[PATCHv3,00/40] SCSI result cleanup, part 2

Message ID 20210427083046.31620-1-hare@suse.de
Headers show
Series
  • SCSI result cleanup, part 2
Related show

Message

Hannes Reinecke April 27, 2021, 8:30 a.m.
Hi all,

here is now my alternative approach on how the SCSI result could be
cleaned up. It's based on the observation that two fields (namely
driver_byte and message_byte) are essentially unused.
The driver byte really is an unloved thing, with very few drivers
using it, and not really consistent, either.
It's only DRIVER_SENSE which has a meaning for userspace, and that
just indicates if a sense code is present; as such it can easily
inferred by looking at the sense code itself.
The message byte is a different story, as it's being used internally
by some SCSI parallel drivers. But even here, in the end the message
byte is only ever relevant for SCSI EH, and that just checks if
any message byte is set apart from COMMAND_COMPLETE.
And we have the SCp.Message field, which can be used to hold the
message values for drivers which had been using the message byte
in the SCSI result. If we do that the message byte itself becomes
irrelevant and can be dropped, too.

So with this approach we can stop using the driver_byte and the
message_byte values in the SCSI result, which means we only
have two values (host byte and status byte) left to deal with.

My plan here is move every driver to use accessors for the
remaining bytes in the SCSI result, and with that move the
SCSI result over into two separate values.

A patchset implementing this can be found at:

git://git.kernel.org/pub/scm/linux/kernel/hare/scsi-devel.git
scsi-result-rework

This patchset is the first part of that; later parts will
be posted once this one is accepted.

As it has been noted that there is a confusion between
'status_byte()' (which returns the linux status code) and
'get_status_byte()' (which returns the SAM status code) I've
added another patch to rip out the linux-specific SCSI
status code; they have been obsoleted years ago and it's
time for them to go.

As usual, comments and reviews are welcome.

Changes to v2:
- Include reviews from Finn Thain and Christoph
- Add a new patch to modify response handling in
  scsi_mode_sense() as suggested by Christoph

Changes to v1:
- Drop patches not relevant to this series
- Include reviews from Bart and Doug Gilbert
- Add patch to remove status_byte()

Hannes Reinecke (40):
  st: return error code in st_scsi_execute()
  scsi_ioctl: return error code when blk_rq_map_kern() fails
  scsi: Fixup calling convention for scsi_mode_sense()
  scsi: reshuffle response handling in scsi_mode_sense()
  scsi_dh_alua: check for negative result value
  scsi: stop using DRIVER_ERROR
  scsi: introduce scsi_build_sense()
  scsi: introduce scsi_status_is_check_condition()
  scsi: Kill DRIVER_SENSE
  scsi: do not use DRIVER_INVALID
  scsi_error: use DID_TIME_OUT instead of DRIVER_TIMEOUT
  xen-scsiback: use DID_ERROR instead of DRIVER_ERROR
  xen-scsifront: compability status handling
  scsi: Drop the now obsolete driver_byte definitions
  NCR5380: Fold SCSI message ABORT onto DID_ABORT
  scsi: add get_{status,host}_byte() accessor function
  scsi: add scsi_msg_to_host_byte()
  dc395: use standard macros to set SCSI result
  dc395: translate message bytes
  qlogicfas408: make ql_pcmd() a void function
  qlogicfas408: whitespace cleanup
  qlogicfas408: translate message to host byte status
  nsp32: whitespace cleanup
  nsp32: do not set message byte
  wd33c93: translate message byte to host byte
  mesh: translate message to host byte status
  acornscsi: remove acornscsi_reportstatus()
  acornscsi: translate message byte to host byte
  aha152x: modify done() to use separate status bytes
  aha152x: do not set message byte when calling scsi_done()
  advansys: do not set message byte in SCSI status
  fas216: translate message to host byte status
  fas216: Use get_status_byte() to avoid using linux-specific status
    codes
  FlashPoint: Use standard SCSI definitions
  fdomain: drop last argument to fdomain_finish_cmd()
  fdomain: translate message to host byte status
  scsi: drop message byte helper
  scsi: kill message byte
  target: use standard SAM status types
  scsi: drop obsolete linux-specific SCSI status codes

