Re: [PATCH 06/36] target: Return Function Complete

Dmitry Bogdanov
2022-07-11T10:46:51Z

On Fri, Jul 08, 2022 at 11:51:38PM +0000, Thinh Nguyen wrote:
>
> On 7/7/2022, Dmitry Bogdanov wrote:
> > Hi Thinh,
> >
> > On Wed, Jul 06, 2022 at 04:35:01PM -0700, Thinh Nguyen wrote:
> >> According to SAM-4 r14 section 7.2, for ABORT TASK function, a response
> >> of FUNCTION COMPLETE shall indicate that the command was aborted or was
> >> not in the task set. Currently we respond with TASK DOES NOT EXIST when
> >> there's no command in the task set. Fix the response to FUNCTION
> >> COMPLETE instead.
> > SAM does not describe a response status encoding. But other specs
> > do describe. For example, iSCSI RFC7143 11.6.1. Response
> > 0 - Function complete
> > 1 - Task does not exist
> > The mapping of the response code into a SCSI service response code
> > value, if needed, is outside the scope of this document. However, in
> > symbolic terms, Response values 0 and 1 map to the SCSI service
> > response of FUNCTION COMPLETE.
> >
> > So, the current code is according to specs.
> > Moreover, TMR_TASK_DOES_NOT_EXIST is used in several fabric drivers to
> > handle some corner cases.
>
> Ok, it's a bit confusing. So, the SCSI service response needs to reflect
> FUNCTION COMPLETE, but the FUNCTION COMPLETE can be different for other
> specs?
Yes, SCSI service response code may have a different values to differentiate
a level of "success" :) or a reason of failure.
>
> Thanks,
> Thinh
>
> >> Fixes: 3d28934aaae5 ("target: Add TMR_ABORT_TASK task management support")
> >> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> >> ---
> >> drivers/target/target_core_tmr.c | 4 ++--
> >> 1 file changed, 2 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c
> >> index 2af80d0998bf..724ddabda488 100644
> >> --- a/drivers/target/target_core_tmr.c
> >> +++ b/drivers/target/target_core_tmr.c
> >> @@ -170,9 +170,9 @@ void core_tmr_abort_task(
> >> if (dev->transport->tmr_notify)
> >> dev->transport->tmr_notify(dev, TMR_ABORT_TASK, &aborted_list);
> >>
> >> - printk("ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST for ref_tag: %lld\n",
> >> + printk("ABORT_TASK: Sending TMR_FUNCTION_COMPLETE for ref_tag: %lld\n",
> >> tmr->ref_task_tag);
> >> - tmr->response = TMR_TASK_DOES_NOT_EXIST;
> >> + tmr->response = TMR_FUNCTION_COMPLETE;
> >> atomic_long_inc(&dev->aborts_no_task);
> >> }
> >>
>