drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c

Source file repositories/reference/linux-study-clean/drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c

File Facts

System
Linux kernel
Corpus path
drivers/net/ethernet/chelsio/libcxgb/libcxgb_cm.c
Extension
.c
Size
4765 bytes
Lines
149
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: exported/initcall integration point
Status
integration 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

#include <linux/tcp.h>
#include <linux/ipv6.h>
#include <net/inet_ecn.h>
#include <net/route.h>
#include <net/ip6_route.h>

#include "libcxgb_cm.h"

void
cxgb_get_4tuple(struct cpl_pass_accept_req *req, enum chip_type type,
		int *iptype, __u8 *local_ip, __u8 *peer_ip,
		__be16 *local_port, __be16 *peer_port)
{
	int eth_len = (CHELSIO_CHIP_VERSION(type) <= CHELSIO_T5) ?
		      ETH_HDR_LEN_G(be32_to_cpu(req->hdr_len)) :
		      T6_ETH_HDR_LEN_G(be32_to_cpu(req->hdr_len));
	int ip_len = (CHELSIO_CHIP_VERSION(type) <= CHELSIO_T5) ?
		     IP_HDR_LEN_G(be32_to_cpu(req->hdr_len)) :
		     T6_IP_HDR_LEN_G(be32_to_cpu(req->hdr_len));
	struct iphdr *ip = (struct iphdr *)((u8 *)(req + 1) + eth_len);
	struct ipv6hdr *ip6 = (struct ipv6hdr *)((u8 *)(req + 1) + eth_len);
	struct tcphdr *tcp = (struct tcphdr *)
			     ((u8 *)(req + 1) + eth_len + ip_len);

	if (ip->version == 4) {
		pr_debug("%s saddr 0x%x daddr 0x%x sport %u dport %u\n",
			 __func__, ntohl(ip->saddr), ntohl(ip->daddr),
			 ntohs(tcp->source), ntohs(tcp->dest));
		*iptype = 4;
		memcpy(peer_ip, &ip->saddr, 4);
		memcpy(local_ip, &ip->daddr, 4);
	} else {
		pr_debug("%s saddr %pI6 daddr %pI6 sport %u dport %u\n",
			 __func__, ip6->saddr.s6_addr, ip6->daddr.s6_addr,
			 ntohs(tcp->source), ntohs(tcp->dest));
		*iptype = 6;
		memcpy(peer_ip, ip6->saddr.s6_addr, 16);
		memcpy(local_ip, ip6->daddr.s6_addr, 16);
	}
	*peer_port = tcp->source;
	*local_port = tcp->dest;
}
EXPORT_SYMBOL(cxgb_get_4tuple);

static bool
cxgb_our_interface(struct cxgb4_lld_info *lldi,
		   struct net_device *(*get_real_dev)(struct net_device *),
		   struct net_device *egress_dev)
{
	int i;

	egress_dev = get_real_dev(egress_dev);
	for (i = 0; i < lldi->nports; i++)
		if (lldi->ports[i] == egress_dev)
			return true;
	return false;
}

struct dst_entry *
cxgb_find_route(struct cxgb4_lld_info *lldi,
		struct net_device *(*get_real_dev)(struct net_device *),
		__be32 local_ip, __be32 peer_ip, __be16 local_port,
		__be16 peer_port, u8 tos)
{
	struct rtable *rt;
	struct flowi4 fl4;
	struct neighbour *n;

	rt = ip_route_output_ports(&init_net, &fl4, NULL, peer_ip, local_ip,
				   peer_port, local_port, IPPROTO_TCP,
				   tos & ~INET_ECN_MASK, 0);
	if (IS_ERR(rt))
		return NULL;
	n = dst_neigh_lookup(&rt->dst, &peer_ip);
	if (!n)
		return NULL;
	if (!cxgb_our_interface(lldi, get_real_dev, n->dev) &&
	    !(n->dev->flags & IFF_LOOPBACK)) {
		neigh_release(n);
		dst_release(&rt->dst);
		return NULL;
	}
	neigh_release(n);
	return &rt->dst;
}
EXPORT_SYMBOL(cxgb_find_route);

struct dst_entry *
cxgb_find_route6(struct cxgb4_lld_info *lldi,
		 struct net_device *(*get_real_dev)(struct net_device *),

Annotation

Implementation Notes