 Documentation/scsi/scsi_mid_low_api.rst     |   7 +-
 block/bsg-lib.c                             |   2 +-
 block/bsg.c                                 |   4 +-
 block/scsi_ioctl.c                          |  13 +-
 drivers/ata/libata-scsi.c                   |  30 +-
 drivers/infiniband/ulp/srp/ib_srp.c         |   2 +-
 drivers/s390/scsi/zfcp_scsi.c               |   5 +-
 drivers/scsi/3w-9xxx.c                      |   2 +-
 drivers/scsi/3w-xxxx.c                      |   6 +-
 drivers/scsi/53c700.c                       |   6 +-
 drivers/scsi/FlashPoint.c                   | 165 ++++----
 drivers/scsi/NCR5380.c                      |  10 +-
 drivers/scsi/advansys.c                     |   4 -
 drivers/scsi/aha152x.c                      |  33 +-
 drivers/scsi/aic7xxx/aic79xx_osm.c          |  19 +-
 drivers/scsi/aic7xxx/aic7xxx_osm.c          |   1 -
 drivers/scsi/arcmsr/arcmsr_hba.c            |   5 +-
 drivers/scsi/arm/acornscsi.c                |  46 +--
 drivers/scsi/arm/fas216.c                   |  15 +-
 drivers/scsi/ch.c                           |   5 +-
 drivers/scsi/constants.c                    |  15 -
 drivers/scsi/cxlflash/superpipe.c           |   3 +-
 drivers/scsi/dc395x.c                       |  80 ++--
 drivers/scsi/device_handler/scsi_dh_alua.c  |   8 +-
 drivers/scsi/esas2r/esas2r_main.c           |   2 +-
 drivers/scsi/esp_scsi.c                     |   4 +-
 drivers/scsi/fdomain.c                      |  22 +-
 drivers/scsi/hptiop.c                       |   2 +-
 drivers/scsi/ibmvscsi/ibmvscsi.c            |   2 +-
 drivers/scsi/libiscsi.c                     |   5 +-
 drivers/scsi/lpfc/lpfc_scsi.c               |  54 +--
 drivers/scsi/megaraid.c                     |  20 +-
 drivers/scsi/megaraid/megaraid_mbox.c       |  25 +-
 drivers/scsi/megaraid/megaraid_sas_base.c   |   2 -
 drivers/scsi/megaraid/megaraid_sas_fusion.c |   1 -
 drivers/scsi/mesh.c                         |   9 +-
 drivers/scsi/mpt3sas/mpt3sas_scsih.c        |  14 +-
 drivers/scsi/mvumi.c                        |  10 +-
 drivers/scsi/myrb.c                         |  64 +--
 drivers/scsi/myrs.c                         |   9 +-
 drivers/scsi/nsp32.c                        | 419 +++++++++++---------
 drivers/scsi/ps3rom.c                       |   7 +-
 drivers/scsi/qla2xxx/qla_isr.c              |  15 +-
 drivers/scsi/qlogicfas408.c                 | 137 ++++---
 drivers/scsi/scsi.c                         |  11 +-
 drivers/scsi/scsi_debug.c                   |  15 +-
 drivers/scsi/scsi_error.c                   |  70 ++--
 drivers/scsi/scsi_ioctl.c                   |   7 +-
 drivers/scsi/scsi_lib.c                     | 119 +++---
 drivers/scsi/scsi_logging.c                 |  10 +-
 drivers/scsi/scsi_scan.c                    |   6 +-
 drivers/scsi/scsi_transport_sas.c           |   9 +-
 drivers/scsi/scsi_transport_spi.c           |   2 +-
 drivers/scsi/sd.c                           |  63 +--
 drivers/scsi/sd_zbc.c                       |   3 +-
 drivers/scsi/sg.c                           |   9 +-
 drivers/scsi/smartpqi/smartpqi_init.c       |   3 +-
 drivers/scsi/sr.c                           |   4 +-
 drivers/scsi/sr_ioctl.c                     |   6 +-
 drivers/scsi/st.c                           |   8 +-
 drivers/scsi/stex.c                         |   9 +-
 drivers/scsi/sym53c8xx_2/sym_glue.c         |   6 +-
 drivers/scsi/ufs/ufshcd.c                   |   2 +-
 drivers/scsi/virtio_scsi.c                  |   5 +-
 drivers/scsi/vmw_pvscsi.c                   |   6 -
 drivers/scsi/wd33c93.c                      |  43 +-
 drivers/scsi/xen-scsifront.c                |   8 +-
 drivers/target/loopback/tcm_loop.c          |   1 -
 drivers/target/target_core_alua.c           |   6 +-
 drivers/target/target_core_iblock.c         |   2 +-
 drivers/target/target_core_pr.c             |   8 +-
 drivers/target/target_core_pscsi.c          |   2 +-
 drivers/target/target_core_sbc.c            |  10 +-
 drivers/target/target_core_spc.c            |  14 +-
 drivers/target/target_core_xcopy.c          |   2 +-
 drivers/usb/storage/cypress_atacb.c         |   4 +-
 drivers/xen/xen-scsiback.c                  |  17 +-
 include/scsi/scsi.h                         |  38 +-
 include/scsi/scsi_cmnd.h                    |  38 +-
 include/scsi/scsi_proto.h                   |  22 +-
 include/scsi/sg.h                           |  33 ++
 include/trace/events/scsi.h                 |  48 +--
 82 files changed, 908 insertions(+), 1070 deletions(-)

