[PATCH 3.10 188/268] cancel the setfilesize transation when io error happen

[Willy Tarreau]

From: Zhaohongjiang <zhaohongjiang@xxxxxxxxxx>

commit 510c971aeaaebf0dce7a45d16dc3eb9eab1c8340 upstream.

Commit 5cb13dcd0fac071b45c4bebe1801a08ff0d89cad upstream.

When I ran xfstest/073 case, the remount process was blocked to wait
transactions to be zero. I found there was a io error happened, and
the setfilesize transaction was not released properly. We should add
the changes to cancel the io error in this case.

Reproduction steps:
1. dd if=/dev/zero of=xfs1.img bs=1M count=2048
2. mkfs.xfs xfs1.img
3. losetup -f ./xfs1.img /dev/loop0
4. mount -t xfs /dev/loop0 /home/test_dir/
5. mkdir /home/test_dir/test
6. mkfs.xfs -dfile,name=image,size=2g
7. mount -t xfs -o loop image /home/test_dir/test
8. cp a file bigger than 2g to /home/test_dir/test
9. mount -t xfs -o remount,ro /home/test_dir/test

[ dchinner: moved io error detection to xfs_setfilesize_ioend() after
  transaction context restoration. ]

[ nborisov: Adjusted context for 3.12 ]

Signed-off-by: Zhao Hongjiang <zhaohongjiang@xxxxxxxxxx>
Signed-off-by: Dave Chinner <david@xxxxxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
 fs/xfs/xfs_aops.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index cfbb4c1..d738a7b 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -158,6 +158,12 @@ xfs_setfilesize(
 	rwsem_acquire_read(&VFS_I(ip)->i_sb->s_writers.lock_map[SB_FREEZE_FS-1],
 			   0, 1, _THIS_IP_);
 
+	/* we abort the update if there was an IO error */
+	if (ioend->io_error) {
+		xfs_trans_cancel(tp, 0);
+		return ioend->io_error;
+	}
+
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
 	isize = xfs_new_eof(ip, ioend->io_offset + ioend->io_size);
 	if (!isize) {
@@ -213,14 +219,17 @@ xfs_end_io(
 		ioend->io_error = -EIO;
 		goto done;
 	}
-	if (ioend->io_error)
-		goto done;
 
 	/*
 	 * For unwritten extents we need to issue transactions to convert a
 	 * range to normal written extens after the data I/O has finished.
+	 * Detecting and handling completion IO errors is done individually
+	 * for each case as different cleanup operations need to be performed
+	 * on error.
 	 */
 	if (ioend->io_type == XFS_IO_UNWRITTEN) {
+		if (ioend->io_error)
+			goto done;
 		error = xfs_iomap_write_unwritten(ip, ioend->io_offset,
 						  ioend->io_size);
 	} else if (ioend->io_isdirect && xfs_ioend_is_append(ioend)) {
-- 
2.8.0.rc2.1.gbe9624a