fstests: Use _require_scratch_dax_mountopt() and _require_dax_iflag()

1) Make related tests use _require_scratch_dax_mountopt() and _require_dax_iflag().
2) Remove unused _require_scratch_dax().

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
diff --git a/common/rc b/common/rc
index fa70453..359d03a 100644
--- a/common/rc
+++ b/common/rc
@@ -3174,20 +3174,6 @@
 	_scratch_unmount
 }
 
-# Does dax mount option work on this dev/fs?
-_require_scratch_dax()
-{
-	_require_scratch
-	_scratch_mkfs > /dev/null 2>&1
-	_try_scratch_mount -o dax || \
-		_notrun "mount $SCRATCH_DEV with dax failed"
-	# Check options to be sure. XFS ignores dax option
-	# and goes on if dev underneath does not support dax.
-	_fs_options $SCRATCH_DEV | grep -qw "dax" || \
-		_notrun "$SCRATCH_DEV $FSTYP does not support -o dax"
-	_scratch_unmount
-}
-
 # Check if dax mount options are supported
 #
 # $1 can be either 'dax=always' or 'dax'
diff --git a/tests/ext4/030 b/tests/ext4/030
index 93bbca8..fb5cf45 100755
--- a/tests/ext4/030
+++ b/tests/ext4/030
@@ -33,7 +33,7 @@
 # Modify as appropriate.
 _supported_os Linux
 _supported_fs ext4
-_require_scratch_dax
+_require_scratch_dax_mountopt "dax"
 _require_test_program "t_ext4_dax_journal_corruption"
 _require_command "$CHATTR_PROG" chattr
 
diff --git a/tests/ext4/031 b/tests/ext4/031
index dc58214..20e2fab 100755
--- a/tests/ext4/031
+++ b/tests/ext4/031
@@ -37,7 +37,7 @@
 # Modify as appropriate.
 _supported_os Linux
 _supported_fs ext4
-_require_scratch_dax
+_require_scratch_dax_mountopt "dax"
 _require_test_program "t_ext4_dax_inline_corruption"
 _require_scratch_ext4_feature "inline_data"
 
@@ -56,7 +56,7 @@
 _try_scratch_mount "-o dax" >> $seqres.full 2>&1
 
 if [[ $? != 0 ]]; then
-	# _require_scratch_dax already verified that we could mount with DAX.
+	# _require_scratch_dax_mountopt already verified that we could mount with DAX.
 	# Failure here is expected because we have inline data.
 	echo "Silence is golden"
 	status=0
diff --git a/tests/generic/413 b/tests/generic/413
index 1ce89af..19e1b92 100755
--- a/tests/generic/413
+++ b/tests/generic/413
@@ -31,7 +31,7 @@
 _supported_fs generic
 _supported_os Linux
 _require_test
-_require_scratch_dax
+_require_scratch_dax_mountopt "dax"
 _require_test_program "feature"
 _require_test_program "t_mmap_dio"
 _require_xfs_io_command "falloc"
diff --git a/tests/generic/462 b/tests/generic/462
index 1ab6cad..4a94023 100755
--- a/tests/generic/462
+++ b/tests/generic/462
@@ -37,7 +37,7 @@
 _supported_fs generic
 _supported_os Linux
 _require_test
-_require_scratch_dax
+_require_scratch_dax_mountopt "dax"
 _require_test_program "t_mmap_write_ro"
 # running by unpriviliged user is not necessary to reproduce
 # this bug, just trying to test more.
diff --git a/tests/xfs/260 b/tests/xfs/260
index 3464ffe..bcdc604 100755
--- a/tests/xfs/260
+++ b/tests/xfs/260
@@ -30,10 +30,10 @@
 
 _supported_fs xfs
 _supported_os Linux
-_require_scratch_dax
+_require_scratch_dax_mountopt "dax"
 _require_test_program "feature"
 _require_test_program "t_mmap_dio"
-_require_xfs_io_command "chattr" "x"
+_require_dax_iflag
 _require_xfs_io_command "falloc"
 
 prep_files()