Hi,

This is a *compile only RFC* which adds a generic helper to initialize
the various fields of the bio that is repeated all the places in
file-systems, block layer, and drivers.

The new helper allows callers to initialize non-optional members of bio
such as bdev, sector, op, opflags, max_bvecs and gfp_mask by
encapsulating new bio allocation with bio alloc with initialization
at one place.

The objective of this RFC is to only start a discussion, this it not 
completely tested at all.

-ck                         

Chaitanya Kulkarni (34):
  block: move common code into blk_next_bio()
  block: introduce and use bio_new
  drdb: use bio_new in drdb
  drdb: use bio_new() in submit_one_flush
  xen-blkback: use bio_new
  zram: use bio_new
  dm: use bio_new in dm-log-writes
  dm-zoned: use bio_new in get_mblock_slow
  dm-zoned: use bio_new in dmz_write_mblock
  dm-zoned: use bio_new in dmz_rdwr_block
  nvmet: use bio_new in nvmet_bdev_execute_rw
  scsi: target/iblock: use bio_new
  block: use bio_new in __blkdev_direct_IO
  fs/buffer: use bio_new in submit_bh_wbc
  fscrypt: use bio_new in fscrypt_zeroout_range
  fs/direct-io: use bio_new in dio_bio_alloc
  iomap: use bio_new in iomap_dio_zero
  iomap: use bio_new in iomap_dio_bio_actor
  fs/jfs/jfs_logmgr.c: use bio_new in lbmRead
  fs/jfs/jfs_logmgr.c: use bio_new in lbmStartIO
  fs/jfs/jfs_metapage.c: use bio_new in metapage_writepage
  fs/jfs/jfs_metapage.c: use bio_new in metapage_readpage
  fs/mpage.c: use bio_new mpage_alloc
  fs/nilfs: use bio_new nilfs_alloc_seg_bio
  ocfs/cluster: use bio_new in dm-log-writes
  xfs: use bio_new in xfs_rw_bdev
  xfs: use bio_new in xfs_buf_ioapply_map
  zonefs: use bio_new
  power/swap: use bio_new in hib_submit_io
  hfsplus: use bio_new in hfsplus_submit_bio()
  iomap: use bio_new in iomap_readpage_actor
  mm: use bio_new in __swap_writepage
  mm: use bio_new in swap_readpage
  mm: add swap_bio_new common bio helper

 block/blk-lib.c                     | 34 ++++++++++-------------------
 block/blk-zoned.c                   |  4 +---
 block/blk.h                         |  5 +++--
 drivers/block/drbd/drbd_receiver.c  | 12 +++++-----
 drivers/block/xen-blkback/blkback.c | 20 +++++++++++------
 drivers/block/zram/zram_drv.c       |  5 ++---
 drivers/md/dm-log-writes.c          | 30 +++++++++----------------
 drivers/md/dm-zoned-metadata.c      | 18 +++++----------
 drivers/nvme/target/io-cmd-bdev.c   |  9 +++-----
 drivers/target/target_core_iblock.c |  5 ++---
 fs/block_dev.c                      |  6 ++---
 fs/buffer.c                         | 16 ++++++--------
 fs/crypto/bio.c                     |  5 ++---
 fs/direct-io.c                      |  6 ++---
 fs/hfsplus/wrapper.c                |  5 +----
 fs/iomap/buffered-io.c              | 12 +++++-----
 fs/iomap/direct-io.c                | 11 ++++------
 fs/jfs/jfs_logmgr.c                 | 13 ++++-------
 fs/jfs/jfs_metapage.c               | 15 +++++--------
 fs/mpage.c                          | 18 +++++----------
 fs/nilfs2/segbuf.c                  | 10 ++-------
 fs/ocfs2/cluster/heartbeat.c        |  6 ++---
 fs/xfs/xfs_bio_io.c                 |  7 ++----
 fs/xfs/xfs_buf.c                    |  6 ++---
 fs/zonefs/super.c                   |  6 ++---
 include/linux/bio.h                 | 25 +++++++++++++++++++++
 kernel/power/swap.c                 |  7 +++---
 mm/page_io.c                        | 30 +++++++++++++------------
 28 files changed, 151 insertions(+), 195 deletions(-)

-- 
2.22.1