Btrfs: deal with enomem in the rewind path
We can get ENOMEM trying to allocate dummy bufs for the rewind operation of the
tree mod log. Instead of BUG_ON()'ing in this case pass up ENOMEM. I looked
back through the callers and I'm pretty sure I got everybody who did BUG_ON(ret)
in this path. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 0d5c686..1dd8a71 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1211,7 +1211,11 @@
BUG_ON(tm->slot != 0);
eb_rewin = alloc_dummy_extent_buffer(eb->start,
fs_info->tree_root->nodesize);
- BUG_ON(!eb_rewin);
+ if (!eb_rewin) {
+ btrfs_tree_read_unlock(eb);
+ free_extent_buffer(eb);
+ return NULL;
+ }
btrfs_set_header_bytenr(eb_rewin, eb->start);
btrfs_set_header_backref_rev(eb_rewin,
btrfs_header_backref_rev(eb));
@@ -1219,7 +1223,11 @@
btrfs_set_header_level(eb_rewin, btrfs_header_level(eb));
} else {
eb_rewin = btrfs_clone_extent_buffer(eb);
- BUG_ON(!eb_rewin);
+ if (!eb_rewin) {
+ btrfs_tree_read_unlock(eb);
+ free_extent_buffer(eb);
+ return NULL;
+ }
}
btrfs_tree_read_unlock(eb);
@@ -2772,6 +2780,10 @@
BTRFS_READ_LOCK);
}
b = tree_mod_log_rewind(root->fs_info, b, time_seq);
+ if (!b) {
+ ret = -ENOMEM;
+ goto done;
+ }
p->locks[level] = BTRFS_READ_LOCK;
p->nodes[level] = b;
} else {