[PATCH v2] fstests: generic/730: exclude btrfs for now

[Qu Wenruo <wqu@suse.com>]

The test case always fail for btrfs:

  generic/730       - output mismatch (see /home/adam/xfstests-dev/results//generic/730.out.bad)
    --- tests/generic/730.out	2024-04-25 18:13:45.203549435 +0930
    +++ /home/adam/xfstests-dev/results//generic/730.out.bad	2025-06-04 15:10:39.062430952 +0930
    @@ -1,2 +1 @@
     QA output created by 730
    -cat: -: Input/output error
    ...

The root reason is that, btrfs doesn't implement its blk_holder_ops when
opening a block device.
Thus when the underlying block device is marked dead, btrfs is never
going to know thus no way to shutdown (nor btrfs has a way to shutdown
either).

I'm trying to improve the situation, but until then just exlucde btrfs
from the test case for now.

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
Changelog:
v2:
- Update the root reason
  It's not the sb->s_op->shutdown, that is only for single device
  fs (through fs_bdev_mark_dead()).
  For a multi-devices fs, it should provide a blk_holder_ops when
  opening the block device.
---
 tests/generic/730 | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/generic/730 b/tests/generic/730
index 6251980e..cae6489f 100755
--- a/tests/generic/730
+++ b/tests/generic/730
@@ -26,6 +26,10 @@ _require_test
 _require_block_device $TEST_DEV
 _require_scsi_debug
 
+if [ "$FSTYP" = "btrfs" ]; then
+	_notrun "btrfs doesn't support per-fs shutdown yet"
+fi
+
 size=$(_small_fs_size_mb 256)
 SCSI_DEBUG_DEV=`_get_scsi_debug_dev 512 512 0 $size`
 test -b "$SCSI_DEBUG_DEV" || _notrun "Failed to initialize scsi debug device"
-- 
2.49.0