Pull ext4 updates from Ted Ts'o:
"New ext4 features:
- Add support so tune2fs can modify/update the superblock using an
ioctl, without needing write access to the block device
- Add support for 32-bit reserved uid's and gid's
Bug fixes:
- Fix potential warnings and other failures caused by corrupted /
fuzzed file systems
- Fail unaligned direct I/O write with EINVAL instead of silently
falling back to buffered I/O
- Correectly handle fsmap queries for metadata mappings
- Avoid journal stalls caused by writeback throttling
- Add some missing GFP_NOFAIL flags to avoid potential deadlocks
under extremem memory pressure
Cleanups:
- Remove obsolete EXT3 Kconfigs"
* tag 'ext4_for_linus-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix checks for orphan inodes
ext4: validate ea_ino and size in check_xattrs
ext4: guard against EA inode refcount underflow in xattr update
ext4: implemet new ioctls to set and get superblock parameters
ext4: add support for 32-bit default reserved uid and gid values
ext4: avoid potential buffer over-read in parse_apply_sb_mount_options()
ext4: fix an off-by-one issue during moving extents
ext4: increase i_disksize to offset + len in ext4_update_disksize_before_punch()
ext4: verify orphan file size is not too big
ext4: fail unaligned direct IO write with EINVAL
ext4: correctly handle queries for metadata mappings
ext4: increase IO priority of fastcommit
ext4: remove obsolete EXT3 config options
jbd2: increase IO priority of checkpoint
ext4: fix potential null deref in ext4_mb_init()
ext4: add ext4_sb_bread_nofail() helper function for ext4_free_branches()
ext4: replace min/max nesting with clamp()
fs: ext4: change GFP_KERNEL to GFP_NOFS to avoid deadlock
Pull vfs inode updates from Christian Brauner:
"This contains a series I originally wrote and that Eric brought over
the finish line. It moves out the i_crypt_info and i_verity_info
pointers out of 'struct inode' and into the fs-specific part of the
inode.
So now the few filesytems that actually make use of this pay the price
in their own private inode storage instead of forcing it upon every
user of struct inode.
The pointer for the crypt and verity info is simply found by storing
an offset to its address in struct fsverity_operations and struct
fscrypt_operations. This shrinks struct inode by 16 bytes.
I hope to move a lot more out of it in the future so that struct inode
becomes really just about very core stuff that we need, much like
struct dentry and struct file, instead of the dumping ground it has
become over the years.
On top of this are a various changes associated with the ongoing inode
lifetime handling rework that multiple people are pushing forward:
- Stop accessing inode->i_count directly in f2fs and gfs2. They
simply should use the __iget() and iput() helpers
- Make the i_state flags an enum
- Rework the iput() logic
Currently, if we are the last iput, and we have the I_DIRTY_TIME
bit set, we will grab a reference on the inode again and then mark
it dirty and then redo the put. This is to make sure we delay the
time update for as long as possible
We can rework this logic to simply dec i_count if it is not 1, and
if it is do the time update while still holding the i_count
reference
Then we can replace the atomic_dec_and_lock with locking the
->i_lock and doing atomic_dec_and_test, since we did the
atomic_add_unless above
- Add an icount_read() helper and convert everyone that accesses
inode->i_count directly for this purpose to use the helper
- Expand dump_inode() to dump more information about an inode helping
in debugging
- Add some might_sleep() annotations to iput() and associated
helpers"
* tag 'vfs-6.18-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fs: add might_sleep() annotation to iput() and more
fs: expand dump_inode()
inode: fix whitespace issues
fs: add an icount_read helper
fs: rework iput logic
fs: make the i_state flags an enum
fs: stop accessing ->i_count directly in f2fs and gfs2
fsverity: check IS_VERITY() in fsverity_cleanup_inode()
fs: remove inode::i_verity_info
btrfs: move verity info pointer to fs-specific part of inode
f2fs: move verity info pointer to fs-specific part of inode
ext4: move verity info pointer to fs-specific part of inode
fsverity: add support for info in fs-specific part of inode
fs: remove inode::i_crypt_info
ceph: move crypt info pointer to fs-specific part of inode
ubifs: move crypt info pointer to fs-specific part of inode
f2fs: move crypt info pointer to fs-specific part of inode
ext4: move crypt info pointer to fs-specific part of inode
fscrypt: add support for info in fs-specific part of inode
fscrypt: replace raw loads of info pointer with helper function
Pull misc vfs updates from Christian Brauner:
"This contains the usual selections of misc updates for this cycle.
