Consolidate mark_superblock() and trans_mark_superblock(), like we did
with the other trigger paths.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This optimization reduces the average number of comparisons required
from 2*n*log2(n) - 3*n + o(n) to n*log2(n) + 0.37*n + o(n). When n is
sufficiently large, it results in approximately 50% fewer comparisons.
Currently, eytzinger0_sort employs the textbook version of heapsort,
where during the heapify process, each level requires two comparisons
to determine the maximum among three elements. In contrast, the
bottom-up heapsort, during heapify, only compares two children at each
level until reaching a leaf node. Then, it backtracks from the leaf
node to find the correct position. Since heapify typically continues
until very close to the leaf node, the standard heapify requires about
2*log2(n) comparisons, while the bottom-up variant only needs log2(n)
comparisons.
The experimental data presented below is based on an array generated
by get_random_u32().
| N | comparisons(old) | comparisons(new) | time(old) | time(new) |
|-------|------------------|------------------|-----------|-----------|
| 10000 | 235381 | 136615 | 25545 us | 20366 us |
| 20000 | 510694 | 293425 | 31336 us | 18312 us |
| 30000 | 800384 | 457412 | 35042 us | 27386 us |
| 40000 | 1101617 | 626831 | 48779 us | 38253 us |
| 50000 | 1409762 | 799637 | 62238 us | 46950 us |
| 60000 | 1721191 | 974521 | 75588 us | 58367 us |
| 70000 | 2038536 | 1152171 | 90823 us | 68778 us |
| 80000 | 2362958 | 1333472 | 104165 us | 78625 us |
| 90000 | 2690900 | 1516065 | 116111 us | 89573 us |
| 100000| 3019413 | 1699879 | 133638 us | 100998 us |
Refs:
BOTTOM-UP-HEAPSORT, a new variant of HEAPSORT beating, on an average,
QUICKSORT (if n is not very small)
Ingo Wegener
Theoretical Computer Science, 118(1); Pages 81-98, 13 September 1993
https://doi.org/10.1016/0304-3975(93)90364-Y
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
reading the journal can take a decent amount of time compared to the
rest of fsck, let's only read it when required.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
- fix assorted (harmless) off-by-one errors
- we were inconsistent on whether out->pos stays <= out->size on
overflow; now it does, and printbuf.overflow exists to indicate if a
printbuf has overflowed
- factor out printbuf_advance_pos()
- printbuf_nul_terminate_reserved(); use this to reduce the number of
printbuf_make_room() calls
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When a superblock write is silently dropped or it's been modified by
another process we need to know which device it was.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Fix another shift-by-64 by factoring out a common helper for
bch2_bkey_format_invalid() and bformat_needs_redo() (where it was
already fixed).
Reported-by: syzbot+9833a1d29d4a44361e2c@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Btree nodes are log structured; thus, we need to emit whiteouts when
we're deleting a key that's been written out to disk.
k->needs_whiteout tracks whether a key will need a whiteout when it's
deleted, and this requires some careful handling; e.g. the key we're
deleting may not have been written out to disk, but it may have
overwritten a key that was - thus we need to carry this flag around on
overwrites.
Invariants:
There may be multiple key for the same position in a given node (because
of overwrites), but only one of them will be a live (non deleted) key,
and only one key for a given position will have the needs_whiteout flag
set.
Additionally, we don't want to carry around whiteouts that need to be
written in the main searchable part of a btree node - btree_iter_peek()
will have to skip past them, and this can lead to an O(n^2) issues when
doing sequential deletions (e.g. inode rm/truncate). So there's a
separate region in the btree node buffer for unwritten whiteouts; these
are merge sorted with the rest of the keys we're writing in the btree
node write path.
The unwritten whiteouts was a later optimization that bch2_sort_keys()
didn't take into account; the unwritten whiteouts area means that we
never have deleted keys with needs_whiteout set in the main searchable
part of a btree node.
That means we can simplify and optimize some sort paths, and eliminate
an assertion that syzbot found:
- Unless we're in the btree node write path, it's always ok to drop
whiteouts when sorting
- When sorting for a btree node write, we drop the whiteout if it's not
from the unwritten whiteouts area, or if it's overwritten by a real
key at the same position.
This completely eliminates some tricky logic for propagating the
needs_whiteout flag: syzbot was able to hit the assertion that checked
that there shouldn't be more than one key at the same pos with
needs_whiteout set, likely due to a combination of flipping on
needs_whiteout on all written keys (they need whiteouts if overwritten),
combined with not always dropping unneeded whiteouts, and the tricky
logic in the sort path for preserving needs_whiteout that wasn't really
needed.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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Merge tag '6.9-rc7-ksmbd-fixes' of git://git.samba.org/ksmbd
Pull smb server fixes from Steve French:
"Five ksmbd server fixes, all also for stable
- Three fixes related to SMB3 leases (fixes two xfstests, and a
locking issue)
- Unitialized variable fix
- Socket creation fix when bindv6only is set"
* tag '6.9-rc7-ksmbd-fixes' of git://git.samba.org/ksmbd:
ksmbd: do not grant v2 lease if parent lease key and epoch are not set
ksmbd: use rwsem instead of rwlock for lease break
ksmbd: avoid to send duplicate lease break notifications
ksmbd: off ipv6only for both ipv4/ipv6 binding
ksmbd: fix uninitialized symbol 'share' in smb2_tree_connect()
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Merge tag 'fuse-fixes-6.9-final' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
"Two one-liner fixes for issues introduced in -rc1"
* tag 'fuse-fixes-6.9-final' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
virtiofs: include a newline in sysfs tag
fuse: verify zero padding in fuse_backing_map
- Fix xfstests generic/013 test failure with dirsync mount option.
- Initialize the reserved fields of deleted file and stream extension
dentries to zero.
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Merge tag 'exfat-for-6.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat
Pull exfat fixes from Namjae Jeon:
- Fix xfstests generic/013 test failure with dirsync mount option
- Initialize the reserved fields of deleted file and stream extension
dentries to zero
* tag 'exfat-for-6.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
exfat: zero the reserved fields of file and stream extension dentries
exfat: fix timing of synchronizing bitmap and inode
Merely checking if the directory is encrypted happens for every open
when using ext4, at the moment refing and unrefing the parent, costing 2
atomics and serializing opens of different files.
The most common case of encryption not being used can be checked for
with RCU instead.
Sample result from open1_processes -t 20 ("Separate file open/close")
from will-it-scale on Sapphire Rapids (ops/s):
before: 12539898
after: 25575494 (+103%)
v2:
- add a comment justifying rcu usage, submitted by Eric Biggers
- whack spurious IS_ENCRYPTED check from the refed case
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20240508081400.422212-1-mjguzik@gmail.com
Signed-off-by: Eric Biggers <ebiggers@google.com>
- Various syzbot fixes; mainly small gaps in validation
- Fix an integer overflow in fiemap() which was preventing filefrag from
returning the full list of extents
- Fix a refcounting bug on the device refcount, turned up by new
assertions in the development branch
- Fix a device removal/readd bug; write_super() was repeatedly dropping
and retaking bch_dev->io_ref references
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Merge tag 'bcachefs-2024-05-07.2' of https://evilpiepirate.org/git/bcachefs
Pull bcachefs fixes from Kent Overstreet:
- Various syzbot fixes; mainly small gaps in validation
- Fix an integer overflow in fiemap() which was preventing filefrag
from returning the full list of extents
- Fix a refcounting bug on the device refcount, turned up by new
assertions in the development branch
- Fix a device removal/readd bug; write_super() was repeatedly dropping
and retaking bch_dev->io_ref references
* tag 'bcachefs-2024-05-07.2' of https://evilpiepirate.org/git/bcachefs:
bcachefs: Add missing sched_annotate_sleep() in bch2_journal_flush_seq_async()
bcachefs: Fix race in bch2_write_super()
bcachefs: BCH_SB_LAYOUT_SIZE_BITS_MAX
bcachefs: Add missing skcipher_request_set_callback() call
bcachefs: Fix snapshot_t() usage in bch2_fs_quota_read_inode()
bcachefs: Fix shift-by-64 in bformat_needs_redo()
bcachefs: Guard against unknown k.k->type in __bkey_invalid()
bcachefs: Add missing validation for superblock section clean
bcachefs: Fix assert in bch2_alloc_v4_invalid()
bcachefs: fix overflow in fiemap
bcachefs: Add a better limit for maximum number of buckets
bcachefs: Fix lifetime issue in device iterator helpers
bcachefs: Fix bch2_dev_lookup() refcounting
bcachefs: Initialize bch_write_op->failed in inline data path
bcachefs: Fix refcount put in sb_field_resize error path
bcachefs: Inodes need extra padding for varint_decode_fast()
bcachefs: Fix early error path in bch2_fs_btree_key_cache_exit()
bcachefs: bucket_pos_to_bp_noerror()
bcachefs: don't free error pointers
bcachefs: Fix a scheduler splat in __bch2_next_write_buffer_flush_journal_buf()
Introduce the capability to dynamically configure the maximum file
note size for ELF core dumps via sysctl.
Why is this being done?
We have observed that during a crash when there are more than 65k mmaps
in memory, the existing fixed limit on the size of the ELF notes section
becomes a bottleneck. The notes section quickly reaches its capacity,
leading to incomplete memory segment information in the resulting coredump.
This truncation compromises the utility of the coredumps, as crucial
information about the memory state at the time of the crash might be
omitted.
This enhancement removes the previous static limit of 4MB, allowing
system administrators to adjust the size based on system-specific
requirements or constraints.
Eg:
$ sysctl -a | grep core_file_note_size_limit
kernel.core_file_note_size_limit = 4194304
$ sysctl -n kernel.core_file_note_size_limit
4194304
$echo 519304 > /proc/sys/kernel/core_file_note_size_limit
$sysctl -n kernel.core_file_note_size_limit
519304
Attempting to write beyond the ceiling value of 16MB
$echo 17194304 > /proc/sys/kernel/core_file_note_size_limit
bash: echo: write error: Invalid argument
Signed-off-by: Vijay Nag <nagvijay@microsoft.com>
Signed-off-by: Allen Pais <apais@linux.microsoft.com>
Link: https://lore.kernel.org/r/20240506193700.7884-1-apais@linux.microsoft.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Upon running sparse, "warning: dubious: x & !y" is output at an array
index calculation within nilfs_load_super_block().
The calculation is not wrong, but to eliminate the sparse warning, replace
it with an equivalent calculation.
Also, add a comment to make it easier to understand what the unintuitive
array index calculation is doing and whether it's correct.
Link: https://lkml.kernel.org/r/20240430080019.4242-3-konishi.ryusuke@gmail.com
Fixes: e339ad31f5 ("nilfs2: introduce secondary super block")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Nobody checks the error flag on squashfs folios, so stop setting it.
Link: https://lkml.kernel.org/r/20240420025029.2166544-24-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove use of page APIs, return the errno instead of 0, switch from
kmap_atomic to kmap_local and use folio_end_read() to unify the two exit
paths.
Link: https://lkml.kernel.org/r/20240420025029.2166544-23-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Phillip Lougher <phillip@squashfs.org.uk>
Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Variable status is being assigned and error code that is never read, it is
being assigned inside of a do-while loop. The assignment is redundant and
can be removed.
Cleans up clang scan build warning:
fs/ocfs2/dlm/dlmdomain.c:1530:2: warning: Value stored to 'status' is never
read [deadcode.DeadStores]
Link: https://lkml.kernel.org/r/20240423223018.1573213-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the superblock's UUID to generate the fsid when it's non-null.
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240409113022.74720-1-hongzhen@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
This adds a special global buffer pool (in the end) for reserved pages.
