- The 4 patch series "mm: ksm: prevent KSM from breaking merging of new
VMAs" from Lorenzo Stoakes addresses an issue with KSM's
PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for
merging with existing adjacent VMAs.
- The 4 patch series "mm/damon: introduce DAMON_STAT for simple and
practical access monitoring" from SeongJae Park adds a new kernel module
which simplifies the setup and usage of DAMON in production
environments.
- The 6 patch series "stop passing a writeback_control to swap/shmem
writeout" from Christoph Hellwig is a cleanup to the writeback code
which removes a couple of pointers from struct writeback_control.
- The 7 patch series "drivers/base/node.c: optimization and cleanups"
from Donet Tom contains largely uncorrelated cleanups to the NUMA node
setup and management code.
- The 4 patch series "mm: userfaultfd: assorted fixes and cleanups" from
Tal Zussman does some maintenance work on the userfaultfd code.
- The 5 patch series "Readahead tweaks for larger folios" from Ryan
Roberts implements some tuneups for pagecache readahead when it is
reading into order>0 folios.
- The 4 patch series "selftests/mm: Tweaks to the cow test" from Mark
Brown provides some cleanups and consistency improvements to the
selftests code.
- The 4 patch series "Optimize mremap() for large folios" from Dev Jain
does that. A 37% reduction in execution time was measured in a
memset+mremap+munmap microbenchmark.
- The 5 patch series "Remove zero_user()" from Matthew Wilcox expunges
zero_user() in favor of the more modern memzero_page().
- The 3 patch series "mm/huge_memory: vmf_insert_folio_*() and
vmf_insert_pfn_pud() fixes" from David Hildenbrand addresses some warts
which David noticed in the huge page code. These were not known to be
causing any issues at this time.
- The 3 patch series "mm/damon: use alloc_migrate_target() for
DAMOS_MIGRATE_{HOT,COLD" from SeongJae Park provides some cleanup and
consolidation work in DAMON.
- The 3 patch series "use vm_flags_t consistently" from Lorenzo Stoakes
uses vm_flags_t in places where we were inappropriately using other
types.
- The 3 patch series "mm/memfd: Reserve hugetlb folios before
allocation" from Vivek Kasireddy increases the reliability of large page
allocation in the memfd code.
- The 14 patch series "mm: Remove pXX_devmap page table bit and pfn_t
type" from Alistair Popple removes several now-unneeded PFN_* flags.
- The 5 patch series "mm/damon: decouple sysfs from core" from SeongJae
Park implememnts some cleanup and maintainability work in the DAMON
sysfs layer.
- The 5 patch series "madvise cleanup" from Lorenzo Stoakes does quite a
lot of cleanup/maintenance work in the madvise() code.
- The 4 patch series "madvise anon_name cleanups" from Vlastimil Babka
provides additional cleanups on top or Lorenzo's effort.
- The 11 patch series "Implement numa node notifier" from Oscar Salvador
creates a standalone notifier for NUMA node memory state changes.
Previously these were lumped under the more general memory on/offline
notifier.
- The 6 patch series "Make MIGRATE_ISOLATE a standalone bit" from Zi Yan
cleans up the pageblock isolation code and fixes a potential issue which
doesn't seem to cause any problems in practice.
- The 5 patch series "selftests/damon: add python and drgn based DAMON
sysfs functionality tests" from SeongJae Park adds additional drgn- and
python-based DAMON selftests which are more comprehensive than the
existing selftest suite.
- The 5 patch series "Misc rework on hugetlb faulting path" from Oscar
Salvador fixes a rather obscure deadlock in the hugetlb fault code and
follows that fix with a series of cleanups.
- The 3 patch series "cma: factor out allocation logic from
__cma_declare_contiguous_nid" from Mike Rapoport rationalizes and cleans
up the highmem-specific code in the CMA allocator.
- The 28 patch series "mm/migration: rework movable_ops page migration
(part 1)" from David Hildenbrand provides cleanups and
future-preparedness to the migration code.
- The 2 patch series "mm/damon: add trace events for auto-tuned
monitoring intervals and DAMOS quota" from SeongJae Park adds some
tracepoints to some DAMON auto-tuning code.
- The 6 patch series "mm/damon: fix misc bugs in DAMON modules" from
SeongJae Park does that.
- The 6 patch series "mm/damon: misc cleanups" from SeongJae Park also
does what it claims.
- The 4 patch series "mm: folio_pte_batch() improvements" from David
Hildenbrand cleans up the large folio PTE batching code.
- The 13 patch series "mm/damon/vaddr: Allow interleaving in
migrate_{hot,cold} actions" from SeongJae Park facilitates dynamic
alteration of DAMON's inter-node allocation policy.
- The 3 patch series "Remove unmap_and_put_page()" from Vishal Moola
provides a couple of page->folio conversions.
- The 4 patch series "mm: per-node proactive reclaim" from Davidlohr
Bueso implements a per-node control of proactive reclaim - beyond the
current memcg-based implementation.
- The 14 patch series "mm/damon: remove damon_callback" from SeongJae
Park replaces the damon_callback interface with a more general and
powerful damon_call()+damos_walk() interface.
- The 10 patch series "mm/mremap: permit mremap() move of multiple VMAs"
from Lorenzo Stoakes implements a number of mremap cleanups (of course)
in preparation for adding new mremap() functionality: newly permit the
remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It
still excludes some specialized situations where this cannot be
performed reliably.
- The 3 patch series "drop hugetlb_free_pgd_range()" from Anthony Yznaga
switches some sparc hugetlb code over to the generic version and removes
the thus-unneeded hugetlb_free_pgd_range().
- The 4 patch series "mm/damon/sysfs: support periodic and automated
stats update" from SeongJae Park augments the present
userspace-requested update of DAMON sysfs monitoring files. Automatic
update is now provided, along with a tunable to control the update
interval.
- The 4 patch series "Some randome fixes and cleanups to swapfile" from
Kemeng Shi does what is claims.
- The 4 patch series "mm: introduce snapshot_page" from Luiz Capitulino
and David Hildenbrand provides (and uses) a means by which debug-style
functions can grab a copy of a pageframe and inspect it locklessly
without tripping over the races inherent in operating on the live
pageframe directly.
- The 6 patch series "use per-vma locks for /proc/pid/maps reads" from
Suren Baghdasaryan addresses the large contention issues which can be
triggered by reads from that procfs file. Latencies are reduced by more
than half in some situations. The series also introduces several new
selftests for the /proc/pid/maps interface.
- The 6 patch series "__folio_split() clean up" from Zi Yan cleans up
__folio_split()!
- The 7 patch series "Optimize mprotect() for large folios" from Dev
Jain provides some quite large (>3x) speedups to mprotect() when dealing
with large folios.
- The 2 patch series "selftests/mm: reuse FORCE_READ to replace "asm
volatile("" : "+r" (XXX));" and some cleanup" from wang lian does some
cleanup work in the selftests code.
- The 3 patch series "tools/testing: expand mremap testing" from Lorenzo
Stoakes extends the mremap() selftest in several ways, including adding
more checking of Lorenzo's recently added "permit mremap() move of
multiple VMAs" feature.
- The 22 patch series "selftests/damon/sysfs.py: test all parameters"
from SeongJae Park extends the DAMON sysfs interface selftest so that it
tests all possible user-requested parameters. Rather than the present
minimal subset.
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Merge tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"As usual, many cleanups. The below blurbiage describes 42 patchsets.
21 of those are partially or fully cleanup work. "cleans up",
"cleanup", "maintainability", "rationalizes", etc.
I never knew the MM code was so dirty.
"mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes)
addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly
mapped VMAs were not eligible for merging with existing adjacent
VMAs.
"mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park)
adds a new kernel module which simplifies the setup and usage of
DAMON in production environments.
"stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig)
is a cleanup to the writeback code which removes a couple of
pointers from struct writeback_control.
"drivers/base/node.c: optimization and cleanups" (Donet Tom)
contains largely uncorrelated cleanups to the NUMA node setup and
management code.
"mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman)
does some maintenance work on the userfaultfd code.
"Readahead tweaks for larger folios" (Ryan Roberts)
implements some tuneups for pagecache readahead when it is reading
into order>0 folios.
"selftests/mm: Tweaks to the cow test" (Mark Brown)
provides some cleanups and consistency improvements to the
selftests code.
"Optimize mremap() for large folios" (Dev Jain)
does that. A 37% reduction in execution time was measured in a
memset+mremap+munmap microbenchmark.
"Remove zero_user()" (Matthew Wilcox)
expunges zero_user() in favor of the more modern memzero_page().
"mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand)
addresses some warts which David noticed in the huge page code.
These were not known to be causing any issues at this time.
"mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park)
provides some cleanup and consolidation work in DAMON.
"use vm_flags_t consistently" (Lorenzo Stoakes)
uses vm_flags_t in places where we were inappropriately using other
types.
"mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy)
increases the reliability of large page allocation in the memfd
code.
"mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple)
removes several now-unneeded PFN_* flags.
"mm/damon: decouple sysfs from core" (SeongJae Park)
implememnts some cleanup and maintainability work in the DAMON
sysfs layer.
"madvise cleanup" (Lorenzo Stoakes)
does quite a lot of cleanup/maintenance work in the madvise() code.
"madvise anon_name cleanups" (Vlastimil Babka)
provides additional cleanups on top or Lorenzo's effort.
"Implement numa node notifier" (Oscar Salvador)
creates a standalone notifier for NUMA node memory state changes.
Previously these were lumped under the more general memory
on/offline notifier.
"Make MIGRATE_ISOLATE a standalone bit" (Zi Yan)
cleans up the pageblock isolation code and fixes a potential issue
which doesn't seem to cause any problems in practice.
"selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park)
adds additional drgn- and python-based DAMON selftests which are
more comprehensive than the existing selftest suite.
"Misc rework on hugetlb faulting path" (Oscar Salvador)
fixes a rather obscure deadlock in the hugetlb fault code and
follows that fix with a series of cleanups.
"cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport)
rationalizes and cleans up the highmem-specific code in the CMA
allocator.
"mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand)
provides cleanups and future-preparedness to the migration code.
"mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park)
adds some tracepoints to some DAMON auto-tuning code.
"mm/damon: fix misc bugs in DAMON modules" (SeongJae Park)
does that.
"mm/damon: misc cleanups" (SeongJae Park)
also does what it claims.
"mm: folio_pte_batch() improvements" (David Hildenbrand)
cleans up the large folio PTE batching code.
"mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park)
facilitates dynamic alteration of DAMON's inter-node allocation
policy.
"Remove unmap_and_put_page()" (Vishal Moola)
provides a couple of page->folio conversions.
"mm: per-node proactive reclaim" (Davidlohr Bueso)
implements a per-node control of proactive reclaim - beyond the
current memcg-based implementation.
"mm/damon: remove damon_callback" (SeongJae Park)
replaces the damon_callback interface with a more general and
powerful damon_call()+damos_walk() interface.
"mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes)
implements a number of mremap cleanups (of course) in preparation
for adding new mremap() functionality: newly permit the remapping
of multiple VMAs when the user is specifying MREMAP_FIXED. It still
excludes some specialized situations where this cannot be performed
reliably.
"drop hugetlb_free_pgd_range()" (Anthony Yznaga)
switches some sparc hugetlb code over to the generic version and
removes the thus-unneeded hugetlb_free_pgd_range().
"mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park)
augments the present userspace-requested update of DAMON sysfs
monitoring files. Automatic update is now provided, along with a
tunable to control the update interval.
"Some randome fixes and cleanups to swapfile" (Kemeng Shi)
does what is claims.
"mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand)
provides (and uses) a means by which debug-style functions can grab
a copy of a pageframe and inspect it locklessly without tripping
over the races inherent in operating on the live pageframe
directly.
"use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan)
addresses the large contention issues which can be triggered by
reads from that procfs file. Latencies are reduced by more than
half in some situations. The series also introduces several new
selftests for the /proc/pid/maps interface.
"__folio_split() clean up" (Zi Yan)
cleans up __folio_split()!
"Optimize mprotect() for large folios" (Dev Jain)
provides some quite large (>3x) speedups to mprotect() when dealing
with large folios.
"selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian)
does some cleanup work in the selftests code.
"tools/testing: expand mremap testing" (Lorenzo Stoakes)
extends the mremap() selftest in several ways, including adding
more checking of Lorenzo's recently added "permit mremap() move of
multiple VMAs" feature.
"selftests/damon/sysfs.py: test all parameters" (SeongJae Park)
extends the DAMON sysfs interface selftest so that it tests all
possible user-requested parameters. Rather than the present minimal
subset"
* tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits)
MAINTAINERS: add missing headers to mempory policy & migration section
MAINTAINERS: add missing file to cgroup section
MAINTAINERS: add MM MISC section, add missing files to MISC and CORE
MAINTAINERS: add missing zsmalloc file
MAINTAINERS: add missing files to page alloc section
MAINTAINERS: add missing shrinker files
MAINTAINERS: move memremap.[ch] to hotplug section
MAINTAINERS: add missing mm_slot.h file THP section
MAINTAINERS: add missing interval_tree.c to memory mapping section
MAINTAINERS: add missing percpu-internal.h file to per-cpu section
mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info()
selftests/damon: introduce _common.sh to host shared function
selftests/damon/sysfs.py: test runtime reduction of DAMON parameters
selftests/damon/sysfs.py: test non-default parameters runtime commit
selftests/damon/sysfs.py: generalize DAMON context commit assertion
selftests/damon/sysfs.py: generalize monitoring attributes commit assertion
selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion
selftests/damon/sysfs.py: test DAMOS filters commitment
selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion
selftests/damon/sysfs.py: test DAMOS destinations commitment
...
