128fbcfa0SAlexei Starovoitov /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 281ed18abSAlexei Starovoitov * Copyright (c) 2016,2017 Facebook 328fbcfa0SAlexei Starovoitov * 428fbcfa0SAlexei Starovoitov * This program is free software; you can redistribute it and/or 528fbcfa0SAlexei Starovoitov * modify it under the terms of version 2 of the GNU General Public 628fbcfa0SAlexei Starovoitov * License as published by the Free Software Foundation. 728fbcfa0SAlexei Starovoitov * 828fbcfa0SAlexei Starovoitov * This program is distributed in the hope that it will be useful, but 928fbcfa0SAlexei Starovoitov * WITHOUT ANY WARRANTY; without even the implied warranty of 1028fbcfa0SAlexei Starovoitov * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 1128fbcfa0SAlexei Starovoitov * General Public License for more details. 1228fbcfa0SAlexei Starovoitov */ 1328fbcfa0SAlexei Starovoitov #include <linux/bpf.h> 14a26ca7c9SMartin KaFai Lau #include <linux/btf.h> 1528fbcfa0SAlexei Starovoitov #include <linux/err.h> 1628fbcfa0SAlexei Starovoitov #include <linux/slab.h> 1728fbcfa0SAlexei Starovoitov #include <linux/mm.h> 1804fd61abSAlexei Starovoitov #include <linux/filter.h> 190cdf5640SDaniel Borkmann #include <linux/perf_event.h> 20a26ca7c9SMartin KaFai Lau #include <uapi/linux/btf.h> 2128fbcfa0SAlexei Starovoitov 2256f668dfSMartin KaFai Lau #include "map_in_map.h" 2356f668dfSMartin KaFai Lau 246e71b04aSChenbo Feng #define ARRAY_CREATE_FLAG_MASK \ 256e71b04aSChenbo Feng (BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY) 266e71b04aSChenbo Feng 27a10423b8SAlexei Starovoitov static void bpf_array_free_percpu(struct bpf_array *array) 28a10423b8SAlexei Starovoitov { 29a10423b8SAlexei Starovoitov int i; 30a10423b8SAlexei Starovoitov 3132fff239SEric Dumazet for (i = 0; i < array->map.max_entries; i++) { 32a10423b8SAlexei Starovoitov free_percpu(array->pptrs[i]); 3332fff239SEric Dumazet cond_resched(); 3432fff239SEric Dumazet } 35a10423b8SAlexei Starovoitov } 36a10423b8SAlexei Starovoitov 37a10423b8SAlexei Starovoitov static int bpf_array_alloc_percpu(struct bpf_array *array) 38a10423b8SAlexei Starovoitov { 39a10423b8SAlexei Starovoitov void __percpu *ptr; 40a10423b8SAlexei Starovoitov int i; 41a10423b8SAlexei Starovoitov 42a10423b8SAlexei Starovoitov for (i = 0; i < array->map.max_entries; i++) { 43a10423b8SAlexei Starovoitov ptr = __alloc_percpu_gfp(array->elem_size, 8, 44a10423b8SAlexei Starovoitov GFP_USER | __GFP_NOWARN); 45a10423b8SAlexei Starovoitov if (!ptr) { 46a10423b8SAlexei Starovoitov bpf_array_free_percpu(array); 47a10423b8SAlexei Starovoitov return -ENOMEM; 48a10423b8SAlexei Starovoitov } 49a10423b8SAlexei Starovoitov array->pptrs[i] = ptr; 5032fff239SEric Dumazet cond_resched(); 51a10423b8SAlexei Starovoitov } 52a10423b8SAlexei Starovoitov 53a10423b8SAlexei Starovoitov return 0; 54a10423b8SAlexei Starovoitov } 55a10423b8SAlexei Starovoitov 5628fbcfa0SAlexei Starovoitov /* Called from syscall */ 575dc4c4b7SMartin KaFai Lau int array_map_alloc_check(union bpf_attr *attr) 58ad46061fSJakub Kicinski { 59ad46061fSJakub Kicinski bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; 60ad46061fSJakub Kicinski int numa_node = bpf_map_attr_numa_node(attr); 61ad46061fSJakub Kicinski 62ad46061fSJakub Kicinski /* check sanity of attributes */ 63ad46061fSJakub Kicinski if (attr->max_entries == 0 || attr->key_size != 4 || 64ad46061fSJakub Kicinski attr->value_size == 0 || 65ad46061fSJakub Kicinski attr->map_flags & ~ARRAY_CREATE_FLAG_MASK || 66ad46061fSJakub Kicinski (percpu && numa_node != NUMA_NO_NODE)) 67ad46061fSJakub Kicinski return -EINVAL; 68ad46061fSJakub Kicinski 69ad46061fSJakub Kicinski if (attr->value_size > KMALLOC_MAX_SIZE) 70ad46061fSJakub Kicinski /* if value_size is bigger, the user space won't be able to 71ad46061fSJakub Kicinski * access the elements. 72ad46061fSJakub Kicinski */ 73ad46061fSJakub Kicinski return -E2BIG; 74ad46061fSJakub Kicinski 75ad46061fSJakub Kicinski return 0; 76ad46061fSJakub Kicinski } 77ad46061fSJakub Kicinski 7828fbcfa0SAlexei Starovoitov static struct bpf_map *array_map_alloc(union bpf_attr *attr) 7928fbcfa0SAlexei Starovoitov { 80a10423b8SAlexei Starovoitov bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; 819c2d63b8SDaniel Borkmann int ret, numa_node = bpf_map_attr_numa_node(attr); 82b2157399SAlexei Starovoitov u32 elem_size, index_mask, max_entries; 83b2157399SAlexei Starovoitov bool unpriv = !capable(CAP_SYS_ADMIN); 849c2d63b8SDaniel Borkmann u64 cost, array_size, mask64; 8528fbcfa0SAlexei Starovoitov struct bpf_array *array; 8628fbcfa0SAlexei Starovoitov 8728fbcfa0SAlexei Starovoitov elem_size = round_up(attr->value_size, 8); 8828fbcfa0SAlexei Starovoitov 89b2157399SAlexei Starovoitov max_entries = attr->max_entries; 90b2157399SAlexei Starovoitov 91bbeb6e43SDaniel Borkmann /* On 32 bit archs roundup_pow_of_two() with max_entries that has 92bbeb6e43SDaniel Borkmann * upper most bit set in u32 space is undefined behavior due to 93bbeb6e43SDaniel Borkmann * resulting 1U << 32, so do it manually here in u64 space. 