Features:
- Add "initramfs_options" parameter to set initramfs mount options.
This allows to add specific mount options to the rootfs to e.g.,
limit the memory size
- Add RWF_NOSIGNAL flag for pwritev2()
Add RWF_NOSIGNAL flag for pwritev2. This flag prevents the SIGPIPE
signal from being raised when writing on disconnected pipes or
sockets. The flag is handled directly by the pipe filesystem and
converted to the existing MSG_NOSIGNAL flag for sockets
- Allow to pass pid namespace as procfs mount option
Ever since the introduction of pid namespaces, procfs has had very
implicit behaviour surrounding them (the pidns used by a procfs
mount is auto-selected based on the mounting process's active
pidns, and the pidns itself is basically hidden once the mount has
been constructed)
This implicit behaviour has historically meant that userspace was
required to do some special dances in order to configure the pidns
of a procfs mount as desired. Examples include:
* In order to bypass the mnt_too_revealing() check, Kubernetes
creates a procfs mount from an empty pidns so that user
namespaced containers can be nested (without this, the nested
containers would fail to mount procfs)
But this requires forking off a helper process because you cannot
just one-shot this using mount(2)
* Container runtimes in general need to fork into a container
before configuring its mounts, which can lead to security issues
in the case of shared-pidns containers (a privileged process in
the pidns can interact with your container runtime process)
While SUID_DUMP_DISABLE and user namespaces make this less of an
issue, the strict need for this due to a minor uAPI wart is kind
of unfortunate
Things would be much easier if there was a way for userspace to
just specify the pidns they want. So this pull request contains
changes to implement a new "pidns" argument which can be set
using fsconfig(2):
fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd);
fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0);
or classic mount(2) / mount(8):
// mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc
mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid");
Cleanups:
- Remove the last references to EXPORT_OP_ASYNC_LOCK
- Make file_remove_privs_flags() static
- Remove redundant __GFP_NOWARN when GFP_NOWAIT is used
- Use try_cmpxchg() in start_dir_add()
- Use try_cmpxchg() in sb_init_done_wq()
- Replace offsetof() with struct_size() in ioctl_file_dedupe_range()
- Remove vfs_ioctl() export
- Replace rwlock() with spinlock in epoll code as rwlock causes
priority inversion on preempt rt kernels
- Make ns_entries in fs/proc/namespaces const
- Use a switch() statement() in init_special_inode() just like we do
in may_open()
- Use struct_size() in dir_add() in the initramfs code
- Use str_plural() in rd_load_image()
- Replace strcpy() with strscpy() in find_link()
- Rename generic_delete_inode() to inode_just_drop() and
generic_drop_inode() to inode_generic_drop()
- Remove unused arguments from fcntl_{g,s}et_rw_hint()
Fixes:
- Document @name parameter for name_contains_dotdot() helper
- Fix spelling mistake
- Always return zero from replace_fd() instead of the file descriptor
number
- Limit the size for copy_file_range() in compat mode to prevent a
signed overflow
- Fix debugfs mount options not being applied
- Verify the inode mode when loading it from disk in minixfs
- Verify the inode mode when loading it from disk in cramfs
- Don't trigger automounts with RESOLVE_NO_XDEV
If openat2() was called with RESOLVE_NO_XDEV it didn't traverse
through automounts, but could still trigger them
- Add FL_RECLAIM flag to show_fl_flags() macro so it appears in
tracepoints
- Fix unused variable warning in rd_load_image() on s390
- Make INITRAMFS_PRESERVE_MTIME depend on BLK_DEV_INITRD
- Use ns_capable_noaudit() when determining net sysctl permissions
- Don't call path_put() under namespace semaphore in listmount() and
statmount()"
* tag 'vfs-6.18-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (38 commits)
fcntl: trim arguments
listmount: don't call path_put() under namespace semaphore
statmount: don't call path_put() under namespace semaphore
pid: use ns_capable_noaudit() when determining net sysctl permissions
fs: rename generic_delete_inode() and generic_drop_inode()
init: INITRAMFS_PRESERVE_MTIME should depend on BLK_DEV_INITRD
initramfs: Replace strcpy() with strscpy() in find_link()
initrd: Use str_plural() in rd_load_image()
initramfs: Use struct_size() helper to improve dir_add()
initrd: Fix unused variable warning in rd_load_image() on s390
fs: use the switch statement in init_special_inode()
fs/proc/namespaces: make ns_entries const
filelock: add FL_RECLAIM to show_fl_flags() macro
eventpoll: Replace rwlock with spinlock
selftests/proc: add tests for new pidns APIs
procfs: add "pidns" mount option
pidns: move is-ancestor logic to helper
openat2: don't trigger automounts with RESOLVE_NO_XDEV
namei: move cross-device check to __traverse_mounts
namei: remove LOOKUP_NO_XDEV check from handle_mounts
...
