Searched +hist:6 +hist:e73a545 (Results 1 - 16 of 16) sorted by path

/linux-master/fs/xfs/libxfs/
H A Dxfs_bmap.cdiff 6c8127e9 Thu Feb 22 01:45:00 MST 2024 Darrick J. Wong <djwong@kernel.org> xfs: xfs_bmap_finish_one should map unwritten extents properly

The deferred bmap work state and the log item can transmit unwritten
state, so the XFS_BMAP_MAP handler must map in extents with that
unwritten state.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 6a701eb8 Thu Feb 22 01:41:01 MST 2024 Christoph Hellwig <hch@lst.de> xfs: move and rename xfs_btree_read_bufl

Despite its name, xfs_btree_read_bufl doesn't contain any btree-related
functionaliy and isn't used by the btree code. Move it to xfs_bmap.c,
hard code the refval and ops arguments and rename it to
xfs_bmap_read_buf.

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>
diff 6e145f94 Tue Dec 19 23:34:55 MST 2023 Christoph Hellwig <hch@lst.de> xfs: make if_data a void pointer

The xfs_ifork structure currently has a union of the if_root void pointer
and the if_data char pointer. In either case it is an opaque pointer
that depends on the fork format. Replace the union with a single if_data
void pointer as that is what almost all callers want. Only the symlink
NULL termination code in xfs_init_local_fork actually needs a new local
variable now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 6c664484 Mon Oct 16 10:16:22 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: hoist freeing of rt data fork extent mappings

Currently, xfs_bmap_del_extent_real contains a bunch of code to convert
the physical extent of a data fork mapping for a realtime file into rt
extents and pass that to the rt extent freeing function. Since the
details of this aren't needed when CONFIG_XFS_REALTIME=n, move it to
xfs_rtbitmap.c to reduce code size when realtime isn't enabled.

This will (one day) enable realtime EFIs to reuse the same
unit-converting call with less code duplication.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff b82a5c42 Mon May 01 17:14:27 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: don't unconditionally null args->pag in xfs_bmap_btalloc_at_eof

xfs/170 on a filesystem with su=128k,sw=4 produces this splat:

BUG: kernel NULL pointer dereference, address: 0000000000000010
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP
CPU: 1 PID: 4022907 Comm: dd Tainted: G W 6.3.0-xfsx #2 6ebeeffbe9577d32
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20171121_152543-x86-ol7-bu
RIP: 0010:xfs_perag_rele+0x10/0x70 [xfs]
RSP: 0018:ffffc90001e43858 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000100
RDX: ffffffffa054e717 RSI: 0000000000000005 RDI: 0000000000000000
RBP: ffff888194eea000 R08: 0000000000000000 R09: 0000000000000037
R10: ffff888100ac1cb0 R11: 0000000000000018 R12: 0000000000000000
R13: ffffc90001e43a38 R14: ffff888194eea000 R15: ffff888194eea000
FS: 00007f93d1a0e740(0000) GS:ffff88843fc80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 000000018a34f000 CR4: 00000000003506e0
Call Trace:
<TASK>
xfs_bmap_btalloc+0x1a7/0x5d0 [xfs f85291d6841cbb3dc740083f1f331c0327394518]
xfs_bmapi_allocate+0xee/0x470 [xfs f85291d6841cbb3dc740083f1f331c0327394518]
xfs_bmapi_write+0x539/0x9e0 [xfs f85291d6841cbb3dc740083f1f331c0327394518]
xfs_iomap_write_direct+0x1bb/0x2b0 [xfs f85291d6841cbb3dc740083f1f331c0327394518]
xfs_direct_write_iomap_begin+0x51c/0x710 [xfs f85291d6841cbb3dc740083f1f331c0327394518]
iomap_iter+0x132/0x2f0
__iomap_dio_rw+0x2f8/0x840
iomap_dio_rw+0xe/0x30
xfs_file_dio_write_aligned+0xad/0x180 [xfs f85291d6841cbb3dc740083f1f331c0327394518]
xfs_file_write_iter+0xfb/0x190 [xfs f85291d6841cbb3dc740083f1f331c0327394518]
vfs_write+0x2eb/0x410
ksys_write+0x65/0xe0
do_syscall_64+0x2b/0x80

This crash occurs under the "out_low_space" label. We grabbed a perag
reference, passed it via args->pag into xfs_bmap_btalloc_at_eof, and
afterwards args->pag is NULL. Fix the second function not to clobber
args->pag if the caller had passed one in.

Fixes: 85843327094f ("xfs: factor xfs_bmap_btalloc()")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6a3bd8fc Tue Apr 11 20:00:05 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: complain about bad file mapping records in the ondisk bmbt

Similar to what we've just done for the other btrees, create a function
to log corrupt bmbt records and call it whenever we encounter a bad
record in the ondisk btree.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 6b637ad0 Sun Feb 12 15:14:55 MST 2023 Dave Chinner <dchinner@redhat.com> xfs: get rid of notinit from xfs_bmap_longest_free_extent

It is only set if reading the AGF gets a EAGAIN error. Just return
the EAGAIN error and handle that error in the callers.

This means we can remove the not_init parameter from
xfs_bmap_select_minlen(), too, because the use of not_init there is
pessimistic. If we can't read the agf, it won't increase blen.

The only time we actually care whether we checked all the AGFs for
contiguous free space is when the best length is less than the
minimum allocation length. If not_init is set, then we ignore blen
and set the minimum alloc length to the absolute minimum, not the
best length we know already is present.

However, if blen is less than the minimum we're going to ignore it
anyway, regardless of whether we scanned all the AGFs or not. Hence
not_init can go away, because we only use if blen is good from
the scanned AGs otherwise we ignore it altogether and use minlen.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
diff 6ca444cf Thu Sep 16 01:24:04 MDT 2021 Darrick J. Wong <djwong@kernel.org> xfs: prepare xfs_btree_cur for dynamic cursor heights

Split out the btree level information into a separate struct and put it
at the end of the cursor structure as a VLA. Files with huge data forks
(and in the future, the realtime rmap btree) will require the ability to
support many more levels than a per-AG btree cursor, which means that
we're going to create per-btree type cursor caches to conserve memory
for the more common case.

Note that a subsequent patch actually introduces dynamic cursor heights.
This one merely rearranges the structure to prepare for that.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
H A Dxfs_bmap_btree.cdiff 6abc7aef Tue Apr 11 20:00:10 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: replace xfs_btree_has_record with a general keyspace scanner

The current implementation of xfs_btree_has_record returns true if it
finds /any/ record within the given range. Unfortunately, that's not
sufficient for scrub. We want to be able to tell if a range of keyspace
for a btree is devoid of records, is totally mapped to records, or is
somewhere in between. By forcing this to be a boolean, we conflated
sparseness and fullness, which caused scrub to return incorrect results.
Fix the API so that we can tell the caller which of those three is the
current state.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6bdcf26a Fri Nov 03 11:34:46 MDT 2017 Christoph Hellwig <hch@lst.de> 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>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
H A Dxfs_da_btree.cdiff 5759aa4f Mon Dec 04 22:58:59 MST 2023 Zhang Tianci <zhangtianci.1997@bytedance.com> xfs: update dir3 leaf block metadata after swap

xfs_da3_swap_lastblock() copy the last block content to the dead block,
but do not update the metadata in it. We need update some metadata
for some kinds of type block, such as dir3 leafn block records its
blkno, we shall update it to the dead block blkno. Otherwise,
before write the xfs_buf to disk, the verify_write() will fail in
blk_hdr->blkno != xfs_buf->b_bn, then xfs will be shutdown.

We will get this warning:

XFS (dm-0): Metadata corruption detected at xfs_dir3_leaf_verify+0xa8/0xe0 [xfs], xfs_dir3_leafn block 0x178
XFS (dm-0): Unmount and run xfs_repair
XFS (dm-0): First 128 bytes of corrupted metadata buffer:
00000000e80f1917: 00 80 00 0b 00 80 00 07 3d ff 00 00 00 00 00 00 ........=.......
000000009604c005: 00 00 00 00 00 00 01 a0 00 00 00 00 00 00 00 00 ................
000000006b6fb2bf: e4 44 e3 97 b5 64 44 41 8b 84 60 0e 50 43 d9 bf .D...dDA..`.PC..
00000000678978a2: 00 00 00 00 00 00 00 83 01 73 00 93 00 00 00 00 .........s......
00000000b28b247c: 99 29 1d 38 00 00 00 00 99 29 1d 40 00 00 00 00 .).8.....).@....
000000002b2a662c: 99 29 1d 48 00 00 00 00 99 49 11 00 00 00 00 00 .).H.....I......
00000000ea2ffbb8: 99 49 11 08 00 00 45 25 99 49 11 10 00 00 48 fe .I....E%.I....H.
0000000069e86440: 99 49 11 18 00 00 4c 6b 99 49 11 20 00 00 4d 97 .I....Lk.I. ..M.
XFS (dm-0): xfs_do_force_shutdown(0x8) called from line 1423 of file fs/xfs/xfs_buf.c. Return address = 00000000c0ff63c1
XFS (dm-0): Corruption of in-memory data detected. Shutting down filesystem
XFS (dm-0): Please umount the filesystem and rectify the problem(s)

>From the log above, we know xfs_buf->b_no is 0x178, but the block's hdr record
its blkno is 0x1a0.

Fixes: 24df33b45ecf ("xfs: add CRC checking to dir2 leaf blocks")
Signed-off-by: Zhang Tianci <zhangtianci.1997@bytedance.com>
Suggested-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e702a5d Wed Jul 11 23:26:12 MDT 2018 Brian Foster <bfoster@redhat.com> 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>
diff 6ee49a20 Wed Oct 01 17:23:49 MDT 2014 Eric Sandeen <sandeen@sandeen.net> xfs: don't send null bp to xfs_trans_brelse()

In this case, if bp is NULL, error is set, and we send a
NULL bp to xfs_trans_brelse, which will try to dereference it.

Test whether we actually have a buffer before we try to
free it.

