diff options
Diffstat (limited to 'kernel/bpf/arraymap.c')
| -rw-r--r-- | kernel/bpf/arraymap.c | 122 |
1 files changed, 58 insertions, 64 deletions
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index bcf9955fac95..5e00b2333c26 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -17,6 +17,8 @@ #include <linux/filter.h> #include <linux/perf_event.h> +#include "map_in_map.h" + static void bpf_array_free_percpu(struct bpf_array *array) { int i; @@ -117,20 +119,17 @@ static void *array_map_lookup_elem(struct bpf_map *map, void *key) /* emit BPF instructions equivalent to C code of array_map_lookup_elem() */ static u32 array_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf) { - struct bpf_array *array = container_of(map, struct bpf_array, map); struct bpf_insn *insn = insn_buf; - u32 elem_size = array->elem_size; + u32 elem_size = round_up(map->value_size, 8); const int ret = BPF_REG_0; const int map_ptr = BPF_REG_1; const int index = BPF_REG_2; *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value)); *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0); - *insn++ = BPF_JMP_IMM(BPF_JGE, ret, array->map.max_entries, - elem_size == 1 ? 2 : 3); - if (elem_size == 1) { - /* nop */ - } else if (is_power_of_2(elem_size)) { + *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 3); + + if (is_power_of_2(elem_size)) { *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size)); } else { *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size); @@ -183,7 +182,7 @@ int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value) static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key) { struct bpf_array *array = container_of(map, struct bpf_array, map); - u32 index = *(u32 *)key; + u32 index = key ? *(u32 *)key : U32_MAX; u32 *next = (u32 *)next_key; if (index >= array->map.max_entries) { @@ -288,7 +287,7 @@ static void array_map_free(struct bpf_map *map) bpf_map_area_free(array); } -static const struct bpf_map_ops array_ops = { +const struct bpf_map_ops array_map_ops = { .map_alloc = array_map_alloc, .map_free = array_map_free, .map_get_next_key = array_map_get_next_key, @@ -298,12 +297,7 @@ static const struct bpf_map_ops array_ops = { .map_gen_lookup = array_map_gen_lookup, }; -static struct bpf_map_type_list array_type __ro_after_init = { - .ops = &array_ops, - .type = BPF_MAP_TYPE_ARRAY, -}; - -static const struct bpf_map_ops percpu_array_ops = { +const struct bpf_map_ops percpu_array_map_ops = { .map_alloc = array_map_alloc, .map_free = array_map_free, .map_get_next_key = array_map_get_next_key, @@ -312,19 +306,6 @@ static const struct bpf_map_ops percpu_array_ops = { .map_delete_elem = array_map_delete_elem, }; -static struct bpf_map_type_list percpu_array_type __ro_after_init = { - .ops = &percpu_array_ops, - .type = BPF_MAP_TYPE_PERCPU_ARRAY, -}; - -static int __init register_array_map(void) -{ - bpf_register_map_type(&array_type); - bpf_register_map_type(&percpu_array_type); - return 0; -} -late_initcall(register_array_map); - static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr) { /* only file descriptors can be stored in this type of map */ @@ -428,7 +409,7 @@ void bpf_fd_array_map_clear(struct bpf_map *map) fd_array_map_delete_elem(map, &i); } -static const struct bpf_map_ops prog_array_ops = { +const struct bpf_map_ops prog_array_map_ops = { .map_alloc = fd_array_map_alloc, .map_free = fd_array_map_free, .map_get_next_key = array_map_get_next_key, @@ -438,18 +419,6 @@ static const struct bpf_map_ops prog_array_ops = { .map_fd_put_ptr = prog_fd_array_put_ptr, }; -static struct bpf_map_type_list prog_array_type __ro_after_init = { - .ops = &prog_array_ops, - .type = BPF_MAP_TYPE_PROG_ARRAY, -}; - -static int __init register_prog_array_map(void) -{ - bpf_register_map_type(&prog_array_type); - return 0; -} -late_initcall(register_prog_array_map); - static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file, struct file *map_file) { @@ -540,7 +509,7 @@ static void perf_event_fd_array_release(struct bpf_map *map, rcu_read_unlock(); } -static const struct bpf_map_ops perf_event_array_ops = { +const struct bpf_map_ops perf_event_array_map_ops = { .map_alloc = fd_array_map_alloc, .map_free = fd_array_map_free, .map_get_next_key = array_map_get_next_key, @@ -551,18 +520,6 @@ static const struct bpf_map_ops perf_event_array_ops = { .map_release = perf_event_fd_array_release, }; -static struct bpf_map_type_list perf_event_array_type __ro_after_init = { - .ops = &perf_event_array_ops, - .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY, -}; - -static int __init register_perf_event_array_map(void) -{ - bpf_register_map_type(&perf_event_array_type); - return 0; -} -late_initcall(register_perf_event_array_map); - #ifdef CONFIG_CGROUPS static void *cgroup_fd_array_get_ptr(struct bpf_map *map, struct file *map_file /* not used */, @@ -583,7 +540,7 @@ static void cgroup_fd_array_free(struct bpf_map *map) fd_array_map_free(map); } -static const struct bpf_map_ops cgroup_array_ops = { +const struct bpf_map_ops cgroup_array_map_ops = { .map_alloc = fd_array_map_alloc, .map_free = cgroup_fd_array_free, .map_get_next_key = array_map_get_next_key, @@ -592,16 +549,53 @@ static const struct bpf_map_ops cgroup_array_ops = { .map_fd_get_ptr = cgroup_fd_array_get_ptr, .map_fd_put_ptr = cgroup_fd_array_put_ptr, }; +#endif -static struct bpf_map_type_list cgroup_array_type __ro_after_init = { - .ops = &cgroup_array_ops, - .type = BPF_MAP_TYPE_CGROUP_ARRAY, -}; +static struct bpf_map *array_of_map_alloc(union bpf_attr *attr) +{ + struct bpf_map *map, *inner_map_meta; + + inner_map_meta = bpf_map_meta_alloc(attr->inner_map_fd); + if (IS_ERR(inner_map_meta)) + return inner_map_meta; + + map = fd_array_map_alloc(attr); + if (IS_ERR(map)) { + bpf_map_meta_free(inner_map_meta); + return map; + } -static int __init register_cgroup_array_map(void) + map->inner_map_meta = inner_map_meta; + + return map; +} + +static void array_of_map_free(struct bpf_map *map) { - bpf_register_map_type(&cgroup_array_type); - return 0; + /* map->inner_map_meta is only accessed by syscall which + * is protected by fdget/fdput. + */ + bpf_map_meta_free(map->inner_map_meta); + bpf_fd_array_map_clear(map); + fd_array_map_free(map); } -late_initcall(register_cgroup_array_map); -#endif + +static void *array_of_map_lookup_elem(struct bpf_map *map, void *key) +{ + struct bpf_map **inner_map = array_map_lookup_elem(map, key); + + if (!inner_map) + return NULL; + + return READ_ONCE(*inner_map); +} + +const struct bpf_map_ops array_of_maps_map_ops = { + .map_alloc = array_of_map_alloc, + .map_free = array_of_map_free, + .map_get_next_key = array_map_get_next_key, + .map_lookup_elem = array_of_map_lookup_elem, + .map_delete_elem = fd_array_map_delete_elem, + .map_fd_get_ptr = bpf_map_fd_get_ptr, + .map_fd_put_ptr = bpf_map_fd_put_ptr, +}; |