[PATCH v4 22/22] xfs: Support setting FMODE_CAN_ATOMIC_WRITE

John Garry
2024-06-07T14:41:10Z

For when an inode is enabled for atomic writes, set FMODE_CAN_ATOMIC_WRITE
flag. Only direct IO is currently supported, so check for that also.

We rely on the block layer to reject atomic writes which exceed the bdev
request_queue limits, so don't bother checking any such thing here.

Signed-off-by: John Garry <john.g.garry@oracle.com>
---
fs/xfs/xfs_file.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index eeb267ae2bf2..88ab743929fb 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1172,6 +1172,18 @@ xfs_file_remap_range(
return remapped > 0 ? remapped : ret;
}

+static bool xfs_file_open_can_atomicwrite(
+ struct inode *inode,
+ struct file *file)
+{
+ struct xfs_inode *ip = XFS_I(inode);
+
+ if (!(file->f_flags & O_DIRECT))
+ return false;
+
+ return xfs_inode_has_atomicwrites(ip);
+}
+
STATIC int
xfs_file_open(
struct inode *inode,
@@ -1180,6 +1192,8 @@ xfs_file_open(
if (xfs_is_shutdown(XFS_M(inode->i_sb)))
return -EIO;
file->f_mode |= FMODE_NOWAIT | FMODE_CAN_ODIRECT;
+ if (xfs_file_open_can_atomicwrite(inode, file))
+ file->f_mode |= FMODE_CAN_ATOMIC_WRITE;
return generic_file_open(inode, file);
}

--
2.31.1