Commit 06dcdcd4 authored by Yonghong Song's avatar Yonghong Song Committed by Alexei Starovoitov
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bpf: Add arraymap support for bpf_for_each_map_elem() helper 



This patch added support for arraymap and percpu arraymap.

Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210226204928.3885192-1-yhs@fb.com
parent 314ee05e

kernel/bpf/arraymap.c

+40 −0
Original line number Diff line number Diff line
@@ -625,6 +625,42 @@ static const struct bpf_iter_seq_info iter_seq_info = { 
	.seq_priv_size		= sizeof(struct bpf_iter_seq_array_map_info),

};



static int bpf_for_each_array_elem(struct bpf_map *map, void *callback_fn,

				   void *callback_ctx, u64 flags)

{

	u32 i, key, num_elems = 0;

	struct bpf_array *array;

	bool is_percpu;

	u64 ret = 0;

	void *val;



	if (flags != 0)

		return -EINVAL;



	is_percpu = map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;

	array = container_of(map, struct bpf_array, map);

	if (is_percpu)

		migrate_disable();

	for (i = 0; i < map->max_entries; i++) {

		if (is_percpu)

			val = this_cpu_ptr(array->pptrs[i]);

		else

			val = array->value + array->elem_size * i;

		num_elems++;

		key = i;

		ret = BPF_CAST_CALL(callback_fn)((u64)(long)map,

					(u64)(long)&key, (u64)(long)val,

					(u64)(long)callback_ctx, 0);

		/* return value: 0 - continue, 1 - stop and return */

		if (ret)

			break;

	}



	if (is_percpu)

		migrate_enable();

	return num_elems;

}



static int array_map_btf_id;

const struct bpf_map_ops array_map_ops = {

	.map_meta_equal = array_map_meta_equal,
@@ -643,6 +679,8 @@ const struct bpf_map_ops array_map_ops = { 
	.map_check_btf = array_map_check_btf,

	.map_lookup_batch = generic_map_lookup_batch,

	.map_update_batch = generic_map_update_batch,

	.map_set_for_each_callback_args = map_set_for_each_callback_args,

	.map_for_each_callback = bpf_for_each_array_elem,

	.map_btf_name = "bpf_array",

	.map_btf_id = &array_map_btf_id,

	.iter_seq_info = &iter_seq_info,
@@ -660,6 +698,8 @@ const struct bpf_map_ops percpu_array_map_ops = { 
	.map_delete_elem = array_map_delete_elem,

	.map_seq_show_elem = percpu_array_map_seq_show_elem,

	.map_check_btf = array_map_check_btf,

	.map_set_for_each_callback_args = map_set_for_each_callback_args,

	.map_for_each_callback = bpf_for_each_array_elem,

	.map_btf_name = "bpf_array",

	.map_btf_id = &percpu_array_map_btf_id,

	.iter_seq_info = &iter_seq_info,