Using a reserved pool for LZ4 decompression significantly reduces the
time spent on extra temporary page allocation for the extreme cases in
low memory scenarios.
The table below shows the reduction in time spent on page allocation for
LZ4 decompression when using a reserved pool. The results were obtained
from multi-app launch benchmarks on ARM64 Android devices running the
5.15 kernel with an 8-core CPU and 8GB of memory. In the benchmark, we
launched 16 frequently-used apps, and the camera app was the last one in
each round. The data in the table is the average time of camera app for
each round.
After using the reserved pool, there was an average improvement of 150ms
in the overall launch time of our camera app, which was obtained from
the systrace log.
+--------------+---------------+--------------+---------+
| | w/o page pool | w/ page pool | diff |
+--------------+---------------+--------------+---------+
| Average (ms) | 3434 | 21 | -99.38% |
+--------------+---------------+--------------+---------+
Based on the benchmark logs, 64 pages are sufficient for 95% of
scenarios. This value can be adjusted with a module parameter
`reserved_pages`. The default value is 0.
This pool is currently only used for the LZ4 decompressor, but it can be
applied to more decompressors if needed.
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240402131523.2703948-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Let's use alloc_pages_bulk_array() for simplicity and get rid of
unnecessary pagepool.
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240402092757.2635257-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
It will cost more time if compressed buffers are allocated on demand for
low-latency algorithms (like lz4) so EROFS uses per-CPU buffers to keep
compressed data if in-place decompression is unfulfilled. While it is kind
of wasteful of memory for a device with hundreds of CPUs, and only a small
number of CPUs concurrently decompress most of the time.
This patch renames it as 'global buffer pool' and makes it configurable.
This allows two or more CPUs to share a common buffer to reduce memory
occupation.
Suggested-by: Gao Xiang <xiang@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Link: https://lore.kernel.org/r/20240402100036.2673604-1-guochunhai@vivo.com
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Link: https://lore.kernel.org/r/20240408215231.3376659-1-dhavale@google.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Currently, utils.c is only useful if CONFIG_EROFS_FS_ZIP is on.
So let's rename it to zutil.c as well as avoid its inclusion if
CONFIG_EROFS_FS_ZIP is explicitly disabled.
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240401135550.2550043-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
The internal tag string doesn't contain a newline. Append one when
emitting the tag via sysfs.
[Stefan] Orthogonal to the newline issue, sysfs_emit(buf, "%s", fs->tag) is
needed to prevent format string injection.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Fixes: a8f62f50b4 ("virtiofs: export filesystem tags through sysfs")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
In ext4_xattr_block_cache_find(), when ext4_sb_bread() returns an error,
we will either continue to find the next ea block or return NULL to try to
insert a new ea block. But whether ext4_sb_bread() returns -EIO or -ENOMEM,
the next operation is most likely to fail with the same error. So propagate
the error returned by ext4_sb_bread() to make ext4_xattr_block_set() fail
to reduce pointless operations.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240504075526.2254349-3-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Syzbot reports a warning as follows:
============================================
WARNING: CPU: 0 PID: 5075 at fs/mbcache.c:419 mb_cache_destroy+0x224/0x290
Modules linked in:
CPU: 0 PID: 5075 Comm: syz-executor199 Not tainted 6.9.0-rc6-gb947cc5bf6d7
RIP: 0010:mb_cache_destroy+0x224/0x290 fs/mbcache.c:419
Call Trace:
<TASK>
ext4_put_super+0x6d4/0xcd0 fs/ext4/super.c:1375
generic_shutdown_super+0x136/0x2d0 fs/super.c:641
kill_block_super+0x44/0x90 fs/super.c:1675
ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7327
[...]
============================================
This is because when finding an entry in ext4_xattr_block_cache_find(), if
ext4_sb_bread() returns -ENOMEM, the ce's e_refcnt, which has already grown
in the __entry_find(), won't be put away, and eventually trigger the above
issue in mb_cache_destroy() due to reference count leakage.
So call mb_cache_entry_put() on the -ENOMEM error branch as a quick fix.
Reported-by: syzbot+dd43bd0f7474512edc47@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=dd43bd0f7474512edc47
Fixes: fb265c9cb4 ("ext4: add ext4_sb_bread() to disambiguate ENOMEM cases")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240504075526.2254349-2-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The variable err is being assigned a value that is never read, it
is being re-assigned inside the following while loop and also
after the while loop. The assignment is redundant and can be
removed.
Cleans up clang scan build warning:
fs/jbd2/commit.c:574:2: warning: Value stored to 'err' is never
read [deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240410112803.232993-1-colin.i.king@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
__filemap_get_folio() with FGP_WRITEBEGIN parameter has already wait
for stable folio, so remove the redundant folio_wait_stable() in
ext4_da_write_begin(), it was left over from the commit cc883236b7
("ext4: drop unnecessary journal handle in delalloc write") that
removed the retry getting page logic.
Fixes: cc883236b7 ("ext4: drop unnecessary journal handle in delalloc write")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240419023005.2719050-1-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Smatch complains "err" can be uninitialized in the caller.
fs/ext4/indirect.c:349 ext4_alloc_branch()
error: uninitialized symbol 'err'.
Set the error to zero on the success path.
Fixes: 8016e29f43 ("ext4: fast commit recovery path")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/363a4673-0fb8-4adf-b4fb-90a499077276@moroto.mountain
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
All callers now have a folio, so convert this function from operating on
a page to operating on a folio. The folio is assumed to be a single page.
Signe-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240416172900.244637-4-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There is no need to make this a multi-page folio, so leave all the
infrastructure around it in pages. But since we're locking it, playing
with its refcount and checking whether it's uptodate, it needs to move
to the folio API.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240416172900.244637-3-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There is no need to make this a multi-page folio, so leave all the
infrastructure around it in pages. But since we're locking it, playing
with its refcount and checking whether it's uptodate, it needs to move
to the folio API.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240416172900.244637-2-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The "i++" was accidentally left out so it just sets qgids[0] over and
over.
This can lead to unexpected problems, as the groups[1:] would be all 0,
leading to later find_qgroup_rb() unable to find a qgroup and cause
snapshot creation failure.
Fixes: 5343cd9364 ("btrfs: qgroup: simple quota auto hierarchy for nested subvolumes")
CC: stable@vger.kernel.org # 6.7+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently the error status of super block write is tracked in page/folio
status bit Error. For that we need to keep the reference for the whole
duration of write and wait.
Count the number of superblock writeback errors in the btrfs_device.
That means we don't need the folio to stay around until it's waited for,
and can avoid the extra call to folio_get/put.
Also remove a mention of PageError in a comment as it's the last mention
of the page Error state.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Iterate over folios instead of bvecs. Switch the order of unlock and put
to be the usual order; we know this folio can't be put until it's been
waited for, but that's fragile. Remove the calls to ClearPageUptodate /
SetPageUptodate -- if PAGE_SIZE is larger than BTRFS_SUPER_INFO_SIZE,
we'd be marking the entire folio uptodate without having actually
initialised all the bytes in the page.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a direct conversion from pages to folios, assuming single page
folio. Also removes some calls to obsolete APIs and some hidden calls to
compound_head().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a direct conversion from pages to folios, assuming single page
folio. Also removes a few calls to compound_head() and calls to
obsolete APIs.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have the lock_extent tightly coupled with
extent_clear_unlock_delalloc we can add a cached state to
extent_clear_unlock_delalloc and benefit from skipping the extra lookup
when we're doing cow.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We don't need to include the time we spend in the allocator under our
extent lock protection, move it after the allocator and make sure we
lock the extent in the error case to ensure we're not clearing these
bits without the extent lock held.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we've got the extent lock pushed into cow_file_range() we can
push it further down into the allocation loop. This allows us to only
hold the extent lock during the dropping of the extent map range and
inserting the ordered extent.
This makes the error case a little trickier as we'll now have to lock
the range before clearing any of the other extent bits for the range,
but this is the error path so is less performance critical.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These checks aren't reliant on the extent lock. Move this up into
cow_file_range_inline(), and then update encoded writes to call this
check before calling __cow_file_range_inline(). This will allow us to
skip the extent lock if we're not able to inline the given extent.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we've pushed the lock_extent() into cow_file_range() we can
push the extent locking into cow_file_range_inline() and move the
lock_extent in cow_file_range() to after we call
cow_file_range_inline().
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that cow_file_range is the only function that is called with the
range locked, push this call into cow_file_range so we can further
narrow the scope.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is used by zoned but also as the fallback for uncompressed extents
when we fail to compress the ranges. Push the extent lock into
run_dealloc_cow(), and adjust the compression case to take the extent
lock after calling run_delalloc_cow().
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since we immediately unlock the extent range when we enter
run_delalloc_compressed() simply move the lock_extent() down to cover
cow_file_range() and then remove the unlock_extent() from
run_delalloc_compressed.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
run_delalloc_nocow is a little special because we use the file extents
to see if we can nocow a range. We don't actually need the protection
of the extent lock to look at the file extents at this point however.
We are currently holding the page lock for this range, so we are
protected from anybody who would simultaneously be modifying the file
extent items for this range.
* mmap() - we're holding the page lock.
* buffered writes - we're holding the page lock.
* direct writes - we're holding the page lock and direct IO has to flush
page cache before it's able to continue.
* fallocate() - all callers flush the range and wait on ordered extents
while holding the inode lock and the mmap lock, so we are again saved
by the page lock.
We want to use the extent lock to protect
1) The mapping tree for the given range.
2) The ordered extents for the given range.
3) The io_tree for the given range.
Push the extent lock down to cover these operations. In the
fallback_to_cow() case we simply lock before doing anything and rely on
the cow_file_range() helper to handle it's range properly.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have the following pattern
while (1) {
if (cur_offset > end)
break;
}
Which is just
while (cur_offset <= end) {
...
}
so adjust the code to be more clear.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
run_delalloc_nocow is a bit special as it walks through the file extents
for the inode and determines what it can nocow and what it can't. This
is the more complicated area for extent locking, so start with this
function.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We want to limit the scope of the extent lock to be around operations
that can change in flight. Currently we hold the extent lock through
the entire writepage operation, which isn't really necessary.
We want to protect to make sure nobody has updated DELALLOC. In
find_lock_delalloc_range we must lock the range in order to validate the
contents of our io_tree. However once we've done that we're safe to
unlock the range and continue, as we have the page lock already held for
the range.
We are protected from all operations at this point.
* mmap() - we're holding the page lock, thus are protected.
* buffered writes - again, we're protected because we take the page lock
for the first and last page in our range for buffered writes so we
won't create new delalloc ranges in this area.
* direct IO - we invalidate pagecache before attempting to write a new
area, which requires the page lock, so again are protected once we're
holding the page lock on this range.
Additionally this behavior actually already exists for compressed, we
unlock the range as soon as we start to process the async extents, and
re-lock it during compression. So this is completely safe, and makes
the locking more consistent.
Make this simple by just pushing the extent lock into
btrfs_run_delalloc_range. From there followup patches will push the
lock further down into its users.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We currently don't lock the extent when we're doing a
cow_file_range_inline() for a compressed extent. This isn't a problem
necessarily, but it's inconsistent with the rest of our usage of
cow_file_range_inline(). This also leads to some extra weird logic
around whether the extent is locked or not. Fix this to lock the extent
before calling cow_file_range_inline() in compression to make it
consistent with the rest of the inline users. In future patches this
will be pushed down into the cow_file_range_inline() helper, so we're
fine with the quick and dirty locking here. This patch exists to make
the behavior change obvious.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We duplicate the extent cleanup for cow_file_range_inline() in the cow
and compressed case. The encoded case doesn't need to do cleanup the
same way, so rename cow_file_range_inline to __cow_file_range_inline and
then make cow_file_range_inline handle the extent cleanup appropriately,
and update the callers.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since 4750af3bbe ("btrfs: prevent extent_clear_unlock_delalloc() to
unlock page not locked by __process_pages_contig()") we have been
unlocking the locked page manually instead of via
extent_clear_unlock_delalloc() because of subpage blocksize support.
