[PATCH v2 0/9] btrfs: prepare for variable stripe_len

[Qu Wenruo <wqu@suse.com>]

[CHANGELOG]
v2:
- Use IS_ALINGED() when possible
  Mostly affecting zoned.c

- Refactor is_same_chunk_map()
  Not only reduce the length of the parameter list, but also make it
  easier to expand, with extra unlikely() calls.

- Refactor alloc_scrub_bbio()
  Since the @private is always a scrub_stripe pointer, use scrub_stripe
  as the type instead, so we can grab stripe_len without introducing a
  new parameter.

All are suggested by Johannes.


This is a preparation patchset, to support a stripe_len that is not
64KiB.

This is for the future variable stripe length RAID56 feature, where
RAID56_VSL profile is allowed for data chunks, and the stripe_len can be
as small as sectorsize, meanwhile data IO are kept to be aligned to
data_size, which is power of 2, and larger than sector size.

Finally, RAID56_VSL will always have a number of devices that nr_data ==
data_size / sector_size.

So that's why we want a variable stripe_len.

This series does all the preparation, including supporting stripe_len <
PAGE_SIZE.

For now, tree-checker will still reject stripe_len != 64K, but that
limit will be removed when RAID56_VSL feature is introduced and can be
properly tested.


Qu Wenruo (9):
  btrfs: reduce the width of num_stripes and sub_stripes
  btrfs: load the on-disk btrfs_chunk::stripe_len
  btrfs: add btrfs_io_context::stripe_len and load it
  btrfs: change scrub to use stripe_len
  btrfs: add a new 'stripe_len' parameter to btrfs_stripe_nr_to_offset()
  btrfs: convert volumes.c and block-group.c to use map->stripe_len
  btrfs: convert raid56.c to use rbio->bioc->stripe_len
  btrfs: convert zoned.c to use map->stripe_len
  btrfs: introduce extra limits on btrfs_chunk::stripe_len

 fs/btrfs/block-group.c  |   9 +--
 fs/btrfs/raid56.c       |  57 ++++++++++++------
 fs/btrfs/raid56.h       |   7 +--
 fs/btrfs/scrub.c        | 129 ++++++++++++++++++++++++++--------------
 fs/btrfs/tree-checker.c |  13 +++-
 fs/btrfs/volumes.c      |  95 +++++++++++++++++++----------
 fs/btrfs/volumes.h      |  16 +++--
 fs/btrfs/zoned.c        |  56 +++++++++--------
 8 files changed, 246 insertions(+), 136 deletions(-)

-- 
2.56.0