JBD2: jbd2 slab allocation cleanups

JBD2: Replace slab allocations with page allocations

JBD2 allocate memory for committed_data and frozen_data from slab. However
JBD2 should not pass slab pages down to the block layer. Use page allocator
pages instead. This will also prepare JBD for the large blocksize patchset.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index c0f59d1..2cac34a 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -384,7 +384,7 @@
 			struct buffer_head *bh = jh2bh(jh);
 
 			jbd_lock_bh_state(bh);
-			jbd2_slab_free(jh->b_committed_data, bh->b_size);
+			jbd2_free(jh->b_committed_data, bh->b_size);
 			jh->b_committed_data = NULL;
 			jbd_unlock_bh_state(bh);
 		}
@@ -801,14 +801,14 @@
 		 * Otherwise, we can just throw away the frozen data now.
 		 */
 		if (jh->b_committed_data) {
-			jbd2_slab_free(jh->b_committed_data, bh->b_size);
+			jbd2_free(jh->b_committed_data, bh->b_size);
 			jh->b_committed_data = NULL;
 			if (jh->b_frozen_data) {
 				jh->b_committed_data = jh->b_frozen_data;
 				jh->b_frozen_data = NULL;
 			}
 		} else if (jh->b_frozen_data) {
-			jbd2_slab_free(jh->b_frozen_data, bh->b_size);
+			jbd2_free(jh->b_frozen_data, bh->b_size);
 			jh->b_frozen_data = NULL;
 		}