Adding upstream version 4.2.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tests/04update-metadata

@@ -0,0 +1,48 @@
+set -xe
+
+# test converting v0.90 to v1.0
+# check for different levels
+# check it fails for non-v0.90
+# check it fails during reshape or recovery
+# check it fails when bitmap is present
+
+dlist="$dev0 $dev1 $dev2 $dev3"
+
+for ls in raid0/4 linear/4 raid1/1 raid5/3 raid6/2
+do
+  s=${ls#*/} l=${ls%/*}
+  mdadm -CR --assume-clean -e 0.90 $md0 --level $l -n 4 -c 64 $dlist
+  testdev $md0 $s 19904 64
+  mdadm -S $md0
+  mdadm -A $md0 --update=metadata $dlist
+  testdev $md0 $s 19904 64 check
+  mdadm -S $md0
+done
+
+if mdadm -A $md0 --update=metadata $dlist
+then echo >&2 should fail with v1.0 metadata
+     exit 1
+fi
+
+mdadm -CR -e 0.90 $md0 --level=6 -n4 -c32 $dlist
+mdadm -S $md0
+
+if mdadm -A $md0 --update=metadata $dlist
+then echo >&2 should fail during resync
+     exit 1
+fi
+mdadm -A $md0 $dlist
+mdadm --wait $md0 || true
+mdadm -S $md0
+
+# should succeed now
+mdadm -A $md0 --update=metadata $dlist
+
+mdadm -S /dev/md0
+mdadm -CR --assume-clean -e 0.90 $md0 --level=6 -n4 -c32 $dlist --bitmap=internal
+mdadm -S $md0
+
+if mdadm -A $md0 --update=metadata $dlist
+then echo >&2 should fail when bitmap present
+     exit 1
+fi