In this cycle, we mainly fixed some corner cases that manipulate a per-file
compression flag inappropriately. And, we found f2fs counted valid blocks in a
section incorrectly when zone capacity is set, and thus, fixed it with
additional sysfs entry to check it easily. Lastly, this series includes
several patches with respect to the new atomic write support such as a
couple of bug fixes and re-adding atomic_write_abort support that we removed
by mistake in the previous release.
Enhancement:
- add sysfs entries to understand atomic write operations and zone
capacity
- introduce memory mode to get a hint for low-memory devices
- adjust the waiting time of foreground GC
- decompress clusters under softirq to avoid non-deterministic latency
- do not skip updating inode when retrying to flush node page
- enforce single zone capacity
Bug fix:
- set the compression/no-compression flags correctly
- revive F2FS_IOC_ABORT_VOLATILE_WRITE
- check inline_data during compressed inode conversion
- understand zone capacity when calculating valid block count
As usual, the series includes several minor clean-ups and sanity checks.
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Merge tag 'f2fs-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this cycle, we mainly fixed some corner cases that manipulate a
per-file compression flag inappropriately. And, we found f2fs counted
valid blocks in a section incorrectly when zone capacity is set, and
thus, fixed it with additional sysfs entry to check it easily.
Lastly, this series includes several patches with respect to the new
atomic write support such as a couple of bug fixes and re-adding
atomic_write_abort support that we removed by mistake in the previous
release.
Enhancements:
- add sysfs entries to understand atomic write operations and zone
capacity
- introduce memory mode to get a hint for low-memory devices
- adjust the waiting time of foreground GC
- decompress clusters under softirq to avoid non-deterministic
latency
- do not skip updating inode when retrying to flush node page
- enforce single zone capacity
Bug fixes:
- set the compression/no-compression flags correctly
- revive F2FS_IOC_ABORT_VOLATILE_WRITE
- check inline_data during compressed inode conversion
- understand zone capacity when calculating valid block count
As usual, the series includes several minor clean-ups and sanity
checks"
* tag 'f2fs-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits)
f2fs: use onstack pages instead of pvec
f2fs: intorduce f2fs_all_cluster_page_ready
f2fs: clean up f2fs_abort_atomic_write()
f2fs: handle decompress only post processing in softirq
f2fs: do not allow to decompress files have FI_COMPRESS_RELEASED
f2fs: do not set compression bit if kernel doesn't support
f2fs: remove device type check for direct IO
f2fs: fix null-ptr-deref in f2fs_get_dnode_of_data
f2fs: revive F2FS_IOC_ABORT_VOLATILE_WRITE
f2fs: fix to do sanity check on segment type in build_sit_entries()
f2fs: obsolete unused MAX_DISCARD_BLOCKS
f2fs: fix to avoid use f2fs_bug_on() in f2fs_new_node_page()
f2fs: fix to remove F2FS_COMPR_FL and tag F2FS_NOCOMP_FL at the same time
f2fs: introduce sysfs atomic write statistics
f2fs: don't bother wait_ms by foreground gc
f2fs: invalidate meta pages only for post_read required inode
f2fs: allow compression of files without blocks
f2fs: fix to check inline_data during compressed inode conversion
f2fs: Delete f2fs_copy_page() and replace with memcpy_page()
f2fs: fix to invalidate META_MAPPING before DIO write
...
