mirror-linux/net/smc/smc_hs_bpf.c

141 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* Generic hook for SMC handshake flow.
*
* Copyright IBM Corp. 2016
* Copyright (c) 2025, Alibaba Inc.
*
* Author: D. Wythe <alibuda@linux.alibaba.com>
*/
#include <linux/bpf_verifier.h>
#include <linux/bpf.h>
#include <linux/btf.h>
#include <linux/rculist.h>
#include "smc_hs_bpf.h"
static DEFINE_SPINLOCK(smc_hs_ctrl_list_lock);
static LIST_HEAD(smc_hs_ctrl_list);
static int smc_hs_ctrl_reg(struct smc_hs_ctrl *ctrl)
{
int ret = 0;
spin_lock(&smc_hs_ctrl_list_lock);
/* already exist or duplicate name */
if (smc_hs_ctrl_find_by_name(ctrl->name))
ret = -EEXIST;
else
list_add_tail_rcu(&ctrl->list, &smc_hs_ctrl_list);
spin_unlock(&smc_hs_ctrl_list_lock);
return ret;
}
static void smc_hs_ctrl_unreg(struct smc_hs_ctrl *ctrl)
{
spin_lock(&smc_hs_ctrl_list_lock);
list_del_rcu(&ctrl->list);
spin_unlock(&smc_hs_ctrl_list_lock);
/* Ensure that all readers to complete */
synchronize_rcu();
}
struct smc_hs_ctrl *smc_hs_ctrl_find_by_name(const char *name)
{
struct smc_hs_ctrl *ctrl;
list_for_each_entry_rcu(ctrl, &smc_hs_ctrl_list, list) {
if (strcmp(ctrl->name, name) == 0)
return ctrl;
}
return NULL;
}
static int __smc_bpf_stub_set_tcp_option(struct tcp_sock *tp) { return 1; }
static int __smc_bpf_stub_set_tcp_option_cond(const struct tcp_sock *tp,
struct inet_request_sock *ireq)
{
return 1;
}
static struct smc_hs_ctrl __smc_bpf_hs_ctrl = {
.syn_option = __smc_bpf_stub_set_tcp_option,
.synack_option = __smc_bpf_stub_set_tcp_option_cond,
};
static int smc_bpf_hs_ctrl_init(struct btf *btf) { return 0; }
static int smc_bpf_hs_ctrl_reg(void *kdata, struct bpf_link *link)
{
if (link)
return -EOPNOTSUPP;
return smc_hs_ctrl_reg(kdata);
}
static void smc_bpf_hs_ctrl_unreg(void *kdata, struct bpf_link *link)
{
smc_hs_ctrl_unreg(kdata);
}
static int smc_bpf_hs_ctrl_init_member(const struct btf_type *t,
const struct btf_member *member,
void *kdata, const void *udata)
{
const struct smc_hs_ctrl *u_ctrl;
struct smc_hs_ctrl *k_ctrl;
u32 moff;
u_ctrl = (const struct smc_hs_ctrl *)udata;
k_ctrl = (struct smc_hs_ctrl *)kdata;
moff = __btf_member_bit_offset(t, member) / 8;
switch (moff) {
case offsetof(struct smc_hs_ctrl, name):
if (bpf_obj_name_cpy(k_ctrl->name, u_ctrl->name,
sizeof(u_ctrl->name)) <= 0)
return -EINVAL;
return 1;
case offsetof(struct smc_hs_ctrl, flags):
if (u_ctrl->flags & ~SMC_HS_CTRL_ALL_FLAGS)
return -EINVAL;
k_ctrl->flags = u_ctrl->flags;
return 1;
default:
break;
}
return 0;
}
static const struct bpf_func_proto *
bpf_smc_hs_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
return bpf_base_func_proto(func_id, prog);
}
static const struct bpf_verifier_ops smc_bpf_verifier_ops = {
.get_func_proto = bpf_smc_hs_func_proto,
.is_valid_access = bpf_tracing_btf_ctx_access,
};
static struct bpf_struct_ops bpf_smc_hs_ctrl_ops = {
.name = "smc_hs_ctrl",
.init = smc_bpf_hs_ctrl_init,
.reg = smc_bpf_hs_ctrl_reg,
.unreg = smc_bpf_hs_ctrl_unreg,
.cfi_stubs = &__smc_bpf_hs_ctrl,
.verifier_ops = &smc_bpf_verifier_ops,
.init_member = smc_bpf_hs_ctrl_init_member,
.owner = THIS_MODULE,
};
int bpf_smc_hs_ctrl_init(void)
{
return register_bpf_struct_ops(&bpf_smc_hs_ctrl_ops, smc_hs_ctrl);
}