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1370 commits

Author SHA1 Message Date
Dave Chinner
0fe0bbe00a xfs: bunmapi has unnecessary AG lock ordering issues
large directory block size operations are assert failing because
xfs_bunmapi() is not completely removing fragmented directory blocks
like so:

XFS: Assertion failed: done, file: fs/xfs/libxfs/xfs_dir2.c, line: 677
....
Call Trace:
 xfs_dir2_shrink_inode+0x1a8/0x210
 xfs_dir2_block_to_sf+0x2ae/0x410
 xfs_dir2_block_removename+0x21a/0x280
 xfs_dir_removename+0x195/0x1d0
 xfs_rename+0xb79/0xc50
 ? avc_has_perm+0x8d/0x1a0
 ? avc_has_perm_noaudit+0x9a/0x120
 xfs_vn_rename+0xdb/0x150
 vfs_rename+0x719/0xb50
 ? __lookup_hash+0x6a/0xa0
 do_renameat2+0x413/0x5e0
 __x64_sys_rename+0x45/0x50
 do_syscall_64+0x3a/0x70
 entry_SYSCALL_64_after_hwframe+0x44/0xae

We are aborting the bunmapi() pass because of this specific chunk of
code:

                /*
                 * Make sure we don't touch multiple AGF headers out of order
                 * in a single transaction, as that could cause AB-BA deadlocks.
                 */
                if (!wasdel && !isrt) {
                        agno = XFS_FSB_TO_AGNO(mp, del.br_startblock);
                        if (prev_agno != NULLAGNUMBER && prev_agno > agno)
                                break;
                        prev_agno = agno;
                }

This is designed to prevent deadlocks in AGF locking when freeing
multiple extents by ensuring that we only ever lock in increasing
AG number order. Unfortunately, this also violates the "bunmapi will
always succeed" semantic that some high level callers depend on,
such as xfs_dir2_shrink_inode(), xfs_da_shrink_inode() and
xfs_inactive_symlink_rmt().

This AG lock ordering was introduced back in 2017 to fix deadlocks
triggered by generic/299 as reported here:

https://lore.kernel.org/linux-xfs/800468eb-3ded-9166-20a4-047de8018582@gmail.com/

This codebase is old enough that it was before we were defering all
AG based extent freeing from within xfs_bunmapi(). THat is, we never
actually lock AGs in xfs_bunmapi() any more - every non-rt based
extent free is added to the defer ops list, as is all BMBT block
freeing. And RT extents are not RT based, so there's no lock
ordering issues associated with them.

Hence this AGF lock ordering code is both broken and dead. Let's
just remove it so that the large directory block code works reliably
again.

Tested against xfs/538 and generic/299 which is the original test
that exposed the deadlocks that this code fixed.

Fixes: 5b094d6dac ("xfs: fix multi-AG deadlock in xfs_bunmapi")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-05-27 08:11:24 -07:00
Dave Chinner
991c2c5980 xfs: btree format inode forks can have zero extents
xfs/538 is assert failing with this trace when testing with
directory block sizes of 64kB:

XFS: Assertion failed: !xfs_need_iread_extents(ifp), file: fs/xfs/libxfs/xfs_bmap.c, line: 608
....
Call Trace:
 xfs_bmap_btree_to_extents+0x2a9/0x470
 ? kmem_cache_alloc+0xe7/0x220
 __xfs_bunmapi+0x4ca/0xdf0
 xfs_bunmapi+0x1a/0x30
 xfs_dir2_shrink_inode+0x71/0x210
 xfs_dir2_block_to_sf+0x2ae/0x410
 xfs_dir2_block_removename+0x21a/0x280
 xfs_dir_removename+0x195/0x1d0
 xfs_remove+0x244/0x460
 xfs_vn_unlink+0x53/0xa0
 ? selinux_inode_unlink+0x13/0x20
 vfs_unlink+0x117/0x220
 do_unlinkat+0x1a2/0x2d0
 __x64_sys_unlink+0x42/0x60
 do_syscall_64+0x3a/0x70
 entry_SYSCALL_64_after_hwframe+0x44/0xae

This is a check to ensure that the extents have been read into
memory before we are doing a ifork btree manipulation. This assert
is bogus in the above case.

We have a fragmented directory block that has more extents in it
than can fit in extent format, so the inode data fork is in btree
format. xfs_dir2_shrink_inode() asks to remove all remaining 16
filesystem blocks from the inode so it can convert to short form,
and __xfs_bunmapi() removes all the extents. We now have a data fork
in btree format but have zero extents in the fork. This incorrectly
trips the xfs_need_iread_extents() assert because it assumes that an
empty extent btree means the extent tree has not been read into
memory yet. This is clearly not the case with xfs_bunmapi(), as it
has an explicit call to xfs_iread_extents() in it to pull the
extents into memory before it starts unmapping.

Also, the assert directly after this bogus one is:

	ASSERT(ifp->if_format == XFS_DINODE_FMT_BTREE);

Which covers the context in which it is legal to call
xfs_bmap_btree_to_extents just fine. Hence we should just remove the
bogus assert as it is clearly wrong and causes a regression.

The returns the test behaviour to the pre-existing assert failure in
xfs_dir2_shrink_inode() that indicates xfs_bunmapi() has failed to
remove all the extents in the range it was asked to unmap.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-05-27 08:11:24 -07:00
Darrick J. Wong
603f000b15 xfs: validate extsz hints against rt extent size when rtinherit is set
The RTINHERIT bit can be set on a directory so that newly created
regular files will have the REALTIME bit set to store their data on the
realtime volume.  If an extent size hint (and EXTSZINHERIT) are set on
the directory, the hint will also be copied into the new file.

