[kexec-tools] use findmnt instead of blkid in mkdumprd

[Baoquan He]

commit 4b9c868b8de57d49aad822f386945c01e8f2ddfe
Author: dyoung at redhat.com <dyoung at redhat.com>
Date:   Tue Mar 5 16:07:35 2013 +0800

    use findmnt instead of blkid in mkdumprd
    
    Previously to_dev_name use blkid to get dev name from dump target,
    but blkid can not handle UUID/LABEL with quotes so to_dev_name will
    silently fail.
    
    Because we enforce dump target being mounted before creating kdump
    initrd, so change to use findmnt is fine. findmnt can handle input
    params with quotes.
    
    to_dev_name is not necessary anymore, just remove it.
    Also there's another user of it is for checking if the dev is root
    or not, here change to use findmnt for this as well.
    
    Tested the rootfs dump, UUID with/without quotes dump.
    
    Signed-off-by: Dave Young <dyoung at redhat.com>
    Reviewed-by: Caspar Zhang <czhang at redhat.com>
    Acked-by: Baoquan He <bhe at redhat.com>

 mkdumprd |   32 ++++++++++----------------------
 1 files changed, 10 insertions(+), 22 deletions(-)
---
diff --git a/mkdumprd b/mkdumprd
index af630c2..719e6f2 100644
--- a/mkdumprd
+++ b/mkdumprd
@@ -59,35 +59,23 @@ add_dracut_sshkey() {
 # Generic substring function.  If $2 is in $1, return 0.
 strstr() { [[ $1 =~ $2 ]]; }
 
-to_dev_name() {
-    local dev="$1"
-
-    case "$dev" in
-    UUID=*)
-        dev=`blkid -U "${dev#UUID=}"`
-        ;;
-    LABEL=*)
-        dev=`blkid -L "${dev#LABEL=}"`
-        ;;
-    esac
-    echo $dev
-}
-
-get_rootdev() {
-    mount | grep 'on / ' | grep -v rootfs | awk '{print $1}'
+target_is_root() {
+    local _t
+    _t=$(findmnt -k -n -r -o TARGET $1|sort|head -1)
+    [ "$_t" = "/" ]
 }
 
 to_mount() {
-    local _dev _t _o _mntopts _pdev
-    _dev=$(to_dev_name $1)
+    local _dev=$1 _s _t _o _mntopts _pdev
+    _s=$(findmnt -k -f -n -r -o SOURCE $_dev)
     _t=$(findmnt -k -f -n -r -o TARGET,FSTYPE $_dev)
     _o=$(findmnt -k -f -n -r -o OPTIONS $_dev)
     [ -z "$_t" -o -z "$_o" ] && return
     _o=${_o/#ro/rw} #mount fs target as rw in 2nd kernel
     _mntopts="$_t $_o"
     #for non-nfs _dev converting to use udev persistent name
-    if [ -b "$_dev" ]; then
-        _pdev="$(get_persistent_dev $_dev)"
+    if [ -b "$_s" ]; then
+        _pdev="$(get_persistent_dev $_s)"
     else
         _pdev=$_dev
     fi
@@ -222,9 +210,9 @@ verify_core_collector() {
 }
 
 add_mount() {
-    local _dev=$(to_dev_name "$1")
     local _mnt=$(to_mount "$1")
-    if [ "$_dev" = "$(get_rootdev)" ]; then
+
+    if target_is_root "$1"; then
         :
     elif [ -n "$_mnt" ]; then
         add_dracut_mount "$_mnt"