lpfc: Fix host reset escalation killing all IOs.

Fix host reset escalation killing all IOs.

SLI-3 adapters will use a new host template. The template differs
from SLI-4 adapters in that it does not have an eh_host_reset_handler.

Lpfc has traditionally never had a host_reset. The host reset
handler was added when we ran into a stuck hardware condition on a
SLI-4 adapter. The host_reset will reset and reinit the pci function,
clearing the hardware condition.

Unfortunately, the host reset handler uses attach/detach code paths,
which makes scsi_add_host() and scsi_remove_host() calls. Meaning, a
host_reset will completely remove the scsi_host from the system. As a
new call to scsi_add_host() is made, the shost# changes, which results
in completely new scsi_devices and device names. All the older scsi
devices on the old shost# are now orphaned and unrecoverable.

We realize we need to re-implement the host_reset_handler so the scsi_host
stays registered across the host_reset, but that will be a rather
lengthy effort. In the short term, we had an immediate need to restore
the SLI-3 devices to their working behavior, with the easiest path being
to remove their host_reset handler.

Signed-off-by: Dick Kennedy <dick.kennedy@emulex.com>
Signed-off-by: James Smart <james.smart@emulex.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

3 files changed, 34 insertions, 3 deletions

diff --git a/drivers/scsi/lpfc/lpfc_crtn.h b/drivers/scsi/lpfc/lpfc_crtn.h
index 00665a5d92fd..665c88cf6404 100644
--- a/drivers/scsi/lpfc/lpfc_crtn.h
+++ b/drivers/scsi/lpfc/lpfc_crtn.h
@@ -354,6 +354,7 @@ void lpfc_free_sysfs_attr(struct lpfc_vport *);
 extern struct device_attribute *lpfc_hba_attrs[];
 extern struct device_attribute *lpfc_vport_attrs[];
 extern struct scsi_host_template lpfc_template;
+extern struct scsi_host_template lpfc_template_s3;
 extern struct scsi_host_template lpfc_vport_template;
 extern struct fc_function_template lpfc_transport_functions;
 extern struct fc_function_template lpfc_vport_transport_functions;
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 4ba91af11678..74672e0263ff 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -3257,12 +3257,17 @@ lpfc_create_port(struct lpfc_hba *phba, int instance, struct device *dev)
         struct Scsi_Host  *shost;
         int error = 0;
 
-        if (dev != &phba->pcidev->dev)
+        if (dev != &phba->pcidev->dev) {
                 shost = scsi_host_alloc(&lpfc_vport_template,
                                         sizeof(struct lpfc_vport));
-        else
-                shost = scsi_host_alloc(&lpfc_template,
+        } else {
+                if (phba->sli_rev == LPFC_SLI_REV4)
+                        shost = scsi_host_alloc(&lpfc_template,
                                         sizeof(struct lpfc_vport));
+                else
+                        shost = scsi_host_alloc(&lpfc_template_s3,
+                                        sizeof(struct lpfc_vport));
+        }
         if (!shost)
                 goto out;
 
diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index 4f9222eb2266..f6232991fb37 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -5857,6 +5857,31 @@ lpfc_disable_oas_lun(struct lpfc_hba *phba, struct lpfc_name *vport_wwpn,
         return false;
 }
 
+struct scsi_host_template lpfc_template_s3 = {
+        .module                 = THIS_MODULE,
+        .name                   = LPFC_DRIVER_NAME,
+        .info                   = lpfc_info,
+        .queuecommand           = lpfc_queuecommand,
+        .eh_abort_handler       = lpfc_abort_handler,
+        .eh_device_reset_handler = lpfc_device_reset_handler,
+        .eh_target_reset_handler = lpfc_target_reset_handler,
+        .eh_bus_reset_handler   = lpfc_bus_reset_handler,
+        .slave_alloc            = lpfc_slave_alloc,
+        .slave_configure        = lpfc_slave_configure,
+        .slave_destroy          = lpfc_slave_destroy,
+        .scan_finished          = lpfc_scan_finished,
+        .this_id                = -1,
+        .sg_tablesize           = LPFC_DEFAULT_SG_SEG_CNT,
+        .cmd_per_lun            = LPFC_CMD_PER_LUN,
+        .use_clustering         = ENABLE_CLUSTERING,
+        .shost_attrs            = lpfc_hba_attrs,
+        .max_sectors            = 0xFFFF,
+        .vendor_id              = LPFC_NL_VENDOR_ID,
+        .change_queue_depth     = scsi_change_queue_depth,
+        .use_blk_tags           = 1,
+        .track_queue_depth      = 1,
+};
+
 struct scsi_host_template lpfc_template = {
         .module                 = THIS_MODULE,
         .name                   = LPFC_DRIVER_NAME,