94bbeb6e43SDaniel Borkmann */ 95bbeb6e43SDaniel Borkmann mask64 = fls_long(max_entries - 1); 96bbeb6e43SDaniel Borkmann mask64 = 1ULL << mask64; 97bbeb6e43SDaniel Borkmann mask64 -= 1; 98bbeb6e43SDaniel Borkmann 99bbeb6e43SDaniel Borkmann index_mask = mask64; 100bbeb6e43SDaniel Borkmann if (unpriv) { 101b2157399SAlexei Starovoitov /* round up array size to nearest power of 2, 102b2157399SAlexei Starovoitov * since cpu will speculate within index_mask limits 103b2157399SAlexei Starovoitov */ 104b2157399SAlexei Starovoitov max_entries = index_mask + 1; 105bbeb6e43SDaniel Borkmann /* Check for overflows. */ 106bbeb6e43SDaniel Borkmann if (max_entries < attr->max_entries) 107bbeb6e43SDaniel Borkmann return ERR_PTR(-E2BIG); 108bbeb6e43SDaniel Borkmann } 109b2157399SAlexei Starovoitov 110a10423b8SAlexei Starovoitov array_size = sizeof(*array); 111a10423b8SAlexei Starovoitov if (percpu) 112b2157399SAlexei Starovoitov array_size += (u64) max_entries * sizeof(void *); 113a10423b8SAlexei Starovoitov else 114b2157399SAlexei Starovoitov array_size += (u64) max_entries * elem_size; 115a10423b8SAlexei Starovoitov 116a10423b8SAlexei Starovoitov /* make sure there is no u32 overflow later in round_up() */ 1179c2d63b8SDaniel Borkmann cost = array_size; 1189c2d63b8SDaniel Borkmann if (cost >= U32_MAX - PAGE_SIZE) 119daaf427cSAlexei Starovoitov return ERR_PTR(-ENOMEM); 1209c2d63b8SDaniel Borkmann if (percpu) { 1219c2d63b8SDaniel Borkmann cost += (u64)attr->max_entries * elem_size * num_possible_cpus(); 1229c2d63b8SDaniel Borkmann if (cost >= U32_MAX - PAGE_SIZE) 1239c2d63b8SDaniel Borkmann return ERR_PTR(-ENOMEM); 1249c2d63b8SDaniel Borkmann } 1259c2d63b8SDaniel Borkmann cost = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT; 1269c2d63b8SDaniel Borkmann 1279c2d63b8SDaniel Borkmann ret = bpf_map_precharge_memlock(cost); 1289c2d63b8SDaniel Borkmann if (ret < 0) 1299c2d63b8SDaniel Borkmann return ERR_PTR(ret); 130daaf427cSAlexei Starovoitov 13128fbcfa0SAlexei Starovoitov /* allocate all map elements and zero-initialize them */ 13296eabe7aSMartin KaFai Lau array = bpf_map_area_alloc(array_size, numa_node); 13328fbcfa0SAlexei Starovoitov if (!array) 13428fbcfa0SAlexei Starovoitov return ERR_PTR(-ENOMEM); 135b2157399SAlexei Starovoitov array->index_mask = index_mask; 136b2157399SAlexei Starovoitov array->map.unpriv_array = unpriv; 13728fbcfa0SAlexei Starovoitov 13828fbcfa0SAlexei Starovoitov /* copy mandatory map attributes */ 13932852649SJakub Kicinski bpf_map_init_from_attr(&array->map, attr); 1409c2d63b8SDaniel Borkmann array->map.pages = cost; 14128fbcfa0SAlexei Starovoitov array->elem_size = elem_size; 14228fbcfa0SAlexei Starovoitov 1439c2d63b8SDaniel Borkmann if (percpu && bpf_array_alloc_percpu(array)) { 144d407bd25SDaniel Borkmann bpf_map_area_free(array); 145a10423b8SAlexei Starovoitov return ERR_PTR(-ENOMEM); 146a10423b8SAlexei Starovoitov } 147a10423b8SAlexei Starovoitov 14828fbcfa0SAlexei Starovoitov return &array->map; 14928fbcfa0SAlexei Starovoitov } 15028fbcfa0SAlexei Starovoitov 15128fbcfa0SAlexei Starovoitov /* Called from syscall or from eBPF program */ 15228fbcfa0SAlexei Starovoitov static void *array_map_lookup_elem(struct bpf_map *map, void *key) 15328fbcfa0SAlexei Starovoitov { 15428fbcfa0SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 15528fbcfa0SAlexei Starovoitov u32 index = *(u32 *)key; 15628fbcfa0SAlexei Starovoitov 157a10423b8SAlexei Starovoitov if (unlikely(index >= array->map.max_entries)) 15828fbcfa0SAlexei Starovoitov return NULL; 15928fbcfa0SAlexei Starovoitov 160b2157399SAlexei Starovoitov return array->value + array->elem_size * (index & array->index_mask); 16128fbcfa0SAlexei Starovoitov } 16228fbcfa0SAlexei Starovoitov 16381ed18abSAlexei Starovoitov /* emit BPF instructions equivalent to C code of array_map_lookup_elem() */ 16481ed18abSAlexei Starovoitov static u32 array_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf) 16581ed18abSAlexei Starovoitov { 166b2157399SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 16781ed18abSAlexei Starovoitov struct bpf_insn *insn = insn_buf; 168fad73a1aSMartin KaFai Lau u32 elem_size = round_up(map->value_size, 8); 16981ed18abSAlexei Starovoitov const int ret = BPF_REG_0; 17081ed18abSAlexei Starovoitov const int map_ptr = BPF_REG_1; 17181ed18abSAlexei Starovoitov const int index = BPF_REG_2; 17281ed18abSAlexei Starovoitov 17381ed18abSAlexei Starovoitov *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value)); 17481ed18abSAlexei Starovoitov *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0); 175b2157399SAlexei Starovoitov if (map->unpriv_array) { 176b2157399SAlexei Starovoitov *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 4); 177b2157399SAlexei Starovoitov *insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask); 178b2157399SAlexei Starovoitov } else { 179fad73a1aSMartin KaFai Lau *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 3); 180b2157399SAlexei Starovoitov } 181fad73a1aSMartin KaFai Lau 182fad73a1aSMartin KaFai Lau if (is_power_of_2(elem_size)) { 