[PATCH] USB: Changes to core/config.c (9 of 9)

This patch implements the change discussed last weekend.  Rather than
allocating separate memory areas for the "extra" descriptors and copying
the descriptor contents, it simply makes the "extra" pointers refer to
memory within the rawdescriptor arrays.

drivers/usb/core/config.c

@@ -17,7 +17,7 @@ static int usb_parse_endpoint(struct usb_host_endpoint *endpoint, unsigned char
 	unsigned char *buffer0 = buffer;
 	struct usb_descriptor_header *header;
 	unsigned char *begin;
-	int len, numskipped;
+	int numskipped;
 
 	header = (struct usb_descriptor_header *)buffer;
 	if (header->bDescriptorType != USB_DT_ENDPOINT) {
@@ -65,19 +65,8 @@ static int usb_parse_endpoint(struct usb_host_endpoint *endpoint, unsigned char
 	}
 	if (numskipped) {
 		dbg("skipped %d class/vendor specific endpoint descriptors", numskipped);
-
-		/* Copy any unknown descriptors into a storage area for drivers */
-		/*  to later parse */
-		len = buffer - begin;
-
-		endpoint->extra = kmalloc(len, GFP_KERNEL);
-		if (!endpoint->extra) {
-			err("couldn't allocate memory for endpoint extra descriptors");
-			return -ENOMEM;
-		}
-
-		memcpy(endpoint->extra, begin, len);
-		endpoint->extralen = len;
+		endpoint->extra = begin;
+		endpoint->extralen = buffer - begin;
 	}
 
 	return buffer - buffer0;
@@ -87,22 +76,14 @@ static void usb_release_intf(struct device *dev)
 {
 	struct usb_interface *intf;
 	int j;
-	int k;
 
 	intf = to_usb_interface(dev);
 
 	if (intf->altsetting) {
 		for (j = 0; j < intf->num_altsetting; j++) {
 			struct usb_host_interface *as = &intf->altsetting[j];
-			if (as->extra)
-				kfree(as->extra);
-
-			if (as->endpoint) {
-				for (k = 0; k < as->desc.bNumEndpoints; k++)
-					if (as->endpoint[k].extra)
-						kfree(as->endpoint[k].extra);
-				kfree(as->endpoint);
-			}
+
+			kfree(as->endpoint);
 		}
 		kfree(intf->altsetting);
 	}
@@ -183,18 +164,8 @@ static int usb_parse_interface(struct usb_host_config *config, unsigned char *bu
 	}
 	if (numskipped) {
 		dbg("skipped %d class/vendor specific interface descriptors", numskipped);
-
-		/* Copy any unknown descriptors into a storage area for */
-		/*  drivers to later parse */
-		len = buffer - begin;
-		ifp->extra = kmalloc(len, GFP_KERNEL);
-
-		if (!ifp->extra) {
-			err("couldn't allocate memory for interface extra descriptors");
-			return -ENOMEM;
-		}
-		memcpy(ifp->extra, begin, len);
-		ifp->extralen = len;
+		ifp->extra = begin;
+		ifp->extralen = buffer - begin;
 	}
 
 	if (ifp->desc.bNumEndpoints > USB_MAXENDPOINTS) {
@@ -355,18 +326,8 @@ int usb_parse_configuration(struct usb_host_config *config, char *buffer, int si
 	}
 	if (numskipped) {
 		dbg("skipped %d class/vendor specific configuration descriptors", numskipped);
-
-		/* Copy any unknown descriptors into a storage area for */
-		/*  drivers to later parse */
-		len = buffer - begin;
-		config->extra = kmalloc(len, GFP_KERNEL);
-		if (!config->extra) {
-			err("couldn't allocate memory for config extra descriptors");
-			return -ENOMEM;
-		}
-
-		memcpy(config->extra, begin, len);
-		config->extralen = len;
+		config->extra = begin;
+		config->extralen = buffer - begin;
 	}
 
 	/* Parse all the interface/altsetting descriptors */
@@ -418,7 +379,6 @@ void usb_destroy_configuration(struct usb_device *dev)
 			if (ifp)
 				put_device(&ifp->dev);
 		}
-		kfree(cf->extra);
 	}
 	kfree(dev->config);
 }