Re: [PATCH v2 24/35] scsi: hp_sw: Have scsi-ml retry scsi_exec_req errors

[Martin Wilck <mwilck@suse.com>]

On Wed, 2022-09-28 at 21:53 -0500, Mike Christie wrote:
> This has hp_sw have scsi-ml retry scsi_exec_req errors instead of
> driving
> them itself.
> 
> Signed-off-by: Mike Christie <michael.christie@oracle.com>
> ---
>  drivers/scsi/device_handler/scsi_dh_hp_sw.c | 58 +++++++++++++------
> --
>  1 file changed, 35 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/scsi/device_handler/scsi_dh_hp_sw.c
> b/drivers/scsi/device_handler/scsi_dh_hp_sw.c
> index adcbe3b883b7..c186809f2e17 100644
> --- a/drivers/scsi/device_handler/scsi_dh_hp_sw.c
> +++ b/drivers/scsi/device_handler/scsi_dh_hp_sw.c
> @@ -46,9 +46,6 @@ static int tur_done(struct scsi_device *sdev,
> struct hp_sw_dh_data *h,
>         int ret = SCSI_DH_IO;
>  
>         switch (sshdr->sense_key) {
> -       case UNIT_ATTENTION:
> -               ret = SCSI_DH_IMM_RETRY;
> -               break;
>         case NOT_READY:
>                 if (sshdr->asc == 0x04 && sshdr->ascq == 2) {
>                         /*
> @@ -85,8 +82,17 @@ static int hp_sw_tur(struct scsi_device *sdev,
> struct hp_sw_dh_data *h)
>         int ret = SCSI_DH_OK, res;
>         blk_opf_t req_flags = REQ_FAILFAST_DEV |
> REQ_FAILFAST_TRANSPORT |
>                 REQ_FAILFAST_DRIVER;
> +       struct scsi_failure failures[] = {
> +               {
> +                       .sense = UNIT_ATTENTION,
> +                       .asc = SCMD_FAILURE_ASC_ANY,
> +                       .ascq = SCMD_FAILURE_ASCQ_ANY,
> +                       .allowed = SCMD_FAILURE_NO_LIMIT,
> +                       .result = SAM_STAT_CHECK_CONDITION,
> +               },
> +               {},
> +       };
>  
> -retry:
>         res = scsi_exec_req(((struct scsi_exec_args) {
>                                 .sdev = sdev,
>                                 .cmd = cmd,
> @@ -94,7 +100,8 @@ static int hp_sw_tur(struct scsi_device *sdev,
> struct hp_sw_dh_data *h)
>                                 .sshdr = &sshdr,
>                                 .timeout = HP_SW_TIMEOUT,
>                                 .retries = HP_SW_RETRIES,
> -                               .op_flags = req_flags }));
> +                               .op_flags = req_flags,
> +                               .failures = failures }));
>         if (res) {
>                 if (scsi_sense_valid(&sshdr))
>                         ret = tur_done(sdev, h, &sshdr);
> @@ -108,8 +115,6 @@ static int hp_sw_tur(struct scsi_device *sdev,
> struct hp_sw_dh_data *h)
>                 h->path_state = HP_SW_PATH_ACTIVE;
>                 ret = SCSI_DH_OK;
>         }
> -       if (ret == SCSI_DH_IMM_RETRY)
> -               goto retry;
>  
>         return ret;
>  }
> @@ -126,19 +131,33 @@ static int hp_sw_start_stop(struct
> hp_sw_dh_data *h)
>         struct scsi_sense_hdr sshdr;
>         struct scsi_device *sdev = h->sdev;
>         int res, rc = SCSI_DH_OK;
> -       int retry_cnt = HP_SW_RETRIES;
>         blk_opf_t req_flags = REQ_FAILFAST_DEV |
> REQ_FAILFAST_TRANSPORT |
>                 REQ_FAILFAST_DRIVER;
> +       struct scsi_failure failures[] = {
> +               {
> +                       /*
> +                        * LUN not ready - manual intervention
> required
> +                        *
> +                        * Switch-over in progress, retry.
> +                        */
> +                       .sense = NOT_READY,
> +                       .asc = 0x04,
> +                       .ascq = 0x03,
> +                       .allowed = HP_SW_RETRIES,
> +                       .result = SAM_STAT_CHECK_CONDITION,
> +               },
> +               {},
> +       };
>  
> -retry:
>         res = scsi_exec_req(((struct scsi_exec_args) {
> -                               .sdev = sdev,
> -                               .cmd = cmd,
> -                               .data_dir = DMA_NONE,
> -                               .sshdr = &sshdr,
> -                               .timeout = HP_SW_TIMEOUT,
> -                               .retries = HP_SW_RETRIES,
> -                               .op_flags = req_flags }));
> +                                       .sdev = sdev,
> +                                       .cmd = cmd,
> +                                       .data_dir = DMA_NONE,
> +                                       .sshdr = &sshdr,
> +                                       .timeout = HP_SW_TIMEOUT,
> +                                       .retries = HP_SW_RETRIES,
> +                                       .op_flags = req_flags,
> +                                       .failures = failures }));

Nitpick: this looks as if you hadn't got the indentation right in
08/35.

Martin