- Fix an accounting bug that made NR_FILE_DIRTY grow without limit
when running xfstests
- Convert more of mpage to use folios
- Remove add_to_page_cache() and add_to_page_cache_locked()
- Convert find_get_pages_range() to filemap_get_folios()
- Improvements to the read_cache_page() family of functions
- Remove a few unnecessary checks of PageError
- Some straightforward filesystem conversions to use folios
- Split PageMovable users out from address_space_operations into their
own movable_operations
- Convert aops->migratepage to aops->migrate_folio
- Remove nobh support (Christoph Hellwig)
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Merge tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecache
Pull folio updates from Matthew Wilcox:
- Fix an accounting bug that made NR_FILE_DIRTY grow without limit
when running xfstests
- Convert more of mpage to use folios
- Remove add_to_page_cache() and add_to_page_cache_locked()
- Convert find_get_pages_range() to filemap_get_folios()
- Improvements to the read_cache_page() family of functions
- Remove a few unnecessary checks of PageError
- Some straightforward filesystem conversions to use folios
- Split PageMovable users out from address_space_operations into
their own movable_operations
- Convert aops->migratepage to aops->migrate_folio
- Remove nobh support (Christoph Hellwig)
* tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecache: (78 commits)
fs: remove the NULL get_block case in mpage_writepages
fs: don't call ->writepage from __mpage_writepage
fs: remove the nobh helpers
jfs: stop using the nobh helper
ext2: remove nobh support
ntfs3: refactor ntfs_writepages
mm/folio-compat: Remove migration compatibility functions
fs: Remove aops->migratepage()
secretmem: Convert to migrate_folio
hugetlb: Convert to migrate_folio
aio: Convert to migrate_folio
f2fs: Convert to filemap_migrate_folio()
ubifs: Convert to filemap_migrate_folio()
btrfs: Convert btrfs_migratepage to migrate_folio
mm/migrate: Add filemap_migrate_folio()
mm/migrate: Convert migrate_page() to migrate_folio()
nfs: Convert to migrate_folio
btrfs: Convert btree_migratepage to migrate_folio
mm/migrate: Convert expected_page_refs() to folio_expected_refs()
mm/migrate: Convert buffer_migrate_page() to buffer_migrate_folio()
...
As Dipanjan Das <mail.dipanjan.das@gmail.com> reported, syzkaller
found a f2fs bug as below:
RIP: 0010:f2fs_new_node_page+0x19ac/0x1fc0 fs/f2fs/node.c:1295
Call Trace:
write_all_xattrs fs/f2fs/xattr.c:487 [inline]
__f2fs_setxattr+0xe76/0x2e10 fs/f2fs/xattr.c:743
f2fs_setxattr+0x233/0xab0 fs/f2fs/xattr.c:790
f2fs_xattr_generic_set+0x133/0x170 fs/f2fs/xattr.c:86
__vfs_setxattr+0x115/0x180 fs/xattr.c:182
__vfs_setxattr_noperm+0x125/0x5f0 fs/xattr.c:216
__vfs_setxattr_locked+0x1cf/0x260 fs/xattr.c:277
vfs_setxattr+0x13f/0x330 fs/xattr.c:303
setxattr+0x146/0x160 fs/xattr.c:611
path_setxattr+0x1a7/0x1d0 fs/xattr.c:630
__do_sys_lsetxattr fs/xattr.c:653 [inline]
__se_sys_lsetxattr fs/xattr.c:649 [inline]
__x64_sys_lsetxattr+0xbd/0x150 fs/xattr.c:649
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
NAT entry and nat bitmap can be inconsistent, e.g. one nid is free
in nat bitmap, and blkaddr in its NAT entry is not NULL_ADDR, it
may trigger BUG_ON() in f2fs_new_node_page(), fix it.
Reported-by: Dipanjan Das <mail.dipanjan.das@gmail.com>
Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Improve static type checking by using the enum req_op type for variables
that represent a request operation and the new blk_opf_t type for
variables that represent request flags.
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-53-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Let's try to flush dirty inode again to improve subtle i_blocks mismatch.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Otherwise, we can get a wrong cp_error mark.
Cc: <stable@vger.kernel.org>
Fixes: a7b8618aa2 ("f2fs: avoid infinite loop to flush node pages")
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this round, we've refactored the existing atomic write support implemented
by in-memory operations to have storing data in disk temporarily, which can give
us a benefit to accept more atomic writes. At the same time, we removed the
existing volatile write support. We've also revisited the file pinning and GC
flows and found some corner cases which contributeed abnormal system behaviours.
As usual, there're several minor code refactoring for readability, sanity check,
and clean ups.
Enhancement
- allow compression for mmap files in compress_mode=user
- kill volatile write support
- change the current atomic write way
- give priority to select unpinned section for foreground GC
- introduce data read/write showing path info
- remove unnecessary f2fs_lock_op in f2fs_new_inode
Bug fix
- fix the file pinning flow during checkpoint=disable and GCs
- fix foreground and background GCs to select the right victims and get free
sections on time
- fix GC flags on defragmenting pages
- avoid an infinite loop to flush node pages
- fix fallocate to use file_modified to update permissions consistently
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Merge tag 'f2fs-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've refactored the existing atomic write support
implemented by in-memory operations to have storing data in disk
temporarily, which can give us a benefit to accept more atomic writes.