When orphan file feature is enabled, inode can be tracked as orphan
either in the standard orphan list or in the orphan file. The first can
be tested by checking ei->i_orphan list head, the second is recorded by
EXT4_STATE_ORPHAN_FILE inode state flag. There are several places where
we want to check whether inode is tracked as orphan and only some of
them properly check for both possibilities. Luckily the consequences are
mostly minor, the worst that can happen is that we track an inode as
orphan although we don't need to and e2fsck then complains (resulting in
occasional ext4/307 xfstest failures). Fix the problem by introducing a
helper for checking whether an inode is tracked as orphan and use it in
appropriate places.
Fixes: 4a79a98c7b ("ext4: Improve scalability of ext4 orphan file handling")
Cc: stable@kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Message-ID: <20250925123038.20264-2-jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Support for specifying the default user id and group id that is
allowed to use the reserved block space was added way back when Linux
only supported 16-bit uid's and gid's. (Yeah, that long ago.) It's
not a commonly used feature, but let's add support for 32-bit user and
group id's.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Message-ID: <20250916-tune2fs-v2-2-d594dc7486f0@mit.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Unlike other strings in the ext4 superblock, we rely on tune2fs to
make sure s_mount_opts is NUL terminated. Harden
parse_apply_sb_mount_options() by treating s_mount_opts as a potential
__nonstring.
Cc: stable@vger.kernel.org
Fixes: 8b67f04ab9 ("ext4: Add mount options in superblock")
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Message-ID: <20250916-tune2fs-v2-1-d594dc7486f0@mit.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The implicit __GFP_NOFAIL flag in ext4_sb_bread() was removed in commit
8a83ac5494 ("ext4: call bdev_getblk() from sb_getblk_gfp()"), meaning
the function can now fail under memory pressure.
Most callers of ext4_sb_bread() propagate the error to userspace and do not
remount the filesystem read-only. However, ext4_free_branches() handles
ext4_sb_bread() failure by remounting the filesystem read-only.
This implies that an ext3 filesystem (mounted via the ext4 driver) could be
forcibly remounted read-only due to a transient page allocation failure,
which is unacceptable.
To mitigate this, introduce a new helper function, ext4_sb_bread_nofail(),
which explicitly uses __GFP_NOFAIL, and use it in ext4_free_branches().
Fixes: 8a83ac5494 ("ext4: call bdev_getblk() from sb_getblk_gfp()")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
generic_delete_inode() is rather misleading for what the routine is
doing. inode_just_drop() should be much clearer.
The new naming is inconsistent with generic_drop_inode(), so rename that
one as well with inode_ as the suffix.
No functional changes.
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Move the fsverity_info pointer into the filesystem-specific part of the
inode by adding the field ext4_inode_info::i_verity_info and configuring
fsverity_operations::inode_info_offs accordingly.
This is a prerequisite for a later commit that removes
inode::i_verity_info, saving memory and improving cache efficiency on
filesystems that don't support fsverity.
Co-developed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/20250810075706.172910-10-ebiggers@kernel.org
Acked-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Move the fscrypt_inode_info pointer into the filesystem-specific part of
the inode by adding the field ext4_inode_info::i_crypt_info and
configuring fscrypt_operations::inode_info_offs accordingly.
This is a prerequisite for a later commit that removes
inode::i_crypt_info, saving memory and improving cache efficiency with
filesystems that don't support fscrypt.