Coverity spotted this.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
H A Dxfs_inode_buf.cdiff 6b69e485 Wed May 12 01:49:19 MDT 2021 Darrick J. Wong <djwong@kernel.org> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6a96c565 Fri Mar 23 11:06:56 MDT 2018 Darrick J. Wong <darrick.wong@oracle.com> xfs: don't accept inode buffers with suspicious unlinked chains

When we're verifying inode buffers, sanity-check the unlinked pointer.
We don't want to run the risk of trying to purge something that's
obviously broken.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 6edb1810 Fri Mar 23 11:06:53 MDT 2018 Darrick J. Wong <darrick.wong@oracle.com> xfs: refactor inode buffer verifier error logging

When the inode buffer verifier encounters an error, it's much more
helpful to print a buffer from the offending inode instead of just the
start of the inode chunk buffer.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
H A Dxfs_inode_buf.hdiff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
H A Dxfs_inode_fork.cdiff 6e145f94 Tue Dec 19 23:34:55 MST 2023 Christoph Hellwig <hch@lst.de> xfs: make if_data a void pointer

The xfs_ifork structure currently has a union of the if_root void pointer
and the if_data char pointer. In either case it is an opaque pointer
that depends on the fork format. Replace the union with a single if_data
void pointer as that is what almost all callers want. Only the symlink
NULL termination code in xfs_init_local_fork actually needs a new local
variable now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 6a3bd8fc Tue Apr 11 20:00:05 MDT 2023 Darrick J. Wong <djwong@kernel.org> xfs: complain about bad file mapping records in the ondisk bmbt

Similar to what we've just done for the other btrees, create a function
to log corrupt bmbt records and call it whenever we encounter a bad
record in the ondisk btree.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff c78c2d09 Tue Jul 19 10:14:55 MDT 2022 Darrick J. Wong <djwong@kernel.org> xfs: don't leak memory when attr fork loading fails

I observed the following evidence of a memory leak while running xfs/399
from the xfs fsck test suite (edited for brevity):

XFS (sde): Metadata corruption detected at xfs_attr_shortform_verify_struct.part.0+0x7b/0xb0 [xfs], inode 0x1172 attr fork
XFS: Assertion failed: ip->i_af.if_u1.if_data == NULL, file: fs/xfs/libxfs/xfs_inode_fork.c, line: 315
------------[ cut here ]------------
WARNING: CPU: 2 PID: 91635 at fs/xfs/xfs_message.c:104 assfail+0x46/0x4a [xfs]
CPU: 2 PID: 91635 Comm: xfs_scrub Tainted: G W 5.19.0-rc7-xfsx #rc7 6e6475eb29fd9dda3181f81b7ca7ff961d277a40
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:assfail+0x46/0x4a [xfs]
Call Trace:
<TASK>
xfs_ifork_zap_attr+0x7c/0xb0
xfs_iformat_attr_fork+0x86/0x110
xfs_inode_from_disk+0x41d/0x480
xfs_iget+0x389/0xd70
xfs_bulkstat_one_int+0x5b/0x540
xfs_bulkstat_iwalk+0x1e/0x30
xfs_iwalk_ag_recs+0xd1/0x160
xfs_iwalk_run_callbacks+0xb9/0x180
xfs_iwalk_ag+0x1d8/0x2e0
xfs_iwalk+0x141/0x220
xfs_bulkstat+0x105/0x180
xfs_ioc_bulkstat.constprop.0.isra.0+0xc5/0x130
xfs_file_ioctl+0xa5f/0xef0
__x64_sys_ioctl+0x82/0xa0
do_syscall_64+0x2b/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0

This newly-added assertion checks that there aren't any incore data
structures hanging off the incore fork when we're trying to reset its
contents. From the call trace, it is evident that iget was trying to
construct an incore inode from the ondisk inode, but the attr fork
verifier failed and we were trying to undo all the memory allocations
that we had done earlier.

The three assertions in xfs_ifork_zap_attr check that the caller has
already called xfs_idestroy_fork, which clearly has not been done here.
As the zap function then zeroes the pointers, we've effectively leaked
the memory.

The shortest change would have been to insert an extra call to
xfs_idestroy_fork, but it makes more sense to bundle the _idestroy_fork
call into _zap_attr, since all other callsites call _idestroy_fork
immediately prior to calling _zap_attr. IOWs, it eliminates one way to
fail.

Note: This change only applies cleanly to 2ed5b09b3e8f, since we just
reworked the attr fork lifetime. However, I think this memory leak has
existed since 0f45a1b20cd8, since the chain xfs_iformat_attr_fork ->
xfs_iformat_local -> xfs_init_local_fork will allocate
ifp->if_u1.if_data, but if xfs_ifork_verify_local_attr fails,
xfs_iformat_attr_fork will free i_afp without freeing any of the stuff
hanging off i_afp. The solution for older kernels I think is to add the
missing call to xfs_idestroy_fork just prior to calling kmem_cache_free.

Found by fuzzing a.sfattr.hdr.totsize = lastbit in xfs/399.

Fixes: 2ed5b09b3e8f ("xfs: make inode attribute forks a permanent part of struct xfs_inode")
Probably-Fixes: 0f45a1b20cd8 ("xfs: improve local fork verification")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6bdcf26a Fri Nov 03 11:34:46 MDT 2017 Christoph Hellwig <hch@lst.de> 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>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
/linux-master/fs/xfs/
H A Dxfs_bmap_util.cdiff 6b700a5b Mon Apr 15 15:54:11 MDT 2024 Darrick J. Wong <djwong@kernel.org> xfs: hoist multi-fsb allocation unit detection to a helper

Replace the open-coded logic to decide if a file has a multi-fsb
allocation unit to a helper to make the code easier to read.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e702a5d Wed Jul 11 23:26:12 MDT 2018 Brian Foster <bfoster@redhat.com> 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>
diff 6b18af0d Thu Oct 19 12:07:10 MDT 2017 Christoph Hellwig <hch@lst.de> xfs: remove XFS_BMAP_MAX_SHIFT_EXTENTS

The define was always set to 1, which means looping until we reach is
was dead code from the start.

Also remove an initialization of next_fsb for the done case that doesn't
fit the new code flow - it was never checked by the caller in the done
case to start with.

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>
diff 6fb10d6d Tue Aug 29 11:08:39 MDT 2017 Brian Foster <bfoster@redhat.com> xfs: move bmbt owner change to last step of extent swap

The extent swap operation currently resets bmbt block owners before
the inode forks are swapped. The bmbt buffers are marked as ordered
so they do not have to be physically logged in the transaction.

This use of ordered buffers is not safe as bmbt buffers may have
been previously physically logged. The bmbt owner change algorithm
needs to be updated to physically log buffers that are already dirty
when/if they are encountered. This means that an extent swap will
eventually require multiple rolling transactions to handle large
btrees. In addition, all inode related changes must be logged before
the bmbt owner change scan begins and can roll the transaction for
the first time to preserve fs consistency via log recovery.

In preparation for such fixes to the bmbt owner change algorithm,
refactor the bmbt scan out of the extent fork swap code to the last
operation before the transaction is committed. Update
xfs_swap_extent_forks() to only set the inode log flags when an
owner change scan is necessary. Update xfs_swap_extents() to trigger
the owner change based on the inode log flags. Note that since the
owner change now occurs after the extent fork swap, the inode btrees
must be fixed up with the inode number of the current inode (similar
to log recovery).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 6eadbf4c Fri May 12 11:44:08 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: BMAPX shouldn't barf on inline-format directories

When we're fulfilling a BMAPX request, jump out early if the data fork
is in local format. This prevents us from hitting a debugging check in
bmapi_read and barfing errors back to userspace. The on-disk extent
count check later isn't sufficient for IF_DELALLOC mode because da
extents are in memory and not on disk.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 4dfce57d Mon Nov 07 06:55:18 MST 2016 Eric Sandeen <sandeen@sandeen.net> xfs: fix up xfs_swap_extent_forks inline extent handling

There have been several reports over the years of NULL pointer
dereferences in xfs_trans_log_inode during xfs_fsr processes,
when the process is doing an fput and tearing down extents
on the temporary inode, something like:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
PID: 29439 TASK: ffff880550584fa0 CPU: 6 COMMAND: "xfs_fsr"
[exception RIP: xfs_trans_log_inode+0x10]
#9 [ffff8800a57bbbe0] xfs_bunmapi at ffffffffa037398e [xfs]
#10 [ffff8800a57bbce8] xfs_itruncate_extents at ffffffffa0391b29 [xfs]
#11 [ffff8800a57bbd88] xfs_inactive_truncate at ffffffffa0391d0c [xfs]
#12 [ffff8800a57bbdb8] xfs_inactive at ffffffffa0392508 [xfs]
#13 [ffff8800a57bbdd8] xfs_fs_evict_inode at ffffffffa035907e [xfs]
#14 [ffff8800a57bbe00] evict at ffffffff811e1b67
#15 [ffff8800a57bbe28] iput at ffffffff811e23a5
#16 [ffff8800a57bbe58] dentry_kill at ffffffff811dcfc8
#17 [ffff8800a57bbe88] dput at ffffffff811dd06c
#18 [ffff8800a57bbea8] __fput at ffffffff811c823b
#19 [ffff8800a57bbef0] ____fput at ffffffff811c846e
#20 [ffff8800a57bbf00] task_work_run at ffffffff81093b27
#21 [ffff8800a57bbf30] do_notify_resume at ffffffff81013b0c
#22 [ffff8800a57bbf50] int_signal at ffffffff8161405d

As it turns out, this is because the i_itemp pointer, along
with the d_ops pointer, has been overwritten with zeros
when we tear down the extents during truncate. When the in-core
inode fork on the temporary inode used by xfs_fsr was originally
set up during the extent swap, we mistakenly looked at di_nextents
to determine whether all extents fit inline, but this misses extents
generated by speculative preallocation; we should be using if_bytes
instead.

This mistake corrupts the in-memory inode, and code in
xfs_iext_remove_inline eventually gets bad inputs, causing
it to memmove and memset incorrect ranges; this became apparent
because the two values in ifp->if_u2.if_inline_ext[1] contained
what should have been in d_ops and i_itemp; they were memmoved due
to incorrect array indexing and then the original locations
were zeroed with memset, again due to an array overrun.

Fix this by properly using i_df.if_bytes to determine the number
of extents, not di_nextents.

Thanks to dchinner for looking at this with me and spotting the
root cause.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6bc43af3 Tue Aug 18 17:51:43 MDT 2015 Brian Foster <bfoster@redhat.com> xfs: ensure EFD trans aborts on log recovery extent free failure

Log recovery attempts to free extents with leftover EFIs in the AIL
after initial processing. If the extent free fails (e.g., due to
unrelated fs corruption), the transaction is cancelled, though it
might not be dirtied at the time. If this is the case, the EFD does
not abort and thus does not release the EFI. This can lead to hangs
as the EFI pins the AIL.

Update xlog_recover_process_efi() to log the EFD in the transaction
before xfs_free_extent() errors are handled to ensure the
transaction is dirty, aborts the EFD and releases the EFI on error.
Since this is a requirement for EFD processing (and consistent with
xfs_bmap_finish()), update the EFD logging helper to do the extent
free and unconditionally log the EFD. This encodes the required EFD
logging behavior into the helper and reduces the likelihood of
errors down the road.

[dchinner: re-add xfs_alloc.h to xfs_log_recover.c to fix build
failure.]

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
H A Dxfs_icache.cdiff e33c267a Tue May 31 21:22:24 MDT 2022 Roman Gushchin <roman.gushchin@linux.dev> mm: shrinkers: provide shrinkers with names

Currently shrinkers are anonymous objects. For debugging purposes they
can be identified by count/scan function names, but it's not always
useful: e.g. for superblock's shrinkers it's nice to have at least an
idea of to which superblock the shrinker belongs.

This commit adds names to shrinkers. register_shrinker() and
prealloc_shrinker() functions are extended to take a format and arguments
to master a name.

In some cases it's not possible to determine a good name at the time when
a shrinker is allocated. For such cases shrinker_debugfs_rename() is
provided.

The expected format is:
<subsystem>-<shrinker_type>[:<instance>]-<id>
For some shrinkers an instance can be encoded as (MAJOR:MINOR) pair.

