[S390] set modalias for ccw bus uevents.

Add the MODALIAS environment variable for ccw bus uevents.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 646da56404015d7d614b3c469c1305962ee8e085..688945662c151e16abbc65074dba3b6ed0ac06c8 100644 (file)
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -52,53 +52,81 @@ ccw_bus_match (struct device * dev, struct device_driver * drv)
        return 1;
 }
 
-/*
- * Hotplugging interface for ccw devices.
- * Heavily modeled on pci and usb hotplug.
- */
-static int
-ccw_uevent (struct device *dev, char **envp, int num_envp,
-            char *buffer, int buffer_size)
+/* 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,
+                        struct ccw_device_id *id, const char *suffix)
 {
-       struct ccw_device *cdev = to_ccwdev(dev);
-       int i = 0;
-       int length = 0;
+       int len;
 
-       if (!cdev)
-               return -ENODEV;
+       len = snprintf(buf, size, "%sccw:t%04Xm%02X", prefix, id->cu_type,
+                      id->cu_model);
+       if (len > size)
+               return len;
+       buf += len;
+       size -= len;
 
-       /* what we want to pass to /sbin/hotplug */
+       if (id->dev_type != 0)
+               len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
+                               id->dev_model, suffix);
+       else
+               len += snprintf(buf, size, "dtdm%s", suffix);
 
-       envp[i++] = buffer;
-       length += scnprintf(buffer, buffer_size - length, "CU_TYPE=%04X",
-                          cdev->id.cu_type);
-       if ((buffer_size - length <= 0) || (i >= num_envp))
-               return -ENOMEM;
-       ++length;
-       buffer += length;
+       return len;
+}
 
+/* Set up environment variables for ccw device uevent. Return 0 on success,
+ * non-zero otherwise. */
+static int ccw_uevent(struct device *dev, char **envp, int num_envp,
+                     char *buffer, int buffer_size)
+{
+       struct ccw_device *cdev = to_ccwdev(dev);
+       struct ccw_device_id *id = &(cdev->id);
+       int i = 0;
+       int len;
+
+       /* 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;
-       length += scnprintf(buffer, buffer_size - length, "CU_MODEL=%02X",
-                          cdev->id.cu_model);
-       if ((buffer_size - length <= 0) || (i >= num_envp))
+       buffer += len;
+       buffer_size -= len;
+
+       /* CU_MODEL= */
+       len = snprintf(buffer, buffer_size, "CU_MODEL=%02X", id->cu_model) + 1;
+       if (len > buffer_size || i >= num_envp)
                return -ENOMEM;
-       ++length;
-       buffer += length;
+       envp[i++] = buffer;
+       buffer += len;
+       buffer_size -= len;
 
        /* The next two can be zero, that's ok for us */
-       envp[i++] = buffer;
-       length += scnprintf(buffer, buffer_size - length, "DEV_TYPE=%04X",
-                          cdev->id.dev_type);
-       if ((buffer_size - length <= 0) || (i >= num_envp))
+       /* DEV_TYPE= */
+       len = snprintf(buffer, buffer_size, "DEV_TYPE=%04X", id->dev_type) + 1;
+       if (len > buffer_size || i >= num_envp)
                return -ENOMEM;
-       ++length;
-       buffer += length;
+       envp[i++] = buffer;
+       buffer += len;
+       buffer_size -= len;
 
+       /* 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;
-       length += scnprintf(buffer, buffer_size - length, "DEV_MODEL=%02X",
-                          cdev->id.dev_model);
-       if ((buffer_size - length <= 0) || (i >= num_envp))
+       buffer += len;
+       buffer_size -= len;
+
+       /* 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;
 
@@ -251,16 +279,11 @@ modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 {
        struct ccw_device *cdev = to_ccwdev(dev);
        struct ccw_device_id *id = &(cdev->id);
-       int ret;
+       int len;
 
-       ret = sprintf(buf, "ccw:t%04Xm%02X",
-                       id->cu_type, id->cu_model);
-       if (id->dev_type != 0)
-               ret += sprintf(buf + ret, "dt%04Xdm%02X\n",
-                               id->dev_type, id->dev_model);
-       else
-               ret += sprintf(buf + ret, "dtdm\n");
-       return ret;
+       len = snprint_alias(buf, PAGE_SIZE, "", id, "\n") + 1;
+
+       return len > PAGE_SIZE ? PAGE_SIZE : len;
 }
 
 static ssize_t