| Age | Commit message (Collapse) | Author | Files | Lines |
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new_inode used to have the following:
spin_lock(&inode_lock);
inodes_stat.nr_inodes++;
list_add(&inode->i_list, &inode_in_use);
list_add(&inode->i_sb_list, &sb->s_inodes);
inode->i_ino = ++last_ino;
inode->i_state = 0;
spin_unlock(&inode_lock);
over time things disappeared, got moved around or got replaced (global
inode lock with a per-inode lock), eventually this got reduced to:
spin_lock(&inode->i_lock);
inode->i_state = 0;
spin_unlock(&inode->i_lock);
But the lock acquire here does not synchronize against anyone.
Additionally iget5_locked performs i_state = 0 assignment without any
locks to begin with, the two combined look confusing at best.
It looks like the current state is a leftover which was not cleaned up.
Ideally it would be an invariant that i_state == 0 to begin with, but
achieving that would require dealing with all filesystem alloc handlers
one by one.
In the meantime drop the misleading locking and move i_state zeroing to
inode_init_always so that others don't need to deal with it by hand.
Signed-off-by: Mateusz Guzik <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
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Add a pr_err warning in case a ctl_table is registered with a sentinel
element containing a NULL procname.
Signed-off-by: Joel Granados <[email protected]>
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Remove the mention of a "zero terminated entry" from the
__register_sysctl_table function doc.
Signed-off-by: Joel Granados <[email protected]>
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Erase the code comments mentioning "child" that were forgotten when the
child element was removed in commit 2f2665c13af48 ("sysctl: replace
child with an enumeration").
Signed-off-by: Joel Granados <[email protected]>
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Now that the sentinels have been removed from ctl_table arrays, there is
no need to artificially append empty ctl_table elements at ctl_table
registration. Remove superfluous empty allocation from new_dir and
new_links.
Signed-off-by: Joel Granados <[email protected]>
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The number of ctl_table entries (nr_entries) calculation was previously
based on the ctl_table_size and the sentinel element. Since the
sentinels have been removed, we remove the calculation and just use the
ctl_table_size from the ctl_table_header.
Signed-off-by: Joel Granados <[email protected]>
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Use ARRAY_SIZE exclusively by removing the check to ->procname in the
stopping criteria of the loops traversing ctl_table arrays. This commit
finalizes the removal of the sentinel elements at the end of ctl_table
arrays which reduces the build time size and run time memory bloat by
~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%[email protected]/)
Remove the entry->procname evaluation from the for loop stopping
criteria in sysctl and sysctl_net.
Signed-off-by: Joel Granados <[email protected]>
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Pull bcachefs fixes from Kent Overstreet:
- fix kworker explosion, due to calling submit_bio() (which can block)
from a multithreaded workqueue
- fix error handling in btree node scan
- forward compat fix: kill an old debug assert
- key cache shrinker fixes
This is a partial fix for stalls doing multithreaded creates - there
were various O(n^2) issues the key cache shrinker was hitting [1].
There's more work coming here; I'm working on a patch to delete the
key cache lock, which initial testing shows to be a pretty drastic
performance improvement
- assorted syzbot fixes
Link: https://lore.kernel.org/linux-bcachefs/CAGudoHGenxzk0ZqPXXi1_QDbfqQhGHu+wUwzyS6WmfkUZ1HiXA@mail.gmail.com/ [1]
* tag 'bcachefs-2024-06-12' of https://evilpiepirate.org/git/bcachefs:
bcachefs: Fix rcu_read_lock() leak in drop_extra_replicas
bcachefs: Add missing bch_inode_info.ei_flags init
bcachefs: Add missing synchronize_srcu_expedited() call when shutting down
bcachefs: Check for invalid bucket from bucket_gen(), gc_bucket()
bcachefs: Replace bucket_valid() asserts in bucket lookup with proper checks
bcachefs: Fix snapshot_create_lock lock ordering
bcachefs: Fix refcount leak in check_fix_ptrs()
bcachefs: Leave a buffer in the btree key cache to avoid lock thrashing
bcachefs: Fix reporting of freed objects from key cache shrinker
bcachefs: set sb->s_shrinker->seeks = 0
bcachefs: increase key cache shrinker batch size
bcachefs: Enable automatic shrinking for rhashtables
bcachefs: fix the display format for show-super
bcachefs: fix stack frame size in fsck.c
bcachefs: Delete incorrect BTREE_ID_NR assertion
bcachefs: Fix incorrect error handling found_btree_node_is_readable()
bcachefs: Split out btree_write_submit_wq
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The DLM rcom handling has a check that all exflags are the same for the
whole lockspace membership nodes. There are some flags that requires
such handling, however DLM_LSFL_SOFTIRQ does not require this handling
and it should be backwards compatibility with other lockspaces that does
not set this flag.
