Brian Foster [Tue, 24 Jul 2018 20:43:08 +0000 (13:43 -0700)]
xfs: use ->t_dfops in log recovery intent processing
xlog_finish_defer_ops() processes the deferred operations collected
over the entire intent recovery sequence. We can't xfs_defer_init()
here because the dfops is already populated. Attach it manually and
eliminate the last caller of xfs_defer_finish() that doesn't pass
->t_dfops.
Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Brian Foster [Tue, 24 Jul 2018 20:43:07 +0000 (13:43 -0700)]
xfs: pull up dfops from xfs_itruncate_extents()
xfs_itruncate_extents[_flags]() uses a local dfops with a
transaction provided by the caller. It uses hacky ->t_dfops
replacement logic to avoid stomping over an already populated
->t_dfops.
The latter never occurs for current callers and the logic itself is
not really appropriate. Clean this up by updating all callers to
initialize a dfops and to use that down in xfs_itruncate_extents().
This more closely resembles the upcoming logic where dfops will be
embedded within the transaction. We can also replace the
xfs_defer_init() in the xfs_itruncate_extents_flags() loop with an
assert. Both dfops and firstblock should be in a valid state
after xfs_defer_finish() and the inode joined to the dfops is fixed
throughout the loop.
Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Darrick J. Wong [Fri, 20 Jul 2018 16:28:40 +0000 (09:28 -0700)]
xfs: force summary counter recalc at next mount
Use the "bad summary count" mount flag from the previous patch to skip
writing the unmount record to force log recovery at the next mount,
which will recalculate the summary counters for us.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
Darrick J. Wong [Thu, 19 Jul 2018 19:29:13 +0000 (12:29 -0700)]
xfs: detect and fix bad summary counts at mount
Filippo Giunchedi complained that xfs doesn't even perform basic sanity
checks of the fs summary counters at mount time. Therefore, recalculate
the summary counters from the AGFs after log recovery if the counts were
bad (or we had to recover the fs). Enhance the recalculation routine to
fail the mount entirely if the new values are also obviously incorrect.
We use a mount state flag to record the "bad summary count" state so
that the (subsequent) online fsck patches can detect subtlely incorrect
counts and set the flag; clear it userspace asks for a repair; or force
a recalculation at the next mount if nobody fixes it by unmount time.
Reported-by: Filippo Giunchedi <fgiunchedi@wikimedia.org> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
Darrick J. Wong [Thu, 19 Jul 2018 19:29:11 +0000 (12:29 -0700)]
xfs: shorten xfs_scrub_ prefix
Shorten all the metadata checking xfs_scrub_ prefixes to xchk_. After
this, the only xfs_scrub* symbols are the ones that pertain to both
scrub and repair. Whitespace damage will be fixed in a subsequent
patch. There are no functional changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
Darrick J. Wong [Thu, 19 Jul 2018 19:29:10 +0000 (12:29 -0700)]
xfs: clean up xfs_btree_del_cursor callers
Less trivial cleanups of the error argument to xfs_btree_del_cursor;
these require some minor code refactoring.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
Darrick J. Wong [Thu, 19 Jul 2018 19:26:31 +0000 (12:26 -0700)]
xfs: trivial xfs_btree_del_cursor cleanups
The error argument to xfs_btree_del_cursor already understands the
"nonzero for error" semantics, so remove pointless error testing in the
callers and pass it directly.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
The root cause of the assertion failure is that xfs_defer_finish doesn't
roll the transaction after processing all the deferred items. Therefore
it returns a dirty transaction to the caller, which leaves the caller at
risk of exceeding the transaction reservation if it logs more items.
Brian Foster's patchset to move the defer_ops firstblock into the
transaction requires t_firstblock == NULLFSBLOCK upon defer_ops
initialization, which is how this was noticed at all.
Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
Darrick J. Wong [Thu, 19 Jul 2018 19:24:55 +0000 (12:24 -0700)]
xfs: check leaf attribute block freemap in verifier
Check the leaf attribute freemap when we're verifying the block.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
Carlos Maiolino [Tue, 17 Jul 2018 21:25:20 +0000 (14:25 -0700)]
libxfs: Fix a couple of sparse complaintis
No significant changes, just silence a couple of sparse errors.
Using cpu_to_be32(NULLAGINO), the NULLAGINO constant will be encoded in
BE as a constant, avoiding a BE -> CPU conversion every iteraction of
the loop, if be32_to_cpu(agi->agi_unlinked[i]) was used instead.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Make use of the swap macro and remove unnecessary variable *tmp*. This
makes the code easier to read and maintain. Also, slightly refactor some
code.