Simplify how fscrypt uses the crypto API, resulting in some
significant performance improvements:
- Drop the incomplete and problematic support for asynchronous
algorithms. These drivers are bug-prone, and it turns out they are
actually much slower than the CPU-based code as well.
- Allocate crypto requests on the stack instead of the heap. This
improves encryption and decryption performance, especially for
filenames. It also eliminates a point of failure during I/O.
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Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux
Pull fscrypt updates from Eric Biggers:
"Simplify how fscrypt uses the crypto API, resulting in some
significant performance improvements:
- Drop the incomplete and problematic support for asynchronous
algorithms. These drivers are bug-prone, and it turns out they are
actually much slower than the CPU-based code as well.
- Allocate crypto requests on the stack instead of the heap. This
improves encryption and decryption performance, especially for
filenames. This also eliminates a point of failure during I/O"
* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux:
ceph: Remove gfp_t argument from ceph_fscrypt_encrypt_*()
fscrypt: Remove gfp_t argument from fscrypt_encrypt_block_inplace()
fscrypt: Remove gfp_t argument from fscrypt_crypt_data_unit()
fscrypt: Switch to sync_skcipher and on-stack requests
fscrypt: Drop FORBID_WEAK_KEYS flag for AES-ECB
fscrypt: Don't use asynchronous CryptoAPI algorithms
fscrypt: Don't use problematic non-inline crypto engines
fscrypt: Drop obsolete recommendation to enable optimized SHA-512
fscrypt: Explicitly include <linux/export.h>
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Merge tag 'vfs-6.17-rc1.mmap_prepare' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull mmap_prepare updates from Christian Brauner:
"Last cycle we introduce f_op->mmap_prepare() in c84bf6dd2b ("mm:
introduce new .mmap_prepare() file callback").
This is preferred to the existing f_op->mmap() hook as it does require
a VMA to be established yet, thus allowing the mmap logic to invoke
this hook far, far earlier, prior to inserting a VMA into the virtual
address space, or performing any other heavy handed operations.
This allows for much simpler unwinding on error, and for there to be a
single attempt at merging a VMA rather than having to possibly
reattempt a merge based on potentially altered VMA state.
Far more importantly, it prevents inappropriate manipulation of
incompletely initialised VMA state, which is something that has been
the cause of bugs and complexity in the past.
The intent is to gradually deprecate f_op->mmap, and in that vein this
series coverts the majority of file systems to using f_op->mmap_prepare.
Prerequisite steps are taken - firstly ensuring all checks for mmap
capabilities use the file_has_valid_mmap_hooks() helper rather than
directly checking for f_op->mmap (which is now not a valid check) and
secondly updating daxdev_mapping_supported() to not require a VMA
parameter to allow ext4 and xfs to be converted.
Commit bb666b7c27 ("mm: add mmap_prepare() compatibility layer for
nested file systems") handles the nasty edge-case of nested file
systems like overlayfs, which introduces a compatibility shim to allow
f_op->mmap_prepare() to be invoked from an f_op->mmap() callback.
This allows for nested filesystems to continue to function correctly
with all file systems regardless of which callback is used. Once we
finally convert all file systems, this shim can be removed.
As a result, ecryptfs, fuse, and overlayfs remain unaltered so they
can nest all other file systems.
We additionally do not update resctl - as this requires an update to
remap_pfn_range() (or an alternative to it) which we defer to a later
series, equally we do not update cramfs which needs a mixed mapping
insertion with the same issue, nor do we update procfs, hugetlbfs,
syfs or kernfs all of which require VMAs for internal state and hooks.
We shall return to all of these later"
* tag 'vfs-6.17-rc1.mmap_prepare' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
doc: update porting, vfs documentation to describe mmap_prepare()
fs: replace mmap hook with .mmap_prepare for simple mappings
fs: convert most other generic_file_*mmap() users to .mmap_prepare()
fs: convert simple use of generic_file_*_mmap() to .mmap_prepare()
mm/filemap: introduce generic_file_*_mmap_prepare() helpers
fs/xfs: transition from deprecated .mmap hook to .mmap_prepare
fs/ext4: transition from deprecated .mmap hook to .mmap_prepare
fs/dax: make it possible to check dev dax support without a VMA
fs: consistently use can_mmap_file() helper
mm/nommu: use file_has_valid_mmap_hooks() helper
mm: rename call_mmap/mmap_prepare to vfs_mmap/mmap_prepare
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Merge tag 'vfs-6.17-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc VFS updates from Christian Brauner:
"This contains the usual selections of misc updates for this cycle.
Features:
- Add ext4 IOCB_DONTCACHE support
This refactors the address_space_operations write_begin() and
write_end() callbacks to take const struct kiocb * as their first
argument, allowing IOCB flags such as IOCB_DONTCACHE to propagate
to the filesystem's buffered I/O path.
Ext4 is updated to implement handling of the IOCB_DONTCACHE flag
and advertises support via the FOP_DONTCACHE file operation flag.
Additionally, the i915 driver's shmem write paths are updated to
bypass the legacy write_begin/write_end interface in favor of
directly calling write_iter() with a constructed synchronous kiocb.
Another i915 change replaces a manual write loop with
kernel_write() during GEM shmem object creation.
Cleanups:
- don't duplicate vfs_open() in kernel_file_open()
- proc_fd_getattr(): don't bother with S_ISDIR() check
- fs/ecryptfs: replace snprintf with sysfs_emit in show function
- vfs: Remove unnecessary list_for_each_entry_safe() from
evict_inodes()
- filelock: add new locks_wake_up_waiter() helper
- fs: Remove three arguments from block_write_end()
- VFS: change old_dir and new_dir in struct renamedata to dentrys
- netfs: Remove unused declaration netfs_queue_write_request()
Fixes:
- eventpoll: Fix semi-unbounded recursion
- eventpoll: fix sphinx documentation build warning
- fs/read_write: Fix spelling typo
- fs: annotate data race between poll_schedule_timeout() and
pollwake()
- fs/pipe: set FMODE_NOWAIT in create_pipe_files()
- docs/vfs: update references to i_mutex to i_rwsem
- fs/buffer: remove comment about hard sectorsize
- fs/buffer: remove the min and max limit checks in __getblk_slow()
- fs/libfs: don't assume blocksize <= PAGE_SIZE in
generic_check_addressable
- fs_context: fix parameter name in infofc() macro
- fs: Prevent file descriptor table allocations exceeding INT_MAX"
* tag 'vfs-6.17-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits)
netfs: Remove unused declaration netfs_queue_write_request()
eventpoll: fix sphinx documentation build warning
ext4: support uncached buffered I/O
mm/pagemap: add write_begin_get_folio() helper function
fs: change write_begin/write_end interface to take struct kiocb *
drm/i915: Refactor shmem_pwrite() to use kiocb and write_iter
drm/i915: Use kernel_write() in shmem object create
eventpoll: Fix semi-unbounded recursion
vfs: Remove unnecessary list_for_each_entry_safe() from evict_inodes()
fs/libfs: don't assume blocksize <= PAGE_SIZE in generic_check_addressable
fs/buffer: remove the min and max limit checks in __getblk_slow()
fs: Prevent file descriptor table allocations exceeding INT_MAX
fs: Remove three arguments from block_write_end()
fs/ecryptfs: replace snprintf with sysfs_emit in show function
fs: annotate suspected data race between poll_schedule_timeout() and pollwake()
docs/vfs: update references to i_mutex to i_rwsem
fs/buffer: remove comment about hard sectorsize
fs_context: fix parameter name in infofc() macro
VFS: change old_dir and new_dir in struct renamedata to dentrys
proc_fd_getattr(): don't bother with S_ISDIR() check
...