Fixes: f328a26eeb53 ("dlm: introduce DLM_LSFL_SOFTIRQ_SAFE")
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
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The last use of 'dlm_processed_nodes' was removed in
commit 1696c75f1864 ("fs: dlm: add send ack threshold and append acks to
msgs").
Remove it.
Signed-off-by: Dr. David Alan Gilbert <[email protected]>
Signed-off-by: David Teigland <[email protected]>
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The quota code is missing some locking between local quota changes and
syncing those quota changes to the global quota file (gfs2_quota_sync);
in particular, qd->qd_change needs to be kept in sync with the
QDF_CHANGE change flag and the number of references held. Use the
qd->qd_lockref.lock spinlock for that.
With the qd->qd_lockref.lock spinlock held, we can no longer call
lockref_get(), so turn qd_hold() into a variant that assumes that the
lock is held. This function is really supposed to take an additional
reference when one or more references are already held, so check for
that instead of checking if the lockref is dead.
Signed-off-by: Andreas Gruenbacher <[email protected]>
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Previously, kfunc declarations in bpf_kfuncs.h (and others) used "user
facing" types for kfuncs prototypes while the actual kfunc definitions
used "kernel facing" types. More specifically: bpf_dynptr vs
bpf_dynptr_kern, __sk_buff vs sk_buff, and xdp_md vs xdp_buff.
It wasn't an issue before, as the verifier allows aliased types.
However, since we are now generating kfunc prototypes in vmlinux.h (in
addition to keeping bpf_kfuncs.h around), this conflict creates
compilation errors.
Fix this conflict by using "user facing" types in kfunc definitions.
This results in more casts, but otherwise has no additional runtime
cost.
Note, similar to 5b268d1ebcdc ("bpf: Have bpf_rdonly_cast() take a const
pointer"), we also make kfuncs take const arguments where appropriate in
order to make the kfunc more permissive.
Signed-off-by: Daniel Xu <[email protected]>
Link: https://lore.kernel.org/r/b58346a63a0e66bc9b7504da751b526b0b189a67.1718207789.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <[email protected]>
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chenyuwen reports a f2fs bug as below:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000011
fscrypt_set_bio_crypt_ctx+0x78/0x1e8
f2fs_grab_read_bio+0x78/0x208
f2fs_submit_page_read+0x44/0x154
f2fs_get_read_data_page+0x288/0x5f4
f2fs_get_lock_data_page+0x60/0x190
truncate_partial_data_page+0x108/0x4fc
f2fs_do_truncate_blocks+0x344/0x5f0
f2fs_truncate_blocks+0x6c/0x134
f2fs_truncate+0xd8/0x200
f2fs_iget+0x20c/0x5ac
do_garbage_collect+0x5d0/0xf6c
f2fs_gc+0x22c/0x6a4
f2fs_disable_checkpoint+0xc8/0x310
f2fs_fill_super+0x14bc/0x1764
mount_bdev+0x1b4/0x21c
f2fs_mount+0x20/0x30
legacy_get_tree+0x50/0xbc
vfs_get_tree+0x5c/0x1b0
do_new_mount+0x298/0x4cc
path_mount+0x33c/0x5fc
__arm64_sys_mount+0xcc/0x15c
invoke_syscall+0x60/0x150
el0_svc_common+0xb8/0xf8
do_el0_svc+0x28/0xa0
el0_svc+0x24/0x84
el0t_64_sync_handler+0x88/0xec
It is because inode.i_crypt_info is not initialized during below path:
- mount
- f2fs_fill_super
- f2fs_disable_checkpoint
- f2fs_gc
- f2fs_iget
- f2fs_truncate
So, let's relocate truncation of preallocated blocks to f2fs_file_open(),
after fscrypt_file_open().
