diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index fe0500c0af7a..c62d4b9f51dc 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -1327,6 +1327,121 @@ int gfs2_file_dealloc(struct gfs2_inode *ip)
 	return trunc_dealloc(ip, 0);
 }
 
+/**
+ * gfs2_free_journal_extents - Free cached journal bmap info
+ * @jd: The journal
+ *
+ */
+
+void gfs2_free_journal_extents(struct gfs2_jdesc *jd)
+{
+	struct gfs2_journal_extent *jext;
+
+	while(!list_empty(&jd->extent_list)) {
+		jext = list_entry(jd->extent_list.next, struct gfs2_journal_extent, list);
+		list_del(&jext->list);
+		kfree(jext);
+	}
+}
+
+/**
+ * gfs2_add_jextent - Add or merge a new extent to extent cache
+ * @jd: The journal descriptor
+ * @lblock: The logical block at start of new extent
+ * @pblock: The physical block at start of new extent
+ * @blocks: Size of extent in fs blocks
+ *
+ * Returns: 0 on success or -ENOMEM
+ */
+
+static int gfs2_add_jextent(struct gfs2_jdesc *jd, u64 lblock, u64 dblock, u64 blocks)
+{
+	struct gfs2_journal_extent *jext;
+
+	if (!list_empty(&jd->extent_list)) {
+		jext = list_entry(jd->extent_list.prev, struct gfs2_journal_extent, list);
+		if ((jext->dblock + jext->blocks) == dblock) {
+			jext->blocks += blocks;
+			return 0;
+		}
+	}
+
+	jext = kzalloc(sizeof(struct gfs2_journal_extent), GFP_NOFS);
+	if (jext == NULL)
+		return -ENOMEM;
+	jext->dblock = dblock;
+	jext->lblock = lblock;
+	jext->blocks = blocks;
+	list_add_tail(&jext->list, &jd->extent_list);
+	jd->nr_extents++;
+	return 0;
+}
+
+/**
+ * gfs2_map_journal_extents - Cache journal bmap info
+ * @sdp: The super block
+ * @jd: The journal to map
+ *
+ * Create a reusable "extent" mapping from all logical
+ * blocks to all physical blocks for the given journal.  This will save
+ * us time when writing journal blocks.  Most journals will have only one
+ * extent that maps all their logical blocks.  That's because gfs2.mkfs
+ * arranges the journal blocks sequentially to maximize performance.
+ * So the extent would map the first block for the entire file length.
+ * However, gfs2_jadd can happen while file activity is happening, so
+ * those journals may not be sequential.  Less likely is the case where
+ * the users created their own journals by mounting the metafs and
+ * laying it out.  But it's still possible.  These journals might have
+ * several extents.
+ *
+ * Returns: 0 on success, or error on failure
+ */
+
+int gfs2_map_journal_extents(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
+{
+	u64 lblock = 0;
+	u64 lblock_stop;
+	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
+	struct buffer_head bh;
+	unsigned int shift = sdp->sd_sb.sb_bsize_shift;
+	u64 size;
+	int rc;
+
+	lblock_stop = i_size_read(jd->jd_inode) >> shift;
+	size = (lblock_stop - lblock) << shift;
+	jd->nr_extents = 0;
+	WARN_ON(!list_empty(&jd->extent_list));
+
+	do {
+		bh.b_state = 0;
+		bh.b_blocknr = 0;
+		bh.b_size = size;
+		rc = gfs2_block_map(jd->jd_inode, lblock, &bh, 0);
+		if (rc || !buffer_mapped(&bh))
+			goto fail;
+		rc = gfs2_add_jextent(jd, lblock, bh.b_blocknr, bh.b_size >> shift);
+		if (rc)
+			goto fail;
+		size -= bh.b_size;
+		lblock += (bh.b_size >> ip->i_inode.i_blkbits);
+	} while(size > 0);
+
+	fs_info(sdp, "journal %d mapped with %u extents\n", jd->jd_jid,
+		jd->nr_extents);
+	return 0;
+
+fail:
+	fs_warn(sdp, "error %d mapping journal %u at offset %llu (extent %u)\n",
+		rc, jd->jd_jid,
+		(unsigned long long)(i_size_read(jd->jd_inode) - size),
+		jd->nr_extents);
+	fs_warn(sdp, "bmap=%d lblock=%llu block=%llu, state=0x%08lx, size=%llu\n",
+		rc, (unsigned long long)lblock, (unsigned long long)bh.b_blocknr,
+		bh.b_state, (unsigned long long)bh.b_size);
+	gfs2_free_journal_extents(jd);
+	return rc;
+}
+
 /**
  * gfs2_write_alloc_required - figure out if a write will require an allocation
  * @ip: the file being written to
diff --git a/fs/gfs2/bmap.h b/fs/gfs2/bmap.h
index 42fea03e2bd9..81ded5e2aaa2 100644
--- a/fs/gfs2/bmap.h
+++ b/fs/gfs2/bmap.h
@@ -55,5 +55,7 @@ extern int gfs2_truncatei_resume(struct gfs2_inode *ip);
 extern int gfs2_file_dealloc(struct gfs2_inode *ip);
 extern int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
 				     unsigned int len);
+extern int gfs2_map_journal_extents(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd);
+extern void gfs2_free_journal_extents(struct gfs2_jdesc *jd);
 