At the same time, we removed the existing volatile write support.
We've also revisited the file pinning and GC flows and found some
corner cases which contributeed abnormal system behaviours.
As usual, there're several minor code refactoring for readability,
sanity check, and clean ups.
Enhancements:
- allow compression for mmap files in compress_mode=user
- kill volatile write support
- change the current atomic write way
- give priority to select unpinned section for foreground GC
- introduce data read/write showing path info
- remove unnecessary f2fs_lock_op in f2fs_new_inode
Bug fixes:
- fix the file pinning flow during checkpoint=disable and GCs
- fix foreground and background GCs to select the right victims and
get free sections on time
- fix GC flags on defragmenting pages
- avoid an infinite loop to flush node pages
- fix fallocate to use file_modified to update permissions
consistently"
* tag 'f2fs-for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (40 commits)
f2fs: fix to tag gcing flag on page during file defragment
f2fs: replace F2FS_I(inode) and sbi by the local variable
f2fs: add f2fs_init_write_merge_io function
f2fs: avoid unneeded error handling for revoke_entry_slab allocation
f2fs: allow compression for mmap files in compress_mode=user
f2fs: fix typo in comment
f2fs: make f2fs_read_inline_data() more readable
f2fs: fix to do sanity check for inline inode
f2fs: fix fallocate to use file_modified to update permissions consistently
f2fs: don't use casefolded comparison for "." and ".."
f2fs: do not stop GC when requiring a free section
f2fs: keep wait_ms if EAGAIN happens
f2fs: introduce f2fs_gc_control to consolidate f2fs_gc parameters
f2fs: reject test_dummy_encryption when !CONFIG_FS_ENCRYPTION
f2fs: kill volatile write support
f2fs: change the current atomic write way
f2fs: don't need inode lock for system hidden quota
f2fs: stop allocating pinned sections if EAGAIN happens
f2fs: skip GC if possible when checkpoint disabling
f2fs: give priority to select unpinned section for foreground GC
...
Current atomic write has three major issues like below.
- keeps the updates in non-reclaimable memory space and they are even
hard to be migrated, which is not good for contiguous memory
allocation.
- disk spaces used for atomic files cannot be garbage collected, so
this makes it difficult for the filesystem to be defragmented.
- If atomic write operations hit the threshold of either memory usage
or garbage collection failure count, All the atomic write operations
will fail immediately.
To resolve the issues, I will keep a COW inode internally for all the
updates to be flushed from memory, when we need to flush them out in a
situation like high memory pressure. These COW inodes will be tagged
as orphan inodes to be reclaimed in case of sudden power-cut or system
failure during atomic writes.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
While converting f2fs_release_page() to f2fs_release_folio(), cache the
sb_info so we don't need to retrieve it twice, and remove the redundant
call to set_page_private(). The use of folios should be pushed further
into f2fs from here.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
The block layer for zoned disk can reorder the FUA'ed IOs. Let's use flush
command to keep the write order.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
It's slightly more efficient to go directly from the mapping to the
superblock than to go from the page. Now that these routines have
the mapping passed to them, there's no reason not to use it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Primarily this series converts some of the address_space operations
to take a folio instead of a page.
->is_partially_uptodate() takes a folio instead of a page and changes the
type of the 'from' and 'count' arguments to make it obvious they're bytes.
->invalidatepage() becomes ->invalidate_folio() and has a similar type change.
->launder_page() becomes ->launder_folio()
->set_page_dirty() becomes ->dirty_folio() and adds the address_space as
an argument.
There are a couple of other misc changes up front that weren't worth
separating into their own pull request.
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Merge tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache
Pull filesystem folio updates from Matthew Wilcox:
"Primarily this series converts some of the address_space operations to
take a folio instead of a page.
Notably:
- a_ops->is_partially_uptodate() takes a folio instead of a page and
changes the type of the 'from' and 'count' arguments to make it
obvious they're bytes.
