xfs: log new intent items created as part of finishing recovered intent items

During a code inspection, I found a serious bug in the log intent item
recovery code when an intent item cannot complete

xfs: log new intent items created as part of finishing recovered intent items

During a code inspection, I found a serious bug in the log intent item
recovery code when an intent item cannot complete all the work and
decides to requeue itself to get that done. When this happens, the
item recovery creates a new incore deferred op representing the
remaining work and attaches it to the transaction that it allocated. At
the end of _item_recover, it moves the entire chain of deferred ops to
the dummy parent_tp that xlog_recover_process_intents passed to it, but
fail to log a new intent item for the remaining work before committing
the transaction for the single unit of work.

xlog_finish_defer_ops logs those new intent items once recovery has
finished dealing with the intent items that it recovered, but this isn't
sufficient. If the log is forced to disk after a recovered log item
decides to requeue itself and the system goes down before we call
xlog_finish_defer_ops, the second log recovery will never see the new
intent item and therefore has no idea that there was more work to do.
It will finish recovery leaving the filesystem in a corrupted state.

The same logic applies to /any/ deferred ops added during intent item
recovery, not just the one handling the remaining work.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

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xfs: use ordered buffers to initialize dquot buffers during quotacheck

While QAing the new xfs_repair quotacheck code, I uncovered a quota
corruption bug resulting from a bad interaction between dqu

xfs: use ordered buffers to initialize dquot buffers during quotacheck

While QAing the new xfs_repair quotacheck code, I uncovered a quota
corruption bug resulting from a bad interaction between dquot buffer
initialization and quotacheck. The bug can be reproduced with the
following sequence:

# mkfs.xfs -f /dev/sdf
# mount /dev/sdf /opt -o usrquota
# su nobody -s /bin/bash -c 'touch /opt/barf'
# sync
# xfs_quota -x -c 'report -ahi' /opt
User quota on /opt (/dev/sdf)
Inodes
User ID Used Soft Hard Warn/Grace
---------- ---------------------------------
root 3 0 0 00 [------]
nobody 1 0 0 00 [------]

# xfs_io -x -c 'shutdown' /opt
# umount /opt
# mount /dev/sdf /opt -o usrquota
# touch /opt/man2
# xfs_quota -x -c 'report -ahi' /opt
User quota on /opt (/dev/sdf)
Inodes
User ID Used Soft Hard Warn/Grace
---------- ---------------------------------
root 1 0 0 00 [------]
nobody 1 0 0 00 [------]

# umount /opt

Notice how the initial quotacheck set the root dquot icount to 3
(rootino, rbmino, rsumino), but after shutdown -> remount -> recovery,
xfs_quota reports that the root dquot has only 1 icount. We haven't
deleted anything from the filesystem, which means that quota is now
under-counting. This behavior is not limited to icount or the root
dquot, but this is the shortest reproducer.

I traced the cause of this discrepancy to the way that we handle ondisk
dquot updates during quotacheck vs. regular fs activity. Normally, when
we allocate a disk block for a dquot, we log the buffer as a regular
(dquot) buffer. Subsequent updates to the dquots backed by that block
are done via separate dquot log item updates, which means that they
depend on the logged buffer update being written to disk before the
dquot items. Because individual dquots have their own LSN fields, that
initial dquot buffer must always be recovered.

However, the story changes for quotacheck, which can cause dquot block
allocations but persists the final dquot counter values via a delwri
list. Because recovery doesn't gate dquot buffer replay on an LSN, this
means that the initial dquot buffer can be replayed over the (newer)
contents that were delwritten at the end of quotacheck. In effect, this
re-initializes the dquot counters after they've been updated. If the
log does not contain any other dquot items to recover, the obsolete
dquot contents will not be corrected by log recovery.

Because quotacheck uses a transaction to log the setting of the CHKD
flags in the superblock, we skip quotacheck during the second mount
call, which allows the incorrect icount to remain.

Fix this by changing the ondisk dquot initialization function to use
ordered buffers to write out fresh dquot blocks if it detects that we're
running quotacheck. If the system goes down before quotacheck can
complete, the CHKD flags will not be set in the superblock and the next
mount will run quotacheck again, which can fix uninitialized dquot
buffers. This requires amending the defer code to maintaine ordered
buffer state across defer rolls for the sake of the dquot allocation
code.