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Make use of the swap macro and remove some unnecessary variables.
This makes the code easier to read and maintain. Also, reduces the
stack usage.
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
xfs_attr_leaf: use swap macro in xfs_attr3_leaf_rebalance
Make use of the swap macro and remove some unnecessary variables.
This makes the code easier to read and maintain. Also, reduces the
stack usage.
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Darrick J. Wong [Tue, 17 Jul 2018 21:24:11 +0000 (14:24 -0700)]
xfs: don't assume a left rmap when allocating a new rmap
The original rmap code assumed that there would always be at least one
rmap in the rmapbt (the AG sb/agf/agi) and so errored out if it didn't
find one. This assumption isn't true for the rmapbt repair function
(and it won't be true for realtime rmap either), so remove the check and
just deal with the situation.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Eric Sandeen [Thu, 12 Jul 2018 05:26:36 +0000 (22:26 -0700)]
xfs: remove unused iolock arg from xfs_break_dax_layouts
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Brian Foster [Thu, 12 Jul 2018 05:26:35 +0000 (22:26 -0700)]
xfs: kill __xfs_buf_submit_common()
Now that there is only one caller, fold the common submission helper
into __xfs_buf_submit().
Suggested-by: Christoph Hellwig <hch@infradead.org> 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>
Brian Foster [Thu, 12 Jul 2018 05:26:35 +0000 (22:26 -0700)]
xfs: combine [a]sync buffer submission apis
The buffer I/O submission path consists of separate function calls
per type. The buffer I/O type is already controlled via buffer
state (XBF_ASYNC), however, so there is no real need for separate
submission functions.
Combine the buffer submission functions into a single function that
processes the buffer appropriately based on XBF_ASYNC. Retain an
internal helper with a conditional wait parameter to continue to
support batched !XBF_ASYNC submission/completion required by delwri
queues.
Suggested-by: Christoph Hellwig <hch@infradead.org> 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>
Brian Foster [Thu, 12 Jul 2018 05:26:34 +0000 (22:26 -0700)]
xfs: use sync buffer I/O for sync delwri queue submission
If a delwri queue occurs of a buffer that sits on a delwri queue
wait list, the queue sets _XBF_DELWRI_Q without changing the state
of ->b_list. This occurs, for example, if another thread beats the
current delwri waiter thread to the buffer lock after I/O
completion. Once the waiter acquires the lock, it removes the buffer
from the wait list and leaves a buffer with _XBF_DELWRI_Q set but
not populated on a list. This results in a lost buffer submission
and in turn can result in assert failures due to _XBF_DELWRI_Q being
set on buffer reclaim or filesystem lockups if the buffer happens to
cover an item in the AIL.
This problem has been reproduced by repeated iterations of xfs/305
on high CPU count (28xcpu) systems with limited memory (~1GB). Dirty
dquot reclaim races with an xfsaild push of a separate dquot backed
by the same buffer such that the buffer sits on the reclaim wait
list at the time xfsaild attempts to queue it. Since the latter
dquot has been flush locked but the underlying buffer not submitted
for I/O, the dquot pins the AIL and causes the filesystem to
livelock.
This race is essentially made possible by the buffer lock cycle
involved with waiting on a synchronous delwri queue submission.
Close the race by using synchronous buffer I/O for respective delwri
queue submission. This means the buffer remains locked across the
I/O and so is inaccessible from other contexts while in the
intermediate wait list state. The sync buffer I/O wait mechanism is
factored into a helper such that sync delwri buffer submission and
serialization are batched operations.
Designed-by: Dave Chinner <dchinner@redhat.com> Signed-off-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>
Brian Foster [Thu, 12 Jul 2018 05:26:34 +0000 (22:26 -0700)]
xfs: refactor buffer submission into a common helper
Sync and async buffer submission both do generally similar things
with a couple odd exceptions. Refactor the core buffer submission
code into a common helper to isolate buffer submission from
completion handling of synchronous buffer I/O.
This patch does not change behavior. It is a step towards support
for using synchronous buffer I/O via synchronous delwri queue
submission.
Designed-by: Dave Chinner <dchinner@redhat.com> 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>
Brian Foster [Thu, 12 Jul 2018 05:26:33 +0000 (22:26 -0700)]
xfs: remove xfs_defer_init() firstblock param
All but one caller of xfs_defer_init() passes in the ->t_firstblock
of the associated transaction. The one outlier is
xlog_recover_process_intents(), which simply passes a dummy value
because a valid pointer is required. This firstblock variable can
simply be removed.