- a_ops->invalidatepage() becomes ->invalidate_folio() and has a
similar type change.
- a_ops->launder_page() becomes ->launder_folio()
- a_ops->set_page_dirty() becomes ->dirty_folio() and adds the
address_space as an argument.
There are a couple of other misc changes up front that weren't worth
separating into their own pull request"
* tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits)
fs: Remove aops ->set_page_dirty
fb_defio: Use noop_dirty_folio()
fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio
fs: Convert __set_page_dirty_buffers to block_dirty_folio
nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio()
mm: Convert swap_set_page_dirty() to swap_dirty_folio()
ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio
f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio
f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio
f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio
afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio()
btrfs: Convert extent_range_redirty_for_io() to use folios
fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio
btrfs: Convert from set_page_dirty to dirty_folio
fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()
fs: Add aops->dirty_folio
fs: Remove aops->launder_page
orangefs: Convert launder_page to launder_folio
nfs: Convert from launder_page to launder_folio
fuse: Convert from launder_page to launder_folio
...
Removes a call to __set_page_dirty_nobuffers().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
This is a minimal change which just accepts the new arguments and passes
the single struct page to the functions which do the work. There is
very little progress here toards making f2fs support large folios.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
Quoted from Jing Xia's report, there is a potential deadlock may happen
between kworker and checkpoint as below:
[T:writeback] [T:checkpoint]
- wb_writeback
- blk_start_plug
bio contains NodeA was plugged in writeback threads
- do_writepages -- sync write inodeB, inc wb_sync_req[DATA]
- f2fs_write_data_pages
- f2fs_write_single_data_page -- write last dirty page
- f2fs_do_write_data_page
- set_page_writeback -- clear page dirty flag and
PAGECACHE_TAG_DIRTY tag in radix tree
- f2fs_outplace_write_data
- f2fs_update_data_blkaddr
- f2fs_wait_on_page_writeback -- wait NodeA to writeback here
- inode_dec_dirty_pages
- writeback_sb_inodes
- writeback_single_inode
- do_writepages
- f2fs_write_data_pages -- skip writepages due to wb_sync_req[DATA]
- wbc->pages_skipped += get_dirty_pages() -- PAGECACHE_TAG_DIRTY is not set but get_dirty_pages() returns one
- requeue_inode -- requeue inode to wb->b_dirty queue due to non-zero.pages_skipped
- blk_finish_plug
Let's try to avoid deadlock condition by forcing unplugging previous bio via
blk_finish_plug(current->plug) once we'v skipped writeback in writepages()
due to valid sbi->wb_sync_req[DATA/NODE].
Fixes: 687de7f101 ("f2fs: avoid IO split due to mixed WB_SYNC_ALL and WB_SYNC_NONE")
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Jing Xia <jing.xia@unisoc.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This adds a sysfs entry to call checkpoint during fsync() in order to avoid
long elapsed time to run roll-forward recovery when booting the device.
Default value doesn't enforce the limitation which is same as before.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs rw_semaphores work better if writers can starve readers,
especially for the checkpoint thread, because writers are strictly
more important than reader threads. This prevents significant priority
inversion between low-priority readers that blocked while trying to
acquire the read lock and a second acquisition of the write lock that
might be blocking high priority work.
Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this round, we've tried to address some performance issues in f2fs_checkpoint
and direct IO flows. Also, there was a work to enhance the page cache management
used for compression. Other than them, we've done typical work including sysfs,
code clean-ups, tracepoint, sanity check, in addition to bug fixes on corner
cases.
Enhancement:
- use iomap for direct IO
- try to avoid lock contention to improve f2fs_ckpt speed
- avoid unnecessary memory allocation in compression flow
- POSIX_FADV_DONTNEED drops the page cache containing compression pages
- add some sysfs entries (gc_urgent_high_remaining, pending_discard)
Bug fix:
- try not to expose unwritten blocks to user by DIO
: this was added to avoid merge conflict; another patch is coming to address
other missing case.
- relax minor error condition for file pinning feature used in Android OTA
- fix potential deadlock case in compression flow
- should not truncate any block on pinned file
In addition, we've done some code clean-ups and tracepoint/sanity check
improvement.
