[PATCH] allow kickstart to preexisting LV w/ encrypted PV (448129)

[Dave Lehman <dlehman redhat com>]

The referenced bug is a failure to kickstart when the user specifies
that we install to a pre-existing logical volume which contains one or
more encrypted physical volumes.

Joel's recent patch to Partitions.setFromDisk gets us part of the way
there by prompting for a passphrase so we can look at the pv.

The second problem comes when lvm, in all it's brilliance, returns
'/dev/dm-0' from pvdisplay instead of '/dev/mapper/foo'. I have a little
patch to resolve /dev/dm-X to a useful (ie: persistent) device mapper
name.

Comments, suggestions?

I'm also curious whether people think we should stuff this into F10. I
think we should, assuming we will be building for it again anyhow.

diff --git a/lvm.py b/lvm.py
index d1de501..00f7c02 100644
--- a/lvm.py
+++ b/lvm.py
@@ -373,6 +373,19 @@ def pvlist():
             size = long(math.floor(long(size) / (1024 * 1024)))
         except:
             continue
+
+        if dev.startswith("/dev/dm-"):
+            from block import dm
+            try:
+                sb = os.stat(dev)
+                (major, minor) = (os.major(sb.st_rdev),
os.minor(sb.st_rdev))
+                for map in dm.maps():
+                    if map.dev.major == major and map.dev.minor ==
minor:
+                        dev = "/dev/mapper/%s" % map.name
+                        break
+            except:
+                pass
+
         log.info("pv is %s in vg %s, size is %s" %(dev, vg, size))
         pvs.append( (dev, vg, size) )
 

Dave