Fixes: d4dd19ec1ea0 ("f2fs: do not expose unwritten blocks to user by DIO")
Reported-by: chenyuwen <[email protected]>
Closes: https://lore.kernel.org/linux-kernel/[email protected]
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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syzbot reports a f2fs bug as below:
BUG: KASAN: slab-use-after-free in sanity_check_extent_cache+0x370/0x410 fs/f2fs/extent_cache.c:46
Read of size 4 at addr ffff8880739ab220 by task syz-executor200/5097
CPU: 0 PID: 5097 Comm: syz-executor200 Not tainted 6.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
sanity_check_extent_cache+0x370/0x410 fs/f2fs/extent_cache.c:46
do_read_inode fs/f2fs/inode.c:509 [inline]
f2fs_iget+0x33e1/0x46e0 fs/f2fs/inode.c:560
f2fs_nfs_get_inode+0x74/0x100 fs/f2fs/super.c:3237
generic_fh_to_dentry+0x9f/0xf0 fs/libfs.c:1413
exportfs_decode_fh_raw+0x152/0x5f0 fs/exportfs/expfs.c:444
exportfs_decode_fh+0x3c/0x80 fs/exportfs/expfs.c:584
do_handle_to_path fs/fhandle.c:155 [inline]
handle_to_path fs/fhandle.c:210 [inline]
do_handle_open+0x495/0x650 fs/fhandle.c:226
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
We missed to cover sanity_check_extent_cache() w/ extent cache lock,
so, below race case may happen, result in use after free issue.
- f2fs_iget
- do_read_inode
- f2fs_init_read_extent_tree
: add largest extent entry in to cache
- shrink
- f2fs_shrink_read_extent_tree
- __shrink_extent_tree
- __detach_extent_node
: drop largest extent entry
- sanity_check_extent_cache
: access et->largest w/o lock
let's refactor sanity_check_extent_cache() to avoid extent cache access
and call it before f2fs_init_read_extent_tree() to fix this issue.
Reported-by: [email protected]
Closes: https://lore.kernel.org/linux-f2fs-devel/[email protected]
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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If device is readonly, make f2fs_convert_inline_inode()
return EROFS instead of zero, otherwise it may trigger
panic during writeback of inline inode's dirty page as
below:
f2fs_write_single_data_page+0xbb6/0x1e90 fs/f2fs/data.c:2888
f2fs_write_cache_pages fs/f2fs/data.c:3187 [inline]
__f2fs_write_data_pages fs/f2fs/data.c:3342 [inline]
f2fs_write_data_pages+0x1efe/0x3a90 fs/f2fs/data.c:3369
do_writepages+0x359/0x870 mm/page-writeback.c:2634
filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:397
__filemap_fdatawrite_range mm/filemap.c:430 [inline]
file_write_and_wait_range+0x1aa/0x290 mm/filemap.c:788
f2fs_do_sync_file+0x68a/0x1ae0 fs/f2fs/file.c:276
generic_write_sync include/linux/fs.h:2806 [inline]
f2fs_file_write_iter+0x7bd/0x24e0 fs/f2fs/file.c:4977
call_write_iter include/linux/fs.h:2114 [inline]
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xa72/0xc90 fs/read_write.c:590
ksys_write+0x1a0/0x2c0 fs/read_write.c:643
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Cc: [email protected]
Reported-by: [email protected]
Closes: https://lore.kernel.org/linux-f2fs-devel/[email protected]
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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IOPRIO_PRIO_DATA in the new kernel version includes level and hint,
So Macro IOPRIO_PRIO_LEVEL is more accurate to get ckpt thread
ioprio data/level, and it is also consisten with the way setting
ckpt thread ioprio by IOPRIO_PRIO_VALUE(class, data/level).
Besides, change variable name from "data" to "level" for more readable.
Signed-off-by: Zhiguo Niu <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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syzbot reports f2fs bug as below:
kernel BUG at fs/f2fs/inode.c:933!