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Merge tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've tried to address some performance issues in
f2fs_checkpoint and direct IO flows. Also, there was a work to enhance
the page cache management used for compression. Other than them, we've
done typical work including sysfs, code clean-ups, tracepoint, sanity
check, in addition to bug fixes on corner cases.
Enhancements:
- use iomap for direct IO
- try to avoid lock contention to improve f2fs_ckpt speed
- avoid unnecessary memory allocation in compression flow
- POSIX_FADV_DONTNEED drops the page cache containing compression
pages
- add some sysfs entries (gc_urgent_high_remaining, pending_discard)
Bug fixes:
- try not to expose unwritten blocks to user by DIO (this was added
to avoid merge conflict; another patch is coming to address other
missing case)
- relax minor error condition for file pinning feature used in
Android OTA
- fix potential deadlock case in compression flow
- should not truncate any block on pinned file
In addition, we've done some code clean-ups and tracepoint/sanity
check improvement"
* tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits)
f2fs: do not allow partial truncation on pinned file
f2fs: remove redunant invalidate compress pages
f2fs: Simplify bool conversion
f2fs: don't drop compressed page cache in .{invalidate,release}page
f2fs: fix to reserve space for IO align feature
f2fs: fix to check available space of CP area correctly in update_ckpt_flags()
f2fs: support fault injection to f2fs_trylock_op()
f2fs: clean up __find_inline_xattr() with __find_xattr()
f2fs: fix to do sanity check on last xattr entry in __f2fs_setxattr()
f2fs: do not bother checkpoint by f2fs_get_node_info
f2fs: avoid down_write on nat_tree_lock during checkpoint
f2fs: compress: fix potential deadlock of compress file
f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file
f2fs: add gc_urgent_high_remaining sysfs node
f2fs: fix to do sanity check in is_alive()
f2fs: fix to avoid panic in is_alive() if metadata is inconsistent
f2fs: fix to do sanity check on inode type during garbage collection
f2fs: avoid duplicate call of mark_inode_dirty
f2fs: show number of pending discard commands
f2fs: support POSIX_FADV_DONTNEED drop compressed page cache
...
Various places in the kernel - largely in filesystems - respond to a
memory allocation failure by looping around and re-trying. Some of
these cannot conveniently use __GFP_NOFAIL, for reasons such as:
- a GFP_ATOMIC allocation, which __GFP_NOFAIL doesn't work on
- a need to check for the process being signalled between failures
- the possibility that other recovery actions could be performed
- the allocation is quite deep in support code, and passing down an
extra flag to say if __GFP_NOFAIL is wanted would be clumsy.
Many of these currently use congestion_wait() which (in almost all
cases) simply waits the given timeout - congestion isn't tracked for
most devices.
It isn't clear what the best delay is for loops, but it is clear that
the various filesystems shouldn't be responsible for choosing a timeout.
This patch introduces memalloc_retry_wait() with takes on that
responsibility. Code that wants to retry a memory allocation can call
this function passing the GFP flags that were used. It will wait
however is appropriate.
For now, it only considers __GFP_NORETRY and whatever
gfpflags_allow_blocking() tests. If blocking is allowed without
__GFP_NORETRY, then alloc_page either made some reclaim progress, or
waited for a while, before failing. So there is no need for much
further waiting. memalloc_retry_wait() will wait until the current
jiffie ends. If this condition is not met, then alloc_page() won't have
waited much if at all. In that case memalloc_retry_wait() waits about
200ms. This is the delay that most current loops uses.
linux/sched/mm.h needs to be included in some files now,
but linux/backing-dev.h does not.
Link: https://lkml.kernel.org/r/163754371968.13692.1277530886009912421@noble.neil.brown.name
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch tries to mitigate lock contention between f2fs_write_checkpoint and
f2fs_get_node_info along with nat_tree_lock.
The idea is, if checkpoint is currently running, other threads that try to grab
nat_tree_lock would be better to wait for checkpoint.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Inconsistent node block will cause a file fail to open or read,
which could make the user process crashes or stucks. Let's mark
SBI_NEED_FSCK flag to trigger a fix at next fsck time. After
unlinking the corrupted file, the user process could regenerate
a new one and work correctly.
