[0/3] btrfs: enhancement to pass generic/563

Message

Qu Wenruo Jan. 14, 2025, 9:52 a.m. UTC

The test case generic/563 on aarch64 with 64K page size and 4K fs block
size will fail with btrfs, but not EXT4 nor XFS.

The detailed reason is explained in the last patch, the TL;DR is that
btrfs is not handling block aligned buffered write in an optimized way
for subpage cases (block size < page size).

The first patch is a refactor in preparation for the new enhancement.
The second patch is to solve the possible deadlock which can only be
exposed by the final enhancement.

Eventually the last patch will enable the enhancement and pass the
generic/563.

This series used to be mixed into this series:
https://lore.kernel.org/linux-btrfs/[e-mail]/

But unfortunately the ordered extent double accounting fix is not
solving all problems.
And since all the ordered extents double accounting is properly fixed in
for-next, we can come back to the subpage enhancement and focus on it.

Qu Wenruo (3):
  btrfs: make btrfs_do_readpage() to do block-by-block read
  btrfs: avoid deadlock when reading a partial uptodate folio
  btrfs: allow buffered write to avoid full page read if it's block
    aligned

 fs/btrfs/defrag.c       |  2 +-
 fs/btrfs/direct-io.c    |  2 +-
 fs/btrfs/extent_io.c    | 44 +++++++++++----------------
 fs/btrfs/file.c         | 13 ++++----
 fs/btrfs/inode.c        |  6 ++--
 fs/btrfs/ordered-data.c | 67 ++++++++++++++++++++++++++++++++++++-----
 fs/btrfs/ordered-data.h |  8 +++--
 7 files changed, 94 insertions(+), 48 deletions(-)