xfs_repair: continue after xfs_bunmapi deadlock avoidance

xfs_bunmapi can legitimately return before all work is done, to
avoid deadlocks across AGs.

Sadly nobody told xfs_repair, so it fires an assert if this happens:

 phase6.c:1410: longform_dir2_rebuild: Assertion `done' failed.

Fix this by calling back in until all work is done, as we do
in the kernel.

Fixes: 5a8bcc ("xfs: fix multi-AG deadlock in xfs_bunmapi")
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1641116
Reported-by: Tomasz Torcz <tomek@pipebreaker.pl>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/repair/phase6.c b/repair/phase6.c
index dc1cf8b9d4bbf3caade02d84f18326f66a02aab4..9477bc2527f3b10e9932705b7a8fe5c444f928e9 100644 (file)
--- a/repair/phase6.c
+++ b/repair/phase6.c
@@ -1317,7 +1317,7 @@ longform_dir2_rebuild(
        xfs_fileoff_t           lastblock;
        xfs_inode_t             pip;
        dir_hash_ent_t          *p;
-       int                     done;
+       int                     done = 0;
 
        /*
         * trash directory completely and rebuild from scratch using the
@@ -1352,14 +1352,25 @@ longform_dir2_rebuild(
                        error);
 
        /* free all data, leaf, node and freespace blocks */
-       error = -libxfs_bunmapi(tp, ip, 0, lastblock, XFS_BMAPI_METADATA, 0,
-                               &done);
-       if (error) {
-               do_warn(_("xfs_bunmapi failed -- error - %d\n"), error);
-               goto out_bmap_cancel;
-       }
-
-       ASSERT(done);
+       while (!done) {
+              error = -libxfs_bunmapi(tp, ip, 0, lastblock, XFS_BMAPI_METADATA,
+                                      0, &done);
+              if (error) {
+                      do_warn(_("xfs_bunmapi failed -- error - %d\n"), error);
+                      goto out_bmap_cancel;
+              }
+              error = -libxfs_defer_finish(&tp);
+              if (error) {
+                      do_warn(("defer_finish failed -- error - %d\n"), error);
+                      goto out_bmap_cancel;
+              }
+              /*
+               * Close out trans and start the next one in the chain.
+               */
+              error = -libxfs_trans_roll_inode(&tp, ip);
+              if (error)
+                       goto out_bmap_cancel;
+        }
 
        error = -libxfs_dir_init(tp, ip, &pip);
        if (error) {