1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
3 #define BPF_NO_KFUNC_PROTOTYPES
4 #include <vmlinux.h>
5 #include <bpf/bpf_helpers.h>
6 #include <bpf/bpf_tracing.h>
7 #include <bpf/bpf_core_read.h>
8 #include "bpf_experimental.h"
9
10 struct {
11 __uint(type, BPF_MAP_TYPE_ARENA);
12 __uint(map_flags, BPF_F_MMAPABLE);
13 __uint(max_entries, 100); /* number of pages */
14 } arena SEC(".maps");
15
16 #include "bpf_arena_htab.h"
17
18 void __arena *htab_for_user;
19 bool skip = false;
20
21 int zero = 0;
22 char __arena arr1[100000];
23 char arr2[1000];
24
25 SEC("syscall")
26 int arena_htab_llvm(void *ctx)
27 {
28 #if defined(__BPF_FEATURE_ADDR_SPACE_CAST) || defined(BPF_ARENA_FORCE_ASM)
29 struct htab __arena *htab;
30 char __arena *arr = arr1;
31 __u64 i;
32
33 htab = bpf_alloc(sizeof(*htab));
34 cast_kern(htab);
35 htab_init(htab);
36
37 cast_kern(arr);
38
39 /* first run. No old elems in the table */
40 for (i = zero; i < 100000 && can_loop; i++) {
41 htab_update_elem(htab, i, i);
42 arr[i] = i;
43 }
44
45 /* should replace some elems with new ones */
46 for (i = zero; i < 1000 && can_loop; i++) {
47 htab_update_elem(htab, i, i);
48 /* Access mem to make the verifier use bounded loop logic */
49 arr2[i] = i;
50 }
51 cast_user(htab);
52 htab_for_user = htab;
53 #else
54 skip = true;
55 #endif
56 return 0;
57 }
58
59 char _license[] SEC("license") = "GPL";
60
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