherwise, it will be replaced by mlog_errno.
2. if it is used to print some return value, it is replaced with
   mlog(0,...).
mlog_exit_ptr is changed to mlog(0.
All those mlog(0,...) will be replaced with trace events later.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

ENTRY is used to record the entry of a function.
But because it is added in so many functions, if we enable it,
the system logs get filled up quickly and cause too much I/O.
So actually no one can open it for a production system or even
for a test.

So for mlog_entry_void, we just remove it.
for mlog_entry(...), we replace it with mlog(0,...), and they
will be replace by trace event later.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

In o2dlm, the enumerated message values are part of the protocol.
The patch hard codes each value so as to reduce the chance of an editing
error causing a protocol mismatch.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Patch makes use of task_pid_nr(). Also removes the null check before calling
debugfs_remove().
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Remove struct debug_buffer in dlmdebug.c/h.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch adds support for pinning o2hb regions in configfs. Pinning disallows
a region to be cleanly stopped as long as it has an active dependent user
(read o2dlm).

In local heartbeat mode, the region uuid matching the domain name is pinned as
long as the o2dlm domain is active.

In global heartbeat mode, all regions are pinned as long as there is atleast
one dependent user and the region count is 3 or less. All regions are unpinned
if the number of dependent users is zero or region count is greater than 3.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Make existing convertion precedent over new lock. It makes o2dlm locking more
like fair locking.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Add the domain name and the resource name in the mlogs.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

o2dlm was not migrating resources with zero locks because it assumed that that
resource would get purged by dlm_thread. However, some usage patterns involve
creating and dropping locks at a high rate leading to the migrate thread seeing
zero locks but the purge thread seeing an active reference. When this happens,
the dlm_thread cannot purge the resource and the migrate thread sees no reason
to migrate that resource. The spell is broken when the migrate thread catches
the resource with a lock.

The fix is to make the migrate thread also consider the reference map.

This usage pattern can be triggered by userspace on userdlm locks and flocks.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

coccinelle check scripts/coccinelle/locks/call_kern.cocci found that
in fs/ocfs2/dlm/dlmdomain.c an allocation with GFP_KERNEL is done
with locks held:

dlm_query_region_handler
  spin_lock(dlm_domain_lock)
    dlm_match_regions
      kmalloc(GFP_KERNEL)

Change it to GFP_ATOMIC.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
CC: Joel Becker <joel.becker@oracle.com>
CC: Mark Fasheh <mfasheh@suse.com>
CC: ocfs2-devel@oss.oracle.com

--
Exists in v2.6.37-rc1 and current linux-next.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

dlm protocol 1.1. activates messages DLM_QUERY_REGION and DLM_QUERY_NODEINFO
that are a must for global heartbeat.

It also activates o2hb_global_heartbeat_active().
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>

ocfs2/dlm: Add message DLM_QUERY_NODEINFO

Adds new dlm message DLM_QUERY_NODEINFO that sends the attributes of all
registered nodes. This message is sent if the negotiated dlm protocol is
1.1 or higher. If the information of the joining node does not match
that of any existing nodes, the join domain request is rejected.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>

ocfs2/dlm: Add message DLM_QUERY_REGION

Adds new dlm message DLM_QUERY_REGION that sends the names of all active
heartbeat regions. This message is only sent in the global heartbeat
mode. If the regions in the joining node do not fully match the ones in
the active nodes, the join domain request is rejected.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>

ocfs2/dlm: Expose dlm_protocol in dlm_state

Add dlm_protocol to the list of info shown by the debugfs file, dlm_state.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>

While umounting, a block mle doesn't get freed if dlm is shutdown after
master request is received but before assert master. This results in unclean
shutdown of dlm domain.

This patch frees all mles that lie around after other nodes were notified about
exiting the dlm and marking dlm state as leaving. Only block mles are expected
to be around, so we log ERROR for other mles but still free them.
Signed-off-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch tries to handle the case in which list 'dlm->tracking_list' is
empty, to avoid accessing an invalid pointer. It fixes the following oops:

http://oss.oracle.com/bugzilla/show_bug.cgi?id=1287Signed-off-by: NTristan Ye <tristan.ye@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

When we need to take both dlm_domain_lock and dlm->spinlock, we should take
them in order of: dlm_domain_lock then dlm->spinlock.

There is pathes disobey this order. That is calling dlm_lockres_put() with
dlm->spinlock held in dlm_run_purge_list. dlm_lockres_put() calls dlm_put() at
the ref and dlm_put() locks on dlm_domain_lock.

Fix:
Don't grab/put the dlm when the initialising/releasing lockres.
That grab is not required because we don't call dlm_unregister_domain()
based on refcount.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Cc: stable@kernel.org
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

In the following situation, there remains an incorrect bit in refmap on the
recovery master. Finally the recovery master will fail at purging the lockres
due to the incorrect bit in refmap.

