Re: [PATCH 17/24] snic: reserve tag for TMF

John Garry
2022-05-06T13:28:19Z

>
> diff --git a/drivers/scsi/snic/snic_main.c b/drivers/scsi/snic/snic_main.c
> index 29d56396058c..f344cbc27923 100644
> --- a/drivers/scsi/snic/snic_main.c
> +++ b/drivers/scsi/snic/snic_main.c
> @@ -512,6 +512,9 @@ snic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> max_t(u32, SNIC_MIN_IO_REQ, max_ios));
>
> snic->max_tag_id = shost->can_queue;
> + /* Reserve one reset command */
> + shost->can_queue--;
> + snic->tmf_tag_id = shost->can_queue;
>
> shost->max_lun = snic->config.luns_per_tgt;
> shost->max_id = SNIC_MAX_TARGET;
> diff --git a/drivers/scsi/snic/snic_scsi.c b/drivers/scsi/snic/snic_scsi.c
> index 5f17666f3e1d..e18c8c5e4b46 100644
> --- a/drivers/scsi/snic/snic_scsi.c
> +++ b/drivers/scsi/snic/snic_scsi.c
> @@ -1018,17 +1018,6 @@ snic_hba_reset_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
> "reset_cmpl: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x, ctx = %lx\n",
> typ, hdr_stat, cmnd_id, hid, ctx);
>
> - /* spl case, host reset issued through ioctl */
> - if (cmnd_id == SCSI_NO_TAG) {
> - rqi = (struct snic_req_info *) ctx;
> - SNIC_HOST_INFO(snic->shost,
> - "reset_cmpl:Tag %d ctx %lx cmpl stat %s\n",
> - cmnd_id, ctx, snic_io_status_to_str(hdr_stat));
> - sc = rqi->sc;
> -
> - goto ioctl_hba_rst;
> - }
> -
> if (cmnd_id >= snic->max_tag_id) {
> SNIC_HOST_ERR(snic->shost,
> "reset_cmpl: Tag 0x%x out of Range,HdrStat %s\n",
> @@ -1039,7 +1028,6 @@ snic_hba_reset_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
> }
>
> sc = scsi_host_find_tag(snic->shost, cmnd_id);
> -ioctl_hba_rst:
> if (!sc) {
> atomic64_inc(&snic->s_stats.io.sc_null);
> SNIC_HOST_ERR(snic->shost,
> @@ -1725,7 +1713,7 @@ snic_dr_clean_single_req(struct snic *snic,
> {
> struct snic_req_info *rqi = NULL;
> struct snic_tgt *tgt = NULL;
> - struct scsi_cmnd *sc = NULL;
> + struct scsi_cmnd *sc;
> spinlock_t *io_lock = NULL;
> u32 sv_state = 0, tmf = 0;
> DECLARE_COMPLETION_ONSTACK(tm_done);
> @@ -2238,13 +2226,6 @@ snic_issue_hba_reset(struct snic *snic, struct scsi_cmnd *sc)
> goto hba_rst_end;
> }
>
> - if (snic_cmd_tag(sc) == SCSI_NO_TAG) {
> - memset(scsi_cmd_priv(sc), 0,
> - sizeof(struct snic_internal_io_state));
> - SNIC_HOST_INFO(snic->shost, "issu_hr:Host reset thru ioctl.\n");
> - rqi->sc = sc;
> - }
> -
> req = rqi_to_req(rqi);
>
> io_lock = snic_io_lock_hash(snic, sc);
> @@ -2319,11 +2300,13 @@ snic_issue_hba_reset(struct snic *snic, struct scsi_cmnd *sc)
> } /* end of snic_issue_hba_reset */
>
> int
> -snic_reset(struct Scsi_Host *shost, struct scsi_cmnd *sc)
> +snic_reset(struct Scsi_Host *shost)
> {
> struct snic *snic = shost_priv(shost);
> + struct scsi_cmnd *sc = NULL;
> enum snic_state sv_state;
> unsigned long flags;
> + u32 start_time = jiffies;
> int ret = FAILED;
>
> /* Set snic state as SNIC_FWRESET*/
> @@ -2348,6 +2331,18 @@ snic_reset(struct Scsi_Host *shost, struct scsi_cmnd *sc)
> while (atomic_read(&snic->ios_inflight))
> schedule_timeout(msecs_to_jiffies(1));
>
> + sc = scsi_host_find_tag(shost, snic->tmf_tag_id);

Maybe I am missing something but this does not seem right. As I see,
blk-mq has driver tags in range [0, snic->tmf_tag_id - 1], so we cannot
call scsi_host_find_tag() -> blk_mq_unique_tag_to_tag(snic->tmf_tag_id)

thanks,
John