As pointed out in previous patches, for realtime files we require the
extent size hint be an integer multiple of the realtime extent, but we
don't perform the same validation on a directory with both RTINHERIT and
EXTSZINHERIT set, even though the only use-case of that combination is
to propagate extent size hints into new realtime files.  This leads to
inode corruption errors when the bad values are propagated.

Because there may be existing filesystems with such a configuration, we
cannot simply amend the inode verifier to trip on these directories and
call it a day because that will cause previously "working" filesystems
to start throwing errors abruptly.  Note that it's valid to have
directories with rtinherit set even if there is no realtime volume, in
which case the problem does not manifest because rtinherit is ignored if
there's no realtime device; and it's possible that someone set the flag,
crashed, repaired the filesystem (which clears the hint on the realtime
file) and continued.

Therefore, mitigate this issue in several ways: First, if we try to
write out an inode with both rtinherit/extszinherit set and an unaligned
extent size hint, turn off the hint to correct the error.  Second, if
someone tries to misconfigure a directory via the fssetxattr ioctl, fail
the ioctl.  Third, reverify both extent size hint values when we
propagate heritable inode attributes from parent to child, to prevent
misconfigurations from spreading.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-05-24 18:01:04 -07:00
Darrick J. Wong
6b69e48589 xfs: standardize extent size hint validation
While chasing a bug involving invalid extent size hints being propagated
into newly created realtime files, I noticed that the xfs_ioctl_setattr
checks for the extent size hints weren't the same as the ones now
encoded in libxfs and used for validation in repair and mkfs.

Because the checks in libxfs are more stringent than the ones in the
ioctl, it's possible for a live system to set inode flags that
immediately result in corruption warnings.  Specifically, it's possible
to set an extent size hint on an rtinherit directory without checking if
the hint is aligned to the realtime extent size, which makes no sense
since that combination is used only to seed new realtime files.

Replace the open-coded and inadequate checks with the libxfs verifier
versions and update the code comments a bit.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-05-24 18:01:04 -07:00
Darrick J. Wong
0f9342513c xfs: check free AG space when making per-AG reservations
The new online shrink code exposed a gap in the per-AG reservation
code, which is that we only return ENOSPC to callers if the entire fs
doesn't have enough free blocks.  Except for debugging mode, the
reservation init code doesn't ever check that there's enough free space
in that AG to cover the reservation.

Not having enough space is not considered an immediate fatal error that
requires filesystem offlining because (a) it's shouldn't be possible to
wind up in that state through normal file operations and (b) even if
one did, freeing data blocks would recover the situation.

However, online shrink now needs to know if shrinking would not leave
enough space so that it can abort the shrink operation.  Hence we need
to promote this assertion into an actual error return.

Observed by running xfs/168 with a 1k block size, though in theory this
could happen with any configuration.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2021-05-24 18:01:04 -07:00
Darrick J. Wong
e3c2b04747 xfs: restore old ioctl definitions
These ioctl definitions in xfs_fs.h are part of the userspace ABI and
were mistakenly removed during the 5.13 merge window.

Fixes: 9fefd5db08 ("xfs: convert to fileattr")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-05-20 08:31:22 -07:00
Linus Torvalds
af120709b1 More new code for 5.13:
- Rename the log timestamp struct.
 - Remove broken transaction counter debugging that wasn't working
   correctly on very old filesystems.
 - Various fixes to make pre-lazysbcount filesystems work properly again.
 - Fix a free space accounting problem where we neglected to consider
   free space btree blocks that track metadata reservation space when
   deciding whether or not to allow caller to reserve space for
   a metadata update.
 - Fix incorrect pagecache clearing behavior during FUNSHARE ops.
 - Don't allow log writes if the data device is readonly.
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Merge tag 'xfs-5.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull more xfs updates from Darrick Wong:
 "Except for the timestamp struct renaming patches, everything else in
  here are bug fixes:

   - Rename the log timestamp struct.

   - Remove broken transaction counter debugging that wasn't working
     correctly on very old filesystems.

   - Various fixes to make pre-lazysbcount filesystems work properly
     again.

   - Fix a free space accounting problem where we neglected to consider
     free space btree blocks that track metadata reservation space when
     deciding whether or not to allow caller to reserve space for a
     metadata update.

   - Fix incorrect pagecache clearing behavior during FUNSHARE ops.

   - Don't allow log writes if the data device is readonly"