RIP: 0010:f2fs_evict_inode+0x1576/0x1590 fs/f2fs/inode.c:933
Call Trace:
evict+0x2a4/0x620 fs/inode.c:664
dispose_list fs/inode.c:697 [inline]
evict_inodes+0x5f8/0x690 fs/inode.c:747
generic_shutdown_super+0x9d/0x2c0 fs/super.c:675
kill_block_super+0x44/0x90 fs/super.c:1667
kill_f2fs_super+0x303/0x3b0 fs/f2fs/super.c:4894
deactivate_locked_super+0xc1/0x130 fs/super.c:484
cleanup_mnt+0x426/0x4c0 fs/namespace.c:1256
task_work_run+0x24a/0x300 kernel/task_work.c:180
ptrace_notify+0x2cd/0x380 kernel/signal.c:2399
ptrace_report_syscall include/linux/ptrace.h:411 [inline]
ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]
syscall_exit_work kernel/entry/common.c:251 [inline]
syscall_exit_to_user_mode_prepare kernel/entry/common.c:278 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
syscall_exit_to_user_mode+0x15c/0x280 kernel/entry/common.c:296
do_syscall_64+0x50/0x110 arch/x86/entry/common.c:88
entry_SYSCALL_64_after_hwframe+0x63/0x6b
The root cause is:
- do_sys_open
- f2fs_lookup
- __f2fs_find_entry
- f2fs_i_depth_write
- f2fs_mark_inode_dirty_sync
- f2fs_dirty_inode
- set_inode_flag(inode, FI_DIRTY_INODE)
- umount
- kill_f2fs_super
- kill_block_super
- generic_shutdown_super
- sync_filesystem
: sb is readonly, skip sync_filesystem()
- evict_inodes
- iput
- f2fs_evict_inode
- f2fs_bug_on(sbi, is_inode_flag_set(inode, FI_DIRTY_INODE))
: trigger kernel panic
When we try to repair i_current_depth in readonly filesystem, let's
skip dirty inode to avoid panic in later f2fs_evict_inode().
Cc: [email protected]
Reported-by: [email protected]
Closes: https://lore.kernel.org/linux-f2fs-devel/[email protected]
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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SSR allocate mode will be used when doing file defragment
if ATGC is working at the same time, that is because
set_page_private_gcing may make CURSEG_ALL_DATA_ATGC segment
type got in f2fs_allocate_data_block when defragment page
is writeback, which may cause file fragmentation is worse.
A file with 2 fragmentations is changed as following after defragment:
----------------file info-------------------
sensorsdata :
--------------------------------------------
dev [254:48]
ino [0x 3029 : 12329]
mode [0x 81b0 : 33200]
nlink [0x 1 : 1]
uid [0x 27e6 : 10214]
gid [0x 27e6 : 10214]
size [0x 242000 : 2367488]
blksize [0x 1000 : 4096]
blocks [0x 1210 : 4624]
--------------------------------------------
file_pos start_blk end_blk blks
0 11361121 11361207 87
356352 11361215 11361216 2
364544 11361218 11361218 1
368640 11361220 11361221 2
376832 11361224 11361225 2
385024 11361227 11361238 12
434176 11361240 11361252 13
487424 11361254 11361254 1
491520 11361271 11361279 9
528384 3681794 3681795 2
536576 3681797 3681797 1
540672 3681799 3681799 1
544768 3681803 3681803 1
548864 3681805 3681805 1
552960 3681807 3681807 1
557056 3681809 3681809 1
Signed-off-by: Zhiguo Niu <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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It will return all zero data when DIO reading from inline_data inode, it
is because f2fs_iomap_begin() assign iomap->type w/ IOMAP_HOLE incorrectly
for this case.
We can let iomap framework handle inline data via assigning iomap->type
and iomap->inline_data correctly, however, it will be a little bit
complicated when handling race case in between direct IO and buffered IO.
So, let's force to use buffered IO to fix this issue.
Cc: [email protected]
Reported-by: Barry Song <[email protected]>
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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Subsequent f2fs_stop_checkpoint will set cp_err, so this
SBI_NEED_FSCK flag set action is invalid.
Signed-off-by: Zhiguo Niu <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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If curseg is not the first segment in its zone, the zone is not empty.
A new section should be allocated and avoid resetting the old zone.
Reviewed-by: Chao Yu <[email protected]>
Signed-off-by: Sheng Yong <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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FS_IOC_GETFSSYSFSPATH ioctl expects sysfs sub-path of a filesystem, the
format can be "$FSTYP/$SYSFS_IDENTIFIER" under /sys/fs, it can helps to
standardizes exporting sysfs datas across filesystems.
This patch wires up FS_IOC_GETFSSYSFSPATH for f2fs, it will output
"f2fs/<dev>".
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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inode can be fuzzed, so it can has F2FS_INLINE_DATA flag and valid
i_blocks/i_nid value, this patch supports to do extra sanity check
to detect such corrupted state.