18381ed18abSAlexei Starovoitov *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size)); 18481ed18abSAlexei Starovoitov } else { 18581ed18abSAlexei Starovoitov *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size); 18681ed18abSAlexei Starovoitov } 18781ed18abSAlexei Starovoitov *insn++ = BPF_ALU64_REG(BPF_ADD, ret, map_ptr); 18881ed18abSAlexei Starovoitov *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1); 18981ed18abSAlexei Starovoitov *insn++ = BPF_MOV64_IMM(ret, 0); 19081ed18abSAlexei Starovoitov return insn - insn_buf; 19181ed18abSAlexei Starovoitov } 19281ed18abSAlexei Starovoitov 193a10423b8SAlexei Starovoitov /* Called from eBPF program */ 194a10423b8SAlexei Starovoitov static void *percpu_array_map_lookup_elem(struct bpf_map *map, void *key) 195a10423b8SAlexei Starovoitov { 196a10423b8SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 197a10423b8SAlexei Starovoitov u32 index = *(u32 *)key; 198a10423b8SAlexei Starovoitov 199a10423b8SAlexei Starovoitov if (unlikely(index >= array->map.max_entries)) 200a10423b8SAlexei Starovoitov return NULL; 201a10423b8SAlexei Starovoitov 202b2157399SAlexei Starovoitov return this_cpu_ptr(array->pptrs[index & array->index_mask]); 203a10423b8SAlexei Starovoitov } 204a10423b8SAlexei Starovoitov 20515a07b33SAlexei Starovoitov int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value) 20615a07b33SAlexei Starovoitov { 20715a07b33SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 20815a07b33SAlexei Starovoitov u32 index = *(u32 *)key; 20915a07b33SAlexei Starovoitov void __percpu *pptr; 21015a07b33SAlexei Starovoitov int cpu, off = 0; 21115a07b33SAlexei Starovoitov u32 size; 21215a07b33SAlexei Starovoitov 21315a07b33SAlexei Starovoitov if (unlikely(index >= array->map.max_entries)) 21415a07b33SAlexei Starovoitov return -ENOENT; 21515a07b33SAlexei Starovoitov 21615a07b33SAlexei Starovoitov /* per_cpu areas are zero-filled and bpf programs can only 21715a07b33SAlexei Starovoitov * access 'value_size' of them, so copying rounded areas 21815a07b33SAlexei Starovoitov * will not leak any kernel data 21915a07b33SAlexei Starovoitov */ 22015a07b33SAlexei Starovoitov size = round_up(map->value_size, 8); 22115a07b33SAlexei Starovoitov rcu_read_lock(); 222b2157399SAlexei Starovoitov pptr = array->pptrs[index & array->index_mask]; 22315a07b33SAlexei Starovoitov for_each_possible_cpu(cpu) { 22415a07b33SAlexei Starovoitov bpf_long_memcpy(value + off, per_cpu_ptr(pptr, cpu), size); 22515a07b33SAlexei Starovoitov off += size; 22615a07b33SAlexei Starovoitov } 22715a07b33SAlexei Starovoitov rcu_read_unlock(); 22815a07b33SAlexei Starovoitov return 0; 22915a07b33SAlexei Starovoitov } 23015a07b33SAlexei Starovoitov 23128fbcfa0SAlexei Starovoitov /* Called from syscall */ 23228fbcfa0SAlexei Starovoitov static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key) 23328fbcfa0SAlexei Starovoitov { 23428fbcfa0SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 2358fe45924STeng Qin u32 index = key ? *(u32 *)key : U32_MAX; 23628fbcfa0SAlexei Starovoitov u32 *next = (u32 *)next_key; 23728fbcfa0SAlexei Starovoitov 23828fbcfa0SAlexei Starovoitov if (index >= array->map.max_entries) { 23928fbcfa0SAlexei Starovoitov *next = 0; 24028fbcfa0SAlexei Starovoitov return 0; 24128fbcfa0SAlexei Starovoitov } 24228fbcfa0SAlexei Starovoitov 24328fbcfa0SAlexei Starovoitov if (index == array->map.max_entries - 1) 24428fbcfa0SAlexei Starovoitov return -ENOENT; 24528fbcfa0SAlexei Starovoitov 24628fbcfa0SAlexei Starovoitov *next = index + 1; 24728fbcfa0SAlexei Starovoitov return 0; 24828fbcfa0SAlexei Starovoitov } 24928fbcfa0SAlexei Starovoitov 25028fbcfa0SAlexei Starovoitov /* Called from syscall or from eBPF program */ 25128fbcfa0SAlexei Starovoitov static int array_map_update_elem(struct bpf_map *map, void *key, void *value, 25228fbcfa0SAlexei Starovoitov u64 map_flags) 25328fbcfa0SAlexei Starovoitov { 25428fbcfa0SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 25528fbcfa0SAlexei Starovoitov u32 index = *(u32 *)key; 25628fbcfa0SAlexei Starovoitov 257a10423b8SAlexei Starovoitov if (unlikely(map_flags > BPF_EXIST)) 25828fbcfa0SAlexei Starovoitov /* unknown flags */ 25928fbcfa0SAlexei Starovoitov return -EINVAL; 26028fbcfa0SAlexei Starovoitov 261a10423b8SAlexei Starovoitov if (unlikely(index >= array->map.max_entries)) 26228fbcfa0SAlexei Starovoitov /* all elements were pre-allocated, cannot insert a new one */ 26328fbcfa0SAlexei Starovoitov return -E2BIG; 26428fbcfa0SAlexei Starovoitov 265a10423b8SAlexei Starovoitov if (unlikely(map_flags == BPF_NOEXIST)) 266daaf427cSAlexei Starovoitov /* all elements already exist */ 26728fbcfa0SAlexei Starovoitov return -EEXIST; 26828fbcfa0SAlexei Starovoitov 269a10423b8SAlexei Starovoitov if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) 270b2157399SAlexei Starovoitov memcpy(this_cpu_ptr(array->pptrs[index & array->index_mask]), 271a10423b8SAlexei Starovoitov value, map->value_size); 272a10423b8SAlexei Starovoitov else 273b2157399SAlexei Starovoitov memcpy(array->value + 274b2157399SAlexei