* tag 'xfs-5.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: don't allow log writes if the data device is readonly
  xfs: fix xfs_reflink_unshare usage of filemap_write_and_wait_range
  xfs: set aside allocation btree blocks from block reservation
  xfs: introduce in-core global counter of allocbt blocks
  xfs: unconditionally read all AGFs on mounts with perag reservation
  xfs: count free space btree blocks when scrubbing pre-lazysbcount fses
  xfs: update superblock counters correctly for !lazysbcount
  xfs: don't check agf_btreeblks on pre-lazysbcount filesystems
  xfs: remove obsolete AGF counter debugging
  xfs: rename struct xfs_legacy_ictimestamp
  xfs: rename xfs_ictimestamp_t
2021-05-06 23:46:46 -07:00
Linus Torvalds
d2b6f8a179 New code for 5.13:
- Various minor fixes in online scrub.
 - Prevent metadata files from being automatically inactivated.
 - Validate btree heights by the computed per-btree limits.
 - Don't warn about remounting with deprecated mount options.
 - Initialize attr forks at create time if we suspect we're going to need
   to store them.
 - Reduce memory reallocation workouts in the logging code.
 - Fix some theoretical math calculation errors in logged buffers that
   span multiple discontig memory ranges but contiguous ondisk regions.
 - Speedups in dirty buffer bitmap handling.
 - Make type verifier functions more inline-happy to reduce overhead.
 - Reduce debug overhead in directory checking code.
 - Many many typo fixes.
 - Begin to handle the permanent loss of the very end of a filesystem.
 - Fold struct xfs_icdinode into xfs_inode.
 - Deprecate the long defunct BMV_IF_NO_DMAPI_READ from the bmapx ioctl.
 - Remove a broken directory block format check from online scrub.
 - Fix a bug where we could produce an unnecessarily tall data fork btree
   when creating an attr fork.
 - Fix scrub and readonly remounts racing.
 - Fix a writeback ioend log deadlock problem by dropping the behavior
   where we could preallocate a setfilesize transaction.
 - Fix some bugs in the new extent count checking code.
 - Fix some bugs in the attr fork preallocation code.
 - Refactor if_flags out of the incore inode fork data structure.
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Merge tag 'xfs-5.13-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Darrick Wong:
 "The notable user-visible addition this cycle is ability to remove
  space from the last AG in a filesystem. This is the first of many
  changes needed for full-fledged support for shrinking a filesystem.
  Still needed are (a) the ability to reorganize files and metadata away
  from the end of the fs; (b) the ability to remove entire allocation
  groups; (c) shrink support for realtime volumes; and (d) thorough
  testing of (a-c).

  There are a number of performance improvements in this code drop: Dave
  streamlined various parts of the buffer logging code and reduced the
  cost of various debugging checks, and added the ability to pre-create
  the xattr structures while creating files. Brian eliminated
  transaction reservations that were being held across writeback (thus
  reducing livelock potential.

  Other random pieces: Pavel fixed the repetitve warnings about
  deprecated mount options, I fixed online fsck to behave itself when a
  readonly remount comes in during scrub, and refactored various other
  parts of that code, Christoph contributed a lot of refactoring this
  cycle. The xfs_icdinode structure has been absorbed into the (incore)
  xfs_inode structure, and the format and flags handling around
  xfs_inode_fork structures has been simplified. Chandan provided a
  number of fixes for extent count overflow related problems that have
  been shaken out by debugging knobs added during 5.12.

  Summary:

   - Various minor fixes in online scrub.

   - Prevent metadata files from being automatically inactivated.

   - Validate btree heights by the computed per-btree limits.

   - Don't warn about remounting with deprecated mount options.

   - Initialize attr forks at create time if we suspect we're going to
     need to store them.

   - Reduce memory reallocation workouts in the logging code.

   - Fix some theoretical math calculation errors in logged buffers that
     span multiple discontig memory ranges but contiguous ondisk
     regions.

   - Speedups in dirty buffer bitmap handling.

   - Make type verifier functions more inline-happy to reduce overhead.

   - Reduce debug overhead in directory checking code.

   - Many many typo fixes.

   - Begin to handle the permanent loss of the very end of a filesystem.

   - Fold struct xfs_icdinode into xfs_inode.

   - Deprecate the long defunct BMV_IF_NO_DMAPI_READ from the bmapx
     ioctl.

   - Remove a broken directory block format check from online scrub.

   - Fix a bug where we could produce an unnecessarily tall data fork
     btree when creating an attr fork.

   - Fix scrub and readonly remounts racing.

   - Fix a writeback ioend log deadlock problem by dropping the behavior
     where we could preallocate a setfilesize transaction.

   - Fix some bugs in the new extent count checking code.

   - Fix some bugs in the attr fork preallocation code.

   - Refactor if_flags out of the incore inode fork data structure"

* tag 'xfs-5.13-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (77 commits)
  xfs: remove xfs_quiesce_attr declaration
  xfs: remove XFS_IFEXTENTS
  xfs: remove XFS_IFINLINE
  xfs: remove XFS_IFBROOT
  xfs: only look at the fork format in xfs_idestroy_fork
  xfs: simplify xfs_attr_remove_args
  xfs: rename and simplify xfs_bmap_one_block
  xfs: move the XFS_IFEXTENTS check into xfs_iread_extents
  xfs: drop unnecessary setfilesize helper
  xfs: drop unused ioend private merge and setfilesize code
  xfs: open code ioend needs workqueue helper
  xfs: drop submit side trans alloc for append ioends
  xfs: fix return of uninitialized value in variable error
  xfs: get rid of the ip parameter to xchk_setup_*
  xfs: fix scrub and remount-ro protection when running scrub
  xfs: move the check for post-EOF mappings into xfs_can_free_eofblocks
  xfs: move the xfs_can_free_eofblocks call under the IOLOCK
  xfs: precalculate default inode attribute offset
  xfs: default attr fork size does not handle device inodes
  xfs: inode fork allocation depends on XFS_IFEXTENT flag
  ...
2021-04-29 10:43:51 -07:00
Brian Foster
16eaab839a xfs: introduce in-core global counter of allocbt blocks
Introduce an in-core counter to track the sum of all allocbt blocks
used by the filesystem. This value is currently tracked per-ag via
the ->agf_btreeblks field in the AGF, which also happens to include
rmapbt blocks. A global, in-core count of allocbt blocks is required
to identify the subset of global ->m_fdblocks that consists of
unavailable blocks currently used for allocation btrees. To support
this calculation at block reservation time, construct a similar
global counter for allocbt blocks, populate it on first read of each
AGF and update it as allocbt blocks are used and released.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-29 07:45:44 -07:00
Brian Foster
2675ad3890 xfs: unconditionally read all AGFs on mounts with perag reservation
perag reservation is enabled at mount time on a per AG basis. The
upcoming change to set aside allocbt blocks from block reservation
requires a populated allocbt counter as soon as possible after mount
to be fully effective against large perag reservations. Therefore as
a preparation step, initialize the pagf on all mounts where at least
one reservation is active. Note that this already occurs to some
degree on most default format filesystems as reservation requirement
calculations already depend on the AGF or AGI, depending on the
reservation type.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-29 07:45:44 -07:00
Dave Chinner
6543990a16 xfs: update superblock counters correctly for !lazysbcount
Keep the mount superblock counters up to date for !lazysbcount
filesystems so that when we log the superblock they do not need
updating in any way because they are already correct.