Signed-off-by: Weichao Guo <guoweichao@oppo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If all free_nat_bitmap are available, we can rebuild nat_bits from
free_nat_bitmap entirely during umount, let's make another chance
to reenable nat_bits for image.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Added F2FS_IOSTAT config option to support getting IO statistics through
sysfs and printing out periodic IO statistics tracepoint events and
moved I/O statistics related codes into separate files for better
maintenance.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
[Jaegeuk Kim: set default=y]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch supports to inject fault into f2fs_kmem_cache_alloc().
Usage:
a) echo 32768 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=32768 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Compressed inode may suffer read performance issue due to it can not
use extent cache, so I propose to add this unaligned extent support
to improve it.
Currently, it only works in readonly format f2fs image.
Unaligned extent: in one compressed cluster, physical block number
will be less than logical block number, so we add an extra physical
block length in extent info in order to indicate such extent status.
The idea is if one whole cluster blocks are contiguous physically,
once its mapping info was readed at first time, we will cache an
unaligned (or aligned) extent info entry in extent cache, it expects
that the mapping info will be hitted when rereading cluster.
Merge policy:
- Aligned extents can be merged.
- Aligned extent and unaligned extent can not be merged.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
After the below patch, give cp is errored, we drop dirty node pages. This
can give NEW_ADDR to read node pages. Don't do WARN_ON() which gives
generic/475 failure.
Fixes: 28607bf3aa ("f2fs: drop dirty node pages when cp is in error status")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This tries to fix priority inversion in the below condition resulting in
long checkpoint delay.
f2fs_get_node_info()
- nat_tree_lock
-> sleep to grab journal_rwsem by contention
checkpoint
- waiting for nat_tree_lock
In order to let checkpoint go, let's release nat_tree_lock, if there's a
journal_rwsem contention.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Otherwise, writeback is going to fall in a loop to flush dirty inode forever
before getting SBI_CLOSING.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Support to use address space of inner inode to cache compressed block,
in order to improve cache hit ratio of random read.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Restruct f2fs page private layout for below reasons:
There are some cases that f2fs wants to set a flag in a page to
indicate a specified status of page:
a) page is in transaction list for atomic write
b) page contains dummy data for aligned write
c) page is migrating for GC
d) page contains inline data for inline inode flush
e) page belongs to merkle tree, and is verified for fsverity
f) page is dirty and has filesystem/inode reference count for writeback
g) page is temporary and has decompress io context reference for compression
There are existed places in page structure we can use to store
f2fs private status/data:
- page.flags: PG_checked, PG_private
- page.private
However it was a mess when we using them, which may cause potential
confliction:
page.private PG_private PG_checked page._refcount (+1 at most)
a) -1 set +1
b) -2 set
c), d), e) set
f) 0 set +1
g) pointer set
The other problem is page.flags has no free slot, if we can avoid set
zero to page.private and set PG_private flag, then we use non-zero value
to indicate PG_private status, so that we may have chance to reclaim
PG_private slot for other usage. [1]
The other concern is f2fs has bad scalability in aspect of indicating
more page status.
So in this patch, let's restructure f2fs' page.private as below to
solve above issues:
Layout A: lowest bit should be 1
| bit0 = 1 | bit1 | bit2 | ... | bit MAX | private data .... |
bit 0 PAGE_PRIVATE_NOT_POINTER
bit 1 PAGE_PRIVATE_ATOMIC_WRITE
bit 2 PAGE_PRIVATE_DUMMY_WRITE
bit 3 PAGE_PRIVATE_ONGOING_MIGRATION
bit 4 PAGE_PRIVATE_INLINE_INODE
bit 5 PAGE_PRIVATE_REF_RESOURCE
bit 6- f2fs private data
Layout B: lowest bit should be 0
page.private is a wrapped pointer.
After the change:
page.private PG_private PG_checked page._refcount (+1 at most)
a) 11 set +1
b) 101 set +1
c) 1001 set +1
d) 10001 set +1
e) set
f) 100001 set +1
g) pointer set +1
[1] https://lore.kernel.org/linux-f2fs-devel/20210422154705.GO3596236@casper.infradead.org/T/#u
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch combined the below three clean-up patches.