1) node A has no interest on lockres A any longer, so it is purging it.
2) the owner of lockres A is node B, so node A is sending de-ref message
to node B.
3) at this time, node B crashed. node C becomes the recovery master. it recovers
lockres A(because the master is the dead node B).
4) node A migrated lockres A to node C with a refbit there.
5) node A failed to send de-ref message to node B because it crashed. The failure
is ignored. no other action is done for lockres A any more.

For mormal, re-send the deref message to it to recovery master can fix it. Well,
ignoring the failure of deref to the original master and not recovering the lockres
to recovery master has the same effect. And the later is simpler.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Acked-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
Cc: stable@kernel.org
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch fixes two problems in dlm_run_purgelist

1. If a lockres is found to be in use, dlm_run_purgelist keeps trying to purge
the same lockres instead of trying the next lockres.

2. When a lockres is found unused, dlm_run_purgelist releases lockres spinlock
before setting DLM_LOCK_RES_DROPPING_REF and calls dlm_purge_lockres.
spinlock is reacquired but in this window lockres can get reused. This leads
to BUG.

This patch modifies dlm_run_purgelist to skip lockres if it's in use and purge
 next lockres. It also sets DLM_LOCK_RES_DROPPING_REF before releasing the
lockres spinlock protecting it from getting reused.
Signed-off-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
Acked-by: NSunil Mushran <sunil.mushran@oracle.com>
Cc: stable@kernel.org
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

When we have to take both dlm->master_lock and lockres->spinlock,
take them in order

lockres->spinlock and then dlm->master_lock.

The patch fixes a violation of the rule.
We can simply move taking dlm->master_lock to where we have dropped res->spinlock
since when we access res->state and free mle memory we don't need master_lock's
protection.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Cc: stable@kernel.org
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Signed-off-by: NJoe Perches <joe@perches.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

For migration, we are waiting for DLM_LOCK_RES_MIGRATING flag to be set
before sending DLM_MIG_LOCKRES_MSG message to the target. We are using
dlm_migration_can_proceed() for that purpose.  However, if the node is
down, dlm_migration_can_proceed() will also return "go ahead".  In this
rare case, the DLM_LOCK_RES_MIGRATING flag might not be set yet. Remove
the BUG_ON() that trips over this condition.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This function is only called from one place and it's like this:
	dlm_register_domain(conn->cc_name, dlm_key, &fs_version);

The "conn->cc_name" is 64 characters long.  If strlen(conn->cc_name)
were equal to O2NM_MAX_NAME_LEN (64) that would be a bug because
strlen() doesn't count the NULL character.

In fact, if you look how O2NM_MAX_NAME_LEN is used, it mostly describes
64 character buffers.  The only exception is nd_name from struct
o2nm_node.

Anyway I looked into it and in this case the domain string comes from
osb->uuid_str in ocfs2_setup_osb_uuid().  That's 32 characters and NULL
which easily fits into O2NM_MAX_NAME_LEN.  This patch doesn't change how
the code works, but I think it makes the code a little cleaner.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

dlm->recovery_map is defined as
	unsigned long recovery_map[BITS_TO_LONGS(O2NM_MAX_NODES)];

We should treat O2NM_MAX_NODES as the bit map size in bits.
This patches fixes a bit operation that takes O2NM_MAX_NODES + 1 as bitmap size.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Add a spin_unlock missing on the error path.  Unlock as in the other code
that leads to the leave label.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E1;
@@

* spin_lock(E1,...);
  <+... when != E1
  if (...) {
    ... when != E1
*   return ...;
  }
  ...+>
* spin_unlock(E1,...);
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Currently we process a dirty lockres with the lockres->spinlock taken. While
during the process, we may need to lock on dlm->ast_lock. This breaks the
dependency of dlm->ast_lock(lock first) and lockres->spinlock(lock second).

This patch fixes the problem.
Since we can't release lockres->spinlock, we have to take dlm->ast_lock
just before taking the lockres->spinlock and release it after lockres->spinlock
is released. And use __dlm_queue_bast()/__dlm_queue_ast(), the nolock version,
in dlm_shuffle_lists(). There are no too many locks on a lockres, so there is no
performance harm.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Use kstrdup when the goal of an allocation is copy a string into the
allocated region.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to;
expression flag,E1,E2;
statement S;
@@

-  to = kmalloc(strlen(from) + 1,flag);
+  to = kstrdup(from, flag);
   ... when != \(from = E1 \| to = E1 \)
   if (to==NULL || ...) S
   ... when != \(from = E2 \| to = E2 \)
-  strcpy(to, from);
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Drop cast on the result of kmalloc and similar functions.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
@@

- (T *)
  (\(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|
   kmem_cache_alloc_node\|kmalloc_node\|kzalloc_node\)(...))
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Lockres hash size of 16KB is far too small for large filesystems (where we
have hundreds of thousands of lock resources stored in the table).
This patch increases it to 128KB.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>