It's found by what Zorro reported:
1. mkfs.xfs -f -l lazy-count=0 -m crc=0 $dev
2. mount $dev $mnt
3. fsstress -d $mnt -p 100 -n 1000 (maybe need more or less io load)
4. umount $mnt
5. xfs_repair -n $dev
and I've seen no problem with this patch.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reported-by: Zorro Lang <zlang@redhat.com>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-04-29 07:44:18 -07:00
Darrick J. Wong
1aec7c3d05 xfs: remove obsolete AGF counter debugging
In commit f8f2835a9c we changed the behavior of XFS to use EFIs to
remove blocks from an overfilled AGFL because there were complaints
about transaction overruns that stemmed from trying to free multiple
blocks in a single transaction.

Unfortunately, that commit missed a subtlety in the debug-mode
transaction accounting when a realtime volume is attached.  If a
realtime file undergoes a data fork mapping change such that realtime
extents are allocated (or freed) in the same transaction that a data
device block is also allocated (or freed), we can trip a debugging
assertion.  This can happen (for example) if a realtime extent is
allocated and it is necessary to reshape the bmbt to hold the new
mapping.

When we go to allocate a bmbt block from an AG, the first thing the data
device block allocator does is ensure that the freelist is the proper
length.  If the freelist is too long, it will trim the freelist to the
proper length.

In debug mode, trimming the freelist calls xfs_trans_agflist_delta() to
record the decrement in the AG free list count.  Prior to f8f28 we would
put the free block back in the free space btrees in the same
transaction, which calls xfs_trans_agblocks_delta() to record the
increment in the AG free block count.  Since AGFL blocks are included in
the global free block count (fdblocks), there is no corresponding
fdblocks update, so the AGFL free satisfies the following condition in
xfs_trans_apply_sb_deltas:

	/*
	 * Check that superblock mods match the mods made to AGF counters.
	 */
	ASSERT((tp->t_fdblocks_delta + tp->t_res_fdblocks_delta) ==
	       (tp->t_ag_freeblks_delta + tp->t_ag_flist_delta +
		tp->t_ag_btree_delta));

The comparison here used to be: (X + 0) == ((X+1) + -1 + 0), where X is
the number blocks that were allocated.

After commit f8f28 we defer the block freeing to the next chained
transaction, which means that the calls to xfs_trans_agflist_delta and
xfs_trans_agblocks_delta occur in separate transactions.  The (first)
transaction that shortens the free list trips on the comparison, which
has now become:

(X + 0) == ((X) + -1 + 0)

because we haven't freed the AGFL block yet; we've only logged an
intention to free it.  When the second transaction (the deferred free)
commits, it will evaluate the expression as:

(0 + 0) == (1 + 0 + 0)

and trip over that in turn.

At this point, the astute reader may note that the two commits tagged by
this patch have been in the kernel for a long time but haven't generated
any bug reports.  How is it that the author became aware of this bug?

This originally surfaced as an intermittent failure when I was testing
realtime rmap, but a different bug report by Zorro Lang reveals the same
assertion occuring on !lazysbcount filesystems.

The common factor to both reports (and why this problem wasn't
previously reported) becomes apparent if we consider when
xfs_trans_apply_sb_deltas is called by __xfs_trans_commit():

	if (tp->t_flags & XFS_TRANS_SB_DIRTY)
		xfs_trans_apply_sb_deltas(tp);

With a modern lazysbcount filesystem, transactions update only the
percpu counters, so they don't need to set XFS_TRANS_SB_DIRTY, hence
xfs_trans_apply_sb_deltas is rarely called.

However, updates to the count of free realtime extents are not part of
lazysbcount, so XFS_TRANS_SB_DIRTY will be set on transactions adding or
removing data fork mappings to realtime files; similarly,
XFS_TRANS_SB_DIRTY is always set on !lazysbcount filesystems.

Dave mentioned in response to an earlier version of this patch:

"IIUC, what you are saying is that this debug code is simply not
exercised in normal testing and hasn't been for the past decade?  And it
still won't be exercised on anything other than realtime device testing?

"...it was debugging code from 1994 that was largely turned into dead
code when lazysbcounters were introduced in 2007. Hence I'm not sure it
holds any value anymore."

This debugging code isn't especially helpful - you can modify the
flcount on one AG and the freeblks of another AG, and it won't trigger.
Add the fact that nobody noticed for a decade, and let's just get rid of
it (and start testing realtime :P).

This bug was found by running generic/051 on either a V4 filesystem
lacking lazysbcount; or a V5 filesystem with a realtime volume.