However we actually disable inline extent creation for subpage blocksize
support, so this behavior isn't necessary. Remove this code and
comment, if at some point the subpage blocksize code grows support for
inline extents this can be re-evaluated.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we have a lot of duplicated checks of
if (start == 0 && fs_info->sectorsize == PAGE_SIZE)
cow_file_range_inline();
Instead of duplicating this check everywhere, consolidate all of the
inline extent logic into a helper which documents all of the checks and
then use that helper inside of cow_file_range_inline(). With this we
can clean up all of the calls to either unconditionally call
cow_file_range_inline(), or at least reduce the checks we're doing
before we call cow_file_range_inline();
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the cow path we will clone the reloc csums for relocated data
extents, and if there's an error we already have an ordered extent and
rely on the ordered extent finishing to clean everything up.
There's a problem however, we don't mark the ordered extent with an
error, we pretend like everything was just fine. If we were at the end
of our range we won't actually bubble up this error anywhere, and we
could end up inserting an extent that doesn't have csums where it should
have them.
Fix this by adding a helper to mark the ordered extent with an error,
and then use this when we fail to lookup the csums in
btrfs_reloc_clone_csums. Use this helper in the other place where we
use the same pattern while we're here.
This will prevent us from erroneously inserting the extent that doesn't
have the required checksums.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function create_io_em() is called before we submit an IO, to update
the in-memory extent map for the involved range.
This patch changes the following aspects:
- Does not allow BTRFS_ORDERED_NOCOW type
For real NOCOW (excluding NOCOW writes into preallocated ranges)
writes, we never call create_io_em(), as we does not need to update
the extent map at all.
So remove the sanity check allowing BTRFS_ORDERED_NOCOW type.
- Add extra sanity checks
* PREALLOC
- @block_len == len
For uncompressed writes.
* REGULAR
- @block_len == @orig_block_len == @ram_bytes == @len
We're creating a new uncompressed extent, and referring all of it.
- @orig_start == @start
We haven no offset inside the extent.
* COMPRESSED
- valid @compress_type
- @len <= @ram_bytes
This is to co-operate with encoded writes, which can cause a new
file extent referring only part of a uncompressed extent.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With the tree-checker ensuring all inline file extents starts at file
offset 0 and has a length no larger than sectorsize, we can simplify the
calculation to assigned those fixes values directly.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The extent_map structure is very critical to btrfs, as it is involved
for both read and write paths.
Unfortunately the structure is not properly explained, making it pretty
hard to understand nor to do further improvement.
This patch adds extra comments explaining the major members based on my
code reading. Hopefully we can find more members to cleanup in the
future.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
calcu_metadata_size() has a "reserve" argument, but the only caller always
set it to "1". The other usage (reserve = 0) is dropped by a commit
0647bf564f ("Btrfs: improve forever loop when doing balance relocation"),
which is more than 10 years ago. Drop the argument and simplify the code.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's another return variable wret that is only passed to ret on
error, we can simply use ret.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
First, drop err instead reuse ret, choose to return the error instead of
goto fail and then return the same error. Do not initialize the ret
until where it has to be initialized. Slight logic change in handling
the btrfs_search_slot() and btrfs_next_leaf() return value.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rename ret to ret2 compile and then err to ret. Also, new ret2 is found
to be localized within the 'if (trans)' statement, so move its
declaration there.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In quick_update_accounting() err is used as 2nd return value, which could
be achieved just with ret.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Coding style fixes the function relocate_tree_blocks(). After the fix,
ret is the return value variable.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Code style fix in the function build_backref_tree(). Drop the ret
initialization 0, as we don't need it.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rename the function's local return variables err and werr to ret.
Also, align the variable declarations with the other declarations in
the function for better function space alignment.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rename the function's local variable werr and err to ret.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the function btrfs_write_marked_extents() and in __btrfs_wait_marked_extents()
return the actual error if when filemap_fdata<write|wait>_range() fails.
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are open coded tests of BTRFS_FS_STATE_DUMMY_FS_INFO and we have a
wrapper for that that's a compile-time constant when self-tests are not
built in. As this is only for development we can save some bytes and
conditions on release configs by using the helper in the remaining
cases.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to initialize the delayed inodes xarray with a GFP_ATOMIC
flag because that actually does nothing on the xarray operations. That was
needed for radix trees, but for xarrays the allocation flags are passed as
the last argument to xa_store() (which we are using correctly).
So initialize the delayed inodes xarray with a simple xa_init().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently try_release_extent_mapping() as an int return type, but we
use it as a boolean. Its only caller, the release folio callback, also
returns a boolean which corresponds to try_release_extent_mapping()'s
return value. So change its return value type to bool as well as its
helper try_release_extent_state().
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At try_release_extent_mapping(), called during the release folio callback
(btrfs_release_folio() callchain), we don't release any extent maps in the
range if the GFP flags don't allow blocking. This behaviour is exaggerated
because:
1) Both searching for extent maps and removing them are not blocking
operations. The only thing that it is the cond_resched() call at the
end of the loop that searches for and removes extent maps;
2) We currently only operate on a single page, so for the case where
block size matches the page size, we can only have one extent map,
and for the case where the block size is smaller than the page size,
we can have at most 16 extent maps.
So it's very unlikely the cond_resched() call will ever block even in the
block size smaller than page size scenario.
So instead of not removing any extent maps at all in case the GFP glags
don't allow blocking, keep removing extent maps while we don't need to
reschedule. This makes it safe for the subpage case and for a future
where we can process folios with a size larger than a page.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we don't attempt to release extent maps if the inode has an
i_size that is not greater than 16M. This condition was added way back
in 2008 by commit 70dec8079d ("Btrfs: extent_io and extent_state
optimizations"), without any explanation about it. A quick chat with
Chris on slack revealed that the goal was probably to release the extent
maps for small files only when closing the inode. This however can be
harmful in case we have tons of such files being kept open for very long
periods of time, since we will consume more and more pages for extent
maps.
So remove the condition.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Nowadays we have the btrfs_get_fs_generation() to get the current
generation of the filesystem, so there's no need anymore to lock the
transaction spinlock to read it.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rename the following variables:
1) "btrfs_inode" to "inode", because it's shorter to type and clear, and
we don't have a VFS inode here as well, so there's no confusion;
2) "tree" to "io_tree", to be clear which tree we are dealing with, since
we use 2 different trees in the function;
3) "map" to "extent_tree" since "map" gives the idea we are dealing with
an extent map for example, but we are dealing with the inode's extent
tree (the tree which stores extent maps).
These also make the next patches simpler.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add some tracepoints for the extent map shrinker to help debug and analyse
main events. These have proved useful during development of the shrinker.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Nowadays we have a lock used to synchronize mmap writes with reflink and
fsync operations (struct btrfs_inode::i_mmap_lock), so update the comment
for btrfs_set_inode_full_sync() to mention that it can also be called
while holding that mmap lock. Besides being a valid alternative to the
inode's VFS lock, we already have the extent map shrinker using that mmap
lock instead.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extent maps are used either to represent existing file extent items, or to
represent new extents that are going to be written and the respective file
extent items are created when the ordered extent completes.
We currently don't have any limit for how many extent maps we can have,
neither per inode nor globally. Most of the time this not too noticeable
because extent maps are removed in the following situations:
1) When evicting an inode;
2) When releasing folios (pages) through the btrfs_release_folio() address
space operation callback.
However we won't release extent maps in the folio range if the folio is
either dirty or under writeback or if the inode's i_size is less than
or equals to 16M (see try_release_extent_mapping(). This 16M i_size
constraint was added back in 2008 with commit 70dec8079d ("Btrfs:
extent_io and extent_state optimizations"), but there's no explanation
about why we have it or why the 16M value.
This means that for buffered IO we can reach an OOM situation due to too
many extent maps if either of the following happens:
1) There's a set of tasks constantly doing IO on many files with a size
not larger than 16M, specially if they keep the files open for very
long periods, therefore preventing inode eviction.
This requires a really high number of such files, and having many non
mergeable extent maps (due to random 4K writes for example) and a
machine with very little memory;
2) There's a set tasks constantly doing random write IO (therefore
creating many non mergeable extent maps) on files and keeping them
open for long periods of time, so inode eviction doesn't happen and
there's always a lot of dirty pages or pages under writeback,
preventing btrfs_release_folio() from releasing the respective extent
maps.
This second case was actually reported in the thread pointed by the Link
tag below, and it requires a very large file under heavy IO and a machine
with very little amount of RAM, which is probably hard to happen in
practice in a real world use case.
However when using direct IO this is not so hard to happen, because the
page cache is not used, and therefore btrfs_release_folio() is never
called. Which means extent maps are dropped only when evicting the inode,
and that means that if we have tasks that keep a file descriptor open and
keep doing IO on a very large file (or files), we can exhaust memory due
to an unbounded amount of extent maps. This is especially easy to happen
if we have a huge file with millions of small extents and their extent
maps are not mergeable (non contiguous offsets and disk locations).
This was reported in that thread with the following fio test:
$ cat test.sh
#!/bin/bash
DEV=/dev/sdj
MNT=/mnt/sdj
MOUNT_OPTIONS="-o ssd"
MKFS_OPTIONS=""
cat <<EOF > /tmp/fio-job.ini
[global]
name=fio-rand-write
filename=$MNT/fio-rand-write
rw=randwrite
bs=4K
direct=1
numjobs=16
fallocate=none
time_based
runtime=90000
[file1]
size=300G
ioengine=libaio
iodepth=16
EOF
umount $MNT &> /dev/null
mkfs.btrfs -f $MKFS_OPTIONS $DEV
mount $MOUNT_OPTIONS $DEV $MNT
fio /tmp/fio-job.ini
umount $MNT
Monitoring the btrfs_extent_map slab while running the test with:
$ watch -d -n 1 'cat /sys/kernel/slab/btrfs_extent_map/objects \
/sys/kernel/slab/btrfs_extent_map/total_objects'
Shows the number of active and total extent maps skyrocketing to tens of
millions, and on systems with a short amount of memory it's easy and quick
to get into an OOM situation, as reported in that thread.
So to avoid this issue add a shrinker that will remove extents maps, as
long as they are not pinned, and takes proper care with any concurrent
fsync to avoid missing extents (setting the full sync flag while in the
middle of a fast fsync). This shrinker is triggered through the callbacks
nr_cached_objects and free_cached_objects of struct super_operations.
The shrinker will iterate over all roots and over all inodes of each
root, and keeps track of the last scanned root and inode, so that the
next time it runs, it starts from that root and from the next inode.
This is similar to what xfs does for its inode reclaim (implements those
callbacks, and cycles through inodes by starting from where it ended
last time).
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a per cpu counter that tracks the total number of extent maps that are
in extent trees of inodes that belong to fs trees. This is going to be
used in an upcoming change that adds a shrinker for extent maps. Only
extent maps for fs trees are considered, because for special trees such as
the data relocation tree we don't want to evict their extent maps which
are critical for the relocation to work, and since those are limited, it's
not a concern to have them in memory during the relocation of a block
group. Another case are extent maps for free space cache inodes, which
must always remain in memory, but those are limited (there's only one per
free space cache inode, which means one per block group).
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extent maps are always associated to an inode's extent map tree, so
there's no need to pass the extent map tree explicitly to try_merge_map().
