scsi: remove port from scsi_dev dynamically

Current implementation supports only adding port to scsi_dev.
This change is required to support dynamic remapping of portals.

Change-Id: Idce49aeae43c8861ebe2807df853694f7bacf884
Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-on: https://review.gerrithub.io/379931
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Ziye Yang <optimistyzy@gmail.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>

include/spdk/scsi.h

@@ -179,6 +179,7 @@ void spdk_scsi_dev_queue_mgmt_task(struct spdk_scsi_dev *dev, struct spdk_scsi_t
 				   enum spdk_scsi_task_func func);
 void spdk_scsi_dev_queue_task(struct spdk_scsi_dev *dev, struct spdk_scsi_task *task);
 int spdk_scsi_dev_add_port(struct spdk_scsi_dev *dev, uint64_t id, const char *name);
+int spdk_scsi_dev_delete_port(struct spdk_scsi_dev *dev, uint64_t id);
 struct spdk_scsi_port *spdk_scsi_dev_find_port_by_id(struct spdk_scsi_dev *dev, uint64_t id);
 void spdk_scsi_dev_print(struct spdk_scsi_dev *dev);
 int spdk_scsi_dev_allocate_io_channels(struct spdk_scsi_dev *dev);

lib/scsi/dev.c

@@ -220,6 +220,20 @@ spdk_scsi_dev_queue_task(struct spdk_scsi_dev *dev,
 	}
 }
 
+static struct spdk_scsi_port *
+spdk_scsi_dev_find_free_port(struct spdk_scsi_dev *dev)
+{
+	int i;
+
+	for (i = 0; i < SPDK_SCSI_DEV_MAX_PORTS; i++) {
+		if (!dev->port[i].is_used) {
+			return &dev->port[i];
+		}
+	}
+
+	return NULL;
+}
+
 int
 spdk_scsi_dev_add_port(struct spdk_scsi_dev *dev, uint64_t id, const char *name)
 {
@@ -231,7 +245,17 @@ spdk_scsi_dev_add_port(struct spdk_scsi_dev *dev, uint64_t id, const char *name)
 		return -1;
 	}
 
-	port = &dev->port[dev->num_ports];
+	port = spdk_scsi_dev_find_port_by_id(dev, id);
+	if (port != NULL) {
+		SPDK_ERRLOG("device already has port(%" PRIu64 ")\n", id);
+		return -1;
+	}
+
+	port = spdk_scsi_dev_find_free_port(dev);
+	if (port == NULL) {
+		assert(false);
+		return -1;
+	}
 
 	rc = spdk_scsi_port_construct(port, id, dev->num_ports, name);
 	if (rc != 0) {
@@ -242,12 +266,33 @@ spdk_scsi_dev_add_port(struct spdk_scsi_dev *dev, uint64_t id, const char *name)
 	return 0;
 }
 
+int
+spdk_scsi_dev_delete_port(struct spdk_scsi_dev *dev, uint64_t id)
+{
+	struct spdk_scsi_port *port;
+
+	port = spdk_scsi_dev_find_port_by_id(dev, id);
+	if (port == NULL) {
+		SPDK_ERRLOG("device does not have specified port(%" PRIu64 ")\n", id);
+		return -1;
+	}
+
+	spdk_scsi_port_destruct(port);
+
+	dev->num_ports--;
+
+	return 0;
+}
+
 struct spdk_scsi_port *
 spdk_scsi_dev_find_port_by_id(struct spdk_scsi_dev *dev, uint64_t id)
 {
 	int i;
 
-	for (i = 0; i < dev->num_ports; i++) {
+	for (i = 0; i < SPDK_SCSI_DEV_MAX_PORTS; i++) {
+		if (!dev->port[i].is_used) {
+			continue;
+		}
 		if (dev->port[i].id == id) {
 			return &dev->port[i];
 		}

lib/scsi/port.c

@@ -76,12 +76,19 @@ spdk_scsi_port_construct(struct spdk_scsi_port *port, uint64_t id, uint16_t inde
 		return -1;
 	}
 
+	port->is_used = 1;
 	port->id = id;
 	port->index = index;
 	snprintf(port->name, sizeof(port->name), "%s", name);
 	return 0;
 }
 
+void
+spdk_scsi_port_destruct(struct spdk_scsi_port *port)
+{
+	memset(port, 0, sizeof(struct spdk_scsi_port));
+}
+
 const char *
 spdk_scsi_port_get_name(const struct spdk_scsi_port *port)
 {

lib/scsi/scsi_bdev.c

@@ -452,10 +452,14 @@ spdk_bdev_scsi_inquiry(struct spdk_bdev *bdev, struct spdk_scsi_task *task,
 			hlen = 4;
 
 			/* Identification descriptor list */
-			for (i = 0; i < dev->num_ports; i++) {
+			for (i = 0; i < SPDK_SCSI_DEV_MAX_PORTS; i++) {
 				struct spdk_scsi_port_desc *sdesc;
 				struct spdk_scsi_tgt_port_desc *pdesc;
 
+				if (!dev->port[i].is_used) {
+					continue;
+				}
+
 				/* Identification descriptor N */
 				sdesc = (struct spdk_scsi_port_desc *)&vpage->params[len];
 

lib/scsi/scsi_internal.h

@@ -51,7 +51,7 @@ enum {
 };
 
 struct spdk_scsi_port {
-	struct spdk_scsi_dev	*dev;
+	uint8_t			is_used;
 	uint64_t		id;
 	uint16_t		index;
 	char			name[SPDK_SCSI_PORT_MAX_NAME_LENGTH];
@@ -159,6 +159,7 @@ struct spdk_scsi_dev *spdk_scsi_dev_get_list(void);
 
 int spdk_scsi_port_construct(struct spdk_scsi_port *port, uint64_t id,
 			     uint16_t index, const char *name);
+void spdk_scsi_port_destruct(struct spdk_scsi_port *port);
 
 int spdk_bdev_scsi_execute(struct spdk_bdev *bdev, struct spdk_scsi_task *task);
 int spdk_bdev_scsi_reset(struct spdk_bdev *bdev, struct spdk_scsi_task *task);