fix extent_goto for non-0 leaf levels

The logic for stopping at the right level in extent_goto was wrong,
so if you asked it to go to any level other than 0 (the leaf
level) it would fail.

Also add this argument to the tst_extents goto command to test it.

(I thought this was a failure in my split code but it was this
helper that was causing problems...)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/lib/ext2fs/extent.c b/lib/ext2fs/extent.c
index e7b7e85..b76abdc 100644 (file)
--- a/lib/ext2fs/extent.c
+++ b/lib/ext2fs/extent.c
@@ -556,6 +556,9 @@ errcode_t ext2fs_extent_free_path(ext2_extent_path_t path)
 /*
  * Go to the node at leaf_level which contains logical block blk.
  *
+ * leaf_level is height from the leaf node level, i.e.
+ * leaf_level 0 is at leaf node, leaf_level 1 is 1 above etc.
+ *
  * If "blk" has no mapping (hole) then handle is left at last
  * extent before blk.
  */
@@ -569,9 +572,15 @@ static errcode_t extent_goto(ext2_extent_handle_t handle,
        if (retval)
                return retval;
 
+       if (leaf_level > handle->max_depth) {
+               dbg_printf("leaf level %d greater than tree depth %d\n",
+                       leaf_level, handle->max_depth);
+               return EXT2_ET_OP_NOT_SUPPORTED;
+       }
+
        dbg_print_extent("root", &extent);
        while (1) {
-               if (handle->level - leaf_level == handle->max_depth) {
+               if (handle->max_depth - handle->level == leaf_level) {
                        /* block is in this &extent */
                        if ((blk >= extent.e_lblk) &&
                            (blk < extent.e_lblk + extent.e_len))
@@ -1140,6 +1149,7 @@ void do_goto_block(int argc, char **argv)
        errcode_t               retval;
        int                     op = EXT2_EXTENT_NEXT_LEAF;
        blk_t                   blk;
+       int                     level = 0;
 
        if (check_fs_open(argv[0]))
                return;
@@ -1149,18 +1159,23 @@ void do_goto_block(int argc, char **argv)
                return;
        }
 
-       if (argc != 2) {
-               fprintf(stderr, "%s block\n", argv[0]);
+       if (argc < 2 || argc > 3) {
+               fprintf(stderr, "%s block [level]\n", argv[0]);
                return;
        }
 
        if (strtoblk(argv[0], argv[1], &blk))
                return;
 
-       retval = ext2fs_extent_goto(current_handle, (blk64_t) blk);
+       if (argc == 3)
+               if (strtoblk(argv[0], argv[2], &level))
+                       return;
+
+       retval = extent_goto(current_handle, level, (blk64_t) blk);
+
        if (retval) {
-               com_err(argv[0], retval, "while trying to go to block %lu",
-                       blk);
+               com_err(argv[0], retval, "while trying to go to block %lu, level %d",
+                       blk, level);
                return;
        }