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Merge tag 'pull-ceph-d_name-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull ceph dentry->d_name fixes from Al Viro:
"Stuff that had fallen through the cracks back in February; ceph folks
tested that pile and said they prefer to have it go through my tree..."
* tag 'pull-ceph-d_name-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ceph: fix a race with rename() in ceph_mdsc_build_path()
prep for ceph_encode_encrypted_fname() fixes
[ceph] parse_longname(): strrchr() expects NUL-terminated string
Change the address_space_operations callbacks write_begin() and
write_end() to take struct kiocb * as the first argument instead of
struct file *.
Update all affected function prototypes, implementations, call sites,
and related documentation across VFS, filesystems, and block layer.
Part of a series refactoring address_space_operations write_begin and
write_end callbacks to use struct kiocb for passing write context and
flags.
Signed-off-by: Taotao Chen <chentaotao@didiglobal.com>
Link: https://lore.kernel.org/20250716093559.217344-4-chentaotao@didiglobal.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Retrieve a folio from the pagecache instead of a page and operate on it.
Removes several hidden calls to compound_head() along with calls to
deprecated functions like wait_on_page_writeback() and find_lock_page().
[dan.carpenter@linaro.org: fix NULL vs IS_ERR() bug in ceph_zero_partial_page()]
Link: https://lkml.kernel.org/r/685c1424.050a0220.baa8.d6a1@mx.google.com
Link: https://lkml.kernel.org/r/20250612143443.2848197-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Xiubo Li <xiubli@redhat.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Alex Markuze <amarkuze@redhat.com>
Cc: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit c84bf6dd2b ("mm: introduce new .mmap_prepare() file
callback"), the f_op->mmap() hook has been deprecated in favour of
f_op->mmap_prepare().
This callback is invoked in the mmap() logic far earlier, so error handling
can be performed more safely without complicated and bug-prone state
unwinding required should an error arise.
This hook also avoids passing a pointer to a not-yet-correctly-established
VMA avoiding any issues with referencing this data structure.
It rather provides a pointer to the new struct vm_area_desc descriptor type
which contains all required state and allows easy setting of required
parameters without any consideration needing to be paid to locking or
reference counts.
Note that nested filesystems like overlayfs are compatible with an
.mmap_prepare() callback since commit bb666b7c27 ("mm: add mmap_prepare()
compatibility layer for nested file systems").
In this patch we apply this change to file systems with relatively simple
mmap() hook logic - exfat, ceph, f2fs, bcachefs, zonefs, btrfs, ocfs2,
orangefs, nilfs2, romfs, ramfs and aio.
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Link: https://lore.kernel.org/f528ac4f35b9378931bd800920fee53fc0c5c74d.1750099179.git.lorenzo.stoakes@oracle.com
Acked-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Lift copying the name into callers of ceph_encode_encrypted_dname()
that do not have it already copied; ceph_encode_encrypted_fname()
disappears.
That fixes a UAF in ceph_mdsc_build_path() - while the initial copy
of plaintext into buf is done under ->d_lock, we access the
original name again in ceph_encode_encrypted_fname() and that is
done without any locking. With ceph_encode_encrypted_dname() using
the stable copy the problem goes away.
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
ceph_encode_encrypted_dname() would be better off with plaintext name
already copied into buffer; we'll lift that into the callers on the
next step, which will allow to fix UAF on races with rename; for now
copy it in the very beginning of ceph_encode_encrypted_dname().
That has a pleasant side benefit - we don't need to mess with tmp_buf
anymore (i.e. that's 256 bytes off the stack footprint).
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... and parse_longname() is not guaranteed that. That's the reason
why it uses kmemdup_nul() to build the argument for kstrtou64();
the problem is, kstrtou64() is not the only thing that need it.
Just get a NUL-terminated copy of the entire thing and be done
with that...
Fixes: dd66df0053 "ceph: add support for encrypted snapshot names"
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... to be used instead of manually assigning to ->s_d_op.
All in-tree filesystem converted (and field itself is renamed,
so any out-of-tree ones in need of conversion will be caught
by compiler).
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
performance improvement in cases where an IMA policy with rules that
are based on fsmagic matching is enforced, an encryption-related fixup
that addresses generic/397 and other fstest failures and a couple of
cleanups in CephFS.
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Merge tag 'ceph-for-6.16-rc1' of https://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
- a one-liner that leads to a startling (but also very much rational)
performance improvement in cases where an IMA policy with rules that
are based on fsmagic matching is enforced
- an encryption-related fixup that addresses generic/397 and other
fstest failures
- a couple of cleanups in CephFS
* tag 'ceph-for-6.16-rc1' of https://github.com/ceph/ceph-client:
ceph: fix variable dereferenced before check in ceph_umount_begin()
ceph: set superblock s_magic for IMA fsmagic matching
ceph: cleanup hardcoded constants of file handle size
ceph: fix possible integer overflow in ceph_zero_objects()
ceph: avoid kernel BUG for encrypted inode with unaligned file size
smatch warnings:
fs/ceph/super.c:1042 ceph_umount_begin() warn: variable dereferenced before check 'fsc' (see line 1041)
vim +/fsc +1042 fs/ceph/super.c
void ceph_umount_begin(struct super_block *sb)
{
struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb);
doutc(fsc->client, "starting forced umount\n");
^^^^^^^^^^^
Dereferenced
if (!fsc)
^^^^
Checked too late.
return;
fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
__ceph_umount_begin(fsc);
}
The VFS guarantees that the superblock is still
alive when it calls into ceph via ->umount_begin().