Co-developed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/20250810075706.172910-4-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Christian Brauner <brauner@kernel.org>
When the file system is frozen in preparation for taking an LVM
snapshot, the journal is checkpointed and if the orphan_file feature
is enabled, and the orphan file is empty, we clear the orphan_present
feature flag. But if there are pending inodes that need to be removed
the orphan_present feature flag can't be cleared.
The problem comes if the block device is read-only. In that case, we
can't process the orphan inode list, so it is skipped in
ext4_orphan_cleanup(). But then in ext4_mark_recovery_complete(),
this results in the ext4 error "Orphan file not empty on read-only fs"
firing and the file system mount is aborted.
Fix this by clearing the needs_recovery flag in the block device is
read-only. We do this after the call to ext4_load_and_init-journal()
since there are some error checks need to be done in case the journal
needs to be replayed and the block device is read-only, or if the
block device containing the externa journal is read-only, etc.
Cc: stable@kernel.org
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1108271
Cc: stable@vger.kernel.org
Fixes: 02f310fcf4 ("ext4: Speedup ext4 orphan inode handling")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
IMA testing revealed that after an ext4 remount, file accesses triggered
full measurements even without modifications, instead of skipping as
expected when i_version is unchanged.
Debugging showed `SB_I_VERSION` was cleared in reconfigure_super() during
remount due to commit 1ff2030739 ("ext4: unconditionally enable the
i_version counter") removing the fix from commit 960e0ab63b ("ext4: fix
i_version handling on remount").
To rectify this, `SB_I_VERSION` is always set for `fc->sb_flags` in
ext4_init_fs_context(), instead of `sb->s_flags` in __ext4_fill_super(),
ensuring it persists across all mounts.
Cc: stable@kernel.org
Fixes: 1ff2030739 ("ext4: unconditionally enable the i_version counter")
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250703073903.6952-2-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.
Conversion was done with coccinelle plus manual fixups where necessary.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, outside error paths, we auto commit the super block after 1
hour has passed and 16MB worth of updates have been written since last
commit. This is a policy decision so make this tunable while keeping the
defaults same. This is useful if user wants to tweak the superblock
behavior or for debugging the codepath by allowing to trigger it more
frequently.
We can now tweak the super block update using sb_update_sec and
sb_update_kb files in /sys/fs/ext4/<dev>/
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/950fb8c9b2905620e16f02a3b9eeea5a5b6cb87e.1742279837.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Presently we always BUG_ON if trying to start a transaction on a journal marked
with JBD2_UNMOUNT, since this should never happen. However, while ltp running
stress tests, it was observed that in case of some error handling paths, it is
possible for update_super_work to start a transaction after the journal is
destroyed eg:
(umount)
ext4_kill_sb
kill_block_super
generic_shutdown_super
sync_filesystem /* commits all txns */
evict_inodes
/* might start a new txn */
ext4_put_super
flush_work(&sbi->s_sb_upd_work) /* flush the workqueue */
jbd2_journal_destroy
journal_kill_thread
journal->j_flags |= JBD2_UNMOUNT;
jbd2_journal_commit_transaction
jbd2_journal_get_descriptor_buffer
jbd2_journal_bmap
ext4_journal_bmap
ext4_map_blocks
...
ext4_inode_error
ext4_handle_error
schedule_work(&sbi->s_sb_upd_work)
/* work queue kicks in */
update_super_work
jbd2_journal_start
start_this_handle
BUG_ON(journal->j_flags &
JBD2_UNMOUNT)
Hence, introduce a new mount flag to indicate journal is destroying and only do
a journaled (and deferred) update of sb if this flag is not set. Otherwise, just
fallback to an un-journaled commit.
Further, in the journal destroy path, we have the following sequence:
1. Set mount flag indicating journal is destroying
2. force a commit and wait for it
3. flush pending sb updates
This sequence is important as it ensures that, after this point, there is no sb
update that might be journaled so it is safe to update the sb outside the
journal. (To avoid race discussed in 2d01ddc866)
Also, we don't need a similar check in ext4_grp_locked_error since it is only
called from mballoc and AFAICT it would be always valid to schedule work here.
Fixes: 2d01ddc866 ("ext4: save error info to sb through journal if available")
Reported-by: Mahesh Kumar <maheshkumar657g@gmail.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/9613c465d6ff00cd315602f99283d5f24018c3f7.1742279837.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This fixes an analogus bug that was fixed in xfs in commit
4b8d867ca6 ("xfs: don't over-report free space or inodes in
statvfs") where statfs can report misleading / incorrect information
where project quota is enabled, and the free space is less than the
remaining quota.
