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// 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";
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