mdcheck: loop over sync_action files in sysfs

The way mdcheck is currently written, it loops over /dev/md?*, which
will contain RAID partitions and arrays that don't support sync
operations, such as RAID0. This is inefficient and makes the script
difficult to trace.

Instead, loop over the sync_action files which actually matter for
checking.

Signed-off-by: Martin Wilck <mwilck@suse.com>

diff --git a/misc/mdcheck b/misc/mdcheck
index 398a1ea607ca44199a59790bacb977af89b89a9f..e654c5c5d7454a26e04dc47992d0290da7931e4a 100644 (file)
--- a/misc/mdcheck
+++ b/misc/mdcheck
@@ -31,12 +31,13 @@
 # To support '--continue', arrays are identified by UUID and the 'sync_completed'
 # value is stored  in /var/lib/mdcheck/$UUID
 
-# convert a /dev/md name into /sys/.../md equivalent
-sysname() {
-       set `ls -lLd $1`
-       maj=${5%,}
-       min=$6
-       readlink -f /sys/dev/block/$maj:$min
+# get device name from sysfs
+devname() {
+    local dev
+    [[ -f "$1/uevent" ]] && \
+           dev=$(. "$1/uevent" && echo -n "$DEVNAME")
+    [[ "$dev" && -b "/dev/$dev" ]] || return 1
+    echo -n "/dev/$dev"
 }
 
 args=$(getopt -o hcd: -l help,continue,duration: -n mdcheck -- "$@")
@@ -100,21 +101,20 @@ mkdir -p /var/lib/mdcheck
 find /var/lib/mdcheck -name "MD_UUID*" -type f -mtime +180 -exec rm {} \;
 
 # Now look at each md device.
-for dev in /dev/md?*
+for sync_act in /sys/block/*/md/sync_action
 do
-       [ -e "$dev" ] || continue
-       sys=`sysname $dev`
-       if [ ! -f "$sys/md/sync_action" ]
-       then # cannot check this array
-               continue
-       fi
-       if [ "`cat $sys/md/sync_action`" != 'idle' ]
+       [ -e "$sync_act" ] || continue
+       if [ "`cat $sync_act`" != 'idle' ]
        then # This array is busy
                continue
        fi
 
+       sys=${sync_act%/md/*}
+       dev=$(devname "$sys") || continue
        mdadm --detail --export "$dev" | grep '^MD_UUID=' > $tmp || continue
        source $tmp
+       [[ "$MD_UUID" ]] || continue
+
        fl="/var/lib/mdcheck/MD_UUID_$MD_UUID"
        if [ -z "$cont" ]
        then