After this change the shrinker debugfs directory looks like:
$ cd /sys/kernel/debug/shrinker/
$ ls
dquota-cache-16 sb-devpts-28 sb-proc-47 sb-tmpfs-42
mm-shadow-18 sb-devtmpfs-5 sb-proc-48 sb-tmpfs-43
mm-zspool:zram0-34 sb-hugetlbfs-17 sb-pstore-31 sb-tmpfs-44
rcu-kfree-0 sb-hugetlbfs-33 sb-rootfs-2 sb-tmpfs-49
sb-aio-20 sb-iomem-12 sb-securityfs-6 sb-tracefs-13
sb-anon_inodefs-15 sb-mqueue-21 sb-selinuxfs-22 sb-xfs:vda1-36
sb-bdev-3 sb-nsfs-4 sb-sockfs-8 sb-zsmalloc-19
sb-bpf-32 sb-pipefs-14 sb-sysfs-26 thp-deferred_split-10
sb-btrfs:vda2-24 sb-proc-25 sb-tmpfs-1 thp-zero-9
sb-cgroup2-30 sb-proc-39 sb-tmpfs-27 xfs-buf:vda1-37
sb-configfs-23 sb-proc-41 sb-tmpfs-29 xfs-inodegc:vda1-38
sb-dax-11 sb-proc-45 sb-tmpfs-35
sb-debugfs-7 sb-proc-46 sb-tmpfs-40

[roman.gushchin@linux.dev: fix build warnings]
Link: https://lkml.kernel.org/r/Yr+ZTnLb9lJk6fJO@castle
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lkml.kernel.org/r/20220601032227.4076670-4-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff c78c2d09 Tue Jul 19 10:14:55 MDT 2022 Darrick J. Wong <djwong@kernel.org> xfs: don't leak memory when attr fork loading fails

I observed the following evidence of a memory leak while running xfs/399
from the xfs fsck test suite (edited for brevity):

XFS (sde): Metadata corruption detected at xfs_attr_shortform_verify_struct.part.0+0x7b/0xb0 [xfs], inode 0x1172 attr fork
XFS: Assertion failed: ip->i_af.if_u1.if_data == NULL, file: fs/xfs/libxfs/xfs_inode_fork.c, line: 315
------------[ cut here ]------------
WARNING: CPU: 2 PID: 91635 at fs/xfs/xfs_message.c:104 assfail+0x46/0x4a [xfs]
CPU: 2 PID: 91635 Comm: xfs_scrub Tainted: G W 5.19.0-rc7-xfsx #rc7 6e6475eb29fd9dda3181f81b7ca7ff961d277a40
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:assfail+0x46/0x4a [xfs]
Call Trace:
<TASK>
xfs_ifork_zap_attr+0x7c/0xb0
xfs_iformat_attr_fork+0x86/0x110
xfs_inode_from_disk+0x41d/0x480
xfs_iget+0x389/0xd70
xfs_bulkstat_one_int+0x5b/0x540
xfs_bulkstat_iwalk+0x1e/0x30
xfs_iwalk_ag_recs+0xd1/0x160
xfs_iwalk_run_callbacks+0xb9/0x180
xfs_iwalk_ag+0x1d8/0x2e0
xfs_iwalk+0x141/0x220
xfs_bulkstat+0x105/0x180
xfs_ioc_bulkstat.constprop.0.isra.0+0xc5/0x130
xfs_file_ioctl+0xa5f/0xef0
__x64_sys_ioctl+0x82/0xa0
do_syscall_64+0x2b/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0

This newly-added assertion checks that there aren't any incore data
structures hanging off the incore fork when we're trying to reset its
contents. From the call trace, it is evident that iget was trying to
construct an incore inode from the ondisk inode, but the attr fork
verifier failed and we were trying to undo all the memory allocations
that we had done earlier.

The three assertions in xfs_ifork_zap_attr check that the caller has
already called xfs_idestroy_fork, which clearly has not been done here.
As the zap function then zeroes the pointers, we've effectively leaked
the memory.

The shortest change would have been to insert an extra call to
xfs_idestroy_fork, but it makes more sense to bundle the _idestroy_fork
call into _zap_attr, since all other callsites call _idestroy_fork
immediately prior to calling _zap_attr. IOWs, it eliminates one way to
fail.

Note: This change only applies cleanly to 2ed5b09b3e8f, since we just
reworked the attr fork lifetime. However, I think this memory leak has
existed since 0f45a1b20cd8, since the chain xfs_iformat_attr_fork ->
xfs_iformat_local -> xfs_init_local_fork will allocate
ifp->if_u1.if_data, but if xfs_ifork_verify_local_attr fails,
xfs_iformat_attr_fork will free i_afp without freeing any of the stuff
hanging off i_afp. The solution for older kernels I think is to add the
missing call to xfs_idestroy_fork just prior to calling kmem_cache_free.

Found by fuzzing a.sfattr.hdr.totsize = lastbit in xfs/399.

Fixes: 2ed5b09b3e8f ("xfs: make inode attribute forks a permanent part of struct xfs_inode")
Probably-Fixes: 0f45a1b20cd8 ("xfs: improve local fork verification")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 6f649091 Fri Aug 06 12:05:42 MDT 2021 Darrick J. Wong <djwong@kernel.org> xfs: don't run speculative preallocation gc when fs is frozen

Now that we have the infrastructure to switch background workers on and
off at will, fix the block gc worker code so that we don't actually run
the worker when the filesystem is frozen, same as we do for deferred
inactivation.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6ca1c906 Mon Aug 12 04:49:26 MDT 2013 Dave Chinner <dchinner@redhat.com> xfs: separate dquot on disk format definitions out of xfs_quota.h

The on disk format definitions of the on-disk dquot, log formats and
quota off log formats are all intertwined with other definitions for
quotas. Separate them out into their own header file so they can
easily be shared with userspace.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
6d8b79cf Mon Oct 08 04:56:09 MDT 2012 Dave Chinner <dchinner@redhat.com> xfs: rename xfs_sync.[ch] to xfs_icache.[ch]

xfs_sync.c now only contains inode reclaim functions and inode cache
iteration functions. It is not related to sync operations anymore.
Rename to xfs_icache.c to reflect it's contents and prepare for
consolidation with the other inode cache file that exists
(xfs_iget.c).

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
H A Dxfs_inode.cdiff 6a94b1ac Mon Apr 22 05:20:19 MDT 2024 Christoph Hellwig <hch@lst.de> xfs: reinstate delalloc for RT inodes (if sb_rextsize == 1)

Commit aff3a9edb708 ("xfs: Use preallocation for inodes with extsz
hints") disabled delayed allocation for all inodes with extent size
hints due a data exposure problem. It turns out we fixed this data
exposure problem since by always creating unwritten extents for
delalloc conversions due to more data exposure problems, but the
writeback path doesn't actually support extent size hints when
converting delalloc these days, which probably isn't a problem given
that people using the hints know what they get.

However due to the way how xfs_get_extsz_hint is implemented, it
always claims an extent size hint for RT inodes even if the RT
extent size is a single FSB. Due to that the above commit effectively
disabled delalloc support for RT inodes.

Switch xfs_get_extsz_hint to return 0 for this case and work around
that in a few places to reinstate delalloc support for RT inodes on
file systems with an sb_rextsize of 1.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 6e145f94 Tue Dec 19 23:34:55 MST 2023 Christoph Hellwig <hch@lst.de> xfs: make if_data a void pointer

The xfs_ifork structure currently has a union of the if_root void pointer
and the if_data char pointer. In either case it is an opaque pointer
that depends on the fork format. Replace the union with a single if_data
void pointer as that is what almost all callers want. Only the symlink
NULL termination code in xfs_init_local_fork actually needs a new local
variable now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 6f5097e3 Sun May 29 18:56:33 MDT 2022 Brian Foster <bfoster@redhat.com> xfs: fix xfs_ifree() error handling to not leak perag ref

For some reason commit 9a5280b312e2e ("xfs: reorder iunlink remove
operation in xfs_ifree") replaced a jump to the exit path in the
event of an xfs_difree() error with a direct return, which skips
releasing the perag reference acquired at the top of the function.
Restore the original code to drop the reference on error.

Fixes: 9a5280b312e2e ("xfs: reorder iunlink remove operation in xfs_ifree")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6da1b4b1 Fri Jan 22 17:48:32 MST 2021 Darrick J. Wong <darrick.wong@oracle.com> xfs: fix an ABBA deadlock in xfs_rename

When overlayfs is running on top of xfs and the user unlinks a file in
the overlay, overlayfs will create a whiteout inode and ask xfs to
"rename" the whiteout file atop the one being unlinked. If the file
being unlinked loses its one nlink, we then have to put the inode on the
unlinked list.

This requires us to grab the AGI buffer of the whiteout inode to take it
off the unlinked list (which is where whiteouts are created) and to grab
the AGI buffer of the file being deleted. If the whiteout was created
in a higher numbered AG than the file being deleted, we'll lock the AGIs
in the wrong order and deadlock.

Therefore, grab all the AGI locks we think we'll need ahead of time, and
in order of increasing AG number per the locking rules.

Reported-by: wenli xie <wlxie7296@gmail.com>
Fixes: 93597ae8dac0 ("xfs: Fix deadlock between AGI and AGF when target_ip exists in xfs_rename()")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff 6dd379c7 Tue Sep 15 21:44:46 MDT 2020 Brian Foster <bfoster@redhat.com> xfs: drop extra transaction roll from inode extent truncate

The inode extent truncate path unmaps extents from the inode block
mapping, finishes deferred ops to free the associated extents and
then explicitly rolls the transaction before processing the next
extent. The latter extent roll is spurious as xfs_defer_finish()
always returns a clean transaction and automatically relogs inodes
attached to the transaction (with lock_flags == 0). This can
unnecessarily increase the number of log ticket regrants that occur
during a long running truncate operation. Remove the explicit
transaction roll.

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>
diff 6aa67184 Wed Jul 11 23:26:07 MDT 2018 Brian Foster <bfoster@redhat.com> xfs: rename xfs_trans ->t_agfl_dfops to ->t_dfops

The ->t_agfl_dfops field is currently used to defer agfl block frees
from associated transaction contexts. While all known problematic
contexts have already been updated to use ->t_agfl_dfops, the
broader goal is defer agfl frees from all callers that already use a
deferred operations structure. Further, the transaction field
facilitates a good amount of code clean up where the transaction and
dfops have historically been passed down through the stack
separately.

Rename the field to something more generic to prepare to use it as
such throughout XFS. This patch does not change behavior.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 6bdcf26a Fri Nov 03 11:34:46 MDT 2017 Christoph Hellwig <hch@lst.de> 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>
diff 6e3e6d55 Tue Apr 05 17:47:21 MDT 2016 Eryu Guan <guaneryu@gmail.com> xfs: mute some sparse warnings

These three warnings are fixed:

fs/xfs/xfs_inode.c:1033:44: warning: Using plain integer as NULL pointer
fs/xfs/xfs_inode_item.c:525:20: warning: context imbalance in 'xfs_inode_item_push' - unexpected unlock
fs/xfs/xfs_dquot.c:696:1: warning: symbol 'xfs_dq_get_next_id' was not declared. Should it be static?

