[PATCH] usb gadget: ethernet/rndis updates

Updates to the Ethernet/RNDIS gadget driver (mostly for RNDIS):

  - Fix brown-paper bag goof with RNDIS packet TX ... the wrong length
    field got set, so Windows would ignore data packets it received.

  - More consistent handling of CDC output filters (but not yet hooking
    things up so RNDIS uses the mechanism).

  - Zerocopy RX for RNDIS packets too (saving CPU cycles).

  - Use the pre-allocated interrupt/status request and buffer, rather
    than allocating and freeing one of each every few seconds (which
    could fail).

  - Some more "sparse" tweaks, making both dual-speed and single-speed
    configurations happier.

  - RNDIS speeds are reported in units of 100bps, not bps.

Plus two minor cleanups (whitespace, messaging).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/ether.c

@@ -100,6 +100,8 @@ static const char driver_desc [] = DRIVER_DESC;
 
 /* CDC and RNDIS support the same host-chosen outgoing packet filters. */
 #define	DEFAULT_FILTER	(USB_CDC_PACKET_TYPE_BROADCAST \
+ 			|USB_CDC_PACKET_TYPE_ALL_MULTICAST \
+ 			|USB_CDC_PACKET_TYPE_PROMISCUOUS \
  			|USB_CDC_PACKET_TYPE_DIRECTED)
 
 
@@ -322,12 +324,18 @@ module_param (qmult, uint, S_IRUGO|S_IWUSR);
 /* also defer IRQs on highspeed TX */
 #define TX_DELAY	qmult
 
-#define	BITRATE(g)	(((g)->speed == USB_SPEED_HIGH) ? HS_BPS : FS_BPS)
+static inline int BITRATE(struct usb_gadget *g)
+{
+	return (g->speed == USB_SPEED_HIGH) ? HS_BPS : FS_BPS;
+}
 
 #else	/* full speed (low speed doesn't do bulk) */
 #define qlen(gadget) DEFAULT_QLEN
 
-#define	BITRATE(g)	FS_BPS
+static inline int BITRATE(struct usb_gadget *g)
+{
+	return FS_BPS;
+}
 #endif
 
 
@@ -1167,7 +1175,7 @@ eth_set_config (struct eth_dev *dev, unsigned number, int gfp_flags)
 	eth_reset_config (dev);
 
 	/* default:  pass all packets, no multicast filtering */
-	dev->cdc_filter = 0x000f;
+	dev->cdc_filter = DEFAULT_FILTER;
 
 	switch (number) {
 	case DEV_CONFIG_VALUE:
@@ -1343,9 +1351,9 @@ eth_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 	struct eth_dev		*dev = get_gadget_data (gadget);
 	struct usb_request	*req = dev->req;
 	int			value = -EOPNOTSUPP;
-	u16			wIndex = ctrl->wIndex;
-	u16			wValue = ctrl->wValue;
-	u16			wLength = ctrl->wLength;
+	u16			wIndex = (__force u16) ctrl->wIndex;
+	u16			wValue = (__force u16) ctrl->wValue;
+	u16			wLength = (__force u16) ctrl->wLength;
 
 	/* descriptors just go into the pre-allocated ep0 buffer,
 	 * while config change events may enable network traffic.
@@ -1693,7 +1701,7 @@ rx_submit (struct eth_dev *dev, struct usb_request *req, int gfp_flags)
 	
 	/* Some platforms perform better when IP packets are aligned,
 	 * but on at least one, checksumming fails otherwise.  Note:
-	 * this doesn't account for variable-sized RNDIS headers.
+	 * RNDIS headers involve variable numbers of LE32 values.
 	 */
 	skb_reserve(skb, NET_IP_ALIGN);
 
@@ -1730,9 +1738,11 @@ static void rx_complete (struct usb_ep *ep, struct usb_request *req)
 #ifdef CONFIG_USB_ETH_RNDIS
 		/* we know MaxPacketsPerTransfer == 1 here */
 		if (dev->rndis)
-			rndis_rm_hdr (req->buf, &(skb->len));
+			status = rndis_rm_hdr (skb);
 #endif
-		if (ETH_HLEN > skb->len || skb->len > ETH_FRAME_LEN) {
+		if (status < 0
+				|| ETH_HLEN > skb->len
+				|| skb->len > ETH_FRAME_LEN) {
 			dev->stats.rx_errors++;
 			dev->stats.rx_length_errors++;
 			DEBUG (dev, "rx length %d\n", skb->len);
@@ -2047,38 +2057,20 @@ rndis_control_ack_complete (struct usb_ep *ep, struct usb_request *req)
 		DEBUG ((struct eth_dev *) ep->driver_data,
 			"rndis control ack complete --> %d, %d/%d\n",
 			req->status, req->actual, req->length);
-
-	usb_ep_free_buffer(ep, req->buf, req->dma, 8);
-	usb_ep_free_request(ep, req);
 }
 
 static int rndis_control_ack (struct net_device *net)
 {
 	struct eth_dev          *dev = netdev_priv(net);
 	u32                     length;
-	struct usb_request      *resp;
+	struct usb_request      *resp = dev->stat_req;
 	
 	/* in case RNDIS calls this after disconnect */
-	if (!dev->status_ep) {
+	if (!dev->status) {
 		DEBUG (dev, "status ENODEV\n");
 		return -ENODEV;
 	}
 
