Hi all - Here's my current error handling patchset, against David's integration branch. Almost all of this patchset is preparing for actual error handling. Before we start in on that work, I'm trying to reduce the surface we need to worry about. It turns out that there is a ton of code that returns an error code but never actually reports an error.
The patchset has grown to 66 patches. 46 of them change functions that currently return int to return void. Many of them didn't even have the error codes checked in the caller to begin with. 11 of the patches push error codes up into the caller. The remaining 9 patches do: - Add a btrfs_panic facility, with a mount option to select BUG or panic - Catch tree operation failures - Simplify/add some wrapper functions The biggest change, which will probably merit some discussion, is the introduction of slab-backed mempools in the delayed ref code. I expect to use this technique in other areas of the code to deal with deep failures that are impossible to recover gracefully from. Rather than returning -ENOMEM, we keep a page's worth of objects around for each node type. That allows the callers to be drastically simplified. There's no reason in particular to start with the delayed ref code, it's just where I happened to do it. Changes since v3 in order of impact: - Fixed an issue in ("btrfs: clear_extent_bit error push-up") where a positive error code returned by clear_extent_bit was being passed to callers of btrfs_direct_IO. The callers intepreted it as an error and xfstests reported corruption in test 130. - Push-up patches have added __must_check to their prototypes so that new callers are forced to properly handle the error conditions, even if it's also with BUG_ON. Some callers weren't checking error codes at all and this will prevent those types of issues from being re-introduced. - Added error push-up and tree locking check for convert_extent_bit. - Moved btrfs_drop_snapshot checks into the patch that changed it to return int. This is also available in my git repository at: git://git.jeffreymahoney.com/linux/btrfs-unstable for-david-v5 It depends on git://repo.or.cz/linux-2.6/btrfs-unstable.git, starting with commit f2ab07c6 ("Btrfs: fix the amount of space reserved for unlink"). I can rebase if necessary. -Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html