Commit Graph

240 Commits

Author SHA1 Message Date
Brian Foster
81ba8f3e94 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>
2018-07-11 22:26:16 -07:00
Brian Foster
f4a9cf97fa 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>
2018-07-11 22:26:15 -07:00
Brian Foster
3e3673e302 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>
2018-07-11 22:26:14 -07:00
Brian Foster
ff3edf255d 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>
2018-07-11 22:26:14 -07:00
Brian Foster
ccd9d91148 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>
2018-07-11 22:26:13 -07:00
Brian Foster
6e702a5dcb 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>
2018-07-11 22:26:12 -07:00
Brian Foster
32a9b7c65c 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>
2018-07-11 22:26:11 -07:00
Brian Foster
d76e6ce8ed 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>
2018-07-11 22:26:10 -07:00
Brian Foster
0bd6207f83 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>
2018-07-11 22:26:10 -07:00
Brian Foster
40d03ac6aa 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>
2018-07-11 22:26:09 -07:00
Christoph Hellwig
c3a2f9fff1 xfs: remove the now unused XFS_BMAPI_IGSTATE flag
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>
2018-07-11 22:26:01 -07:00
Darrick J. Wong
f62cb48e43 xfs: don't allow insert-range to shift extents past the maximum offset
Zorro Lang reports that generic/485 blows an assert on a filesystem with
512 byte blocks.  The test tries to fallocate a post-eof extent at the
maximum file size and calls insert range to shift the extents right by
two blocks.  On a 512b block filesystem this causes startoff to overflow
the 54-bit startoff field, leading to the assert.

Therefore, always check the rightmost extent to see if it would overflow
prior to invoking the insert range machinery.

Reported-by: zlang@redhat.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200137
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-06-24 11:56:36 -07:00
Dave Chinner
0703a8e1c1 xfs: replace do_mod with native operations
do_mod() is a hold-over from when we have different sizes for file
offsets and and other internal values for 40 bit XFS filesystems.
Hence depending on build flags variables passed to do_mod() could
change size. We no longer support those small format filesystems and
hence everything is of fixed size theses days, even on 32 bit
platforms.

As such, we can convert all the do_mod() callers to platform
optimised modulus operations as defined by linux/math64.h.
Individual conversions depend on the types of variables being used.

Signed-Off-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>
2018-06-08 10:07:52 -07:00
Dave Chinner
9bb54cb56a xfs: clean up MIN/MAX
Get rid of the MIN/MAX macros and just use the native min/max macros
directly in the XFS code.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-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>
2018-06-08 10:07:52 -07:00
Dave Chinner
0b61f8a407 xfs: convert to SPDX license tags
Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
	echo $f
	cat $f | awk -f hdr.awk > $f.new
	mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
	hdr = 1.0
	tag = "GPL-2.0"
	str = ""
}

/^ \* This program is free software/ {
	hdr = 2.0;
	next
}

/any later version./ {
	tag = "GPL-2.0+"
	next
}

/^ \*\// {
	if (hdr > 0.0) {
		print "// SPDX-License-Identifier: " tag
		print str
		print $0
		str=""
		hdr = 0.0
		next
	}
	print $0
	next
}

/^ \* / {
	if (hdr > 1.0)
		next
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
	next
}