Starovoitov array->elem_size * (index & array->index_mask), 275a10423b8SAlexei Starovoitov value, map->value_size); 27628fbcfa0SAlexei Starovoitov return 0; 27728fbcfa0SAlexei Starovoitov } 27828fbcfa0SAlexei Starovoitov 27915a07b33SAlexei Starovoitov int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value, 28015a07b33SAlexei Starovoitov u64 map_flags) 28115a07b33SAlexei Starovoitov { 28215a07b33SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 28315a07b33SAlexei Starovoitov u32 index = *(u32 *)key; 28415a07b33SAlexei Starovoitov void __percpu *pptr; 28515a07b33SAlexei Starovoitov int cpu, off = 0; 28615a07b33SAlexei Starovoitov u32 size; 28715a07b33SAlexei Starovoitov 28815a07b33SAlexei Starovoitov if (unlikely(map_flags > BPF_EXIST)) 28915a07b33SAlexei Starovoitov /* unknown flags */ 29015a07b33SAlexei Starovoitov return -EINVAL; 29115a07b33SAlexei Starovoitov 29215a07b33SAlexei Starovoitov if (unlikely(index >= array->map.max_entries)) 29315a07b33SAlexei Starovoitov /* all elements were pre-allocated, cannot insert a new one */ 29415a07b33SAlexei Starovoitov return -E2BIG; 29515a07b33SAlexei Starovoitov 29615a07b33SAlexei Starovoitov if (unlikely(map_flags == BPF_NOEXIST)) 29715a07b33SAlexei Starovoitov /* all elements already exist */ 29815a07b33SAlexei Starovoitov return -EEXIST; 29915a07b33SAlexei Starovoitov 30015a07b33SAlexei Starovoitov /* the user space will provide round_up(value_size, 8) bytes that 30115a07b33SAlexei Starovoitov * will be copied into per-cpu area. bpf programs can only access 30215a07b33SAlexei Starovoitov * value_size of it. During lookup the same extra bytes will be 30315a07b33SAlexei Starovoitov * returned or zeros which were zero-filled by percpu_alloc, 30415a07b33SAlexei Starovoitov * so no kernel data leaks possible 30515a07b33SAlexei Starovoitov */ 30615a07b33SAlexei Starovoitov size = round_up(map->value_size, 8); 30715a07b33SAlexei Starovoitov rcu_read_lock(); 308b2157399SAlexei Starovoitov pptr = array->pptrs[index & array->index_mask]; 30915a07b33SAlexei Starovoitov for_each_possible_cpu(cpu) { 31015a07b33SAlexei Starovoitov bpf_long_memcpy(per_cpu_ptr(pptr, cpu), value + off, size); 31115a07b33SAlexei Starovoitov off += size; 31215a07b33SAlexei Starovoitov } 31315a07b33SAlexei Starovoitov rcu_read_unlock(); 31415a07b33SAlexei Starovoitov return 0; 31515a07b33SAlexei Starovoitov } 31615a07b33SAlexei Starovoitov 31728fbcfa0SAlexei Starovoitov /* Called from syscall or from eBPF program */ 31828fbcfa0SAlexei Starovoitov static int array_map_delete_elem(struct bpf_map *map, void *key) 31928fbcfa0SAlexei Starovoitov { 32028fbcfa0SAlexei Starovoitov return -EINVAL; 32128fbcfa0SAlexei Starovoitov } 32228fbcfa0SAlexei Starovoitov 32328fbcfa0SAlexei Starovoitov /* Called when map->refcnt goes to zero, either from workqueue or from syscall */ 32428fbcfa0SAlexei Starovoitov static void array_map_free(struct bpf_map *map) 32528fbcfa0SAlexei Starovoitov { 32628fbcfa0SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 32728fbcfa0SAlexei Starovoitov 32828fbcfa0SAlexei Starovoitov /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0, 32928fbcfa0SAlexei Starovoitov * so the programs (can be more than one that used this map) were 33028fbcfa0SAlexei Starovoitov * disconnected from events. Wait for outstanding programs to complete 33128fbcfa0SAlexei Starovoitov * and free the array 33228fbcfa0SAlexei Starovoitov */ 33328fbcfa0SAlexei Starovoitov synchronize_rcu(); 33428fbcfa0SAlexei Starovoitov 335a10423b8SAlexei Starovoitov if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) 336a10423b8SAlexei Starovoitov bpf_array_free_percpu(array); 337a10423b8SAlexei Starovoitov 338d407bd25SDaniel Borkmann bpf_map_area_free(array); 33928fbcfa0SAlexei Starovoitov } 34028fbcfa0SAlexei Starovoitov 341a26ca7c9SMartin KaFai Lau static void array_map_seq_show_elem(struct bpf_map *map, void *key, 342a26ca7c9SMartin KaFai Lau struct seq_file *m) 343a26ca7c9SMartin KaFai Lau { 344a26ca7c9SMartin KaFai Lau void *value; 345a26ca7c9SMartin KaFai Lau 346a26ca7c9SMartin KaFai Lau rcu_read_lock(); 347a26ca7c9SMartin KaFai Lau 348a26ca7c9SMartin KaFai Lau value = array_map_lookup_elem(map, key); 349a26ca7c9SMartin KaFai Lau if (!value) { 350a26ca7c9SMartin KaFai Lau rcu_read_unlock(); 351a26ca7c9SMartin KaFai Lau return; 352a26ca7c9SMartin KaFai Lau } 353a26ca7c9SMartin KaFai Lau 354a26ca7c9SMartin KaFai Lau seq_printf(m, "%u: ", *(u32 *)key); 3559b2cf328SMartin KaFai Lau btf_type_seq_show(map->btf, map->btf_value_type_id, value, m); 356a26ca7c9SMartin KaFai Lau seq_puts(m, "\n"); 357a26ca7c9SMartin KaFai Lau 358a26ca7c9SMartin KaFai Lau rcu_read_unlock(); 359a26ca7c9SMartin KaFai Lau } 360a26ca7c9SMartin KaFai Lau 361*e8d2bec0SDaniel Borkmann static int array_map_check_btf(const struct bpf_map *map, 362*e8d2bec0SDaniel Borkmann const struct btf_type *key_type, 363*e8d2bec0SDaniel Borkmann const struct btf_type *value_type) 364a26ca7c9SMartin KaFai Lau { 365a26ca7c9SMartin KaFai Lau u32 int_data; 366a26ca7c9SMartin KaFai Lau 367*e8d2bec0SDaniel Borkmann if (BTF_INFO_KIND(key_type->info) != BTF_KIND_INT) 368a26ca7c9SMartin KaFai Lau return -EINVAL; 369a26ca7c9SMartin KaFai Lau 370a26ca7c9SMartin KaFai Lau int_data = *(u32 *)(key_type + 1); 371*e8d2bec0SDaniel Borkmann /* bpf array can only take a u32 key. This check makes sure 372*e8d2bec0SDaniel Borkmann * that the btf matches the attr used during map_create. 