Cc: bfoster@redhat.com, zlang@redhat.com
Fixes: f8f2835a9c ("xfs: defer agfl block frees when dfops is available")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-04-29 07:44:18 -07:00
Christoph Hellwig
732de7dbdb xfs: rename struct xfs_legacy_ictimestamp
Rename struct xfs_legacy_ictimestamp to struct xfs_log_legacy_timestamp
as it is a type used for logging timestamps with no relationship to the
in-core inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-22 18:29:25 -07:00
Christoph Hellwig
6fc277c7c9 xfs: rename xfs_ictimestamp_t
Rename xfs_ictimestamp_t to xfs_log_timestamp_t as it is a type used
for logging timestamps with no relationship to the in-core inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-22 18:29:17 -07:00
Christoph Hellwig
b2197a36c0 xfs: remove XFS_IFEXTENTS
The in-memory XFS_IFEXTENTS is now only used to check if an inode with
extents still needs the extents to be read into memory before doing
operations that need the extent map.  Add a new xfs_need_iread_extents
helper that returns true for btree format forks that do not have any
entries in the in-memory extent btree, and use that instead of checking
the XFS_IFEXTENTS flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-15 09:35:51 -07:00
Christoph Hellwig
0779f4a68d xfs: remove XFS_IFINLINE
Just check for an inline format fork instead of the using the equivalent
in-memory XFS_IFINLINE flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-15 09:35:51 -07:00
Christoph Hellwig
ac1e067211 xfs: remove XFS_IFBROOT
Just check for a btree format fork instead of the using the equivalent
in-memory XFS_IFBROOT flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-15 09:35:51 -07:00
Christoph Hellwig
0eba048dd3 xfs: only look at the fork format in xfs_idestroy_fork
Stop using the XFS_IFEXTENTS flag, and instead switch on the fork format
in xfs_idestroy_fork to decide how to cleanup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-15 09:35:50 -07:00
Christoph Hellwig
605e74e292 xfs: simplify xfs_attr_remove_args
Directly return from the subfunctions and avoid the error variable.  Also
remove the not really needed dp local variable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-15 09:35:50 -07:00
Christoph Hellwig
2ac131df03 xfs: rename and simplify xfs_bmap_one_block
xfs_bmap_one_block is only called for the attribute fork.  Move it to
xfs_attr.c, drop the unused whichfork argument and code only executed for
the data fork and rename the result to xfs_attr_is_leaf.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-15 09:35:50 -07:00
Christoph Hellwig
862a804aae xfs: move the XFS_IFEXTENTS check into xfs_iread_extents
Move the XFS_IFEXTENTS check from the callers into xfs_iread_extents to
simplify the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-15 09:35:50 -07:00
Miklos Szeredi
9fefd5db08 xfs: convert to fileattr
Use the fileattr API to let the VFS handle locking, permission checking and
conversion.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Darrick J. Wong <djwong@kernel.org>
2021-04-12 15:04:29 +02:00
Colin Ian King
3b6dd9a9ae xfs: fix return of uninitialized value in variable error
A previous commit removed a call to xfs_attr3_leaf_read that
assigned an error return code to variable error. We now have
a few early error return paths to label 'out' that return
error if error is set; however error now is uninitialized
so potentially garbage is being returned.  Fix this by setting
error to zero to restore the original behaviour where error
was zero at the label 'restart'.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: 07120f1abd ("xfs: Add xfs_has_attr and subroutines")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-09 10:27:34 -07:00
Dave Chinner
b2941046ea xfs: precalculate default inode attribute offset
Default attr fork offset is based on inode size, so is a fixed
geometry parameter of the inode. Move it to the xfs_ino_geometry
structure and stop calculating it on every call to
xfs_default_attroffset().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
2021-04-07 14:37:07 -07:00
Dave Chinner
683ec9ba88 xfs: default attr fork size does not handle device inodes
Device inodes have a non-default data fork size of 8 bytes
as checked/enforced by xfs_repair. xfs_default_attroffset() doesn't
handle this, so lets do a minor refactor so it does.

Fixes: e6a688c332 ("xfs: initialise attr fork on inode create")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
2021-04-07 14:37:07 -07:00
Chandan Babu R
b6785e279d xfs: Use struct xfs_bmdr_block instead of struct xfs_btree_block to calculate root node size
The incore data fork of an inode stores the bmap btree root node as 'struct
xfs_btree_block'. However, the ondisk version of the inode stores the bmap
btree root node as a 'struct xfs_bmdr_block'.

xfs_bmap_add_attrfork_btree() checks if the btree root node fits inside the
data fork of the inode. However, it incorrectly uses 'struct xfs_btree_block'
to compute the size of the bmap btree root node. Since size of 'struct
xfs_btree_block' is larger than that of 'struct xfs_bmdr_block',
xfs_bmap_add_attrfork_btree() could end up unnecessarily demoting the current
root node as the child of newly allocated root node.

This commit optimizes space usage by modifying xfs_bmap_add_attrfork_btree()
to use 'struct xfs_bmdr_block' to check if the bmap btree root node fits
inside the data fork of the inode.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:06 -07:00
Anthony Iliopoulos
fcb62c2803 xfs: deprecate BMV_IF_NO_DMAPI_READ flag
Use of the flag has had no effect since kernel commit 288699feca
("xfs: drop dmapi hooks"), which removed all dmapi related code, so
deprecate it.

Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:06 -07:00
Christoph Hellwig
e98d5e882b xfs: move the di_crtime field to struct xfs_inode
Move the crtime field from struct xfs_icdinode into stuct xfs_inode and
remove the now entirely unused struct xfs_icdinode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig
3e09ab8fdc xfs: move the di_flags2 field to struct xfs_inode
In preparation of removing the historic icinode struct, move the flags2
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig
db07349da2 xfs: move the di_flags field to struct xfs_inode
In preparation of removing the historic icinode struct, move the flags
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig
7821ea302d xfs: move the di_forkoff field to struct xfs_inode
In preparation of removing the historic icinode struct, move the
forkoff field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig
ee7b83fd36 xfs: use a union for i_cowextsize and i_flushiter
The i_cowextsize field is only used for v3 inodes, and the i_flushiter
field is only used for v1/v2 inodes.  Use a union to pack the inode a
littler better after adding a few missing guards around their usage.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:05 -07:00
Christoph Hellwig
965e0a1ad2 xfs: move the di_flushiter field to struct xfs_inode
In preparation of removing the historic icinode struct, move the
flushiter field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:04 -07:00
Christoph Hellwig
b33ce57d3e xfs: move the di_cowextsize field to struct xfs_inode
In preparation of removing the historic icinode struct, move the
cowextsize field into the containing xfs_inode structure.  Also
switch to use the xfs_extlen_t instead of a uint32_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:04 -07:00
Christoph Hellwig
031474c28a xfs: move the di_extsize field to struct xfs_inode
In preparation of removing the historic icinode struct, move the extsize
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:04 -07:00
Christoph Hellwig
6e73a545f9 xfs: move the di_nblocks field to struct xfs_inode
In preparation of removing the historic icinode struct, move the nblocks
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig
13d2c10b05 xfs: move the di_size field to struct xfs_inode
In preparation of removing the historic icinode struct, move the on-disk
size field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig
ceaf603c70 xfs: move the di_projid field to struct xfs_inode
In preparation of removing the historic icinode struct, move the projid
field into the containing xfs_inode structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig
9b3beb028f xfs: remove the di_dmevmask and di_dmstate fields from struct xfs_icdinode
The legacy DMAPI fields were never set by upstream Linux XFS, and have no
way to be read using the kernel APIs.  So instead of bloating the in-core
inode for them just copy them from the on-disk inode into the log when
logging the inode.  The only caveat is that we need to make sure to zero
the fields for newly read or deleted inodes, which is solved using a new
flag in the inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:03 -07:00
Christoph Hellwig
55f773380e xfs: remove the unused xfs_icdinode_has_bigtime helper
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:02 -07:00
Christoph Hellwig
af9dcddef6 xfs: split xfs_imap_to_bp
Split looking up the dinode from xfs_imap_to_bp, which can be
significantly simplified as a result.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-04-07 14:37:02 -07:00
Chandan Babu R
6e8bd39d72 xfs: Initialize xfs_alloc_arg->total correctly when allocating minlen extents
xfs/538 can cause the following call trace to be printed when executing on a
multi-block directory configuration,

 WARNING: CPU: 1 PID: 2578 at fs/xfs/libxfs/xfs_bmap.c:717 xfs_bmap_extents_to_btree+0x520/0x5d0
 Call Trace:
  ? xfs_buf_rele+0x4f/0x450
  xfs_bmap_add_extent_hole_real+0x747/0x960
  xfs_bmapi_allocate+0x39a/0x440
  xfs_bmapi_write+0x507/0x9e0
  xfs_da_grow_inode_int+0x1cd/0x330
  ? up+0x12/0x60
  xfs_dir2_grow_inode+0x62/0x110
  ? xfs_trans_log_inode+0x234/0x2d0
  xfs_dir2_sf_to_block+0x103/0x940
  ? xfs_dir2_sf_check+0x8c/0x210
  ? xfs_da_compname+0x19/0x30
  ? xfs_dir2_sf_lookup+0xd0/0x3d0
  xfs_dir2_sf_addname+0x10d/0x910
  xfs_dir_createname+0x1ad/0x210
  xfs_create+0x404/0x620
  xfs_generic_create+0x24c/0x320
  path_openat+0xda6/0x1030
  do_filp_open+0x88/0x130
  ? kmem_cache_alloc+0x50/0x210
  ? __cond_resched+0x16/0x40
  ? kmem_cache_alloc+0x50/0x210
  do_sys_openat2+0x97/0x150
  __x64_sys_creat+0x49/0x70
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae

This occurs because xfs_bmap_exact_minlen_extent_alloc() initializes
xfs_alloc_arg->total to xfs_bmalloca->minlen. In the context of
xfs_bmap_exact_minlen_extent_alloc(), xfs_bmalloca->minlen has a value of 1
and hence the space allocator could choose an AG which has less than
xfs_bmalloca->total number of free blocks available. As the transaction
proceeds, one of the future space allocation requests could fail due to
non-availability of free blocks in the AG that was originally chosen.

This commit fixes the bug by assigning xfs_alloc_arg->total to the value of
xfs_bmalloca->total.

Fixes: 3015196746 ("xfs: Introduce error injection to allocate only minlen size extents for files")
Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-04-07 14:36:34 -07:00
Gao Xiang
2b92faed55 xfs: add error injection for per-AG resv failure
per-AG resv failure after fixing up freespace is hard to test in an
effective way, so directly add an error injection path to observe
such error handling path works as expected.

Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-03-25 16:47:53 -07:00
Gao Xiang
46141dc891 xfs: introduce xfs_ag_shrink_space()
This patch introduces a helper to shrink unused space in the last AG
by fixing up the freespace btree.

Also make sure that the per-AG reservation works under the new AG
size. If such per-AG reservation or extent allocation fails, roll
the transaction so the new transaction could cancel without any side
effects.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-03-25 16:47:52 -07:00
Dave Chinner
1fea323ff0 xfs: reduce debug overhead of dir leaf/node checks
On debug kernels, we call xfs_dir3_leaf_check_int() multiple times
on every directory modification. The robust hash ordering checks it
does on every entry in the leaf on every call results in a massive
CPU overhead which slows down debug kernels by a large amount.

We use xfs_dir3_leaf_check_int() for the verifiers as well, so we
can't just gut the function to reduce overhead. What we can do,
however, is reduce the work it does when it is called from the
debug interfaces, just leaving the high level checks in place and
leaving the robust validation to the verifiers. This means the debug
checks will catch gross errors, but subtle bugs might not be caught
until a verifier is run.

