linux-toradex.git/drivers/target/target_core_spc.c, branch v3.10.78

target: Drop arbitrary maximum I/O size limit

2015-02-06T06:35:41+00:00

commit 046ba64285a4389ae5e9a7dfa253c6bff3d7c341 upstream.

This patch drops the arbitrary maximum I/O size limit in sbc_parse_cdb(),
which currently for fabric_max_sectors is hardcoded to 8192 (4 MB for 512
byte sector devices), and for hw_max_sectors is a backend driver dependent
value.

This limit is problematic because Linux initiators have only recently
started to honor block limits MAXIMUM TRANSFER LENGTH, and other non-Linux
based initiators (eg: MSFT Fibre Channel) can also generate I/Os larger
than 4 MB in size.

Currently when this happens, the following message will appear on the
target resulting in I/Os being returned with non recoverable status:

  SCSI OP 28h with too big sectors 16384 exceeds fabric_max_sectors: 8192

Instead, drop both [fabric,hw]_max_sector checks in sbc_parse_cdb(),
and convert the existing hw_max_sectors into a purely informational
attribute used to represent the granuality that backend driver and/or
subsystem code is splitting I/Os upon.

Also, update FILEIO with an explicit FD_MAX_BYTES check in fd_execute_rw()
to deal with the one special iovec limitiation case.

v2 changes:
  - Drop hw_max_sectors check in sbc_parse_cdb()

Reported-by: Lance Gropper 
Reported-by: Stefan Priebe 
Cc: Christoph Hellwig 
Cc: Martin K. Petersen 
Cc: Roland Dreier 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Report correct response length for some commands

2014-07-01T03:09:45+00:00

commit 2426bd456a61407388b6e61fc5f98dbcbebc50e2 upstream.

When an initiator sends an allocation length bigger than what its
command consumes, the target should only return the actual response data
and set the residual length to the unused part of the allocation length.

Add a helper function that command handlers (INQUIRY, READ CAPACITY,
etc) can use to do this correctly, and use this code to get the correct
residual for commands that don't use the full initiator allocation in the
handlers for READ CAPACITY, READ CAPACITY(16), INQUIRY, MODE SENSE and
REPORT LUNS.

This addresses a handful of failures as reported by Christophe with
the Windows Certification Kit:

  http://permalink.gmane.org/gmane.linux.scsi.target.devel/6515

Signed-off-by: Roland Dreier 
Tested-by: Christophe Vu-Brugier 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix trailing ASCII space usage in INQUIRY vendor+model

2013-09-08T05:09:59+00:00

commit ee60bddba5a5f23e39598195d944aa0eb2d455e5 upstream.

This patch fixes spc_emulate_inquiry_std() to add trailing ASCII
spaces for INQUIRY vendor + model fields following SPC-4 text:

  "ASCII data fields described as being left-aligned shall have any
   unused bytes at the end of the field (i.e., highest offset) and
   the unused bytes shall be filled with ASCII space characters (20h)."

This addresses a problem with Falconstor NSS multipathing.

Reported-by: Tomas Molota 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix parameter list length checking in MODE SELECT

2013-02-13T20:16:11+00:00

An empty parameter list (length == 0) is not an error, so succeed MODE
SELECT in this case.  If the parameter list length is too small,
return the correct sense code of PARAMETER LIST LENGTH ERROR.

Signed-off-by: Roland Dreier 
Signed-off-by: Nicholas Bellinger

target/iblock: Use backend REQ_FLUSH hint for WriteCacheEnabled status

2013-02-13T19:27:51+00:00

This patch allows IBLOCK to check block hints in request_queue->flush_flags
when reporting current backend device WriteCacheEnabled status to a remote
SCSI initiator port.

This is done via a se_subsystem_api->get_write_cache() call instead of a
backend se_device creation time flag, as we expect REQ_FLUSH bits to possibly
change from an underlying blk_queue_flush() by the SCSI disk driver, or
internal raw struct block_device driver usage.

