[SCSI] ibmvfc: Add ADISC support

Add an ADISC to the target discovery job in order to sanity check whether or
not we need to re-login to the target.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 135 insertions, 0 deletions

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 1917acb9102e..a33fa133f75b 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -2914,6 +2914,139 @@ static void ibmvfc_tgt_implicit_logout(struct ibmvfc_target *tgt)
 }
 
 /**
+ * ibmvfc_adisc_needs_plogi - Does device need PLOGI?
+ * @mad:        ibmvfc passthru mad struct
+ * @tgt:        ibmvfc target struct
+ *
+ * Returns:
+ *      1 if PLOGI needed / 0 if PLOGI not needed
+ **/
+static int ibmvfc_adisc_needs_plogi(struct ibmvfc_passthru_mad *mad,
+                                    struct ibmvfc_target *tgt)
+{
+        if (memcmp(&mad->fc_iu.response[2], &tgt->ids.port_name,
+                   sizeof(tgt->ids.port_name)))
+                return 1;
+        if (memcmp(&mad->fc_iu.response[4], &tgt->ids.node_name,
+                   sizeof(tgt->ids.node_name)))
+                return 1;
+        if (mad->fc_iu.response[6] != tgt->scsi_id)
+                return 1;
+        return 0;
+}
+
+/**
+ * ibmvfc_tgt_adisc_done - Completion handler for ADISC
+ * @evt:        ibmvfc event struct
+ *
+ **/
+static void ibmvfc_tgt_adisc_done(struct ibmvfc_event *evt)
+{
+        struct ibmvfc_target *tgt = evt->tgt;
+        struct ibmvfc_host *vhost = evt->vhost;
+        struct ibmvfc_passthru_mad *mad = &evt->xfer_iu->passthru;
+        u32 status = mad->common.status;
+        u8 fc_reason, fc_explain;
+
+        vhost->discovery_threads--;
+        ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_NONE);
+
+        switch (status) {
+        case IBMVFC_MAD_SUCCESS:
+                tgt_dbg(tgt, "ADISC succeeded\n");
+                if (ibmvfc_adisc_needs_plogi(mad, tgt))
+                        tgt->need_login = 1;
+                break;
+        case IBMVFC_MAD_DRIVER_FAILED:
+                break;
+        case IBMVFC_MAD_FAILED:
+        default:
+                tgt->need_login = 1;
+                fc_reason = (mad->fc_iu.response[1] & 0x00ff0000) >> 16;
+                fc_explain = (mad->fc_iu.response[1] & 0x0000ff00) >> 8;
+                tgt_info(tgt, "ADISC failed: %s (%x:%x) %s (%x) %s (%x) rc=0x%02X\n",
+                         ibmvfc_get_cmd_error(mad->iu.status, mad->iu.error),
+                         mad->iu.status, mad->iu.error,
+                         ibmvfc_get_fc_type(fc_reason), fc_reason,
+                         ibmvfc_get_ls_explain(fc_explain), fc_explain, status);
+                break;
+        };
+
+        kref_put(&tgt->kref, ibmvfc_release_tgt);
+        ibmvfc_free_event(evt);
+        wake_up(&vhost->work_wait_q);
+}
+
+/**
+ * ibmvfc_init_passthru - Initialize an event struct for FC passthru
+ * @evt:                ibmvfc event struct
+ *
+ **/
+static void ibmvfc_init_passthru(struct ibmvfc_event *evt)
+{
+        struct ibmvfc_passthru_mad *mad = &evt->iu.passthru;
+
+        memset(mad, 0, sizeof(*mad));
+        mad->common.version = 1;
+        mad->common.opcode = IBMVFC_PASSTHRU;
+        mad->common.length = sizeof(*mad) - sizeof(mad->fc_iu) - sizeof(mad->iu);
+        mad->cmd_ioba.va = (u64)evt->crq.ioba +
+                offsetof(struct ibmvfc_passthru_mad, iu);
+        mad->cmd_ioba.len = sizeof(mad->iu);
+        mad->iu.cmd_len = sizeof(mad->fc_iu.payload);
+        mad->iu.rsp_len = sizeof(mad->fc_iu.response);
+        mad->iu.cmd.va = (u64)evt->crq.ioba +
+                offsetof(struct ibmvfc_passthru_mad, fc_iu) +
+                offsetof(struct ibmvfc_passthru_fc_iu, payload);
+        mad->iu.cmd.len = sizeof(mad->fc_iu.payload);
+        mad->iu.rsp.va = (u64)evt->crq.ioba +
+                offsetof(struct ibmvfc_passthru_mad, fc_iu) +
+                offsetof(struct ibmvfc_passthru_fc_iu, response);
+        mad->iu.rsp.len = sizeof(mad->fc_iu.response);
+}
+
+/**
+ * ibmvfc_tgt_adisc - Initiate an ADISC for specified target
+ * @tgt:                ibmvfc target struct
+ *
+ **/
+static void ibmvfc_tgt_adisc(struct ibmvfc_target *tgt)
+{
+        struct ibmvfc_passthru_mad *mad;
+        struct ibmvfc_host *vhost = tgt->vhost;
+        struct ibmvfc_event *evt;
+
+        if (vhost->discovery_threads >= disc_threads)
+                return;
+
+        kref_get(&tgt->kref);
+        evt = ibmvfc_get_event(vhost);
+        vhost->discovery_threads++;
+        ibmvfc_init_event(evt, ibmvfc_tgt_adisc_done, IBMVFC_MAD_FORMAT);
+        evt->tgt = tgt;
+
+        ibmvfc_init_passthru(evt);
+        mad = &evt->iu.passthru;
+        mad->iu.flags = IBMVFC_FC_ELS;
+        mad->iu.scsi_id = tgt->scsi_id;
+
+        mad->fc_iu.payload[0] = IBMVFC_ADISC;
+        memcpy(&mad->fc_iu.payload[2], &vhost->login_buf->resp.port_name,
+               sizeof(vhost->login_buf->resp.port_name));
+        memcpy(&mad->fc_iu.payload[4], &vhost->login_buf->resp.node_name,
+               sizeof(vhost->login_buf->resp.node_name));
+        mad->fc_iu.payload[6] = vhost->login_buf->resp.scsi_id & 0x00ffffff;
+
+        ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_INIT_WAIT);
+        if (ibmvfc_send_event(evt, vhost, default_timeout)) {
+                vhost->discovery_threads--;
+                ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_NONE);
+                kref_put(&tgt->kref, ibmvfc_release_tgt);
+        } else
+                tgt_dbg(tgt, "Sent ADISC\n");
+}
+
+/**
  * ibmvfc_tgt_query_target_done - Completion handler for Query Target MAD
  * @evt:        ibmvfc event struct
  *
@@ -2933,6 +3066,8 @@ static void ibmvfc_tgt_query_target_done(struct ibmvfc_event *evt)
                 tgt->new_scsi_id = rsp->scsi_id;
                 if (rsp->scsi_id != tgt->scsi_id)
                         ibmvfc_init_tgt(tgt, ibmvfc_tgt_implicit_logout);
+                else
+                        ibmvfc_init_tgt(tgt, ibmvfc_tgt_adisc);
                 break;
         case IBMVFC_MAD_DRIVER_FAILED:
                 break;