btrfs: Don't BUG_ON() errors in update_ref_for_cow()
The only caller of update_ref_for_cow() is __btrfs_cow_block() which was
originally ignoring any return values. update_ref_for_cow() however doesn't
look like a candidate to become a void function - there are a few places
where errors can occur.
So instead I changed update_ref_for_cow() to bubble all errors up (instead
of BUG_ON). __btrfs_cow_block() was then updated to catch and BUG_ON() any
errors from update_ref_for_cow(). The end effect is that we have no change
in behavior, but about 8 different places where a BUG_ON(ret) was removed.
Obviously a future patch will have to address the BUG_ON() in
__btrfs_cow_block().
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 9d472c2..e2e43c0 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -331,7 +331,8 @@
if (btrfs_block_can_be_shared(root, buf)) {
ret = btrfs_lookup_extent_info(trans, root, buf->start,
buf->len, &refs, &flags);
- BUG_ON(ret);
+ if (ret)
+ return ret;
BUG_ON(refs == 0);
} else {
refs = 1;
@@ -375,7 +376,8 @@
buf->start,
buf->len,
new_flags, 0);
- BUG_ON(ret);
+ if (ret)
+ return ret;
}
} else {
if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
@@ -415,7 +417,7 @@
{
struct btrfs_disk_key disk_key;
struct extent_buffer *cow;
- int level;
+ int level, ret;
int last_ref = 0;
int unlock_orig = 0;
u64 parent_start;
@@ -467,7 +469,8 @@
(unsigned long)btrfs_header_fsid(cow),
BTRFS_FSID_SIZE);
- update_ref_for_cow(trans, root, buf, cow, &last_ref);
+ ret = update_ref_for_cow(trans, root, buf, cow, &last_ref);
+ BUG_ON(ret);
if (root->ref_cows)
btrfs_reloc_cow_block(trans, root, buf, cow);