Also go ahead and update iblock_execute_rw() bio I/O path code to use
REQ_FLUSH + REQ_FUA hints when determining WRITE_FUA usage, and make SPC
emulation code use a spc_check_dev_wce() helper to handle both types of
cases for virtual backend subsystem drivers.

(asias: Drop unnecessary comparsion operators)

Reported-by: majianpeng 
Cc: majianpeng 
Cc: Christoph Hellwig 
Cc: Jens Axboe 
Cc: James Bottomley 
Signed-off-by: Nicholas Bellinger

target: Export SPC inquiry emulation

2013-02-13T19:27:22+00:00

Some target drivers might need to access the inquiry data
directly, without sending out the actual command.
So export these functions.

Signed-off-by: Hannes Reinecke 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger

target: Fix zero-length MODE_SENSE regression

2013-01-29T22:24:20+00:00

This patch fixes a regression introduced in v3.8-rc1 code where
a zero-length MODE_SENSE was no longer returning GOOD status, but
instead returning TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE to generate
a CHECK_CONDITION status.

This regression was introduced with the following commit:

  commit de103c93aff0bed0ae984274e5dc8b95899badab
  Author: Christoph Hellwig 
  Date:   Tue Nov 6 12:24:09 2012 -0800

      target: pass sense_reason as a return value

and this patch has been tested with the following zero-length CDB:

  sg_raw /dev/sdd 5a 00 0a 00 00 00 00 00 00 00
  SCSI Status: Good

  Sense Information:
  sense buffer empty

Cc: Christoph Hellwig 
Cc: Paolo Bonzini 
Cc: Roland Dreier 
Signed-off-by: Nicholas Bellinger

target: Fix zero-length INQUIRY additional sense code regression

2013-01-29T22:22:01+00:00

This patch fixes a minor regression introduced in v3.8-rc1 code
where a zero-length INQUIRY was no longer returning the correct
INVALID FIELD IN CDB additional sense code.

This regression was introduced with the following commit:

  commit de103c93aff0bed0ae984274e5dc8b95899badab
  Author: Christoph Hellwig 
  Date:   Tue Nov 6 12:24:09 2012 -0800

      target: pass sense_reason as a return value

and this patch has been tested with the following zero-length CDB:

  sg_raw /dev/sdd 12 00 83 00 00 00
  SCSI Status: Check Condition

  Sense Information:
   Fixed format, current;  Sense key: Illegal Request
   Additional sense: Invalid field in cdb

Cc: Christoph Hellwig 
Cc: Paolo Bonzini 
Cc: Roland Dreier 
Signed-off-by: Nicholas Bellinger

2012-11-28T06:47:02+00:00

v2: Use correct target_core_stat.c 2006 copyright year
v3: Drop extra unnessary legal verbage from header (hch)

Cc: Christoph Hellwig 
Signed-off-by: Nicholas Bellinger

target: Add/check max_write_same_len device attribute + update block limits VPD

2012-11-15T20:27:21+00:00

This patch adds a new max_write_same_len device attribute for use with
WRITE_SAME w/ UNMAP=0 backend emulation.  This can be useful for
lowering the default backend value (IBLOCK uses 0xFFFF).

Also, update block limits VPD emulation code in spc_emulate_evpd_b0() to
report MAXIMUM WRITE SAME LENGTH, and enforce max_write_same_len during
sbc_parse() -> sbc_setup_write_same() CDB sanity checking for all emulated
WRITE_SAME w/ UNMAP=0 cases.

(Robert: Move max_write_same_len check in sbc_setup_write_same() to
         check both WRITE_SAME w/ UNMAP=1 and w/ UNMAP=0 cases)

Cc: Christoph Hellwig 
Cc: Martin K. Petersen 
Cc: Robert Elliott 
Signed-off-by: Nicholas Bellinger