Re: [PATCH v2 0/5] btrfs-progs: image: Fix error when restoring multi-disk image to single disk

[David Sterba <dsterba@suse.cz>]

On Tue, Nov 27, 2018 at 04:38:23PM +0800, Qu Wenruo wrote:
> This patchset can be fetched from github:
> https://github.com/adam900710/btrfs-progs/tree/image_recover
> 
> The base commit is as usual, the latest stable tag, v4.19.
> 
> 
> Test case misc/021 will fail if using latest upstream kernel.
> 
> This is due to the enhanced code in kernel to check block group <->
> chunk <-> dev extent mapping.
> 
> This means from the very beginning, btrfs-image can't really restore a
> multi-disk image to single-disk one correctly.
> 
> The problem is, although we modified chunk item, we didn't modify block
> group item's flags or dev extents.
> 
> This patch will reset block group flags, then rebuild the whole
> dev extents by removing existing ones first, then re-add the correct
> dev extents calculated from chunk map.
> 
> Now it could pass all misc tests and fsck tests.
> 
> Changelog:
> v2:
> - Parameter list cleanup
>   * Use trans->fs_info to remove fs_info parameter
>   * Remove trans parameter for function who doesn't need
> - Merge dev extents removal code with rebuild code
> - Refactor btrfs_alloc_dev_extent() into 2 functions
>   * btrfs_insert_dev_extent() for convert and dev extent rebuild
>   * btrfs_alloc_dev_extent() for old use case
>   
> Qu Wenruo (5):
>   btrfs-progs: image: Refactor fixup_devices() to
>     fixup_chunks_and_devices()
>   btrfs-progs: image: Fix block group item flags when restoring
>     multi-device image to single device
>   btrfs-progs: volumes: Refactor btrfs_alloc_dev_extent() into two
>     functions
>   btrfs-progs: image: Remove all existing dev extents for later rebuild
>   btrfs-progs: misc-tests/021: Do extra btrfs check before mounting

Merged to devel, thanks. I've switched strerror(-ret) to the errno
pattern.