tcmu: Add Type of reconfig into netlink

This patch adds more info about the attribute being changed,
so that usersapce can easily figure out what is happening.
Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Reviewed-By: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_user.c

@@ -1176,7 +1176,8 @@ static int tcmu_release(struct uio_info *info, struct inode *inode)
 	return 0;
 }
 
-static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, int minor)
+static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name,
+			      int minor, int type)
 {
 	struct sk_buff *skb;
 	void *msg_header;
@@ -1198,6 +1199,10 @@ static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, int mino
 	if (ret < 0)
 		goto free_skb;
 
+	ret = nla_put_u32(skb, TCMU_ATTR_TYPE, type);
+	if (ret < 0)
+		goto free_skb;
+
 	genlmsg_end(skb, msg_header);
 
 	ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0,
@@ -1301,7 +1306,7 @@ static int tcmu_configure_device(struct se_device *dev)
 	kref_get(&udev->kref);
 
 	ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name,
-				 udev->uio_info.uio_dev->minor);
+				 udev->uio_info.uio_dev->minor, NO_RECONFIG);
 	if (ret)
 		goto err_netlink;
 
@@ -1383,7 +1388,7 @@ static void tcmu_free_device(struct se_device *dev)
 
 	if (tcmu_dev_configured(udev)) {
 		tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name,
-				   udev->uio_info.uio_dev->minor);
+				   udev->uio_info.uio_dev->minor, NO_RECONFIG);
 
 		uio_unregister_device(&udev->uio_info);
 	}
@@ -1577,7 +1582,8 @@ static ssize_t tcmu_dev_path_store(struct config_item *item, const char *page,
 	if (tcmu_dev_configured(udev)) {
 		ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE,
 					 udev->uio_info.name,
-					 udev->uio_info.uio_dev->minor);
+					 udev->uio_info.uio_dev->minor,
+					 CONFIG_PATH);
 		if (ret) {
 			pr_err("Unable to reconfigure device\n");
 			return ret;
@@ -1615,7 +1621,8 @@ static ssize_t tcmu_dev_size_store(struct config_item *item, const char *page,
 	if (tcmu_dev_configured(udev)) {
 		ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE,
 					 udev->uio_info.name,
-					 udev->uio_info.uio_dev->minor);
+					 udev->uio_info.uio_dev->minor,
+					 CONFIG_SIZE);
 		if (ret) {
 			pr_err("Unable to reconfigure device\n");
 			return ret;
@@ -1654,7 +1661,8 @@ static ssize_t tcmu_emulate_write_cache_store(struct config_item *item,
 	if (tcmu_dev_configured(udev)) {
 		ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE,
 					 udev->uio_info.name,
-					 udev->uio_info.uio_dev->minor);
+					 udev->uio_info.uio_dev->minor,
+					 CONFIG_WRITECACHE);
 		if (ret) {
 			pr_err("Unable to reconfigure device\n");
 			return ret;

include/uapi/linux/target_core_user.h

@@ -139,8 +139,16 @@ enum tcmu_genl_attr {
 	TCMU_ATTR_UNSPEC,
 	TCMU_ATTR_DEVICE,
 	TCMU_ATTR_MINOR,
+	TCMU_ATTR_TYPE,
 	__TCMU_ATTR_MAX,
 };
 #define TCMU_ATTR_MAX (__TCMU_ATTR_MAX - 1)
 
+enum tcmu_reconfig_types {
+	NO_RECONFIG,
+	CONFIG_PATH,
+	CONFIG_SIZE,
+	CONFIG_WRITECACHE,
+};
+
 #endif