At this point we could remove the xfs_defer_init() firstblock
parameter and initialize ->t_firstblock directly. Even that is not
necessary, however, because ->t_firstblock is automatically
reinitialized in the new transaction on a transaction roll. Since
xfs_defer_init() should never occur more than once on a particular
transaction (since the corresponding finish will roll it), replace
the reinit from xfs_defer_init() with an assert that verifies the
transaction has a NULLFSBLOCK firstblock.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:32 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in inode inactivate
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>
Brian Foster [Thu, 12 Jul 2018 05:26:32 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in extent swap
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>
Brian Foster [Thu, 12 Jul 2018 05:26:31 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in reflink cow block cancel
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>
Brian Foster [Thu, 12 Jul 2018 05:26:31 +0000 (22:26 -0700)]
xfs: replace no-op firstblock init with ->t_firstblock
xfs_refcount_recover_cow_leftovers() has no need for a firstblock
variable and so passes an unrelated xfs_fsblock_t to
xfs_defer_init() to avoid declaring one. Replace this no-op
initialization with ->t_firstblock. This will be optimized away by
the removal of the xfs_defer_init() firstblock param.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:30 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in dq alloc
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>
Brian Foster [Thu, 12 Jul 2018 05:26:30 +0000 (22:26 -0700)]
xfs: remove xfs_alloc_arg firstblock field
The xfs_alloc_arg.firstblock field is used to control the starting
agno for an allocation. The structure already carries a pointer to
the transaction, which carries the current firstblock value.
Remove the field and access ->t_firstblock directly in the
allocation code.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:29 +0000 (22:26 -0700)]
xfs: remove xfs_btree_cur private firstblock field
The bmbt cursor private structure has a firstblock field that is
used to maintain locking order on bmbt allocations. The field holds
an actual firstblock value (as opposed to a pointer), so it is
initialized on cursor creation, updated on allocation and then the
value is transferred back to the source before the cursor is
destroyed.
This value is always transferred from and back to the ->t_firstblock
field. Since xfs_btree_cur already carries a reference to the
transaction, we can remove this field from xfs_btree_cur and the
associated copying. The bmbt allocations will update the value in
the transaction directly.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:29 +0000 (22:26 -0700)]
xfs: remove bmap format helpers firstblock params
The bmap format helpers receive firstblock via ->t_firstblock. Drop
the param and access it directly.
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>
The add extent helpers all receive firstblock via ->t_firstblock.
Drop the parameter and access it directly.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:28 +0000 (22:26 -0700)]
xfs: remove xfs_bmalloca firstblock field
The xfs_bmalloca.firstblock field carries the firstblock value from
the transaction into the bmap infrastructure. It's initialized in
one place from ->t_firstblock, so drop the field and access
->t_firstblock directly throughout the bmap code.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:27 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in bmap extent split
Also remove the unnecessary xfs_bmap_split_extent_at() parameter.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:27 +0000 (22:26 -0700)]
xfs: remove bmap insert/collapse firstblock param
The only callers pass ->t_firstblock.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:25 +0000 (22:26 -0700)]
xfs: remove xfs_bunmapi() firstblock param
All callers pass ->t_firstblock from the current transaction.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:25 +0000 (22:26 -0700)]
xfs: remove xfs_bmapi_write() firstblock param
All callers pass ->t_firstblock from the current transaction.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:24 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in insert/collapse range
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>
Brian Foster [Thu, 12 Jul 2018 05:26:24 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in xfs_bmapi_remap()
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>
Brian Foster [Thu, 12 Jul 2018 05:26:23 +0000 (22:26 -0700)]
xfs: use ->t_firstblock for all xfs_bunmapi() callers
Convert all xfs_bunmapi() callers to ->t_firstblock.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:23 +0000 (22:26 -0700)]
xfs: use ->t_firstblock for all xfs_bmapi_write() callers
Convert all xfs_bmapi_write() users to ->t_firstblock.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:22 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in xattr ops
Similar to the dirops code, the xattr code uses an on-stack
firstblock variable for the various operations. This code rolls the
underlying transaction in various places, however, which means we
cannot simply replace the local firstblock vars with ->t_firstblock.
Doing so (without further changes) would invalidate the memory
pointed to by xfs_da_args.firstblock as soon as the first
transaction rolls.
