Btrfs: deal with free space cache errors while replaying log
So everybody who got hit by my fsync bug will still continue to hit this
BUG_ON() in the free space cache, which is pretty heavy handed. So I took a
file system that had this bug and fixed up all the BUG_ON()'s and leaks that
popped up when I tried to mount a broken file system like this. With this patch
we just fail to mount instead of panicing. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index ef4ce2c..b0a3fab 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5210,9 +5210,11 @@
u64 bytenr, u64 num_bytes)
{
struct btrfs_block_group_cache *cache;
+ int ret;
cache = btrfs_lookup_block_group(root->fs_info, bytenr);
- BUG_ON(!cache); /* Logic error */
+ if (!cache)
+ return -EINVAL;
/*
* pull in the free space cache (if any) so that our pin
@@ -5225,9 +5227,9 @@
pin_down_extent(root, cache, bytenr, num_bytes, 0);
/* remove us from the free space cache (if we're there at all) */
- btrfs_remove_free_space(cache, bytenr, num_bytes);
+ ret = btrfs_remove_free_space(cache, bytenr, num_bytes);
btrfs_put_block_group(cache);
- return 0;
+ return ret;
}
/**
@@ -6611,40 +6613,42 @@
if (!caching_ctl) {
BUG_ON(!block_group_cache_done(block_group));
ret = btrfs_remove_free_space(block_group, start, num_bytes);
- BUG_ON(ret); /* -ENOMEM */
+ if (ret)
+ goto out;
} else {
mutex_lock(&caching_ctl->mutex);
if (start >= caching_ctl->progress) {
ret = add_excluded_extent(root, start, num_bytes);
- BUG_ON(ret); /* -ENOMEM */
} else if (start + num_bytes <= caching_ctl->progress) {
ret = btrfs_remove_free_space(block_group,
start, num_bytes);
- BUG_ON(ret); /* -ENOMEM */
} else {
num_bytes = caching_ctl->progress - start;
ret = btrfs_remove_free_space(block_group,
start, num_bytes);
- BUG_ON(ret); /* -ENOMEM */
+ if (ret)
+ goto out_lock;
start = caching_ctl->progress;
num_bytes = ins->objectid + ins->offset -
caching_ctl->progress;
ret = add_excluded_extent(root, start, num_bytes);
- BUG_ON(ret); /* -ENOMEM */
}
-
+out_lock:
mutex_unlock(&caching_ctl->mutex);
put_caching_control(caching_ctl);
+ if (ret)
+ goto out;
}
ret = btrfs_update_reserved_bytes(block_group, ins->offset,
RESERVE_ALLOC_NO_ACCOUNT);
BUG_ON(ret); /* logic error */
- btrfs_put_block_group(block_group);
ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
0, owner, offset, ins, 1);
+out:
+ btrfs_put_block_group(block_group);
return ret;
}