This commit will resolve a test failure in generic/762 which tests for
this bug.
Cc: stable@kernel.org
Fixes: 689c958cbe ("ext4: add project quota support")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
commit 79add3a3f7 ("ext4: notify when discard is not supported")
noted that keeping the DISCARD flag is for possibility that the underlying
device might change in future even without file system remount. However,
this scenario has rarely occurred in practice on the device side. Even if
it does occur, it can be resolved with remount. Clearing the DISCARD flag
not only prevents confusion caused by mount options but also avoids
sending unnecessary discard commands.
Signed-off-by: Diangang Li <lidiangang@bytedance.com>
Link: https://patch.msgid.link/20250311021310.669524-1-lidiangang@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Since commit f2b4fa1964 ("ext4: switch to using the crc32c library"),
ext4_has_metadata_csum() is just an alias for
ext4_has_feature_metadata_csum(). ext4_has_feature_metadata_csum() is
generated by EXT4_FEATURE_RO_COMPAT_FUNCS and uses the regular naming
convention for checking a single ext4 feature. Therefore, remove
ext4_has_metadata_csum() and update all its callers to use
ext4_has_feature_metadata_csum() directly.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://patch.msgid.link/20250207031335.42637-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now, if dmesg is cleared, we have no way of knowing if the file system has
been shutdown. Moreover, ext4 allows directory reads even after the file
system has been shutdown, so when reading a file returns -EIO, we cannot
determine whether this is a hardware issue or if the file system has been
shutdown.
Therefore, when ext4 file system is shutdown, we're adding a 'shutdown'
hint to commands like mount so users can easily check the file system's
status.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250122114130.229709-8-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After commit d3476f3dad ("ext4: don't set SB_RDONLY after filesystem
errors") in v6.12-rc1, the 'errors=remount-ro' mode no longer sets
SB_RDONLY on errors, which results in us seeing the filesystem is still
in rw state after errors.
Therefore, after setting EXT4_FLAGS_EMERGENCY_RO, display the emergency_ro
option so that users can query whether the current file system has become
emergency read-only due to errors through commands such as 'mount' or
'cat /proc/fs/ext4/sdx/options'.
Fixes: d3476f3dad ("ext4: don't set SB_RDONLY after filesystem errors")
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250122114130.229709-7-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Since both SHUTDOWN and EMERGENCY_RO are emergency states of the ext4 file
system, and they are checked in similar locations, we have added a helper
function, ext4_emergency_state(), to determine whether the current file
system is in one of these two emergency states.
Then, replace calls to ext4_forced_shutdown() with ext4_emergency_state()
in those functions that could potentially trigger write operations.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20250122114130.229709-4-libaokun@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull fsnotify pre-content notification support from Jan Kara:
"This introduces a new fsnotify event (FS_PRE_ACCESS) that gets
generated before a file contents is accessed.
The event is synchronous so if there is listener for this event, the
kernel waits for reply. On success the execution continues as usual,
on failure we propagate the error to userspace. This allows userspace
to fill in file content on demand from slow storage. The context in
which the events are generated has been picked so that we don't hold
any locks and thus there's no risk of a deadlock for the userspace
handler.
The new pre-content event is available only for users with global
CAP_SYS_ADMIN capability (similarly to other parts of fanotify
functionality) and it is an administrator responsibility to make sure
the userspace event handler doesn't do stupid stuff that can DoS the
system.
Based on your feedback from the last submission, fsnotify code has
been improved and now file->f_mode encodes whether pre-content event
needs to be generated for the file so the fast path when nobody wants
pre-content event for the file just grows the additional file->f_mode
check. As a bonus this also removes the checks whether the old
FS_ACCESS event needs to be generated from the fast path. Also the
place where the event is generated during page fault has been moved so
now filemap_fault() generates the event if and only if there is no
uptodate folio in the page cache.