To avoid this problem, remove xfs_da_args.firstblock and replace all
such accesses with ->t_firstblock at the same time. This ensures
that accesses to the current firstblock always occur through the
current transaction rather than a potentially invalid xfs_da_args
pointer.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:21 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in attrfork add
Note that this codepath is a user of struct xfs_da_args. Switch it
over to ->t_firstblock in preparation to remove
xfs_da_args.firstblock.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:21 +0000 (22:26 -0700)]
xfs: remove firstblock param from xfs dir ops
All callers of the xfs_dir_*() functions pass ->t_firstblock as the
firstblock parameter. Drop the parameter and access ->t_firstblock
directly.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:20 +0000 (22:26 -0700)]
xfs: use ->t_firstblock in dir ops
Callers of the xfs_dir_*() functions currently pass an on-stack
firstblock variable. While the dirops infrastructure carries a
pointer to this variable, it never rolls the transaction and so it
is safe to use ->t_firstblock instead.
Fix up the various xfs_dir_*() callers to use ->t_firstblock. Also
remove the unnecessary parameter for xfs_cross_rename().
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>
Brian Foster [Thu, 12 Jul 2018 05:26:20 +0000 (22:26 -0700)]
xfs: add firstblock field to xfs_trans
A firstblock var is typically allocated and initialized along with
xfs_defer_ops structures and passed around independent from the
associated transaction. To facilitate combining the two, add an
optional ->t_firstblock field to xfs_trans that can be used in place
of an on-stack variable.
The firstblock value follows the lifetime of the transaction, so
initialize it on allocation and when a transaction rolls.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:19 +0000 (22:26 -0700)]
xfs: allow null firstblock in xfs_bmapi_write() when tp is null
xfs_bmapi_write() always expects a valid firstblock pointer. It
immediately dereferences the pointer to help determine how to
initialize the bma.minleft field. The remaining accesses are
related to modifying btree format forks, which is only relevant for
!COW fork callers.
The reflink code passes a NULL transaction to xfs_bmapi_write() in a
couple places that do COW fork unwritten conversion. The purpose of
the firstblock field is to track the first block allocation in the
current transaction, so technically firstblock should not be
required for these callers either.
Tweak xfs_bmapi_write() to initialize the bma correctly without
accessing the firstblock pointer if no transaction is provided in
the first place. Update the reflink callers to pass NULL instead of
otherwise unused firstblock references.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:19 +0000 (22:26 -0700)]
xfs: refactor dfops init to attach to transaction
Most callers of xfs_defer_init() immediately attach the dfops
structure to a transaction. Add a transaction parameter to eliminate
much of this boilerplate code. This also helps self-document the
fact that many codepaths now expect a dfops pointer implicitly via
xfs_trans->t_dfops.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:18 +0000 (22:26 -0700)]
xfs: use ->t_dfops in reflink cow recover path
Use ->t_dfops of the leftover COW reservation cleanup transaction.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:18 +0000 (22:26 -0700)]
xfs: use ->t_dfops in cancel cow blocks operation
Use ->t_dfops of the transaction from the caller. Reset it before we
return to avoid leaks of local stack memory.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:17 +0000 (22:26 -0700)]
xfs: use ->t_dfops for rmap extent swap operations
xfs_swap_extent_rmap() uses a local dfops instance with a
transaction from the caller. Since there is only one caller, pull
the dfops structure into the caller and attach it to the
transaction. This avoids the need to clear ->t_dfops to prevent
invalid stack memory access.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:17 +0000 (22:26 -0700)]
xfs: remove unused btree cursor bc_private.a.dfops field
The xfs_btree_cur.bc_private.a.dfops field is only ever initialized
by the refcountbt cursor init function. The only caller of that
function with a non-NULL dfops is from deferred completion context,
which already has attached to ->t_dfops.
In addition to that, the only actual reference of a.dfops is the
cursor duplication function, which means the field is effectively
unused.
Remove the dfops field from the bc_private.a union. Any future users
can acquire the dfops from the transaction. This patch does not
change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:16 +0000 (22:26 -0700)]
xfs: remove xfs_btree_cur bmbt dfops field
All assignments of xfs_btree_cur.bc_private.b.dfops originate from
->t_dfops. Replace accesses of the former with the latter and remove
the unnecessary field. This patch does not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:16 +0000 (22:26 -0700)]
xfs: remove dfops param from internal bmap extent helpers
All callers of the various bmap extent helpers now use ->t_dfops.
Remove the unnecessary dfops params and access ->t_dfops directly.
