Conversion performed via this Coccinelle script:
// SPDX-License-Identifier: GPL-2.0-only
// Options: --include-headers-for-types --all-includes --include-headers --keep-comments
virtual patch
@gfp depends on patch && !(file in "tools") && !(file in "samples")@
identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
kzalloc_obj,kzalloc_objs,kzalloc_flex,
kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
@@
ALLOC(...
- , GFP_KERNEL
)
$ make coccicheck MODE=patch COCCI=gfp.cocci
Build and boot tested x86_64 with Fedora 42's GCC and Clang:
Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
Pull ext4 updates from Ted Ts'o:
"New features and improvements for the ext4 file system
- Avoid unnecessary cache invalidation in the extent status cache
(es_cache) when adding extents to be cached in the es_cache and we
are not changing the extent tree
- Add a sysfs parameter, err_report_sec, to control how frequently to
log a warning message that file system inconsistency has been
detected (Previously we logged the warning message every 24 hours)
- Avoid unnecessary forced ordered writes when appending to a file
when delayed allocation is enabled
- Defer splitting unwritten extents to I/O completion to improve
write performance of concurrent direct I/O writes to multiple files
- Refactor and add kunit tests to the extent splitting and conversion
code paths
Various Bug Fixes:
- Fix a panic when the debugging DOUBLE_CHECK macro is defined
- Avoid using fast commit for rare and complex file system operations
to make fast commit easier to reason about. This can also avoid
some corner cases that could result in file system inconsistency if
there is a crash between the fast commit before a subsequent full
commit
- Fix memory leaks in error paths
- Fix a false positive reports caused when running stress tests using
mixed huge-page workloads caused by a race between page migration
and bitmap updates
- Fix a potential recursion into file system reclaim when evicting an
inode when fast commit is enabled
- Fix a warning caused by a potential double decrement to the dirty
clusters counter when executing FS_IOC_SHUTDOWN when running a
stress test
- Enable mballoc optimized scanning regardless whether the inode is
using indirect blocks or extent trees to map blocks"
* tag 'ext4_for_linus-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (45 commits)
et4: allow zeroout when doing written to unwritten split
ext4: refactor split and convert extents
ext4: refactor zeroout path and handle all cases
ext4: propagate flags to ext4_convert_unwritten_extents_endio()
ext4: propagate flags to convert_initialized_extent()
ext4: add extent status cache support to kunit tests
ext4: kunit tests for higher level extent manipulation functions
ext4: kunit tests for extent splitting and conversion
ext4: use optimized mballoc scanning regardless of inode format
ext4: always allocate blocks only from groups inode can use
ext4: fix dirtyclusters double decrement on fs shutdown
ext4: fast commit: make s_fc_lock reclaim-safe
ext4: fix e4b bitmap inconsistency reports
ext4: remove redundant NULL check after __GFP_NOFAIL
ext4: remove EXT4_GET_BLOCKS_IO_CREATE_EXT
ext4: simplify the mapping query logic in ext4_iomap_begin()
ext4: remove unused unwritten parameter in ext4_dio_write_iter()
ext4: remove useless ext4_iomap_overwrite_ops
ext4: avoid starting handle when dio writing an unwritten extent
ext4: don't split extent before submitting I/O
...
Currently we don't used mballoc optimized scanning (using max free
extent order and avg free extent order group lists) for inodes with
indirect block based format. This is confusing for users and I don't see
a good reason for that. Even with indirect block based inode format we
can spend big amount of time searching for free blocks for large
filesystems with fragmented free space. To add to the confusion before
commit 077d0c2c78df ("ext4: make mb_optimize_scan performance mount
option work with extents") optimized scanning was applied *only* to
indirect block based inodes so that commit appears as a performance
regression to some users. Just use optimized scanning whenever it is
enabled by mount options.
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Link: https://patch.msgid.link/20260114182836.14120-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
For filesystems with more than 2^32 blocks inodes using indirect block based format cannot use blocks beyond the 32-bit limit. ext4_mb_scan_groups_linear() takes care to not select these unsupported groups for such inodes however other functions selecting groups for allocation don't. So far this is harmless because the other selection functions are used only with mb_optimize_scan and this is currently disabled for inodes with indirect blocks however in the following patch we want to enable mb_optimize_scan regardless of inode format. Reviewed-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Pedro Falcato <pfalcato@suse.de> Cc: stable@kernel.org Link: https://patch.msgid.link/20260114182836.14120-3-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fstests test generic/388 occasionally reproduces a warning in
ext4_put_super() associated with the dirty clusters count:
WARNING: CPU: 7 PID: 76064 at fs/ext4/super.c:1324 ext4_put_super+0x48c/0x590 [ext4]
Tracing the failure shows that the warning fires due to an
s_dirtyclusters_counter value of -1. IOW, this appears to be a
spurious decrement as opposed to some sort of leak. Further tracing
of the dirty cluster count deltas and an LLM scan of the resulting
output identified the cause as a double decrement in the error path
between ext4_mb_mark_diskspace_used() and the caller
ext4_mb_new_blocks().