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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syzbot reports a f2fs bug as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/inline.c:258!
CPU: 1 PID: 34 Comm: kworker/u8:2 Not tainted 6.9.0-rc6-syzkaller-00012-g9e4bc4bcae01 #0
RIP: 0010:f2fs_write_inline_data+0x781/0x790 fs/f2fs/inline.c:258
Call Trace:
f2fs_write_single_data_page+0xb65/0x1d60 fs/f2fs/data.c:2834
f2fs_write_cache_pages fs/f2fs/data.c:3133 [inline]
__f2fs_write_data_pages fs/f2fs/data.c:3288 [inline]
f2fs_write_data_pages+0x1efe/0x3a90 fs/f2fs/data.c:3315
do_writepages+0x35b/0x870 mm/page-writeback.c:2612
__writeback_single_inode+0x165/0x10b0 fs/fs-writeback.c:1650
writeback_sb_inodes+0x905/0x1260 fs/fs-writeback.c:1941
wb_writeback+0x457/0xce0 fs/fs-writeback.c:2117
wb_do_writeback fs/fs-writeback.c:2264 [inline]
wb_workfn+0x410/0x1090 fs/fs-writeback.c:2304
process_one_work kernel/workqueue.c:3254 [inline]
process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3335
worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
kthread+0x2f2/0x390 kernel/kthread.c:388
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
The root cause is: inline_data inode can be fuzzed, so that there may
be valid blkaddr in its direct node, once f2fs triggers background GC
to migrate the block, it will hit f2fs_bug_on() during dirty page
writeback.
Let's add sanity check on F2FS_INLINE_DATA flag in inode during GC,
so that, it can forbid migrating inline_data inode's data block for
fixing.
Reported-by: [email protected]
Closes: https://lore.kernel.org/linux-f2fs-devel/[email protected]
Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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Instead of inventing a custom way to conditionally enable debugging,
just make use of pr_debug(), which also has dynamic debugging facilities
and is more likely known to someone who hunts a problem in the netfs
code. Also drop the module parameter netfs_debug which didn't have any
effect without further source changes. (The variable netfs_debug was
only used in #ifdef blocks for cpp vars that don't exist; Note that
CONFIG_NETFS_DEBUG isn't settable via kconfig, a variable with that name
never existed in the mainline and is probably just taken over (and
renamed) from similar custom debug logging implementations.)
Signed-off-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>
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This is in preparation for the routine starting to zero the field.
De facto coded by Dave Chinner, see:
https://lore.kernel.org/linux-fsdevel/[email protected]/
Signed-off-by: Mateusz Guzik <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>
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With 20 threads each walking a dedicated 1000 dirs * 1000 files
directory tree to stat(2) on a 32 core + 24GB ram vm:
before: 3.54s user 892.30s system 1966% cpu 45.549 total
after: 3.28s user 738.66s system 1955% cpu 37.932 total (-16.7%)
Benchmark can be found here: https://people.freebsd.org/~mjg/fstree.tgz
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Mateusz Guzik <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Acked-by: David Sterba <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
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This avoids one inode hash lock acquire in the common case on inode
creation, in effect significantly reducing contention.
On the stock kernel said lock is typically taken twice:
1. once to check if the inode happens to already be present
2. once to add it to the hash
The back-to-back lock/unlock pattern is known to degrade performance
significantly, which is further exacerbated if the hash is heavily
populated (long chains to walk, extending hold time). Arguably hash
sizing and hashing algo need to be revisited, but that's beyond the
scope of this patch.
With the acquire from step 1 eliminated with RCU lookup throughput
increases significantly at the scale of 20 cores (benchmark results at
the bottom).
So happens the hash already supports RCU-based operation, but lookups on
inode insertions didn't take advantage of it.
This of course has its limits as the global lock is still a bottleneck.
There was a patchset posted which introduced fine-grained locking[1] but
it appears staled. Apart from that doubt was expressed whether a
handrolled hash implementation is appropriate to begin with, suggesting
replacement with rhashtables. Nobody committed to carrying [1] across
the finish line or implementing anything better, thus the bandaid below.
iget_locked consumers (notably ext4) get away without any changes
because inode comparison method is built-in.
iget5_locked consumers pass a custom callback. Since removal of locking
adds more problems (inode can be changing) it's not safe to assume all
filesystems happen to cope. Thus iget5_locked_rcu gets added, requiring
manual conversion of interested filesystems.
