linux-toradex.git/include/target/target_core_backend.h, branch v5.18

scsi: target: Allows backend drivers to fail with specific sense codes

2021-08-18T02:28:40+00:00

Currently, backend drivers can fail I/O with SAM_STAT_CHECK_CONDITION which
gets us TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE.

Add a new helper that allows backend drivers to fail with specific sense
codes.

This is based on a patch from Mike Christie .

Cc: Mike Christie 
Link: https://lore.kernel.org/r/20210803145410.80147-2-s.samoylenko@yadro.com
Reviewed-by: David Disseldorp 
Signed-off-by: Sergey Samoylenko 
Signed-off-by: Martin K. Petersen

scsi: target: core: Fix backend plugging

2021-03-04T22:37:02+00:00

target_core_iblock is plugging and unplugging on every command and this is
causing perf issues for drivers that prefer batched cmds. With recent
patches we can now take multiple cmds from a fabric driver queue and then
pass them down the backend drivers in a batch. This patch adds this support
by adding 2 callouts to the backend for plugging and unplugging the
device. Subsequent commits will add support for iblock and tcmu device
plugging.

Link: https://lore.kernel.org/r/20210227170006.5077-22-michael.christie@oracle.com
Reviewed-by: Bodo Stroesser 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen

scsi: target: core: Add cmd length set before cmd complete

2021-02-23T03:21:29+00:00

TCM doesn't properly handle underflow case for service actions. One way to
prevent it is to always complete command with
target_complete_cmd_with_length(), however it requires access to data_sg,
which is not always available.

This change introduces target_set_cmd_data_length() function which allows
to set command data length before completing it.

Link: https://lore.kernel.org/r/20210209072202.41154-2-a.miloserdov@yadro.com
Reviewed-by: Roman Bolshakov 
Reviewed-by: Bodo Stroesser 
Signed-off-by: Aleksandr Miloserdov 
Signed-off-by: Martin K. Petersen

scsi: target: Add tmr_notify backend function

2020-07-29T02:25:26+00:00

Target core is modified to call an optional backend callback function if a
TMR is received or commands are aborted implicitly after a PR command was
received.  The backend function takes as parameters the se_dev, the type of
the TMR, and the list of aborted commands.  If no commands were aborted, an
empty list is supplied.

Link: https://lore.kernel.org/r/20200726153510.13077-3-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie 
Signed-off-by: Bodo Stroesser 
Signed-off-by: Martin K. Petersen

scsi: target: tcmu: Make pgr_support and alua_support attributes writable

2020-05-08T02:39:22+00:00

Currently in tcmu reservation commands are handled by core's pr
implementation (default) or completely rejected (emulate_pr set to 0). We
additionally want to be able to do full reservation handling in
userspace. Therefore we need a way to set TRANSPORT_FLAG_PASSTHROUGH_PGR.

The inverted flag is displayed by attribute pgr_support.  Since we moved
the flag from transport/backend to se_device in the previous commit, we now
can make it changeable per device by allowing to write the attribute.  The
new field transport_flags_changeable in transport/backend is used to reject
writing if not allowed for a backend.

Regarding ALUA we also want to be able to passthrough commands to userspace
in tcmu. Therefore we need TRANSPORT_FLAG_PASSTHROUGH_ALUA to be
changeable, because by setting it we can switch off all ALUA checks in
core. So we also set TRANSPORT_FLAG_PASSTHROUGH_ALUA in tcmu's
transport_flags_changeable.

Of course, ALUA and reservation handling in userspace will work only, if
session/nexus information is sent to userspace along with every
command. This will be object of a patch series announced by Mike Christie.

Link: https://lore.kernel.org/r/20200427150823.15350-5-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie 
Signed-off-by: Bodo Stroesser 
Signed-off-by: Martin K. Petersen

scsi: target: Make transport_flags per device

2020-05-08T02:39:21+00:00

pgr_support and alua_support device attributes show the inverted value of
the transport_flags:

 * TRANSPORT_FLAG_PASSTHROUGH_PGR
 * TRANSPORT_FLAG_PASSTHROUGH_ALUA

These attributes are per device, while the flags are per backend. Rename
the transport_flags in backend/transport to transport_flags_default and use
this value to initialize the new transport_flags field in the se_device
structure.

Now data and attribute both are per se_device.

Link: https://lore.kernel.org/r/20200427150823.15350-4-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie 
Signed-off-by: Bodo Stroesser 
Signed-off-by: Martin K. Petersen

scsi: target: tcmu: Add attributes enforce_pr_isids and force_pr_aptpl

2020-05-08T02:39:18+00:00

tcmu has not set TRANSPORT_FLAG_PASSTHROUGH_PGR. Therefore the in-core pr
emulation is active by default, but there are some attributes for
configuration missing. Add them.

Link: https://lore.kernel.org/r/20200427150823.15350-3-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie 
Signed-off-by: Bodo Stroesser 
Signed-off-by: Martin K. Petersen

scsi: treewide: Consolidate {get,put}_unaligned_[bl]e24() definitions

2020-03-17T02:08:34+00:00

Move the get_unaligned_be24(), get_unaligned_le24() and
put_unaligned_le24() definitions from various drivers into
include/linux/unaligned/generic.h. Add a put_unaligned_be24()
implementation.

Link: https://lore.kernel.org/r/20200313203102.16613-4-bvanassche@acm.org
Cc: Keith Busch 
Cc: Sagi Grimberg 
Cc: Jens Axboe 
Cc: Harvey Harrison 
Cc: Martin K. Petersen 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: H. Peter Anvin 
Cc: Andrew Morton 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Andy Shevchenko 
Reviewed-by: Greg Kroah-Hartman  # For drivers/usb
Reviewed-by: Felipe Balbi  # For drivers/usb/gadget
Signed-off-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

scsi: target: add helper to check if dev is configured

2018-07-31T03:17:53+00:00

This just adds a helper function to check if a device is configured and it
converts the target users to use it. The next patch will add a backend
module user so those types of modules do not have to know the lio core
details.

Signed-off-by: Mike Christie 
Reviewed-by: Xiubo Li 
Signed-off-by: Martin K. Petersen

scsi: target: remove target_find_device

2018-06-26T16:27:06+00:00

target_find_device is no longer used, so remove it.

Signed-off-by: Mike Christie 
Tested-by: Xiubo Li 
Signed-off-by: Martin K. Petersen