Also we have dropped FS_PRE_MODIFY event as current real-world users
of the pre-content functionality don't really use it so let's start
with the minimal useful feature set"
* tag 'fsnotify_hsm_for_v6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (21 commits)
fanotify: Fix crash in fanotify_init(2)
fs: don't block write during exec on pre-content watched files
fs: enable pre-content events on supported file systems
ext4: add pre-content fsnotify hook for DAX faults
btrfs: disable defrag on pre-content watched files
xfs: add pre-content fsnotify hook for DAX faults
fsnotify: generate pre-content permission event on page fault
mm: don't allow huge faults for files with pre content watches
fanotify: disable readahead if we have pre-content watches
fanotify: allow to set errno in FAN_DENY permission response
fanotify: report file range info with pre-content events
fanotify: introduce FAN_PRE_ACCESS permission event
fsnotify: generate pre-content permission event on truncate
fsnotify: pass optional file access range in pre-content event
fsnotify: introduce pre-content permission events
fanotify: reserve event bit of deprecated FAN_DIR_MODIFY
fanotify: rename a misnamed constant
fanotify: don't skip extra event info if no info_mode is set
fsnotify: check if file is actually being watched for pre-content events on open
fsnotify: opt-in for permission events at file open time
...
Pull ext4 updates from Ted Ts'o:
"A lot of miscellaneous ext4 bug fixes and cleanups this cycle, most
notably in the journaling code, bufered I/O, and compiler warning
cleanups"
* tag 'ext4_for_linus-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (33 commits)
jbd2: Fix comment describing journal_init_common()
ext4: prevent an infinite loop in the lazyinit thread
ext4: use struct_size() to improve ext4_htree_store_dirent()
ext4: annotate struct fname with __counted_by()
jbd2: avoid dozens of -Wflex-array-member-not-at-end warnings
ext4: use str_yes_no() helper function
ext4: prevent delalloc to nodelalloc on remount
jbd2: make b_frozen_data allocation always succeed
ext4: cleanup variable name in ext4_fc_del()
ext4: use string choices helpers
jbd2: remove the 'success' parameter from the jbd2_do_replay() function
jbd2: remove useless 'block_error' variable
jbd2: factor out jbd2_do_replay()
jbd2: refactor JBD2_COMMIT_BLOCK process in do_one_pass()
jbd2: unified release of buffer_head in do_one_pass()
jbd2: remove redundant judgments for check v1 checksum
ext4: use ERR_CAST to return an error-valued pointer
mm: zero range of eof folio exposed by inode size extension
ext4: partial zero eof block on unaligned inode size extension
ext4: disambiguate the return value of ext4_dio_write_end_io()
...
Pull vfs untorn write support from Christian Brauner:
"An atomic write is a write issed with torn-write protection. This
means for a power failure or any hardware failure all or none of the
data from the write will be stored, never a mix of old and new data.
This work is already supported for block devices. If a block device is
opened with O_DIRECT and the block device supports atomic write, then
FMODE_CAN_ATOMIC_WRITE is added to the file of the opened block
device.
This contains the work to expand atomic write support to filesystems,
specifically ext4 and XFS. Currently, only support for writing exactly
one filesystem block atomically is added.
Since it's now possible to have filesystem block size > page size for
XFS, it's possible to write 4K+ blocks atomically on x86"
* tag 'vfs-6.13.untorn.writes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
iomap: drop an obsolete comment in iomap_dio_bio_iter
ext4: Do not fallback to buffered-io for DIO atomic write
ext4: Support setting FMODE_CAN_ATOMIC_WRITE
ext4: Check for atomic writes support in write iter
ext4: Add statx support for atomic writes
xfs: Support setting FMODE_CAN_ATOMIC_WRITE
xfs: Validate atomic writes
xfs: Support atomic write for statx
fs: iomap: Atomic write support
fs: Export generic_atomic_write_valid()
block: Add bdev atomic write limits helpers
fs/block: Check for IOCB_DIRECT in generic_atomic_write_valid()
block/fs: Pass an iocb to generic_atomic_write_valid()
Use ktime_get_ns instead of ktime_get_real_ns when computing the lr_timeout
not to be affected by system time jumps.
Use a boolean instead of the MAX_JIFFY_OFFSET value to determine whether
the next_wakeup value has been set. Comparing elr->lr_next_sched to
MAX_JIFFY_OFFSET can cause the lazyinit thread to loop indefinitely.
Co-developed-by: Lukas Skupinski <lukas.skupinski@landisgyr.com>
Signed-off-by: Lukas Skupinski <lukas.skupinski@landisgyr.com>
Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20241106134741.26948-2-othacehe@gnu.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
