1 files changed, 21 insertions, 19 deletions

diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index 51f940e76c5e..278ed0869c3c 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -491,14 +491,12 @@ static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap,
 {
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_sbd *sdp = GFS2_SB(inode);
-	struct super_block *sb = sdp->sd_vfs;
 	struct buffer_head *dibh = mp->mp_bh[0];
 	u64 bn;
 	unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0;
 	unsigned dblks = 0;
 	unsigned ptrs_per_blk;
 	const unsigned end_of_metadata = mp->mp_fheight - 1;
-	int ret;
 	enum alloc_state state;
 	__be64 *ptr;
 	__be64 zero_bn = 0;
@@ -607,15 +605,6 @@ static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap,
 			iomap->flags |= IOMAP_F_NEW;
 			while (n-- > 0)
 				*ptr++ = cpu_to_be64(bn++);
-			if (flags & IOMAP_ZERO) {
-				ret = sb_issue_zeroout(sb, iomap->addr >> inode->i_blkbits,
-						       dblks, GFP_NOFS);
-				if (ret) {
-					fs_err(sdp,
-					       "Failed to zero data buffers\n");
-					flags &= ~IOMAP_ZERO;
-				}
-			}
 			break;
 		}
 	} while (iomap->addr == IOMAP_NULL_ADDR);
@@ -812,15 +801,22 @@ do_alloc:
 }
 
 /**
- * gfs2_block_map - Map a block from an inode to a disk block
+ * gfs2_block_map - Map one or more blocks of an inode to a disk block
  * @inode: The inode
  * @lblock: The logical block number
  * @bh_map: The bh to be mapped
  * @create: True if its ok to alloc blocks to satify the request
  *
- * Sets buffer_mapped() if successful, sets buffer_boundary() if a
- * read of metadata will be required before the next block can be
- * mapped. Sets buffer_new() if new blocks were allocated.
+ * The size of the requested mapping is defined in bh_map->b_size.
+ *
+ * Clears buffer_mapped(bh_map) and leaves bh_map->b_size unchanged
+ * when @lblock is not mapped.  Sets buffer_mapped(bh_map) and
+ * bh_map->b_size to indicate the size of the mapping when @lblock and
+ * successive blocks are mapped, up to the requested size.
+ *
+ * Sets buffer_boundary() if a read of metadata will be required
+ * before the next block can be mapped. Sets buffer_new() if new
+ * blocks were allocated.
  *
  * Returns: errno
  */
@@ -839,8 +835,6 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
 
 	if (create)
 		flags |= IOMAP_WRITE;
-	if (buffer_zeronew(bh_map))
-		flags |= IOMAP_ZERO;
 	ret = gfs2_iomap_begin(inode, (loff_t)lblock << inode->i_blkbits,
 			       bh_map->b_size, flags, &iomap);
 	if (ret) {
@@ -1344,6 +1338,7 @@ static inline bool walk_done(struct gfs2_sbd *sdp,
 static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length)
 {
 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+	u64 maxsize = sdp->sd_heightsize[ip->i_height];
 	struct metapath mp = {};
 	struct buffer_head *dibh, *bh;
 	struct gfs2_holder rd_gh;
@@ -1359,6 +1354,14 @@ static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length)
 	u64 prev_bnr = 0;
 	__be64 *start, *end;
 
+	if (offset >= maxsize) {
+		/*
+		 * The starting point lies beyond the allocated meta-data;
+		 * there are no blocks do deallocate.
+		 */
+		return 0;
+	}
+
 	/*
 	 * The start position of the hole is defined by lblock, start_list, and
 	 * start_aligned.  The end position of the hole is defined by lend,
@@ -1372,7 +1375,6 @@ static int punch_hole(struct gfs2_inode *ip, u64 offset, u64 length)
 	 */
 
 	if (length) {
-		u64 maxsize = sdp->sd_heightsize[ip->i_height];
 		u64 end_offset = offset + length;
 		u64 lend;
 
@@ -1742,7 +1744,7 @@ do_grow_qunlock:
  * @newsize: the size to make the file
  *
  * The file size can grow, shrink, or stay the same size. This
- * is called holding i_mutex and an exclusive glock on the inode
+ * is called holding i_rwsem and an exclusive glock on the inode
  * in question.
  *
  * Returns: errno