373a26ca7c9SMartin KaFai Lau */ 374*e8d2bec0SDaniel Borkmann if (BTF_INT_BITS(int_data) != 32 || BTF_INT_OFFSET(int_data)) 375a26ca7c9SMartin KaFai Lau return -EINVAL; 376a26ca7c9SMartin KaFai Lau 377a26ca7c9SMartin KaFai Lau return 0; 378a26ca7c9SMartin KaFai Lau } 379a26ca7c9SMartin KaFai Lau 38040077e0cSJohannes Berg const struct bpf_map_ops array_map_ops = { 381ad46061fSJakub Kicinski .map_alloc_check = array_map_alloc_check, 38228fbcfa0SAlexei Starovoitov .map_alloc = array_map_alloc, 38328fbcfa0SAlexei Starovoitov .map_free = array_map_free, 38428fbcfa0SAlexei Starovoitov .map_get_next_key = array_map_get_next_key, 38528fbcfa0SAlexei Starovoitov .map_lookup_elem = array_map_lookup_elem, 38628fbcfa0SAlexei Starovoitov .map_update_elem = array_map_update_elem, 38728fbcfa0SAlexei Starovoitov .map_delete_elem = array_map_delete_elem, 38881ed18abSAlexei Starovoitov .map_gen_lookup = array_map_gen_lookup, 389a26ca7c9SMartin KaFai Lau .map_seq_show_elem = array_map_seq_show_elem, 390a26ca7c9SMartin KaFai Lau .map_check_btf = array_map_check_btf, 39128fbcfa0SAlexei Starovoitov }; 39228fbcfa0SAlexei Starovoitov 39340077e0cSJohannes Berg const struct bpf_map_ops percpu_array_map_ops = { 394ad46061fSJakub Kicinski .map_alloc_check = array_map_alloc_check, 395a10423b8SAlexei Starovoitov .map_alloc = array_map_alloc, 396a10423b8SAlexei Starovoitov .map_free = array_map_free, 397a10423b8SAlexei Starovoitov .map_get_next_key = array_map_get_next_key, 398a10423b8SAlexei Starovoitov .map_lookup_elem = percpu_array_map_lookup_elem, 399a10423b8SAlexei Starovoitov .map_update_elem = array_map_update_elem, 400a10423b8SAlexei Starovoitov .map_delete_elem = array_map_delete_elem, 401*e8d2bec0SDaniel Borkmann .map_check_btf = array_map_check_btf, 402a10423b8SAlexei Starovoitov }; 403a10423b8SAlexei Starovoitov 404ad46061fSJakub Kicinski static int fd_array_map_alloc_check(union bpf_attr *attr) 40504fd61abSAlexei Starovoitov { 4062a36f0b9SWang Nan /* only file descriptors can be stored in this type of map */ 40704fd61abSAlexei Starovoitov if (attr->value_size != sizeof(u32)) 408ad46061fSJakub Kicinski return -EINVAL; 409ad46061fSJakub Kicinski return array_map_alloc_check(attr); 41004fd61abSAlexei Starovoitov } 41104fd61abSAlexei Starovoitov 4122a36f0b9SWang Nan static void fd_array_map_free(struct bpf_map *map) 41304fd61abSAlexei Starovoitov { 41404fd61abSAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 41504fd61abSAlexei Starovoitov int i; 41604fd61abSAlexei Starovoitov 41704fd61abSAlexei Starovoitov synchronize_rcu(); 41804fd61abSAlexei Starovoitov 41904fd61abSAlexei Starovoitov /* make sure it's empty */ 42004fd61abSAlexei Starovoitov for (i = 0; i < array->map.max_entries; i++) 4212a36f0b9SWang Nan BUG_ON(array->ptrs[i] != NULL); 422d407bd25SDaniel Borkmann 423d407bd25SDaniel Borkmann bpf_map_area_free(array); 42404fd61abSAlexei Starovoitov } 42504fd61abSAlexei Starovoitov 4262a36f0b9SWang Nan static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key) 42704fd61abSAlexei Starovoitov { 42804fd61abSAlexei Starovoitov return NULL; 42904fd61abSAlexei Starovoitov } 43004fd61abSAlexei Starovoitov 43104fd61abSAlexei Starovoitov /* only called from syscall */ 43214dc6f04SMartin KaFai Lau int bpf_fd_array_map_lookup_elem(struct bpf_map *map, void *key, u32 *value) 43314dc6f04SMartin KaFai Lau { 43414dc6f04SMartin KaFai Lau void **elem, *ptr; 43514dc6f04SMartin KaFai Lau int ret = 0; 43614dc6f04SMartin KaFai Lau 43714dc6f04SMartin KaFai Lau if (!map->ops->map_fd_sys_lookup_elem) 43814dc6f04SMartin KaFai Lau return -ENOTSUPP; 43914dc6f04SMartin KaFai Lau 44014dc6f04SMartin KaFai Lau rcu_read_lock(); 44114dc6f04SMartin KaFai Lau elem = array_map_lookup_elem(map, key); 44214dc6f04SMartin KaFai Lau if (elem && (ptr = READ_ONCE(*elem))) 44314dc6f04SMartin KaFai Lau *value = map->ops->map_fd_sys_lookup_elem(ptr); 44414dc6f04SMartin KaFai Lau else 44514dc6f04SMartin KaFai Lau ret = -ENOENT; 44614dc6f04SMartin KaFai Lau rcu_read_unlock(); 44714dc6f04SMartin KaFai Lau 44814dc6f04SMartin KaFai Lau return ret; 44914dc6f04SMartin KaFai Lau } 45014dc6f04SMartin KaFai Lau 45114dc6f04SMartin KaFai Lau /* only called from syscall */ 452d056a788SDaniel Borkmann int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file, 453d056a788SDaniel Borkmann void *key, void *value, u64 map_flags) 45404fd61abSAlexei Starovoitov { 45504fd61abSAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 4562a36f0b9SWang Nan void *new_ptr, *old_ptr; 45704fd61abSAlexei Starovoitov u32 index = *(u32 *)key, ufd; 45804fd61abSAlexei Starovoitov 45904fd61abSAlexei Starovoitov if (map_flags != BPF_ANY) 46004fd61abSAlexei Starovoitov