In order to reduce code duplication find_inode and find_inode_fast grow
an argument indicating whether inode hash lock is held, which is passed
down in case sleeping is necessary. They always rcu_read_lock, which is
redundant but harmless. Doing it conditionally reduces readability for
no real gain that I can see. RCU-alike restrictions were already put on
callbacks due to the hash spinlock being held.
Benchmarking:
There is a real cache-busting workload scanning millions of files in
parallel (it's a backup appliance), where the initial lookup is
guaranteed to fail resulting in the two lock acquires on stock kernel
(and one with the patch at hand).
Implemented below is a synthetic benchmark providing the same behavior.
[I shall note the workload is not running on Linux, instead it was
causing trouble elsewhere. Benchmark below was used while addressing
said problems and was found to adequately represent the real workload.]
Total real time fluctuates by 1-2s.
With 20 threads each walking a dedicated 1000 dirs * 1000 files
directory tree to stat(2) on a 32 core + 24GB RAM vm:
ext4 (needed mkfs.ext4 -N 24000000):
before: 3.77s user 890.90s system 1939% cpu 46.118 total
after: 3.24s user 397.73s system 1858% cpu 21.581 total (-53%)
That's 20 million files to visit, while the machine can only cache about
15 million at a time (obtained from ext4_inode_cache object count in
/proc/slabinfo). Since each terminal inode is only visited once per run
this amounts to 0% hit ratio for the dentry cache and the hash table
(there are however hits for the intermediate directories).
On repeated runs the kernel caches the last ~15 mln, meaning there is ~5
mln of uncached inodes which are going to be visited first, evicting the
previously cached state as it happens.
Lack of hits can be trivially verified with bpftrace, like so:
bpftrace -e 'kretprobe:find_inode_fast { @[kstack(), retval != 0] = count(); }'\
-c "/bin/sh walktrees /testfs 20"
Best ran more than once.
Expected results after "warmup":
[snip]
@[
__ext4_iget+275
ext4_lookup+224
__lookup_slow+130
walk_component+219
link_path_walk.part.0.constprop.0+614
path_lookupat+62
filename_lookup+204
vfs_statx+128
vfs_fstatat+131
__do_sys_newfstatat+38
do_syscall_64+87
entry_SYSCALL_64_after_hwframe+118
, 1]: 20000
@[
__ext4_iget+275
ext4_lookup+224
__lookup_slow+130
walk_component+219
path_lookupat+106
filename_lookup+204
vfs_statx+128
vfs_fstatat+131
__do_sys_newfstatat+38
do_syscall_64+87
entry_SYSCALL_64_after_hwframe+118
, 1]: 20000000
That is 20 million calls for the initial lookup and 20 million after
allocating a new inode, all of them failing to return a value != 0
(i.e., they are returning NULL -- no match found).
Of course aborting the benchmark in the middle and starting it again (or
messing with the state in other ways) is going to alter these results.
Benchmark can be found here: https://people.freebsd.org/~mjg/fstree.tgz
[1] https://lore.kernel.org/all/[email protected]/
Signed-off-by: Mateusz Guzik <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
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Fix an issue where get_write is not used in smb2_set_ea().
Fixes: 6fc0a265e1b9 ("ksmbd: fix potential circular locking issue in smb2_set_ea()")
Cc: [email protected]
Reported-by: Wang Zhaolong <[email protected]>
Signed-off-by: Namjae Jeon <[email protected]>
Signed-off-by: Steve French <[email protected]>
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If the directory name in the root of the share starts with
character like 镜(0x955c) or Ṝ(0x1e5c), it (and anything inside)
cannot be accessed. The leading slash check must be checked after
converting unicode to nls string.
