[PATCH 2/4] xfs: Switch atomic write size check in xfs_file_write_iter()

John Garry
2024-12-04T15:44:06Z

Currently atomic writes size permitted is fixed at the blocksize.

To start to remove this restriction, use xfs_get_atomic_write_attr() to
find the per-inode atomic write limits and check according to that.

Signed-off-by: John Garry <john.g.garry@oracle.com>
---
fs/xfs/xfs_file.c | 12 +++++-------
fs/xfs/xfs_iops.c | 2 +-
fs/xfs/xfs_iops.h | 2 ++
3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 4a0b7de4f7ae..abcaba71fea7 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -853,14 +853,12 @@ xfs_file_write_iter(
return xfs_file_dax_write(iocb, from);

if (iocb->ki_flags & IOCB_ATOMIC) {
- /*
- * Currently only atomic writing of a single FS block is
- * supported. It would be possible to atomic write smaller than
- * a FS block, but there is no requirement to support this.
- * Note that iomap also does not support this yet.
- */
- if (ocount != ip->i_mount->m_sb.sb_blocksize)
+ unsigned int unit_min, unit_max;
+
+ xfs_get_atomic_write_attr(ip, &unit_min, &unit_max);
+ if (ocount < unit_min || ocount > unit_max)
return -EINVAL;
+
ret = generic_atomic_write_valid(iocb, from);
if (ret)
return ret;
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 207e0dadffc3..883ec45ae708 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -572,7 +572,7 @@ xfs_stat_blksize(
return max_t(uint32_t, PAGE_SIZE, mp->m_sb.sb_blocksize);
}

-static void
+void
xfs_get_atomic_write_attr(
struct xfs_inode *ip,
unsigned int *unit_min,
diff --git a/fs/xfs/xfs_iops.h b/fs/xfs/xfs_iops.h
index 3c1a2605ffd2..82d3ffbf7024 100644
--- a/fs/xfs/xfs_iops.h
+++ b/fs/xfs/xfs_iops.h
@@ -19,5 +19,7 @@ int xfs_inode_init_security(struct inode *inode, struct inode *dir,
extern void xfs_setup_inode(struct xfs_inode *ip);
extern void xfs_setup_iops(struct xfs_inode *ip);
extern void xfs_diflags_to_iflags(struct xfs_inode *ip, bool init);
+extern void xfs_get_atomic_write_attr(struct xfs_inode *ip,
+ unsigned int *unit_min, unsigned int *unit_max);

#endif /* __XFS_IOPS_H__ */
--
2.31.1