[PATCH 2/5] ibmvfc: Add NOOP command support

[Dave Marquardt via B4 Relay]

From: Dave Marquardt <davemarq at linux.ibm.com>

- Add VFC_NOOP command support
- Add KUnit tests for VFC_NOOP command
---
 drivers/scsi/ibmvscsi/ibmvfc.c       | 23 +++++++++++++----------
 drivers/scsi/ibmvscsi/ibmvfc.h       | 13 +++++++++++++
 drivers/scsi/ibmvscsi/ibmvfc_kunit.c | 27 +++++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 10 deletions(-)

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 3ac376ba2c62..808301fa452d 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -189,13 +189,6 @@ static long h_reg_sub_crq(unsigned long unit_address, unsigned long ioba,
 	return rc;
 }
 
-static int ibmvfc_check_caps(struct ibmvfc_host *vhost, unsigned long cap_flags)
-{
-	u64 host_caps = be64_to_cpu(vhost->login_buf->resp.capabilities);
-
-	return (host_caps & cap_flags) ? 1 : 0;
-}
-
 static struct ibmvfc_fcp_cmd_iu *ibmvfc_get_fcp_iu(struct ibmvfc_host *vhost,
 						   struct ibmvfc_cmd *vfc_cmd)
 {
@@ -1512,7 +1505,9 @@ static void ibmvfc_set_login_info(struct ibmvfc_host *vhost)
 		login_info->flags |= cpu_to_be16(IBMVFC_CLIENT_MIGRATED);
 
 	login_info->max_cmds = cpu_to_be32(max_cmds);
-	login_info->capabilities = cpu_to_be64(IBMVFC_CAN_MIGRATE | IBMVFC_CAN_SEND_VF_WWPN);
+	login_info->capabilities =
+		cpu_to_be64(IBMVFC_CAN_MIGRATE | IBMVFC_CAN_SEND_VF_WWPN |
+			    IBMVFC_CAN_USE_NOOP_CMD);
 
 	if (vhost->mq_enabled || vhost->using_channels)
 		login_info->capabilities |= cpu_to_be64(IBMVFC_CAN_USE_CHANNELS);
@@ -3461,8 +3456,8 @@ EXPORT_SYMBOL_IF_KUNIT(ibmvfc_handle_async);
  * @evt_doneq:	Event done queue
  *
 **/
-static void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost,
-			      struct list_head *evt_doneq)
+VISIBLE_IF_KUNIT void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost,
+					struct list_head *evt_doneq)
 {
 	long rc;
 	struct ibmvfc_event *evt = (struct ibmvfc_event *)be64_to_cpu(crq->ioba);
@@ -3520,6 +3515,13 @@ static void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost,
 	if (crq->format == IBMVFC_ASYNC_EVENT)
 		return;
 
+	if (crq->format == IBMVFC_VFC_NOOP) {
+		if (!ibmvfc_check_caps(vhost, IBMVFC_SUPPORT_NOOP_CMD))
+			dev_err(vhost->dev,
+				"Received unexpected NOOP command from partner\n");
+		return;
+	}
+
 	/* The only kind of payload CRQs we should get are responses to
 	 * things we send. Make sure this response is to something we
 	 * actually sent
@@ -3540,6 +3542,7 @@ static void ibmvfc_handle_crq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost,
 	list_move_tail(&evt->queue_list, evt_doneq);
 	spin_unlock(&evt->queue->l_lock);
 }
+EXPORT_SYMBOL_IF_KUNIT(ibmvfc_handle_crq);
 
