There is a race condition that can trigger in dmflakey fstests that
can result in asserts in xfs_ialloc_read_agi() and
xfs_alloc_read_agf() firing. The asserts look like this:
XFS: Assertion failed: pag->pagf_freeblks == be32_to_cpu(agf->agf_freeblks), file: fs/xfs/libxfs/xfs_alloc.c, line: 3440
.....
Call Trace:
<TASK>
xfs_alloc_read_agf+0x2ad/0x3a0
xfs_alloc_fix_freelist+0x280/0x720
xfs_alloc_vextent_prepare_ag+0x42/0x120
xfs_alloc_vextent_iterate_ags+0x67/0x260
xfs_alloc_vextent_start_ag+0xe4/0x1c0
xfs_bmapi_allocate+0x6fe/0xc90
xfs_bmapi_convert_delalloc+0x338/0x560
xfs_map_blocks+0x354/0x580
iomap_writepages+0x52b/0xa70
xfs_vm_writepages+0xd7/0x100
do_writepages+0xe1/0x2c0
__writeback_single_inode+0x44/0x340
writeback_sb_inodes+0x2d0/0x570
__writeback_inodes_wb+0x9c/0xf0
wb_writeback+0x139/0x2d0
wb_workfn+0x23e/0x4c0
process_scheduled_works+0x1d4/0x400
worker_thread+0x234/0x2e0
kthread+0x147/0x170
ret_from_fork+0x3e/0x50
ret_from_fork_asm+0x1a/0x30
I've seen the AGI variant from scrub running on the filesysetm
after unmount failed due to systemd interference:
XFS: Assertion failed: pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) || xfs_is_shutdown(pag->pag_mount), file: fs/xfs/libxfs/xfs_ialloc.c, line: 2804
.....
Call Trace:
<TASK>
xfs_ialloc_read_agi+0xee/0x150
xchk_perag_drain_and_lock+0x7d/0x240
xchk_ag_init+0x34/0x90
xchk_inode_xref+0x7b/0x220
xchk_inode+0x14d/0x180
xfs_scrub_metadata+0x2e2/0x510
xfs_ioc_scrub_metadata+0x62/0xb0
xfs_file_ioctl+0x446/0xbf0
__se_sys_ioctl+0x6f/0xc0
__x64_sys_ioctl+0x1d/0x30
x64_sys_call+0x1879/0x2ee0
do_syscall_64+0x68/0x130
? exc_page_fault+0x62/0xc0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Essentially, it is the same problem. When _flakey_drop_and_remount()
loads the drop-writes table, it makes all writes silently fail. Writes
are reported to the fs as completed successfully, but they are not
issued to the backing store. The filesystem sees the successful
write completion and marks the metadata buffer clean and removes it
from the AIL.
If this happens at the same time as memory pressure is occuring,
the now-clean AGF and/or AGI buffers can be reclaimed from memory.
Shortly afterwards, but before _flakey_drop_and_remount() runs
unmount, background writeback is kicked and it tries to allocate
blocks for the dirty pages in memory. This then tries to access the
AGF buffer we just turfed out of memory. It's not found, so it gets
read in from disk.
This is all fine, except for the fact that the last writeback of the
AGF did not actually reach disk. The AGF on disk is stale compared
to the in-memory state held by the perag, and so they don't match
and the assert fires.
Then other operations on that inode hang because the task was killed
whilst holding inode locks. e.g:
Workqueue: xfs-conv/dm-12 xfs_end_io
Call Trace:
<TASK>
__schedule+0x650/0xb10
schedule+0x6d/0xf0
schedule_preempt_disabled+0x15/0x30
rwsem_down_write_slowpath+0x31a/0x5f0
down_write+0x43/0x60
xfs_ilock+0x1a8/0x210
xfs_trans_alloc_inode+0x9c/0x240
xfs_iomap_write_unwritten+0xe3/0x300
xfs_end_ioend+0x90/0x130
xfs_end_io+0xce/0x100
process_scheduled_works+0x1d4/0x400
worker_thread+0x234/0x2e0
kthread+0x147/0x170
ret_from_fork+0x3e/0x50
ret_from_fork_asm+0x1a/0x30
</TASK>
and it's all down hill from there.
Memory pressure is one way to trigger this, another is to run "echo
3 > /proc/sys/vm/drop_caches" randomly while tests are running.
Regardless of how it is triggered, this effectively takes down the
system once umount hangs because it's holding a sb->s_umount lock
exclusive and now every sync(1) call gets stuck on it.