In order to facilitate an upcoming change that adds a shrinker for extent
maps, change try_merge_map() to receive the inode instead of its extent
map tree.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extent maps are always associated to an inode's extent map tree, so
there's no need to pass the extent map tree explicitly to
setup_extent_mapping().
In order to facilitate an upcoming change that adds a shrinker for extent
maps, change setup_extent_mapping() to receive the inode instead of its
extent map tree.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extent maps are always associated to an inode's extent map tree, so
there's no need to pass the extent map tree explicitly to
replace_extent_mapping().
In order to facilitate an upcoming change that adds a shrinker for extent
maps, change replace_extent_mapping() to receive the inode instead of its
extent map tree.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extent maps are always associated to an inode's extent map tree, so
there's no need to pass the extent map tree explicitly to
remove_extent_mapping().
In order to facilitate an upcoming change that adds a shrinker for extent
maps, change remove_extent_mapping() to receive the inode instead of its
extent map tree.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extent maps are always associated to an inode's extent map tree, so
there's no need to pass the extent map tree explicitly to
clear_em_logging().
In order to facilitate an upcoming change that adds a shrinker for extent
maps, change clear_em_logging() to receive the inode instead of its extent
map tree.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Extent maps are always added to an inode's extent map tree, so there's no
need to pass the extent map tree explicitly to add_extent_mapping().
In order to facilitate an upcoming change that adds a shrinker for extent
maps, change add_extent_mapping() to receive the inode instead of its
extent map tree.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
A comment from Filipe on one of my previous cleanups brought my
attention to a new helper we have for getting the root id of a root,
which makes it easier to read in the code.
The changes where made with the following Coccinelle semantic patch:
// <smpl>
@@
expression E,E1;
@@
(
E->root_key.objectid = E1
|
- E->root_key.objectid
+ btrfs_root_id(E)
)
// </smpl>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor style fixups ]
Signed-off-by: David Sterba <dsterba@suse.com>
Our subpage testing started hanging on generic/560 and I bisected it
down to 1cab1375ba ("btrfs: reuse cloned extent buffer during
fiemap to avoid re-allocations"). This is subtle because we use
eb->start to figure out where in the folio we're copying to when we're
subpage, as our ->start may refer to an area inside of the folio.
For example, assume a 16K page size machine with a 4K node size, and
assume that we already have a cloned extent buffer when we cloned the
previous search.
copy_extent_buffer_full() will do the following when copying the extent
buffer path->nodes[0] (src) into cloned (dest):
src->start = 8k; // this is the new leaf we're cloning
cloned->start = 4k; // this is left over from the previous clone
src_addr = folio_address(src->folios[0]);
dest_addr = folio_address(dest->folios[0]);
memcpy(dest_addr + get_eb_offset_in_folio(dst, 0),
src_addr + get_eb_offset_in_folio(src, 0), src->len);
Now get_eb_offset_in_folio() is where the problems occur, because for
sub-pagesize blocksize we can have multiple eb's per folio, the code for
this is as follows
size_t get_eb_offset_in_folio(eb, offset) {
return (eb->start + offset & (folio_size(eb->folio[0]) - 1));
}
So in the above example we are copying into offset 4K inside the folio.
However once we update cloned->start to 8K to match the src the math for
get_eb_offset_in_folio() changes, and any subsequent reads (i.e.
btrfs_item_key_to_cpu()) will start reading from the offset 8K instead
of 4K where we copied to, giving us garbage.
Fix this by setting start before we co copy_extent_buffer_full() to make
sure that we're copying into the same offset inside of the folio that we
will read from later.
All other sites of copy_extent_buffer_full() are correct because we
either set ->start beforehand or we simply don't change it in the case
of the tree-log usage.
With this fix we now pass generic/560 on our subpage tests.
Fixes: 1cab1375ba ("btrfs: reuse cloned extent buffer during fiemap to avoid re-allocations")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that these two structs are the same, move the btrfs_data_ref and
btrfs_tree_ref up and use these in the btrfs_delayed_ref_node. Then
remove the btrfs_delayed_*_ref structs.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we don't use these helpers anywhere, remove them.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We only ever need to use this to get the level of the tree block ref, so
use the btrfs_delayed_ref_owner() helper, which returns the level for
the given reference.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that most of our elements are inside of btrfs_delayed_ref_node
directly and we have helpers for the delayed_data_ref bits, go ahead and
remove all direct usage of btrfs_delayed_data_ref and use the helpers
where needed.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We don't need to pass in all the elements for the backrefs as function
arguments, simply pass through the btrfs_delayed_ref_node and then
extract the values we need from that.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have all the information we need in our btrfs_delayed_ref_node, which
we already pass into __btrfs_free_extent. Drop the extra arguments and
just extract the values from btrfs_delayed_ref_node.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're just extracting the values from btrfs_delayed_ref_node and passing
them through, simply pass the btrfs_delayed_ref_node into
__btrfs_inc_extent_ref and shrink the function arguments.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is how we refer to it in the rest of the extent reference related
code, make it consistent.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These two members are shared by both the tree refs and data refs, so
move them into btrfs_delayed_ref_node proper. This allows us to greatly
simplify the comparison code, as the shared refs always only sort on
parent, and the non shared refs always sort first on ref_root, and then
only data refs sort on their specific fields.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We consistently use ->num_bytes everywhere through the delayed ref code,
except in btrfs_ref. Rename btrfs_ref to match all the other code.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that these helpers are identical, create a helper function that
handles everything properly and strip the individual helpers down to use
just the common helper. This cleans up a significant amount of
duplicated code.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that all of the delayed ref information is in the delayed ref node,
drastically simplify the delayed ref tracepoints by simply passing in
the btrfs_delayed_ref_node and populating the tracepoints with the
values from the structure itself.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that the btrfs_delayed_ref_node contains a union of the data and
metadata specific information we can move the initialization into
init_delayed_ref_common and just use the btrfs_ref to initialize the
correct fields of the reference.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We are calling init_delayed_ref_head with all of the elements from
btrfs_ref, clean this up to simply pass in the btrfs_ref and initialize
the btrfs_delayed_ref_head with the values from the btrfs_ref directly.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're extracting all of these values from the btrfs_ref we passed in
already, just pass the btrfs_ref through to init_delayed_ref_common and
get the values directly from the struct.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have this in both btrfs_tree_ref and btrfs_data_ref, which is just
wasting space and making the code more complicated. Move this into
btrfs_ref proper and update all the call sites to do the assignment in
btrfs_ref.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_ref currently has ->owning_root, and ->ref_root is shared between
the tree ref and data ref, so in order to move that into btrfs_ref
proper I would need to add another root parameter to the initialization
function. This function has too many arguments, and adding another root
will make it easy to make mistakes about which root goes where.
Drop the generic ref init function and statically initialize the
btrfs_ref in every usage. This makes the code easier to read because we
can see what elements we're assigning, and will make the upcoming change
moving the ref_root into the btrfs_ref more clear and less error prone
than adding a new element to the initialization function.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have been embedding btrfs_delayed_ref_node in the
btrfs_delayed_data_ref and btrfs_delayed_tree_ref, and then we have two
sets of cachep's and a variety of handling that is awkward because of
this separation.
Instead union these two members inside of btrfs_delayed_ref_node and
make that the first class object. This allows us to go down to one
cachep for our delayed ref nodes instead of two.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have several different ways we refer to references throughout the
code and it's not consistent and there's a bit of duplication. In order
to clean this up I want to have one structure we use to define reference
information, and one structure we use for the delayed reference
information. Start this process by adding a helper to get from the
btrfs_delayed_data_ref/btrfs_delayed_tree_ref to the
btrfs_delayed_ref_node so that it'll make moving these structures around
simpler.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs_prune_dentries() has open code to find the first inode in
a root with a minimum inode number. Remove that code and make it use the
helper btrfs_find_first_inode() for that task.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Export the relocation private helper find_next_inode() to inode.c, as this
same logic is also used at btrfs_prune_dentries() and will be used by an
upcoming change that adds an extent map shrinker. The next patch will
change btrfs_prune_dentries() to use this helper.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The add_extent_mapping() function is short and trivial, there's no need to
have a label for a quick exit in case of an error, even because there's no
error handling needed, we just need to return the error. So remove that
label and return directly.
Also while at it remove the redundant initialization of 'ret', as that may
help avoid some warnings with clang tools such as the one reported/fixed
by commit 966de47ff0 ("btrfs: remove redundant initialization of
variables in log_new_ancestors").
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the extent map self tests, when freeing all extent maps from a test
extent map tree we are not expecting to find any extent map with a
reference count different from 1 (the tree reference). If we find any,
we just log a message but we don't fail the test, which makes it very easy
to miss any bug/regression - no one reads the test messages unless a test
fails. So change the behaviour to make a test fail if we find an extent
map in the tree with a reference count different from 1. Make the failure
happen only after removing all extent maps, so that we don't leak memory.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of passing fs_info and extent map tree arguments to
btrfs_add_extent_mapping(), we can pass an inode instead, as extent maps
are always inserted in the extent map tree of an inode, and the fs_info
can be extracted from the inode (inode->root->fs_info). The only exception
is in the self tests where we allocate an extent map tree and then use it
to insert/update/remove extent maps. However the tests can be changed to
use a test inode and then use the inode's extent map tree.
So change btrfs_add_extent_mapping() to have an inode as an argument
instead of a fs_info and an extent map tree. This reduces the number of
parameters and will also be needed for an upcoming change.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The csum_exist_in_range() function is now too trivial and is only used in
one place, so open code it in its single caller.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Before deciding if we can do a NOCOW write into a range, one of the things
we have to do is check if there are checksum items for that range. We do
that through the btrfs_lookup_csums_list() function, which searches for
checksums and adds them to a list supplied by the caller.
But all we need is to check if there is any checksum, we don't need to
look for all of them and collect them into a list, which requires more
search time in the checksums tree, allocating memory for checksums items
to add to the list, copy checksums from a leaf into those list items,
then free that memory, etc. This is all unnecessary overhead, wasting
mostly CPU time, and perhaps some occasional IO if we need to read from
disk any extent buffers.
So change btrfs_lookup_csums_list() to allow to return immediately in
case it finds any checksum, without the need to add it to a list and read
it from a leaf. This is accomplished by allowing a NULL list parameter and
making the function return 1 if it found any checksum, 0 if it didn't
found any, and a negative value in case of an error.
The following test with fio was used to measure performance:
$ cat test.sh
#!/bin/bash
DEV=/dev/nullb0
MNT=/mnt/nullb0
cat <<EOF > /tmp/fio-job.ini
[global]
name=fio-rand-write
filename=$MNT/fio-rand-write
rw=randwrite
bssplit=4k/20:8k/20:16k/20:32k/20:64k/20
direct=1
numjobs=16
fallocate=posix
time_based
runtime=300
[file1]
size=8G
ioengine=io_uring
iodepth=16
EOF
umount $MNT &> /dev/null
mkfs.btrfs -f $DEV
mount -o ssd $DEV $MNT
fio /tmp/fio-job.ini
umount $MNT
The test was run on a release kernel (Debian's default kernel config).
The results before this patch:
WRITE: bw=139MiB/s (146MB/s), 8204KiB/s-9504KiB/s (8401kB/s-9732kB/s), io=17.0GiB (18.3GB), run=125317-125344msec
The results after this patch:
WRITE: bw=153MiB/s (160MB/s), 9241KiB/s-10.0MiB/s (9463kB/s-10.5MB/s), io=17.0GiB (18.3GB), run=114054-114071msec
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the error path we have this while loop that keeps iterating over the
csums of the list and then delete them from the list and free them,
testing for an error (ret < 0) and list emptyness as the conditions of
the while loop.