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
H A Dxfs_inode.hdiff 6b700a5b Mon Apr 15 15:54:11 MDT 2024 Darrick J. Wong <djwong@kernel.org> xfs: hoist multi-fsb allocation unit detection to a helper

Replace the open-coded logic to decide if a file has a multi-fsb
allocation unit to a helper to make the code easier to read.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6e857567 Wed Dec 22 06:02:31 MST 2010 Dave Chinner <dchinner@redhat.com> xfs: don't truncate prealloc from frequently accessed inodes

A long standing problem for streaming writeѕ through the NFS server
has been that the NFS server opens and closes file descriptors on an
inode for every write. The result of this behaviour is that the
->release() function is called on every close and that results in
XFS truncating speculative preallocation beyond the EOF. This has
an adverse effect on file layout when multiple files are being
written at the same time - they interleave their extents and can
result in severe fragmentation.

To avoid this problem, keep track of ->release calls made on a dirty
inode. For most cases, an inode is only going to be opened once for
writing and then closed again during it's lifetime in cache. Hence
if there are multiple ->release calls when the inode is dirty, there
is a good chance that the inode is being accessed by the NFS server.
Hence set a flag the first time ->release is called while there are
delalloc blocks still outstanding on the inode.

If this flag is set when ->release is next called, then do no
truncate away the speculative preallocation - leave it there so that
subsequent writes do not need to reallocate the delalloc space. This
will prevent interleaving of extents of different inodes written
concurrently to the same AG.

If we get this wrong, it is not a big deal as we truncate
speculative allocation beyond EOF anyway in xfs_inactive() when the
inode is thrown out of the cache.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff 6c77b0ea Wed Oct 06 12:41:17 MDT 2010 Christoph Hellwig <hch@infradead.org> xfs: remove xfs_cred.h

We're not actually passing around credentials inside XFS for a while
now, so remove all xfs_cred.h with it's cred_t typedef and all
instances of it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
diff 0b1b213f Mon Dec 14 16:14:59 MST 2009 Christoph Hellwig <hch@infradead.org> xfs: event tracing support

Convert the old xfs tracing support that could only be used with the
out of tree kdb and xfsidbg patches to use the generic event tracer.

To use it make sure CONFIG_EVENT_TRACING is enabled and then enable
all xfs trace channels by:

echo 1 > /sys/kernel/debug/tracing/events/xfs/enable

or alternatively enable single events by just doing the same in one
event subdirectory, e.g.

echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable

or set more complex filters, etc. In Documentation/trace/events.txt
all this is desctribed in more detail. To reads the events do a

cat /sys/kernel/debug/tracing/trace

Compared to the last posting this patch converts the tracing mostly to
the one tracepoint per callsite model that other users of the new
tracing facility also employ. This allows a very fine-grained control
of the tracing, a cleaner output of the traces and also enables the
perf tool to use each tracepoint as a virtual performance counter,
allowing us to e.g. count how often certain workloads git various
spots in XFS. Take a look at

http://lwn.net/Articles/346470/

for some examples.

Also the btree tracing isn't included at all yet, as it will require
additional core tracing features not in mainline yet, I plan to
deliver it later.

And the really nice thing about this patch is that it actually removes
many lines of code while adding this nice functionality:

fs/xfs/Makefile | 8
fs/xfs/linux-2.6/xfs_acl.c | 1
fs/xfs/linux-2.6/xfs_aops.c | 52 -
fs/xfs/linux-2.6/xfs_aops.h | 2
fs/xfs/linux-2.6/xfs_buf.c | 117 +--
fs/xfs/linux-2.6/xfs_buf.h | 33
fs/xfs/linux-2.6/xfs_fs_subr.c | 3
fs/xfs/linux-2.6/xfs_ioctl.c | 1
fs/xfs/linux-2.6/xfs_ioctl32.c | 1
fs/xfs/linux-2.6/xfs_iops.c | 1
fs/xfs/linux-2.6/xfs_linux.h | 1
fs/xfs/linux-2.6/xfs_lrw.c | 87 --
fs/xfs/linux-2.6/xfs_lrw.h | 45 -
fs/xfs/linux-2.6/xfs_super.c | 104 ---
fs/xfs/linux-2.6/xfs_super.h | 7
fs/xfs/linux-2.6/xfs_sync.c | 1
fs/xfs/linux-2.6/xfs_trace.c | 75 ++
fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++
fs/xfs/linux-2.6/xfs_vnode.h | 4
fs/xfs/quota/xfs_dquot.c | 110 ---
fs/xfs/quota/xfs_dquot.h | 21
fs/xfs/quota/xfs_qm.c | 40 -
fs/xfs/quota/xfs_qm_syscalls.c | 4
fs/xfs/support/ktrace.c | 323 ---------
fs/xfs/support/ktrace.h | 85 --
fs/xfs/xfs.h | 16
fs/xfs/xfs_ag.h | 14
fs/xfs/xfs_alloc.c | 230 +-----
fs/xfs/xfs_alloc.h | 27
fs/xfs/xfs_alloc_btree.c | 1
fs/xfs/xfs_attr.c | 107 ---
fs/xfs/xfs_attr.h | 10
fs/xfs/xfs_attr_leaf.c | 14
fs/xfs/xfs_attr_sf.h | 40 -
fs/xfs/xfs_bmap.c | 507 +++------------
fs/xfs/xfs_bmap.h | 49 -
fs/xfs/xfs_bmap_btree.c | 6
fs/xfs/xfs_btree.c | 5
fs/xfs/xfs_btree_trace.h | 17
fs/xfs/xfs_buf_item.c | 87 --
fs/xfs/xfs_buf_item.h | 20
fs/xfs/xfs_da_btree.c | 3
fs/xfs/xfs_da_btree.h | 7
fs/xfs/xfs_dfrag.c | 2
fs/xfs/xfs_dir2.c | 8
fs/xfs/xfs_dir2_block.c | 20
fs/xfs/xfs_dir2_leaf.c | 21
fs/xfs/xfs_dir2_node.c | 27
fs/xfs/xfs_dir2_sf.c | 26
fs/xfs/xfs_dir2_trace.c | 216 ------
fs/xfs/xfs_dir2_trace.h | 72 --
fs/xfs/xfs_filestream.c | 8
fs/xfs/xfs_fsops.c | 2
fs/xfs/xfs_iget.c | 111 ---
fs/xfs/xfs_inode.c | 67 --
fs/xfs/xfs_inode.h | 76 --
fs/xfs/xfs_inode_item.c | 5
fs/xfs/xfs_iomap.c | 85 --
fs/xfs/xfs_iomap.h | 8
fs/xfs/xfs_log.c | 181 +----
fs/xfs/xfs_log_priv.h | 20
fs/xfs/xfs_log_recover.c | 1
fs/xfs/xfs_mount.c | 2
fs/xfs/xfs_quota.h | 8
fs/xfs/xfs_rename.c | 1
fs/xfs/xfs_rtalloc.c | 1
fs/xfs/xfs_rw.c | 3
fs/xfs/xfs_trans.h | 47 +
fs/xfs/xfs_trans_buf.c | 62 -
fs/xfs/xfs_vnodeops.c | 8
70 files changed, 2151 insertions(+), 2592 deletions(-)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
diff 6ef35544 Tue Nov 24 17:00:21 MST 2009 Christoph Hellwig <hch@infradead.org> xfs: change the xfs_iext_insert / xfs_iext_remove

Change the xfs_iext_insert / xfs_iext_remove prototypes to pass more
information which will allow pushing the trace points from the callers
into those functions. This includes folding the whichfork information
into the state variable to minimize the addition stack footprint.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
diff 6d73cf13 Tue Dec 09 02:47:32 MST 2008 Christoph Hellwig <hch@infradead.org> [XFS] resync headers with libxfs

- xfs_sb.h add the XFS_SB_VERSION2_PARENTBIT features2 that has been
around in userspace for some time
- xfs_inode.h: move a few things out of __KERNEL__ that are needed by
userspace
- xfs_mount.h: only include xfs_sync.h under __KERNEL__
- xfs_inode.c: minor whitespace fixup. I accidentaly changes this when
importing this file for use by userspace.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff 6bd16ff2 Tue Dec 02 16:20:32 MST 2008 Christoph Hellwig <hch@lst.de> kill dead inode flags

There are a few inode flags around that aren't used anywhere, so remove
them. Also update xfsidbg to display all used inode flags correctly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
H A Dxfs_inode_item.cdiff 6e145f94 Tue Dec 19 23:34:55 MST 2023 Christoph Hellwig <hch@lst.de> xfs: make if_data a void pointer

The xfs_ifork structure currently has a union of the if_root void pointer
and the if_data char pointer. In either case it is an opaque pointer
that depends on the fork format. Replace the union with a single if_data
void pointer as that is what almost all callers want. Only the symlink
NULL termination code in xfs_init_local_fork actually needs a new local
variable now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 6fc277c7 Wed Apr 21 14:48:27 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6af0479d Wed May 06 14:25:50 MDT 2020 Brian Foster <bfoster@redhat.com> xfs: drop unused shutdown parameter from xfs_trans_ail_remove()

The shutdown parameter of xfs_trans_ail_remove() is no longer used.
The remaining callers use it for items that legitimately might not
be in the AIL or from contexts where AIL state has already been
checked. Remove the unnecessary parameter and fix up the callers.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 6bdcf26a Fri Nov 03 11:34:46 MDT 2017 Christoph Hellwig <hch@lst.de> 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>
diff 6e3e6d55 Tue Apr 05 17:47:21 MDT 2016 Eryu Guan <guaneryu@gmail.com> xfs: mute some sparse warnings

These three warnings are fixed:

fs/xfs/xfs_inode.c:1033:44: warning: Using plain integer as NULL pointer
fs/xfs/xfs_inode_item.c:525:20: warning: context imbalance in 'xfs_inode_item_push' - unexpected unlock
fs/xfs/xfs_dquot.c:696:1: warning: symbol 'xfs_dq_get_next_id' was not declared. Should it be static?

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 0b1b213f Mon Dec 14 16:14:59 MST 2009 Christoph Hellwig <hch@infradead.org> xfs: event tracing support

Convert the old xfs tracing support that could only be used with the
out of tree kdb and xfsidbg patches to use the generic event tracer.

To use it make sure CONFIG_EVENT_TRACING is enabled and then enable
all xfs trace channels by:

echo 1 > /sys/kernel/debug/tracing/events/xfs/enable

or alternatively enable single events by just doing the same in one
event subdirectory, e.g.

echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable

or set more complex filters, etc. In Documentation/trace/events.txt
all this is desctribed in more detail. To reads the events do a

cat /sys/kernel/debug/tracing/trace

Compared to the last posting this patch converts the tracing mostly to
the one tracepoint per callsite model that other users of the new
tracing facility also employ. This allows a very fine-grained control
of the tracing, a cleaner output of the traces and also enables the
perf tool to use each tracepoint as a virtual performance counter,
allowing us to e.g. count how often certain workloads git various
spots in XFS. Take a look at

http://lwn.net/Articles/346470/

for some examples.

Also the btree tracing isn't included at all yet, as it will require
additional core tracing features not in mainline yet, I plan to
deliver it later.

