[PATCH v2 00/14] folio support for sync I/O in RAID

From: Li Nan <[email protected]>

This patchset adds folio support to sync operations in raid1/10.
Previously, we used 16 * 4K pages for 64K sync I/O. With this change,
we'll use a single 64K folio instead. Using folios reduces
resync/recovery time by 20% on HDD.

This is the first step towards full folio support in RAID. Going forward,
I will replace the remaining page-based usage with folio.

The patchset was tested with mdadm. Additional fault injection stress tests
were run under file systems.

v2:
 - Remove patch "md: use folio for bb_folio". It will be included in
   a later patch set
 - In patch 5:
    1) fix typo
    2) rewrite the logic of copying data in process_checks()
    3) rename resync_get_all_folio() to resync_get_folio()
    4) s/resync_pages *rps/resync_folio *rfs/g in
       raid1_alloc_init_r1buf() and raid10_alloc_init_r10buf()
 - Subsequent patches: Adapting conflicts caused by patch 5

Li Nan (14):
  md/raid1,raid10: clean up of RESYNC_SECTORS
  md: introduce sync_folio_io for folio support in RAID
  md/raid1: use folio for tmppage
  md/raid10: use folio for tmppage
  md/raid1,raid10: use folio for sync path IO
  md: Clean up folio sync support related code
  md/raid1: clean up useless sync_blocks handling in raid1_sync_request
  md/raid1: fix IO error at logical block size granularity
  md/raid10: fix IO error at logical block size granularity
  md/raid1,raid10: clean up resync_fetch_folio
  md: clean up resync_free_folio
  md/raid1: clean up sync IO size calculation in raid1_sync_request
  md/raid10: clean up sync IO size calculation in raid10_sync_request
  md/raid1,raid10: fall back to smaller order if sync folio alloc fails

 drivers/md/md.h       |   2 +
 drivers/md/raid1.h    |   2 +-
 drivers/md/raid10.h   |   2 +-
 drivers/md/md.c       |  29 +++-
 drivers/md/raid1-10.c |  81 ++++-------
 drivers/md/raid1.c    | 233 ++++++++++++++-----------------
 drivers/md/raid10.c   | 315 ++++++++++++++++++++----------------------
 7 files changed, 308 insertions(+), 356 deletions(-)

-- 
2.39.2