Simplify this by using list_for_each_entry_safe() so there's no need to
delete elements from the list and need to test the error condition on
each iteration.
Also rename the 'fail' label to 'out' since the label is not exclusive
to a failure path, as we also end up there when the function succeeds,
and it's also a more common label name.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to use a temporary list to add the checksums, we can just
add them to input list and then on error delete and free any checksums
that were added. So simplify and remove the temporary list.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All the callers of btrfs_lookup_csums_list() pass a value of 0 as the
"search_commit" parameter. So remove it and make the function behave as
to always search from the regular root.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a function comment to btrfs_lookup_csums_list() to document it.
With another upcoming change its parameter list and return value will be
less obvious. So add the documentation now so that it can be updated where
needed later.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_page_mkwrite() is a struct vm_operations_struct callback and we
define that structure in file.c. Currently the function is in inode.c and
has to be exported to be used in file.c, which makes no sense because it's
not used anywhere else. So move btrfs_page_mkwrite() from inode.c and into
file.c.
While at it do a few minor style changes:
1) Capitalize the first word of every comment and end each sentence with
punctuation;
2) Avoid splitting some statements into two lines when everything fits in
85 characters or less.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are no more users of btrfs_clone_chunk_map(), the last one (and
only one ever) was removed in commit 1ec17ef591 ("btrfs: zoned: fix
use-after-free in do_zone_finish()"). So remove btrfs_clone_chunk_map().
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At warn_about_uncommitted_trans(), there's no need to check if the list
is empty and return, because list_for_each_entry_safe() is safe to call
for an empty list, it simply does nothing. So remove the check.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At btrfs_finish_one_ordered() it's pointless to assign 0 to the 'ret'
variable because if it has a non-zero value (error), we have already
jumped to the 'out' label. So remove that redundant assignment.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The mod_start and mod_len fields of struct extent_map were introduced by
commit 4e2f84e63d ("Btrfs: improve fsync by filtering extents that we
want") in order to avoid too low performance when fsyncing a file that
keeps getting extent maps merge, because it resulted in each fsync logging
again csum ranges that were already merged before.
We don't need this anymore as extent maps in the list of modified extents
are never merged with other extent maps and once we log an extent map we
remove it from the list of modified extent maps, so it's never logged
twice.
So remove the mod_start and mod_len fields from struct extent_map and use
instead the start and len fields when logging checksums in the fast fsync
path. This also makes EXTENT_FLAG_FILLING unused so remove it as well.
Running the reproducer from the commit mentioned before, with a larger
number of extents and against a null block device, so that IO is fast
and we can better see any impact from searching checksums items and
logging them, gave the following results from dd:
Before this change:
409600000 bytes (410 MB, 391 MiB) copied, 22.948 s, 17.8 MB/s
After this change:
409600000 bytes (410 MB, 391 MiB) copied, 22.9997 s, 17.8 MB/s
So no changes in throughput.
The test was done in a release kernel (non-debug, Debian's default kernel
config) and its steps are the following:
$ mkfs.btrfs -f /dev/nullb0
$ mount /dev/sdb /mnt
$ dd if=/dev/zero of=/mnt/foobar bs=4k count=100000 oflag=sync
$ umount /mnt
This also reduces the size of struct extent_map from 128 bytes down to 112
bytes, so now we can have 36 extents maps per 4K page instead of 32.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Some of the operations after the free might convert more PERTRANS
metadata. Do the freeing as late as possible to eliminate a source of
leaked PERTRANS metadata.
This helps with the pass rate of generic/269 and generic/475.
Reviewed-by: Qu Wenruo <qwu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
For both compression and decompression paths, we always require a
"struct page **pages" and "unsigned long nr_pages", this involves quite
some part of the btrfs compression paths:
- All the compression entry points
- compressed_bio structure
This affects both compression and decompression.
- async_extent structure
Unfortunately with all those involved parts, there is no good way to
split the conversion into smaller patches while still passing compiling.
So do this in one big conversion in one go.
Please note this is direct page->folio conversion, no change on the page
sized folio requirement yet.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor style fixups ]
Signed-off-by: David Sterba <dsterba@suse.com>
The new helper will do the same thing as btrfs_alloc_page_array(), but
with folios.
One extra difference is, there is no extra helper for bulk allocation,
thus it may not be as efficient as the page version.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since insert_inline_extent() now only accepts a single page, it's much
easier to convert it to use folio interfaces.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since our inline extent cannot accept anything larger than a sector,
there is really no need to pass all the compressed pages to
insert_inline_extent().
And just in case, expand the ASSERT()s to make sure we only try inline
with compressed size no larger than sectorsize.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we have two wrappers to allocate and free a page for
compression usage:
- btrfs_alloc_compr_page()
- btrfs_free_compr_page()
The allocator would try to grab a page from the pool, and only allocate
a new page if the pool is empty.
The reclaimer would check if the pool is full, and if not full it would
put the page into the pool.
This patch converts both helpers to use folio interfaces, and allowing
further conversion of compression path to folios.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For all the supported compression algorithms, the compression path would
always need to grab the page cache, then do the compression.
Normally we would get a page reference without any problem, since the
write path should have already locked the pages in the write range.
For the sake of error handling, we should handle the page cache miss
case.
Adds a common wrapper, btrfs_compress_find_get_page(), which calls
find_get_page(), and do the error handling along with an error message.
Callers inside compression path would only need to call
btrfs_compress_find_get_page(), and error out if it returned any error.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Nowadays before starting a reflink operation we do this:
1) Take the VFS lock of the inodes in exclusive mode (a rw semaphore);
2) Take the mmap lock of the inodes (struct btrfs_inode::i_mmap_lock);
3) Flush all delalloc in the source and target ranges;
4) Wait for all ordered extents in the source and target ranges to
complete;
5) Lock the source and destination ranges in the inodes' io trees.
In step 5 we lock the source range because:
1) We needed to serialize against mmap writes, but that is not needed
anymore because nowadays we do that through the inode's i_mmap_lock
(step 2). This happens since commit 8c99516a8c ("btrfs: exclude mmaps
while doing remap");
2) To serialize against a concurrent relocation and avoid generating
a delayed ref for an extent that was just dropped by relocation, see
commit d8b5524242 ("Btrfs: fix race between reflink/dedupe and
relocation").
Locking the source range however blocks any concurrent reads for that
range and makes test case generic/733 fail.
So instead of locking the source range during reflinks, make relocation
read lock the inode's i_mmap_lock, so that it serializes with a concurrent
reflink while still able to run concurrently with mmap writes and allow
concurrent reads too.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This check "if (inherit->num_qgroups > PAGE_SIZE)" is confusing and
unnecessary.
The problem with the check is that static checkers flag it as a
potential mixup of between units of bytes vs number of elements.
Fortunately, the check can safely be deleted because the next check is
correct and applies an even stricter limit:
if (size != struct_size(inherit, qgroups, inherit->num_qgroups))
return -EINVAL;
The "inherit" struct ends in a variable array of __u64 and
"inherit->num_qgroups" is the number of elements in the array. At the
start of the function we check that:
if (size < sizeof(*inherit) || size > PAGE_SIZE)
return -EINVAL;
Thus, since we verify that the whole struct fits within one page, that
means that the number of elements in the inherit->qgroups[] array must
be less than PAGE_SIZE.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use folio instead of page in put_file_data(). Add a warning in case
higher order folio is found, this will be implemented in the future.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Convert page references to folios and call the respective folio
functions. Since find_or_create_page() takes a mask argument, call
__filemap_get_folio() instead of filemap_grab_folio().
The patch assumes folio size is PAGE_SIZE, add a warning in case it's a
higher order that will be implemented in the future.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Convert usage of page to folio in prealloc_file_extent_cluster()
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unify naming of return value to the preferred way.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We recently tracked down a race condition that triggered a read for an
extent buffer with EXTENT_BUFFER_UPTODATE already set. While this read
was in progress, other concurrent readers would see the UPTODATE bit and
return early as if the read was already complete, making accesses to the
extent buffer conflict with the read operation that was overwriting it.
Add a WARN_ON() to end_bbio_meta_read() for this situation to make
similar races easier to spot in the future.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Tavian Barnes <tavianator@tavianator.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We are clearing the bit and waking up any waiters in two different
places. Factor that code out into a static helper function.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Tavian Barnes <tavianator@tavianator.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When unlocking a write lock on a drew lock, at btrfs_drew_write_unlock(),
it's pointless to wake up tasks waiting to acquire a read lock if we
didn't decrement the 'writers' counter down to 0, since a read lock can
only be acquired when the counter reaches a value of 0. Doing so is
harmless from a functional point of view, but it's not efficient due to
unnecessarily waking up tasks just for them to sleep again on the
waitqueue.
So change this to wake up readers only if we decremented the 'writers'
counter to 0.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no point in having a static writepages callback in inode.c that
does nothing besides calling extent_writepages from extent_io.c.
So just remove the callback at inode.c and rename extent_writepages()
to btrfs_writepages().
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no point in having a static readahead callback in inode.c that
does nothing besides calling extent_readahead() from extent_io.c.
So just remove the callback at inode.c and rename extent_readahead()
to btrfs_readahead().
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The __btrfs_tree_lock() and __btrfs_tree_read_lock() are using a naming
with a double underscore prefix, which is specially not proper for
exported functions. Remove the double underscore prefix from their name
and add the "_nested" suffix.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The functions btrfs_tree_lock() and btrfs_tree_read_lock() are very
trivial so that can be made inline and avoid call overhead, as they
are very often called inside critical sections (when searching a btree
for example, attempting to lock a child node/leaf while holding a lock
on the parent).
So make them static inline, which even reduces the size of the btrfs
module a little bit.
Before this change:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1718786 156276 16920 1891982 1cde8e fs/btrfs/btrfs.ko
After this change:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1718650 156260 16920 1891830 1cddf6 fs/btrfs/btrfs.ko
Running fs_mark also showed a tiny improvement with this script:
$ cat test.sh
#!/bin/bash
DEV=/dev/nullb0
MNT=/mnt/nullb0
FILES=100000
THREADS=$(nproc --all)
echo "performance" | \
tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
umount $DEV &> /dev/null
mkfs.btrfs -f $DEV
mount $DEV $MNT
OPTS="-S 0 -L 5 -n $FILES -s 0 -t $THREADS -k"
for ((i = 1; i <= $THREADS; i++)); do
OPTS="$OPTS -d $MNT/d$i"
done
fs_mark $OPTS
umount $MNT
Before this change:
FSUse% Count Size Files/sec App Overhead
10 1200000 0 180894.0 10705410
16 2400000 0 228211.4 10765738
23 3600000 0 215969.6 11011072
30 4800000 0 199077.1 11145587
46 6000000 0 176624.1 11658470
After this change:
FSUse% Count Size Files/sec App Overhead
10 1200000 0 185312.3 10708377
16 2400000 0 229320.4 10858013
23 3600000 0 217958.7 11006167
30 4800000 0 205122.9 11112899
46 6000000 0 178039.1 11438852
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When creating a snapshot we first check with btrfs_lookup_dir_item() if
there is a name collision in the parent directory and then return an error
if there's a collision. Then later on when trying to insert a dir item for
the snapshot we BUG_ON() if the return value is -EEXIST or -EOVERFLOW:
static noinline int create_pending_snapshot(...)
{
(...)
/* check if there is a file/dir which has the same name. */
dir_item = btrfs_lookup_dir_item(...);
(...)
ret = btrfs_insert_dir_item(...);
/* We have check then name at the beginning, so it is impossible. */
BUG_ON(ret == -EEXIST || ret == -EOVERFLOW);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto fail;
}
(...)
