| Message ID | 20250118-vfs-libfs-675d6c542bcc@brauner (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [GIT,PULL] vfs libfs | expand |
The pull request you sent on Sat, 18 Jan 2025 14:08:14 +0100:
> git@gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-6.14-rc1.libfs
has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/7e587c20adab5b8da4c7b5573e711a8c808e0a2d
Thank you!
Hey Linus, /* Summary */ This improves the stable directory offset behavior in various ways. Stable offsets are needed so that NFS can reliably read directories on filesystems such as tmpfs: - Improve the end-of-directory detection According to getdents(3), the d_off field in each returned directory entry points to the next entry in the directory. The d_off field in the last returned entry in the readdir buffer must contain a valid offset value, but if it points to an actual directory entry, then readdir/getdents can loop. Introduce a specific fixed offset value that is placed in the d_off field of the last entry in a directory. Some user space applications assume that the EOD offset value is larger than the offsets of real directory entries, so the largest valid offset value is reserved for this purpose. This new value is never allocated by simple_offset_add(). When ->iterate_dir() returns, getdents{64} inserts the ctx->pos value into the d_off field of the last valid entry in the readdir buffer. When it hits EOD, offset_readdir() sets ctx->pos to the EOD offset value so the last entry is updated to point to the EOD marker. When trying to read the entry at the EOD offset, offset_readdir() terminates immediately. - Rely on d_children to iterate stable offset directories Instead of using the mtree to emit entries in the order of their offset values, use it only to map incoming ctx->pos to a starting entry. Then use the directory's d_children list, which is already maintained properly by the dcache, to find the next child to emit. - Narrow the range of directory offset values returned by simple_offset_add() to 3 .. (S32_MAX - 1) on all platforms. This means the allocation behavior is identical on 32-bit systems, 64-bit systems, and 32-bit user space on 64-bit kernels. The new range still permits over 2 billion concurrent entries per directory. - Return ENOSPC when the directory offset range is exhausted. Hitting this error is almost impossible though. - Remove the simple_offset_empty() helper. /* Testing */ gcc version 14.2.0 (Debian 14.2.0-6) Debian clang version 16.0.6 (27+b1) No build failures or warnings were observed. /* Conflicts */ Merge conflicts with mainline ============================= No known conflicts. Merge conflicts with other trees ================================ No known conflicts. The following changes since commit 40384c840ea1944d7c5a392e8975ed088ecf0b37: Linux 6.13-rc1 (2024-12-01 14:28:56 -0800) are available in the Git repository at: git@gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-6.14-rc1.libfs for you to fetch changes up to a0634b457eca16b21a4525bc40cd2db80f52dadc: Merge patch series "Improve simple directory offset wrap behavior" (2025-01-04 10:15:58 +0100) Please consider pulling these changes from the signed vfs-6.14-rc1.libfs tag. Thanks! Christian ---------------------------------------------------------------- vfs-6.14-rc1.libfs ---------------------------------------------------------------- Christian Brauner (1): Merge patch series "Improve simple directory offset wrap behavior" Chuck Lever (5): libfs: Return ENOSPC when the directory offset range is exhausted Revert "libfs: Add simple_offset_empty()" Revert "libfs: fix infinite directory reads for offset dir" libfs: Replace simple_offset end-of-directory detection libfs: Use d_children list to iterate simple_offset directories fs/libfs.c | 162 +++++++++++++++++++++++++---------------------------- include/linux/fs.h | 1 - mm/shmem.c | 4 +- 3 files changed, 79 insertions(+), 88 deletions(-)