Cc: [email protected]
Signed-off-by: Namjae Jeon <[email protected]>
Signed-off-by: Steve French <[email protected]>
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Signed-off-by: Kent Overstreet <[email protected]>
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git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
"Misc:
- Restore debugfs behavior of ignoring unknown mount options
- Fix kernel doc for netfs_wait_for_oustanding_io()
- Fix struct statx comment after new addition for this cycle
- Fix a check in find_next_fd()
iomap:
- Fix data zeroing behavior when an extent spans the block that
contains i_size
- Restore i_size increasing in iomap_write_end() for now to avoid
stale data exposure on xfs with a realtime device
Cachefiles:
- Remove unneeded fdtable.h include
- Improve trace output for cachefiles_obj_{get,put}_ondemand_fd()
- Remove requests from the request list to prevent accessing already
freed requests
- Fix UAF when issuing restore command while the daemon is still
alive by adding an additional reference count to requests
- Fix UAF by grabbing a reference during xarray lookup with xa_lock()
held
- Simplify error handling in cachefiles_ondemand_daemon_read()
- Add consistency checks read and open requests to avoid crashes
- Add a spinlock to protect ondemand_id variable which is used to
determine whether an anonymous cachefiles fd has already been
closed
- Make on-demand reads killable allowing to handle broken cachefiles
daemon better
- Flush all requests after the kernel has been marked dead via
CACHEFILES_DEAD to avoid hung-tasks
- Ensure that closed requests are marked as such to avoid reusing
them with a reopen request
- Defer fd_install() until after copy_to_user() succeeded and thereby
get rid of having to use close_fd()
- Ensure that anonymous cachefiles on-demand fds are reused while
they are valid to avoid pinning already freed cookies"
* tag 'vfs-6.10-rc4.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
iomap: Fix iomap_adjust_read_range for plen calculation
iomap: keep on increasing i_size in iomap_write_end()
cachefiles: remove unneeded include of <linux/fdtable.h>
fs/file: fix the check in find_next_fd()
cachefiles: make on-demand read killable
cachefiles: flush all requests after setting CACHEFILES_DEAD
cachefiles: Set object to close if ondemand_id < 0 in copen
cachefiles: defer exposing anon_fd until after copy_to_user() succeeds
cachefiles: never get a new anonymous fd if ondemand_id is valid
cachefiles: add spin_lock for cachefiles_ondemand_info
cachefiles: add consistency check for copen/cread
cachefiles: remove err_put_fd label in cachefiles_ondemand_daemon_read()
cachefiles: fix slab-use-after-free in cachefiles_ondemand_daemon_read()
cachefiles: fix slab-use-after-free in cachefiles_ondemand_get_fd()
cachefiles: remove requests from xarray during flushing requests
cachefiles: add output string to cachefiles_obj_[get|put]_ondemand_fd
statx: Update offset commentary for struct statx
netfs: fix kernel doc for nets_wait_for_outstanding_io()
debugfs: continue to ignore unknown mount options
|
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When a lockspace user allows it, run callback functions directly from
softirq context, instead of queueing callbacks to be run from the
dlm_callback workqueue context.
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
|
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Introduce a new external lockspace flag DLM_LSFL_SOFTIRQ_SAFE. A
lockspace user will set this flag if it can handle dlm running the
callback functions from softirq context. When not set, dlm will
continue to run callback functions from the dlm_callback workqueue.
The new lockspace flag cannot be used for user space lockspaces, so
a uapi placeholder definition is used for the new flag value.
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
|
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The existing external lockspace flag DLM_LSFL_FS is now also
saved as an internal flag LSFL_FS, so it can be checked from
other code locations which want to know if a lockspace is
used from the kernel or user space.
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
|
|
Enable large folio support on zonefs.
Cc: Matthew Wilcox <[email protected]>
Cc: Damien Le Moal <[email protected]>
Signed-off-by: Johannes Thumshirn <[email protected]>
Reviewed-by: Bill O'Donnell <[email protected]>
Signed-off-by: Damien Le Moal <[email protected]>
|
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Signed-off-by: Kent Overstreet <[email protected]>
|
|
Use rcu to free rsb structs, and hold the rcu read lock
while looking up rsb structs. This allows us to avoid an
extra hash table lookup for an rsb. A new rsb flag HASHED
is added which is set while the rsb is in the hash table.
This flag is checked in place of repeating the hash table
lookup.
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
|
|
Remove a few calls to add_scan() and del_scan() in cases where
the rsb is a dir record, so the rsb should never be placed on
the scan list at all. Add WARN_ON to catch cases where this
is done.
Signed-off-by: David Teigland <[email protected]>
|
|
The old terminology of "toss" and "keep" is no longer an
accurate description of the rsb states and lists, so change
the names to "inactive" and "active". The old names had
also been copied into the scanning code, which is changed
back to use the "scan" name.