Finally, we don't need to check the fsc and
it should be valid. This patch simply removes
the fsc check.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202503280852.YDB3pxUY-lkp@intel.com/
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
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Merge tag 'vfs-6.16-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull netfs updates from Christian Brauner:
- The main API document has been extensively updated/rewritten
- Fix an oops in write-retry due to mis-resetting the I/O iterator
- Fix the recording of transferred bytes for short DIO reads
- Fix a request's work item to not require a reference, thereby
avoiding the need to get rid of it in BH/IRQ context
- Fix waiting and waking to be consistent about the waitqueue used
- Remove NETFS_SREQ_SEEK_DATA_READ, NETFS_INVALID_WRITE,
NETFS_ICTX_WRITETHROUGH, NETFS_READ_HOLE_CLEAR,
NETFS_RREQ_DONT_UNLOCK_FOLIOS, and NETFS_RREQ_BLOCKED
- Reorder structs to eliminate holes
- Remove netfs_io_request::ractl
- Only provide proc_link field if CONFIG_PROC_FS=y
- Remove folio_queue::marks3
- Fix undifferentiation of DIO reads from unbuffered reads
* tag 'vfs-6.16-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
netfs: Fix undifferentiation of DIO reads from unbuffered reads
netfs: Fix wait/wake to be consistent about the waitqueue used
netfs: Fix the request's work item to not require a ref
netfs: Fix setting of transferred bytes with short DIO reads
netfs: Fix oops in write-retry from mis-resetting the subreq iterator
fs/netfs: remove unused flag NETFS_RREQ_BLOCKED
fs/netfs: remove unused flag NETFS_RREQ_DONT_UNLOCK_FOLIOS
folio_queue: remove unused field `marks3`
fs/netfs: declare field `proc_link` only if CONFIG_PROC_FS=y
fs/netfs: remove `netfs_io_request.ractl`
fs/netfs: reorder struct fields to eliminate holes
fs/netfs: remove unused enum choice NETFS_READ_HOLE_CLEAR
fs/netfs: remove unused flag NETFS_ICTX_WRITETHROUGH
fs/netfs: remove unused source NETFS_INVALID_WRITE
fs/netfs: remove unused flag NETFS_SREQ_SEEK_DATA_READ
The CephFS kernel driver forgets to set the filesystem magic signature in
its superblock. As a result, IMA policy rules based on fsmagic matching do
not apply as intended. This causes a major performance regression in Talos
Linux [1] when mounting CephFS volumes, such as when deploying Rook Ceph
[2]. Talos Linux ships a hardened kernel with the following IMA policy
(irrelevant lines omitted):
[...]
dont_measure fsmagic=0xc36400 # CEPH_SUPER_MAGIC
[...]
measure func=FILE_CHECK mask=^MAY_READ euid=0
measure func=FILE_CHECK mask=^MAY_READ uid=0
[...]
Currently, IMA compares 0xc36400 == 0x0 for CephFS files, resulting in all
files opened with O_RDONLY or O_RDWR getting measured with SHA512 on every
open(2):
10 69990c87e8af323d47e2d6ae4... ima-ng sha512:<hash> /data/cephfs/test-file
Since O_WRONLY is rare, this results in an order of magnitude lower
performance than expected for practically all file operations. Properly
setting CEPH_SUPER_MAGIC in the CephFS superblock resolves the regression.
Tests performed on a 3x replicated Ceph v19.3.0 cluster across three
i5-7200U nodes each equipped with one Micron 7400 MAX M.2 disk (BlueStore)
and Gigabit ethernet, on Talos Linux v1.10.2:
FS-Mark 3.3
Test: 500 Files, Empty
Files/s > Higher Is Better
6.12.27-talos . 16.6 |====
+twelho patch . 208.4 |====================================================
FS-Mark 3.3
Test: 500 Files, 1KB Size
Files/s > Higher Is Better
6.12.27-talos . 15.6 |=======
+twelho patch . 118.6 |====================================================
FS-Mark 3.3
Test: 500 Files, 32 Sub Dirs, 1MB Size
Files/s > Higher Is Better
6.12.27-talos . 12.7 |===============
+twelho patch . 44.7 |=====================================================
IO500 [3] 2fcd6d6 results (benchmarks within variance omitted):
| IO500 benchmark | 6.12.27-talos | +twelho patch | Speedup |
|-------------------|----------------|----------------|-----------|
| mdtest-easy-write | 0.018524 kIOPS | 1.135027 kIOPS | 6027.33 % |
| mdtest-hard-write | 0.018498 kIOPS | 0.973312 kIOPS | 5161.71 % |
| ior-easy-read | 0.064727 GiB/s | 0.155324 GiB/s | 139.97 % |
| mdtest-hard-read | 0.018246 kIOPS | 0.780800 kIOPS | 4179.29 % |
This applies outside of synthetic benchmarks as well, for example, the time
to rsync a 55 MiB directory with ~12k of mostly small files drops from an
unusable 10m5s to a reasonable 26s (23x the throughput).
[1]: https://www.talos.dev/
[2]: https://www.talos.dev/v1.10/kubernetes-guides/configuration/ceph-with-rook/
[3]: https://github.com/IO500/io500
Cc: stable@vger.kernel.org
Signed-off-by: Dennis Marttinen <twelho@welho.tech>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The ceph/export.c contains very confusing logic of file handle size
calculation based on hardcoded values. This patch makes the cleanup of
this logic by means of introduction the named constants.
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
In 'ceph_zero_objects', promote 'object_size' to 'u64' to avoid possible
integer overflow.
Compile tested only.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Dmitry Kandybka <d.kandybka@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
On cifs, "DIO reads" (specified by O_DIRECT) need to be differentiated from
"unbuffered reads" (specified by cache=none in the mount parameters). The
difference is flagged in the protocol and the server may behave
differently: Windows Server will, for example, mandate that DIO reads are
block aligned.
Fix this by adding a NETFS_UNBUFFERED_READ to differentiate this from
NETFS_DIO_READ, parallelling the write differentiation that already exists.
cifs will then do the right thing.
Fixes: 016dc8516a ("netfs: Implement unbuffered/DIO read support")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/3444961.1747987072@warthog.procyon.org.uk
Reviewed-by: "Paulo Alcantara (Red Hat)" <pc@manguebit.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
cc: Steve French <sfrench@samba.org>
cc: netfs@lists.linux.dev
cc: v9fs@lists.linux.dev
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
When the netfs_io_request struct's work item is queued, it must be supplied
with a ref to the work item struct to prevent it being deallocated whilst
on the queue or whilst it is being processed. This is tricky to manage as
we have to get a ref before we try and queue it and then we may find it's
already queued and is thus already holding a ref - in which case we have to
try and get rid of the ref again.
The problem comes if we're in BH or IRQ context and need to drop the ref:
if netfs_put_request() reduces the count to 0, we have to do the cleanup -
but the cleanup may need to wait.
