In this round, we've got a huge number of patches that improve code readability
along with minor bug fixes, while we've mainly fixed some critical issues in
recently-added per-block age-based extent_cache, atomic write support, and some
folio cases.
Enhancement:
- add sysfs nodes to set last_age_weight and manage discard_io_aware_gran
- show ipu policy in debugfs
- reduce stack memory cost by using bitfield in struct f2fs_io_info
- introduce trace_f2fs_replace_atomic_write_block
- enhance iostat support and adds flush commands
Bug fix:
- revert "f2fs: truncate blocks in batch in __complete_revoke_list()"
- fix kernel crash on the atomic write abort flow
- call clear_page_private_reference in .{release,invalid}_folio
- support .migrate_folio for compressed inode
- fix cgroup writeback accounting with fs-layer encryption
- retry to update the inode page given data corruption
- fix kernel crash due to null io->bio
- fix some bugs in per-block age-based extent_cache:
a. wrong calculation of block age
b. update age extent in f2fs_do_zero_range()
c. update age extent correctly during truncation
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Merge tag 'f2fs-for-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've got a huge number of patches that improve code
readability along with minor bug fixes, while we've mainly fixed some
critical issues in recently-added per-block age-based extent_cache,
atomic write support, and some folio cases.
Enhancements:
- add sysfs nodes to set last_age_weight and manage
discard_io_aware_gran
- show ipu policy in debugfs
- reduce stack memory cost by using bitfield in struct f2fs_io_info
- introduce trace_f2fs_replace_atomic_write_block
- enhance iostat support and adds flush commands
Bug fixes:
- revert "f2fs: truncate blocks in batch in __complete_revoke_list()"
- fix kernel crash on the atomic write abort flow
- call clear_page_private_reference in .{release,invalid}_folio
- support .migrate_folio for compressed inode
- fix cgroup writeback accounting with fs-layer encryption
- retry to update the inode page given data corruption
- fix kernel crash due to NULL io->bio
- fix some bugs in per-block age-based extent_cache:
- wrong calculation of block age
- update age extent in f2fs_do_zero_range()
- update age extent correctly during truncation"
* tag 'f2fs-for-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (81 commits)
f2fs: drop unnecessary arg for f2fs_ioc_*()
f2fs: Revert "f2fs: truncate blocks in batch in __complete_revoke_list()"
f2fs: synchronize atomic write aborts
f2fs: fix wrong segment count
f2fs: replace si->sbi w/ sbi in stat_show()
f2fs: export ipu policy in debugfs
f2fs: make kobj_type structures constant
f2fs: fix to do sanity check on extent cache correctly
f2fs: add missing description for ipu_policy node
f2fs: fix to set ipu policy
f2fs: fix typos in comments
f2fs: fix kernel crash due to null io->bio
f2fs: use iostat_lat_type directly as a parameter in the iostat_update_and_unbind_ctx()
f2fs: add sysfs nodes to set last_age_weight
f2fs: fix f2fs_show_options to show nogc_merge mount option
f2fs: fix cgroup writeback accounting with fs-layer encryption
f2fs: fix wrong calculation of block age
f2fs: fix to update age extent in f2fs_do_zero_range()
f2fs: fix to update age extent correctly during truncation
f2fs: fix to avoid potential memory corruption in __update_iostat_latency()
...
When aops->write_begin() does not initialize fsdata, KMSAN may report
an error passing the latter to aops->write_end().
Fix this by unconditionally initializing fsdata.
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Fixes: 95ae251fe8 ("f2fs: add fs-verity support")
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
fsverity_operations::write_merkle_tree_block is passed the index of the
block to write and the log base 2 of the block size. However, all
implementations of it use these parameters only to calculate the
position and the size of the block, in bytes.
Therefore, make ->write_merkle_tree_block take 'pos' and 'size'
parameters instead of 'index' and 'log_blocksize'.
Suggested-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20221214224304.145712-5-ebiggers@kernel.org
refcounting errors in ZONE_DEVICE pages.
- Peter Xu fixes some userfaultfd test harness instability.
- Various other patches in MM, mainly fixes.
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Merge tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton:
- fix a race which causes page refcounting errors in ZONE_DEVICE pages
(Alistair Popple)
- fix userfaultfd test harness instability (Peter Xu)
- various other patches in MM, mainly fixes
* tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (29 commits)
highmem: fix kmap_to_page() for kmap_local_page() addresses
mm/page_alloc: fix incorrect PGFREE and PGALLOC for high-order page
mm/selftest: uffd: explain the write missing fault check
mm/hugetlb: use hugetlb_pte_stable in migration race check
mm/hugetlb: fix race condition of uffd missing/minor handling
zram: always expose rw_page
LoongArch: update local TLB if PTE entry exists
mm: use update_mmu_tlb() on the second thread
kasan: fix array-bounds warnings in tests
hmm-tests: add test for migrate_device_range()
nouveau/dmem: evict device private memory during release
nouveau/dmem: refactor nouveau_dmem_fault_copy_one()
mm/migrate_device.c: add migrate_device_range()
mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page()
mm/memremap.c: take a pgmap reference on page allocation
mm: free device private pages have zero refcount
mm/memory.c: fix race when faulting a device private page
mm/damon: use damon_sz_region() in appropriate place
mm/damon: move sz_damon_region to damon_sz_region
lib/test_meminit: add checks for the allocation functions
...
