We should not truncate replaced blocks, and were supposed to truncate the first
part as well.
This reverts commit 78a99fe625.
Cc: stable@vger.kernel.org
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
To fix a race condition between atomic write aborts, I use the inode
lock and make COW inode to be re-usable thoroughout the whole
atomic file inode lifetime.
Reported-by: syzbot+823000d23b3400619f7c@syzkaller.appspotmail.com
Fixes: 3db1de0e58 ("f2fs: change the current atomic write way")
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch is to fix typos in f2fs files.
Signed-off-by: Jinyoung Choi <j-young.choi@samsung.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch tries to use bitfield in struct f2fs_io_info to improve
memory usage.
struct f2fs_io_info {
...
unsigned int need_lock:8; /* indicate we need to lock cp_rwsem */
unsigned int version:8; /* version of the node */
unsigned int submitted:1; /* indicate IO submission */
unsigned int in_list:1; /* indicate fio is in io_list */
unsigned int is_por:1; /* indicate IO is from recovery or not */
unsigned int retry:1; /* need to reallocate block address */
unsigned int encrypted:1; /* indicate file is encrypted */
unsigned int post_read:1; /* require post read */
...
};
After this patch, size of struct f2fs_io_info reduces from 136 to 120.
[Nathan: fix a compile warning (single-bit-bitfield-constant-conversion)]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Just open code the logic in the only caller, where it is more
obvious.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Remove __refresh_next_blkoff by opencoding the SSR vs LFS segment check
in the only caller, and then add helpers for SSR block selection and
blkoff randomization instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Just fold this trivial wrapper into the only caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Simplify the check whether to allocate a new segment or reuse an open
one.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Add a helper to return the valid blocks on log and SSR segments, and
replace the last two uses of curseg_blkoff with it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This function just assigns a summary entry. This can be done entirely
typesafe with an open code struct assignment that relies on array
indexing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs_issue_discard_timeout() returns whether discard cmds are dropped,
which does not match the meaning of the function. Let's change it to
return whether all discard cmd are issued.
After commit 4d67490498 ("f2fs: Don't create discard thread when
device doesn't support realtime discard"), f2fs_issue_discard_timeout()
is alse called by f2fs_remount(). Since the comments of
f2fs_issue_discard_timeout() doesn't make much sense, let's update it.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Otherwise, last .atomic_write_task will be remained in structure
f2fs_inode_info, resulting in aborting atomic_write accidentally
in race case. Meanwhile, clear original_i_size as well.
Fixes: 7a10f0177e ("f2fs: don't give partially written atomic data from process crash")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Commit 3db1de0e58 ("f2fs: change the current atomic write way")
removed old tracepoints, but it missed to add new one, this patch
fixes to introduce trace_f2fs_replace_atomic_write_block to trace
atomic_write commit flow.
Fixes: 3db1de0e58 ("f2fs: change the current atomic write way")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The current discard_io_aware_gran is a fixed value, change it to be
configurable through the sys node.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously, we supported to account iostat io_bytes,
in this patch, it adds to account iostat count and avg_bytes:
time: 1671648667
io_bytes count avg_bytes
[WRITE]
app buffered data: 31 2 15
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
discard_wake and gc_wake have only two values, 0 or 1.
So there is no need to use int type to store them.
BTW, move discard_wake to the end of the
discard_cmd_control structure.
Before:
- sizeof(struct discard_cmd_control): 8392
After move:
- sizeof(struct discard_cmd_control): 8384
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
There is no need to additionally use f2fs_show_injection_info()
to output information. Concatenate time_to_inject() and
__time_to_inject() via a macro. In the new __time_to_inject()
function, pass in the caller function name and parent function.
In this way, we no longer need the f2fs_show_injection_info() function,
and let's remove it.
Suggested-by: Chao Yu <chao@kernel.org>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Any of the following scenarios will send more than the number of
max_requests at a time, which will not meet the design of the
max_requests limit.
- Set max_ordered_discard larger than discard_granularity from userspace.