Fix this by adding a new work item to the request, ->cleanup_work, and
dispatching that when the refcount hits zero. That can then synchronously
cancel any outstanding work on the main work item before doing the cleanup.
Adding a new work item also deals with another problem upstream where it's
sometimes changing the work func in the put function and requeuing it -
which has occasionally in the past caused the cleanup to happen
incorrectly.
As a bonus, this allows us to get rid of the 'was_async' parameter from a
bunch of functions. This indicated whether the put function might not be
permitted to sleep.
Fixes: 3d3c950467 ("netfs: Provide readahead and readpage netfs helpers")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519090707.2848510-4-dhowells@redhat.com
cc: Paulo Alcantara <pc@manguebit.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Steve French <stfrench@microsoft.com>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
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Merge tag 'ceph-for-6.15-rc4' of https://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
"A small CephFS encryption-related fix and a dead code cleanup"
* tag 'ceph-for-6.15-rc4' of https://github.com/ceph/ceph-client:
ceph: Fix incorrect flush end position calculation
ceph: Remove osd_client deadcode
Now that LIBCRC32C does nothing besides select CRC32, make every option
that selects LIBCRC32C instead select CRC32 directly. Then remove
LIBCRC32C.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250401221600.24878-8-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
In ceph, in fill_fscrypt_truncate(), the end flush position is calculated
by:
loff_t lend = orig_pos + CEPH_FSCRYPT_BLOCK_SHIFT - 1;
but that's using the block shift not the block size.
Fix this to use the block size instead.
Fixes: 5c64737d25 ("ceph: add truncate size handling support for fscrypt")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
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Merge tag 'vfs-6.15-rc1.ceph' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs ceph updates from Christian Brauner:
"This contains the work to remove access to page->index from ceph
and fixes the test failure observed for ceph with generic/421 by
refactoring ceph_writepages_start()"
* tag 'vfs-6.15-rc1.ceph' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fscrypt: Change fscrypt_encrypt_pagecache_blocks() to take a folio
ceph: Fix error handling in fill_readdir_cache()
fs: Remove page_mkwrite_check_truncate()
ceph: Pass a folio to ceph_allocate_page_array()
ceph: Convert ceph_move_dirty_page_in_page_array() to move_dirty_folio_in_page_array()
ceph: Remove uses of page from ceph_process_folio_batch()
ceph: Convert ceph_check_page_before_write() to use a folio
ceph: Convert writepage_nounlock() to write_folio_nounlock()
ceph: Convert ceph_readdir_cache_control to store a folio
ceph: Convert ceph_find_incompatible() to take a folio
ceph: Use a folio in ceph_page_mkwrite()
ceph: Remove ceph_writepage()
ceph: fix generic/421 test failure
ceph: introduce ceph_submit_write() method
ceph: introduce ceph_process_folio_batch() method
ceph: extend ceph_writeback_ctl for ceph_writepages_start() refactoring
ext4 and ceph already have a folio to pass; f2fs needs to be properly
converted but this will do for now. This removes a reference
to page->index and page->mapping as well as removing a call to
compound_head().
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250304170224.523141-1-willy@infradead.org
Acked-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
__filemap_get_folio() returns an ERR_PTR, not NULL. There are extensive
assumptions that ctl->folio is NULL, not an error pointer, so it seems
better to fix this one place rather than change all the places which
check ctl->folio.
Fixes: baff9740bc ("ceph: Convert ceph_readdir_cache_control to store a folio")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250304154818.250757-1-willy@infradead.org
Cc: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Shorten the name of this internal function by dropping the 'ceph_'
prefix and pass in a folio instead of a page.
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-9-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Remove uses of page->index and deprecated page APIs. Saves a lot of
hidden calls to compound_head().
Also convert is_page_index_contiguous() to is_folio_index_contiguous()
and make its arguments const.
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-8-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Remove the conversion back to a struct page and just use the folio
passed in.
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-7-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Remove references to page->index, page->mapping, thp_size(),
page_offset() and other page APIs in favour of their more efficient
folio replacements.
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-6-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pass a folio around instead of a page. This removes an access to
page->index and a few hidden calls to compound_head().
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-5-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Both callers already have the folio. Pass it in and use it throughout.
Removes some hidden calls to compound_head() and a reference to
page->mapping.
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-4-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Convert the passed page to a folio and use it
throughout ceph_page_mkwrite(). Removes the last call to
page_mkwrite_check_truncate(), the last call to offset_in_thp() and one
of the last calls to thp_size(). Saves a few calls to compound_head().
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-3-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Ceph already has a writepages operation which is preferred over writepage
in all situations except for page migration. By adding a migrate_folio
operation, there will be no situations in which ->writepage should
be called. filemap_migrate_folio() is an appropriate operation to use
because the ceph data stored in folio->private does not contain any
reference to the memory address of the folio.
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-2-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The generic/421 fails to finish because of the issue:
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.894678] INFO: task kworker/u48:0:11 blocked for more than 122 seconds.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895403] Not tainted 6.13.0-rc5+ #1
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895867] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896633] task:kworker/u48:0 state:D stack:0 pid:11 tgid:11 ppid:2 flags:0x00004000
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896641] Workqueue: writeback wb_workfn (flush-ceph-24)
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897614] Call Trace:
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897620] <TASK>
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897629] __schedule+0x443/0x16b0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897637] schedule+0x2b/0x140
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897640] io_schedule+0x4c/0x80
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897643] folio_wait_bit_common+0x11b/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897646] ? _raw_spin_unlock_irq+0xe/0x50
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897652] ? __pfx_wake_page_function+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897655] __folio_lock+0x17/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897658] ceph_writepages_start+0xca9/0x1fb0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897663] ? fsnotify_remove_queued_event+0x2f/0x40
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897668] do_writepages+0xd2/0x240
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897672] __writeback_single_inode+0x44/0x350
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897675] writeback_sb_inodes+0x25c/0x550
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897680] wb_writeback+0x89/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897683] ? finish_task_switch.isra.0+0x97/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897687] wb_workfn+0xb5/0x410
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897689] process_one_work+0x188/0x3d0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897692] worker_thread+0x2b5/0x3c0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897694] ? __pfx_worker_thread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897696] kthread+0xe1/0x120
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897699] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897701] ret_from_fork+0x43/0x70
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897705] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897707] ret_from_fork_asm+0x1a/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897711] </TASK>
There are several issues here:
(1) ceph_kill_sb() doesn't wait ending of flushing
all dirty folios/pages because of racy nature of
mdsc->stopping_blockers. As a result, mdsc->stopping
becomes CEPH_MDSC_STOPPING_FLUSHED too early.
(2) The ceph_inc_osd_stopping_blocker(fsc->mdsc) fails
to increment mdsc->stopping_blockers. Finally,
already locked folios/pages are never been unlocked
and the logic tries to lock the same page second time.
