drivers/net/ethernet/sfc/tc_conntrack.c

Source file repositories/reference/linux-study-clean/drivers/net/ethernet/sfc/tc_conntrack.c

File Facts

System
Linux kernel
Corpus path
drivers/net/ethernet/sfc/tc_conntrack.c
Extension
.c
Size
17334 bytes
Lines
626
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

struct efx_tc_ct_mangler_state {
	u8 ipv4:1;
	u8 tcpudp:1;
};

static int efx_tc_ct_mangle(struct efx_nic *efx, struct efx_tc_ct_entry *conn,
			    const struct flow_action_entry *fa,
			    struct efx_tc_ct_mangler_state *mung)
{
	/* Is this the first mangle we've processed for this rule? */
	bool first = !(mung->ipv4 || mung->tcpudp);
	bool dnat = false;

	switch (fa->mangle.htype) {
	case FLOW_ACT_MANGLE_HDR_TYPE_IP4:
		switch (fa->mangle.offset) {
		case offsetof(struct iphdr, daddr):
			dnat = true;
			fallthrough;
		case offsetof(struct iphdr, saddr):
			if (fa->mangle.mask)
				return -EOPNOTSUPP;
			conn->nat_ip = htonl(fa->mangle.val);
			mung->ipv4 = 1;
			break;
		default:
			return -EOPNOTSUPP;
		}
		break;
	case FLOW_ACT_MANGLE_HDR_TYPE_TCP:
	case FLOW_ACT_MANGLE_HDR_TYPE_UDP:
		/* Both struct tcphdr and struct udphdr start with
		 *	__be16 source;
		 *	__be16 dest;
		 * so we can use the same code for both.
		 */
		switch (fa->mangle.offset) {
		case offsetof(struct tcphdr, dest):
			BUILD_BUG_ON(offsetof(struct tcphdr, dest) !=
				     offsetof(struct udphdr, dest));
			dnat = true;
			fallthrough;
		case offsetof(struct tcphdr, source):
			BUILD_BUG_ON(offsetof(struct tcphdr, source) !=
				     offsetof(struct udphdr, source));
			if (~fa->mangle.mask != 0xffff)
				return -EOPNOTSUPP;
			conn->l4_natport = htons(fa->mangle.val);
			mung->tcpudp = 1;
			break;
		default:
			return -EOPNOTSUPP;
		}
		break;
	default:
		return -EOPNOTSUPP;
	}
	/* first mangle tells us whether this is SNAT or DNAT;
	 * subsequent mangles must match that
	 */
	if (first)
		conn->dnat = dnat;
	else if (conn->dnat != dnat)
		return -EOPNOTSUPP;
	return 0;
}

static int efx_tc_ct_replace(struct efx_tc_ct_zone *ct_zone,
			     struct flow_cls_offload *tc)
{
	struct flow_rule *fr = flow_cls_offload_flow_rule(tc);
	struct efx_tc_ct_mangler_state mung = {};
	struct efx_tc_ct_entry *conn, *old;
	struct efx_nic *efx = ct_zone->efx;
	const struct flow_action_entry *fa;
	struct efx_tc_counter *cnt;
	int rc, i;

	if (WARN_ON(!efx->tc))
		return -ENETDOWN;
	if (WARN_ON(!efx->tc->up))
		return -ENETDOWN;

	conn = kzalloc_obj(*conn, GFP_USER);
	if (!conn)
		return -ENOMEM;
	conn->cookie = tc->cookie;
	old = rhashtable_lookup_get_insert_fast(&efx->tc->ct_ht,
						&conn->linkage,
						efx_tc_ct_ht_params);

Annotation

Implementation Notes