And the really nice thing about this patch is that it actually removes
many lines of code while adding this nice functionality:

fs/xfs/Makefile | 8
fs/xfs/linux-2.6/xfs_acl.c | 1
fs/xfs/linux-2.6/xfs_aops.c | 52 -
fs/xfs/linux-2.6/xfs_aops.h | 2
fs/xfs/linux-2.6/xfs_buf.c | 117 +--
fs/xfs/linux-2.6/xfs_buf.h | 33
fs/xfs/linux-2.6/xfs_fs_subr.c | 3
fs/xfs/linux-2.6/xfs_ioctl.c | 1
fs/xfs/linux-2.6/xfs_ioctl32.c | 1
fs/xfs/linux-2.6/xfs_iops.c | 1
fs/xfs/linux-2.6/xfs_linux.h | 1
fs/xfs/linux-2.6/xfs_lrw.c | 87 --
fs/xfs/linux-2.6/xfs_lrw.h | 45 -
fs/xfs/linux-2.6/xfs_super.c | 104 ---
fs/xfs/linux-2.6/xfs_super.h | 7
fs/xfs/linux-2.6/xfs_sync.c | 1
fs/xfs/linux-2.6/xfs_trace.c | 75 ++
fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++
fs/xfs/linux-2.6/xfs_vnode.h | 4
fs/xfs/quota/xfs_dquot.c | 110 ---
fs/xfs/quota/xfs_dquot.h | 21
fs/xfs/quota/xfs_qm.c | 40 -
fs/xfs/quota/xfs_qm_syscalls.c | 4
fs/xfs/support/ktrace.c | 323 ---------
fs/xfs/support/ktrace.h | 85 --
fs/xfs/xfs.h | 16
fs/xfs/xfs_ag.h | 14
fs/xfs/xfs_alloc.c | 230 +-----
fs/xfs/xfs_alloc.h | 27
fs/xfs/xfs_alloc_btree.c | 1
fs/xfs/xfs_attr.c | 107 ---
fs/xfs/xfs_attr.h | 10
fs/xfs/xfs_attr_leaf.c | 14
fs/xfs/xfs_attr_sf.h | 40 -
fs/xfs/xfs_bmap.c | 507 +++------------
fs/xfs/xfs_bmap.h | 49 -
fs/xfs/xfs_bmap_btree.c | 6
fs/xfs/xfs_btree.c | 5
fs/xfs/xfs_btree_trace.h | 17
fs/xfs/xfs_buf_item.c | 87 --
fs/xfs/xfs_buf_item.h | 20
fs/xfs/xfs_da_btree.c | 3
fs/xfs/xfs_da_btree.h | 7
fs/xfs/xfs_dfrag.c | 2
fs/xfs/xfs_dir2.c | 8
fs/xfs/xfs_dir2_block.c | 20
fs/xfs/xfs_dir2_leaf.c | 21
fs/xfs/xfs_dir2_node.c | 27
fs/xfs/xfs_dir2_sf.c | 26
fs/xfs/xfs_dir2_trace.c | 216 ------
fs/xfs/xfs_dir2_trace.h | 72 --
fs/xfs/xfs_filestream.c | 8
fs/xfs/xfs_fsops.c | 2
fs/xfs/xfs_iget.c | 111 ---
fs/xfs/xfs_inode.c | 67 --
fs/xfs/xfs_inode.h | 76 --
fs/xfs/xfs_inode_item.c | 5
fs/xfs/xfs_iomap.c | 85 --
fs/xfs/xfs_iomap.h | 8
fs/xfs/xfs_log.c | 181 +----
fs/xfs/xfs_log_priv.h | 20
fs/xfs/xfs_log_recover.c | 1
fs/xfs/xfs_mount.c | 2
fs/xfs/xfs_quota.h | 8
fs/xfs/xfs_rename.c | 1
fs/xfs/xfs_rtalloc.c | 1
fs/xfs/xfs_rw.c | 3
fs/xfs/xfs_trans.h | 47 +
fs/xfs/xfs_trans_buf.c | 62 -
fs/xfs/xfs_vnodeops.c | 8
70 files changed, 2151 insertions(+), 2592 deletions(-)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
diff 6d192a9b Thu Jun 08 22:55:38 MDT 2006 Tim Shimmin <tes@sgi.com> [XFS] inode items and EFI/EFDs have different ondisk format for 32bit and
64bit kernels allow recovery to handle both versions and do the necessary
decoding

SGI-PV: 952214
SGI-Modid: xfs-linux-melb:xfs-kern:26011a

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
H A Dxfs_iops.cdiff 6a94b1ac Mon Apr 22 05:20:19 MDT 2024 Christoph Hellwig <hch@lst.de> xfs: reinstate delalloc for RT inodes (if sb_rextsize == 1)

Commit aff3a9edb708 ("xfs: Use preallocation for inodes with extsz
hints") disabled delayed allocation for all inodes with extent size
hints due a data exposure problem. It turns out we fixed this data
exposure problem since by always creating unwritten extents for
delalloc conversions due to more data exposure problems, but the
writeback path doesn't actually support extent size hints when
converting delalloc these days, which probably isn't a problem given
that people using the hints know what they get.

However due to the way how xfs_get_extsz_hint is implemented, it
always claims an extent size hint for RT inodes even if the RT
extent size is a single FSB. Due to that the above commit effectively
disabled delalloc support for RT inodes.

Switch xfs_get_extsz_hint to return 0 for this case and work around
that in a few places to reinstate delalloc support for RT inodes on
file systems with an sb_rextsize of 1.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
diff 6c960e68 Thu Jan 12 16:49:13 MST 2023 Christian Brauner <brauner@kernel.org> fs: port ->create() to pass mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
diff 35faf310 Tue Jun 21 08:14:51 MDT 2022 Christian Brauner <brauner@kernel.org> fs: port to iattr ownership update helpers

Earlier we introduced new helpers to abstract ownership update and
remove code duplication. This converts all filesystems supporting
idmapped mounts to make use of these new helpers.

For now we always pass the initial idmapping which makes the idmapping
functions these helpers call nops.

This is done because we currently always pass the actual value to be
written to i_{g,u}id via struct iattr. While this allowed us to treat
the {g,u}id values in struct iattr as values that can be directly
written to inode->i_{g,u}id it also increases the potential for
confusion for filesystems.

Now that we are have dedicated types to prevent this confusion we will
ultimately only map the value from the idmapped mount into a filesystem
value that can be written to inode->i_{g,u}id when the filesystem
actually updates the inode. So pass down the initial idmapping until we
finished that conversion at which point we pass down the mount's
idmapping.

No functional changes intended.

Link: https://lore.kernel.org/r/20220621141454.2914719-6-brauner@kernel.org
Cc: Seth Forshee <sforshee@digitalocean.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
CC: linux-fsdevel@vger.kernel.org
Reviewed-by: Seth Forshee <sforshee@digitalocean.com>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e2608df Wed Mar 07 16:26:44 MST 2018 Dan Williams <dan.j.williams@intel.com> xfs, dax: introduce xfs_dax_aops

In preparation for the dax implementation to start associating dax pages
to inodes via page->mapping, we need to provide a 'struct
address_space_operations' instance for dax. Otherwise, direct-I/O
triggers incorrect page cache assumptions and warnings like the
following:

WARNING: CPU: 27 PID: 1783 at fs/xfs/xfs_aops.c:1468
xfs_vm_set_page_dirty+0xf3/0x1b0 [xfs]
[..]
CPU: 27 PID: 1783 Comm: dma-collision Tainted: G O 4.15.0-rc2+ #984
[..]
Call Trace:
set_page_dirty_lock+0x40/0x60
bio_set_pages_dirty+0x37/0x50
iomap_dio_actor+0x2b7/0x3b0
? iomap_dio_zero+0x110/0x110
iomap_apply+0xa4/0x110
iomap_dio_rw+0x29e/0x3b0
? iomap_dio_zero+0x110/0x110
? xfs_file_dio_aio_read+0x7c/0x1a0 [xfs]
xfs_file_dio_aio_read+0x7c/0x1a0 [xfs]
xfs_file_read_iter+0xa0/0xc0 [xfs]
__vfs_read+0xf9/0x170
vfs_read+0xa6/0x150
SyS_pread64+0x93/0xb0
entry_SYSCALL_64_fastpath+0x1f/0x96

...where the default set_page_dirty() handler assumes that dirty state
is being tracked in 'struct page' flags.

Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Jan Kara <jack@suse.cz>
Suggested-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff 6eb0b8df Fri Jul 07 09:37:26 MDT 2017 Darrick J. Wong <darrick.wong@oracle.com> xfs: rename MAXPATHLEN to XFS_SYMLINK_MAXLEN

XFS has a maximum symlink target length of 1024 bytes; this is a
holdover from the Irix days. Unfortunately, the constant establishing
this is 'MAXPATHLEN' and is /not/ the same as the Linux MAXPATHLEN,
which is 4096.

The kernel enforces its 1024 byte MAXPATHLEN on symlink targets, but
xfsprogs picks up the (Linux) system 4096 byte MAXPATHLEN, which means
that xfs_repair doesn't complain about oversized symlinks.

Since this is an on-disk format constraint, put the define in the XFS
namespace and move everything over to use the new name.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
diff a528d35e Tue Jan 31 09:46:22 MST 2017 David Howells <dhowells@redhat.com> statx: Add a system call to make enhanced file info available

Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.

The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode. This change is propagated to the vfs_getattr*()
function.

Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.

========
OVERVIEW
========

The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.

A number of requests were gathered for features to be included. The
following have been included:

(1) Make the fields a consistent size on all arches and make them large.

(2) Spare space, request flags and information flags are provided for
future expansion.

(3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
__s64).

(4) Creation time: The SMB protocol carries the creation time, which could
be exported by Samba, which will in turn help CIFS make use of
FS-Cache as that can be used for coherency data (stx_btime).

This is also specified in NFSv4 as a recommended attribute and could
be exported by NFSD [Steve French].

(5) Lightweight stat: Ask for just those details of interest, and allow a
netfs (such as NFS) to approximate anything not of interest, possibly
without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
Dilger] (AT_STATX_DONT_SYNC).

(6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
its cached attributes are up to date [Trond Myklebust]
(AT_STATX_FORCE_SYNC).

And the following have been left out for future extension:

(7) Data version number: Could be used by userspace NFS servers [Aneesh
Kumar].

Can also be used to modify fill_post_wcc() in NFSD which retrieves
i_version directly, but has just called vfs_getattr(). It could get
it from the kstat struct if it used vfs_xgetattr() instead.

(There's disagreement on the exact semantics of a single field, since
not all filesystems do this the same way).

(8) BSD stat compatibility: Including more fields from the BSD stat such
as creation time (st_btime) and inode generation number (st_gen)
[Jeremy Allison, Bernd Schubert].

(9) Inode generation number: Useful for FUSE and userspace NFS servers
[Bernd Schubert].

(This was asked for but later deemed unnecessary with the
open-by-handle capability available and caused disagreement as to
whether it's a security hole or not).

(10) Extra coherency data may be useful in making backups [Andreas Dilger].

(No particular data were offered, but things like last backup
timestamp, the data version number and the DOS archive bit would come
into this category).

(11) Allow the filesystem to indicate what it can/cannot provide: A
filesystem can now say it doesn't support a standard stat feature if
that isn't available, so if, for instance, inode numbers or UIDs don't
exist or are fabricated locally...

(This requires a separate system call - I have an fsinfo() call idea
for this).

(12) Store a 16-byte volume ID in the superblock that can be returned in
struct xstat [Steve French].

(Deferred to fsinfo).

(13) Include granularity fields in the time data to indicate the
granularity of each of the times (NFSv4 time_delta) [Steve French].

