108 lines
2.2 KiB
C
108 lines
2.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
|
|
|
|
#include <vmlinux.h>
|
|
#include <bpf/bpf_tracing.h>
|
|
#include <bpf/bpf_helpers.h>
|
|
#include <bpf/bpf_core_read.h>
|
|
#include "../bpf_experimental.h"
|
|
#include "../bpf_testmod/bpf_testmod_kfunc.h"
|
|
|
|
struct node_data {
|
|
long key;
|
|
long data;
|
|
struct bpf_rb_node node;
|
|
};
|
|
|
|
struct map_value {
|
|
struct prog_test_ref_kfunc *not_kptr;
|
|
struct prog_test_ref_kfunc __kptr *val;
|
|
struct node_data __kptr *node;
|
|
};
|
|
|
|
/* This is necessary so that LLVM generates BTF for node_data struct
|
|
* If it's not included, a fwd reference for node_data will be generated but
|
|
* no struct. Example BTF of "node" field in map_value when not included:
|
|
*
|
|
* [10] PTR '(anon)' type_id=35
|
|
* [34] FWD 'node_data' fwd_kind=struct
|
|
* [35] TYPE_TAG 'kptr_ref' type_id=34
|
|
*
|
|
* (with no node_data struct defined)
|
|
* Had to do the same w/ bpf_kfunc_call_test_release below
|
|
*/
|
|
struct node_data *just_here_because_btf_bug;
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_ARRAY);
|
|
__type(key, int);
|
|
__type(value, struct map_value);
|
|
__uint(max_entries, 2);
|
|
} some_nodes SEC(".maps");
|
|
|
|
static int create_and_stash(int idx, int val)
|
|
{
|
|
struct map_value *mapval;
|
|
struct node_data *res;
|
|
|
|
mapval = bpf_map_lookup_elem(&some_nodes, &idx);
|
|
if (!mapval)
|
|
return 1;
|
|
|
|
res = bpf_obj_new(typeof(*res));
|
|
if (!res)
|
|
return 1;
|
|
res->key = val;
|
|
|
|
res = bpf_kptr_xchg(&mapval->node, res);
|
|
if (res)
|
|
bpf_obj_drop(res);
|
|
return 0;
|
|
}
|
|
|
|
SEC("tc")
|
|
long stash_rb_nodes(void *ctx)
|
|
{
|
|
return create_and_stash(0, 41) ?: create_and_stash(1, 42);
|
|
}
|
|
|
|
SEC("tc")
|
|
long unstash_rb_node(void *ctx)
|
|
{
|
|
struct map_value *mapval;
|
|
struct node_data *res;
|
|
long retval;
|
|
int key = 1;
|
|
|
|
mapval = bpf_map_lookup_elem(&some_nodes, &key);
|
|
if (!mapval)
|
|
return 1;
|
|
|
|
res = bpf_kptr_xchg(&mapval->node, NULL);
|
|
if (res) {
|
|
retval = res->key;
|
|
bpf_obj_drop(res);
|
|
return retval;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
SEC("tc")
|
|
long stash_test_ref_kfunc(void *ctx)
|
|
{
|
|
struct prog_test_ref_kfunc *res;
|
|
struct map_value *mapval;
|
|
int key = 0;
|
|
|
|
mapval = bpf_map_lookup_elem(&some_nodes, &key);
|
|
if (!mapval)
|
|
return 1;
|
|
|
|
res = bpf_kptr_xchg(&mapval->val, NULL);
|
|
if (res)
|
|
bpf_kfunc_call_test_release(res);
|
|
return 0;
|
|
}
|
|
|
|
char _license[] SEC("license") = "GPL";
|