}
It's impossible to get the -EEXIST because we previously checked for a
potential collision with btrfs_lookup_dir_item() and we know that after
that no one could have added a colliding name because at this point the
transaction is in its critical section, state TRANS_STATE_COMMIT_DOING,
so no one can join this transaction to add a colliding name and neither
can anyone start a new transaction to do that.
As for the -EOVERFLOW, that can't happen as long as we have the extended
references feature enabled, which is a mkfs default for many years now.
In either case, the BUG_ON() is excessive as we can properly deal with
any error and can abort the transaction and jump to the 'fail' label,
in which case we'll also get the useful stack trace (just like a BUG_ON())
from the abort if the error is either -EEXIST or -EOVERFLOW.
So remove the BUG_ON().
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
bch2_write_super() was looping over online devices multiple times -
dropping and retaking io_ref each time.
This meant it could race with device removal; it could increment the
sequence number on a device but fail to write it - and then if the
device was re-added, it would get confused the next time around thinking
a superblock write was silently dropped.
Fix this by taking io_ref once, and stashing pointers to online devices
in a darray.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
'timeout' is a vague name for the return value of wait_event_*_timeout
because it actually returns the time left. Because the variable is never
used later, just drop the return value. Since variable 'timeout' is then
only used to carry a fixed timeout value, drop this in favor of a fixed
function argument as in the other call to wait_event_timeout() above.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
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Merge tag 'for-6.9-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"Two more fixes, both have some visible effects on user space:
- add check if quotas are enabled when passing qgroup inheritance
info, this affects snapper that could fail to create a snapshot
- do check for leaf/node flag WRITTEN earlier so that nodes are
completely validated before access, this used to be done by
integrity checker but it's been removed and left an unhandled case"
* tag 'for-6.9-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: make sure that WRITTEN is set on all metadata blocks
btrfs: qgroup: do not check qgroup inherit if qgroup is disabled
NFSERR_OPNOTSUPP is not described by any RFC, and should not be used.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The 'NFS error' NFSERR_OPNOTSUPP is not described by any of the official
NFS related RFCs, but appears to have snuck into some older .x files for
NFSv2.
Either way, it is not in RFC1094, RFC1813 or any of the NFSv4 RFCs, so
should not be returned by the knfsd server, and particularly not by the
"LOOKUP" operation.
Instead, let's return NFSERR_STALE, which is more appropriate if the
filesystem encodes the filehandle as FILEID_INVALID.
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
bch2_fs_quota_read_inode() wasn't entirely updated to the
bch2_snapshot_tree() helper, which takes rcu lock.
Reported-by: syzbot+a3a9a61224ed3b7f0010@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Ancient versions of bcachefs produced packed formats that could
represent keys that our in memory format cannot represent;
bformat_needs_redo() has some tricky shifts to check for this sort of
overflow.
Reported-by: syzbot+594427aebfefeebe91c6@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
For forwards compatibility we have to allow unknown key types, and only
run the checks that make sense against them.
Fix a missing guard on k.k->type being known.
Reported-by: syzbot+ae4dc916da3ce51f284f@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We were forgetting to check for jset entries that overrun the end of the
section - both in validate and to_text(); to_text() needs to be safe for
types that fail to validate.
Reported-by: syzbot+c48865e11e7e893ec4ab@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
filefrag (and potentially other utilities that call fiemap) sometimes
pass ULONG_MAX as the length. fiemap_prep clamps excessively large
lengths - but the calculation of end can overflow if it occurs before
calling fiemap_prep. When this happens, filefrag assumes it has read to
the end and exits.
Signed-off-by: Reed Riley <reed@riley.engineer>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The bucket_gens array is a single array allocation (one byte per
bucket), and kernel allocations are still limited to INT_MAX.
Check this limit to avoid failing the bucket_gens array allocation.
Reported-by: syzbot+b29f436493184ea42e2b@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
bch2_get_next_dev() and bch2_get_next_online_dev() iterate over devices,
dropping and taking refs as they go; we can't access the previous device
(for ca->dev_idx) after we've dropped our ref to it, unless we take
rcu_read_lock() first.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
bch2_dev_lookup() is supposed to take a ref on the device it returns, but
for_each_member_device() takes refs as it iterates,
for_each_member_device_rcu() does not.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Normally this is initialized in __bch2_write(), which is executed in a
loop, but the inline data path skips this.
Reported-by: syzbot+fd3ccb331eb21f05d13b@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We're using mutex_lock() inside a wait_event() conditional -
prepare_to_wait() has already flipped task state, so potentially
blocking ops need annotation.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Arnd Bergmann sent a patch to fsdevel, he says:
"orangefs_statfs() copies two consecutive fields of the superblock into
the statfs structure, which triggers a warning from the string fortification
helpers"
Jan Kara suggested an alternate way to do the patch to make it more readable.
I ran both ideas through xfstests and both seem fine. This patch
is based on Jan Kara's suggestion.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
When security labeling is enabled, the client can pass a file security
label as part of a create operation for the new file, similar to mode
and other attributes. At present, the security label is received by nfsd
and passed down to nfsd_create_setattr(), but nfsd_setattr() is never
called and therefore the label is never set on the new file. This bug
may have been introduced on or around commit d6a97d3f58 ("NFSD:
add security label to struct nfsd_attrs"). Looking at nfsd_setattr()
I am uncertain as to whether the same issue presents for
file ACLs and therefore requires a similar fix for those.
An alternative approach would be to introduce a new LSM hook to set the
"create SID" of the current task prior to the actual file creation, which
would atomically label the new inode at creation time. This would be better
for SELinux and a similar approach has been used previously
(see security_dentry_create_files_as) but perhaps not usable by other LSMs.
Reproducer:
1. Install a Linux distro with SELinux - Fedora is easiest
2. git clone https://github.com/SELinuxProject/selinux-testsuite
3. Install the requisite dependencies per selinux-testsuite/README.md
4. Run something like the following script:
MOUNT=$HOME/selinux-testsuite
sudo systemctl start nfs-server
sudo exportfs -o rw,no_root_squash,security_label localhost:$MOUNT
sudo mkdir -p /mnt/selinux-testsuite
sudo mount -t nfs -o vers=4.2 localhost:$MOUNT /mnt/selinux-testsuite
pushd /mnt/selinux-testsuite/
sudo make -C policy load
pushd tests/filesystem
sudo runcon -t test_filesystem_t ./create_file -f trans_test_file \
-e test_filesystem_filetranscon_t -v
sudo rm -f trans_test_file
popd
sudo make -C policy unload
popd
sudo umount /mnt/selinux-testsuite
sudo exportfs -u localhost:$MOUNT
sudo rmdir /mnt/selinux-testsuite
sudo systemctl stop nfs-server
Expected output:
<eliding noise from commands run prior to or after the test itself>
Process context:
unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: unconfined_u:object_r:test_filesystem_filetranscon_t:s0
File context is correct
Actual output:
<eliding noise from commands run prior to or after the test itself>
Process context:
unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: system_u:object_r:test_file_t:s0
File context error, expected:
test_filesystem_filetranscon_t
got:
test_file_t
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clients that send an OFFLOAD_STATUS might want to distinguish
between an async COPY operation that is still running, has
completed successfully, or that has failed.
The intention of this patch is to make NFSD behave like this:
* Copy still running:
OFFLOAD_STATUS returns NFS4_OK, the number of bytes copied
so far, and an empty osr_status array
* Copy completed successfully:
OFFLOAD_STATUS returns NFS4_OK, the number of bytes copied,
and an osr_status of NFS4_OK
* Copy failed:
OFFLOAD_STATUS returns NFS4_OK, the number of bytes copied,
and an osr_status other than NFS4_OK
* Copy operation lost, canceled, or otherwise unrecognized:
OFFLOAD_STATUS returns NFS4ERR_BAD_STATEID
NB: Though RFC 7862 Section 11.2 lists a small set of NFS status
codes that are valid for OFFLOAD_STATUS, there do not seem to be any
explicit spec limits on the status codes that may be returned in the
osr_status field.
At this time we have no unit tests for COPY and its brethren, as
pynfs does not yet implement support for NFSv4.2.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
After a client has started an asynchronous COPY operation, a
subsequent OFFLOAD_STATUS operation will need to report the status
code once that COPY operation has completed. The recorded status
record will be used by a subsequent patch.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Introduce write_ports netlink command. For listener-set, userspace is
expected to provide a NFS listeners list it wants enabled. All other
sockets will be closed.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Co-developed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Introduce write_version netlink command through a "declarative" interface.
This patch introduces a change in behavior since for version-set userspace
is expected to provide a NFS major/minor version list it wants to enable
while all the other ones will be disabled. (procfs write_version
command implements imperative interface where the admin writes +3/-3 to
enable/disable a single version.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Introduce write_threads netlink command similar to the one available
through the procfs.
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Co-developed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Currently admins set this by using unshare to create a new uts
namespace, and then resetting the hostname. With the new netlink
interface we can just pass this in directly. Prepare nfsd_svc for
this change.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Currently nfsd_svc holds the nfsd_mutex over the whole function. For
some of the later netlink patches though, we want to do some other
things to the server before starting it. Move the mutex handling into
the callers.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
In 'nlm_alloc_host', the host has already been assigned a value of NULL
when defined, so 'host=NULL;' Can be deleted.
Signed-off-by: Li kunyu <kunyu@nfschina.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
When CONFIG_NFSD_LEGACY_CLIENT_TRACKING is not set, the virtual file
/proc/fs/nfsd/nfsv4recoverydir
is created but responds EINVAL to any access.
This is not useful, is somewhat surprising, and it causes ltp to
complain.
The only known user of this file is in nfs-utils, which handles
non-existence and read-failure equally well. So there is nothing to
gain from leaving the file present but inaccessible.
So this patch removes the file when its content is not available - i.e.
when that config option is not selected.
Also remove the #ifdef which hides some of the enum values when
CONFIG_NFSD_V$ not selection. simple_fill_super() quietly ignores array
entries that are not present, so having slots in the array that don't
get used is perfectly acceptable. So there is no value in this #ifdef.
Reported-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Fixes: 74fd48739d ("nfsd: new Kconfig option for legacy client tracking")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
recalculate_deny_mode() takes time that is linear in the number of
stateids active on the file.
When called from
release_openowner -> free_ol_stateid_reaplist ->nfs4_free_ol_stateid
-> release_all_access
the number of times it is called is linear in the number of stateids.
The net result is that time taken by release_openowner is quadratic in
the number of stateids.
When the nfsd server is shut down while there are many active stateids
this can result in a soft lockup. ("CPU stuck for 302s" seen in one case).
In many cases all the states have the same deny modes and there is no
need to examine the entire list in recalculate_deny_mode(). In
particular, recalculate_deny_mode() will only reduce the deny mode,
never increase it. So if some prefix of the list causes the original
deny mode to be required, there is no need to examine the remainder of
the list.
So we can improve recalculate_deny_mode() to usually run in constant
time, so release_openowner will typically be only linear in the number
of states.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Show client info alongside the number of cl_rpc_users. If that's
elevated, then we can infer that this function returned nfserr_jukebox.
[ cel: For additional debugging of RPC user refcounting ]
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Vladimir Benes <vbenes@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Replace a dprintk in check_slot_seqid with tracepoints. These new
tracepoints track slot sequence numbers during operation.
Suggested-by: Jeffrey Layton <jlayton@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
We never want a newline in tracepoint output.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Vladimir Benes <vbenes@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Use group allocation/free of per-cpu counters api to accelerate
nfsd percpu_counters init/destroy(), and also squash the
nfsd_percpu_counters_init/reset/destroy() and nfsd_counters_init/destroy()
into callers to simplify code.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This adds basic infrastructure for handing GET_DIR_DELEGATION calls from
clients, including the decoders and encoders. For now, it always just
returns NFS4_OK + GDD4_UNAVAIL.