The recent change of page_cache_ra_unbounded() arguments was buggy in the
two callers, causing us to readahead the wrong pages. Move the definition
of ractl down to after the index is set correctly. This affected
performance on configurations that use fs-verity.
Link: https://lkml.kernel.org/r/20221012193419.1453558-1-willy@infradead.org
Fixes: 73bb49da50 ("mm/readahead: make page_cache_ra_unbounded take a readahead_control")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reported-by: Jintao Yin <nicememory@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This patch supports to record detail reason of FSCORRUPTED error into
f2fs_super_block.s_errors[].
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This is simpler, and as a side effect it replaces several uses of
kmap_atomic() with its recommended replacement kmap_local_page().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
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
...
pagecache_write_begin() and pagecache_write_end() are now trivial
wrappers, so call the aops directly.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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>
This patch adds a new function f2fs_dquot_initialize() to wrap
dquot_initialize(), and it supports to inject fault into
f2fs_dquot_initialize() to simulate inner failure occurs in
dquot_initialize().
Usage:
a) echo 65536 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=65536 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this round, we added a new mount option, "checkpoint_merge", which introduces
a kernel thread dealing with the f2fs checkpoints. Once we start to manage the
IO priority along with blk-cgroup, the checkpoint operation can be processed in
a lower priority under the process context. Since the checkpoint holds all the
filesystem operations, we give a higher priority to the checkpoint thread all
the time.
Enhancement:
- introduce gc_merge mount option to introduce a checkpoint thread
- improve to run discard thread efficiently
- allow modular compression algorithms
- expose # of overprivision segments to sysfs
- expose runtime compression stat to sysfs
Bug fix:
- fix OOB memory access by the node id lookup
- avoid touching checkpointed data in the checkpoint-disabled mode
- fix the resizing flow to avoid kernel panic and race conditions
- fix block allocation issues on pinned files
- address some swapfile issues
- fix hugtask problem and kernel panic during atomic write operations
- don't start checkpoint thread in RO
And, we've cleaned up some kernel coding style and build warnings. In addition,
we fixed some minor race conditions and error handling routines.
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Merge tag 'f2fs-for-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we added a new mount option, "checkpoint_merge", which
introduces a kernel thread dealing with the f2fs checkpoints. Once we
start to manage the IO priority along with blk-cgroup, the checkpoint
operation can be processed in a lower priority under the process
context. Since the checkpoint holds all the filesystem operations, we
give a higher priority to the checkpoint thread all the time.
Enhancements:
- introduce gc_merge mount option to introduce a checkpoint thread
- improve to run discard thread efficiently
- allow modular compression algorithms
- expose # of overprivision segments to sysfs
- expose runtime compression stat to sysfs
Bug fixes:
- fix OOB memory access by the node id lookup
- avoid touching checkpointed data in the checkpoint-disabled mode
- fix the resizing flow to avoid kernel panic and race conditions
- fix block allocation issues on pinned files
- address some swapfile issues
- fix hugtask problem and kernel panic during atomic write operations
- don't start checkpoint thread in RO
And, we've cleaned up some kernel coding style and build warnings. In
addition, we fixed some minor race conditions and error handling
routines"
* tag 'f2fs-for-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (48 commits)
f2fs: drop inplace IO if fs status is abnormal
f2fs: compress: remove unneed check condition
f2fs: clean up left deprecated IO trace codes
f2fs: avoid using native allocate_segment_by_default()
f2fs: remove unnecessary struct declaration
f2fs: fix to avoid NULL pointer dereference
f2fs: avoid duplicated codes for cleanup
f2fs: document: add description about compressed space handling
f2fs: clean up build warnings
f2fs: fix the periodic wakeups of discard thread
f2fs: fix to avoid accessing invalid fio in f2fs_allocate_data_block()
f2fs: fix to avoid GC/mmap race with f2fs_truncate()
f2fs: set checkpoint_merge by default
f2fs: Fix a hungtask problem in atomic write
f2fs: fix to restrict mount condition on readonly block device
f2fs: introduce gc_merge mount option
f2fs: fix to cover __allocate_new_section() with curseg_lock
f2fs: fix wrong alloc_type in f2fs_do_replace_block
f2fs: delete empty compress.h
f2fs: fix a typo in inode.c
...
f2fs didn't properly clean up if verity failed to be enabled on a file:
- It left verity metadata (pages past EOF) in the page cache, which
would be exposed to userspace if the file was later extended.
