[Qemu-devel] [PATCH v4 00/24] SCSI subsystem improvements

[Paolo Bonzini]

This series includes the following improvements to the SCSI subsystem:

1) introduction of SCSIBusOps that generalize the existing
command_complete callback;

2) widespread use of the SCSIRequest abstraction, with simpler memory
management (refcounting) and with various common idioms converted into
simple C functions instead of duplicating them all over the place;

3) support for autosense.

Some patches are from Hannes Reinecke's megasas patchset posted last
November, forward ported and applied to the new vSCSI controller as
well.

I already planned the following two series too:

1) adding support for zerocopy.  Previous attempts were rejected
because they were applied to real devices (thus making for example an
IOMMU hard to impossible).  However, for PV devices zerocopy should be
uncontroversial---and it is a must to get competitive performance WRT
virtio-blk.  I'll use vmw-pvscsi for the first implementation and for
benchmarking.

2) adding support for multiple LUNs; see recently posted RFC for this.

After this I'll work on the virtio-scsi device model.

Testing:
- RHEL6.1 install complete to scsi-disk with lsi, from scsi-generic CD
- iozone run with lsi on scsi-disk target
- RHEL6.1 install to usb-msd from IDE CD is too slow, but it manages to
  format /boot in ~10 minutes with or without the patches
- RHEL6.1 install with vscsi with scsi-disk CD and installation disk
  hung at the same place with or without the series

esp is only compile tested.

Please review and apply.

v3->v4:
    renamed scsi_req_kick to scsi_req_continue.  Changed SCSIBusOps to
    pointer.  Removed scsi_req_free, merged it into scsi_req_unref.
    Added head comments for some functions.  Renamed arguments to
    HBA callbacks.  Added patches 23 and 24

v2->v3:
    included fixes for Jonathan Nieder's recently reported bug

v1->v2:
    rebased, added patch 21

Hannes Reinecke (4):
  scsi: Use 'SCSIRequest' directly
  scsi: Update sense code handling
  scsi: Implement 'get_sense' callback
  scsi-disk: add data direction checking

Paolo Bonzini (20):
  scsi: add tracing of scsi requests
  scsi-generic: Remove bogus double complete
  scsi: introduce scsi_req_data
  scsi: introduce SCSIBusOps
  scsi: reference-count requests
  lsi: extract lsi_find_by_tag
  scsi: commonize purging requests
  scsi: introduce scsi_req_abort
  scsi: introduce scsi_req_cancel
  scsi: use scsi_req_complete
  scsi: do not call send_command directly
  scsi: introduce scsi_req_new
  scsi: introduce scsi_req_continue
  scsi: introduce scsi_req_get_buf
  scsi: make write_data return void
  scsi-generic: Handle queue full
  esp: rename sense to status
  scsi: split command_complete callback in two
  scsi: rename arguments to the new callbacks
  scsi: ignore LUN field in the CDB

 hw/esp.c          |  119 ++++++++++++++----------
 hw/lsi53c895a.c   |  188 +++++++++++++++++++++++--------------
 hw/scsi-bus.c     |  214 +++++++++++++++++++++++++++++++++++++++----
 hw/scsi-disk.c    |  265 ++++++++++++++++++++++-------------------------------
 hw/scsi-generic.c |  220 +++++++++++++++++++++-----------------------
 hw/scsi.h         |   91 ++++++++++++++----
 hw/spapr_vscsi.c  |  185 +++++++++++++++++++++----------------
 hw/usb-msd.c      |  120 ++++++++++++++----------
 trace-events      |    8 ++
 9 files changed, 843 insertions(+), 567 deletions(-)

-- 
1.7.4.4