Comments

Christoph Hellwig April 29, 2021, 6:48 a.m. | #1
On Tue, Apr 27, 2021 at 10:30:46AM +0200, Hannes Reinecke wrote:
> +/*

> + *  Original linux SCSI Status codes. They are shifted 1 bit right

> + *  from those found in the SCSI standards.

> + */

> +

> +#define GOOD                 0x00

> +#define CHECK_CONDITION      0x01

> +#define CONDITION_GOOD       0x02

> +#define BUSY                 0x04

> +#define INTERMEDIATE_GOOD    0x08

> +#define INTERMEDIATE_C_GOOD  0x0a

> +#define RESERVATION_CONFLICT 0x0c

> +#define COMMAND_TERMINATED   0x11

> +#define QUEUE_FULL           0x14

> +#define ACA_ACTIVE           0x18

> +#define TASK_ABORTED         0x20


I don't think there is any need to keep defining them, is there?
Hannes Reinecke April 29, 2021, 7:29 a.m. | #2
On 4/29/21 8:48 AM, Christoph Hellwig wrote:
> On Tue, Apr 27, 2021 at 10:30:46AM +0200, Hannes Reinecke wrote:

>> +/*

>> + *  Original linux SCSI Status codes. They are shifted 1 bit right

>> + *  from those found in the SCSI standards.

>> + */

>> +

>> +#define GOOD                 0x00

>> +#define CHECK_CONDITION      0x01

>> +#define CONDITION_GOOD       0x02

>> +#define BUSY                 0x04

>> +#define INTERMEDIATE_GOOD    0x08

>> +#define INTERMEDIATE_C_GOOD  0x0a

>> +#define RESERVATION_CONFLICT 0x0c

>> +#define COMMAND_TERMINATED   0x11

>> +#define QUEUE_FULL           0x14

>> +#define ACA_ACTIVE           0x18

>> +#define TASK_ABORTED         0x20

> 

> I don't think there is any need to keep defining them, is there?

> 

Probably not. I'll drop them for the next round.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		           Kernel Storage Architect
hare@suse.de			                  +49 911 74053 688
SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), GF: Felix Imendörffer
Douglas Gilbert April 29, 2021, 3:52 p.m. | #3
On 2021-04-29 2:48 a.m., Christoph Hellwig wrote:
> On Tue, Apr 27, 2021 at 10:30:46AM +0200, Hannes Reinecke wrote:

>> +/*

>> + *  Original linux SCSI Status codes. They are shifted 1 bit right

>> + *  from those found in the SCSI standards.

>> + */

>> +

>> +#define GOOD                 0x00

>> +#define CHECK_CONDITION      0x01

>> +#define CONDITION_GOOD       0x02

>> +#define BUSY                 0x04

>> +#define INTERMEDIATE_GOOD    0x08

>> +#define INTERMEDIATE_C_GOOD  0x0a

>> +#define RESERVATION_CONFLICT 0x0c

>> +#define COMMAND_TERMINATED   0x11

>> +#define QUEUE_FULL           0x14

>> +#define ACA_ACTIVE           0x18

>> +#define TASK_ABORTED         0x20

> 

> I don't think there is any need to keep defining them, is there?


If you don't mind breaking existing, user space facing APIs, then
yes, they can be dropped ...

Banishing them to the sg header is correct IMO. Which is exactly
what this patch does.

One thought, they could be wrapped with:

#ifndef __KERNEL__
...
#endif

and repeated in a new header: scsi/sg_priv.h
Then the sg driver and any other files that need those old defines
could include sg_priv.h . The result would be parts of the kernel
not being polluted with commonly use names like GOOD and BUSY.


Anyway:

Reviewed-by: Douglas Gilbert <dgilbert@interlog.com>