For regular operations we preserve the current behavior since the dquot
items require properly initialized ondisk dquot records.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

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xfs: use a xfs_btree_cur for the ->finish_cleanup state

Given how XFS is all based around btrees it doesn't make much sense
to offer a totally generic state when we can just use the btree cursor.

S

xfs: use a xfs_btree_cur for the ->finish_cleanup state

Given how XFS is all based around btrees it doesn't make much sense
to offer a totally generic state when we can just use the btree cursor.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: turn dfp_done into a xfs_log_item

All defer op instance place their own extension of the log item into
the dfp_done field. Replace that with a xfs_log_item to improve type
safety and make the

xfs: turn dfp_done into a xfs_log_item

All defer op instance place their own extension of the log item into
the dfp_done field. Replace that with a xfs_log_item to improve type
safety and make the code easier to follow.

Also use the opportunity to improve the ->finish_item calling conventions
to place the done log item as the higher level structure before the
list_entry used for the individual items.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: refactor xfs_defer_finish_noroll

Split out a helper that operates on a single xfs_defer_pending structure
to untangle the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian

xfs: refactor xfs_defer_finish_noroll

Split out a helper that operates on a single xfs_defer_pending structure
to untangle the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: merge the ->diff_items defer op into ->create_intent

This avoids a per-item indirect call, and also simplifies the interface
a bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: B

xfs: merge the ->diff_items defer op into ->create_intent

This avoids a per-item indirect call, and also simplifies the interface
a bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: merge the ->log_item defer op into ->create_intent

These are aways called together, and my merging them we reduce the amount
of indirect calls, improve type safety and in general clean up the c

xfs: merge the ->log_item defer op into ->create_intent

These are aways called together, and my merging them we reduce the amount
of indirect calls, improve type safety and in general clean up the code
a bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: factor out a xfs_defer_create_intent helper

Create a helper that encapsulates the whole logic to create a defer
intent. This reorders some of the work that was done, but none of
that has an af

xfs: factor out a xfs_defer_create_intent helper

Create a helper that encapsulates the whole logic to create a defer
intent. This reorders some of the work that was done, but none of
that has an affect on the operation as only fields that don't directly
interact are affected.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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fs: xfs: Remove KM_NOSLEEP and KM_SLEEP.

Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP,
we can remove KM_NOSLEEP and replace KM_SLEEP with 0.

Signed-off-by: Tetsuo Handa <p

fs: xfs: Remove KM_NOSLEEP and KM_SLEEP.

Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP,
we can remove KM_NOSLEEP and replace KM_SLEEP with 0.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: remove unused header files

There are many, many xfs header files which are included but
unneeded (or included twice) in the xfs code, so remove them.

nb: xfs_linux.h includes about 9 headers f

xfs: remove unused header files

There are many, many xfs header files which are included but
unneeded (or included twice) in the xfs code, so remove them.

nb: xfs_linux.h includes about 9 headers for everyone, so those
explicit includes get removed by this. I'm not sure what the
preference is, but if we wanted explicit includes everywhere,
a followup patch could remove those xfs_*.h includes from
xfs_linux.h and move them into the files that need them.
Or it could be left as-is.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: always rejoin held resources during defer roll

During testing of xfs/141 on a V4 filesystem, I observed some
inconsistent behavior with regards to resources that are held (i.e.
remain locked) a

xfs: always rejoin held resources during defer roll

During testing of xfs/141 on a V4 filesystem, I observed some
inconsistent behavior with regards to resources that are held (i.e.
remain locked) across a defer roll. The transaction roll always gives
the defer roll function a new transaction, even if committing the old
transaction fails. However, the defer roll function only rejoins the
held resources if the transaction commit succeedied. This means that
callers of defer roll have to figure out whether the held resources are
attached to the transaction being passed back.

Worse yet, if the defer roll was part of a defer finish call, we have a
third possibility: the defer finish could pass back a dirty transaction
with dirty held resources and an error code.

The only sane way to handle all of these scenarios is to require that
the code that held the resource either cancel the transaction before
unlocking and releasing the resources, or use functions that detach
resources from a transaction properly (e.g. xfs_trans_brelse) if they
need to drop the reference before committing or cancelling the
transaction.

