diff options
| author | Prasad Singamsetty <prasad.singamsetty@oracle.com> | 2024-06-20 12:53:53 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2024-06-20 15:19:17 -0600 |
| commit | 0f9ca80fa4f9670ba09721e4e36b8baf086a500c (patch) | |
| tree | 4dfa63ee8a626a636988e878c9031ed0bb02a8ef /fs/stat.c | |
| parent | c34fc6f26ab86d03a2d47446f42b6cd492dfdc56 (diff) | |
fs: Add initial atomic write support info to statx
Extend statx system call to return additional info for atomic write support
support for a file.
Helper function generic_fill_statx_atomic_writes() can be used by FSes to
fill in the relevant statx fields. For now atomic_write_segments_max will
always be 1, otherwise some rules would need to be imposed on iovec length
and alignment, which we don't want now.
Signed-off-by: Prasad Singamsetty <prasad.singamsetty@oracle.com>
jpg: relocate bdev support to another patch
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20240620125359.2684798-5-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/stat.c')
| -rw-r--r-- | fs/stat.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/fs/stat.c b/fs/stat.c index 70bd3e888cfa..72d0e6357b91 100644 --- a/fs/stat.c +++ b/fs/stat.c @@ -90,6 +90,37 @@ void generic_fill_statx_attr(struct inode *inode, struct kstat *stat) EXPORT_SYMBOL(generic_fill_statx_attr); /** + * generic_fill_statx_atomic_writes - Fill in atomic writes statx attributes + * @stat: Where to fill in the attribute flags + * @unit_min: Minimum supported atomic write length in bytes + * @unit_max: Maximum supported atomic write length in bytes + * + * Fill in the STATX{_ATTR}_WRITE_ATOMIC flags in the kstat structure from + * atomic write unit_min and unit_max values. + */ +void generic_fill_statx_atomic_writes(struct kstat *stat, + unsigned int unit_min, + unsigned int unit_max) +{ + /* Confirm that the request type is known */ + stat->result_mask |= STATX_WRITE_ATOMIC; + + /* Confirm that the file attribute type is known */ + stat->attributes_mask |= STATX_ATTR_WRITE_ATOMIC; + + if (unit_min) { + stat->atomic_write_unit_min = unit_min; + stat->atomic_write_unit_max = unit_max; + /* Initially only allow 1x segment */ + stat->atomic_write_segments_max = 1; + + /* Confirm atomic writes are actually supported */ + stat->attributes |= STATX_ATTR_WRITE_ATOMIC; + } +} +EXPORT_SYMBOL_GPL(generic_fill_statx_atomic_writes); + +/** * vfs_getattr_nosec - getattr without security checks * @path: file to get attributes from * @stat: structure to return attributes in @@ -659,6 +690,9 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer) tmp.stx_dio_mem_align = stat->dio_mem_align; tmp.stx_dio_offset_align = stat->dio_offset_align; tmp.stx_subvol = stat->subvol; + tmp.stx_atomic_write_unit_min = stat->atomic_write_unit_min; + tmp.stx_atomic_write_unit_max = stat->atomic_write_unit_max; + tmp.stx_atomic_write_segments_max = stat->atomic_write_segments_max; return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0; } |