It is easy enough to restore the existing debug behaviour if the
developer needs it (just change a call parameter in the debug code),
but overwise the overhead makes testing large directory block sizes
on debug kernels very slow.

Profile at an unlink rate of ~80k file/s on a 64k block size
filesystem before the patch:

  40.30%  [kernel]  [k] xfs_dir3_leaf_check_int
  10.98%  [kernel]  [k] __xfs_dir3_data_check
   8.10%  [kernel]  [k] xfs_verify_dir_ino
   4.42%  [kernel]  [k] memcpy
   2.22%  [kernel]  [k] xfs_dir2_data_get_ftype
   1.52%  [kernel]  [k] do_raw_spin_lock

Profile after, at an unlink rate of ~125k files/s (+50% improvement)
has largely dropped the leaf verification debug overhead out of the
profile.

  16.53%  [kernel]  [k] __xfs_dir3_data_check
  12.53%  [kernel]  [k] xfs_verify_dir_ino
   7.97%  [kernel]  [k] memcpy
   3.36%  [kernel]  [k] xfs_dir2_data_get_ftype
   2.86%  [kernel]  [k] __pv_queued_spin_lock_slowpath

Create shows a similar change in profile and a +25% improvement in
performance.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-03-25 16:47:51 -07:00
Dave Chinner
39d3c0b596 xfs: No need for inode number error injection in __xfs_dir3_data_check
We call xfs_dir_ino_validate() for every dir entry in a directory
when doing validity checking of the directory. It calls
xfs_verify_dir_ino() then emits a corruption report if bad or does
error injection if good. It is extremely costly:

  43.27%  [kernel]  [k] xfs_dir3_leaf_check_int
  10.28%  [kernel]  [k] __xfs_dir3_data_check
   6.61%  [kernel]  [k] xfs_verify_dir_ino
   4.16%  [kernel]  [k] xfs_errortag_test
   4.00%  [kernel]  [k] memcpy
   3.48%  [kernel]  [k] xfs_dir_ino_validate

7% of the cpu usage in this directory traversal workload is
xfs_dir_ino_validate() doing absolutely nothing.

We don't need error injection to simulate a bad inode numbers in the
directory structure because we can do that by fuzzing the structure
on disk.

And we don't need a corruption report, because the
__xfs_dir3_data_check() will emit one if the inode number is bad.

So just call xfs_verify_dir_ino() directly here, and get rid of all
this unnecessary overhead:

  40.30%  [kernel]  [k] xfs_dir3_leaf_check_int
  10.98%  [kernel]  [k] __xfs_dir3_data_check
   8.10%  [kernel]  [k] xfs_verify_dir_ino
   4.42%  [kernel]  [k] memcpy
   2.22%  [kernel]  [k] xfs_dir2_data_get_ftype
   1.52%  [kernel]  [k] do_raw_spin_lock

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-03-25 16:47:51 -07:00
Dave Chinner
ec08c14ba2 xfs: type verification is expensive
From a concurrent rm -rf workload:

  41.04%  [kernel]  [k] xfs_dir3_leaf_check_int
   9.85%  [kernel]  [k] __xfs_dir3_data_check
   5.60%  [kernel]  [k] xfs_verify_ino
   5.32%  [kernel]  [k] xfs_agino_range
   4.21%  [kernel]  [k] memcpy
   3.06%  [kernel]  [k] xfs_errortag_test
   2.57%  [kernel]  [k] xfs_dir_ino_validate
   1.66%  [kernel]  [k] xfs_dir2_data_get_ftype
   1.17%  [kernel]  [k] do_raw_spin_lock
   1.11%  [kernel]  [k] xfs_verify_dir_ino
   0.84%  [kernel]  [k] __raw_callee_save___pv_queued_spin_unlock
   0.83%  [kernel]  [k] xfs_buf_find
   0.64%  [kernel]  [k] xfs_log_commit_cil

THere's an awful lot of overhead in just range checking inode
numbers in that, but each inode number check is not a lot of code.
The total is a bit over 14.5% of the CPU time is spent validating
inode numbers.

The problem is that they deeply nested global scope functions so the
overhead here is all in function call marshalling.

   text	   data	    bss	    dec	    hex	filename
   2077	      0	      0	   2077	    81d fs/xfs/libxfs/xfs_types.o.orig
   2197	      0	      0	   2197	    895	fs/xfs/libxfs/xfs_types.o

There's a small increase in binary size by inlining all the local
nested calls in the verifier functions, but the same workload now
profiles as:

  40.69%  [kernel]  [k] xfs_dir3_leaf_check_int
  10.52%  [kernel]  [k] __xfs_dir3_data_check
   6.68%  [kernel]  [k] xfs_verify_dir_ino
   4.22%  [kernel]  [k] xfs_errortag_test
   4.15%  [kernel]  [k] memcpy
   3.53%  [kernel]  [k] xfs_dir_ino_validate
   1.87%  [kernel]  [k] xfs_dir2_data_get_ftype
   1.37%  [kernel]  [k] do_raw_spin_lock
   0.98%  [kernel]  [k] xfs_buf_find
   0.94%  [kernel]  [k] __raw_callee_save___pv_queued_spin_unlock
   0.73%  [kernel]  [k] xfs_log_commit_cil

Now we only spend just over 10% of the time validing inode numbers
for the same workload. Hence a few "inline" keyworks is good enough
to reduce the validation overhead by 30%...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-03-25 16:47:51 -07:00
Dave Chinner
e6a688c332 xfs: initialise attr fork on inode create
When we allocate a new inode, we often need to add an attribute to
the inode as part of the create. This can happen as a result of
needing to add default ACLs or security labels before the inode is
made visible to userspace.

