fstests: _require_dm_target should not always skip DAX capable devices

Recent changes have turned off all dm-error, dm-thin and dm-flakey
tests on pmem devices even when we are not explicitly testing DAX.
This is a regression resulting in a large number of log recovery
tests no longer running on my pmem-based test VMs. I added the "-o
dax=never" mount options to these test configs, only to find it
still would not run the dm tests even though the filesystem will
never use DAX.

Fix this so that the dm target DAX test explicitly ignores the
the block device DAX capability when the filesystem is mounted with
dax=never and hence we can use all the dm targets when the tests are
being run with FSDAX disabled.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

diff --git a/common/rc b/common/rc
index 7f693d3922e8e3e6ad9d172d41a9a40fb95007a4..751974539e6285388631c2612c7d99aec217c011 100644 (file)
--- a/common/rc
+++ b/common/rc
@@ -1965,12 +1965,19 @@ _require_sane_bdev_flush()
 }
 
 # Decide if the scratch filesystem is likely to be mounted in fsdax mode.
-# If there's a dax clause in the mount options we assume the test runner
-# wants us to test DAX; or if the scratch device itself advertises dax mode
-# in sysfs.
-__detect_scratch_fsdax()
+# It goes 3 ways based on mount options::
+#      1. "dax" or "dax=always" means always test using DAX
+#      2. "dax=never" means we'll never use DAX
+#      3. "dax=inode" or nothing means "use scratch dev capability" to
+#          determine whether DAX is going to be used.
+#
+# Returns 0 if DAX will be used, 1 if DAX is not going to be used.
+__scratch_uses_fsdax()
 {
-       _normalize_mount_options | egrep -q "dax(=always| |$)" && return 0
+       local ops=$(_normalize_mount_options)
+
+       echo $ops | egrep -qw "dax(=always| |$)" && return 0
+       echo $ops | grep -qw "dax=never" && return 1
 
        local sysfs="/sys/block/$(_short_dev $SCRATCH_DEV)"
        test -e "${sysfs}/dax" && return 0
@@ -1982,6 +1989,8 @@ __detect_scratch_fsdax()
 _require_dm_target()
 {
        local target=$1
+       local fsdax
+       local bdevdax
 
        # require SCRATCH_DEV to be a valid block device with sane BLKFLSBUF
        # behaviour
@@ -1989,7 +1998,7 @@ _require_dm_target()
        _require_sane_bdev_flush $SCRATCH_DEV
        _require_command "$DMSETUP_PROG" dmsetup
 
-       if __detect_scratch_fsdax; then
+       if __scratch_uses_fsdax; then
                case $target in
                stripe|linear|log-writes)
                        ;;