Fix this by replacing the asserts with a corruption detection check
and a shutdown.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Unmapped buffer access is a pain, so kill it. The switch to large
folios means we rarely pay a vmap penalty for large buffers,
so this functionality is largely unnecessary now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
xfs_{add,dec}_freecounter already handles the block and RT extent
percpu counters, but it currently hardcodes the passed in counter.
Add a freecounter abstraction that uses an enum to designate the counter
and add wrappers that hide the actual percpu_counters. This will allow
expanding the reserved block handling to the RT extent counter in the
next step, and also prepares for adding yet another such counter that
can share the code. Both these additions will be needed for the zoned
allocator.
Also switch the flooring of the frextents counter to 0 in statfs for the
rthinherit case to a manual min_t call to match the handling of the
fdblocks counter for normal file systems.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
The runt AG at the end of a filesystem is almost always smaller than
the mp->m_sb.sb_agblocks. Unfortunately, when setting the max_agbno
limit for the inode chunk allocation, we do not take this into
account. This means we can allocate a sparse inode chunk that
overlaps beyond the end of an AG. When we go to allocate an inode
from that sparse chunk, the irec fails validation because the
agbno of the start of the irec is beyond valid limits for the runt
AG.
Prevent this from happening by taking into account the size of the
runt AG when allocating inode chunks. Also convert the various
checks for valid inode chunk agbnos to use xfs_ag_block_count()
so that they will also catch such issues in the future.
Fixes: 56d1115c9b ("xfs: allocate sparse inode chunks on full chunk allocation failure")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Ideally, we'd put all the metadata inodes in one place if we could, so
that the metadata all stay reasonably close together instead of
spreading out over the disk. Furthermore, if the log is internal we'd
probably prefer to keep the metadata near the log. Therefore, disable
AGI rotoring for metadata inode allocations.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Replace the pag pointers in the type specific union with a generic
xfs_group pointer. This prepares for adding realtime group support.
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>
Split the lookup and refcount handling of struct xfs_perag into an
embedded xfs_group structure that can be reused for the upcoming
realtime groups.
It will be extended with more features later.
Note that he xg_type field will only need a single bit even with
realtime group support. For now it fills a hole, but it might be
worth to fold it into another field if we can use this space better.
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>
Convert all tracepoints that take [mp,agno] tuples to take a pag argument
instead so that decoding only happens when tracepoints are enabled and to
clean up the callers.
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>
Pass the perag structure and the irec to these tracepoints so that the
decoding is only done when tracing is actually enabled and the call sites
look a lot neater.
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>
Add a helpers to convert an agino to an ino based on a pag structure.
This provides a simpler conversion and better type safety compared to the
existing code that passes the mount structure and the agno separately.
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>
Add helpers to convert an agbno to a daddr or fsbno based on a pag
structure.
This provides a simpler conversion and better type safety compared to the
existing code that passes the mount structure and the agno separately.
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>
We'll want to use more than just the agno field in a bit.
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>
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Merge tag 'vfs-6.12.blocksize' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull vfs blocksize updates from Christian Brauner:
"This contains the vfs infrastructure as well as the xfs bits to enable
support for block sizes (bs) larger than page sizes (ps) plus a few
fixes to related infrastructure.
There has been efforts over the last 16 years to enable enable Large
Block Sizes (LBS), that is block sizes in filesystems where bs > page
size. Through these efforts we have learned that one of the main
blockers to supporting bs > ps in filesystems has been a way to
allocate pages that are at least the filesystem block size on the page
cache where bs > ps.
Thanks to various previous efforts it is possible to support bs > ps
in XFS with only a few changes in XFS itself. Most changes are to the
page cache to support minimum order folio support for the target block
size on the filesystem.
A motivation for Large Block Sizes today is to support high-capacity
(large amount of Terabytes) QLC SSDs where the internal Indirection
Unit (IU) are typically greater than 4k to help reduce DRAM and so in
turn cost and space. In practice this then allows different
architectures to use a base page size of 4k while still enabling
support for block sizes aligned to the larger IUs by relying on high
order folios on the page cache when needed.
