scsi: ibmvfc: Add Subordinate CRQ definitions

Subordinate Command Response Queues (Sub CRQ) are used in conjunction with
the primary CRQ when more than one queue is needed by the virtual I/O
adapter. Recent phyp firmware versions support Sub CRQ's with ibmvfc
adapters. This feature is a prerequisite for supporting multiple hardware
backed submission queues in the vfc adapter.

The Sub CRQ command element differs from the standard CRQ in that it is
32bytes long as opposed to 16bytes for the latter. Despite this extra
16bytes the ibmvfc protocol will use the original CRQ command element
mapped to the first 16bytes of the Sub CRQ element initially.

Add definitions for the Sub CRQ command element and queue.

Link: https://lore.kernel.org/r/20210114203148.246656-7-tyreld@linux.ibm.comReviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ibmvscsi/ibmvfc.h

@@ -650,6 +650,11 @@ struct ibmvfc_crq {
 	volatile __be64 ioba;
 } __packed __aligned(8);
 
+struct ibmvfc_sub_crq {
+	struct ibmvfc_crq crq;
+	__be64 reserved[2];
+} __packed __aligned(8);
+
 enum ibmvfc_ae_link_state {
 	IBMVFC_AE_LS_LINK_UP		= 0x01,
 	IBMVFC_AE_LS_LINK_BOUNCED	= 0x02,
@@ -761,12 +766,14 @@ struct ibmvfc_event_pool {
 enum ibmvfc_msg_fmt {
 	IBMVFC_CRQ_FMT = 0,
 	IBMVFC_ASYNC_FMT,
+	IBMVFC_SUB_CRQ_FMT,
 };
 
 union ibmvfc_msgs {
 	void *handle;
 	struct ibmvfc_crq *crq;
 	struct ibmvfc_async_crq *async;
+	struct ibmvfc_sub_crq *scrq;
 };
 
 struct ibmvfc_queue {
@@ -781,6 +788,20 @@ struct ibmvfc_queue {
 	struct list_head sent;
 	struct list_head free;
 	spinlock_t l_lock;
+
+	/* Sub-CRQ fields */
+	struct ibmvfc_host *vhost;
+	unsigned long cookie;
+	unsigned long vios_cookie;
+	unsigned long hw_irq;
+	unsigned long irq;
+	unsigned long hwq_id;
+	char name[32];
+};
+
+struct ibmvfc_scsi_channels {
+	struct ibmvfc_queue *scrqs;
+	unsigned int active_queues;
 };
 
 enum ibmvfc_host_action {