/^ \*/ {
	if (hdr > 0.0)
		next
	print $0
	next
}

// {
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
}

END { }
$

Signed-off-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>
2018-06-06 14:17:53 -07:00
Darrick J. Wong
17ba2cc7b5 xfs: don't assert when reporting on-disk corruption while loading btree
Don't bother ASSERTing when we're already going to log and return the
corruption status.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-06-04 14:45:29 -07:00
Darrick J. Wong
7644bd988d xfs: teach xfs_bmapi_remap to accept some bmapi flags
Teach xfs_bmapi_remap how to map in unwritten extent and to skip rmap
updates.  This enables us to rebuild real and unwritten extents from the
rmapbt.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Darrick J. Wong
7cf199ba5a xfs: make xfs_bmapi_remapi work with attribute forks
Add a new flags argument to xfs_bmapi_remapi so that we can pass BMAPI
flags into the function.  This enables us to pass in BMAPI_ATTRFORK so
that we can remap things into the attribute fork.  Eventually the
online repair code will use this to rebuild attribute forks, so make it
non-static.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-15 18:12:50 -07:00
Brian Foster
4e529339af xfs: factor out nodiscard helpers
The changes to skip discards of speculative preallocation and
unwritten extents introduced several new wrapper functions through
the bunmapi -> extent free codepath to reduce churn in all of the
associated callers. In several cases, these wrappers simply toggle a
single flag to skip or not skip discards for the resulting blocks.

The explicit _nodiscard() wrappers for such an isolated set of
callers is a bit overkill. Kill off these wrappers and replace with
the calls to the underlying functions in the contexts that need to
control discard behavior. Retain the wrappers that preserve the
original calling conventions to serve the original purpose of
reducing code churn.

This is a refactoring patch and 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>
2018-05-15 17:57:05 -07:00
Darrick J. Wong
95eb308caa xfs: add BMAPI_NORMAP flag to perform block remapping without updating rmapbt
Add a new flag, XFS_BMAPI_NORMAP, which will perform file block
remapping without updating the rmapbt.  This will be used by the repair
code to reconstruct bmbts from the rmapbt, in which case we don't want
the rmapbt update.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-05-15 17:57:05 -07:00
Brian Foster
84ca484ecf xfs: don't discard on free of unwritten extents
Unwritten extents by definition have not been written to until they
are converted to normal written extents. If unwritten extents are
freed from a file, it is therefore guaranteed that the blocks have
not been written to since allocation (note that zero range punches
and reallocates blocks).

To cut down on online discards generated from workloads that make
use of preallocation, skip discards of extents if they are in the
unwritten state when the extent is freed.

Note that this optimization does not apply to log recovery, during
which all freed extents are discarded if online discard is enabled.
Also note that it may be possible for a filesystem crash to occur
after write completion of an unwritten extent but before unwritten
conversion such that the extent remains unwritten after log
recovery. Since this pseudo-inconsistency may already be possible
after a crash (consider writing to recently allocated blocks where
the allocation transaction is lost after a crash), this change
shouldn't introduce any fundamental limitations that don't already
exist. In short, on storage stacks where discards are important,
it's good practice to run an occasional fstrim even with online
discard enabled in the filesystem, particularly after a crash.

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>
2018-05-10 08:56:47 -07:00
Brian Foster
fcb762f5de xfs: add bmapi nodiscard flag
Freed extents are unconditionally discarded when online discard is
enabled. Define XFS_BMAPI_NODISCARD to allow callers to bypass
discards when unnecessary. For example, this will be useful for
eofblocks trimming.

This patch does not change behavior.

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>
2018-05-10 08:56:46 -07:00
Dave Chinner
e6631f8554 xfs: get rid of the log item descriptor
It's just a connector between a transaction and a log item. There's
a 1:1 relationship between a log item descriptor and a log item,
and a 1:1 relationship between a log item descriptor and a
transaction. Both relationships are created and terminated at the
same time, so why do we even have the descriptor?

Replace it with a specific list_head in the log item and a new
log item dirtied flag to replace the XFS_LID_DIRTY flag.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[darrick: fix up deferred agfl intent finish_item use of LID_DIRTY]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-10 08:56:46 -07:00
Darrick J. Wong
cec572561a xfs: bmap debugging should never panic the system
Don't panic() the system if the bmap records are garbage, just call
ASSERT which gives us the same backtrace but enables developers to
control if the system goes down or not.  This makes debugging with
generic/388 much easier because it won't reboot the machine midway
through a run just because btree_read_bufl returns EIO when the fs has
already shut down.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-05-09 10:04:02 -07:00
Eric Sandeen
2c4306f719 xfs: set format back to extents if xfs_bmap_extents_to_btree
If xfs_bmap_extents_to_btree fails in a mode where we call
xfs_iroot_realloc(-1) to de-allocate the root, set the
format back to extents.

Otherwise we can assume we can dereference ifp->if_broot
based on the XFS_DINODE_FMT_BTREE format, and crash.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199423
Signed-off-by: Eric Sandeen <sandeen@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>
2018-04-17 17:10:17 -07:00
Eric Sandeen
a1f69417c6 xfs: non-scrub - remove unused function parameters
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>
2018-04-09 10:23:42 -07:00
Darrick J. Wong
90a58f9571 xfs: refactor inode verifier error logging
Refactor some of the inode verifier failure logging call sites to use
the new xfs_inode_verifier_error method which dumps the offending buffer
as well as the code location of the failed check.  This trims the
output, makes it clearer to the admin that repair must be run, and gives
the developers more details to work from.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:07 -07:00
Darrick J. Wong
30b0984d91 xfs: refactor bmap record validation
Refactor the bmap validator into a more complete helper that looks for
extents that run off the end of the device, overflow into the next AG,
or have invalid flag states.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:07 -07:00
Darrick J. Wong
6d8a45ce29 xfs: don't screw up direct writes when freesp is fragmented
xfs_bmap_btalloc is given a range of file offset blocks that must be
allocated to some data/attr/cow fork.  If the fork has an extent size
hint associated with it, the request will be enlarged on both ends to
try to satisfy the alignment hint.  If free space is fragmentated,
sometimes we can allocate some blocks but not enough to fulfill any of
the requested range.  Since bmapi_allocate always trims the new extent
mapping to match the originally requested range, this results in
bmapi_write returning zero and no mapping.

The consequences of this vary -- buffered writes will simply re-call
bmapi_write until it can satisfy at least one block from the original
request.  Direct IO overwrites notice nmaps == 0 and return -ENOSPC
through the dio mechanism out to userspace with the weird result that
writes fail even when we have enough space because the ENOSPC return
overrides any partial write status.  For direct CoW writes the situation
was disastrous because nobody notices us returning an invalid zero-length
wrong-offset mapping to iomap and the write goes off into space.

Therefore, if free space is so fragmented that we managed to allocate
some space but not enough to map into even a single block of the
original allocation request range, we should break the alignment hint in
order to guarantee at least some forward progress for the direct write.
If we return a short allocation to iomap_apply it'll call back about the
remaining blocks.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-01-29 07:27:24 -08:00
Darrick J. Wong
4b4c1326fd xfs: treat CoW fork operations as delalloc for quota accounting
Since the CoW fork only exists in memory, it is incorrect to update the
on-disk quota block counts when we modify the CoW fork.  Unlike the data
fork, even real extents in the CoW fork are only delalloc-style
reservations (on-disk they're owned by the refcountbt) so they must not
be tracked in the on disk quota info.  Ensure the i_delayed_blks
accounting reflects this too.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-01-29 07:27:23 -08:00
Darrick J. Wong
751f3767c2 xfs: refactor accounting updates out of xfs_bmap_btalloc
Move all the inode and quota accounting updates out of xfs_bmap_btalloc
in preparation for fixing some quota accounting problems with copy on
write.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-01-29 07:27:23 -08:00
Shan Hai
6ca30729c2 xfs: bmap code cleanup
Remove the extent size hint and realtime inode relevant code from
the xfs_bmapi_reserve_delalloc since it is not called on the inode
with extent size hint set or on a realtime inode.

Signed-off-by: Shan Hai <shan.hai@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-01-29 07:27:22 -08:00
Darrick J. Wong
be78ff0e72 xfs: recheck reflink / dirty page status before freeing CoW reservations
Eryu Guan reported seeing occasional hangs when running generic/269 with
a new fsstress that supports clonerange/deduperange.  The cause of this
hang is an infinite loop when we convert the CoW fork extents from
unwritten to real just prior to writing the pages out; the infinite
loop happens because there's nothing in the CoW fork to convert, and so
it spins forever.