- It is a small size device, discard_granularity can be tuned to 1 in
f2fs_tuning_parameters().
We need to deliver the accumulated @issued to __issue_discard_cmd_orderly()
to meet the max_requests limit.
BTW, convert the parameter type of @issued in __submit_discard_cmd().
Signed-off-by: Yuwei Guan <Yuwei.Guan@zeekrlife.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
After below changes:
commit 14db0b3c7b ("fscrypt: stop using PG_error to track error status")
commit 98dc08bae6 ("fsverity: stop using PG_error to track error status")
There is no place in f2fs we will set PG_error flag in page, let's remove
other PG_error usage in f2fs, as a step towards freeing the PG_error flag
for other uses.
Cc: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
IS_F2FS_IPU_* macro can be used to identify whether
f2fs ipu related policies are enabled.
BTW, convert to use BIT() instead of open code.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
With below two cases, it will cause NULL pointer dereference when
accessing SM_I(sbi)->fcc_info in f2fs_issue_flush().
a) If kthread_run() fails in f2fs_create_flush_cmd_control(), it will
release SM_I(sbi)->fcc_info,
- mount -o noflush_merge /dev/vda /mnt/f2fs
- mount -o remount,flush_merge /dev/vda /mnt/f2fs -- kthread_run() fails
- dd if=/dev/zero of=/mnt/f2fs/file bs=4k count=1 conv=fsync
b) we will never allocate memory for SM_I(sbi)->fcc_info w/ below
testcase,
- mount -o ro /dev/vda /mnt/f2fs
- mount -o rw,remount /dev/vda /mnt/f2fs
- dd if=/dev/zero of=/mnt/f2fs/file bs=4k count=1 conv=fsync
In order to fix this issue, let change as below:
- fix error path handling in f2fs_create_flush_cmd_control().
- allocate SM_I(sbi)->fcc_info even if readonly is on.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this round, we've added two features: 1) F2FS_IOC_START_ATOMIC_REPLACE and
2) per-block age-based extent cache. 1) is a variant of the previous atomic
write feature which guarantees a per-file atomicity. It would be more efficient
than AtomicFile implementation in Android framework. 2) implements another type
of extent cache in memory which keeps the per-block age in a file, so that block
allocator could split the hot and cold data blocks more accurately.
Enhancement:
- introduce F2FS_IOC_START_ATOMIC_REPLACE
- refactor extent_cache to add a new per-block-age-based extent cache support
- introduce discard_urgent_util, gc_mode, max_ordered_discard sysfs knobs
- add proc entry to show discard_plist info
- optimize iteration over sparse directories
- add barrier mount option
Bug fix
- avoid victim selection from previous victim section
- fix to enable compress for newly created file if extension matches
- set zstd compress level correctly
- initialize locks early in f2fs_fill_super() to fix bugs reported by syzbot
- correct i_size change for atomic writes
- allow to read node block after shutdown
- allow to set compression for inlined file
- fix gc mode when gc_urgent_high_remaining is 1
- should put a page when checking the summary info
Minor fixes and various clean-ups in GC, discard, debugfs, sysfs, and doc.
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Merge tag 'f2fs-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've added two features: F2FS_IOC_START_ATOMIC_REPLACE
and a per-block age-based extent cache.
F2FS_IOC_START_ATOMIC_REPLACE is a variant of the previous atomic
write feature which guarantees a per-file atomicity. It would be more
efficient than AtomicFile implementation in Android framework.
The per-block age-based extent cache implements another type of extent
cache in memory which keeps the per-block age in a file, so that block
allocator could split the hot and cold data blocks more accurately.