(3) The folio_batch with found dirty pages by
filemap_get_folios_tag() is not processed properly.
And this is why some number of dirty pages simply never
processed and we have dirty folios/pages after unmount
anyway.
This patch fixes the issues by means of:
(1) introducing dirty_folios counter and flush_end_wq
waiting queue in struct ceph_mds_client;
(2) ceph_dirty_folio() increments the dirty_folios
counter;
(3) writepages_finish() decrements the dirty_folios
counter and wake up all waiters on the queue
if dirty_folios counter is equal or lesser than zero;
(4) adding in ceph_kill_sb() method the logic of
checking the value of dirty_folios counter and
waiting if it is bigger than zero;
(5) adding ceph_inc_osd_stopping_blocker() call in the
beginning of the ceph_writepages_start() and
ceph_dec_osd_stopping_blocker() at the end of
the ceph_writepages_start() with the goal to resolve
the racy nature of mdsc->stopping_blockers.
sudo ./check generic/421
FSTYP -- ceph
PLATFORM -- Linux/x86_64 ceph-testing-0001 6.13.0+ #137 SMP PREEMPT_DYNAMIC Mon Feb 3 20:30:08 UTC 2025
MKFS_OPTIONS -- 127.0.0.1:40551:/scratch
MOUNT_OPTIONS -- -o name=fs,secret=<secret>,ms_mode=crc,nowsync,copyfrom 127.0.0.1:40551:/scratch /mnt/scratch
generic/421 7s ... 4s
Ran: generic/421
Passed all 1 tests
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-5-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Final responsibility of ceph_writepages_start() is
to submit write requests for processed dirty folios/pages.
The ceph_submit_write() summarize all this logic in
one method.
The generic/421 fails to finish because of the issue:
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.894678] INFO: task kworker/u48:0:11 blocked for more than 122 seconds.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895403] Not tainted 6.13.0-rc5+ #1
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895867] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896633] task:kworker/u48:0 state:D stack:0 pid:11 tgid:11 ppid:2 flags:0x00004000
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896641] Workqueue: writeback wb_workfn (flush-ceph-24)
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897614] Call Trace:
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897620] <TASK>
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897629] __schedule+0x443/0x16b0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897637] schedule+0x2b/0x140
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897640] io_schedule+0x4c/0x80
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897643] folio_wait_bit_common+0x11b/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897646] ? _raw_spin_unlock_irq+0xe/0x50
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897652] ? __pfx_wake_page_function+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897655] __folio_lock+0x17/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897658] ceph_writepages_start+0xca9/0x1fb0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897663] ? fsnotify_remove_queued_event+0x2f/0x40
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897668] do_writepages+0xd2/0x240
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897672] __writeback_single_inode+0x44/0x350
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897675] writeback_sb_inodes+0x25c/0x550
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897680] wb_writeback+0x89/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897683] ? finish_task_switch.isra.0+0x97/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897687] wb_workfn+0xb5/0x410
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897689] process_one_work+0x188/0x3d0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897692] worker_thread+0x2b5/0x3c0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897694] ? __pfx_worker_thread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897696] kthread+0xe1/0x120
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897699] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897701] ret_from_fork+0x43/0x70
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897705] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897707] ret_from_fork_asm+0x1a/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897711] </TASK>
There are two problems here:
if (!ceph_inc_osd_stopping_blocker(fsc->mdsc)) {
rc = -EIO;
goto release_folios;
}
(1) ceph_kill_sb() doesn't wait ending of flushing
all dirty folios/pages because of racy nature of
mdsc->stopping_blockers. As a result, mdsc->stopping
becomes CEPH_MDSC_STOPPING_FLUSHED too early.
(2) The ceph_inc_osd_stopping_blocker(fsc->mdsc) fails
to increment mdsc->stopping_blockers. Finally,
already locked folios/pages are never been unlocked
and the logic tries to lock the same page second time.
This patch implements refactoring of ceph_submit_write()
and also it solves the second issue.
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-4-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
First step of ceph_writepages_start() logic is
of finding the dirty memory folios and processing it.
This patch introduces ceph_process_folio_batch()
method that moves this logic into dedicated method.
The ceph_writepages_start() has this logic:
if (ceph_wbc.locked_pages == 0)
lock_page(page); /* first page */
else if (!trylock_page(page))
break;
<skipped>
if (folio_test_writeback(folio) ||
folio_test_private_2(folio) /* [DEPRECATED] */) {
if (wbc->sync_mode == WB_SYNC_NONE) {
doutc(cl, "%p under writeback\n", folio);
folio_unlock(folio);
continue;
}
doutc(cl, "waiting on writeback %p\n", folio);
folio_wait_writeback(folio);
folio_wait_private_2(folio); /* [DEPRECATED] */
}
The problem here that folio/page is locked here at first
and it is by set_page_writeback(page) later before
submitting the write request. The folio/page is unlocked
by writepages_finish() after finishing the write
request. It means that logic of checking folio_test_writeback()
and folio_wait_writeback() never works because page is locked
and it cannot be locked again until write request completion.
However, for majority of folios/pages the trylock_page()
is used. As a result, multiple threads can try to lock the same
folios/pages multiple times even if they are under writeback
already. It makes this logic more compute intensive than
it is necessary.
This patch changes this logic:
if (folio_test_writeback(folio) ||
folio_test_private_2(folio) /* [DEPRECATED] */) {
if (wbc->sync_mode == WB_SYNC_NONE) {
doutc(cl, "%p under writeback\n", folio);
folio_unlock(folio);
continue;
}
doutc(cl, "waiting on writeback %p\n", folio);
folio_wait_writeback(folio);
folio_wait_private_2(folio); /* [DEPRECATED] */
}
if (ceph_wbc.locked_pages == 0)
lock_page(page); /* first page */
else if (!trylock_page(page))
break;
This logic should exclude the ignoring of writeback
state of folios/pages.
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-3-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The ceph_writepages_start() has unreasonably huge size and
complex logic that makes this method hard to understand.
Current state of the method's logic makes bug fix really
hard task. This patch extends the struct ceph_writeback_ctl
with the goal to make ceph_writepages_start() method
more compact and easy to understand by means of deep refactoring.
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-2-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
ceph already splices the correct dentry (in splice_dentry()) from the
result of mkdir but does nothing more with it.
Now that ->mkdir can return a dentry, return the correct dentry.
Note that previously ceph_mkdir() could call
ceph_init_inode_acls()
on the inode from the wrong dentry, which would be NULL. This
is safe as ceph_init_inode_acls() checks for NULL, but is not
strictly correct. With this patch, the inode for the returned dentry
is passed to ceph_init_inode_acls().