In order to make this so, change the defer roll code to join held
resources to the new transaction unconditionally and fix all the bhold
callers to release the held buffers correctly.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

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xfs: streamline defer op type handling

There's no need to bundle a pointer to the defer op type into the defer
op control structure. Instead, store the defer op type enum, which
enables us to short

xfs: streamline defer op type handling

There's no need to bundle a pointer to the defer op type into the defer
op control structure. Instead, store the defer op type enum, which
enables us to shorten some of the lines.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

show more ...

xfs: idiotproof defer op type configuration

Recently, we forgot to port a new defer op type to xfsprogs, which
caused us some userspace pain. Reorganize the way we make libxfs
clients supply defer

xfs: idiotproof defer op type configuration

Recently, we forgot to port a new defer op type to xfsprogs, which
caused us some userspace pain. Reorganize the way we make libxfs
clients supply defer op type information so that all type information
has to be provided at build time instead of risky runtime dynamic
configuration.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

show more ...

xfs: fold dfops into the transaction

struct xfs_defer_ops has now been reduced to a single list_head. The
external dfops mechanism is unused and thus everywhere a (permanent)
transaction is accessib

xfs: fold dfops into the transaction

struct xfs_defer_ops has now been reduced to a single list_head. The
external dfops mechanism is unused and thus everywhere a (permanent)
transaction is accessible the associated dfops structure is as well.

Remove the xfs_defer_ops structure and fold the list_head into the
transaction. Also remove the last remnant of external dfops in
xfs_trans_dup().

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: pass transaction to xfs_defer_add()

The majority of remaining references to struct xfs_defer_ops in XFS
are associated with xfs_defer_add(). At this point, there are no
more external xfs_defer_

xfs: pass transaction to xfs_defer_add()

The majority of remaining references to struct xfs_defer_ops in XFS
are associated with xfs_defer_add(). At this point, there are no
more external xfs_defer_ops users left. All instances of
xfs_defer_ops are embedded in the transaction, which means we can
safely pass the transaction down to the dfops add interface.

Update xfs_defer_add() to receive the transaction as a parameter.
Various subsystems implement wrappers to allocate and construct the
context specific data structures for the associated deferred
operation type. Update these to also carry the transaction down as
needed and clean up unused dfops parameters along the way.

This removes most of the remaining references to struct
xfs_defer_ops throughout the code and facilitates removal of the
structure.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[darrick: fix unused variable warnings with ftrace disabled]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: replace xfs_defer_ops ->dop_pending with on-stack list

The xfs_defer_ops ->dop_pending list is used to track active
deferred operations once intents are logged. These items must be
aborted in t

xfs: replace xfs_defer_ops ->dop_pending with on-stack list

The xfs_defer_ops ->dop_pending list is used to track active
deferred operations once intents are logged. These items must be
aborted in the event of an error. The list is populated as intents
are logged and items are removed as they complete (or are aborted).

Now that xfs_defer_finish() cancels on error, there is no need to
ever access ->dop_pending outside of xfs_defer_finish(). The list is
only ever populated after xfs_defer_finish() begins and is either
completed or cancelled before it returns.

Remove ->dop_pending from xfs_defer_ops and replace it with a local
list in the xfs_defer_finish() path. Pass the local list to the
various helpers now that it is not accessible via dfops. Note that
we have to check for NULL in the abort case as the final tx roll
occurs outside of the scope of the new local list (once the dfops
has completed and thus drained the list).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: cancel dfops on xfs_defer_finish() error

The current semantics of xfs_defer_finish() require the caller to
call xfs_defer_cancel() on error. This is slightly inconsistent with
transaction commi

xfs: cancel dfops on xfs_defer_finish() error

The current semantics of xfs_defer_finish() require the caller to
call xfs_defer_cancel() on error. This is slightly inconsistent with
transaction commit error handling where a failed commit cleans up
the transaction before returning.

More significantly, the only requirement for exposure of
->dop_pending outside of xfs_defer_finish() is so that
xfs_defer_cancel() can drain it on error. Since the only recourse of
xfs_defer_finish() errors is cancellation, mirror the transaction
logic and cancel remaining dfops before returning from
xfs_defer_finish() with an error.

Beside simplifying xfs_defer_finish() semantics, this ensures that
xfs_defer_finish() always returns with an empty ->dop_pending and
thus facilitates removal of the list from xfs_defer_ops.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: clean out superfluous dfops dop params/vars

The dfops code still passes around the xfs_defer_ops pointer
superfluously in a few places. Clean this up wherever the
transaction will suffice.

