Fix various issues with dmraid handling (#485895, <hdegoede@redhat.com>)

I've been doing a lot of work on mkinitrd's dmraid support lately some of the
lessons learned there also apply to the activation of (not used for /) dmraid
arrays in rc.sysinit, this will esp. help the livecd proerly activating and
using dmraid sets.

The patch fixes the following issues:

1) rc.sysinit (and mkinitrd used to) calls dm_resolve_name() on the output of
dmraid, this is not necessary as dm_resolve_name is only needed when the name
is /dev/dm-#, it is actually harmful as dm_resolve_name sometimes fails when
used like this, causing us to fail to activate dmraid sets

2) rc.sysinit does not remove the partitions from the raw disks used in a
raidset the initrd used to use special nash functionality to tell the kernels
to forget about the partitions of the raw disks it had scanned at boot. The
issue here is, say we have a mirror of sda and sdb, and that mirror has 2
partitions. Then the kernel when scanning the raw disks will find
sda1,sda2,sdb1,sdb2. But we do not want anything using those, they should use
the devicemapper versions as those are mirrored! I've even seen mounting by
LABEL / UUID do the wrong thing by using the raw partitions instead of the
raidset partitions.

I've recently done a patch to dmraid adding a --rm_partitions cmdline option
which makes dmraid do the ioctl which makes the kernel forget about the
partitions of the rawdisk (which in turn makes udev remove the device nodes).
This way we no longer need the nash magic.

Part of my rc.sysinit patch is adding --rm_partitions to the dmraid invocation

3) rc.sysinit uses dmraid -p, which tells dmraid to not setup device maps for
the partitions of the raidset and then kalls kpartx to setup the device maps
for the partitions. This can be simplified by removing the -p argument to
dmraid

4) with all these changes in place there is no longer a reason to loop, a
single dmraid invocation is enough.

p.s.

AFAIK with this patch the last user of dm_resolve_name is gone, so that
function can be removed. Better check twice though.

1 files changed, 1 insertions, 8 deletions

diff --git a/rc.d/rc.sysinit b/rc.d/rc.sysinit
index 832bcc2a..17b4de6f 100755
--- a/rc.d/rc.sysinit
+++ b/rc.d/rc.sysinit
@@ -358,14 +358,7 @@ fi
 	
 	if ! strstr "$cmdline" nodmraid && [ -x /sbin/dmraid ]; then
 		modprobe dm-mirror >/dev/null 2>&1
-		for x in $(/sbin/dmraid -ay -i -p -t 2>/dev/null | \
-				egrep -iv "^no " | \
-				(IFS=":";while read a rest;do echo $a;done)) ; do
-			dmname=$(resolve_dm_name $x)
-			[ -z "$dmname" ] && continue
-			/sbin/dmraid -ay -i -p "$dmname" >/dev/null 2>&1
-			/sbin/kpartx -a -p p "/dev/mapper/$dmname"
-		done
+		/sbin/dmraid -ay -i --rm_partitions >/dev/null 2>&1
 	fi
 	
 	if [ -x /sbin/lvm ]; then