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20250227013949.536172-4-neilb@suse.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
Some filesystems, such as NFS, cifs, ceph, and fuse, do not have
complete control of sequencing on the actual filesystem (e.g. on a
different server) and may find that the inode created for a mkdir
request already exists in the icache and dcache by the time the mkdir
request returns. For example, if the filesystem is mounted twice the
directory could be visible on the other mount before it is on the
original mount, and a pair of name_to_handle_at(), open_by_handle_at()
calls could instantiate the directory inode with an IS_ROOT() dentry
before the first mkdir returns.
This means that the dentry passed to ->mkdir() may not be the one that
is associated with the inode after the ->mkdir() completes. Some
callers need to interact with the inode after the ->mkdir completes and
they currently need to perform a lookup in the (rare) case that the
dentry is no longer hashed.
This lookup-after-mkdir requires that the directory remains locked to
avoid races. Planned future patches to lock the dentry rather than the
directory will mean that this lookup cannot be performed atomically with
the mkdir.
To remove this barrier, this patch changes ->mkdir to return the
resulting dentry if it is different from the one passed in.
Possible returns are:
NULL - the directory was created and no other dentry was used
ERR_PTR() - an error occurred
non-NULL - this other dentry was spliced in
This patch only changes file-systems to return "ERR_PTR(err)" instead of
"err" or equivalent transformations. Subsequent patches will make
further changes to some file-systems to return a correct dentry.
Not all filesystems reliably result in a positive hashed dentry:
- NFS, cifs, hostfs will sometimes need to perform a lookup of
the name to get inode information. Races could result in this
returning something different. Note that this lookup is
non-atomic which is what we are trying to avoid. Placing the
lookup in filesystem code means it only happens when the filesystem
has no other option.
- kernfs and tracefs leave the dentry negative and the ->revalidate
operation ensures that lookup will be called to correctly populate
the dentry. This could be fixed but I don't think it is important
to any of the users of vfs_mkdir() which look at the dentry.
The recommendation to use
d_drop();d_splice_alias()
is ugly but fits with current practice. A planned future patch will
change this.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20250227013949.536172-2-neilb@suse.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
cleanups from Liang and Slava, all in CephFS.
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Merge tag 'ceph-for-6.14-rc1' of https://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
"A fix for a memory leak from Antoine (marked for stable) and two
cleanups from Liang and Slava"
* tag 'ceph-for-6.14-rc1' of https://github.com/ceph/ceph-client:
ceph: exchange hardcoded value on NAME_MAX
ceph: streamline request head structures in MDS client
ceph: fix memory leak in ceph_mds_auth_match()
Most of the filesystem methods where we care about dentry name
and parent have their stability guaranteed by the callers;
->d_revalidate() is the major exception.
It's easy enough for callers to supply stable values for
expected name and expected parent of the dentry being
validated. That kills quite a bit of boilerplate in
->d_revalidate() instances, along with a bunch of races
where they used to access ->d_name without sufficient
precautions.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs d_revalidate updates from Al Viro:
"Provide stable parent and name to ->d_revalidate() instances
Most of the filesystem methods where we care about dentry name and
parent have their stability guaranteed by the callers;
->d_revalidate() is the major exception.
It's easy enough for callers to supply stable values for expected name
and expected parent of the dentry being validated. That kills quite a
bit of boilerplate in ->d_revalidate() instances, along with a bunch
of races where they used to access ->d_name without sufficient
precautions"
* tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
9p: fix ->rename_sem exclusion
orangefs_d_revalidate(): use stable parent inode and name passed by caller
ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller
nfs: fix ->d_revalidate() UAF on ->d_name accesses
nfs{,4}_lookup_validate(): use stable parent inode passed by caller
gfs2_drevalidate(): use stable parent inode and name passed by caller
fuse_dentry_revalidate(): use stable parent inode and name passed by caller
vfat_revalidate{,_ci}(): use stable parent inode passed by caller
exfat_d_revalidate(): use stable parent inode passed by caller
fscrypt_d_revalidate(): use stable parent inode passed by caller
ceph_d_revalidate(): propagate stable name down into request encoding
ceph_d_revalidate(): use stable parent inode passed by caller
afs_d_revalidate(): use stable name and parent inode passed by caller
Pass parent directory inode and expected name to ->d_revalidate()
generic_ci_d_compare(): use shortname_storage
ext4 fast_commit: make use of name_snapshot primitives
dissolve external_name.u into separate members
make take_dentry_name_snapshot() lockless
dcache: back inline names with a struct-wrapped array of unsigned long
make sure that DNAME_INLINE_LEN is a multiple of word size
Currently get_fscrypt_altname() requires ->r_dentry->d_name to be stable
and it gets that in almost all cases. The only exception is ->d_revalidate(),
where we have a stable name, but it's passed separately - dentry->d_name
is not stable there.
Propagate it down to get_fscrypt_altname() as a new field of struct
ceph_mds_request - ->r_dname, to be used instead ->r_dentry->d_name
when non-NULL.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
No need to mess with the boilerplate for obtaining what we already
have. Note that ceph is one of the "will want a path from filesystem
root if we want to talk to server" cases, so the name of the last
component is of little use - it is passed to fscrypt_d_revalidate()
and it's used to deal with (also crypt-related) case in request
marshalling, when encrypted name turns out to be too long. The former
is not a problem, but the latter is racy; that part will be handled
in the next commit.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
->d_revalidate() often needs to access dentry parent and name; that has
to be done carefully, since the locking environment varies from caller
to caller. We are not guaranteed that dentry in question will not be
moved right under us - not unless the filesystem is such that nothing
on it ever gets renamed.
It can be dealt with, but that results in boilerplate code that isn't
even needed - the callers normally have just found the dentry via dcache
lookup and want to verify that it's in the right place; they already
have the values of ->d_parent and ->d_name stable. There is a couple
of exceptions (overlayfs and, to less extent, ecryptfs), but for the
majority of calls that song and dance is not needed at all.
It's easier to make ecryptfs and overlayfs find and pass those values if
there's a ->d_revalidate() instance to be called, rather than doing that
in the instances.
This commit only changes the calling conventions; making use of supplied
values is left to followups.
NOTE: some instances need more than just the parent - things like CIFS
may need to build an entire path from filesystem root, so they need
more precautions than the usual boilerplate. This series doesn't
do anything to that need - these filesystems have to keep their locking
mechanisms (rename_lock loops, use of dentry_path_raw(), private rwsem
a-la v9fs).
One thing to keep in mind when using name is that name->name will normally
point into the pathname being resolved; the filename in question occupies
name->len bytes starting at name->name, and there is NUL somewhere after it,
but it the next byte might very well be '/' rather than '\0'. Do not
ignore name->len.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Initially, ceph_fs_debugfs_init() had temporary
name buffer with hardcoded length of 80 symbols.
Then, it was hardcoded again for 100 symbols.
Finally, it makes sense to exchange hardcoded
value on properly defined constant and 255 symbols
should be enough for any name case.
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Patrick Donnelly <pdonnell@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>