The fundamental issue here is that when we go to perform these CoW fork
conversions, we're supposed to have an extent waiting for us, but the
low space CoW reaper has snuck in and blown them away!  There are four
conditions that can dissuade the reaper from touching our file -- no
reflink iflag; dirty page cache; writeback in progress; or directio in
progress.  We check the four conditions prior to taking the locks, but
we neglect to recheck them once we have the locks, which is how we end
up whacking the writeback that's in progress.

Therefore, refactor the four checks into a helper function and call it
once again once we have the locks to make sure we really want to reap
the inode.  While we're at it, add an ASSERT for this weird condition so
that we'll fail noisily if we ever screw this up again.

Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Tested-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-01-17 21:00:47 -08:00
Darrick J. Wong
59f6fec3bd xfs: remove XFS_FSB_SANITY_CHECK
We already have a function to verify fsb pointers, so get rid of the
last users of the (less robust) macro.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2018-01-08 10:54:45 -08:00
Darrick J. Wong
8c57b88637 xfs: account for null transactions in bunmapi
In e1a4e37cc7 ("xfs: try to avoid blowing out the transaction
reservation when bunmaping a shared extent"), we try to constrain the
amount of real extents we unmap from the data fork in a given call so
that we don't blow out transaction reservations.

However, not all bunmapi operations require a transaction -- if we're
only removing a delalloc extent, no transaction is needed, so we have to
code against that.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-12-14 09:20:10 -08:00
Eric Sandeen
d41c6172bd xfs: fix leaks on corruption errors in xfs_bmap.c
Use _GOTO instead of _RETURN so we can free the allocated
cursor on error.

Fixes: bf80628 ("xfs: remove xfs_bmse_shift_one")
Fixes-coverity-id: 1423813, 1423676
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>
2017-11-28 08:57:11 -08:00
Christoph Hellwig
dac9c9b137 xfs: pass struct xfs_bmbt_irec to xfs_bmbt_validate_extent
This removed an unaligned load per extent, as well as the manual poking
into the on-disk extent format.

Signed-off-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>
2017-11-06 11:53:41 -08:00
Christoph Hellwig
c38ccf5990 xfs: remove the nr_extents argument to xfs_iext_remove
We only have two places that remove 2 extents at the same time, so unroll
the loop there.

Signed-off-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>
2017-11-06 11:53:41 -08:00
Christoph Hellwig
0254c2f253 xfs: remove the nr_extents argument to xfs_iext_insert
We only have two places that insert 2 extents at the same time, so unroll
the loop there.

Signed-off-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>
2017-11-06 11:53:41 -08:00
Christoph Hellwig
6bdcf26ade xfs: use a b+tree for the in-core extent list
Replace the current linear list and the indirection array for the in-core
extent list with a b+tree to avoid the need for larger memory allocations
for the indirection array when lots of extents are present.  The current
extent list implementations leads to heavy pressure on the memory
allocator when modifying files with a high extent count, and can lead
to high latencies because of that.

The replacement is a b+tree with a few quirks.  The leaf nodes directly
store the extent record in two u64 values.  The encoding is a little bit
different from the existing in-core extent records so that the start
offset and length which are required for lookups can be retreived with
simple mask operations.  The inner nodes store a 64-bit key containing
the start offset in the first half of the node, and the pointers to the
next lower level in the second half.  In either case we walk the node
from the beginninig to the end and do a linear search, as that is more
efficient for the low number of cache lines touched during a search
(2 for the inner nodes, 4 for the leaf nodes) than a binary search.
We store termination markers (zero length for the leaf nodes, an
otherwise impossible high bit for the inner nodes) to terminate the key
list / records instead of storing a count to use the available cache
lines as efficiently as possible.

One quirk of the algorithm is that while we normally split a node half and
half like usual btree implementations we just spill over entries added at
the very end of the list to a new node on its own.  This means we get a
100% fill grade for the common cases of bulk insertion when reading an
inode into memory, and when only sequentially appending to a file.  The
downside is a slightly higher chance of splits on the first random
insertions.

