Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  [GFS2] fix gfs2 block allocation (cleaned up)
  [GFS2] BUG: unable to handle kernel paging request at ffff81002690e000

fs/gfs2/bmap.c

@@ -246,15 +246,11 @@ static void find_metapath(const struct gfs2_sbd *sdp, u64 block,
 
 }
 
-static inline unsigned int zero_metapath_length(const struct metapath *mp,
-						unsigned height)
+static inline unsigned int metapath_branch_start(const struct metapath *mp)
 {
-	unsigned int i;
-	for (i = 0; i < height - 1; i++) {
-		if (mp->mp_list[i] != 0)
-			return i;
-	}
-	return height;
+	if (mp->mp_list[0] == 0)
+		return 2;
+	return 1;
 }
 
 /**
@@ -436,7 +432,7 @@ static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock,
 	struct gfs2_sbd *sdp = GFS2_SB(inode);
 	struct buffer_head *dibh = mp->mp_bh[0];
 	u64 bn, dblock = 0;
-	unsigned n, i, blks, alloced = 0, iblks = 0, zmpl = 0;
+	unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0;
 	unsigned dblks = 0;
 	unsigned ptrs_per_blk;
 	const unsigned end_of_metadata = height - 1;
@@ -471,9 +467,8 @@ static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock,
 			/* Building up tree height */
 			state = ALLOC_GROW_HEIGHT;
 			iblks = height - ip->i_height;
-			zmpl = zero_metapath_length(mp, height);
-			iblks -= zmpl;
-			iblks += height;
+			branch_start = metapath_branch_start(mp);
+			iblks += (height - branch_start);
 		}
 	}
 
@@ -509,13 +504,13 @@ static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock,
 					sizeof(struct gfs2_meta_header));
 				*ptr = zero_bn;
 				state = ALLOC_GROW_DEPTH;
-				for(i = zmpl; i < height; i++) {
+				for(i = branch_start; i < height; i++) {
 					if (mp->mp_bh[i] == NULL)
 						break;
 					brelse(mp->mp_bh[i]);
 					mp->mp_bh[i] = NULL;
 				}
-				i = zmpl;
+				i = branch_start;
 			}
 			if (n == 0)
 				break;

fs/gfs2/rgrp.c

@@ -195,7 +195,7 @@ static u32 gfs2_bitfit(const u8 *buffer, unsigned int buflen, u32 goal,
 	   depending on architecture.  I've experimented with several ways
 	   of writing this section such as using an else before the goto
 	   but this one seems to be the fastest. */
-	while ((unsigned char *)plong < end - 1) {
+	while ((unsigned char *)plong < end - sizeof(unsigned long)) {
 		prefetch(plong + 1);
 		if (((*plong) & LBITMASK) != lskipval)
 			break;