On Tue, Oct 24, 2017 at 05:24:14PM +0200, Jan Kara wrote:
From: Christoph Hellwig <hch(a)lst.de>
Return IOMAP_F_DIRTY from xfs_file_iomap_begin() when asked to prepare
blocks for writing and the inode is pinned, and has dirty fields other
than the timestamps.
That's "fdatasync dirty", not "fsync dirty".
IOMAP_F_DIRTY needs a far better description of it's semantics than
"/* block mapping is not yet on persistent storage */" so we know
exactly what filesystems are supposed to be implementing here. I
suspect that what it really is meant to say is:
* IOMAP_F_DIRTY indicates the inode has uncommitted metadata to
* written data and requires fdatasync to commit to persistent storage.
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index f179bdf1644d..b43be199fbdf 100644
@@ -33,6 +33,7 @@
@@ -1086,6 +1087,10 @@ xfs_file_iomap_begin(
trace_xfs_iomap_found(ip, offset, length, 0, &imap);
+ if ((flags & IOMAP_WRITE) && xfs_ipincount(ip) &&
+ (ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP))
+ iomap->flags |= IOMAP_F_DIRTY;
This is the very definition of an inode that is "fdatasync dirty".
Hmmmm, shouldn't this also be set for read faults, too?