Sig

xfs: clean out superfluous dfops dop params/vars

The dfops code still passes around the xfs_defer_ops pointer
superfluously in a few places. Clean this up wherever the
transaction will suffice.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: drop dop param from xfs_defer_op_type ->finish_item() callback

The dfops infrastructure ->finish_item() callback passes the
transaction and dfops as separate parameters. Since dfops is always
p

xfs: drop dop param from xfs_defer_op_type ->finish_item() callback

The dfops infrastructure ->finish_item() callback passes the
transaction and dfops as separate parameters. Since dfops is always
part of a transaction, the latter parameter is no longer necessary.
Remove it from the various callbacks.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: automatic dfops inode relogging

Inodes that are held across deferred operations are explicitly
joined to the dfops structure to ensure appropriate relogging.
While inodes are currently joined e

xfs: automatic dfops inode relogging

Inodes that are held across deferred operations are explicitly
joined to the dfops structure to ensure appropriate relogging.
While inodes are currently joined explicitly, we can detect the
conditions that require relogging at dfops finish time by inspecting
the transaction item list for inodes with ili_lock_flags == 0.

Replace the xfs_defer_ijoin() infrastructure with such detection and
automatic relogging of held inodes. This eliminates the need for the
per-dfops inode list, replaced by an on-stack variant in
xfs_defer_trans_roll().

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: automatic dfops buffer relogging

Buffers that are held across deferred operations are explicitly
joined to the dfops structure to ensure appropriate relogging.
While buffers are currently joine

xfs: automatic dfops buffer relogging

Buffers that are held across deferred operations are explicitly
joined to the dfops structure to ensure appropriate relogging.
While buffers are currently joined explicitly, we can detect the
conditions that require relogging at dfops finish time by inspecting
the transaction item list for held buffers.

Replace the xfs_defer_bjoin() infrastructure with such detection and
automatic relogging of held buffers. This eliminates the need for
the per-dfops buffer list, replaced by an on-stack variant in
xfs_defer_trans_roll().

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: replace dop_low with transaction flag

The dop_low field enables the low free space allocation mode when a
previous allocation has detected difficulty allocating blocks. It
has historically been

xfs: replace dop_low with transaction flag

The dop_low field enables the low free space allocation mode when a
previous allocation has detected difficulty allocating blocks. It
has historically been part of the xfs_defer_ops structure, which
means if enabled, it remains enabled across a set of transactions
until the deferred operations have completed and the dfops is reset.

Now that the dfops is embedded in the transaction, we can save a bit
more space by using a transaction flag rather than a standalone
boolean. Drop the ->dop_low field and replace it with a transaction
flag that is set at the same points, carried across rolling
transactions and cleared on completion of deferred operations. This
essentially emulates the behavior of ->dop_low and so should not
change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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xfs: pass transaction to dfops reset/move helpers

All callers pass ->t_dfops of the associated transactions. Refactor
the helpers to receive the transactions and facilitate further
cleanups between

xfs: pass transaction to dfops reset/move helpers

All callers pass ->t_dfops of the associated transactions. Refactor
the helpers to receive the transactions and facilitate further
cleanups between xfs_defer_ops and xfs_trans.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: remove unused __xfs_defer_cancel() internal helper

With no more external dfops users, there is no need for an
xfs_defer_ops cancel wrapper.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Rev

xfs: remove unused __xfs_defer_cancel() internal helper

With no more external dfops users, there is no need for an
xfs_defer_ops cancel wrapper.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

show more ...

xfs: bypass final dfops roll in trans commit path

Once xfs_defer_finish() has completed all deferred operations, it
checks the dirty state of the transaction and rolls it once more to
return a clean

xfs: bypass final dfops roll in trans commit path

Once xfs_defer_finish() has completed all deferred operations, it
checks the dirty state of the transaction and rolls it once more to
return a clean transaction for the caller. This primarily to cover
the case where repeated xfs_defer_finish() calls are made in a loop
and we need to make sure that the caller starts the next iteration
with a clean transaction. Otherwise we risk transaction reservation
overrun.

This final transaction roll is not required in the transaction
commit path, however, because the transaction is immediately
committed and freed after dfops completion. Refactor the final roll
into a separate helper such that we can avoid it in the transaction
commit path. Lift the dfops reset as well so dfops remains valid
until after the last call to xfs_defer_trans_roll(). The reset is
also unnecessary in the transaction commit path because the
transaction is about to complete.

This eliminates unnecessary regrants of transactions where the
associated transaction roll can be replaced by a transaction commit.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

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