Both insert and removal manually recurse into the lower levels, but
the bulk deletion of the whole tree is still implemented as a recursive
function call, although one limited by the overall depth and with very
little stack usage in every iteration.

For the first few extents we dynamically grow the list from a single
extent to the next powers of two until we have a first full leaf block
and that building the actual tree.

The code started out based on the generic lib/btree.c code from Joern
Engel based on earlier work from Peter Zijlstra, but has since been
rewritten beyond recognition.

Signed-off-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>
2017-11-06 11:53:41 -08:00
Christoph Hellwig
b121459c7a xfs: simplify xfs_reflink_convert_cow
Instead of looking up extents to convert and calling xfs_bmapi_write on
each of them just let xfs_bmapi_write handle the full range.  To make
this robust add a new XFS_BMAPI_CONVERT_ONLY that only converts ranges
and never allocates blocks.

[darrick: shorten the stringified CONVERT_ONLY trace flag]

Signed-off-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>
2017-11-06 11:53:40 -08:00
Christoph Hellwig
b2b1712a64 xfs: introduce the xfs_iext_cursor abstraction
Add a new xfs_iext_cursor structure to hide the direct extent map
index manipulations. In addition to the existing lookup/get/insert/
remove and update routines new primitives to get the first and last
extent cursor, as well as moving up and down by one extent are
provided.  Also new are convenience to increment/decrement the
cursor and retreive the new extent, as well as to peek into the
previous/next extent without updating the cursor and last but not
least a macro to iterate over all extents in a fork.

[darrick: rename for_each_iext to for_each_xfs_iext]

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>
2017-11-06 11:53:40 -08:00
Christoph Hellwig
906abed501 xfs: iterate over extents in xfs_bmap_extents_to_btree
This actually makes the function very slightly less efficient for now as we
detour through the expanded irect format between the in-core extent format
and the on-disk one instead of just endian swapping them.  But with the
incore extent btree the in-core one will use a different format and the
representation will be entirely hidden.

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>
2017-11-06 11:53:40 -08:00
Christoph Hellwig
f36bc228e1 xfs: pass an on-disk extent to xfs_bmbt_validate_extent
This prepares for getting rid of the current in-memory extent format.
At the end of the series we will change the calling convention again
to pass the xfs_bmbt_irec structure once it is available everywhere.

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>
2017-11-06 11:53:39 -08:00
Christoph Hellwig
4263036100 xfs: treat idx as a cursor in xfs_bmap_collapse_extents
Stop poking before and after the index and just increment or decrement
it while doing our operations on it to prepare for a new extent list
implementation.

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>
2017-11-06 11:53:39 -08:00
Christoph Hellwig
657fcb2336 xfs: treat idx as a cursor in xfs_bmap_del_extent_*
Stop poking before and after the index and just increment or decrement
it while doing our operations on it to prepare for a new extent list
implementation.

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>
2017-11-06 11:53:39 -08:00
Christoph Hellwig
a681847796 xfs: treat idx as a cursor in xfs_bmap_add_extent_unwritten_real
Stop poking before and after the index and just increment or decrement
it while doing our operations on it to prepare for a new extent list
implementation.

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>
2017-11-06 11:53:39 -08:00
Christoph Hellwig
1d2e0089e1 xfs: treat idx as a cursor in xfs_bmap_add_extent_hole_real
Stop poking before and after the index and just increment or decrement
it while doing our operations on it to prepare for a new extent list
implementation.

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>
2017-11-06 11:53:39 -08:00
Christoph Hellwig
41d196f439 xfs: treat idx as a cursor in xfs_bmap_add_extent_hole_delay
Stop poking before and after the index and just increment or decrement
it while doing our operations on it to prepare for a new extent list
implementation.

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>
2017-11-06 11:53:38 -08:00
Christoph Hellwig
0d045540ed xfs: treat idx as a cursor in xfs_bmap_add_extent_delay_real
Stop poking before and after the index and just increment or decrement
it while doing our operations on it to prepare for a new extent list
implementation.

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>
2017-11-06 11:53:38 -08:00