Index: sys/fs/ext2fs/ext2_bmap.c
===================================================================
--- sys/fs/ext2fs/ext2_bmap.c	(revision 295446)
+++ sys/fs/ext2fs/ext2_bmap.c	(working copy)
@@ -114,6 +114,8 @@
 		if (runp != NULL)
 			*runp = path.ep_sparse_ext.e_len -
 			    (lbn - path.ep_sparse_ext.e_blk) - 1;
+		if (runb != NULL)
+			*runb = lbn - path.ep_sparse_ext.e_blk;
 	} else {
 		ep = path.ep_ext;
 		if (ep == NULL)
@@ -127,6 +129,8 @@
 
 			if (runp != NULL)
 				*runp = ep->e_len - (lbn - ep->e_blk) - 1;
+			if (runb != NULL)
+				*runb = lbn - ep->e_blk;
 		}
 	}
 
Index: sys/fs/ext2fs/ext2_extents.c
===================================================================
--- sys/fs/ext2fs/ext2_extents.c	(revision 295446)
+++ sys/fs/ext2fs/ext2_extents.c	(working copy)
@@ -43,14 +43,17 @@
 #include <fs/ext2fs/ext2_extents.h>
 #include <fs/ext2fs/ext2_extern.h>
 
-static void ext4_ext_binsearch_index(struct inode *ip, struct ext4_extent_path
-		*path, daddr_t lbn)
+static int
+ext4_ext_binsearch_index(struct inode *ip, struct ext4_extent_path *path,
+		daddr_t lbn, daddr_t *first_lbn, daddr_t *last_lbn)
 {
 	struct ext4_extent_header *ehp = path->ep_header;
-	struct ext4_extent_index *l, *r, *m;
+	struct ext4_extent_index *first, *last, *l, *r, *m;
 
-	l = (struct ext4_extent_index *)(char *)(ehp + 1);
-	r = (struct ext4_extent_index *)(char *)(ehp + 1) + ehp->eh_ecount - 1;
+	first = (struct ext4_extent_index *)(char *)(ehp + 1);
+	last = first + ehp->eh_ecount - 1;
+	l = first;
+	r = last;
 	while (l <= r) {
 		m = l + (r - l) / 2;
 		if (lbn < m->ei_blk)
@@ -59,11 +62,24 @@
 			l = m + 1;
 	}
 
+	if (l == first) {
+		path->ep_sparse_ext.e_blk = *first_lbn;
+		path->ep_sparse_ext.e_len = first->ei_blk - *first_lbn;
+		path->ep_sparse_ext.e_start_hi = 0;
+		path->ep_sparse_ext.e_start_lo = 0;
+		path->ep_is_sparse = 1;
+		return (1);
+	}
 	path->ep_index = l - 1;
+	*first_lbn = path->ep_index->ei_blk;
+	if (path->ep_index < last)
+		*last_lbn = l->ei_blk - 1;
+	return (0);
 }
 
 static void
-ext4_ext_binsearch(struct inode *ip, struct ext4_extent_path *path, daddr_t lbn)
+ext4_ext_binsearch(struct inode *ip, struct ext4_extent_path *path, daddr_t lbn,
+		daddr_t first_lbn, daddr_t last_lbn)
 {
 	struct ext4_extent_header *ehp = path->ep_header;
 	struct ext4_extent *first, *l, *r, *m;
@@ -83,8 +99,8 @@
 	}
 
 	if (l == first) {
-		path->ep_sparse_ext.e_blk = lbn;
-		path->ep_sparse_ext.e_len = first->e_blk - lbn;
+		path->ep_sparse_ext.e_blk = first_lbn;
+		path->ep_sparse_ext.e_len = first->e_blk - first_lbn;
 		path->ep_sparse_ext.e_start_hi = 0;
 		path->ep_sparse_ext.e_start_lo = 0;
 		path->ep_is_sparse = 1;
@@ -92,11 +108,14 @@
 	}
 	path->ep_ext = l - 1;
 	if (path->ep_ext->e_blk + path->ep_ext->e_len <= lbn) {
-		path->ep_sparse_ext.e_blk = lbn;
+		path->ep_sparse_ext.e_blk = path->ep_ext->e_blk +
+		    path->ep_ext->e_len;
 		if (l <= (first + ehp->eh_ecount - 1))
-			path->ep_sparse_ext.e_len = l->e_blk - lbn;
-		else	// XXX: where does it end?
-			path->ep_sparse_ext.e_len = 1;
+			path->ep_sparse_ext.e_len = l->e_blk -
+			    path->ep_sparse_ext.e_blk;
+		else
+			path->ep_sparse_ext.e_len = last_lbn -
+			    path->ep_sparse_ext.e_blk + 1;
 		path->ep_sparse_ext.e_start_hi = 0;
 		path->ep_sparse_ext.e_start_lo = 0;
 		path->ep_is_sparse = 1;
@@ -162,10 +181,16 @@
 
 	path->ep_header = ehp;
 
+	daddr_t first_lbn = 0;
+	daddr_t last_lbn = lblkno(ip->i_e2fs, ip->i_size);
+
 	for (i = ehp->eh_depth; i != 0; --i) {
-		ext4_ext_binsearch_index(ip, path, lbn);
-		path->ep_depth = 0;
+		path->ep_depth = i;
 		path->ep_ext = NULL;
+		if (ext4_ext_binsearch_index(ip, path, lbn, &first_lbn,
+		    &last_lbn)) {
+			return (path);
+		}
 
 		nblk = (daddr_t)path->ep_index->ei_leaf_hi << 32 |
 		    path->ep_index->ei_leaf_lo;
@@ -190,6 +215,6 @@
 	path->ep_index = NULL;
 	path->ep_is_sparse = 0;
 
-	ext4_ext_binsearch(ip, path, lbn);
+	ext4_ext_binsearch(ip, path, lbn, first_lbn, last_lbn);
 	return (path);
 }