It also allows to take advantage of the drive's support for atomics
larger than 4k with buffered IO support in Linux. As described this
year at LSFMM, supporting large atomics greater than 4k enables
databases to remove the need to rely on their own journaling, so they
can disable double buffered writes, which is a feature different cloud
providers are already enabling through custom storage solutions"
* tag 'vfs-6.12.blocksize' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (22 commits)
Documentation: iomap: fix a typo
iomap: remove the iomap_file_buffered_write_punch_delalloc return value
iomap: pass the iomap to the punch callback
iomap: pass flags to iomap_file_buffered_write_punch_delalloc
iomap: improve shared block detection in iomap_unshare_iter
iomap: handle a post-direct I/O invalidate race in iomap_write_delalloc_release
docs:filesystems: fix spelling and grammar mistakes in iomap design page
filemap: fix htmldoc warning for mapping_align_index()
iomap: make zero range flush conditional on unwritten mappings
iomap: fix handling of dirty folios over unwritten extents
iomap: add a private argument for iomap_file_buffered_write
iomap: remove set_memor_ro() on zero page
xfs: enable block size larger than page size support
xfs: make the calculation generic in xfs_sb_validate_fsb_count()
xfs: expose block size in stat
xfs: use kvmalloc for xattr buffers
iomap: fix iomap_dio_zero() for fs bs > system page size
filemap: cap PTE range to be created to allowed zero fill in folio_map_range()
mm: split a folio in minimum folio order chunks
readahead: allocate folios with mapping_min_order in readahead
...
Standardize the parameters in xfs_{alloc,bm,ino,rmap,refcount}bt_maxrecs
so that we have consistent calling conventions. This doesn't affect the
kernel that much, but enables us to clean up userspace a bit.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Pass the xfs_icreate_args object to xfs_dialloc since we can extract the
relevant mode (really just the file type) and parent inumber from there.
This simplifies the calling convention in preparation for the next
patch.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Convert the boolean to skip discard on free into a proper flags field so
that we can add more flags in the next patch.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
There are two parts to initializing a newly allocated inode: setting up
the incore structures, and initializing the new inode core based on the
parent inode and the current user's environment. The initialization
code is not specific to the kernel, so we would like to share that with
userspace by hoisting it to libxfs. Therefore, split xfs_icreate into
separate functions to prepare for the next few patches.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
I noticed that xfs/413 and xfs/375 occasionally failed while fuzzing
core.mode of an inode. The root cause of these problems is that the
field we fuzzed (core.mode or core.magic, typically) causes the entire
inode cluster buffer verification to fail, which affects several inodes
at once. The repair process tries to create either a /lost+found or a
temporary repair file, but regrettably it picks the same inode cluster
that we just corrupted, with the result that repair triggers the demise
of the filesystem.
Try avoid this by making the inode allocation path detect when the perag
health status indicates that someone has found bad inode cluster
buffers, and try to read the inode cluster buffer. If the cluster
buffer fails the verifiers, try another AG. This isn't foolproof and
can result in premature ENOSPC, but that might be better than shutting
down.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Allow callers to pass buffer lookup flags to xfs_read_agi and
xfs_ialloc_read_agi. This will be used in the next patch to fix a
deadlock in the online fsck inode scanner.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The last checks for bc_btnum can be replaced with helpers that check
the btree ops. This allows adding new btrees to XFS without having
to update a global enum.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: complete the ops predicates]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
This is one of the last users of xfs_btnum_t and can only designate
either the inobt or finobt. Replace it with a simple bool.
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>
Split xfs_inobt_init_cursor into separate routines for the inobt and
finobt to prepare for the removal of the xfs_btnum global enumeration
of btree types.
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>
Split the finobt version that never merges and uses a different cursor
out of xfs_inobt_insert_sprec to prepare for removing xfs_btnum_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>
The btnum in struct xfs_btree_ops is often used for printing a symbolic
name for the btree. Add a name field to the ops structure and use that
directly.
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>
Whenever we encounter XFS_IS_CORRUPT failures, we should report that to
the health monitoring system for later reporting.
I started with this semantic patch and massaged everything until it
built:
@@
expression mp, test;
@@
- if (XFS_IS_CORRUPT(mp, test)) return -EFSCORRUPTED;
+ if (XFS_IS_CORRUPT(mp, test)) { xfs_btree_mark_sick(cur); return -EFSCORRUPTED; }
@@
expression mp, test;
identifier label, error;
@@
- if (XFS_IS_CORRUPT(mp, test)) { error = -EFSCORRUPTED; goto label; }
+ if (XFS_IS_CORRUPT(mp, test)) { xfs_btree_mark_sick(cur); error = -EFSCORRUPTED; goto label; }
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Whenever we encounter corrupt inode records, we should report that to
the health monitoring system for later reporting.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Whenever we encounter corrupt btree blocks, we should report that to the
health monitoring system for later reporting.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Whenever we encounter a corrupt AG header, we should report that to the
health monitoring system for later reporting. Buffer readers that don't
respond to corruption events with a _mark_sick call can be detected with
the following script:
#!/bin/bash
# Detect missing calls to xfs_*_mark_sick
filter=cat
tty -s && filter=less
git grep -A10 -E '( = xfs_trans_read_buf| = xfs_buf_read\()' fs/xfs/*.[ch] fs/xfs/libxfs/*.[ch] | awk '
BEGIN {
ignore = 0;
lineno = 0;
delete lines;
}
{
if ($0 == "--") {
if (!ignore) {
for (i = 0; i < lineno; i++) {
print(lines[i]);
}
printf("--\n");
}
delete lines;
lineno = 0;
ignore = 0;
} else if ($0 ~ /mark_sick/) {
ignore = 1;
} else {
lines[lineno++] = $0;
}
}
' | $filter
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Use the rmapbt to find inode chunks, query the chunks to compute hole
and free masks, and with that information rebuild the inobt and finobt.
