[PATCH 2/8] btrfs: Don't BUG_ON() errors in update_ref_for_cow()
From: Mark Fasheh <hidden>
Date: 2011-08-18 21:56:55
Subsystem:
btrfs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Chris Mason, David Sterba, Alexander Viro, Christian Brauner, Linus Torvalds
From: Mark Fasheh <redacted> 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 <redacted> --- fs/btrfs/ctree.c | 31 +++++++++++++++++++++---------- 1 files changed, 21 insertions(+), 10 deletions(-)
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 011cab3..5064930 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c@@ -331,7 +331,8 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, 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;
@@ -351,14 +352,18 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && !(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) { ret = btrfs_inc_ref(trans, root, buf, 1); - BUG_ON(ret); + if (ret) + return ret; if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { ret = btrfs_dec_ref(trans, root, buf, 0); - BUG_ON(ret); + if (ret) + return ret; + ret = btrfs_inc_ref(trans, root, cow, 1); - BUG_ON(ret); + if (ret) + return ret; } new_flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF; } else {
@@ -368,14 +373,16 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, ret = btrfs_inc_ref(trans, root, cow, 1); else ret = btrfs_inc_ref(trans, root, cow, 0); - BUG_ON(ret); + if (ret) + return ret; } if (new_flags != 0) { ret = btrfs_set_disk_extent_flags(trans, root, buf->start, buf->len, new_flags, 0); - BUG_ON(ret); + if (ret) + return ret; } } else { if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
@@ -384,9 +391,12 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, ret = btrfs_inc_ref(trans, root, cow, 1); else ret = btrfs_inc_ref(trans, root, cow, 0); - BUG_ON(ret); + if (ret) + return ret; + ret = btrfs_dec_ref(trans, root, buf, 1); - BUG_ON(ret); + if (ret) + return ret; } clean_tree_block(trans, root, buf); *last_ref = 1;
@@ -415,7 +425,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, { 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 +477,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, (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);
--
1.7.6