Commit Graph

17 Commits

Author SHA1 Message Date
Linus Torvalds 5e714bf171 - Alistair Popple has a series which addresses a race which causes page
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
  ...
2022-10-14 12:28:43 -07:00
Matthew Wilcox (Oracle) 4fa0e3ff21 ext4,f2fs: fix readahead of verity data
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>
2022-10-12 18:51:48 -07:00
Chao Yu 95fa90c9e5 f2fs: support recording errors into superblock
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>
2022-10-04 13:31:45 -07:00
Eric Biggers b87846bd61 f2fs: use memcpy_{to,from}_page() where possible
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>
2022-08-29 21:15:51 -07:00
Linus Torvalds 1501f707d2 f2fs-for-5.19
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
  ...
2022-05-31 16:52:59 -07:00
Jaegeuk Kim 7bc155fec5 f2fs: kill volatile write support
There's no user, since all can use atomic writes simply.
Let's kill it.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2022-05-12 10:14:03 -07:00
Matthew Wilcox (Oracle) 6e0ee04465 f2fs: Call aops write_begin() and write_end() directly
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>
2022-05-08 14:45:56 -04:00
Tim Murray e4544b63a7 f2fs: move f2fs to use reader-unfair rwsems
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>
2022-01-24 17:40:04 -08:00
Chao Yu 10a2687856 f2fs: support fault injection for dquot_initialize()
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>
2021-10-29 10:38:53 -07:00
Linus Torvalds d0195c7d7a f2fs-for-5.13-rc1
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
  ...
2021-05-04 18:03:38 -07:00
Matthew Wilcox (Oracle) fcd9ae4f7f mm/filemap: Pass the file_ra_state in the ractl
For readahead_expand(), we need to modify the file ra_state, so pass it
down by adding it to the ractl.  We have to do this because it's not always
the same as f_ra in the struct file that is already being passed.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
Link: https://lore.kernel.org/r/20210407201857.3582797-2-willy@infradead.org/
Link: https://lore.kernel.org/r/161789067431.6155.8063840447229665720.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 09:25:00 +01:00
Eric Biggers 3c0315424f f2fs: fix error handling in f2fs_end_enable_verity()
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>
2021-03-12 13:16:44 -08:00
Matthew Wilcox (Oracle) 73bb49da50 mm/readahead: make page_cache_ra_unbounded take a readahead_control
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>
2020-10-16 11:11:16 -07:00
Jack Qiu 8fa41016f0 f2fs: use macro instead of f2fs verity version
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>
2020-08-03 10:32:51 -07:00
Matthew Wilcox (Oracle) 2c684234d3 mm: add page_cache_readahead_unbounded
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>
2020-06-02 10:59:06 -07:00
Eric Biggers fd39073dba fs-verity: implement readahead of Merkle tree pages
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>
2020-01-14 13:27:32 -08:00
Eric Biggers 95ae251fe8 f2fs: add fs-verity support
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>
2019-08-12 19:33:51 -07:00