return -EINVAL; 46104fd61abSAlexei Starovoitov 46204fd61abSAlexei Starovoitov if (index >= array->map.max_entries) 46304fd61abSAlexei Starovoitov return -E2BIG; 46404fd61abSAlexei Starovoitov 46504fd61abSAlexei Starovoitov ufd = *(u32 *)value; 466d056a788SDaniel Borkmann new_ptr = map->ops->map_fd_get_ptr(map, map_file, ufd); 4672a36f0b9SWang Nan if (IS_ERR(new_ptr)) 4682a36f0b9SWang Nan return PTR_ERR(new_ptr); 46904fd61abSAlexei Starovoitov 4702a36f0b9SWang Nan old_ptr = xchg(array->ptrs + index, new_ptr); 4712a36f0b9SWang Nan if (old_ptr) 4722a36f0b9SWang Nan map->ops->map_fd_put_ptr(old_ptr); 47304fd61abSAlexei Starovoitov 47404fd61abSAlexei Starovoitov return 0; 47504fd61abSAlexei Starovoitov } 47604fd61abSAlexei Starovoitov 4772a36f0b9SWang Nan static int fd_array_map_delete_elem(struct bpf_map *map, void *key) 47804fd61abSAlexei Starovoitov { 47904fd61abSAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 4802a36f0b9SWang Nan void *old_ptr; 48104fd61abSAlexei Starovoitov u32 index = *(u32 *)key; 48204fd61abSAlexei Starovoitov 48304fd61abSAlexei Starovoitov if (index >= array->map.max_entries) 48404fd61abSAlexei Starovoitov return -E2BIG; 48504fd61abSAlexei Starovoitov 4862a36f0b9SWang Nan old_ptr = xchg(array->ptrs + index, NULL); 4872a36f0b9SWang Nan if (old_ptr) { 4882a36f0b9SWang Nan map->ops->map_fd_put_ptr(old_ptr); 48904fd61abSAlexei Starovoitov return 0; 49004fd61abSAlexei Starovoitov } else { 49104fd61abSAlexei Starovoitov return -ENOENT; 49204fd61abSAlexei Starovoitov } 49304fd61abSAlexei Starovoitov } 49404fd61abSAlexei Starovoitov 495d056a788SDaniel Borkmann static void *prog_fd_array_get_ptr(struct bpf_map *map, 496d056a788SDaniel Borkmann struct file *map_file, int fd) 4972a36f0b9SWang Nan { 4982a36f0b9SWang Nan struct bpf_array *array = container_of(map, struct bpf_array, map); 4992a36f0b9SWang Nan struct bpf_prog *prog = bpf_prog_get(fd); 500d056a788SDaniel Borkmann 5012a36f0b9SWang Nan if (IS_ERR(prog)) 5022a36f0b9SWang Nan return prog; 5032a36f0b9SWang Nan 5042a36f0b9SWang Nan if (!bpf_prog_array_compatible(array, prog)) { 5052a36f0b9SWang Nan bpf_prog_put(prog); 5062a36f0b9SWang Nan return ERR_PTR(-EINVAL); 5072a36f0b9SWang Nan } 508d056a788SDaniel Borkmann 5092a36f0b9SWang Nan return prog; 5102a36f0b9SWang Nan } 5112a36f0b9SWang Nan 5122a36f0b9SWang Nan static void prog_fd_array_put_ptr(void *ptr) 5132a36f0b9SWang Nan { 5141aacde3dSDaniel Borkmann bpf_prog_put(ptr); 5152a36f0b9SWang Nan } 5162a36f0b9SWang Nan 51714dc6f04SMartin KaFai Lau static u32 prog_fd_array_sys_lookup_elem(void *ptr) 51814dc6f04SMartin KaFai Lau { 51914dc6f04SMartin KaFai Lau return ((struct bpf_prog *)ptr)->aux->id; 52014dc6f04SMartin KaFai Lau } 52114dc6f04SMartin KaFai Lau 52204fd61abSAlexei Starovoitov /* decrement refcnt of all bpf_progs that are stored in this map */ 523ba6b8de4SJohn Fastabend static void bpf_fd_array_map_clear(struct bpf_map *map) 52404fd61abSAlexei Starovoitov { 52504fd61abSAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 52604fd61abSAlexei Starovoitov int i; 52704fd61abSAlexei Starovoitov 52804fd61abSAlexei Starovoitov for (i = 0; i < array->map.max_entries; i++) 5292a36f0b9SWang Nan fd_array_map_delete_elem(map, &i); 53004fd61abSAlexei Starovoitov } 53104fd61abSAlexei Starovoitov 53240077e0cSJohannes Berg const struct bpf_map_ops prog_array_map_ops = { 533ad46061fSJakub Kicinski .map_alloc_check = fd_array_map_alloc_check, 534ad46061fSJakub Kicinski .map_alloc = array_map_alloc, 5352a36f0b9SWang Nan .map_free = fd_array_map_free, 53604fd61abSAlexei Starovoitov .map_get_next_key = array_map_get_next_key, 5372a36f0b9SWang Nan .map_lookup_elem = fd_array_map_lookup_elem, 5382a36f0b9SWang Nan .map_delete_elem = fd_array_map_delete_elem, 5392a36f0b9SWang Nan .map_fd_get_ptr = prog_fd_array_get_ptr, 5402a36f0b9SWang Nan .map_fd_put_ptr = prog_fd_array_put_ptr, 54114dc6f04SMartin KaFai Lau .map_fd_sys_lookup_elem = prog_fd_array_sys_lookup_elem, 542ba6b8de4SJohn Fastabend .map_release_uref = bpf_fd_array_map_clear, 543*e8d2bec0SDaniel Borkmann .map_check_btf = map_check_no_btf, 54404fd61abSAlexei Starovoitov }; 54504fd61abSAlexei Starovoitov 5463b1efb19SDaniel Borkmann static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file, 5473b1efb19SDaniel Borkmann struct file *map_file) 548ea317b26SKaixu Xia { 5493b1efb19SDaniel Borkmann struct bpf_event_entry *ee; 5503b1efb19SDaniel Borkmann 551858d68f1SDaniel Borkmann ee = kzalloc(sizeof(*ee), GFP_ATOMIC); 5523b1efb19SDaniel Borkmann if (ee) { 5533b1efb19SDaniel Borkmann ee->event = perf_file->private_data; 5543b1efb19SDaniel Borkmann ee->perf_file = perf_file; 5553b1efb19SDaniel Borkmann ee->map_file = map_file; 5563b1efb19SDaniel Borkmann } 5573b1efb19SDaniel Borkmann 5583b1efb19SDaniel Borkmann return ee; 5593b1efb19SDaniel Borkmann } 5603b1efb19SDaniel Borkmann 5613b1efb19SDaniel Borkmann static void __bpf_event_entry_free(struct rcu_head *rcu) 5623b1efb19SDaniel Borkmann { 5633b1efb19SDaniel Borkmann struct bpf_event_entry *ee; 5643b1efb19SDaniel Borkmann 5653b1efb19SDaniel