- It didn't truncate the verity metadata at all (either from cache or
from disk) if an error occurred while setting the verity bit.
Fix these bugs by adding a call to truncate_inode_pages() and ensuring
that we truncate the verity metadata (both from cache and from disk) in
all error paths. Also rework the code to cleanly separate the success
path from the error paths, which makes it much easier to understand.
Finally, log a message if f2fs_truncate() fails, since it might
otherwise fail silently.
Reported-by: Yunlei He <heyunlei@hihonor.com>
Fixes: 95ae251fe8 ("f2fs: add fs-verity support")
Cc: <stable@vger.kernel.org> # v5.4+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Define it in the callers instead of in page_cache_ra_unbounded().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Eric Biggers <ebiggers@google.com>
Link: https://lkml.kernel.org/r/20200903140844.14194-4-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Because fsverity_descriptor_location.version is constant,
so use macro for better reading.
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
ext4 and f2fs have duplicated the guts of the readahead code so they can
read past i_size. Instead, separate out the guts of the readahead code
so they can call it directly.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Link: http://lkml.kernel.org/r/20200414150233.24495-14-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When fs-verity verifies data pages, currently it reads each Merkle tree
page synchronously using read_mapping_page().
Therefore, when the Merkle tree pages aren't already cached, fs-verity
causes an extra 4 KiB I/O request for every 512 KiB of data (assuming
that the Merkle tree uses SHA-256 and 4 KiB blocks). This results in
more I/O requests and performance loss than is strictly necessary.
Therefore, implement readahead of the Merkle tree pages.
For simplicity, we take advantage of the fact that the kernel already
does readahead of the file's *data*, just like it does for any other
file. Due to this, we don't really need a separate readahead state
(struct file_ra_state) just for the Merkle tree, but rather we just need
to piggy-back on the existing data readahead requests.
We also only really need to bother with the first level of the Merkle
tree, since the usual fan-out factor is 128, so normally over 99% of
Merkle tree I/O requests are for the first level.
Therefore, make fsverity_verify_bio() enable readahead of the first
Merkle tree level, for up to 1/4 the number of pages in the bio, when it
sees that the REQ_RAHEAD flag is set on the bio. The readahead size is
then passed down to ->read_merkle_tree_page() for the filesystem to
(optionally) implement if it sees that the requested page is uncached.
While we're at it, also make build_merkle_tree_level() set the Merkle
tree readahead size, since it's easy to do there.
However, for now don't set the readahead size in fsverity_verify_page(),
since currently it's only used to verify holes on ext4 and f2fs, and it
would need parameters added to know how much to read ahead.
This patch significantly improves fs-verity sequential read performance.
Some quick benchmarks with 'cat'-ing a 250MB file after dropping caches:
On an ARM64 phone (using sha256-ce):
Before: 217 MB/s
After: 263 MB/s
(compare to sha256sum of non-verity file: 357 MB/s)
In an x86_64 VM (using sha256-avx2):
Before: 173 MB/s
After: 215 MB/s
(compare to sha256sum of non-verity file: 223 MB/s)
Link: https://lore.kernel.org/r/20200106205533.137005-1-ebiggers@kernel.org
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Add fs-verity support to f2fs. fs-verity is a filesystem feature that
enables transparent integrity protection and authentication of read-only
files. It uses a dm-verity like mechanism at the file level: a Merkle
tree is used to verify any block in the file in log(filesize) time. It
is implemented mainly by helper functions in fs/verity/. See
Documentation/filesystems/fsverity.rst for the full documentation.
The f2fs support for fs-verity consists of:
- Adding a filesystem feature flag and an inode flag for fs-verity.
- Implementing the fsverity_operations to support enabling verity on an
inode and reading/writing the verity metadata.
- Updating ->readpages() to verify data as it's read from verity files
and to support reading verity metadata pages.
- Updating ->write_begin(), ->write_end(), and ->writepages() to support
writing verity metadata pages.
- Calling the fs-verity hooks for ->open(), ->setattr(), and ->ioctl().
Like ext4, f2fs stores the verity metadata (Merkle tree and
fsverity_descriptor) past the end of the file, starting at the first 64K
boundary beyond i_size. This approach works because (a) verity files
are readonly, and (b) pages fully beyond i_size aren't visible to
userspace but can be read/written internally by f2fs with only some
relatively small changes to f2fs. Extended attributes cannot be used
because (a) f2fs limits the total size of an inode's xattr entries to
4096 bytes, which wouldn't be enough for even a single Merkle tree
block, and (b) f2fs encryption doesn't encrypt xattrs, yet the verity
metadata *must* be encrypted when the file is because it contains hashes
of the plaintext data.
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Linus Torvalds