tools/testing/selftests/bpf/progs/bpf_smc.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/bpf_smc.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/progs/bpf_smc.c
Extension
.c
Size
3268 bytes
Lines
142
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct smc_sock___local {
	struct sock sk;
	struct smc_sock *listen_smc;
	bool use_fallback;
} __attribute__((preserve_access_index));

struct smc_hs_ctrl___local {
	char name[SMC_HS_CTRL_NAME_MAX];
	int (*syn_option)(struct tcp_sock *);
	int (*synack_option)(const struct tcp_sock  *, struct inet_request_sock *);
} __attribute__((preserve_access_index));

struct netns_smc___local {
	struct smc_hs_ctrl___local *hs_ctrl;
} __attribute__((preserve_access_index));

struct net___local {
	struct netns_smc___local smc;
} __attribute__((preserve_access_index));

int smc_cnt = 0;
int fallback_cnt = 0;

SEC("fentry/smc_release")
int BPF_PROG(bpf_smc_release, struct socket *sock)
{
	/* only count from one side (client) */
	if (sock->sk->__sk_common.skc_state == BPF_SMC_LISTEN)
		return 0;
	smc_cnt++;
	return 0;
}

SEC("fentry/smc_switch_to_fallback")
int BPF_PROG(bpf_smc_switch_to_fallback, struct smc_sock___local *smc)
{
	/* only count from one side (client) */
	if (smc && !smc->listen_smc)
		fallback_cnt++;
	return 0;
}

/* go with default value if no strat was found */
bool default_ip_strat_value = true;

struct smc_policy_ip_key {
	__u32	sip;
	__u32	dip;
};

struct smc_policy_ip_value {
	__u8	mode;
};

struct {
	__uint(type, BPF_MAP_TYPE_HASH);
	__uint(key_size, sizeof(struct smc_policy_ip_key));
	__uint(value_size, sizeof(struct smc_policy_ip_value));
	__uint(max_entries, 128);
	__uint(map_flags, BPF_F_NO_PREALLOC);
} smc_policy_ip SEC(".maps");

static bool smc_check(__u32 src, __u32 dst)
{
	struct smc_policy_ip_value *value;
	struct smc_policy_ip_key key = {
		.sip = src,
		.dip = dst,
	};

	value = bpf_map_lookup_elem(&smc_policy_ip, &key);
	return value ? value->mode : default_ip_strat_value;
}

SEC("fmod_ret/update_socket_protocol")
int BPF_PROG(smc_run, int family, int type, int protocol)
{
	struct task_struct *task;

	if (family != AF_INET && family != AF_INET6)
		return protocol;

	if ((type & 0xf) != SOCK_STREAM)
		return protocol;

	if (protocol != 0 && protocol != IPPROTO_TCP)
		return protocol;

	task = bpf_get_current_task_btf();
	/* Prevent from affecting other tests */

Annotation

Implementation Notes