Refer to the case study in
Documentation/filesystems/xfs-online-fsck-design.rst for more details.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
xfs_free_extent_later is a trivial helper, so remove it to reduce the
amount of thinking required to understand the deferred freeing
interface. This will make it easier to introduce automatic reaping of
speculative allocations in the next patch.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Similar to the recent patch strengthening the AGF agf_length
verification, the AGI verifier does not check that the AGI length field
is within known good bounds. This isn't currently checked by runtime
kernel code, yet we assume in many places that it is correct and verify
other metadata against it.
Add length verification to the AGI verifier. Just like the AGF length
checking, the length of the AGI must be equal to the size of the AG
specified in the superblock, unless it is the last AG in the filesystem.
In that case, it must be less than or equal to sb->sb_agblocks and
greater than XFS_MIN_AG_BLOCKS, which is the smallest AG a growfs
operation will allow to exist.
There's only one place in the filesystem that actually uses agi_length,
but let's not leave it vulnerable to the same weird nonsense that
generates syzbot bugs, eh?
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Btrees that aren't freespace management trees use the normal extent
allocation and freeing routines for their blocks. Hence when a btree
block is freed, a direct call to xfs_free_extent() is made and the
extent is immediately freed. This puts the entire free space
management btrees under this path, so we are stacking btrees on
btrees in the call stack. The inobt, finobt and refcount btrees
all do this.
However, the bmap btree does not do this - it calls
xfs_free_extent_later() to defer the extent free operation via an
XEFI and hence it gets processed in deferred operation processing
during the commit of the primary transaction (i.e. via intent
chaining).
We need to change xfs_free_extent() to behave in a non-blocking
manner so that we can avoid deadlocks with busy extents near ENOSPC
in transactions that free multiple extents. Inserting or removing a
record from a btree can cause a multi-level tree merge operation and
that will free multiple blocks from the btree in a single
transaction. i.e. we can call xfs_free_extent() multiple times, and
hence the btree manipulation transaction is vulnerable to this busy
extent deadlock vector.
To fix this, convert all the remaining callers of xfs_free_extent()
to use xfs_free_extent_later() to queue XEFIs and hence defer
processing of the extent frees to a context that can be safely
restarted if a deadlock condition is detected.
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>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Bad things happen in defered extent freeing operations if it is
passed a bad block number in the xefi. This can come from a bogus
agno/agbno pair from deferred agfl freeing, or just a bad fsbno
being passed to __xfs_free_extent_later(). Either way, it's very
difficult to diagnose where a null perag oops in EFI creation
is coming from when the operation that queued the xefi has already
been completed and there's no longer any trace of it around....
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Convert the xfs_ialloc_has_inodes_at_extent function to return keyfill
scan results because for a given range of inode numbers, we might have
no indexed inodes at all; the entire region might be allocated ondisk
inodes; or there might be a mix of the two.
Unfortunately, sparse inodes adds to the complexity, because each inode
record can have holes, which means that we cannot use the generic btree
_scan_keyfill function because we must look for holes in individual
records to decide the result. On the plus side, online fsck can now
detect sub-chunk discrepancies in the inobt.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
In xfs_difree_inobt, the pag passed in was previously used to look up
the AGI buffer. There's no need to extract it again, so remove the
shadow variable and shut up -Wshadow.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Move the inobt record alignment checks from xchk_iallocbt_rec into
xfs_inobt_check_irec so that they are applied everywhere.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
For every btree type except for the bmbt, refactor the code that
complains about bad records into a helper and make the ->query_range
helpers call it so that corruptions found via that avenue are logged.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Create a xfs_inobt_check_irec function to detect corruption in btree
records. Fix all xfs_inobt_btrec_to_irec callsites to call the new
helper and bubble up corruption reports.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Prior to the removal of xfs_ialloc_next_ag, we would increment the agi
rotor and return the *old* value. atomic_inc_return returns the new
value, which causes mkfs to allocate the root directory in AG 1. Put
back the old behavior (at least for mkfs) by subtracting 1 here.