- "active" rsb structs have lkb's attached, and are ref counted.
- "inactive" rsb structs have no lkb's attached, are not ref counted.
- "scan" list is for rsb's that can be freed after a timeout period.
- "slow" lists are for infrequent iterations through active or
inactive rsb structs.
- inactive rsb structs that are directory records will not be put
on the scan list, since they are not freed based on timeouts.
- inactive rsb structs that are not directory records will be
put on the scan list to be freed, since they are not longer needed.
Signed-off-by: David Teigland <[email protected]>
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We use the polling interface to srcu for tracking pending frees; when
shutting down we don't need to wait for an srcu barrier to free them,
but SRCU still gets confused if we shutdown with an outstanding grace
period.
Reported-by: [email protected]
Reported-by: [email protected]
Signed-off-by: Kent Overstreet <[email protected]>
|
|
Turn more asserts into proper recoverable error paths.
Reported-by: [email protected]
Signed-off-by: Kent Overstreet <[email protected]>
|
|
The bucket_gens array and gc_buckets array known their own size; we
should be using those members, and returning an error.
Signed-off-by: Kent Overstreet <[email protected]>
|
|
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc2-ktest-00018-gebd1d148b278 #144 Not tainted
------------------------------------------------------
fio/1345 is trying to acquire lock:
ffff88813e200ab8 (&c->snapshot_create_lock){++++}-{3:3}, at: bch2_truncate+0x76/0xf0
but task is already holding lock:
ffff888105a1fa38 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: do_truncate+0x7b/0xc0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}:
down_write+0x3d/0xd0
bch2_write_iter+0x1c0/0x10f0
vfs_write+0x24a/0x560
__x64_sys_pwrite64+0x77/0xb0
x64_sys_call+0x17e5/0x1ab0
do_syscall_64+0x68/0x130
entry_SYSCALL_64_after_hwframe+0x4b/0x53
-> #1 (sb_writers#10){.+.+}-{0:0}:
mnt_want_write+0x4a/0x1d0
filename_create+0x69/0x1a0
user_path_create+0x38/0x50
bch2_fs_file_ioctl+0x315/0xbf0
__x64_sys_ioctl+0x297/0xaf0
x64_sys_call+0x10cb/0x1ab0
do_syscall_64+0x68/0x130
entry_SYSCALL_64_after_hwframe+0x4b/0x53
-> #0 (&c->snapshot_create_lock){++++}-{3:3}:
__lock_acquire+0x1445/0x25b0
lock_acquire+0xbd/0x2b0
down_read+0x40/0x180
bch2_truncate+0x76/0xf0
bchfs_truncate+0x240/0x3f0
bch2_setattr+0x7b/0xb0
notify_change+0x322/0x4b0
do_truncate+0x8b/0xc0
do_ftruncate+0x110/0x270
__x64_sys_ftruncate+0x43/0x80
x64_sys_call+0x1373/0x1ab0
do_syscall_64+0x68/0x130
entry_SYSCALL_64_after_hwframe+0x4b/0x53
other info that might help us debug this:
Chain exists of:
&c->snapshot_create_lock --> sb_writers#10 --> &sb->s_type->i_mutex_key#13
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sb->s_type->i_mutex_key#13);
lock(sb_writers#10);
lock(&sb->s_type->i_mutex_key#13);
rlock(&c->snapshot_create_lock);
*** DEADLOCK ***
Signed-off-by: Kent Overstreet <[email protected]>
|
|
fsck_err() does a goto fsck_err on error; factor out check_fix_ptr() so
that our error label can drop our device ref.
Signed-off-by: Kent Overstreet <[email protected]>
|
|
Signed-off-by: Kent Overstreet <[email protected]>
|
|
We count objects as freed when we move them to the srcu-pending lists
because we're doing the equivalent of a kfree_srcu(); the only
difference is managing the pending list ourself means we can allocate
from the pending list.
Signed-off-by: Kent Overstreet <[email protected]>
|
|
inodes and dentries are still present in the btree node cache, in much
more compact form
Signed-off-by: Kent Overstreet <[email protected]>
|
|
Signed-off-by: Kent Overstreet <[email protected]>
|
|
Since the key cache shrinker walks the rhashtable, a mostly empty
rhashtable leads to really nasty reclaim performance issues.
Signed-off-by: Kent Overstreet <[email protected]>
|