[RFC PATCH v2 4/7] User get_mount_info to replace findmnt calls

[Kairui Song]

Use get_mount_info so that fstab is used as a failback when look for
mount info.

Signed-off-by: Kairui Song <kasong(a)redhat.com&gt;
---
 kdump-lib-initramfs.sh | 23 ++++++++++-------------
 kdump-lib.sh           |  1 -
 kdumpctl               |  4 ++--
 mkdumprd               | 42 +++++++++++++++---------------------------
 4 files changed, 27 insertions(+), 43 deletions(-)

diff --git a/kdump-lib-initramfs.sh b/kdump-lib-initramfs.sh
index c374c4b..ab78be3 100755
--- a/kdump-lib-initramfs.sh
+++ b/kdump-lib-initramfs.sh
@@ -94,19 +94,16 @@ get_kdump_confs()
     fi
 }
 
-# dump_fs <mount point| device>
+# dump_fs <mount point>
 dump_fs()
 {
-    local _dev=$(findmnt -k -f -n -r -o SOURCE $1)
-    local _mp=$(findmnt -k -f -n -r -o TARGET $1)
-    local _op=$(findmnt -k -f -n -r -o OPTIONS $1)
+    local _mp=$1
+    local _dev=$(get_mount_info SOURCE target $_mp -f)
+    local _op=$(get_mount_info OPTIONS target $_mp -f)
 
-    if ! is_mounted "$_mp"; then
-        _dev=$(findmnt -s -f -n -r -o SOURCE $1)
-        _mp=$(findmnt -s -f -n -r -o TARGET $1)
-        _op=$(findmnt -s -f -n -r -o OPTIONS $1)
-
-        if [ -n "$_dev" ] && [ -n "$_mp" ]; then
+    # If dump path have a corresponding device entry but not mounted, mount it.
+    if [ -n "$_dev" ]; then
+        if ! is_mounted "$_mp"; then
             echo "kdump: dump target $_dev is not mounted, trying to mount..."
             mkdir -p $_mp
             mount -o $_op $_dev $_mp
@@ -115,11 +112,10 @@ dump_fs()
                 echo "kdump: mounting failed (mount point: $_mp, option:
$_op)"
                 return 1
             fi
-        else
-            echo "kdump: error: Dump target $_dev is not usable"
         fi
     else
-        echo "kdump: dump target is $_dev"
+        echo "kdump: failed to dump to \"$_mp\", it's not a mount
point!"
+        return 1
     fi
 
     # Remove -F in makedumpfile case. We don't want a flat format dump here.
@@ -260,6 +256,7 @@ read_kdump_conf()
             [ -n "$config_val" ] && add_dump_code "dump_fs
$config_val"
             ;;
         ext[234]|xfs|btrfs|minix|nfs)
+            config_val=$(get_mntpoint_from_target "$config_val")
             add_dump_code "dump_fs $config_val"
             ;;
         raw)
diff --git a/kdump-lib.sh b/kdump-lib.sh
index 95162cd..691a14d 100755
--- a/kdump-lib.sh
+++ b/kdump-lib.sh
@@ -270,7 +270,6 @@ get_mntopt_from_target()
 {
     get_mount_info OPTIONS source $1 -f
 }
-
 # Find the general mount point of a dump target, not the bind mount point
 get_mntpoint_from_target()
 {
diff --git a/kdumpctl b/kdumpctl
index 23c0c38..4a674f2 100755
--- a/kdumpctl
+++ b/kdumpctl
@@ -907,8 +907,8 @@ path_to_be_relabeled()
 
 		_target=$(local_fs_dump_target)
 		if [[ -n "$_target" ]]; then
-			_mnt=$(findmnt -k -f -n -r -o TARGET $_target)
-			if [ -z "$_mnt" ]; then
+			_mnt=$(get_mntpoint_from_target $_target)
+			if ! is_mounted "$_mnt"; then
 				return
 			fi
 		else
diff --git a/mkdumprd b/mkdumprd
index 4fc0a5b..d08a34d 100644
--- a/mkdumprd
+++ b/mkdumprd
@@ -51,21 +51,18 @@ add_dracut_sshkey() {
 
 # caller should ensure $1 is valid and mounted in 1st kernel
 to_mount() {
-    local _dev=$1 _source _new_mntpoint _fstype _options _mntopts _pdev
-
-    _source=$(findmnt -k -f -n -r -o SOURCE $_dev)
-    _fstype=$(findmnt -k -f -n -r -o FSTYPE $_dev)
-    _new_mntpoint=$(get_kdump_mntpoint_from_target $_dev)
-
-    [[ -e /etc/fstab ]] && _options=$(findmnt --fstab -f -n -r -o OPTIONS $_dev)
-    if [ -z "$_options" ]; then
-        _options=$(findmnt -k -f -n -r -o OPTIONS $_dev)
-        if [[ $_fstype == "nfs"* ]]; then
-            _options=$(echo $_options | sed 's/,addr=[^,]*//')
-            _options=$(echo $_options | sed 's/,proto=[^,]*//')
-            _options=$(echo $_options | sed 's/,clientaddr=[^,]*//')
-        fi
+    local _target=$1 _new_mntpoint _fstype _options _mntopts _pdev
+
+    _fstype=$(get_fs_type_from_target $_target)
+    _options=$(get_mntopt_from_target $_target)
+    _new_mntpoint=$(get_kdump_mntpoint_from_target $_target)
+
+    if [[ "$_fstype" == "nfs"* ]]; then
+        _options=$(echo $_options | sed 's/,addr=[^,]*//')
+        _options=$(echo $_options | sed 's/,proto=[^,]*//')
+        _options=$(echo $_options | sed 's/,clientaddr=[^,]*//')
     fi
+
     # mount fs target as rw in 2nd kernel
     _options=$(echo $_options | sed 's/\(^\|,\)ro\($\|,\)/\1rw\2/g')
     # with 'noauto' in fstab nfs and non-root disk mount will fail in 2nd
@@ -79,28 +76,19 @@ to_mount() {
     _options="$_options,nofail,x-systemd.before=kdump-capture.service"
 
     _mntopts="$_new_mntpoint $_fstype $_options"
-    # for non-nfs _dev converting to use udev persistent name
-    if [ -b "$_source" ]; then
-        _pdev="$(get_persistent_dev $_source)"
+    # for non-nfs _target converting to use udev persistent name
+    if [ -b "$_target" ]; then
+        _pdev="$(get_persistent_dev $_target)"
         if [ -z "$_pdev" ]; then
             return 1
         fi
     else
-        _pdev=$_dev
+        _pdev=$_target
     fi
 
     echo "$_pdev $_mntopts"
 }
 
-is_readonly_mount() {
-    local _mnt
-    _mnt=$(findmnt -k -f -n -r -o OPTIONS $1)
-
-    #fs/proc_namespace.c: show_mountinfo():
-    #seq_puts(m, mnt->mnt_flags & MNT_READONLY ? " ro" : "
rw");
-    [[ "$_mnt" =~ ^ro ]]
-}
-
 #Function: get_ssh_size
 #$1=dump target
 #called from while loop and shouldn't read from stdin, so we're using "ssh
-n"
-- 
2.26.2