Eventually clients may start sending this operation, and it's better if
we can return GDD4_UNAVAIL instead of having to abort the whole compound.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit 8838203667 ("nfsd: update workqueue creation") made the
callback_wq single-threaded, presumably to protect modifications of
cl_cb_client. See documenting comment for nfsd4_process_cb_update().
However, cl_cb_client is per-lease. There's no other reason that all
callback operations need to be dispatched via a single thread. The
single threading here means all client callbacks can be blocked by a
problem with one client.
Change the NFSv4 callback client so it serializes per-lease instead
of serializing all NFSv4 callback operations on the server.
Reported-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
move_to_close_lru() is currently called with ->st_mutex held.
This can lead to a deadlock as move_to_close_lru() waits for sc_count to
drop to 2, and some threads holding a reference might be waiting for the
mutex. These references will never be dropped so sc_count will never
reach 2.
There can be no harm in dropping ->st_mutex before
move_to_close_lru() because the only place that takes the mutex is
nfsd4_lock_ol_stateid(), and it quickly aborts if sc_type is
NFS4_CLOSED_STID, which it will be before move_to_close_lru() is called.
See also
https://lore.kernel.org/lkml/4dd1fe21e11344e5969bb112e954affb@jd.com/T/
where this problem was raised but not successfully resolved.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
move_to_close_lru() waits for sc_count to become zero while holding
rp_mutex. This can deadlock if another thread holds a reference and is
waiting for rp_mutex.
By the time we get to move_to_close_lru() the openowner is unhashed and
cannot be found any more. So code waiting for the mutex can safely
retry the lookup if move_to_close_lru() has started.
So change rp_mutex to an atomic_t with three states:
RP_UNLOCK - state is still hashed, not locked for reply
RP_LOCKED - state is still hashed, is locked for reply
RP_UNHASHED - state is not hashed, no code can get a lock.
Use wait_var_event() to wait for either a lock, or for the owner to be
unhashed. In the latter case, retry the lookup.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Rather than taking the rp_mutex (via nfsd4_cstate_assign_replay) in
nfsd4_cleanup_open_state() (which seems counter-intuitive), take it and
assign rp_owner as soon as possible - in nfsd4_process_open1().
This will support a future change when nfsd4_cstate_assign_replay() might
fail.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Currently find_openstateowner_str look ups are done both in
nfsd4_process_open1() and alloc_init_open_stateowner() - the latter
possibly being a surprise based on its name.
It would be easier to follow, and more conformant to common patterns, if
the lookup was all in the one place.
So replace alloc_init_open_stateowner() with
find_or_alloc_open_stateowner() and use the latter in
nfsd4_process_open1() without any calls to find_openstateowner_str().
This means all finds are find_openstateowner_str_locked() and
find_openstateowner_str() is no longer needed. So discard
find_openstateowner_str() and rename find_openstateowner_str_locked() to
find_openstateowner_str().
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Combine the three boolean arguments into one flags argument for
readability.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Removes uses of page_mapping() and page_index().
Link: https://lkml.kernel.org/r/20240423225552.4113447-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Remove page_mapping()".
There are only a few users left. Convert them all to either call
folio_mapping() or just use folio->mapping directly.
This patch (of 6):
Remove uses of page->index, page_mapping() and b_page. Saves a call
to compound_head().
Link: https://lkml.kernel.org/r/20240423225552.4113447-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20240423225552.4113447-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Let's get rid of another page_mapcount() check and simply use
folio_likely_mapped_shared(), which is precise for hugetlb folios.
While at it, use huge_ptep_get() + pte_page() instead of ptep_get() +
vm_normal_page(), just like we do in pagemap_hugetlb_range().
No functional change intended.
Link: https://lkml.kernel.org/r/20240417092313.753919-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "fs/proc/task_mmu: convert hugetlb functions to work on folis".
Let's convert two more functions, getting rid of two more page_mapcount()
calls.
This patch (of 2):
Let's get rid of another page_mapcount() check and simply use
folio_likely_mapped_shared(), which is precise for hugetlb folios.
While at it, also check for PMD table sharing, like we do in
smaps_hugetlb_range().
No functional change intended, except that we would now detect hugetlb
folios shared via PMD table sharing correctly.
Link: https://lkml.kernel.org/r/20240417092313.753919-1-david@redhat.com
Link: https://lkml.kernel.org/r/20240417092313.753919-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add some more information about the state of the buffer_head returned.
Link: https://lkml.kernel.org/r/20240416031754.4076917-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Distinguish these functions from brelse() and __brelse().
Link: https://lkml.kernel.org/r/20240416031754.4076917-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Move the documentation for __brelse() to brelse(), format it as kernel-doc
and update it from talking about pages to folios.
Link: https://lkml.kernel.org/r/20240416031754.4076917-6-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The extra indentation confused the kernel-doc parser, so remove it. Fix
some other wording while I'm here, and advise the user they need to call
brelse() on this buffer.
__bread_gfp() isn't used directly by filesystems, but the other wrappers
for it don't have documentation, so document it accordingly.
Link: https://lkml.kernel.org/r/20240416031754.4076917-5-willy@infradead.org
Co-developed-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The documentation for this function has become separated from it over
time; move it to the right place and turn it into kernel-doc. Mild
editing of the content to make it more about what the function does, and
less about how it does it.
Link: https://lkml.kernel.org/r/20240416031754.4076917-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Turn the excellent documentation for this function into kernel-doc.
Replace 'page' with 'folio' and make a few other minor updates.
Link: https://lkml.kernel.org/r/20240416031754.4076917-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pagemap_scan_pmd_entry() checks if uffd-wp is set on each pte to avoid
unnecessary if set. However it was previously checking with
`pte_uffd_wp(ptep_get(pte))` without first confirming that the pte was
present. It is only valid to call pte_uffd_wp() for present ptes. For
swap ptes, pte_swp_uffd_wp() must be called because the uffd-wp bit may be
kept in a different position, depending on the arch.
This was leading to test failures in the pagemap_ioctl mm selftest, when
bringing up uffd-wp support on arm64 due to incorrectly interpretting the
uffd-wp status of migration entries.
Let's fix this by using the correct check based on pte_present(). While
we are at it, let's pass the pte to make_uffd_wp_pte() to avoid the
pointless extra ptep_get() which can't be optimized out due to READ_ONCE()
on many arches.
Link: https://lkml.kernel.org/r/20240429114104.182890-1-ryan.roberts@arm.com
Fixes: 12f6b01a0b ("fs/proc/task_mmu: add fast paths to get/clear PAGE_IS_WRITTEN flag")
Closes: https://lore.kernel.org/linux-arm-kernel/ZiuyGXt0XWwRgFh9@x1n/
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
make_uffd_wp_pte() was previously doing:
pte = ptep_get(ptep);
ptep_modify_prot_start(ptep);
pte = pte_mkuffd_wp(pte);
ptep_modify_prot_commit(ptep, pte);
But if another thread accessed or dirtied the pte between the first 2
calls, this could lead to loss of that information. Since
ptep_modify_prot_start() gets and clears atomically, the following is the
correct pattern and prevents any possible race. Any access after the
first call would see an invalid pte and cause a fault:
pte = ptep_modify_prot_start(ptep);
pte = pte_mkuffd_wp(pte);
ptep_modify_prot_commit(ptep, pte);
Link: https://lkml.kernel.org/r/20240429114017.182570-1-ryan.roberts@arm.com
Fixes: 52526ca7fd ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs")
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Userfaultfd unregister includes a step to remove wr-protect bits from all
the relevant pgtable entries, but that only covered an explicit
UFFDIO_UNREGISTER ioctl, not a close() on the userfaultfd itself. Cover
that too. This fixes a WARN trace.
The only user visible side effect is the user can observe leftover
wr-protect bits even if the user close()ed on an userfaultfd when
releasing the last reference of it. However hopefully that should be
harmless, and nothing bad should happen even if so.
This change is now more important after the recent page-table-check
patch we merged in mm-unstable (446dd9ad37d0 ("mm/page_table_check:
support userfault wr-protect entries")), as we'll do sanity check on
uffd-wp bits without vma context. So it's better if we can 100%
guarantee no uffd-wp bit leftovers, to make sure each report will be
valid.
Link: https://lore.kernel.org/all/000000000000ca4df20616a0fe16@google.com/
Fixes: f369b07c86 ("mm/uffd: reset write protection when unregister with wp-mode")
Analyzed-by: David Hildenbrand <david@redhat.com>
Link: https://lkml.kernel.org/r/20240422133311.2987675-1-peterx@redhat.com
Reported-by: syzbot+d8426b591c36b21c750e@syzkaller.appspotmail.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
epoll can call out to vfs_poll() with a file pointer that may race with
the last 'fput()'. That would make f_count go down to zero, and while
the ep->mtx locking means that the resulting file pointer tear-down will
be blocked until the poll returns, it means that f_count is already
dead, and any use of it won't actually get a reference to the file any
more: it's dead regardless.
Make sure we have a valid ref on the file pointer before we call down to
vfs_poll() from the epoll routines.
Link: https://lore.kernel.org/lkml/0000000000002d631f0615918f1e@google.com/
Reported-by: syzbot+045b454ab35fd82a35fb@syzkaller.appspotmail.com
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fix RCU callback of freeing an eventfs_inode.
The freeing of the eventfs_inode from the kref going to zero
freed the contents of the eventfs_inode and then used kfree_rcu()
to free the inode itself. But the contents should also be protected
by RCU. Switch to a call_rcu() that calls a function to free all
of the eventfs_inode after the RCU synchronization.
- The tracing subsystem maps its own descriptor to a file represented by
eventfs. The freeing of this descriptor needs to know when the
last reference of an eventfs_inode is released, but currently
there is no interface for that. Add a "release" callback to
the eventfs_inode entry array that allows for freeing of data
that can be referenced by the eventfs_inode being opened.
Then increment the ref counter for this descriptor when the
eventfs_inode file is created, and decrement/free it when the
last reference to the eventfs_inode is released and the file
is removed. This prevents races between freeing the descriptor
and the opening of the eventfs file.
- Fix the permission processing of eventfs.
The change to make the permissions of eventfs default to the mount
point but keep track of when changes were made had a side effect
that could cause security concerns. When the tracefs is remounted
with a given gid or uid, all the files within it should inherit
that gid or uid. But if the admin had changed the permission of
some file within the tracefs file system, it would not get updated
by the remount. This caused the kselftest of file permissions
to fail the second time it is run. The first time, all changes
would look fine, but the second time, because the changes were
"saved", the remount did not reset them.
Create a link list of all existing tracefs inodes, and clear the
saved flags on them on a remount if the remount changes the
corresponding gid or uid fields.
This also simplifies the code by removing the distinction between the
toplevel eventfs and an instance eventfs. They should both act the
same. They were different because of a misconception due to the
remount not resetting the flags. Now that remount resets all the
files and directories to default to the root node if a uid/gid is
specified, it makes the logic simpler to implement.
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Merge tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing and tracefs fixes from Steven Rostedt:
- Fix RCU callback of freeing an eventfs_inode.
The freeing of the eventfs_inode from the kref going to zero freed
the contents of the eventfs_inode and then used kfree_rcu() to free
the inode itself. But the contents should also be protected by RCU.
Switch to a call_rcu() that calls a function to free all of the
eventfs_inode after the RCU synchronization.
- The tracing subsystem maps its own descriptor to a file represented
by eventfs. The freeing of this descriptor needs to know when the
last reference of an eventfs_inode is released, but currently there
is no interface for that.
