On 2021/9/17 19:19, David Sterba wrote:

On Wed, Sep 15, 2021 at 03:17:16PM +0800, Qu Wenruo wrote:

quoted

The structure btrfs_bio is used by two different sites:

- bio->bi_private for mirror based profiles
   For those profiles (SINGLE/DUP/RAID1*/RAID10), this structures records

Why is SINGLE here?

For single we use the same routine as RAID1/DUP/etc, it's
submit_stripe_bio() doing the remapping.

Thus there is really only two types, non-RAID56 and RAID56.

Thanks,
Qu