xfs: mark inodes dirty before issuing I/O

To make sure they get properly waited on in sync when I/O is in flight and
we latter need to update the inode size.  Requires a new helper to check if an
ioend structure is beyond the current EOF.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

fs/xfs/linux-2.6/xfs_aops.c

@@ -185,6 +185,24 @@ xfs_destroy_ioend(
 	mempool_free(ioend, xfs_ioend_pool);
 }
 
+/*
+ * If the end of the current ioend is beyond the current EOF,
+ * return the new EOF value, otherwise zero.
+ */
+STATIC xfs_fsize_t
+xfs_ioend_new_eof(
+	xfs_ioend_t		*ioend)
+{
+	xfs_inode_t		*ip = XFS_I(ioend->io_inode);
+	xfs_fsize_t		isize;
+	xfs_fsize_t		bsize;
+
+	bsize = ioend->io_offset + ioend->io_size;
+	isize = MAX(ip->i_size, ip->i_new_size);
+	isize = MIN(isize, bsize);
+	return isize > ip->i_d.di_size ? isize : 0;
+}
+
 /*
  * Update on-disk file size now that data has been written to disk.
  * The current in-memory file size is i_size.  If a write is beyond
@@ -192,13 +210,13 @@ xfs_destroy_ioend(
  * updated.  If this write does not extend all the way to the valid
  * file size then restrict this update to the end of the write.
  */
+
 STATIC void
 xfs_setfilesize(
 	xfs_ioend_t		*ioend)
 {
 	xfs_inode_t		*ip = XFS_I(ioend->io_inode);
 	xfs_fsize_t		isize;
-	xfs_fsize_t		bsize;
 
 	ASSERT((ip->i_d.di_mode & S_IFMT) == S_IFREG);
 	ASSERT(ioend->io_type != IOMAP_READ);
@@ -206,14 +224,9 @@ xfs_setfilesize(
 	if (unlikely(ioend->io_error))
 		return;
 
-	bsize = ioend->io_offset + ioend->io_size;
-
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
-
-	isize = MAX(ip->i_size, ip->i_new_size);
-	isize = MIN(isize, bsize);
-
-	if (ip->i_d.di_size < isize) {
+	isize = xfs_ioend_new_eof(ioend);
+	if (isize) {
 		ip->i_d.di_size = isize;
 		xfs_mark_inode_dirty_sync(ip);
 	}
@@ -403,10 +416,16 @@ xfs_submit_ioend_bio(
 	struct bio	*bio)
 {
 	atomic_inc(&ioend->io_remaining);
-
 	bio->bi_private = ioend;
 	bio->bi_end_io = xfs_end_bio;
 
+	/*
+	 * If the I/O is beyond EOF we mark the inode dirty immediately
+	 * but don't update the inode size until I/O completion.
+	 */
+	if (xfs_ioend_new_eof(ioend))
+		xfs_mark_inode_dirty_sync(XFS_I(ioend->io_inode));
+
 	submit_bio(WRITE, bio);
 	ASSERT(!bio_flagged(bio, BIO_EOPNOTSUPP));
 	bio_put(bio);