First, note that generic/388 is a shutdown vs. fsstress test and so
produces a random set of operations and shutdown injections. In the
problematic case, the shutdown triggers an error return from the
ext4_handle_dirty_metadata() call(s) made from
ext4_mb_mark_context(). The changed value is non-zero at this point,
so ext4_mb_mark_diskspace_used() does not exit after the error
bubbles up from ext4_mb_mark_context(). Instead, the former
decrements both cluster counters and returns the error up to
ext4_mb_new_blocks(). The latter falls into the !ar->len out path
which decrements the dirty clusters counter a second time, creating
the inconsistency.
To avoid this problem and simplify ownership of the cluster
reservation in this codepath, lift the counter reduction to a single
place in the caller. This makes it more clear that
ext4_mb_new_blocks() is responsible for acquiring cluster
reservation (via ext4_claim_free_clusters()) in the !delalloc case
as well as releasing it, regardless of whether it ends up consumed
or returned due to failure.
Fixes: 0087d9fb3f29 ("ext4: Fix s_dirty_blocks_counter if block allocation failed with nodelalloc")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Link: https://patch.msgid.link/20260113171905.118284-1-bfoster@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
A bitmap inconsistency issue was observed during stress tests under
mixed huge-page workloads. Ext4 reported multiple e4b bitmap check
failures like:
ext4_mb_complex_scan_group:2508: group 350, 8179 free clusters as
per group info. But got 8192 blocks
Analysis and experimentation confirmed that the issue is caused by a
race condition between page migration and bitmap modification. Although
this timing window is extremely narrow, it is still hit in practice:
folio_lock ext4_mb_load_buddy
__migrate_folio
check ref count
folio_mc_copy __filemap_get_folio
folio_try_get(folio)
......
mb_mark_used
ext4_mb_unload_buddy
__folio_migrate_mapping
folio_ref_freeze
folio_unlock
The root cause of this issue is that the fast path of load_buddy only
increments the folio's reference count, which is insufficient to prevent
concurrent folio migration. We observed that the folio migration process
acquires the folio lock. Therefore, we can determine whether to take the
fast path in load_buddy by checking the lock status. If the folio is
locked, we opt for the slow path (which acquires the lock) to close this
concurrency window.
Additionally, this change addresses the following issues:
When the DOUBLE_CHECK macro is enabled to inspect bitmap-related
issues, the following error may be triggered:
corruption in group 324 at byte 784(6272): f in copy != ff on
disk/prealloc
Analysis reveals that this is a false positive. There is a specific race
window where the bitmap and the group descriptor become momentarily
inconsistent, leading to this error report:
ext4_mb_load_buddy ext4_mb_load_buddy
__filemap_get_folio(create|lock)
folio_lock
ext4_mb_init_cache
folio_mark_uptodate
__filemap_get_folio(no lock)
......
mb_mark_used
mb_mark_used_double
mb_cmp_bitmaps
mb_set_bits(e4b->bd_bitmap)
folio_unlock
The original logic assumed that since mb_cmp_bitmaps is called when the
bitmap is newly loaded from disk, the folio lock would be sufficient to
prevent concurrent access. However, this overlooks a specific race
condition: if another process attempts to load buddy and finds the folio
is already in an uptodate state, it will immediately begin using it without
holding folio lock.
Signed-off-by: Yongjian Sun <sunyongjian1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260106090820.836242-1-sunyongjian@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
min_t(unsigned int, a, b) casts an 'unsigned long' to 'unsigned int'.
Use min(a, b) instead as it promotes any 'unsigned int' to 'unsigned long'
and so cannot discard significant bits.
A couple of places need umin() because of loops like:
nfolios = DIV_ROUND_UP(ret + start, PAGE_SIZE);
for (i = 0; i < nfolios; i++) {
struct folio *folio = page_folio(pages[i]);
...
unsigned int len = umin(ret, PAGE_SIZE - start);
...
ret -= len;
...
}
where the compiler doesn't track things well enough to know that
'ret' is never negative.
The alternate loop:
for (i = 0; ret > 0; i++) {
struct folio *folio = page_folio(pages[i]);
...
unsigned int len = min(ret, PAGE_SIZE - start);
...
ret -= len;
...
}
would be equivalent and doesn't need 'nfolios'.
Most of the 'unsigned long' actually come from PAGE_SIZE.
Detected by an extra check added to min_t().
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Link: https://patch.msgid.link/20251119224140.8616-31-david.laight.linux@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
The ext4 multi-block allocator now fully supports folio objects. Update all variable names, function names, and comments to replace legacy 'page' terminology with 'folio', improving clarity and consistency. No functional changes. Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Message-ID: <20251121090654.631996-16-libaokun@huaweicloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>