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>

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>

Print the node number of a peer node if sending it a message failed.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

In o2dlm, the master of a lock resource keeps a map of all interested
nodes.  This prevents the master from purging the resource before an
interested node can create a lock.

A race between the mastery thread and the mastery handler allowed an
interested node to discover who the master is without informing the
master directly.  This is easily fixed by holding the dlm spinlock a
little longer in the mastery handler.
Signed-off-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Patch removes trailing whitespaces.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.
Signed-off-by: NAndré Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

* remove asm/atomic.h inclusion from linux/utsname.h --
   not needed after kref conversion
 * remove linux/utsname.h inclusion from files which do not need it

NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however
due to some personality stuff it _is_ needed -- cowardly leave ELF-related
headers and files alone.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch removes struct dlm_lock_name and adds the entries directly
to struct dlm_master_list_entry. Under the new scheme, both mles that
are backed by a lockres or not, will have the name populated in mle->mname.
This allows us to get rid of code that was figuring out the location of
the mle name.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch inlines dlm_set_lockres_owner() and dlm_change_lockres_owner().
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch replaces the lockres counts that tracked the number number of
locally and remotely mastered lockres' with a current and total count. The
total count is the number of lockres' that have been created since the dlm
domain was created.

The number of locally and remotely mastered counts can be computed using
the locking_state output.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

The lifetime of a mle is limited to the duration of the lockres mastery
process. While typically this lifetime is fairly short, we have noticed
the number of mles explode under certain circumstances. This patch tracks
the number of each different types of mles and should help us determine
how best to speed up the mastery process.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

The previous patch explicitly did not indent dlm_cleanup_master_list()
so as to make the patch readable. This patch properly indents the
function.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

With this patch, the mles are stored in a hash and not a simple list.
This should improve the mle lookup time when the number of outstanding
masteries is large.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch refactors dlm_clean_master_list() so as to make it
easier to convert the mle list to a hash.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

For master mle, the name it stored in the attached lockres in struct qstr.
For block and migration mle, the name is stored inline in struct dlm_lock_name.
This patch attempts to make struct dlm_lock_name look like a struct qstr. While
we could use struct qstr, we don't because we want to avoid having to malloc
and free the lockname string as the mle's lifetime is fairly short.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch encapsulates adding and removing of the mle from the
dlm->master_list. This patch is part of the series of patches that
converts the mle list to a mle hash.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

In dlm_assert_master_handler(), if we get an incorrect assert master from a node
that, we reply with EINVAL asking the asserter to die. The problem is that an
assert is sent after so many hoops, it is invariably the node that thinks the
asserter is wrong, is actually wrong. So instead of killing the asserter, this
patch kills the assertee.

This patch papers over a race that is still being addressed.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

dlm_get_lock_resource() is supposed to return a lock resource with a proper
master. If multiple concurrent threads attempt to lookup the lockres for the
same lockid while the lock mastery in underway, one or more threads are likely
to return a lockres without a proper master.

This patch makes the threads wait in dlm_get_lock_resource() while the mastery
is underway, ensuring all threads return the lockres with a proper master.

This issue is known to be limited to users using the flock() syscall. For all
other fs operations, the ocfs2 dlmglue layer serializes the dlm op for each
lockid.

Users encountering this bug will see flock() return EINVAL and dmesg have the
following error:
ERROR: Dlm error "DLM_BADARGS" while calling dlmlock on resource <LOCKID>: bad api args
Reported-by: NColy Li <coyli@suse.de>
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch adds a new lock, dlm->tracking_lock, to protect adding/removing
lockres' to/from the dlm->tracking_list. We were previously using dlm->spinlock
for the same, but that proved inadequate as we could be freeing a lockres from
a context that did not hold that lock. As the new lock only protects this list,
we can explicitly take it when removing the lockres from the tracking list.

This bug was exposed when testing multiple processes concurrently flock() the
same file.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Patch address a racing migrate request message and an exit domain message.
Instead of blocking exit domains for the duration of the migrate, we ignore
failure to deliver that message. This is because an exiting domain should
not have any active locks and thus has no role to play in the migration.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Patch fixes a race that can result in an oops while adding a
lockres to the dlm lockres tracking list.

Bug introduced by mainline commit 29576f8b.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch helps in consolidating debugging related functions in dlmdebug.c.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch moves some mle related definitions from dlmmaster.c
to dlmcommon.h. Future patches need these definitions to dump mle
debugging information.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.beckeroracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch links all the lockres' to a tracking list in dlm_ctxt.
We will use this in an upcoming patch that will walk the entire
list and to dump the lockres states to a debugfs file.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch makes the o2dlm allocate memory for lockres, lockname and lock
structures from slabcaches rather than kmalloc. This allows us to not only
make these allocs more efficient but also allows us to track the memory being
consumed by these structures.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch renames dlm_mle_slabcache to prevent namespace clashes with fs/dlm.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

dlm_master_request_handler() forgot to put a lockres when
dlm_assert_master_worker() failed or was skipped.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Normally locks for remote nodes are freed when that node sends an UNLOCK
message to the master. The master node tags an DLM_UNLOCK_FREE_LOCK action
to do an extra put on the lock at the end.

However, there are times when the master node has to free the locks for the
remote nodes forcibly.

Two cases when this happens are:
1. When the master has migrated the lockres plus all locks to another node.
2. When the master is clearing all the locks of a dead node.

It was in the above two conditions that the dlm was missing the extra put.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

__dlm_print_one_lock_resource must be called with spin_lock
the res->spinlock. While in some cases, we use it without this
precondition and lead to the failure of assert_spin_locked.
So call dlm_print_one_lock_resource instead.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This patch makes the needlessly global dlm_do_assert_master() static.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Slab destructors were no longer supported after Christoph's
c59def9f change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

In dlm_migrate_lockres(), we check upfront whether the lockres is a
candidate for migration. This patch encapsulates that code in a separate
function so that dlm_empty_lockres() can also use it during umount. This
patch addresses the umount process spinning problem.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

__dlm_lockres_unused() expects the caller to take the lockres spinlock.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Eventhough the set refmap bit message is sent before the clear refmap
message, currently there is no guarentee that the set message will be
handled before the clear. This patch prevents the clear refmap to be
processed while the node is sending assert master messages to other
nodes. (The set refmap message is sent as a response to the assert
master request).
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This patch prevents the dlm from sending the clear refmap message
before the set refmap. We use the newly created post function handler
routine to accomplish the task.
Signed-off-by: NKurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Currently o2net allows one handler function per message type. This
patch adds the ability to call another function to be called after
the handler has returned the message to the other node.

Handlers are now given the option of returning a context (in the form of a
void **) which will be passed back into the post message handler function.
Signed-off-by: NKurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

The dlm was not waking up threads waiting on the lockres wait queue,
waiting for the lockres to be no longer be in the DLM_LOCK_RES_IN_PROGRESS
and the DLM_LOCK_RES_MIGRATING states.
Signed-off-by: NKurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This is to prevent the condition in which a previously queued
up assert master asserts after we start the migration. Now
migration ensures the workqueue is flushed before proceeding
with migrating the lock to another node. This condition is
typically encountered during parallel umounts.
Signed-off-by: NKurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>