Borkmann ee = container_of(rcu, struct bpf_event_entry, rcu); 5663b1efb19SDaniel Borkmann fput(ee->perf_file); 5673b1efb19SDaniel Borkmann kfree(ee); 5683b1efb19SDaniel Borkmann } 5693b1efb19SDaniel Borkmann 5703b1efb19SDaniel Borkmann static void bpf_event_entry_free_rcu(struct bpf_event_entry *ee) 5713b1efb19SDaniel Borkmann { 5723b1efb19SDaniel Borkmann call_rcu(&ee->rcu, __bpf_event_entry_free); 573ea317b26SKaixu Xia } 574ea317b26SKaixu Xia 575d056a788SDaniel Borkmann static void *perf_event_fd_array_get_ptr(struct bpf_map *map, 576d056a788SDaniel Borkmann struct file *map_file, int fd) 577ea317b26SKaixu Xia { 5783b1efb19SDaniel Borkmann struct bpf_event_entry *ee; 5793b1efb19SDaniel Borkmann struct perf_event *event; 5803b1efb19SDaniel Borkmann struct file *perf_file; 581f91840a3SAlexei Starovoitov u64 value; 582ea317b26SKaixu Xia 5833b1efb19SDaniel Borkmann perf_file = perf_event_get(fd); 5843b1efb19SDaniel Borkmann if (IS_ERR(perf_file)) 5853b1efb19SDaniel Borkmann return perf_file; 586e03e7ee3SAlexei Starovoitov 587f91840a3SAlexei Starovoitov ee = ERR_PTR(-EOPNOTSUPP); 5883b1efb19SDaniel Borkmann event = perf_file->private_data; 58997562633SYonghong Song if (perf_event_read_local(event, &value, NULL, NULL) == -EOPNOTSUPP) 5903b1efb19SDaniel Borkmann goto err_out; 591ea317b26SKaixu Xia 5923b1efb19SDaniel Borkmann ee = bpf_event_entry_gen(perf_file, map_file); 5933b1efb19SDaniel Borkmann if (ee) 5943b1efb19SDaniel Borkmann return ee; 5953b1efb19SDaniel Borkmann ee = ERR_PTR(-ENOMEM); 5963b1efb19SDaniel Borkmann err_out: 5973b1efb19SDaniel Borkmann fput(perf_file); 5983b1efb19SDaniel Borkmann return ee; 599ea317b26SKaixu Xia } 600ea317b26SKaixu Xia 601ea317b26SKaixu Xia static void perf_event_fd_array_put_ptr(void *ptr) 602ea317b26SKaixu Xia { 6033b1efb19SDaniel Borkmann bpf_event_entry_free_rcu(ptr); 6043b1efb19SDaniel Borkmann } 6053b1efb19SDaniel Borkmann 6063b1efb19SDaniel Borkmann static void perf_event_fd_array_release(struct bpf_map *map, 6073b1efb19SDaniel Borkmann struct file *map_file) 6083b1efb19SDaniel Borkmann { 6093b1efb19SDaniel Borkmann struct bpf_array *array = container_of(map, struct bpf_array, map); 6103b1efb19SDaniel Borkmann struct bpf_event_entry *ee; 6113b1efb19SDaniel Borkmann int i; 6123b1efb19SDaniel Borkmann 6133b1efb19SDaniel Borkmann rcu_read_lock(); 6143b1efb19SDaniel Borkmann for (i = 0; i < array->map.max_entries; i++) { 6153b1efb19SDaniel Borkmann ee = READ_ONCE(array->ptrs[i]); 6163b1efb19SDaniel Borkmann if (ee && ee->map_file == map_file) 6173b1efb19SDaniel Borkmann fd_array_map_delete_elem(map, &i); 6183b1efb19SDaniel Borkmann } 6193b1efb19SDaniel Borkmann rcu_read_unlock(); 620ea317b26SKaixu Xia } 621ea317b26SKaixu Xia 62240077e0cSJohannes Berg const struct bpf_map_ops perf_event_array_map_ops = { 623ad46061fSJakub Kicinski .map_alloc_check = fd_array_map_alloc_check, 624ad46061fSJakub Kicinski .map_alloc = array_map_alloc, 6253b1efb19SDaniel Borkmann .map_free = fd_array_map_free, 626ea317b26SKaixu Xia .map_get_next_key = array_map_get_next_key, 627ea317b26SKaixu Xia .map_lookup_elem = fd_array_map_lookup_elem, 628ea317b26SKaixu Xia .map_delete_elem = fd_array_map_delete_elem, 629ea317b26SKaixu Xia .map_fd_get_ptr = perf_event_fd_array_get_ptr, 630ea317b26SKaixu Xia .map_fd_put_ptr = perf_event_fd_array_put_ptr, 6313b1efb19SDaniel Borkmann .map_release = perf_event_fd_array_release, 632*e8d2bec0SDaniel Borkmann .map_check_btf = map_check_no_btf, 633ea317b26SKaixu Xia }; 634ea317b26SKaixu Xia 63560d20f91SSargun Dhillon #ifdef CONFIG_CGROUPS 6364ed8ec52SMartin KaFai Lau static void *cgroup_fd_array_get_ptr(struct bpf_map *map, 6374ed8ec52SMartin KaFai Lau struct file *map_file /* not used */, 6384ed8ec52SMartin KaFai Lau int fd) 6394ed8ec52SMartin KaFai Lau { 6404ed8ec52SMartin KaFai Lau return cgroup_get_from_fd(fd); 6414ed8ec52SMartin KaFai Lau } 6424ed8ec52SMartin KaFai Lau 6434ed8ec52SMartin KaFai Lau static void cgroup_fd_array_put_ptr(void *ptr) 6444ed8ec52SMartin KaFai Lau { 6454ed8ec52SMartin KaFai Lau /* cgroup_put free cgrp after a rcu grace period */ 6464ed8ec52SMartin KaFai Lau cgroup_put(ptr); 6474ed8ec52SMartin KaFai Lau } 6484ed8ec52SMartin KaFai Lau 6494ed8ec52SMartin KaFai Lau static void cgroup_fd_array_free(struct bpf_map *map) 6504ed8ec52SMartin KaFai Lau { 6514ed8ec52SMartin KaFai Lau bpf_fd_array_map_clear(map); 6524ed8ec52SMartin KaFai Lau fd_array_map_free(map); 6534ed8ec52SMartin KaFai Lau } 6544ed8ec52SMartin KaFai Lau 65540077e0cSJohannes Berg const struct bpf_map_ops cgroup_array_map_ops = { 656ad46061fSJakub Kicinski .map_alloc_check = fd_array_map_alloc_check, 657ad46061fSJakub Kicinski .map_alloc = array_map_alloc, 6584ed8ec52SMartin KaFai Lau .map_free = cgroup_fd_array_free, 6594ed8ec52SMartin KaFai Lau .map_get_next_key = array_map_get_next_key, 6604ed8ec52SMartin KaFai Lau .map_lookup_elem = fd_array_map_lookup_elem, 6614ed8ec52SMartin KaFai Lau .map_delete_elem = fd_array_map_delete_elem, 6624ed8ec52SMartin KaFai Lau .map_fd_get_ptr = cgroup_fd_array_get_ptr, 6634ed8ec52SMartin