 /**
  * ibmvfc_scan_finished - Check if the device scan is done.
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h
index 29932284a4c9..cd0917f70c6d 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.h
+++ b/drivers/scsi/ibmvscsi/ibmvfc.h
@@ -180,6 +180,7 @@ struct ibmvfc_npiv_login {
 #define IBMVFC_CAN_HANDLE_FPIN		0x04
 #define IBMVFC_CAN_USE_MAD_VERSION	0x08
 #define IBMVFC_CAN_SEND_VF_WWPN		0x10
+#define IBMVFC_CAN_USE_NOOP_CMD		0x200
 	__be64 node_name;
 	struct srp_direct_buf async;
 	u8 partition_name[IBMVFC_MAX_NAME];
@@ -226,6 +227,7 @@ struct ibmvfc_npiv_login_resp {
 #define IBMVFC_MAD_VERSION_CAP		0x20
 #define IBMVFC_HANDLE_VF_WWPN		0x40
 #define IBMVFC_CAN_SUPPORT_CHANNELS	0x80
+#define IBMVFC_SUPPORT_NOOP_CMD		0x1000
 	__be32 max_cmds;
 	__be32 scsi_id_sz;
 	__be64 max_dma_len;
@@ -621,6 +623,7 @@ struct ibmvfc_trace_entry {
 enum ibmvfc_crq_formats {
 	IBMVFC_CMD_FORMAT		= 0x01,
 	IBMVFC_ASYNC_EVENT	= 0x02,
+	IBMVFC_VFC_NOOP		= 0x03,
 	IBMVFC_MAD_FORMAT		= 0x04,
 };
 
@@ -946,6 +949,13 @@ struct ibmvfc_host {
 			dev_err((vhost)->dev, ##__VA_ARGS__); \
 	} while (0)
 
+static inline int ibmvfc_check_caps(struct ibmvfc_host *vhost, unsigned long cap_flags)
+{
+	u64 host_caps = be64_to_cpu(vhost->login_buf->resp.capabilities);
+
+	return (host_caps & cap_flags) ? 1 : 0;
+}
+
 #define ENTER DBG_CMD(printk(KERN_INFO IBMVFC_NAME": Entering %s\n", __func__))
 #define LEAVE DBG_CMD(printk(KERN_INFO IBMVFC_NAME": Leaving %s\n", __func__))
 
@@ -960,6 +970,9 @@ struct ibmvfc_host {
 #ifdef VISIBLE_IF_KUNIT
 VISIBLE_IF_KUNIT void ibmvfc_handle_async(struct ibmvfc_async_crq *crq, struct ibmvfc_host *vhost);
 VISIBLE_IF_KUNIT struct list_head *ibmvfc_get_headp(void);
+VISIBLE_IF_KUNIT void ibmvfc_handle_crq(struct ibmvfc_crq *crq,
+					struct ibmvfc_host *vhost,
+					struct list_head *evt_doneq);
 #endif
 
 #endif
diff --git a/drivers/scsi/ibmvscsi/ibmvfc_kunit.c b/drivers/scsi/ibmvscsi/ibmvfc_kunit.c
index 1c238896049f..3359e4ebebe2 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc_kunit.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc_kunit.c
@@ -79,8 +79,35 @@ static void ibmvfc_handle_fpin_event_test(struct kunit *test)
 	}
 }
 
+/**
+ * ibmvfc_noop_test - unit test for VFC_NOOP command
+ * @test: pointer to kunit structure
+ *
+ * Return: void
+ */
+static void ibmvfc_noop_test(struct kunit *test)
+{
+	struct ibmvfc_host *vhost;
+	struct list_head *queue;
+	struct ibmvfc_crq crq;
+	struct list_head *headp;
+	LIST_HEAD(evtq);
+
+	headp = ibmvfc_get_headp();
+	queue = headp->next;
+	vhost = container_of(queue, struct ibmvfc_host, queue);
+
+	KUNIT_EXPECT_TRUE(test, ibmvfc_check_caps(vhost, IBMVFC_SUPPORT_NOOP_CMD));
+
+	crq.valid = 0x80;
+	crq.format = IBMVFC_VFC_NOOP;
+	crq.ioba = cpu_to_be64(NULL);
+	ibmvfc_handle_crq(&crq, vhost, &evtq);
+}
+
 static struct kunit_case ibmvfc_fpin_test_cases[] = {
 	KUNIT_CASE(ibmvfc_handle_fpin_event_test),
+	KUNIT_CASE(ibmvfc_noop_test),
 	{},
 };
 

-- 
2.53.0