slob: sparsemem support

Currently slob is disabled if we're using sparsemem, due to an earlier
patch from Goto-san.  Slob and static sparsemem work without any trouble as
it is, and the only hiccup is a missing slab_is_available() in the case of
sparsemem extreme.  With this, we're rid of the last set of restrictions
for slob usage.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Matt Mackall <mpm@selenic.com>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slob.c b/mm/slob.c
index b99b0ef..b489907 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -634,6 +634,14 @@
 	return 0;
 }
 
+static unsigned int slob_ready __read_mostly;
+
+int slab_is_available(void)
+{
+	return slob_ready;
+}
+
 void __init kmem_cache_init(void)
 {
+	slob_ready = 1;
 }