1 /* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
2 /* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
3 #pragma once
4
5 #ifndef WRITE_ONCE
6 #define WRITE_ONCE(x, val) ((*(volatile typeof(x) *) &(x)) = (val))
7 #endif
8
9 #ifndef NUMA_NO_NODE
10 #define NUMA_NO_NODE (-1)
11 #endif
12
13 #ifndef arena_container_of
14 #define arena_container_of(ptr, type, member) \
15 ({ \
16 void __arena *__mptr = (void __arena *)(ptr); \
17 ((type *)(__mptr - offsetof(type, member))); \
18 })
19 #endif
20
21 #ifdef __BPF__ /* when compiled as bpf program */
22
23 #ifndef PAGE_SIZE
24 #define PAGE_SIZE __PAGE_SIZE
25 /*
26 * for older kernels try sizeof(struct genradix_node)
27 * or flexible:
28 * static inline long __bpf_page_size(void) {
29 * return bpf_core_enum_value(enum page_size_enum___l, __PAGE_SIZE___l) ?: sizeof(struct genradix_node);
30 * }
31 * but generated code is not great.
32 */
33 #endif
34
35 #if defined(__BPF_FEATURE_ADDR_SPACE_CAST) && !defined(BPF_ARENA_FORCE_ASM)
36 #define __arena __attribute__((address_space(1)))
37 #define __arena_global __attribute__((address_space(1)))
38 #define cast_kern(ptr) /* nop for bpf prog. emitted by LLVM */
39 #define cast_user(ptr) /* nop for bpf prog. emitted by LLVM */
40 #else
41 #define __arena
42 #define __arena_global SEC(".addr_space.1")
43 #define cast_kern(ptr) bpf_addr_space_cast(ptr, 0, 1)
44 #define cast_user(ptr) bpf_addr_space_cast(ptr, 1, 0)
45 #endif
46
47 void __arena* bpf_arena_alloc_pages(void *map, void __arena *addr, __u32 page_cnt,
48 int node_id, __u64 flags) __ksym __weak;
49 void bpf_arena_free_pages(void *map, void __arena *ptr, __u32 page_cnt) __ksym __weak;
50
51 #else /* when compiled as user space code */
52
53 #define __arena
54 #define __arg_arena
55 #define cast_kern(ptr) /* nop for user space */
56 #define cast_user(ptr) /* nop for user space */
57 __weak char arena[1];
58
59 #ifndef offsetof
60 #define offsetof(type, member) ((unsigned long)&((type *)0)->member)
61 #endif
62
bpf_arena_alloc_pages(void * map,void * addr,__u32 page_cnt,int node_id,__u64 flags)63 static inline void __arena* bpf_arena_alloc_pages(void *map, void *addr, __u32 page_cnt,
64 int node_id, __u64 flags)
65 {
66 return NULL;
67 }
bpf_arena_free_pages(void * map,void __arena * ptr,__u32 page_cnt)68 static inline void bpf_arena_free_pages(void *map, void __arena *ptr, __u32 page_cnt)
69 {
70 }
71
72 #endif
73