This patch does not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:15 +0000 (22:26 -0700)]
xfs: use ->t_dfops for collapse/insert range operations
Use ->t_dfops for the collapse and insert range transactions. These
are the only callers of the respective bmap helpers, so replace the
unnecessary dfops parameters with direct accesses to ->t_dfops.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:14 +0000 (22:26 -0700)]
xfs: remove struct xfs_bmalloca dfops field
Now that bma.dfops is only assigned from ->t_dfops, replace all
accesses to the former with the latter and remove the unnecessary
field. This patch does not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:14 +0000 (22:26 -0700)]
xfs: remove xfs_bmapi_remap() dfops param
All xfs_bmapi_remap() callers already use ->t_dfops. Note that
deferred completion context unconditionally sets ->t_dfops if it
hasn't already been set by the caller. Remove the unnecessary
parameter and access ->t_dfops directly.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:13 +0000 (22:26 -0700)]
xfs: remove xfs_bunmapi() dfops param
Now that all xfs_bunmapi() callers use ->t_dfops, remove the
unnecessary parameter and access ->t_dfops directly. This patch does
not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:13 +0000 (22:26 -0700)]
xfs: use ->t_dfops for all xfs_bunmapi() callers
Use ->t_dfops for all remaining xfs_bunmapi() callers. This prepares
the latter to no longer require a dfops parameter.
Note that xfs_itruncate_extents_flags() associates a local dfops
with a transaction provided from the caller. Since there are
multiple callers, set and reset ->t_dfops before the function
returns to avoid exposure of stack memory to the caller.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:12 +0000 (22:26 -0700)]
xfs: remove xfs_bmapi_write() dfops param
Now that all callers use ->t_dfops, the xfs_bmapi_write() dfops
parameter is no longer necessary. Remove it and access ->t_dfops
directly. This patch does not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:12 +0000 (22:26 -0700)]
xfs: use ->t_dfops for all xfs_bmapi_write() callers
Attach ->t_dfops for all remaining callers of xfs_bmapi_write().
This prepares the latter to no longer require a separate dfops
parameter.
Note that xfs_symlink() already uses ->t_dfops. Fix up the local
references for consistency.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:11 +0000 (22:26 -0700)]
xfs: use ->t_dfops in dqalloc transaction
xfs_dquot_disk_alloc() receives a transaction from the caller and
passes a local dfops along to xfs_bmapi_write(). If we attach this
dfops to the transaction, we have to make sure to clear it before
returning to avoid invalid access of stack memory.
Since xfs_qm_dqread_alloc() is the only caller, pull dfops into the
caller and attach it to the transaction to eliminate this pattern
entirely.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:11 +0000 (22:26 -0700)]
xfs: replace xfs_da_args->dfops accesses with ->t_dfops and remove
Now that xfs_da_args->dfops is always assigned from a ->t_dfops
pointer (or one that is immediately attached), replace all
downstream accesses of the former with the latter and remove the
field from struct xfs_da_args.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:10 +0000 (22:26 -0700)]
xfs: use ->t_dfops in extent split tx and remove param
Attach the local dfops to ->t_dfops of the extent split transaction.
Since this is the only caller of xfs_bmap_split_extent_at(), remove
the dfops parameter as well.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:10 +0000 (22:26 -0700)]
xfs: remove dfops param in attr fork add path
Now that the attribute fork add tx carries dfops along with the
transaction, it is unnecessary to pass it down the stack. Remove the
dfops parameter and access ->t_dfops directly where necessary. This
patch does not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:09 +0000 (22:26 -0700)]
xfs: use ->t_dfops for attr set/remove operations
Attach the local dfops to the transaction allocated for xattr add
and remove operations. Add an earlier initialization in
xfs_attr_remove() to ensure the structure is valid if it remains
unused at transaction commit time.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:09 +0000 (22:26 -0700)]
xfs: use ->t_dfops for recovery of [b|c]ui log items
Log recovery passes down a central dfops structure to recovery
handlers for bui and cui log items. Each of these handlers allocates
and commits a transaction and defers any remaining operations to be
completed by the main recovery sequence.
