kernel/linux.git/fs/ext4/ioctl.c, branch v6.19.11

ext4: mark group extend fast-commit ineligible

2026-03-04T12:20:25+00:00

[ Upstream commit 1f8dd813a1c771b13c303f73d876164bc9b327cc ] Fast commits only log operations that have dedicated replay support. EXT4_IOC_GROUP_EXTEND grows the filesystem to the end of the last block group and updates the same on-disk metadata without going through the fast commit tracking paths. In practice these operations are rare and usually followed by further updates, but mixing them into a fast commit makes the overall semantics harder to reason about and risks replay gaps if new call sites appear. Teach ext4 to mark the filesystem fast-commit ineligible when EXT4_IOC_GROUP_EXTEND grows the filesystem. This forces those transactions to fall back to a full commit, ensuring that the group extension changes are captured by the normal journal rather than partially encoded in fast commit TLVs. This change should not affect common workloads but makes online resize via GROUP_EXTEND safer and easier to reason about under fast commit. Testing: 1. prepare: dd if=/dev/zero of=/root/fc_resize.img bs=1M count=0 seek=256 mkfs.ext4 -O fast_commit -F /root/fc_resize.img mkdir -p /mnt/fc_resize && mount -t ext4 -o loop /root/fc_resize.img /mnt/fc_resize 2. Extended the filesystem to the end of the last block group using a helper that calls EXT4_IOC_GROUP_EXTEND on the mounted filesystem and checked fc_info: ./group_extend_helper /mnt/fc_resize cat /proc/fs/ext4/loop0/fc_info shows the "Resize" ineligible reason increased. 3. Fsynced a file on the resized filesystem and confirmed that the fast commit ineligible counter incremented for the resize transaction: touch /mnt/fc_resize/file /root/fsync_file /mnt/fc_resize/file sync cat /proc/fs/ext4/loop0/fc_info Signed-off-by: Li Chen Link: https://patch.msgid.link/20251211115146.897420-6-me@linux.beauty Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: mark group add fast-commit ineligible

2026-03-04T12:20:25+00:00

[ Upstream commit 89b4336fd5ec78f51f9d3a1d100f3ffa3228e604 ] Fast commits only log operations that have dedicated replay support. Online resize via EXT4_IOC_GROUP_ADD updates the superblock and group descriptor metadata without going through the fast commit tracking paths. In practice these operations are rare and usually followed by further updates, but mixing them into a fast commit makes the overall semantics harder to reason about and risks replay gaps if new call sites appear. Teach ext4 to mark the filesystem fast-commit ineligible when ext4_ioctl_group_add() adds new block groups. This forces those transactions to fall back to a full commit, ensuring that the filesystem geometry updates are captured by the normal journal rather than partially encoded in fast commit TLVs. This change should not affect common workloads but makes online resize via GROUP_ADD safer and easier to reason about under fast commit. Testing: 1. prepare: dd if=/dev/zero of=/root/fc_resize.img bs=1M count=0 seek=256 mkfs.ext4 -O fast_commit -F /root/fc_resize.img mkdir -p /mnt/fc_resize && mount -t ext4 -o loop /root/fc_resize.img /mnt/fc_resize 2. Ran a helper that issues EXT4_IOC_GROUP_ADD on the mounted filesystem and checked the resize ineligible reason: ./group_add_helper /mnt/fc_resize cat /proc/fs/ext4/loop0/fc_info shows "Resize": > 0. 3. Fsynced a file on the resized filesystem and verified that the fast commit stats report at least one ineligible commit: touch /mnt/fc_resize/file /root/fsync_file /mnt/fc_resize/file sync cat /proc/fs/ext4/loop0/fc_info shows fc stats ineligible > 0. Signed-off-by: Li Chen Link: https://patch.msgid.link/20251211115146.897420-5-me@linux.beauty Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: check if mount_opts is NUL-terminated in ext4_ioctl_set_tune_sb()