(Deferred to fsinfo).

(14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
Note that the Linux IOC flags are a mess and filesystems such as Ext4
define flags that aren't in linux/fs.h, so translation in the kernel
may be a necessity (or, possibly, we provide the filesystem type too).

(Some attributes are made available in stx_attributes, but the general
feeling was that the IOC flags were to ext[234]-specific and shouldn't
be exposed through statx this way).

(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
Michael Kerrisk].

(Deferred, probably to fsinfo. Finding out if there's an ACL or
seclabal might require extra filesystem operations).

(16) Femtosecond-resolution timestamps [Dave Chinner].

(A __reserved field has been left in the statx_timestamp struct for
this - if there proves to be a need).

(17) A set multiple attributes syscall to go with this.

===============
NEW SYSTEM CALL
===============

The new system call is:

int ret = statx(int dfd,
const char *filename,
unsigned int flags,
unsigned int mask,
struct statx *buffer);

The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat(). There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.

Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):

(1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
respect.

(2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
its attributes with the server - which might require data writeback to
occur to get the timestamps correct.

(3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
network filesystem. The resulting values should be considered
approximate.

mask is a bitmask indicating the fields in struct statx that are of
interest to the caller. The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat(). It should be noted that asking for
more information may entail extra I/O operations.

buffer points to the destination for the data. This must be 256 bytes in
size.

======================
MAIN ATTRIBUTES RECORD
======================

The following structures are defined in which to return the main attribute
set:

struct statx_timestamp {
__s64 tv_sec;
__s32 tv_nsec;
__s32 __reserved;
};

struct statx {
__u32 stx_mask;
__u32 stx_blksize;
__u64 stx_attributes;
__u32 stx_nlink;
__u32 stx_uid;
__u32 stx_gid;
__u16 stx_mode;
__u16 __spare0[1];
__u64 stx_ino;
__u64 stx_size;
__u64 stx_blocks;
__u64 __spare1[1];
struct statx_timestamp stx_atime;
struct statx_timestamp stx_btime;
struct statx_timestamp stx_ctime;
struct statx_timestamp stx_mtime;
__u32 stx_rdev_major;
__u32 stx_rdev_minor;
__u32 stx_dev_major;
__u32 stx_dev_minor;
__u64 __spare2[14];
};

The defined bits in request_mask and stx_mask are:

STATX_TYPE Want/got stx_mode & S_IFMT
STATX_MODE Want/got stx_mode & ~S_IFMT
STATX_NLINK Want/got stx_nlink
STATX_UID Want/got stx_uid
STATX_GID Want/got stx_gid
STATX_ATIME Want/got stx_atime{,_ns}
STATX_MTIME Want/got stx_mtime{,_ns}
STATX_CTIME Want/got stx_ctime{,_ns}
STATX_INO Want/got stx_ino
STATX_SIZE Want/got stx_size
STATX_BLOCKS Want/got stx_blocks
STATX_BASIC_STATS [The stuff in the normal stat struct]
STATX_BTIME Want/got stx_btime{,_ns}
STATX_ALL [All currently available stuff]

stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.

Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution. Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.

The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does. The following
attributes map to FS_*_FL flags and are the same numerical value:

STATX_ATTR_COMPRESSED File is compressed by the fs
STATX_ATTR_IMMUTABLE File is marked immutable
STATX_ATTR_APPEND File is append-only
STATX_ATTR_NODUMP File is not to be dumped
STATX_ATTR_ENCRYPTED File requires key to decrypt in fs

Within the kernel, the supported flags are listed by:

KSTAT_ATTR_FS_IOC_FLAGS

[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]

New flags include:

STATX_ATTR_AUTOMOUNT Object is an automount trigger

These are for the use of GUI tools that might want to mark files specially,
depending on what they are.

Fields in struct statx come in a number of classes:

(0) stx_dev_*, stx_blksize.

These are local system information and are always available.

(1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
stx_size, stx_blocks.

These will be returned whether the caller asks for them or not. The
corresponding bits in stx_mask will be set to indicate whether they
actually have valid values.

If the caller didn't ask for them, then they may be approximated. For
example, NFS won't waste any time updating them from the server,
unless as a byproduct of updating something requested.

If the values don't actually exist for the underlying object (such as
UID or GID on a DOS file), then the bit won't be set in the stx_mask,
even if the caller asked for the value. In such a case, the returned
value will be a fabrication.

Note that there are instances where the type might not be valid, for
instance Windows reparse points.

(2) stx_rdev_*.

This will be set only if stx_mode indicates we're looking at a
blockdev or a chardev, otherwise will be 0.

(3) stx_btime.

Similar to (1), except this will be set to 0 if it doesn't exist.

=======
TESTING
=======

The following test program can be used to test the statx system call:

samples/statx/test-statx.c

Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.

Here's some example output. Firstly, an NFS directory that crosses to
another FSID. Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.

[root@andromeda ~]# /tmp/test-statx -A /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:26 Inode: 1703937 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)

Secondly, the result of automounting on that directory.

[root@andromeda ~]# /tmp/test-statx /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:27 Inode: 2 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 6b255391 Tue Nov 17 08:20:54 MST 2015 Al Viro <viro@zeniv.linux.org.uk> replace ->follow_link() with new method that could stay in RCU mode

new method: ->get_link(); replacement of ->follow_link(). The differences
are:
* inode and dentry are passed separately
* might be called both in RCU and non-RCU mode;
the former is indicated by passing it a NULL dentry.
* when called that way it isn't allowed to block
and should return ERR_PTR(-ECHILD) if it needs to be called
in non-RCU mode.

It's a flagday change - the old method is gone, all in-tree instances
converted. Conversion isn't hard; said that, so far very few instances
do not immediately bail out when called in RCU mode. That'll change
in the next commits.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff 6e77137b Sat May 02 11:37:52 MDT 2015 Al Viro <viro@zeniv.linux.org.uk> don't pass nameidata to ->follow_link()

its only use is getting passed to nd_jump_link(), which can obtain
it from current->nameidata

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
H A Dxfs_itable.cdiff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6e57c542 Thu Nov 06 14:31:13 MST 2014 Dave Chinner <dchinner@redhat.com> xfs: bulkstat main loop logic is a mess

There are a bunch of variables tha tare more wildy scoped than they
need to be, obfuscated user buffer checks and tortured "next inode"
tracking. This all needs cleaning up to expose the real issues that
need fixing.

cc: <stable@vger.kernel.org> # 3.17
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6a7f422d Tue Apr 22 01:33:40 MDT 2008 Christoph Hellwig <hch@infradead.org> [XFS] kill di_mode checks after xfs_iget

Unless XFS_IGET_CREATE is passed xfs_iget will return ENOENT if it
encounters an inode with di_mode == 0. Remove the duplicated checks in the
callers.

(the log recovery case is not touched for now)

SGI-PV: 976035
SGI-Modid: xfs-linux-melb:xfs-kern:30898a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff 6e73b418 Wed Sep 27 19:06:21 MDT 2006 Vlad Apostolov <vapo@sgi.com> [XFS] 955947: Infinite loop in xfs_bulkstat() on formatter() error

SGI-PV: 955947
SGI-Modid: xfs-linux-melb:xfs-kern:26986a

Signed-off-by: Vlad Apostolov <vapo@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
diff 6f1f2168 Wed Sep 27 19:06:15 MDT 2006 Vlad Apostolov <vapo@sgi.com> [XFS] pv 956241, author: nathans, rv: vapo - make ino validation checks
consistent in bulkstat

SGI-PV: 956241
SGI-Modid: xfs-linux-melb:xfs-kern:26984a

Signed-off-by: Vlad Apostolov <vapo@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
H A Dxfs_qm.cdiff 0a97c01c Thu Nov 30 12:40:18 MST 2023 Nhat Pham <nphamcs@gmail.com> list_lru: allow explicit memcg and NUMA node selection

Patch series "workload-specific and memory pressure-driven zswap
writeback", v8.

There are currently several issues with zswap writeback:

1. There is only a single global LRU for zswap, making it impossible to
perform worload-specific shrinking - an memcg under memory pressure
cannot determine which pages in the pool it owns, and often ends up
writing pages from other memcgs. This issue has been previously
observed in practice and mitigated by simply disabling
memcg-initiated shrinking:

https://lore.kernel.org/all/20230530232435.3097106-1-nphamcs@gmail.com/T/#u

But this solution leaves a lot to be desired, as we still do not
have an avenue for an memcg to free up its own memory locked up in
the zswap pool.

2. We only shrink the zswap pool when the user-defined limit is hit.
This means that if we set the limit too high, cold data that are
unlikely to be used again will reside in the pool, wasting precious
memory. It is hard to predict how much zswap space will be needed
ahead of time, as this depends on the workload (specifically, on
factors such as memory access patterns and compressibility of the
memory pages).

This patch series solves these issues by separating the global zswap LRU
into per-memcg and per-NUMA LRUs, and performs workload-specific (i.e
memcg- and NUMA-aware) zswap writeback under memory pressure. The new
shrinker does not have any parameter that must be tuned by the user, and
can be opted in or out on a per-memcg basis.

As a proof of concept, we ran the following synthetic benchmark: build the
linux kernel in a memory-limited cgroup, and allocate some cold data in
tmpfs to see if the shrinker could write them out and improved the overall
performance. Depending on the amount of cold data generated, we observe
from 14% to 35% reduction in kernel CPU time used in the kernel builds.


This patch (of 6):

The interface of list_lru is based on the assumption that the list node
and the data it represents belong to the same allocated on the correct
node/memcg. While this assumption is valid for existing slab objects LRU
such as dentries and inodes, it is undocumented, and rather inflexible for
certain potential list_lru users (such as the upcoming zswap shrinker and
the THP shrinker). It has caused us a lot of issues during our
development.

This patch changes list_lru interface so that the caller must explicitly
specify numa node and memcg when adding and removing objects. The old
list_lru_add() and list_lru_del() are renamed to list_lru_add_obj() and
list_lru_del_obj(), respectively.

It also extends the list_lru API with a new function, list_lru_putback,
which undoes a previous list_lru_isolate call. Unlike list_lru_add, it
does not increment the LRU node count (as list_lru_isolate does not
decrement the node count). list_lru_putback also allows for explicit
memcg and NUMA node selection.

Link: https://lkml.kernel.org/r/20231130194023.4102148-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20231130194023.4102148-2-nphamcs@gmail.com
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff e33c267a Tue May 31 21:22:24 MDT 2022 Roman Gushchin <roman.gushchin@linux.dev> mm: shrinkers: provide shrinkers with names

Currently shrinkers are anonymous objects. For debugging purposes they
can be identified by count/scan function names, but it's not always
useful: e.g. for superblock's shrinkers it's nice to have at least an
idea of to which superblock the shrinker belongs.

This commit adds names to shrinkers. register_shrinker() and
prealloc_shrinker() functions are extended to take a format and arguments
to master a name.

In some cases it's not possible to determine a good name at the time when
a shrinker is allocated. For such cases shrinker_debugfs_rename() is
provided.

The expected format is:
<subsystem>-<shrinker_type>[:<instance>]-<id>
For some shrinkers an instance can be encoded as (MAJOR:MINOR) pair.