- modify open brace '{' following function definitions
- ERROR: spaces required around that ':'
- ERROR: spaces required before the open parenthesis '('
- ERROR: spaces prohibited before that ','
- Made suggested modifications from checkpatch in reference to WARNING:
Missing a blank line after declarations
Signed-off-by: Yi Zhuang <zhuangyi1@huawei.com>
Signed-off-by: Jia Yang <jiayang5@huawei.com>
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
With the default DPOLICY_BG discard thread is ioaware, which prevents
the discard thread from issuing the discard commands. On low RAM setups,
it is observed that these discard commands in the cache are consuming
high memory. This patch aims to relax the memory pressure on the system
due to f2fs pending discard cmds by changing the policy to DPOLICY_FORCE
based on the nm_i->ram_thresh configured.
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
butt3rflyh4ck <butterflyhuangxx@gmail.com> reported a bug found by
syzkaller fuzzer with custom modifications in 5.12.0-rc3+ [1]:
dump_stack+0xfa/0x151 lib/dump_stack.c:120
print_address_description.constprop.0.cold+0x82/0x32c mm/kasan/report.c:232
__kasan_report mm/kasan/report.c:399 [inline]
kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
f2fs_test_bit fs/f2fs/f2fs.h:2572 [inline]
current_nat_addr fs/f2fs/node.h:213 [inline]
get_next_nat_page fs/f2fs/node.c:123 [inline]
__flush_nat_entry_set fs/f2fs/node.c:2888 [inline]
f2fs_flush_nat_entries+0x258e/0x2960 fs/f2fs/node.c:2991
f2fs_write_checkpoint+0x1372/0x6a70 fs/f2fs/checkpoint.c:1640
f2fs_issue_checkpoint+0x149/0x410 fs/f2fs/checkpoint.c:1807
f2fs_sync_fs+0x20f/0x420 fs/f2fs/super.c:1454
__sync_filesystem fs/sync.c:39 [inline]
sync_filesystem fs/sync.c:67 [inline]
sync_filesystem+0x1b5/0x260 fs/sync.c:48
generic_shutdown_super+0x70/0x370 fs/super.c:448
kill_block_super+0x97/0xf0 fs/super.c:1394
The root cause is, if nat entry in checkpoint journal area is corrupted,
e.g. nid of journalled nat entry exceeds max nid value, during checkpoint,
once it tries to flush nat journal to NAT area, get_next_nat_page() may
access out-of-bounds memory on nat_bitmap due to it uses wrong nid value
as bitmap offset.
[1] https://lore.kernel.org/lkml/CAFcO6XOMWdr8pObek6eN6-fs58KG9doRFadgJj-FnF-1x43s2g@mail.gmail.com/T/#u
Reported-and-tested-by: butt3rflyh4ck <butterflyhuangxx@gmail.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
It's often inconvenient to use BIO_MAX_PAGES due to min() requiring the
sign to be the same. Introduce bio_max_segs() and change BIO_MAX_PAGES to
be unsigned to make it easier for the users.
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch deprecates f2fs_trace_io, since f2fs uses page->private more broadly,
resulting in more buggy cases.
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
During recovery, we may missed to update inline xattr count correctly,
fix it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When running fault injection test, if we don't stop checkpoint, some stale
NAT entries were flushed which breaks consistency.
Fixes: 86f33603f8 ("f2fs: handle errors of f2fs_get_meta_page_nofail")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
First problem is we hit BUG_ON() in f2fs_get_sum_page given EIO on
f2fs_get_meta_page_nofail().
Quick fix was not to give any error with infinite loop, but syzbot caught
a case where it goes to that loop from fuzzed image. In turned out we abused
f2fs_get_meta_page_nofail() like in the below call stack.