Enhancements:
- introduce F2FS_IOC_START_ATOMIC_REPLACE
- refactor extent_cache to add a new per-block-age-based extent cache support
- introduce discard_urgent_util, gc_mode, max_ordered_discard sysfs knobs
- add proc entry to show discard_plist info
- optimize iteration over sparse directories
- add barrier mount option
Bug fixes:
- avoid victim selection from previous victim section
- fix to enable compress for newly created file if extension matches
- set zstd compress level correctly
- initialize locks early in f2fs_fill_super() to fix bugs reported by syzbot
- correct i_size change for atomic writes
- allow to read node block after shutdown
- allow to set compression for inlined file
- fix gc mode when gc_urgent_high_remaining is 1
- should put a page when checking the summary info
Minor fixes and various clean-ups in GC, discard, debugfs, sysfs, and
doc"
* tag 'f2fs-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (63 commits)
f2fs: reset wait_ms to default if any of the victims have been selected
f2fs: fix some format WARNING in debug.c and sysfs.c
f2fs: don't call f2fs_issue_discard_timeout() when discard_cmd_cnt is 0 in f2fs_put_super()
f2fs: fix iostat parameter for discard
f2fs: Fix spelling mistake in label: free_bio_enrty_cache -> free_bio_entry_cache
f2fs: add block_age-based extent cache
f2fs: allocate the extent_cache by default
f2fs: refactor extent_cache to support for read and more
f2fs: remove unnecessary __init_extent_tree
f2fs: move internal functions into extent_cache.c
f2fs: specify extent cache for read explicitly
f2fs: introduce f2fs_is_readonly() for readability
f2fs: remove F2FS_SET_FEATURE() and F2FS_CLEAR_FEATURE() macro
f2fs: do some cleanup for f2fs module init
MAINTAINERS: Add f2fs bug tracker link
f2fs: remove the unused flush argument to change_curseg
f2fs: open code allocate_segment_by_default
f2fs: remove struct segment_allocation default_salloc_ops
f2fs: introduce discard_urgent_util sysfs node
f2fs: define MIN_DISCARD_GRANULARITY macro
...
No need to call f2fs_issue_discard_timeout() in f2fs_put_super,
when no discard command requires issue. Since the caller of
f2fs_issue_discard_timeout() usually judges the number of discard
commands before using it. Let's move this logic to
f2fs_issue_discard_timeout().
By the way, use f2fs_realtime_discard_enable to simplify the code.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Just like other data we count uses the number of bytes as the basic unit,
but discard uses the number of cmds as the statistical unit. In fact the
discard command contains the number of blocks, so let's change to the
number of bytes as the base unit.
Fixes: b0af6d491a ("f2fs: add app/fs io stat")
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a runtime hot/cold data separation method
for f2fs, in order to improve the accuracy for data temperature
classification, reduce the garbage collection overhead after
long-term data updates.
Enhanced hot/cold data separation can record data block update
frequency as "age" of the extent per inode, and take use of the age
info to indicate better temperature type for data block allocation:
- It records total data blocks allocated since mount;
- When file extent has been updated, it calculate the count of data
blocks allocated since last update as the age of the extent;
- Before the data block allocated, it searches for the age info and
chooses the suitable segment for allocation.
Test and result:
- Prepare: create about 30000 files
* 3% for cold files (with cold file extension like .apk, from 3M to 10M)
* 50% for warm files (with random file extension like .FcDxq, from 1K
to 4M)
* 47% for hot files (with hot file extension like .db, from 1K to 256K)
- create(5%)/random update(90%)/delete(5%) the files
* total write amount is about 70G
* fsync will be called for .db files, and buffered write will be used
for other files
The storage of test device is large enough(128G) so that it will not
switch to SSR mode during the test.
Benefit: dirty segment count increment reduce about 14%
- before: Dirty +21110
- after: Dirty +18286
Signed-off-by: qixiaoyu1 <qixiaoyu1@xiaomi.com>
Signed-off-by: xiongping1 <xiongping1@xiaomi.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
allocate_segment_by_default has just two callers, which use very
different code pathes inside it based on the force paramter. Just
open code the logic in the two callers using a new helper to decided
if a new segment should be allocated.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
There is only single instance of these ops, so remove the indirection
and call allocate_segment_by_default directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Through this node, you can control the background discard
to run more aggressively or not aggressively when reach the
utilization rate of the space.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Do cleanup in f2fs_tuning_parameters() and __init_discard_policy(),
let's use macro instead of number.
