From: Eric Sandeen <sandeen@redhat.com>
Date: Tue, 5 Jun 2012 18:25:57 +0000 (-0500)
Subject: xfs_repair: handle fragmented multiblock dir2 in process_leaf_node_dir2()
X-Git-Tag: v3.1.9-rc1~14
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9fe1cc862159b50651baa68a6b60ae0819d4f871;p=thirdparty%2Fxfsprogs-dev.git

xfs_repair: handle fragmented multiblock dir2 in process_leaf_node_dir2()

process_leaf_node_dir2() had the following loop:

	while ((dbno = blkmap_next_off(blkmap, ndbno, &t)) < mp->m_dirleafblk) {
		...
		ndbno = dbno + mp->m_dirblkfsbs - 1;
		...
	}

which does not account for fragmented multiblock dir2.

ndbno was blindly being advanced by m_dirblkfsbs, but then
blkmap_next_off() would return the logical block of the next
mapped extent in blkmap, which may be within the current
(fragmented) dir2 multi-block, not the next multi-block,
because the extent index t hadn't been advanced.

Fix this by calling blkmap_next_off() until ndbno has advanced
into the next multiblock dir2 block, thereby keeping
the extent index t straight while properly advancing
ndbno.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
---

diff --git a/repair/dir2.c b/repair/dir2.c
index f9562d79f..7a614a8d6 100644
--- a/repair/dir2.c
+++ b/repair/dir2.c
@@ -2003,7 +2003,11 @@ process_leaf_node_dir2(
 	ndbno = NULLDFILOFF;
 	while ((dbno = blkmap_next_off(blkmap, ndbno, &t)) < mp->m_dirleafblk) {
 		nex = blkmap_getn(blkmap, dbno, mp->m_dirblkfsbs, &bmp, &lbmp);
-		ndbno = dbno + mp->m_dirblkfsbs - 1;
+		/* Advance through map to last dfs block in this dir block */
+		ndbno = dbno;
+		while (ndbno < dbno + mp->m_dirblkfsbs - 1) {
+			ndbno = blkmap_next_off(blkmap, ndbno, &t);
+		}
 		if (nex == 0) {
 			do_warn(
 _("block %" PRIu64 " for directory inode %" PRIu64 " is missing\n"),