After this change the shrinker debugfs directory looks like:
$ cd /sys/kernel/debug/shrinker/
$ ls
dquota-cache-16 sb-devpts-28 sb-proc-47 sb-tmpfs-42
mm-shadow-18 sb-devtmpfs-5 sb-proc-48 sb-tmpfs-43
mm-zspool:zram0-34 sb-hugetlbfs-17 sb-pstore-31 sb-tmpfs-44
rcu-kfree-0 sb-hugetlbfs-33 sb-rootfs-2 sb-tmpfs-49
sb-aio-20 sb-iomem-12 sb-securityfs-6 sb-tracefs-13
sb-anon_inodefs-15 sb-mqueue-21 sb-selinuxfs-22 sb-xfs:vda1-36
sb-bdev-3 sb-nsfs-4 sb-sockfs-8 sb-zsmalloc-19
sb-bpf-32 sb-pipefs-14 sb-sysfs-26 thp-deferred_split-10
sb-btrfs:vda2-24 sb-proc-25 sb-tmpfs-1 thp-zero-9
sb-cgroup2-30 sb-proc-39 sb-tmpfs-27 xfs-buf:vda1-37
sb-configfs-23 sb-proc-41 sb-tmpfs-29 xfs-inodegc:vda1-38
sb-dax-11 sb-proc-45 sb-tmpfs-35
sb-debugfs-7 sb-proc-46 sb-tmpfs-40

[roman.gushchin@linux.dev: fix build warnings]
Link: https://lkml.kernel.org/r/Yr+ZTnLb9lJk6fJO@castle
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lkml.kernel.org/r/20220601032227.4076670-4-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff 86d40f1e Thu May 26 18:21:43 MDT 2022 Darrick J. Wong <djwong@kernel.org> xfs: purge dquots after inode walk fails during quotacheck

xfs/434 and xfs/436 have been reporting occasional memory leaks of
xfs_dquot objects. These tests themselves were the messenger, not the
culprit, since they unload the xfs module, which trips the slub
debugging code while tearing down all the xfs slab caches:

=============================================================================
BUG xfs_dquot (Tainted: G W ): Objects remaining in xfs_dquot on __kmem_cache_shutdown()
-----------------------------------------------------------------------------

Slab 0xffffea000606de00 objects=30 used=5 fp=0xffff888181b78a78 flags=0x17ff80000010200(slab|head|node=0|zone=2|lastcpupid=0xfff)
CPU: 0 PID: 3953166 Comm: modprobe Tainted: G W 5.18.0-rc6-djwx #rc6 d5824be9e46a2393677bda868f9b154d917ca6a7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20171121_152543-x86-ol7-builder-01.us.oracle.com-4.el7.1 04/01/2014

Since we don't generally rmmod the xfs module between fstests, this
means that xfs/434 is really just the canary in the coal mine --
something leaked a dquot, but we don't know who. After days of pounding
on fstests with kmemleak enabled, I finally got it to spit this out:

unreferenced object 0xffff8880465654c0 (size 536):
comm "u10:4", pid 88, jiffies 4294935810 (age 29.512s)
hex dump (first 32 bytes):
60 4a 56 46 80 88 ff ff 58 ea e4 5c 80 88 ff ff `JVF....X..\....
00 e0 52 49 80 88 ff ff 01 00 01 00 00 00 00 00 ..RI............
backtrace:
[<ffffffffa0740f6c>] xfs_dquot_alloc+0x2c/0x530 [xfs]
[<ffffffffa07443df>] xfs_qm_dqread+0x6f/0x330 [xfs]
[<ffffffffa07462a2>] xfs_qm_dqget+0x132/0x4e0 [xfs]
[<ffffffffa0756bb0>] xfs_qm_quotacheck_dqadjust+0xa0/0x3e0 [xfs]
[<ffffffffa075724d>] xfs_qm_dqusage_adjust+0x35d/0x4f0 [xfs]
[<ffffffffa06c9068>] xfs_iwalk_ag_recs+0x348/0x5d0 [xfs]
[<ffffffffa06c95d3>] xfs_iwalk_run_callbacks+0x273/0x540 [xfs]
[<ffffffffa06c9e8d>] xfs_iwalk_ag+0x5ed/0x890 [xfs]
[<ffffffffa06ca22f>] xfs_iwalk_ag_work+0xff/0x170 [xfs]
[<ffffffffa06d22c9>] xfs_pwork_work+0x79/0x130 [xfs]
[<ffffffff81170bb2>] process_one_work+0x672/0x1040
[<ffffffff81171b1b>] worker_thread+0x59b/0xec0
[<ffffffff8118711e>] kthread+0x29e/0x340
[<ffffffff810032bf>] ret_from_fork+0x1f/0x30

Now we know that quotacheck is at fault, but even this report was
canaryish -- it was triggered by xfs/494, which doesn't actually mount
any filesystems. (kmemleak can be a little slow to notice leaks, even
with fstests repeatedly whacking it to look for them.) Looking at the
*previous* fstest, however, showed that the test run before xfs/494 was
xfs/117. The tipoff to the problem is in this excerpt from dmesg:

XFS (sda4): Quotacheck needed: Please wait.
XFS (sda4): Metadata corruption detected at xfs_dinode_verify.part.0+0xdb/0x7b0 [xfs], inode 0x119 dinode
XFS (sda4): Unmount and run xfs_repair
XFS (sda4): First 128 bytes of corrupted metadata buffer:
00000000: 49 4e 81 a4 03 02 00 00 00 00 00 00 00 00 00 00 IN..............
00000010: 00 00 00 01 00 00 00 00 00 90 57 54 54 1a 4c 68 ..........WTT.Lh
00000020: 81 f9 7d e1 6d ee 16 00 34 bd 7d e1 6d ee 16 00 ..}.m...4.}.m...
00000030: 34 bd 7d e1 6d ee 16 00 00 00 00 00 00 00 00 00 4.}.m...........
00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000050: 00 00 00 02 00 00 00 00 00 00 00 00 96 80 f3 ab ................
00000060: ff ff ff ff da 57 7b 11 00 00 00 00 00 00 00 03 .....W{.........
00000070: 00 00 00 01 00 00 00 10 00 00 00 00 00 00 00 08 ................
XFS (sda4): Quotacheck: Unsuccessful (Error -117): Disabling quotas.

The dinode verifier decided that the inode was corrupt, which causes
iget to return with EFSCORRUPTED. Since this happened during
quotacheck, it is obvious that the kernel aborted the inode walk on
account of the corruption error and disabled quotas. Unfortunately, we
neglect to purge the dquot cache before doing that, which is how the
dquots leaked.

The problems started 10 years ago in commit b84a3a, when the dquot lists
were converted to a radix tree, but the error handling behavior was not
correctly preserved -- in that commit, if the bulkstat failed and
usrquota was enabled, the bulkstat failure code would be overwritten by
the result of flushing all the dquots to disk. As long as that
succeeds, we'd continue the quota mount as if everything were ok, but
instead we're now operating with a corrupt inode and incorrect quota
usage counts. I didn't notice this bug in 2019 when I wrote commit
ebd126a, which changed quotacheck to skip the dqflush when the scan
doesn't complete due to inode walk failures.

Introduced-by: b84a3a96751f ("xfs: remove the per-filesystem list of dquots")
Fixes: ebd126a651f8 ("xfs: convert quotacheck to use the new iwalk functions")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 86d40f1e Thu May 26 18:21:43 MDT 2022 Darrick J. Wong <djwong@kernel.org> xfs: purge dquots after inode walk fails during quotacheck

xfs/434 and xfs/436 have been reporting occasional memory leaks of
xfs_dquot objects. These tests themselves were the messenger, not the
culprit, since they unload the xfs module, which trips the slub
debugging code while tearing down all the xfs slab caches:

=============================================================================
BUG xfs_dquot (Tainted: G W ): Objects remaining in xfs_dquot on __kmem_cache_shutdown()
-----------------------------------------------------------------------------

Slab 0xffffea000606de00 objects=30 used=5 fp=0xffff888181b78a78 flags=0x17ff80000010200(slab|head|node=0|zone=2|lastcpupid=0xfff)
CPU: 0 PID: 3953166 Comm: modprobe Tainted: G W 5.18.0-rc6-djwx #rc6 d5824be9e46a2393677bda868f9b154d917ca6a7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20171121_152543-x86-ol7-builder-01.us.oracle.com-4.el7.1 04/01/2014

Since we don't generally rmmod the xfs module between fstests, this
means that xfs/434 is really just the canary in the coal mine --
something leaked a dquot, but we don't know who. After days of pounding
on fstests with kmemleak enabled, I finally got it to spit this out:

unreferenced object 0xffff8880465654c0 (size 536):
comm "u10:4", pid 88, jiffies 4294935810 (age 29.512s)
hex dump (first 32 bytes):
60 4a 56 46 80 88 ff ff 58 ea e4 5c 80 88 ff ff `JVF....X..\....
00 e0 52 49 80 88 ff ff 01 00 01 00 00 00 00 00 ..RI............
backtrace:
[<ffffffffa0740f6c>] xfs_dquot_alloc+0x2c/0x530 [xfs]
[<ffffffffa07443df>] xfs_qm_dqread+0x6f/0x330 [xfs]
[<ffffffffa07462a2>] xfs_qm_dqget+0x132/0x4e0 [xfs]
[<ffffffffa0756bb0>] xfs_qm_quotacheck_dqadjust+0xa0/0x3e0 [xfs]
[<ffffffffa075724d>] xfs_qm_dqusage_adjust+0x35d/0x4f0 [xfs]
[<ffffffffa06c9068>] xfs_iwalk_ag_recs+0x348/0x5d0 [xfs]
[<ffffffffa06c95d3>] xfs_iwalk_run_callbacks+0x273/0x540 [xfs]
[<ffffffffa06c9e8d>] xfs_iwalk_ag+0x5ed/0x890 [xfs]
[<ffffffffa06ca22f>] xfs_iwalk_ag_work+0xff/0x170 [xfs]
[<ffffffffa06d22c9>] xfs_pwork_work+0x79/0x130 [xfs]
[<ffffffff81170bb2>] process_one_work+0x672/0x1040
[<ffffffff81171b1b>] worker_thread+0x59b/0xec0
[<ffffffff8118711e>] kthread+0x29e/0x340
[<ffffffff810032bf>] ret_from_fork+0x1f/0x30

Now we know that quotacheck is at fault, but even this report was
canaryish -- it was triggered by xfs/494, which doesn't actually mount
any filesystems. (kmemleak can be a little slow to notice leaks, even
with fstests repeatedly whacking it to look for them.) Looking at the
*previous* fstest, however, showed that the test run before xfs/494 was
xfs/117. The tipoff to the problem is in this excerpt from dmesg:

XFS (sda4): Quotacheck needed: Please wait.
XFS (sda4): Metadata corruption detected at xfs_dinode_verify.part.0+0xdb/0x7b0 [xfs], inode 0x119 dinode
XFS (sda4): Unmount and run xfs_repair
XFS (sda4): First 128 bytes of corrupted metadata buffer:
00000000: 49 4e 81 a4 03 02 00 00 00 00 00 00 00 00 00 00 IN..............
00000010: 00 00 00 01 00 00 00 00 00 90 57 54 54 1a 4c 68 ..........WTT.Lh
00000020: 81 f9 7d e1 6d ee 16 00 34 bd 7d e1 6d ee 16 00 ..}.m...4.}.m...
00000030: 34 bd 7d e1 6d ee 16 00 00 00 00 00 00 00 00 00 4.}.m...........
00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000050: 00 00 00 02 00 00 00 00 00 00 00 00 96 80 f3 ab ................
00000060: ff ff ff ff da 57 7b 11 00 00 00 00 00 00 00 03 .....W{.........
00000070: 00 00 00 01 00 00 00 10 00 00 00 00 00 00 00 08 ................
XFS (sda4): Quotacheck: Unsuccessful (Error -117): Disabling quotas.

