4.14-stable review patch. If anyone has any objections, please let me know.
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From: Jeff Mahoney jeffm@suse.com
commit 692826b2738101549f032a761a9191636e83be4e upstream.
Since commit fb235dc06fa (btrfs: qgroup: Move half of the qgroup accounting time out of commit trans) the assumption that btrfs_add_delayed_{data,tree}_ref can only return 0 or -ENOMEM has been false. The qgroup operations call into btrfs_search_slot and friends and can now return the full spectrum of error codes.
Fortunately, the fix here is easy since update_ref_for_cow failing is already handled so we just need to bail early with the error code.
Fixes: fb235dc06fa (btrfs: qgroup: Move half of the qgroup accounting ...) Signed-off-by: Jeff Mahoney jeffm@suse.com Reviewed-by: Edmund Nadolski enadolski@suse.com Reviewed-by: Qu Wenruo wqu@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/ctree.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)
--- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1032,14 +1032,17 @@ static noinline int update_ref_for_cow(s 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); /* -ENOMEM */ + if (ret) + return ret;
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { ret = btrfs_dec_ref(trans, root, buf, 0); - BUG_ON(ret); /* -ENOMEM */ + if (ret) + return ret; ret = btrfs_inc_ref(trans, root, cow, 1); - BUG_ON(ret); /* -ENOMEM */ + if (ret) + return ret; } new_flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF; } else { @@ -1049,7 +1052,8 @@ static noinline int update_ref_for_cow(s ret = btrfs_inc_ref(trans, root, cow, 1); else ret = btrfs_inc_ref(trans, root, cow, 0); - BUG_ON(ret); /* -ENOMEM */ + if (ret) + return ret; } if (new_flags != 0) { int level = btrfs_header_level(buf); @@ -1068,9 +1072,11 @@ static noinline int update_ref_for_cow(s ret = btrfs_inc_ref(trans, root, cow, 1); else ret = btrfs_inc_ref(trans, root, cow, 0); - BUG_ON(ret); /* -ENOMEM */ + if (ret) + return ret; ret = btrfs_dec_ref(trans, root, buf, 1); - BUG_ON(ret); /* -ENOMEM */ + if (ret) + return ret; } clean_tree_block(fs_info, buf); *last_ref = 1;