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authorLinus Torvalds <torvalds@linux-foundation.org>2022-10-03 20:33:41 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-10-03 20:33:41 -0700
commit725737e7c21d2d25a4312c2aaa82a52bd03e3126 (patch)
tree85378eed2b05ec4c176afd8b0b33faab538084a3 /include/uapi/linux
parentMerge tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt (diff)
parentxfs: support STATX_DIOALIGN (diff)
downloadlinux-dev-725737e7c21d2d25a4312c2aaa82a52bd03e3126.tar.xz
linux-dev-725737e7c21d2d25a4312c2aaa82a52bd03e3126.zip
Merge tag 'statx-dioalign-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull STATX_DIOALIGN support from Eric Biggers: "Make statx() support reporting direct I/O (DIO) alignment information. This provides a generic interface for userspace programs to determine whether a file supports DIO, and if so with what alignment restrictions. Specifically, STATX_DIOALIGN works on block devices, and on regular files when their containing filesystem has implemented support. An interface like this has been requested for years, since the conditions for when DIO is supported in Linux have gotten increasingly complex over time. Today, DIO support and alignment requirements can be affected by various filesystem features such as multi-device support, data journalling, inline data, encryption, verity, compression, checkpoint disabling, log-structured mode, etc. Further complicating things, Linux v6.0 relaxed the traditional rule of DIO needing to be aligned to the block device's logical block size; now user buffers (but not file offsets) only need to be aligned to the DMA alignment. The approach of uplifting the XFS specific ioctl XFS_IOC_DIOINFO was discarded in favor of creating a clean new interface with statx(). For more information, see the individual commits and the man page update[1]" Link: https://lore.kernel.org/r/20220722074229.148925-1-ebiggers@kernel.org [1] * tag 'statx-dioalign-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: xfs: support STATX_DIOALIGN f2fs: support STATX_DIOALIGN f2fs: simplify f2fs_force_buffered_io() f2fs: move f2fs_force_buffered_io() into file.c ext4: support STATX_DIOALIGN fscrypt: change fscrypt_dio_supported() to prepare for STATX_DIOALIGN vfs: support STATX_DIOALIGN on block devices statx: add direct I/O alignment information
Diffstat (limited to 'include/uapi/linux')
-rw-r--r--include/uapi/linux/stat.h4
1 files changed, 3 insertions, 1 deletions
diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h
index 1500a0f58041..7cab2c65d3d7 100644
--- a/include/uapi/linux/stat.h
+++ b/include/uapi/linux/stat.h
@@ -124,7 +124,8 @@ struct statx {
__u32 stx_dev_minor;
/* 0x90 */
__u64 stx_mnt_id;
- __u64 __spare2;
+ __u32 stx_dio_mem_align; /* Memory buffer alignment for direct I/O */
+ __u32 stx_dio_offset_align; /* File offset alignment for direct I/O */
/* 0xa0 */
__u64 __spare3[12]; /* Spare space for future expansion */
/* 0x100 */
@@ -152,6 +153,7 @@ struct statx {
#define STATX_BASIC_STATS 0x000007ffU /* The stuff in the normal stat struct */
#define STATX_BTIME 0x00000800U /* Want/got stx_btime */
#define STATX_MNT_ID 0x00001000U /* Got stx_mnt_id */
+#define STATX_DIOALIGN 0x00002000U /* Want/got direct I/O alignment info */
#define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */