mm, mempool: do not allow atomic resizing

Allocating a large number of elements in atomic context could quickly
deplete memory reserves, so just disallow atomic resizing entirely.

Nothing currently uses mempool_resize() with anything other than
GFP_KERNEL, so convert existing callers to drop the gfp_mask.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Steffen Maier <maier@linux.vnet.ibm.com>	[zfcp]
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mempool.h b/include/linux/mempool.h
index 39ed62a..b19b302 100644
--- a/include/linux/mempool.h
+++ b/include/linux/mempool.h
@@ -29,7 +29,7 @@
 			mempool_free_t *free_fn, void *pool_data,
 			gfp_t gfp_mask, int nid);
 
-extern int mempool_resize(mempool_t *pool, int new_min_nr, gfp_t gfp_mask);
+extern int mempool_resize(mempool_t *pool, int new_min_nr);
 extern void mempool_destroy(mempool_t *pool);
 extern void * mempool_alloc(mempool_t *pool, gfp_t gfp_mask);
 extern void mempool_free(void *element, mempool_t *pool);