2025-11-26T22:05:39+00:00

params.mount_opts may come as potentially non-NUL-term string. Userspace is expected to pass a NUL-term string. Add an extra check to ensure this holds true. Note that further code utilizes strscpy_pad() so this is just for proper informing the user of incorrect data being provided. Found by Linux Verification Center (linuxtesting.org). Signed-off-by: Fedor Pchelkin Reviewed-by: Baokun Li Reviewed-by: Jan Kara Message-ID: <20251101160430.222297-2-pchelkin@ispras.ru> Signed-off-by: Theodore Ts'o Cc: stable@kernel.org

ext4: add mext_check_validity() to do basic check

2025-11-06T15:44:39+00:00

Currently, the basic validation checks during the move extent operation are scattered across __ext4_ioctl() and ext4_move_extents(), which makes the code somewhat disorganized. Introduce a new helper, mext_check_validity(), to handle these checks. This change involves only code relocation without any logical modifications. Signed-off-by: Zhang Yi Reviewed-by: Jan Kara Message-ID: <20251013015128.499308-7-yi.zhang@huaweicloud.com> Signed-off-by: Theodore Ts'o

ext4: implemet new ioctls to set and get superblock parameters

2025-09-26T12:36:08+00:00

Implement the EXT4_IOC_GET_TUNE_SB_PARAM and EXT4_IOC_SET_TUNE_SB_PARAM ioctls, which allow certains superblock parameters to be set while the file system is mounted, without needing write access to the block device. Reviewed-by: Darrick J. Wong Reviewed-by: Jan Kara Signed-off-by: Theodore Ts'o Message-ID: <20250916-tune2fs-v2-3-d594dc7486f0@mit.edu> Signed-off-by: Theodore Ts'o

tree-wide: s/struct fileattr/struct file_kattr/g

2025-07-04T14:14:39+00:00

Now that we expose struct file_attr as our uapi struct rename all the internal struct to struct file_kattr to clearly communicate that it is a kernel internal struct. This is similar to struct mount_{k}attr and others. Link: https://lore.kernel.org/20250703-restlaufzeit-baurecht-9ed44552b481@brauner Signed-off-by: Christian Brauner

ext4: remove sb argument from ext4_superblock_csum()

2025-05-20T14:31:12+00:00

Since ext4_superblock_csum() no longer uses its sb argument, remove it. Signed-off-by: Eric Biggers Reviewed-by: Baokun Li Link: https://patch.msgid.link/20250513053809.699974-3-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

ext4: remove sbi argument from ext4_chksum()

2025-05-20T14:31:12+00:00

Since ext4_chksum() no longer uses its sbi argument, remove it. Signed-off-by: Eric Biggers Reviewed-by: Baokun Li Link: https://patch.msgid.link/20250513053809.699974-2-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

ext4: prevent stale extent cache entries caused by concurrent get es_cache

2025-05-14T14:42:12+00:00

The EXT4_IOC_GET_ES_CACHE and EXT4_IOC_PRECACHE_EXTENTS currently invokes ext4_ext_precache() to preload the extent cache without holding the inode's i_rwsem. This can result in stale extent cache entries when competing with operations such as ext4_collapse_range() which calls ext4_ext_remove_space() or ext4_ext_shift_extents(). The problem arises when ext4_ext_remove_space() temporarily releases i_data_sem due to insufficient journal credits. During this interval, a concurrent EXT4_IOC_GET_ES_CACHE or EXT4_IOC_PRECACHE_EXTENTS may cache extent entries that are about to be deleted. As a result, these cached entries become stale and inconsistent with the actual extents. Loading the extents cache without holding the inode's i_rwsem or the mapping's invalidate_lock is not permitted besides during the writeback. Fix this by holding the i_rwsem during EXT4_IOC_GET_ES_CACHE and EXT4_IOC_PRECACHE_EXTENTS. Signed-off-by: Zhang Yi Link: https://patch.msgid.link/20250423085257.122685-6-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o

ext4: remove redundant function ext4_has_metadata_csum

2025-03-17T15:19:41+00:00

Since commit f2b4fa19647e ("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 Reviewed-by: Darrick J. Wong Link: https://patch.msgid.link/20250207031335.42637-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o