[S390] cio: Use add_uevent_var.

Convert ccw_uevent to use add_uevent_var and adapt snprint_alias.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/device.c

@@ -56,13 +56,12 @@ ccw_bus_match (struct device * dev, struct device_driver * drv)
 /* Store modalias string delimited by prefix/suffix string into buffer with
  * specified size. Return length of resulting string (excluding trailing '\0')
  * even if string doesn't fit buffer (snprintf semantics). */
-static int snprint_alias(char *buf, size_t size, const char *prefix,
+static int snprint_alias(char *buf, size_t size,
 			 struct ccw_device_id *id, const char *suffix)
 {
 	int len;
 
-	len = snprintf(buf, size, "%sccw:t%04Xm%02X", prefix, id->cu_type,
-		       id->cu_model);
+	len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
 	if (len > size)
 		return len;
 	buf += len;
@@ -85,53 +84,40 @@ static int ccw_uevent(struct device *dev, char **envp, int num_envp,
 	struct ccw_device *cdev = to_ccwdev(dev);
 	struct ccw_device_id *id = &(cdev->id);
 	int i = 0;
-	int len;
+	int len = 0;
+	int ret;
+	char modalias_buf[30];
 
 	/* CU_TYPE= */
-	len = snprintf(buffer, buffer_size, "CU_TYPE=%04X", id->cu_type) + 1;
-	if (len > buffer_size || i >= num_envp)
-		return -ENOMEM;
-	envp[i++] = buffer;
-	buffer += len;
-	buffer_size -= len;
+	ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
+			     "CU_TYPE=%04X", id->cu_type);
+	if (ret)
+		return ret;
 
 	/* CU_MODEL= */
-	len = snprintf(buffer, buffer_size, "CU_MODEL=%02X", id->cu_model) + 1;
-	if (len > buffer_size || i >= num_envp)
-		return -ENOMEM;
-	envp[i++] = buffer;
-	buffer += len;
-	buffer_size -= len;
+	ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
+			     "CU_MODEL=%02X", id->cu_model);
+	if (ret)
+		return ret;
 
 	/* The next two can be zero, that's ok for us */
 	/* DEV_TYPE= */
-	len = snprintf(buffer, buffer_size, "DEV_TYPE=%04X", id->dev_type) + 1;
-	if (len > buffer_size || i >= num_envp)
-		return -ENOMEM;
-	envp[i++] = buffer;
-	buffer += len;
-	buffer_size -= len;
+	ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
+			     "DEV_TYPE=%04X", id->dev_type);
+	if (ret)
+		return ret;
 
 	/* DEV_MODEL= */
-	len = snprintf(buffer, buffer_size, "DEV_MODEL=%02X",
-			(unsigned char) id->dev_model) + 1;
-	if (len > buffer_size || i >= num_envp)
-		return -ENOMEM;
-	envp[i++] = buffer;
-	buffer += len;
-	buffer_size -= len;
+	ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
+			     "DEV_MODEL=%02X", id->dev_model);
+	if (ret)
+		return ret;
 
 	/* MODALIAS=  */
-	len = snprint_alias(buffer, buffer_size, "MODALIAS=", id, "") + 1;
-	if (len > buffer_size || i >= num_envp)
-		return -ENOMEM;
-	envp[i++] = buffer;
-	buffer += len;
-	buffer_size -= len;
-
-	envp[i] = NULL;
-
-	return 0;
+	snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
+	ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
+			     "MODALIAS=%s", modalias_buf);
+	return ret;
 }
 
 struct bus_type ccw_bus_type;
@@ -280,7 +266,7 @@ modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 	struct ccw_device_id *id = &(cdev->id);
 	int len;
 
-	len = snprint_alias(buf, PAGE_SIZE, "", id, "\n") + 1;
+	len = snprint_alias(buf, PAGE_SIZE, id, "\n") + 1;
 
 	return len > PAGE_SIZE ? PAGE_SIZE : len;
 }