Remove mlog(0) from fs/ocfs2/inode.c and the masklog INODE.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

ocfs2_iget is used to get/create inode. Only iget5_locked
will give us an inode = NULL. So move this check ahead of
ocfs2_read_locked_inode so that we don't need to check
inode before we read and unlock inode. This is also helpful
for trace event(see the next patch).
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

This is the 2nd step to remove the debug info of INODE.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

As there are no such debug information in fs/ocfs2/ioctl.c,
fs/ocfs2/locks.c and fs/ocfs2/sysfile.c, ML_INODE are also
removed.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

Change all the "mlog(0," in fs/ocfs2/mmap.c to trace events.
And finally remove masklog FILE_IO.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

Remove all the "mlog(0," in fs/ocfs2/aops.c.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

Change all the "mlog(0," in fs/ocfs2/refcounttree.c to trace events.
And finally remove masklog ML_REFCOUNT.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

Since all 4 files, localalloc.c, suballoc.c, alloc.c and
resize.c, which use DISK_ALLOC are changed to trace events,
Remove masklog DISK_ALLOC totally.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

This is the 4th step to remove the debug info of DISK_ALLOC.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

This is the 3rd step to remove the debug info of DISK_ALLOC.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

This is the 2nd step to remove the debug info of DISK_ALLOC.

So this patch removes all mlog(0,...) from localalloc.c and adds
the corresponding tracepoints. Different mlogs have different
solutions.
1. Some are replaced with trace event directly.
2. Some are replaced while some new parameters are added.
3. Some are combined into one trace events.
4. Some redundant mlogs are removed.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

This is the first try of replacing debug mlog(0,...) to
trace events. Wengang has did some work in his original
patch
http://oss.oracle.com/pipermail/ocfs2-devel/2009-November/005513.html
But he didn't finished it.

So this patch removes all mlog(0,...) from alloc.c and adds
the corresponding trace events. Different mlogs have different
solutions.
1. Some are replaced with trace event directly.
2. Some are replaced and some new parameters are added since
   I think we need to know the btree owner in that case.
3. Some are combined into one trace events.
4. Some redundant mlogs are removed.
What's more, it defines some event classes so that we can use
them later.

Cc: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

About one year ago, Wengang Wang tried some first steps
to add tracepoints to ocfs2. Hiss original patch is here:
http://oss.oracle.com/pipermail/ocfs2-devel/2009-November/005512.html

But as Steven Rostedt indicated in his article
http://lwn.net/Articles/383362/, we'd better have our trace
files resides in fs/ocfs2, so I rewrited the patch using the
method Steven mentioned in that article.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NTao Ma <boyu.mt@taobao.com>

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>

The exportfs encode handle function should return the minimum required
handle size. This helps user to find out the handle size by passing 0
handle size in the first step and then redoing to the call again with
the returned handle size value.
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

all remaining callers pass LOOKUP_PARENT to it, so
flags argument can die; renamed to kern_path_parent()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Commit 2c442719 added some checks for proper
heartbeat mode when the o2cb stack is running.  Unfortunately, it didn't
take into account that a userpsace stack could be running. Fix this by only
doing the check if o2cb is in use. This patch allows userspace stacks to
mount the fs again.

Cc: stable@kernel.org
Signed-off-by: NMark Fasheh <mfasheh@suse.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

Current refcounttree codes actually didn't writeback the new pages out in
write-back mode, due to a bug of always passing a ZERO number of clusters
to 'ocfs2_cow_sync_writeback', the patch tries to pass a proper one in.
Signed-off-by: NTristan Ye <tristan.ye@oracle.com>
Cc: stable@kernel.org
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

In the rare case that INLINE_DATA, INDEX_DIR, QUOTA, XATTR features are
disabled and both the allocation of the directory inode and the allocation
of the first directory block need to relink allocation group, there need
not be enough credits reserved in a transaction. Fix the estimate.

CC: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit.  Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes.  On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions.   Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.

This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Instead of various home grown checks that might need updates for new
flags just check for any bit outside the mask of the features supported
by the filesystem.  This makes the check future proof for any newly
added flag.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This patch fixes the following kconfig error after changing
CONFIGFS_FS -> select SYSFS:

fs/sysfs/Kconfig:1:error: recursive dependency detected!
fs/sysfs/Kconfig:1:	symbol SYSFS is selected by CONFIGFS_FS
fs/configfs/Kconfig:1:	symbol CONFIGFS_FS is selected by OCFS2_FS
fs/ocfs2/Kconfig:1:	symbol OCFS2_FS depends on SYSFS
Signed-off-by: NNicholas A. Bellinger <nab@linux-iscsi.org>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: James Bottomley <James.Bottomley@suse.de>

This patch just makes ocfs2 use its UNRESERVP ioctl when we get the hole punch
flag in fallocate.  I didn't test it, but it seems simple enough.  Thanks,
Acked-by: NJan Kara <jack@suse.cz>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NJosef Bacik <josef@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

As Al Viro pointed out path resolution during Q_QUOTAON calls to quotactl
is prone to deadlocks. We hold s_umount semaphore for reading during the
path resolution and resolution itself may need to acquire the semaphore
for writing when e. g. autofs mountpoint is passed.

Solve the problem by performing the resolution before we get hold of the
superblock (and thus s_umount semaphore). The whole thing is complicated
by the fact that some filesystems (OCFS2) ignore the path argument. So to
distinguish between filesystem which want the path and which do not we
introduce new .quota_on_meta callback which does not get the path. OCFS2
then uses this callback instead of old .quota_on.

CC: Al Viro <viro@ZenIV.linux.org.uk>
CC: Christoph Hellwig <hch@lst.de>
CC: Ted Ts'o <tytso@mit.edu>
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Tristan Ye has done some refactoring against our truncate
process, so some functions like ocfs2_prepare_truncate and
ocfs2_free_truncate_context are no use and we'd better
remove them.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

In the original code, we dereferenced "nst" before checking that it was
non-NULL.  I moved the check forward and pulled the code in an indent
level.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

When CONFIG_OCFS2_FS_STATS is not enabled:

fs/ocfs2/cluster/tcp.c:1254: error: implicit declaration of function 'o2net_update_recv_stats'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc:	Mark Fasheh <mfasheh@suse.com>
Cc:	Joel Becker <joel.becker@oracle.com>
Cc:	ocfs2-devel@oss.oracle.com
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

dcache_inode_lock can be replaced with per-inode locking. Use existing
inode->i_lock for this. This is slightly non-trivial because we sometimes
need to find the inode from the dentry, which requires d_inode to be
stabilised (either with refcount or d_lock).
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page->mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

dget_locked was a shortcut to avoid the lazy lru manipulation when we already
held dcache_lock (lru manipulation was relatively cheap at that point).
However, how that the lru lock is an innermost one, we never hold it at any
caller, so the lock cost can now be avoided. We already have well working lazy
dcache LRU, so it should be fine to defer LRU manipulations to scan time.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

dcache_lock no longer protects anything. remove it.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Add a new lock, dcache_inode_lock, to protect the inode's i_dentry list
from concurrent modification. d_alias is also protected by d_lock.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Protect d_unhashed(dentry) condition with d_lock. This means keeping
DCACHE_UNHASHED bit in synch with hash manipulations.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

flush_scheduled_work() is deprecated and scheduled to be removed.

* cancel_delayed_work() + flush_schedule_work() ->
  cancel_delayed_work_sync().

* flush qs->qs_work directly on exit instead.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>