Since dfops outlives the transaction in this context, set and clear
->t_dfops appropriately such that the *_finish_item() paths and
below (i.e., xfs_bmapi*()) can expect to find the dfops in the
transaction without it being committed with the dfops attached. This
is required because transaction commit expects that an associated
dfops is finished and in this context the dfops may be populated at
commit time.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:08 +0000 (22:26 -0700)]
xfs: remove dfops param from high level dirname calls
All callers of the directory create, rename and remove interfaces
already associate the dfops with the transaction. Drop the dfops
parameters in these calls in preparation for further cleanups in the
layers below. This patch does not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:07 +0000 (22:26 -0700)]
xfs: remove dfops parameter from ifree call stack
The inode free callchain starting in xfs_inactive_ifree() already
associates its dfops with the transaction. It still passes the dfops
on the stack down through xfs_difree_inobt(), however.
Clean up the call stack and reference dfops directly from the
transaction. This patch does not change behavior.
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>
Brian Foster [Thu, 12 Jul 2018 05:26:07 +0000 (22:26 -0700)]
xfs: rename xfs_trans ->t_agfl_dfops to ->t_dfops
The ->t_agfl_dfops field is currently used to defer agfl block frees
from associated transaction contexts. While all known problematic
contexts have already been updated to use ->t_agfl_dfops, the
broader goal is defer agfl frees from all callers that already use a
deferred operations structure. Further, the transaction field
facilitates a good amount of code clean up where the transaction and
dfops have historically been passed down through the stack
separately.
Rename the field to something more generic to prepare to use it as
such throughout XFS. This patch does not change behavior. 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>
A couple COW fork unwritten extent conversion helpers pass an
uninitialized dfops pointer to xfs_bmapi_write(). This does not
cause problems because conversion does not use a transaction or the
dfops structure for the COW fork. Drop the uninitialized usage of
dfops in these codepaths and pass NULL along to xfs_bmapi_write()
instead.
Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@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>
xfs: update my copyrights for the writeback and iomap 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>
xfs: add support for sub-pagesize writeback without buffer_heads
Switch to using the iomap_page structure for checking sub-page uptodate
status and track sub-page I/O completion status, and remove large
quantities of boilerplate code working around buffer heads.
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>
iomap: add support for sub-pagesize buffered I/O without buffer heads
After already supporting a simple implementation of buffered writes for
the blocksize == PAGE_SIZE case in the last commit this adds full support
even for smaller block sizes. There are three bits of per-block
information in the buffer_head structure that really matter for the iomap
read and write path:
- uptodate status (BH_uptodate)
- marked as currently under read I/O (BH_Async_Read)
- marked as currently under write I/O (BH_Async_Write)
Instead of having new per-block structures this now adds a per-page
structure called struct iomap_page to track this information in a slightly
different form:
- a bitmap for the per-block uptodate status. For worst case of a 64k
page size system this bitmap needs to contain 128 bits. For the
typical 4k page size case it only needs 8 bits, although we still
need a full unsigned long due to the way the atomic bitmap API works.
- two atomic_t counters are used to track the outstanding read and write
counts
There is quite a bit of boilerplate code as the buffered I/O path uses
various helper methods, but the actual code is very straight forward.
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>
xfs: allow writeback on pages without buffer heads
Disable the IOMAP_F_BUFFER_HEAD flag on file systems with a block size
equal to the page size, and deal with pages without buffer heads in
writeback. Thanks to the previous refactoring this is basically trivial
now.
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>
Rejuggle how we deal with the different error vs non-error and have
ioends vs not have ioend cases to keep the fast path streamlined, and
the duplicate code at a minimum.
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>
This helper only has two callers, one of them with a constant error
argument. Remove it to make pending changes to the code a little easier.
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>
xfs: move all writeback buffer_head manipulation into xfs_map_at_offset
This keeps it in a single place so it can be made otional more easily.
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>
xfs: don't look at buffer heads in xfs_add_to_ioend
Calculate all information for the bio based on the passed in information
without requiring a buffer_head structure.
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>
Simplify the way we check for a valid imap - we know we have a valid
mapping after xfs_map_blocks returned successfully, and we know we can
call xfs_imap_valid on any imap, as it will always fail on a
zero-initialized map.
We can also remove the xfs_imap_valid function and fold it into
xfs_map_blocks now.
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>
xfs: simplify xfs_map_blocks by using xfs_iext_lookup_extent directly
xfs_bmapi_read adds zero value in xfs_map_blocks. Replace it with a
direct call to the low-level extent lookup function.
Note that we now always pass a 0 length to the trace points as we ask
for an unspecified len.
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>
We only have one caller left, and open coding the simple extent list
lookup in it allows us to make the code both more understandable and
reuse calculations and variables already present.
