[PATCH v2] generic/250: ignore xfs_io IO errors when writing to dmerror device

[Eryu Guan <eguan@redhat.com>]

When testing with data=journal ext4, direct write to dmerror device
doesn't return EIO, because ext4 turns direct write to buffered write in
data=journal mode and all data is written to journal buffer. The write
only fails later when commiting journal and error messages can be seen
in dmesg.

As the test is checking on the md5 checksum of the test file, it's ok to
ignore the IO error returned by xfs_io, as long as the checksums match
the golden image.

Signed-off-by: Eryu Guan <eguan@redhat.com>
---

v2:
- Replace "CoW" with "Write" and update .out accordingly

 tests/generic/250     | 5 +++--
 tests/generic/250.out | 3 +--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/generic/250 b/tests/generic/250
index 6d15de2..3c4fe6d 100755
--- a/tests/generic/250
+++ b/tests/generic/250
@@ -79,11 +79,12 @@ _dmerror_mount
 echo "Compare files"
 md5sum $testdir/file2 | _filter_scratch
 
-echo "CoW and unmount"
+echo "Write and unmount"
 $XFS_IO_PROG -f -c "pwrite -S 0x63 $bufsize 1" $testdir/file2 >> $seqres.full
 sync
 _dmerror_load_error_table
-$XFS_IO_PROG -d -f -c "pwrite -S 0x63 -b $bufsize 0 $filesize" $testdir/file2 >> $seqres.full
+$XFS_IO_PROG -d -f -c "pwrite -S 0x63 -b $bufsize 0 $filesize" $testdir/file2 \
+	>> $seqres.full 2>&1
 _dmerror_load_working_table
 _dmerror_unmount
 _dmerror_mount
diff --git a/tests/generic/250.out b/tests/generic/250.out
index 710c80e..67b006b 100644
--- a/tests/generic/250.out
+++ b/tests/generic/250.out
@@ -3,8 +3,7 @@ Format and mount
 Create the original files
 Compare files
 ec8bb3b24d5b0f1b5bdf8c8f0f541ee6  SCRATCH_MNT/test-250/file2
-CoW and unmount
-pwrite64: Input/output error
+Write and unmount
 Compare files
 3ed86318f4ff8da26c1c2a6e3041f9be  SCRATCH_MNT/test-250/file2
 Check for damage
-- 
2.5.5