diff options
Diffstat (limited to 'kernel/bpf/hashtab.c')
| -rw-r--r-- | kernel/bpf/hashtab.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 3b9d297a53be..bc6bc8bb871d 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -125,6 +125,11 @@ struct htab_elem { char key[] __aligned(8); }; +struct htab_btf_record { + struct btf_record *record; + u32 key_size; +}; + static inline bool htab_is_prealloc(const struct bpf_htab *htab) { return !(htab->map.map_flags & BPF_F_NO_PREALLOC); @@ -457,6 +462,83 @@ static int htab_map_alloc_check(union bpf_attr *attr) return 0; } +static void htab_mem_dtor(void *obj, void *ctx) +{ + struct htab_btf_record *hrec = ctx; + struct htab_elem *elem = obj; + void *map_value; + + if (IS_ERR_OR_NULL(hrec->record)) + return; + + map_value = htab_elem_value(elem, hrec->key_size); + bpf_obj_free_fields(hrec->record, map_value); +} + +static void htab_pcpu_mem_dtor(void *obj, void *ctx) +{ + void __percpu *pptr = *(void __percpu **)obj; + struct htab_btf_record *hrec = ctx; + int cpu; + + if (IS_ERR_OR_NULL(hrec->record)) + return; + + for_each_possible_cpu(cpu) + bpf_obj_free_fields(hrec->record, per_cpu_ptr(pptr, cpu)); +} + +static void htab_dtor_ctx_free(void *ctx) +{ + struct htab_btf_record *hrec = ctx; + + btf_record_free(hrec->record); + kfree(ctx); +} + +static int htab_set_dtor(struct bpf_htab *htab, void (*dtor)(void *, void *)) +{ + u32 key_size = htab->map.key_size; + struct bpf_mem_alloc *ma; + struct htab_btf_record *hrec; + int err; + + /* No need for dtors. */ + if (IS_ERR_OR_NULL(htab->map.record)) + return 0; + + hrec = kzalloc(sizeof(*hrec), GFP_KERNEL); + if (!hrec) + return -ENOMEM; + hrec->key_size = key_size; + hrec->record = btf_record_dup(htab->map.record); + if (IS_ERR(hrec->record)) { + err = PTR_ERR(hrec->record); + kfree(hrec); + return err; + } + ma = htab_is_percpu(htab) ? &htab->pcpu_ma : &htab->ma; + bpf_mem_alloc_set_dtor(ma, dtor, htab_dtor_ctx_free, hrec); + return 0; +} + +static int htab_map_check_btf(struct bpf_map *map, const struct btf *btf, + const struct btf_type *key_type, const struct btf_type *value_type) +{ + struct bpf_htab *htab = container_of(map, struct bpf_htab, map); + + if (htab_is_prealloc(htab)) + return 0; + /* + * We must set the dtor using this callback, as map's BTF record is not + * populated in htab_map_alloc(), so it will always appear as NULL. + */ + if (htab_is_percpu(htab)) + return htab_set_dtor(htab, htab_pcpu_mem_dtor); + else + return htab_set_dtor(htab, htab_mem_dtor); +} + static struct bpf_map *htab_map_alloc(union bpf_attr *attr) { bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH || @@ -2281,6 +2363,7 @@ const struct bpf_map_ops htab_map_ops = { .map_seq_show_elem = htab_map_seq_show_elem, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_hash_elem, + .map_check_btf = htab_map_check_btf, .map_mem_usage = htab_map_mem_usage, BATCH_OPS(htab), .map_btf_id = &htab_map_btf_ids[0], @@ -2303,6 +2386,7 @@ const struct bpf_map_ops htab_lru_map_ops = { .map_seq_show_elem = htab_map_seq_show_elem, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_hash_elem, + .map_check_btf = htab_map_check_btf, .map_mem_usage = htab_map_mem_usage, BATCH_OPS(htab_lru), .map_btf_id = &htab_map_btf_ids[0], @@ -2482,6 +2566,7 @@ const struct bpf_map_ops htab_percpu_map_ops = { .map_seq_show_elem = htab_percpu_map_seq_show_elem, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_hash_elem, + .map_check_btf = htab_map_check_btf, .map_mem_usage = htab_map_mem_usage, BATCH_OPS(htab_percpu), .map_btf_id = &htab_map_btf_ids[0], @@ -2502,6 +2587,7 @@ const struct bpf_map_ops htab_lru_percpu_map_ops = { .map_seq_show_elem = htab_percpu_map_seq_show_elem, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_hash_elem, + .map_check_btf = htab_map_check_btf, .map_mem_usage = htab_map_mem_usage, BATCH_OPS(htab_lru_percpu), .map_btf_id = &htab_map_btf_ids[0], |