Re: [PATCH V2] mpt3sas: support target smid for [abort|query] task

[Sreekanth Reddy <sreekanth.reddy@broadcom.com>]

On Sun, Jul 14, 2019 at 9:14 AM Minwoo Im <minwoo.im@samsung.com> wrote:
>
> We can request task management IOCTL command(MPI2_FUNCTION_SCSI_TASK_MGMT)
> to /dev/mpt3ctl.  If the given task_type is either abort task or query
> task, it may need a field named "Initiator Port Transfer Tag to Manage"
> in the IU.
>
> Current code does not support to check target IPTT tag from the
> tm_request.  This patch introduces to check TaskMID given from the
> userspace as a target tag.  We have a rule of relationship between
> (struct request *req->tag) and smid in mpt3sas_base.c:
>
> 3318 u16
> 3319 mpt3sas_base_get_smid_scsiio(struct MPT3SAS_ADAPTER *ioc, u8 cb_idx,
> 3320         struct scsi_cmnd *scmd)
> 3321 {
> 3322         struct scsiio_tracker *request = scsi_cmd_priv(scmd);
> 3323         unsigned int tag = scmd->request->tag;
> 3324         u16 smid;
> 3325
> 3326         smid = tag + 1;
>
> So if we want to abort a request tagged #X, then we can pass (X + 1) to
> this IOCTL handler.  Otherwise, user space just can pass 0 TaskMID to
> abort the first outstanding smid which is legacy behaviour.
>
> Cc: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> Cc: Suganath Prabu Subramani <suganath-prabu.subramani@broadcom.com>
> Cc: Sathya Prakash <sathya.prakash@broadcom.com>
> Cc: James E.J. Bottomley <jejb@linux.ibm.com>
> Cc: Martin K. Petersen <martin.petersen@oracle.com>
> Cc: MPT-FusionLinux.pdl@broadcom.com
> Signed-off-by: Minwoo Im <minwoo.im@samsung.com>

Acked-by:  Sreekanth Reddy <sreekanth.reddy@broadcom.com>

> ---
>  drivers/scsi/mpt3sas/mpt3sas_ctl.c | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> index b2bb47c14d35..f6b8fd90610a 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> @@ -596,8 +596,16 @@ _ctl_set_task_mid(struct MPT3SAS_ADAPTER *ioc, struct mpt3_ioctl_command *karg,
>                 if (priv_data->sas_target->handle != handle)
>                         continue;
>                 st = scsi_cmd_priv(scmd);
> -               tm_request->TaskMID = cpu_to_le16(st->smid);
> -               found = 1;
> +
> +               /*
> +                * If the given TaskMID from the user space is zero, then the
> +                * first outstanding smid will be picked up.  Otherwise,
> +                * targeted smid will be the one.
> +                */
> +               if (!tm_request->TaskMID || tm_request->TaskMID == st->smid) {
> +                       tm_request->TaskMID = cpu_to_le16(st->smid);
> +                       found = 1;
> +               }
>         }
>
>         if (!found) {
> --
> 2.16.1
>