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

The branch can be fetched from github, and is the preferred way to grab
the code, as this patchset changed quite a lot of code.
https://github.com/adam900710/linux/tree/chunk_refactor

There are two structure, btrfs_io_bio and btrfs_bio, which have very
similar names but completely different meanings.

Btrfs_io_bio mostly works at logical bytenr layer (its
bio->bi_iter.bi_sector points to btrfs logical bytenr), and just
contains extra info like csum and mirror_num.

And btrfs_io_bio is in fact the most utilized bio, as all data/metadata
IO is using btrfs_io_bio.

While btrfs_bio is completely a helper structure for mirrored IO
submission (utilized by SINGLE/DUP/RAID1/RAID10), and contains RAID56
maps for RAID56 (it doesn't utilize this structure for IO submission
tracking).

Such naming is completely anti-human.

So this patchset will do the following renaming:

- btrfs_bio -> btrfs_io_context
  Since it's not really used by all bios (only mirrored profiles utilize
  it), and it contains extra info for RAID56, it's not proper to name it
  with _bio suffix.

  Later we can integrate btrfs_io_context pointer into the new
  btrfs_bio.

- btrfs_io_bio -> btrfs_logical_bio
  It is intentional not to reuse "btrfs_bio", which could cause
  confusion for later backport.

Changelog:
v2:
- Rename btrfs_bio to btrfs_io_context (bioc)
- Rename btrfs_io_bio to btrfs_bio
  Both suggested by Nikolay

v3:
- Fixes whiespace problems
  Caused by "dwi" vim commands

- Update several modified comments

- Rename btrfs_io_bio to btrfs_logical_bio
  To avoid backport confusion.

Qu Wenruo (3):
  btrfs: rename btrfs_bio to btrfs_io_context
  btrfs: remove btrfs_bio_alloc() helper
  btrfs: rename struct btrfs_io_bio to btrfs_logical_bio

Added to misc-next, thanks.