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>
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>
Dave Chinner [Thu, 12 Jul 2018 05:26:00 +0000 (22:26 -0700)]
xfs: make xfs_writepage_map extent map centric
xfs_writepage_map() iterates over the bufferheads on a page to decide
what sort of IO to do and what actions to take. However, when it comes
to reflink and deciding when it needs to execute a COW operation, we no
longer look at the bufferhead state but instead we ignore than and look
up internal state held in the COW fork extent list.
This means xfs_writepage_map() is somewhat confused. It does stuff, then
ignores it, then tries to handle the impedence mismatch by shovelling the
results inside the existing mapping code. It works, but it's a bit of a
mess and it makes it hard to fix the cached map bug that the writepage
code currently has.
To unify the two different mechanisms, we first have to choose a direction.
That's already been set - we're de-emphasising bufferheads so they are no
longer a control structure as we need to do taht to allow for eventual
removal. Hence we need to move away from looking at bufferhead state to
determine what operations we need to perform.
We can't completely get rid of bufferheads yet - they do contain some
state that is absolutely necessary, such as whether that part of the page
contains valid data or not (buffer_uptodate()). Other state in the
bufferhead is redundant:
BH_dirty - the page is dirty, so we can ignore this and just
write it
BH_delay - we have delalloc extent info in the DATA fork extent
tree
BH_unwritten - same as BH_delay
BH_mapped - indicates we've already used it once for IO and it is
mapped to a disk address. Needs to be ignored for COW
blocks.
The BH_mapped flag is an interesting case - it's supposed to indicate that
it's already mapped to disk and so we can just use it "as is". In theory,
we don't even have to do an extent lookup to find where to write it too,
but we have to do that anyway to determine we are actually writing over a
valid extent. Hence it's not even serving the purpose of avoiding a an
extent lookup during writeback, and so we can pretty much ignore it.
Especially as we have to ignore it for COW operations...
Therefore, use the extent map as the source of information to tell us
what actions we need to take and what sort of IO we should perform. The
first step is to have xfs_map_blocks() set the io type according to what
it looks up. This means it can easily handle both normal overwrite and
COW cases. The only thing we also need to add is the ability to return
hole mappings.
We need to return and cache hole mappings now for the case of multiple
blocks per page. We no longer use the BH_mapped to indicate a block over
a hole, so we have to get that info from xfs_map_blocks(). We cache it so
that holes that span two pages don't need separate lookups. This allows us
to avoid ever doing write IO over a hole, too.
Now that we have xfs_map_blocks() returning both a cached map and the type
of IO we need to perform, we can rewrite xfs_writepage_map() to drop all
the bufferhead control. It's also much simplified because it doesn't need
to explicitly handle COW operations. Instead of iterating bufferheads, it
iterates blocks within the page and then looks up what per-block state is
required from the appropriate bufferhead. It then validates the cached
map, and if it's not valid, we get a new map. If we don't get a valid map
or it's over a hole, we skip the block.
At this point, we have to remap the bufferhead via xfs_map_at_offset().
As previously noted, we had to do this even if the buffer was already
mapped as the mapping would be stale for XFS_IO_DELALLOC, XFS_IO_UNWRITTEN
and XFS_IO_COW IO types. With xfs_map_blocks() now controlling the type,
even XFS_IO_OVERWRITE types need remapping, as converted-but-not-yet-
written delalloc extents beyond EOF can be reported at XFS_IO_OVERWRITE.
Bufferheads that span such regions still need their BH_Delay flags cleared
and their block numbers calculated, so we now unconditionally map each
bufferhead before submission.
But wait! There's more - remember the old "treat unwritten extents as
holes on read" hack? Yeah, that means we can have a dirty page with
unmapped, unwritten bufferheads that contain data! What makes these so
special is that the unwritten "hole" bufferheads do not have a valid block
device pointer, so if we attempt to write them xfs_add_to_ioend() blows
up. So we make xfs_map_at_offset() do the "realtime or data device"
lookup from the inode and ignore what was or wasn't put into the
bufferhead when the buffer was instantiated.
The astute reader will have realised by now that this code treats
unwritten extents in multiple-blocks-per-page situations differently.
If we get any combination of unwritten blocks on a dirty page that contain
valid data in the page, we're going to convert them to real extents. This
can actually be a win, because it means that pages with interleaving
unwritten and written blocks will get converted to a single written extent
with zeros replacing the interspersed unwritten blocks. This is actually
good for reducing extent list and conversion overhead, and it means we
issue a contiguous IO instead of lots of little ones. The downside is
that we use up a little extra IO bandwidth. Neither of these seem like a
bad thing given that spinning disks are seek sensitive, and SSDs/pmem have
bandwidth to burn and the lower Io latency/CPU overhead of fewer, larger
IOs will result in better performance on them...