- f2fs_fill_super
- f2fs_build_segment_manager
- build_sit_entries
- get_current_sit_page
INFO: task syz-executor178:6870 can't die for more than 143 seconds.
task:syz-executor178 state:R
stack:26960 pid: 6870 ppid: 6869 flags:0x00004006
Call Trace:
Showing all locks held in the system:
1 lock held by khungtaskd/1179:
#0: ffffffff8a554da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6242
1 lock held by systemd-journal/3920:
1 lock held by in:imklog/6769:
#0: ffff88809eebc130 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930
1 lock held by syz-executor178/6870:
#0: ffff8880925120e0 (&type->s_umount_key#47/1){+.+.}-{3:3}, at: alloc_super+0x201/0xaf0 fs/super.c:229
Actually, we didn't have to use _nofail in this case, since we could return
error to mount(2) already with the error handler.
As a result, this patch tries to 1) remove _nofail callers as much as possible,
2) deal with error case in last remaining caller, f2fs_get_sum_page().
Reported-by: syzbot+ee250ac8137be41d7b13@syzkaller.appspotmail.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
A NULL will not be return by __bitmap_ptr here.
Remove the unused check.
Signed-off-by: Wang Xiaojun <wangxiaojun11@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
After commit 0b6d4ca04a ("f2fs: don't return vmalloc() memory from
f2fs_kmalloc()"), f2fs_k{m,z}alloc() will not return vmalloc()'ed
memory, so clean up to use kfree() instead of kvfree() to free
vmalloc()'ed memory.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If the sbi->ckpt->next_free_nid is not NAT block aligned and if there
are free nids in that NAT block between the start of the block and
next_free_nid, then those free nids will not be scanned in scan_nat_page().
This results into mismatch between nm_i->available_nids and the sum of
nm_i->free_nid_count of all NAT blocks scanned. And nm_i->available_nids
will always be greater than the sum of free nids in all the blocks.
Under this condition, if we use all the currently scanned free nids,
then it will loop forever in f2fs_alloc_nid() as nm_i->available_nids
is still not zero but nm_i->free_nid_count of that partially scanned
NAT block is zero.
Fix this to align the nm_i->next_scan_nid to the first nid of the
corresponding NAT block.
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Just for code style, no logic change
1. delete useless space
2. change spaces into tab
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The return value of f2fs_flush_inline_data() is not used,
so delete it.
Signed-off-by: Jia Yang <jiayang5@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
https://bugzilla.kernel.org/show_bug.cgi?id=208565
PID: 257 TASK: ecdd0000 CPU: 0 COMMAND: "init"
#0 [<c0b420ec>] (__schedule) from [<c0b423c8>]
#1 [<c0b423c8>] (schedule) from [<c0b459d4>]
#2 [<c0b459d4>] (rwsem_down_read_failed) from [<c0b44fa0>]
#3 [<c0b44fa0>] (down_read) from [<c044233c>]
#4 [<c044233c>] (f2fs_truncate_blocks) from [<c0442890>]
#5 [<c0442890>] (f2fs_truncate) from [<c044d408>]
#6 [<c044d408>] (f2fs_evict_inode) from [<c030be18>]
#7 [<c030be18>] (evict) from [<c030a558>]
#8 [<c030a558>] (iput) from [<c047c600>]
#9 [<c047c600>] (f2fs_sync_node_pages) from [<c0465414>]
#10 [<c0465414>] (f2fs_write_checkpoint) from [<c04575f4>]
#11 [<c04575f4>] (f2fs_sync_fs) from [<c0441918>]
#12 [<c0441918>] (f2fs_do_sync_file) from [<c0441098>]
#13 [<c0441098>] (f2fs_sync_file) from [<c0323fa0>]
#14 [<c0323fa0>] (vfs_fsync_range) from [<c0324294>]
#15 [<c0324294>] (do_fsync) from [<c0324014>]
#16 [<c0324014>] (sys_fsync) from [<c0108bc0>]
This can be caused by flush_dirty_inode() in f2fs_sync_node_pages() where
iput() requires f2fs_lock_op() again resulting in livelock.
Reported-by: Zhiguo Niu <Zhiguo.Niu@unisoc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Linus Torvalds
Matthew Wilcox (Oracle)
Chao Yu
Bart Van Assche
Jaegeuk Kim
Daeho Jeong
Chao Yu
Tim Murray
NeilBrown
Weichao Guo
Chao Yu
Yi Zhuang
Sahitya Tummala
Zheng Yongjun
Wang Xiaojun
Gustavo A. R. Silva
Jack Qiu
Jia Yang