drivers/net/wireless/marvell/mwifiex/sta_rx.c

Source file repositories/reference/linux-study-clean/drivers/net/wireless/marvell/mwifiex/sta_rx.c

File Facts

System
Linux kernel
Corpus path
drivers/net/wireless/marvell/mwifiex/sta_rx.c
Extension
.c
Size
8570 bytes
Lines
272
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (NDISC_NEIGHBOUR_ADVERTISEMENT == icmpv6->icmp6_type) {
			if (!memcmp(&ipv6->saddr, &ipv6->daddr,
				    sizeof(struct in6_addr)))
				return true;
		}
		break;
	default:
		break;
	}

	return false;
}

/*
 * This function processes the received packet and forwards it
 * to kernel/upper layer.
 *
 * This function parses through the received packet and determines
 * if it is a debug packet or normal packet.
 *
 * For non-debug packets, the function chops off unnecessary leading
 * header bytes, reconstructs the packet as an ethernet frame or
 * 802.2/llc/snap frame as required, and sends it to kernel/upper layer.
 *
 * The completion callback is called after processing in complete.
 */
int mwifiex_process_rx_packet(struct mwifiex_private *priv,
			      struct sk_buff *skb)
{
	int ret;
	struct rx_packet_hdr *rx_pkt_hdr;
	struct rxpd *local_rx_pd;
	int hdr_chop;
	struct ethhdr *eth;
	u16 rx_pkt_off, rx_pkt_len;
	u8 *offset;
	u8 adj_rx_rate = 0;

	local_rx_pd = (struct rxpd *) (skb->data);

	rx_pkt_off = le16_to_cpu(local_rx_pd->rx_pkt_offset);
	rx_pkt_len = le16_to_cpu(local_rx_pd->rx_pkt_length);
	rx_pkt_hdr = (void *)local_rx_pd + rx_pkt_off;

	if (sizeof(rx_pkt_hdr->eth803_hdr) + sizeof(rfc1042_header) +
	    rx_pkt_off > skb->len) {
		mwifiex_dbg(priv->adapter, ERROR,
			    "wrong rx packet offset: len=%d, rx_pkt_off=%d\n",
			    skb->len, rx_pkt_off);
		priv->stats.rx_dropped++;
		dev_kfree_skb_any(skb);
		return -1;
	}

	if (sizeof(*rx_pkt_hdr) + rx_pkt_off <= skb->len &&
	    ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
		      sizeof(bridge_tunnel_header))) ||
	     (!memcmp(&rx_pkt_hdr->rfc1042_hdr, rfc1042_header,
		      sizeof(rfc1042_header)) &&
	      ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_AARP &&
	      ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_IPX))) {
		/*
		 *  Replace the 803 header and rfc1042 header (llc/snap) with an
		 *    EthernetII header, keep the src/dst and snap_type
		 *    (ethertype).
		 *  The firmware only passes up SNAP frames converting
		 *    all RX Data from 802.11 to 802.2/LLC/SNAP frames.
		 *  To create the Ethernet II, just move the src, dst address
		 *    right before the snap_type.
		 */
		eth = (struct ethhdr *)
			((u8 *) &rx_pkt_hdr->eth803_hdr
			 + sizeof(rx_pkt_hdr->eth803_hdr) +
			 sizeof(rx_pkt_hdr->rfc1042_hdr)
			 - sizeof(rx_pkt_hdr->eth803_hdr.h_dest)
			 - sizeof(rx_pkt_hdr->eth803_hdr.h_source)
			 - sizeof(rx_pkt_hdr->rfc1042_hdr.snap_type));

		memcpy(eth->h_source, rx_pkt_hdr->eth803_hdr.h_source,
		       sizeof(eth->h_source));
		memcpy(eth->h_dest, rx_pkt_hdr->eth803_hdr.h_dest,
		       sizeof(eth->h_dest));

		/* Chop off the rxpd + the excess memory from the 802.2/llc/snap
		   header that was removed. */
		hdr_chop = (u8 *) eth - (u8 *) local_rx_pd;
	} else {
		/* Chop off the rxpd */
		hdr_chop = (u8 *) &rx_pkt_hdr->eth803_hdr -
			(u8 *) local_rx_pd;

Annotation

Implementation Notes