RDMA/rtrs: New function converting rtrs_addr to string

There is common code converting addresses of source machine and
destination machine to a string.  We already have a struct rtrs_addr to
store two addresses.  This patch introduces a new function that converts
two addresses into one string with struct rtrs_addr.

Link: https://lore.kernel.org/r/20210325153308.1214057-14-gi-oh.kim@ionos.comSigned-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/ulp/rtrs/rtrs-clt-sysfs.c

@@ -396,14 +396,13 @@ int rtrs_clt_create_sess_files(struct rtrs_clt_sess *sess)
 {
 	struct rtrs_clt *clt = sess->clt;
 	char str[NAME_MAX];
-	int err, cnt;
-
-	cnt = sockaddr_to_str((struct sockaddr *)&sess->s.src_addr,
-			      str, sizeof(str));
-	cnt += scnprintf(str + cnt, sizeof(str) - cnt, "@");
-	sockaddr_to_str((struct sockaddr *)&sess->s.dst_addr,
-			str + cnt, sizeof(str) - cnt);
+	int err;
+	struct rtrs_addr path = {
+		.src = &sess->s.src_addr,
+		.dst = &sess->s.dst_addr,
+	};
 
+	rtrs_addr_to_str(&path, str, sizeof(str));
 	err = kobject_init_and_add(&sess->kobj, &ktype_sess, clt->kobj_paths,
 				   "%s", str);
 	if (err) {

drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c

@@ -259,14 +259,13 @@ int rtrs_srv_create_sess_files(struct rtrs_srv_sess *sess)
 	struct rtrs_srv *srv = sess->srv;
 	struct rtrs_sess *s = &sess->s;
 	char str[NAME_MAX];
-	int err, cnt;
-
-	cnt = sockaddr_to_str((struct sockaddr *)&sess->s.dst_addr,
-			      str, sizeof(str));
-	cnt += scnprintf(str + cnt, sizeof(str) - cnt, "@");
-	sockaddr_to_str((struct sockaddr *)&sess->s.src_addr,
-			str + cnt, sizeof(str) - cnt);
+	int err;
+	struct rtrs_addr path = {
+		.src = &sess->s.dst_addr,
+		.dst = &sess->s.src_addr,
+	};
 
+	rtrs_addr_to_str(&path, str, sizeof(str));
 	err = rtrs_srv_create_once_sysfs_root_folders(sess);
 	if (err)
 		return err;

drivers/infiniband/ulp/rtrs/rtrs.c

@@ -463,6 +463,30 @@ int sockaddr_to_str(const struct sockaddr *addr, char *buf, size_t len)
 }
 EXPORT_SYMBOL(sockaddr_to_str);
 
+/**
+ * rtrs_addr_to_str() - convert rtrs_addr to a string "src@dst"
+ * @addr:	the rtrs_addr structure to be converted
+ * @buf:	string containing source and destination addr of a path
+ *		separated by '@' I.e. "ip:1.1.1.1@ip:1.1.1.2"
+ *		"ip:1.1.1.1@ip:1.1.1.2".
+ * @len:	string length
+ *
+ * The return value is the number of characters written into buf not
+ * including the trailing '\0'.
+ */
+int rtrs_addr_to_str(const struct rtrs_addr *addr, char *buf, size_t len)
+{
+	int cnt;
+
+	cnt = sockaddr_to_str((struct sockaddr *)addr->src,
+			      buf, len);
+	cnt += scnprintf(buf + cnt, len - cnt, "@");
+	sockaddr_to_str((struct sockaddr *)addr->dst,
+			buf + cnt, len - cnt);
+	return cnt;
+}
+EXPORT_SYMBOL(rtrs_addr_to_str);
+
 /**
  * rtrs_addr_to_sockaddr() - convert path string "src,dst" or "src@dst"
  * to sockaddreses

drivers/infiniband/ulp/rtrs/rtrs.h

@@ -184,4 +184,5 @@ int rtrs_addr_to_sockaddr(const char *str, size_t len, u16 port,
 			  struct rtrs_addr *addr);
 
 int sockaddr_to_str(const struct sockaddr *addr, char *buf, size_t len);
+int rtrs_addr_to_str(const struct rtrs_addr *addr, char *buf, size_t len);
 #endif