-	/* Allocate memory for notification ie. ACK */
-	resp = usb_ep_alloc_request (dev->status_ep, GFP_ATOMIC);
-	if (!resp) {
-		DEBUG (dev, "status ENOMEM\n");
-		return -ENOMEM;
-	}
-	
-	resp->buf = usb_ep_alloc_buffer (dev->status_ep, 8,
-					 &resp->dma, GFP_ATOMIC);
-	if (!resp->buf) {
-		DEBUG (dev, "status buf ENOMEM\n");
-		usb_ep_free_request (dev->status_ep, resp);
-		return -ENOMEM;
-	}
-	
 	/* Send RNDIS RESPONSE_AVAILABLE notification;
 	 * USB_CDC_NOTIFY_RESPONSE_AVAILABLE should work too
 	 */
@@ -2113,7 +2105,7 @@ static void eth_start (struct eth_dev *dev, int gfp_flags)
 	if (dev->rndis) {
 		rndis_set_param_medium (dev->rndis_config,
 					NDIS_MEDIUM_802_3,
-					BITRATE(dev->gadget));
+					BITRATE(dev->gadget)/100);
 		rndis_send_media_state (dev, 1);
 	}
 #endif	

drivers/usb/gadget/rndis.c

@@ -37,6 +37,7 @@
 #include <asm/io.h>
 #include <asm/byteorder.h>
 #include <asm/system.h>
+#include <asm/unaligned.h>
 
 
 #undef	RNDIS_PM
@@ -165,7 +166,7 @@ static int gen_ndis_query_resp (int configNr, u32 OID, rndis_resp_t *r)
 		
 	/* mandatory */
 	case OID_GEN_LINK_SPEED:
-		DEBUG("%s: OID_GEN_LINK_SPEED\n", __FUNCTION__);
+//		DEBUG("%s: OID_GEN_LINK_SPEED\n", __FUNCTION__);
 		length = 4;
 		if (rndis_per_dev_params [configNr].media_state
 			== NDIS_MEDIA_STATE_DISCONNECTED)
@@ -729,7 +730,7 @@ static int gen_ndis_set_resp (u8 configNr, u32 OID, u8 *buf, u32 buf_len,
 		retval = 0;
 
 		/* FIXME use these NDIS_PACKET_TYPE_* bitflags to
-		 * filter packets in hard_start_xmit()
+		 * set the cdc_filter; it's not RNDIS-specific
 		 * NDIS_PACKET_TYPE_x == USB_CDC_PACKET_TYPE_x for x in:
 		 *	PROMISCUOUS, DIRECTED,
 		 *	MULTICAST, ALL_MULTICAST, BROADCAST
@@ -1194,10 +1195,10 @@ void rndis_add_hdr (struct sk_buff *skb)
 		return;
 	header = (void *) skb_push (skb, sizeof *header);
 	memset (header, 0, sizeof *header);
-	header->MessageType = __constant_cpu_to_le32 (1);
+	header->MessageType = __constant_cpu_to_le32(REMOTE_NDIS_PACKET_MSG);
 	header->MessageLength = cpu_to_le32(skb->len);
 	header->DataOffset = __constant_cpu_to_le32 (36);
-	header->OOBDataOffset = cpu_to_le32(skb->len - 44);
+	header->DataLength = cpu_to_le32(skb->len - sizeof *header);
 }
 
 void rndis_free_response (int configNr, u8 *buf)
@@ -1253,25 +1254,22 @@ static rndis_resp_t *rndis_add_response (int configNr, u32 length)
 	return r;
 }
 
-int rndis_rm_hdr (u8 *buf, u32 *length)
+int rndis_rm_hdr(struct sk_buff *skb)
 {
-	u32 i, messageLen, dataOffset;
-	__le32 *tmp;
-	
-	tmp = (__le32 *) buf; 
-
-	if (!buf || !length) return -1;
-	if (le32_to_cpup(tmp++) != 1) return -1;
-	
-	messageLen = le32_to_cpup(tmp++);
-	dataOffset = le32_to_cpup(tmp++) + 8;
-
-	if (messageLen < dataOffset || messageLen > *length) return -1;
-	
-	for (i = dataOffset; i < messageLen; i++)
-		buf [i - dataOffset] = buf [i];
-		
-	*length = messageLen - dataOffset;
+	/* tmp points to a struct rndis_packet_msg_type */
+	__le32		*tmp = (void *) skb->data;
+
+	/* MessageType, MessageLength */
+	if (__constant_cpu_to_le32(REMOTE_NDIS_PACKET_MSG)
+			!= get_unaligned(tmp++))
+		return -EINVAL;
+	tmp++;
+
+	/* DataOffset, DataLength */
+	if (!skb_pull(skb, le32_to_cpu(get_unaligned(tmp++))
+			+ 8 /* offset of DataOffset */))
+		return -EOVERFLOW;
+	skb_trim(skb, le32_to_cpu(get_unaligned(tmp++)));
 
 	return 0;
 }

drivers/usb/gadget/rndis.h

@@ -38,6 +38,7 @@
  */
 
 /* Message Set for Connectionless (802.3) Devices */
+#define REMOTE_NDIS_PACKET_MSG		0x00000001U
 #define REMOTE_NDIS_INITIALIZE_MSG	0x00000002U	/* Initialize device */
 #define REMOTE_NDIS_HALT_MSG		0x00000003U
 #define REMOTE_NDIS_QUERY_MSG		0x00000004U
@@ -333,7 +334,7 @@ int  rndis_set_param_vendor (u8 configNr, u32 vendorID,
 			    const char *vendorDescr);
 int  rndis_set_param_medium (u8 configNr, u32 medium, u32 speed);
 void rndis_add_hdr (struct sk_buff *skb);
-int  rndis_rm_hdr (u8 *buf, u32 *length);
+int rndis_rm_hdr (struct sk_buff *skb);
 u8   *rndis_get_next_response (int configNr, u32 *length);
 void rndis_free_response (int configNr, u8 *buf);