Suggested-by: Chao Yu <chao@kernel.org>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Under the current logic, after the discard thread wakes up, it will not
run according to the expected policy, but will use the expected policy
before sleep. Move the strategy selection to after the thread wakes up,
so that the running state of the thread meets expectations.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Use f2fs_do_truncate_blocks() to truncate all blocks in-batch in
__complete_revoke_list().
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Since __queue_discard_cmd() never returns an error,
let's make it return void.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Complaint from Matthew Wilcox in another similar place:
"submit? You don't submit anything at the 'submit' label.
it should be called 'skip' or something. But I think this
is just badly written and you don't need a goto at all."
Let's remove submit label for readability.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
introduce a new ioctl to replace the whole content of a file atomically,
which means it induces truncate and content update at the same time.
We can start it with F2FS_IOC_START_ATOMIC_REPLACE and complete it with
F2FS_IOC_COMMIT_ATOMIC_WRITE. Or abort it with
F2FS_IOC_ABORT_ATOMIC_WRITE.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
These cases were done with this Coccinelle:
@@
expression H;
expression L;
@@
- (get_random_u32_below(H) + L)
+ get_random_u32_inclusive(L, H + L - 1)
@@
expression H;
expression L;
expression E;
@@
get_random_u32_inclusive(L,
H
- + E
- - E
)
@@
expression H;
expression L;
expression E;
@@
get_random_u32_inclusive(L,
H
- - E
- + E
)
@@
expression H;
expression L;
expression E;
expression F;
@@
get_random_u32_inclusive(L,
H
- - E
+ F
- + E
)
@@
expression H;
expression L;
expression E;
expression F;
@@
get_random_u32_inclusive(L,
H
- + E
+ F
- - E
)
And then subsequently cleaned up by hand, with several automatic cases
rejected if it didn't make sense contextually.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This is a simple mechanical transformation done by:
@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
(E)
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Reviewed-by: SeongJae Park <sj@kernel.org> # for damon
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
We need to make sure i_size doesn't change until atomic write commit is
successful and restore it when commit is failed.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Fix the following coccicheck warning:
./fs/f2fs/segment.c:877:24-25: WARNING opportunity for max()
Signed-off-by: KaiLong Wang <wangkailong@jari.cn>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The current max_ordered_discard is a fixed value, change it to be
configurable through the sys node.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In the DPOLICY_BG mode, there is a conflict between
the two conditions "i + 1 < dpolicy->granularity" and
"i < DEFAULT_DISCARD_GRANULARITY". If i = 15, the first
condition is false, it will enter the second condition
and dispatch all small granularity discards in function
__issue_discard_cmd_orderly. The restrictive effect
of the first condition to small discards will be
invalidated. These two conditions should align.
Fixes: 20ee438232 ("f2fs: issue small discard by LBA order")
Signed-off-by: Dongdong Zhang <zhangdongdong1@oppo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Just cleanup for readable, no functional changes.
Suggested-by: Chao Yu <chao@kernel.org>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:
@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)
@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@
- RAND = get_random_u32();
... when != RAND
- RAND %= (E);
+ RAND = prandom_u32_max(E);
// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@
((T)get_random_u32()@p & (LITERAL))
// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@
value = None
if literal.startswith('0x'):
value = int(literal, 16)
elif literal[0] in '123456789':
value = int(literal, 10)
if value is None:
print("I don't know how to handle %s" % (literal))
cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
print("Skipping 0x%x for cleanup elsewhere" % (value))
cocci.include_match(False)
elif value & (value + 1) != 0:
print("Skipping 0x%x because it's not a power of two minus one" % (value))
cocci.include_match(False)
elif literal.startswith('0x'):
coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))
// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@
- (FUNC()@p & (LITERAL))
+ prandom_u32_max(RESULT)
@collapse_ret@
type T;
identifier VAR;
expression E;
@@
{
- T VAR;
- VAR = (E);
- return VAR;
+ return E;
}
@drop_var@
type T;
identifier VAR;
@@
{
- T VAR;
... when != VAR
}
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