The dinode verifier decided that the inode was corrupt, which causes
iget to return with EFSCORRUPTED. Since this happened during
quotacheck, it is obvious that the kernel aborted the inode walk on
account of the corruption error and disabled quotas. Unfortunately, we
neglect to purge the dquot cache before doing that, which is how the
dquots leaked.

The problems started 10 years ago in commit b84a3a, when the dquot lists
were converted to a radix tree, but the error handling behavior was not
correctly preserved -- in that commit, if the bulkstat failed and
usrquota was enabled, the bulkstat failure code would be overwritten by
the result of flushing all the dquots to disk. As long as that
succeeds, we'd continue the quota mount as if everything were ok, but
instead we're now operating with a corrupt inode and incorrect quota
usage counts. I didn't notice this bug in 2019 when I wrote commit
ebd126a, which changed quotacheck to skip the dqflush when the scan
doesn't complete due to inode walk failures.

Introduced-by: b84a3a96751f ("xfs: remove the per-filesystem list of dquots")
Fixes: ebd126a651f8 ("xfs: convert quotacheck to use the new iwalk functions")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 86d40f1e Thu May 26 18:21:43 MDT 2022 Darrick J. Wong <djwong@kernel.org> xfs: purge dquots after inode walk fails during quotacheck

xfs/434 and xfs/436 have been reporting occasional memory leaks of
xfs_dquot objects. These tests themselves were the messenger, not the
culprit, since they unload the xfs module, which trips the slub
debugging code while tearing down all the xfs slab caches:

=============================================================================
BUG xfs_dquot (Tainted: G W ): Objects remaining in xfs_dquot on __kmem_cache_shutdown()
-----------------------------------------------------------------------------

Slab 0xffffea000606de00 objects=30 used=5 fp=0xffff888181b78a78 flags=0x17ff80000010200(slab|head|node=0|zone=2|lastcpupid=0xfff)
CPU: 0 PID: 3953166 Comm: modprobe Tainted: G W 5.18.0-rc6-djwx #rc6 d5824be9e46a2393677bda868f9b154d917ca6a7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20171121_152543-x86-ol7-builder-01.us.oracle.com-4.el7.1 04/01/2014

Since we don't generally rmmod the xfs module between fstests, this
means that xfs/434 is really just the canary in the coal mine --
something leaked a dquot, but we don't know who. After days of pounding
on fstests with kmemleak enabled, I finally got it to spit this out:

unreferenced object 0xffff8880465654c0 (size 536):
comm "u10:4", pid 88, jiffies 4294935810 (age 29.512s)
hex dump (first 32 bytes):
60 4a 56 46 80 88 ff ff 58 ea e4 5c 80 88 ff ff `JVF....X..\....
00 e0 52 49 80 88 ff ff 01 00 01 00 00 00 00 00 ..RI............
backtrace:
[<ffffffffa0740f6c>] xfs_dquot_alloc+0x2c/0x530 [xfs]
[<ffffffffa07443df>] xfs_qm_dqread+0x6f/0x330 [xfs]
[<ffffffffa07462a2>] xfs_qm_dqget+0x132/0x4e0 [xfs]
[<ffffffffa0756bb0>] xfs_qm_quotacheck_dqadjust+0xa0/0x3e0 [xfs]
[<ffffffffa075724d>] xfs_qm_dqusage_adjust+0x35d/0x4f0 [xfs]
[<ffffffffa06c9068>] xfs_iwalk_ag_recs+0x348/0x5d0 [xfs]
[<ffffffffa06c95d3>] xfs_iwalk_run_callbacks+0x273/0x540 [xfs]
[<ffffffffa06c9e8d>] xfs_iwalk_ag+0x5ed/0x890 [xfs]
[<ffffffffa06ca22f>] xfs_iwalk_ag_work+0xff/0x170 [xfs]
[<ffffffffa06d22c9>] xfs_pwork_work+0x79/0x130 [xfs]
[<ffffffff81170bb2>] process_one_work+0x672/0x1040
[<ffffffff81171b1b>] worker_thread+0x59b/0xec0
[<ffffffff8118711e>] kthread+0x29e/0x340
[<ffffffff810032bf>] ret_from_fork+0x1f/0x30

Now we know that quotacheck is at fault, but even this report was
canaryish -- it was triggered by xfs/494, which doesn't actually mount
any filesystems. (kmemleak can be a little slow to notice leaks, even
with fstests repeatedly whacking it to look for them.) Looking at the
*previous* fstest, however, showed that the test run before xfs/494 was
xfs/117. The tipoff to the problem is in this excerpt from dmesg:

XFS (sda4): Quotacheck needed: Please wait.
XFS (sda4): Metadata corruption detected at xfs_dinode_verify.part.0+0xdb/0x7b0 [xfs], inode 0x119 dinode
XFS (sda4): Unmount and run xfs_repair
XFS (sda4): First 128 bytes of corrupted metadata buffer:
00000000: 49 4e 81 a4 03 02 00 00 00 00 00 00 00 00 00 00 IN..............
00000010: 00 00 00 01 00 00 00 00 00 90 57 54 54 1a 4c 68 ..........WTT.Lh
00000020: 81 f9 7d e1 6d ee 16 00 34 bd 7d e1 6d ee 16 00 ..}.m...4.}.m...
00000030: 34 bd 7d e1 6d ee 16 00 00 00 00 00 00 00 00 00 4.}.m...........
00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000050: 00 00 00 02 00 00 00 00 00 00 00 00 96 80 f3 ab ................
00000060: ff ff ff ff da 57 7b 11 00 00 00 00 00 00 00 03 .....W{.........
00000070: 00 00 00 01 00 00 00 10 00 00 00 00 00 00 00 08 ................
XFS (sda4): Quotacheck: Unsuccessful (Error -117): Disabling quotas.

The dinode verifier decided that the inode was corrupt, which causes
iget to return with EFSCORRUPTED. Since this happened during
quotacheck, it is obvious that the kernel aborted the inode walk on
account of the corruption error and disabled quotas. Unfortunately, we
neglect to purge the dquot cache before doing that, which is how the
dquots leaked.

The problems started 10 years ago in commit b84a3a, when the dquot lists
were converted to a radix tree, but the error handling behavior was not
correctly preserved -- in that commit, if the bulkstat failed and
usrquota was enabled, the bulkstat failure code would be overwritten by
the result of flushing all the dquots to disk. As long as that
succeeds, we'd continue the quota mount as if everything were ok, but
instead we're now operating with a corrupt inode and incorrect quota
usage counts. I didn't notice this bug in 2019 when I wrote commit
ebd126a, which changed quotacheck to skip the dqflush when the scan
doesn't complete due to inode walk failures.

Introduced-by: b84a3a96751f ("xfs: remove the per-filesystem list of dquots")
Fixes: ebd126a651f8 ("xfs: convert quotacheck to use the new iwalk functions")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6d3ebaae Thu Nov 27 20:24:06 MST 2014 Christoph Hellwig <hch@lst.de> xfs: merge xfs_dinode.h into xfs_format.h

More consolidatation for the on-disk format defintions. Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6ea94bb5 Mon Apr 14 03:03:34 MDT 2014 Eric Sandeen <sandeen@redhat.com> xfs: remove unused mp arg from xfs_calc_dquots_per_chunk()

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff 6ca1c906 Mon Aug 12 04:49:26 MDT 2013 Dave Chinner <dchinner@redhat.com> xfs: separate dquot on disk format definitions out of xfs_quota.h

The on disk format definitions of the on-disk dquot, log formats and
quota off log formats are all intertwined with other definitions for
quotas. Separate them out into their own header file so they can
easily be shared with userspace.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
H A Dxfs_quotaops.cdiff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6ca1c906 Mon Aug 12 04:49:26 MDT 2013 Dave Chinner <dchinner@redhat.com> xfs: separate dquot on disk format definitions out of xfs_quota.h

The on disk format definitions of the on-disk dquot, log formats and
quota off log formats are all intertwined with other definitions for
quotas. Separate them out into their own header file so they can
easily be shared with userspace.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
H A Dxfs_trans.cdiff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff 6e73a545 Mon Mar 29 12:11:40 MDT 2021 Christoph Hellwig <hch@lst.de> 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>
diff b41b46c2 Wed May 20 14:17:11 MDT 2020 Dave Chinner <dchinner@redhat.com> xfs: remove the m_active_trans counter

It's a global atomic counter, and we are hitting it at a rate of
half a million transactions a second, so it's bouncing the counter
cacheline all over the place on large machines. We don't actually
need it anymore - it used to be required because the VFS freeze code
could not track/prevent filesystem transactions that were running,
but that problem no longer exists.

Hence to remove the counter, we simply have to ensure that nothing
calls xfs_sync_sb() while we are trying to quiesce the filesytem.
That only happens if the log worker is still running when we call
xfs_quiesce_attr(). The log worker is cancelled at the end of
xfs_quiesce_attr() by calling xfs_log_quiesce(), so just call it
early here and then we can remove the counter altogether.

Concurrent create, 50 million inodes, identical 16p/16GB virtual
machines on different physical hosts. Machine A has twice the CPU
cores per socket of machine B:

unpatched patched
machine A: 3m16s 2m00s
machine B: 4m04s 4m05s

Create rates:
unpatched patched
machine A: 282k+/-31k 468k+/-21k
machine B: 231k+/-8k 233k+/-11k

Concurrent rm of same 50 million inodes:

unpatched patched
machine A: 6m42s 2m33s
machine B: 4m47s 4m47s

The transaction rate on the fast machine went from just under
300k/sec to 700k/sec, which indicates just how much of a bottleneck
this atomic counter was.

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>
diff 6aa67184 Wed Jul 11 23:26:07 MDT 2018 Brian Foster <bfoster@redhat.com> xfs: rename xfs_trans ->t_agfl_dfops to ->t_dfops

The ->t_agfl_dfops field is currently used to defer agfl block frees
from associated transaction contexts. While all known problematic
contexts have already been updated to use ->t_agfl_dfops, the
broader goal is defer agfl frees from all callers that already use a
deferred operations structure. Further, the transaction field
facilitates a good amount of code clean up where the transaction and
dfops have historically been passed down through the stack
separately.

Rename the field to something more generic to prepare to use it as
such throughout XFS. This patch does not change behavior.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
diff 6ca1c906 Mon Aug 12 04:49:26 MDT 2013 Dave Chinner <dchinner@redhat.com> xfs: separate dquot on disk format definitions out of xfs_quota.h

The on disk format definitions of the on-disk dquot, log formats and
quota off log formats are all intertwined with other definitions for
quotas. Separate them out into their own header file so they can
easily be shared with userspace.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

Completed in 1875 milliseconds