This is highly inefficient right now. We do the create transaction
to allocate the inode, then we do an "add attr fork" transaction to
modify the just created empty inode to set the inode fork offset to
allow attributes to be stored, then we go and do the attribute
creation.

This means 3 transactions instead of 1 to allocate an inode, and
this greatly increases the load on the CIL commit code, resulting in
excessive contention on the CIL spin locks and performance
degradation:

 18.99%  [kernel]                [k] __pv_queued_spin_lock_slowpath
  3.57%  [kernel]                [k] do_raw_spin_lock
  2.51%  [kernel]                [k] __raw_callee_save___pv_queued_spin_unlock
  2.48%  [kernel]                [k] memcpy
  2.34%  [kernel]                [k] xfs_log_commit_cil

The typical profile resulting from running fsmark on a selinux enabled
filesytem is adds this overhead to the create path:

  - 15.30% xfs_init_security
     - 15.23% security_inode_init_security
	- 13.05% xfs_initxattrs
	   - 12.94% xfs_attr_set
	      - 6.75% xfs_bmap_add_attrfork
		 - 5.51% xfs_trans_commit
		    - 5.48% __xfs_trans_commit
		       - 5.35% xfs_log_commit_cil
			  - 3.86% _raw_spin_lock
			     - do_raw_spin_lock
				  __pv_queued_spin_lock_slowpath
		 - 0.70% xfs_trans_alloc
		      0.52% xfs_trans_reserve
	      - 5.41% xfs_attr_set_args
		 - 5.39% xfs_attr_set_shortform.constprop.0
		    - 4.46% xfs_trans_commit
		       - 4.46% __xfs_trans_commit
			  - 4.33% xfs_log_commit_cil
			     - 2.74% _raw_spin_lock
				- do_raw_spin_lock
				     __pv_queued_spin_lock_slowpath
			       0.60% xfs_inode_item_format
		      0.90% xfs_attr_try_sf_addname
	- 1.99% selinux_inode_init_security
	   - 1.02% security_sid_to_context_force
	      - 1.00% security_sid_to_context_core
		 - 0.92% sidtab_entry_to_string
		    - 0.90% sidtab_sid2str_get
			 0.59% sidtab_sid2str_put.part.0
	   - 0.82% selinux_determine_inode_label
	      - 0.77% security_transition_sid
		   0.70% security_compute_sid.part.0

And fsmark creation rate performance drops by ~25%. The key point to
note here is that half the additional overhead comes from adding the
attribute fork to the newly created inode. That's crazy, considering
we can do this same thing at inode create time with a couple of
lines of code and no extra overhead.

So, if we know we are going to add an attribute immediately after
creating the inode, let's just initialise the attribute fork inside
the create transaction and chop that whole chunk of code out of
the create fast path. This completely removes the performance
drop caused by enabling SELinux, and the profile looks like:

     - 8.99% xfs_init_security
         - 9.00% security_inode_init_security
            - 6.43% xfs_initxattrs
               - 6.37% xfs_attr_set
                  - 5.45% xfs_attr_set_args
                     - 5.42% xfs_attr_set_shortform.constprop.0
                        - 4.51% xfs_trans_commit
                           - 4.54% __xfs_trans_commit
                              - 4.59% xfs_log_commit_cil
                                 - 2.67% _raw_spin_lock
                                    - 3.28% do_raw_spin_lock
                                         3.08% __pv_queued_spin_lock_slowpath
                                   0.66% xfs_inode_item_format
                        - 0.90% xfs_attr_try_sf_addname
                  - 0.60% xfs_trans_alloc
            - 2.35% selinux_inode_init_security
               - 1.25% security_sid_to_context_force
                  - 1.21% security_sid_to_context_core
                     - 1.19% sidtab_entry_to_string
                        - 1.20% sidtab_sid2str_get
                           - 0.86% sidtab_sid2str_put.part.0
                              - 0.62% _raw_spin_lock_irqsave
                                 - 0.77% do_raw_spin_lock
                                      __pv_queued_spin_lock_slowpath
               - 0.84% selinux_determine_inode_label
                  - 0.83% security_transition_sid
                       0.86% security_compute_sid.part.0

Which indicates the XFS overhead of creating the selinux xattr has
been halved. This doesn't fix the CIL lock contention problem, just
means it's not a limiting factor for this workload. Lock contention
in the security subsystems is going to be an issue soon, though...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[djwong: fix compilation error when CONFIG_SECURITY=n]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
2021-03-25 16:47:51 -07:00
Darrick J. Wong
383e32b0d0 xfs: prevent metadata files from being inactivated
Files containing metadata (quota records, rt bitmap and summary info)
are fully managed by the filesystem, which means that all resource
cleanup must be explicit, not automatic.  This means that they should
never be subjected automatic to post-eof truncation, nor should they be
freed automatically even if the link count drops to zero.

In other words, xfs_inactive() should leave these files alone.  Add the
necessary predicate functions to make this happen.  This adds a second
layer of prevention for the kinds of fs corruption that was fixed by
commit f4c32e87de.  If we ever decide to support removing metadata
files, we should make all those metadata updates explicit.

Rearrange the order of #includes to fix compiler errors, since
xfs_mount.h is supposed to be included before xfs_inode.h

Followup-to: f4c32e87de ("xfs: fix realtime bitmap/summary file truncation when growing rt volume")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-03-25 16:47:50 -07:00
Darrick J. Wong
973975b72a xfs: validate ag btree levels using the precomputed values
Use the AG btree height limits that we precomputed into the xfs_mount to
validate the AG headers instead of using XFS_BTREE_MAXLEVELS.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-03-25 16:47:50 -07:00