KaFai Lau .map_fd_put_ptr = cgroup_fd_array_put_ptr, 664*e8d2bec0SDaniel Borkmann .map_check_btf = map_check_no_btf, 6654ed8ec52SMartin KaFai Lau }; 6664ed8ec52SMartin KaFai Lau #endif 66756f668dfSMartin KaFai Lau 66856f668dfSMartin KaFai Lau static struct bpf_map *array_of_map_alloc(union bpf_attr *attr) 66956f668dfSMartin KaFai Lau { 67056f668dfSMartin KaFai Lau struct bpf_map *map, *inner_map_meta; 67156f668dfSMartin KaFai Lau 67256f668dfSMartin KaFai Lau inner_map_meta = bpf_map_meta_alloc(attr->inner_map_fd); 67356f668dfSMartin KaFai Lau if (IS_ERR(inner_map_meta)) 67456f668dfSMartin KaFai Lau return inner_map_meta; 67556f668dfSMartin KaFai Lau 676ad46061fSJakub Kicinski map = array_map_alloc(attr); 67756f668dfSMartin KaFai Lau if (IS_ERR(map)) { 67856f668dfSMartin KaFai Lau bpf_map_meta_free(inner_map_meta); 67956f668dfSMartin KaFai Lau return map; 68056f668dfSMartin KaFai Lau } 68156f668dfSMartin KaFai Lau 68256f668dfSMartin KaFai Lau map->inner_map_meta = inner_map_meta; 68356f668dfSMartin KaFai Lau 68456f668dfSMartin KaFai Lau return map; 68556f668dfSMartin KaFai Lau } 68656f668dfSMartin KaFai Lau 68756f668dfSMartin KaFai Lau static void array_of_map_free(struct bpf_map *map) 68856f668dfSMartin KaFai Lau { 68956f668dfSMartin KaFai Lau /* map->inner_map_meta is only accessed by syscall which 69056f668dfSMartin KaFai Lau * is protected by fdget/fdput. 69156f668dfSMartin KaFai Lau */ 69256f668dfSMartin KaFai Lau bpf_map_meta_free(map->inner_map_meta); 69356f668dfSMartin KaFai Lau bpf_fd_array_map_clear(map); 69456f668dfSMartin KaFai Lau fd_array_map_free(map); 69556f668dfSMartin KaFai Lau } 69656f668dfSMartin KaFai Lau 69756f668dfSMartin KaFai Lau static void *array_of_map_lookup_elem(struct bpf_map *map, void *key) 69856f668dfSMartin KaFai Lau { 69956f668dfSMartin KaFai Lau struct bpf_map **inner_map = array_map_lookup_elem(map, key); 70056f668dfSMartin KaFai Lau 70156f668dfSMartin KaFai Lau if (!inner_map) 70256f668dfSMartin KaFai Lau return NULL; 70356f668dfSMartin KaFai Lau 70456f668dfSMartin KaFai Lau return READ_ONCE(*inner_map); 70556f668dfSMartin KaFai Lau } 70656f668dfSMartin KaFai Lau 7077b0c2a05SDaniel Borkmann static u32 array_of_map_gen_lookup(struct bpf_map *map, 7087b0c2a05SDaniel Borkmann struct bpf_insn *insn_buf) 7097b0c2a05SDaniel Borkmann { 710b2157399SAlexei Starovoitov struct bpf_array *array = container_of(map, struct bpf_array, map); 7117b0c2a05SDaniel Borkmann u32 elem_size = round_up(map->value_size, 8); 7127b0c2a05SDaniel Borkmann struct bpf_insn *insn = insn_buf; 7137b0c2a05SDaniel Borkmann const int ret = BPF_REG_0; 7147b0c2a05SDaniel Borkmann const int map_ptr = BPF_REG_1; 7157b0c2a05SDaniel Borkmann const int index = BPF_REG_2; 7167b0c2a05SDaniel Borkmann 7177b0c2a05SDaniel Borkmann *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value)); 7187b0c2a05SDaniel Borkmann *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0); 719b2157399SAlexei Starovoitov if (map->unpriv_array) { 720b2157399SAlexei Starovoitov *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 6); 721b2157399SAlexei Starovoitov *insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask); 722b2157399SAlexei Starovoitov } else { 7237b0c2a05SDaniel Borkmann *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 5); 724b2157399SAlexei Starovoitov } 7257b0c2a05SDaniel Borkmann if (is_power_of_2(elem_size)) 7267b0c2a05SDaniel Borkmann *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size)); 7277b0c2a05SDaniel Borkmann else 7287b0c2a05SDaniel Borkmann *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size); 7297b0c2a05SDaniel Borkmann *insn++ = BPF_ALU64_REG(BPF_ADD, ret, map_ptr); 7307b0c2a05SDaniel Borkmann *insn++ = BPF_LDX_MEM(BPF_DW, ret, ret, 0); 7317b0c2a05SDaniel Borkmann *insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 1); 7327b0c2a05SDaniel Borkmann *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1); 7337b0c2a05SDaniel Borkmann *insn++ = BPF_MOV64_IMM(ret, 0); 7347b0c2a05SDaniel Borkmann 7357b0c2a05SDaniel Borkmann return insn - insn_buf; 7367b0c2a05SDaniel Borkmann } 7377b0c2a05SDaniel Borkmann 73840077e0cSJohannes Berg const struct bpf_map_ops array_of_maps_map_ops = { 739ad46061fSJakub Kicinski .map_alloc_check = fd_array_map_alloc_check, 74056f668dfSMartin KaFai Lau .map_alloc = array_of_map_alloc, 74156f668dfSMartin KaFai Lau .map_free = array_of_map_free, 74256f668dfSMartin KaFai Lau .map_get_next_key = array_map_get_next_key, 74356f668dfSMartin KaFai Lau .map_lookup_elem = array_of_map_lookup_elem, 74456f668dfSMartin KaFai Lau .map_delete_elem = fd_array_map_delete_elem, 74556f668dfSMartin KaFai Lau .map_fd_get_ptr = bpf_map_fd_get_ptr, 74656f668dfSMartin KaFai Lau .map_fd_put_ptr = bpf_map_fd_put_ptr, 74714dc6f04SMartin KaFai Lau .map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem, 7487b0c2a05SDaniel Borkmann .map_gen_lookup = array_of_map_gen_lookup, 749*e8d2bec0SDaniel Borkmann .map_check_btf = map_check_no_btf, 75056f668dfSMartin KaFai Lau }; 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