 #endif /* __BMAP_DOT_H__ */
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index d0c3928b2dea..456d8fa9da2b 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -485,7 +485,7 @@ struct gfs2_trans {
 };
 
 struct gfs2_journal_extent {
-	struct list_head extent_list;
+	struct list_head list;
 
 	unsigned int lblock; /* First logical block */
 	u64 dblock; /* First disk block */
@@ -495,6 +495,7 @@ struct gfs2_journal_extent {
 struct gfs2_jdesc {
 	struct list_head jd_list;
 	struct list_head extent_list;
+	unsigned int nr_extents;
 	struct work_struct jd_work;
 	struct inode *jd_inode;
 	unsigned long jd_flags;
diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 23c6e72f5164..ae1d6352a1eb 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -146,8 +146,8 @@ static u64 gfs2_log_bmap(struct gfs2_sbd *sdp)
 	struct gfs2_journal_extent *je;
 	u64 block;
 
-	list_for_each_entry(je, &sdp->sd_jdesc->extent_list, extent_list) {
-		if (lbn >= je->lblock && lbn < je->lblock + je->blocks) {
+	list_for_each_entry(je, &sdp->sd_jdesc->extent_list, list) {
+		if ((lbn >= je->lblock) && (lbn < (je->lblock + je->blocks))) {
 			block = je->dblock + lbn - je->lblock;
 			gfs2_log_incr_head(sdp);
 			return block;
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 1f855a74a4ec..e0d0db5f7fc6 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -517,67 +517,6 @@ out:
 	return ret;
 }
 
-/**
- * map_journal_extents - create a reusable "extent" mapping from all logical
- * blocks to all physical blocks for the given journal.  This will save
- * us time when writing journal blocks.  Most journals will have only one
- * extent that maps all their logical blocks.  That's because gfs2.mkfs
- * arranges the journal blocks sequentially to maximize performance.
- * So the extent would map the first block for the entire file length.
- * However, gfs2_jadd can happen while file activity is happening, so
- * those journals may not be sequential.  Less likely is the case where
- * the users created their own journals by mounting the metafs and
- * laying it out.  But it's still possible.  These journals might have
- * several extents.
- *
- * TODO: This should be done in bigger chunks rather than one block at a time,
- *       but since it's only done at mount time, I'm not worried about the
- *       time it takes.
- */
-static int map_journal_extents(struct gfs2_sbd *sdp)
-{
-	struct gfs2_jdesc *jd = sdp->sd_jdesc;
-	unsigned int lb;
-	u64 db, prev_db; /* logical block, disk block, prev disk block */
-	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
-	struct gfs2_journal_extent *jext = NULL;
-	struct buffer_head bh;
-	int rc = 0;
-
-	prev_db = 0;
-
-	for (lb = 0; lb < i_size_read(jd->jd_inode) >> sdp->sd_sb.sb_bsize_shift; lb++) {
-		bh.b_state = 0;
-		bh.b_blocknr = 0;
-		bh.b_size = 1 << ip->i_inode.i_blkbits;
-		rc = gfs2_block_map(jd->jd_inode, lb, &bh, 0);
-		db = bh.b_blocknr;
-		if (rc || !db) {
-			printk(KERN_INFO "GFS2 journal mapping error %d: lb="
-			       "%u db=%llu\n", rc, lb, (unsigned long long)db);
-			break;
-		}
-		if (!prev_db || db != prev_db + 1) {
-			jext = kzalloc(sizeof(struct gfs2_journal_extent),
-				       GFP_KERNEL);
-			if (!jext) {
-				printk(KERN_INFO "GFS2 error: out of memory "
-				       "mapping journal extents.\n");
-				rc = -ENOMEM;
-				break;
-			}
-			jext->dblock = db;
-			jext->lblock = lb;
-			jext->blocks = 1;
-			list_add_tail(&jext->extent_list, &jd->extent_list);
-		} else {
-			jext->blocks++;
-		}
-		prev_db = db;
-	}
-	return rc;
-}
-
 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
 {
 	char *message = "FIRSTMOUNT=Done";
@@ -779,7 +718,7 @@ static int init_journal(struct gfs2_sbd *sdp, int undo)
 		atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 
 		/* Map the extents for this journal's blocks */
-		map_journal_extents(sdp);
+		gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
 	}
 	trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
 
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 60f60f6181f3..25747440ebbb 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -295,9 +295,8 @@ int gfs2_mount_args(struct gfs2_args *args, char *options)
 
 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 {
-	struct list_head list, *head;
+	struct list_head list;
 	struct gfs2_jdesc *jd;
-	struct gfs2_journal_extent *jext;
 
 	spin_lock(&sdp->sd_jindex_spin);
 	list_add(&list, &sdp->sd_jindex_list);
@@ -307,14 +306,7 @@ void gfs2_jindex_free(struct gfs2_sbd *sdp)
 
 	while (!list_empty(&list)) {
 		jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
-		head = &jd->extent_list;
-		while (!list_empty(head)) {
-			jext = list_entry(head->next,
-					  struct gfs2_journal_extent,
-					  extent_list);
-			list_del(&jext->extent_list);
-			kfree(jext);
-		}
+		gfs2_free_journal_extents(jd);
 		list_del(&jd->jd_list);
 		iput(jd->jd_inode);
 		kfree(jd);