Fixes: 20a5eab49d ("xfs: convert xfs_ialloc_next_ag() to an atomic")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Two of the callers to xfs_alloc_vextent_this_ag() actually want
exact block number allocation, not anywhere-in-ag allocation. Split
this out from _this_ag() as a first class citizen so no external
extent allocation code needs to care about args->type anymore.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
The remaining callers of xfs_alloc_vextent() are all doing NEAR_BNO
allocations. We can replace that function with a new
xfs_alloc_vextent_near_bno() function that does this explicitly.
We also multiplex NEAR_BNO allocations through
xfs_alloc_vextent_this_ag via args->type. Replace all of these with
direct calls to xfs_alloc_vextent_near_bno(), too.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Change obvious callers of single AG allocation to use
xfs_alloc_vextent_this_ag(). Drive the per-ag grabbing out to the
callers, too, so that callers with active references don't need
to do new lookups just for an allocation in a context that already
has a perag reference.
The only remaining caller that does single AG allocation through
xfs_alloc_vextent() is xfs_bmap_btalloc() with
XFS_ALLOCTYPE_NEAR_BNO. That is going to need more untangling before
it can be converted cleanly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
In several places we iterate every AG from a specific start agno and
wrap back to the first AG when we reach the end of the filesystem to
continue searching. We don't have a primitive for this iteration
yet, so add one for conversion of these algorithms to per-ag based
iteration.
The filestream AG select code is a mess, and this initially makes it
worse. The per-ag selection needs to be driven completely into the
filestream code to clean this up and it will be done in a future
patch that makes the filestream allocator use active per-ag
references correctly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
We currently don't have any flags or operational state in the
xfs_perag except for the pagf_init and pagi_init flags. And the
agflreset flag. Oh, there's also the pagf_metadata and pagi_inodeok
flags, too.
For controlling per-ag operations, we are going to need some atomic
state flags. Hence add an opstate field similar to what we already
have in the mount and log, and convert all these state flags across
to atomic bit operations.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
This is currently a spinlock lock protected rotor which can be
implemented with a single atomic operation. Change it to be more
efficient and get rid of the m_agirotor_lock. Noticed while
converting the inode allocation AG selection loop to active perag
references.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Lots of code in the inobt infrastructure is passed both xfs_mount
and perags. We only need perags for the per-ag inode allocation
code, so reduce the duplication by passing only the perags as the
primary object.
This ends up reducing the code size by a bit:
text data bss dec hex filename
orig 1138878 323979 548 1463405 16546d (TOTALS)
patched 1138709 323979 548 1463236 1653c4 (TOTALS)
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Convert the inode allocation routines to use active perag references
or references held by callers rather than grab their own. Also drive
the perag further inwards to replace xfs_mounts when doing
operations on a specific AG.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Callers have referenced perags but they don't pass it into
xfs_imap() so it takes it's own reference. Fix that so we can change
inode allocation over to using active references.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
When an XFS filesystem has free inodes in chunks already allocated
on disk, it will still allocate new inode chunks if the target AG
has no free inodes in it. Normally, this is a good idea as it
preserves locality of all the inodes in a given directory.
However, at ENOSPC this can lead to using the last few remaining
free filesystem blocks to allocate a new chunk when there are many,
many free inodes that could be allocated without consuming free
space. This results in speeding up the consumption of the last few
blocks and inode create operations then returning ENOSPC when there
free inodes available because we don't have enough block left in the
filesystem for directory creation reservations to proceed.
Hence when we are near ENOSPC, we should be attempting to preserve
the remaining blocks for directory block allocation rather than
using them for unnecessary inode chunk creation.
This particular behaviour is exposed by xfs/294, when it drives to
ENOSPC on empty file creation whilst there are still thousands of
free inodes available for allocation in other AGs in the filesystem.
Hence, when we are within 1% of ENOSPC, change the inode allocation
behaviour to prefer to use existing free inodes over allocating new
inode chunks, even though it results is poorer locality of the data
set. It is more important for the allocations to be space efficient
near ENOSPC than to have optimal locality for performance, so lets
modify the inode AG selection code to reflect that fact.
This allows generic/294 to not only pass with this allocator rework
patchset, but to increase the number of post-ENOSPC empty inode
allocations to from ~600 to ~9080 before we hit ENOSPC on the
directory create transaction reservation.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