Add a "release" callback to the eventfs_inode entry array that allows
for freeing of data that can be referenced by the eventfs_inode being
opened. Then increment the ref counter for this descriptor when the
eventfs_inode file is created, and decrement/free it when the last
reference to the eventfs_inode is released and the file is removed.
This prevents races between freeing the descriptor and the opening of
the eventfs file.
- Fix the permission processing of eventfs.
The change to make the permissions of eventfs default to the mount
point but keep track of when changes were made had a side effect that
could cause security concerns. When the tracefs is remounted with a
given gid or uid, all the files within it should inherit that gid or
uid. But if the admin had changed the permission of some file within
the tracefs file system, it would not get updated by the remount.
This caused the kselftest of file permissions to fail the second time
it is run. The first time, all changes would look fine, but the
second time, because the changes were "saved", the remount did not
reset them.
Create a link list of all existing tracefs inodes, and clear the
saved flags on them on a remount if the remount changes the
corresponding gid or uid fields.
This also simplifies the code by removing the distinction between the
toplevel eventfs and an instance eventfs. They should both act the
same. They were different because of a misconception due to the
remount not resetting the flags. Now that remount resets all the
files and directories to default to the root node if a uid/gid is
specified, it makes the logic simpler to implement.
* tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
eventfs: Have "events" directory get permissions from its parent
eventfs: Do not treat events directory different than other directories
eventfs: Do not differentiate the toplevel events directory
tracefs: Still use mount point as default permissions for instances
tracefs: Reset permissions on remount if permissions are options
eventfs: Free all of the eventfs_inode after RCU
eventfs/tracing: Add callback for release of an eventfs_inode
This patch fix xfstests generic/070 test with smb2 leases = yes.
cifs.ko doesn't set parent lease key and epoch in create context v2 lease.
ksmbd suppose that parent lease and epoch are vaild if data length is
v2 lease context size and handle directory lease using this values.
ksmbd should hanle it as v1 lease not v2 lease if parent lease key and
epoch are not set in create context v2 lease.
Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
lease break wait for lease break acknowledgment.
rwsem is more suitable than unlock while traversing the list for parent
lease break in ->m_op_list.
Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch fixes generic/011 when enable smb2 leases.
if ksmbd sends multiple notifications for a file, cifs increments
the reference count of the file but it does not decrement the count by
the failure of queue_work.
So even if the file is closed, cifs does not send a SMB2_CLOSE request.
Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
ΕΛΕΝΗ reported that ksmbd binds to the IPV6 wildcard (::) by default for
ipv4 and ipv6 binding. So IPV4 connections are successful only when
the Linux system parameter bindv6only is set to 0 [default value].
If this parameter is set to 1, then the ipv6 wildcard only represents
any IPV6 address. Samba creates different sockets for ipv4 and ipv6
by default. This patch off sk_ipv6only to support IPV4/IPV6 connections
without creating two sockets.
Cc: stable@vger.kernel.org
Reported-by: ΕΛΕΝΗ ΤΖΑΒΕΛΛΑ <helentzavellas@yahoo.gr>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
The events directory gets its permissions from the root inode. But this
can cause an inconsistency if the instances directory changes its
permissions, as the permissions of the created directories under it should
inherit the permissions of the instances directory when directories under
it are created.
Currently the behavior is:
# cd /sys/kernel/tracing
# chgrp 1002 instances
# mkdir instances/foo
# ls -l instances/foo
[..]
-r--r----- 1 root lkp 0 May 1 18:55 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 18:55 current_tracer
-rw-r----- 1 root lkp 0 May 1 18:55 error_log
drwxr-xr-x 1 root root 0 May 1 18:55 events
--w------- 1 root lkp 0 May 1 18:55 free_buffer
drwxr-x--- 2 root lkp 0 May 1 18:55 options
drwxr-x--- 10 root lkp 0 May 1 18:55 per_cpu
-rw-r----- 1 root lkp 0 May 1 18:55 set_event
All the files and directories under "foo" has the "lkp" group except the
"events" directory. That's because its getting its default value from the
mount point instead of its parent.
Have the "events" directory make its default value based on its parent's
permissions. That now gives:
# ls -l instances/foo
[..]
-rw-r----- 1 root lkp 0 May 1 21:16 buffer_subbuf_size_kb
-r--r----- 1 root lkp 0 May 1 21:16 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 21:16 current_tracer
-rw-r----- 1 root lkp 0 May 1 21:16 error_log
drwxr-xr-x 1 root lkp 0 May 1 21:16 events
--w------- 1 root lkp 0 May 1 21:16 free_buffer
drwxr-x--- 2 root lkp 0 May 1 21:16 options
drwxr-x--- 10 root lkp 0 May 1 21:16 per_cpu
-rw-r----- 1 root lkp 0 May 1 21:16 set_event
Link: https://lore.kernel.org/linux-trace-kernel/20240502200906.161887248@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Treat the events directory the same as other directories when it comes to
permissions. The events directory was considered different because it's
dentry is persistent, whereas the other directory dentries are created
when accessed. But the way tracefs now does its ownership by using the
root dentry's permissions as the default permissions, the events directory
can get out of sync when a remount is performed setting the group and user
permissions.
Remove the special case for the events directory on setting the
attributes. This allows the updates caused by remount to work properly as
well as simplifies the code.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200906.002923579@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The toplevel events directory is really no different than the events
directory of instances. Having the two be different caused
inconsistencies and made it harder to fix the permissions bugs.
Make all events directories act the same.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200905.846448710@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
If the instances directory's permissions were never change, then have it
and its children use the mount point permissions as the default.
Currently, the permissions of instance directories are determined by the
instance directory's permissions itself. But if the tracefs file system is
remounted and changes the permissions, the instance directory and its
children should use the new permission.
But because both the instance directory and its children use the instance
directory's inode for permissions, it misses the update.
To demonstrate this:
# cd /sys/kernel/tracing/
# mkdir instances/foo
# ls -ld instances/foo
drwxr-x--- 5 root root 0 May 1 19:07 instances/foo
# ls -ld instances
drwxr-x--- 3 root root 0 May 1 18:57 instances
# ls -ld current_tracer
-rw-r----- 1 root root 0 May 1 18:57 current_tracer
# mount -o remount,gid=1002 .
# ls -ld instances
drwxr-x--- 3 root root 0 May 1 18:57 instances
# ls -ld instances/foo/
drwxr-x--- 5 root root 0 May 1 19:07 instances/foo/
# ls -ld current_tracer
-rw-r----- 1 root lkp 0 May 1 18:57 current_tracer
Notice that changing the group id to that of "lkp" did not affect the
instances directory nor its children. It should have been:
# ls -ld current_tracer
-rw-r----- 1 root root 0 May 1 19:19 current_tracer
# ls -ld instances/foo/
drwxr-x--- 5 root root 0 May 1 19:25 instances/foo/
# ls -ld instances
drwxr-x--- 3 root root 0 May 1 19:19 instances
# mount -o remount,gid=1002 .
# ls -ld current_tracer
-rw-r----- 1 root lkp 0 May 1 19:19 current_tracer
# ls -ld instances
drwxr-x--- 3 root lkp 0 May 1 19:19 instances
# ls -ld instances/foo/
drwxr-x--- 5 root lkp 0 May 1 19:25 instances/foo/
Where all files were updated by the remount gid update.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200905.686838327@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
There's an inconsistency with the way permissions are handled in tracefs.
Because the permissions are generated when accessed, they default to the
root inode's permission if they were never set by the user. If the user
sets the permissions, then a flag is set and the permissions are saved via
the inode (for tracefs files) or an internal attribute field (for
eventfs).
But if a remount happens that specify the permissions, all the files that
were not changed by the user gets updated, but the ones that were are not.
If the user were to remount the file system with a given permission, then
all files and directories within that file system should be updated.
This can cause security issues if a file's permission was updated but the
admin forgot about it. They could incorrectly think that remounting with
permissions set would update all files, but miss some.
For example:
# cd /sys/kernel/tracing
# chgrp 1002 current_tracer
# ls -l
[..]
-rw-r----- 1 root root 0 May 1 21:25 buffer_size_kb
-rw-r----- 1 root root 0 May 1 21:25 buffer_subbuf_size_kb
-r--r----- 1 root root 0 May 1 21:25 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 21:25 current_tracer
-rw-r----- 1 root root 0 May 1 21:25 dynamic_events
-r--r----- 1 root root 0 May 1 21:25 dyn_ftrace_total_info
-r--r----- 1 root root 0 May 1 21:25 enabled_functions
Where current_tracer now has group "lkp".
# mount -o remount,gid=1001 .
# ls -l
-rw-r----- 1 root tracing 0 May 1 21:25 buffer_size_kb
-rw-r----- 1 root tracing 0 May 1 21:25 buffer_subbuf_size_kb
-r--r----- 1 root tracing 0 May 1 21:25 buffer_total_size_kb
-rw-r----- 1 root lkp 0 May 1 21:25 current_tracer
-rw-r----- 1 root tracing 0 May 1 21:25 dynamic_events
-r--r----- 1 root tracing 0 May 1 21:25 dyn_ftrace_total_info
-r--r----- 1 root tracing 0 May 1 21:25 enabled_functions
Everything changed but the "current_tracer".
Add a new link list that keeps track of all the tracefs_inodes which has
the permission flags that tell if the file/dir should use the root inode's
permission or not. Then on remount, clear all the flags so that the
default behavior of using the root inode's permission is done for all
files and directories.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200905.529542160@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The freeing of eventfs_inode via a kfree_rcu() callback. But the content
of the eventfs_inode was being freed after the last kref. This is
dangerous, as changes are being made that can access the content of an
eventfs_inode from an RCU loop.
Instead of using kfree_rcu() use call_rcu() that calls a function to do
all the freeing of the eventfs_inode after a RCU grace period has expired.
Link: https://lore.kernel.org/linux-trace-kernel/20240502200905.370261163@goodmis.org
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: 43aa6f97c2 ("eventfs: Get rid of dentry pointers without refcounts")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Synthetic events create and destroy tracefs files when they are created
and removed. The tracing subsystem has its own file descriptor
representing the state of the events attached to the tracefs files.
There's a race between the eventfs files and this file descriptor of the
tracing system where the following can cause an issue:
With two scripts 'A' and 'B' doing:
Script 'A':
echo "hello int aaa" > /sys/kernel/tracing/synthetic_events
while :
do
echo 0 > /sys/kernel/tracing/events/synthetic/hello/enable
done
Script 'B':
echo > /sys/kernel/tracing/synthetic_events
Script 'A' creates a synthetic event "hello" and then just writes zero
into its enable file.
Script 'B' removes all synthetic events (including the newly created
"hello" event).
What happens is that the opening of the "enable" file has:
{
struct trace_event_file *file = inode->i_private;
int ret;
ret = tracing_check_open_get_tr(file->tr);
[..]
But deleting the events frees the "file" descriptor, and a "use after
free" happens with the dereference at "file->tr".
The file descriptor does have a reference counter, but there needs to be a
way to decrement it from the eventfs when the eventfs_inode is removed
that represents this file descriptor.
Add an optional "release" callback to the eventfs_entry array structure,
that gets called when the eventfs file is about to be removed. This allows
for the creating on the eventfs file to increment the tracing file
descriptor ref counter. When the eventfs file is deleted, it can call the
release function that will call the put function for the tracing file
descriptor.
This will protect the tracing file from being freed while a eventfs file
that references it is being opened.
Link: https://lore.kernel.org/linux-trace-kernel/20240426073410.17154-1-Tze-nan.Wu@mediatek.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240502090315.448cba46@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 5790b1fb3d ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Tze-nan wu <Tze-nan.Wu@mediatek.com>
Tested-by: Tze-nan Wu (吳澤南) <Tze-nan.Wu@mediatek.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
