On Wed, Nov 13, 2019 at 11:27:21AM +0100, Johannes Thumshirn wrote:
> This series attempts to remove the BUG_ON()s in btrfs_close_one_device().
> Therefore some reorganization of btrfs_close_one_device() and
> close_fs_devices() was needed.
>
> Forthermore a new BUG_ON() had to be temporarily introduced but is removed
> again in the last patch of theis series.
>
> Although it is generally legal to return -ENOMEM on umount(2), the error
> handling up until close_ctree() as neither close_ctree() nor btrfs_put_super()
> would be able to handle the error.
>
> This series has passed fstests without any deviation from the baseline and
> also the new error handling was tested via error injection using this snippet:
>
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 7c55169c0613..c58802c9c39c 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -1069,6 +1069,9 @@ static int btrfs_close_one_device(struct btrfs_device *device)
>
> new_device = btrfs_alloc_device(NULL, &device->devid,
> device->uuid);
> + btrfs_free_device(new_device);
> + pr_err("%s() INJECTING -ENOMEM\n", __func__);
> + new_device = ERR_PTR(-ENOMEM);
> if (IS_ERR(new_device))
> return PTR_ERR(new_device);
>
> Changes to v1:
>
> Fixed the decremt of btrfs_fs_devices::seeding.
>
> In addition to this, I've added two patches changing btrfs_fs_devices::seeding
> and btrfs_fs_devices::rotating to bool, as they are in fact used as booleans.
>
> Johannes Thumshirn (7):
> btrfs: decrement number of open devices after closing the device not
> before
> btrfs: handle device allocation failure in btrfs_close_one_device()
> btrfs: handle allocation failure in strdup
> btrfs: handle error return of close_fs_devices()
> btrfs: remove final BUG_ON() in close_fs_devices()
> btrfs: change btrfs_fs_devices::seeing to bool
> btrfs: change btrfs_fs_devices::rotating to bool
I'll add the last 2 for now as they're obviously correct, the rest has
some questions that I'd like to clarify before merging.
