[PATCH v3 0/5] scsi_debug: add write scattered support

[Douglas Gilbert <dgilbert@interlog.com>]

While testing the WRITE SCATTERED command support in a new sg3_utils
utility (sg_write_x) it was helpful to have a target that supported
this command. This command might be attractive to other kernel
subsystems. Even if end devices don't support this command yet, it
would most likely be a performance win if SCSI LLDs supported it (by
breaking it down to a series of WRITE commands), as that would cut
down the overhead of the block layer, the ULD (e.g. sd) and the SCSI
midlevel.

Changes since v2:
  - remove over-zealous sanity check (lbdof >= bt_len) that rejected
    valid invocations
  - change a kzalloc() failure to return SCSI_MLQUEUE_HOST_BUSY as
    requested by reviewer

Changes since original version:
  - fix problem when fake_rw=1, identify media access commands
    better with following rename
  - rename FF_DIRECT_IO to FF_MEDIA_IO
  - apply reviewer suggestions (Bart Van Assche)
  - expand in-code comments

Douglas Gilbert (5):
  scsi_debug: tab, kstrto changes
  scsi_debug: fix group_number mask
  scsi_debug: do_device_access add sg offset argument
  scsi_debug: ARRAY_SIZE and FF_MEDIA_IO
  scsi_debug: add resp_write_scat function

 drivers/scsi/scsi_debug.c | 541 +++++++++++++++++++++++++++++++---------------
 1 file changed, 366 insertions(+), 175 deletions(-)

-- 
2.14.1