As a result of all this, the only state we actually care about from the
bufferhead is a single flag - BH_Uptodate. We still use the bufferhead to
pass some information to the bio via xfs_add_to_ioend(), but that is
trivial to separate and pass explicitly. This means we really only need
1 bit of state per block per page from the buffered write path in the
writeback path. Everything else we do with the bufferhead is purely to
make the buffered IO front end continue to work correctly. i.e we've
pretty much marginalised bufferheads in the writeback path completely.
Signed-off-By: Dave Chinner <dchinner@redhat.com>
[hch: forward port, refactor and split off bits into other commits] 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>
xfs: rename the offset variable in xfs_writepage_map
Calling it file_offset makes the usage more clear, especially with
a new poffset variable that will be added soon for the offset inside
the page.
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>
We can handle the existing cow mapping case as a special case directly
in xfs_writepage_map, and share code for allocating delalloc blocks
with regular I/O in xfs_map_blocks. This means we need to always
call xfs_map_blocks for reflink inodes, but we can still skip most of
the work if it turns out that there is no COW mapping overlapping the
current block.
As a subtle detail we need to start caching holes in the wpc to deal
with the case of COW reservations between EOF. But we'll need that
infrastructure later anyway, so this is no big deal.
Based on a patch from Dave Chinner.
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>
We already have to check for overlapping COW extents everytime we
come back to a page in xfs_writepage_map / xfs_map_cow, so this
additional trim is not required.
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>
xfs: don't use XFS_BMAPI_IGSTATE in xfs_map_blocks
We want to be able to use the extent state as a reliably indicator for
the type of I/O, and stop using the buffer head state. For this we
need to stop using the XFS_BMAPI_IGSTATE so that we don't see merged
extents of different types.
Based on a patch from Dave Chinner.
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>
xfs: don't clear imap_valid for a non-uptodate buffers
Finding a buffer that isn't uptodate doesn't invalidate the mapping for
any given block. The last_sector check will already take care of starting
another ioend as soon as we find any non-update buffer, and if the current
mapping doesn't include the next uptodate buffer the xfs_imap_valid check
will take care of it.
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>
xfs: do not set the page uptodate in xfs_writepage_map
We already track the page uptodate status based on the buffer uptodate
status, which is updated whenever reading or zeroing blocks.
This code has been there since commit a ptool commit in 2002, which
claims to:
"merge" the 2.4 fsx fix for block size < page size to 2.5. This needed
major changes to actually fit.
and isn't present in other writepage implementations.
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>
xfs: move locking into xfs_bmap_punch_delalloc_range
Both callers want the same looking, so do it only once.
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>
Instead of looking at the buffer heads to see if a block is delalloc just
call xfs_bmap_punch_delalloc_range on the whole page - this will leave
any non-delalloc block intact and handle the iteration for us. As a side
effect one more place stops caring about buffer heads and we can remove the
xfs_check_page_type function entirely.
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>
xfs: use iomap for blocksize == PAGE_SIZE readpage and readpages
For file systems with a block size that equals the page size we never do
partial reads, so we can use the buffer_head-less iomap versions of
readpage and readpages without conflicting with the buffer_head structures
create later in write_begin.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/pti updates from Thomas Gleixner:
"Two small fixes correcting the handling of SSB mitigations on AMD
processors"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/bugs: Fix the AMD SSBD usage of the SPEC_CTRL MSR
x86/bugs: Update when to check for the LS_CFG SSBD mitigation
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
- Prevent an out-of-bounds access in mtrr_write()
- Break a circular dependency in the new hyperv IPI acceleration code
- Address the build breakage related to inline functions by enforcing
gnu_inline and explicitly bringing native_save_fl() out of line,
which also adds a set of _ARM_ARG macros which provide 32/64bit
safety.
- Initialize the shadow CR4 per cpu variable before using it.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mtrr: Don't copy out-of-bounds data in mtrr_write
x86/hyper-v: Fix the circular dependency in IPI enlightenment
x86/paravirt: Make native_save_fl() extern inline
x86/asm: Add _ASM_ARG* constants for argument registers to <asm/asm.h>
compiler-gcc.h: Add __attribute__((gnu_inline)) to all inline declarations
x86/mm/32: Initialize the CR4 shadow before __flush_tlb_all()