On 21/08/2024 18:11, Darrick J. Wong wrote:
On Sat, Aug 17, 2024 at 09:48:00AM +0000, John Garry wrote:
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@xxxxxxxxxx>
---
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 9b6530a4eb4a..3489d478809e 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1149,6 +1149,18 @@ 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);
...and here too. I do like the shift to having an incore flag that
controls whether you get untorn write support or not.
Do you mean that add a new member to xfs_inode to record this? If yes,
it sounds ok, but we need to maintain consistency (of that member)
whenever anything which can affect it changes, which is always a bit
painful.
John
