Btrfs: remove BUG_ON()'s in btrfs_map_block

btrfs_map_block can go horribly wrong in the face of fs corruption, lets agree
to not be assholes and panic at any possible chance things are all fucked up.

Signed-off-by: Josef Bacik <jbacik@fb.com>
[ removed type casts ]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index f13e2bc..8d3ceb0 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5290,7 +5290,15 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
        stripe_nr = div64_u64(stripe_nr, stripe_len);
 
        stripe_offset = stripe_nr * stripe_len;
-       BUG_ON(offset < stripe_offset);
+       if (offset < stripe_offset) {
+               btrfs_crit(fs_info, "stripe math has gone wrong, "
+                          "stripe_offset=%llu, offset=%llu, start=%llu, "
+                          "logical=%llu, stripe_len=%llu",
+                          stripe_offset, offset, em->start, logical,
+                          stripe_len);
+               free_extent_map(em);
+               return -EINVAL;
+       }
 
        /* stripe_offset is the offset of this block in its stripe*/
        stripe_offset = offset - stripe_offset;
@@ -5531,7 +5539,13 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                                &stripe_index);
                mirror_num = stripe_index + 1;
        }
-       BUG_ON(stripe_index >= map->num_stripes);
+       if (stripe_index >= map->num_stripes) {
+               btrfs_crit(fs_info, "stripe index math went horribly wrong, "
+                          "got stripe_index=%u, num_stripes=%u",
+                          stripe_index, map->num_stripes);
+               ret = -EINVAL;
+               goto out;
+       }
 
        num_alloc_stripes = num_stripes;
        if (dev_replace_is_ongoing) {