Commit 6df4ea1f authored by Kumar Kartikeya Dwivedi's avatar Kumar Kartikeya Dwivedi Committed by Alexei Starovoitov
Browse files

bpf: Support kptrs in percpu arraymap 



Enable support for kptrs in percpu BPF arraymap by wiring up the freeing
of these kptrs from percpu map elements.

Signed-off-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220904204145.3089-3-memxor@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 44832519

kernel/bpf/arraymap.c

+24 −9
Original line number Diff line number Diff line
@@ -279,7 +279,8 @@ int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value) 
	rcu_read_lock();

	pptr = array->pptrs[index & array->index_mask];

	for_each_possible_cpu(cpu) {

		bpf_long_memcpy(value + off, per_cpu_ptr(pptr, cpu), size);

		copy_map_value_long(map, value + off, per_cpu_ptr(pptr, cpu));

		check_and_init_map_value(map, value + off);

		off += size;

	}

	rcu_read_unlock();
@@ -338,8 +339,9 @@ static int array_map_update_elem(struct bpf_map *map, void *key, void *value, 
		return -EINVAL;



	if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {

		memcpy(this_cpu_ptr(array->pptrs[index & array->index_mask]),

		       value, map->value_size);

		val = this_cpu_ptr(array->pptrs[index & array->index_mask]);

		copy_map_value(map, val, value);

		check_and_free_fields(array, val);

	} else {

		val = array->value +

			(u64)array->elem_size * (index & array->index_mask);
@@ -383,7 +385,8 @@ int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value, 
	rcu_read_lock();

	pptr = array->pptrs[index & array->index_mask];

	for_each_possible_cpu(cpu) {

		bpf_long_memcpy(per_cpu_ptr(pptr, cpu), value + off, size);

		copy_map_value_long(map, per_cpu_ptr(pptr, cpu), value + off);

		check_and_free_fields(array, per_cpu_ptr(pptr, cpu));

		off += size;

	}

	rcu_read_unlock();
@@ -421,8 +424,20 @@ static void array_map_free(struct bpf_map *map) 
	int i;



	if (map_value_has_kptrs(map)) {

		if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {

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

				void __percpu *pptr = array->pptrs[i & array->index_mask];

				int cpu;



				for_each_possible_cpu(cpu) {

					bpf_map_free_kptrs(map, per_cpu_ptr(pptr, cpu));

					cond_resched();

				}

			}

		} else {

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

				bpf_map_free_kptrs(map, array_map_elem_ptr(array, i));

		}

		bpf_map_free_kptr_off_tab(map);

	}
@@ -608,9 +623,9 @@ static int __bpf_array_map_seq_show(struct seq_file *seq, void *v) 
			pptr = v;

			size = array->elem_size;

			for_each_possible_cpu(cpu) {

				bpf_long_memcpy(info->percpu_value_buf + off,

						per_cpu_ptr(pptr, cpu),

						size);

				copy_map_value_long(map, info->percpu_value_buf + off,

						    per_cpu_ptr(pptr, cpu));

				check_and_init_map_value(map, info->percpu_value_buf + off);

				off += size;

			}

			ctx.value = info->percpu_value_buf;

kernel/bpf/syscall.c

+2 −1
Original line number Diff line number Diff line
@@ -1049,7 +1049,8 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf, 
		}

		if (map->map_type != BPF_MAP_TYPE_HASH &&

		    map->map_type != BPF_MAP_TYPE_LRU_HASH &&

		    map->map_type != BPF_MAP_TYPE_ARRAY) {

		    map->map_type != BPF_MAP_TYPE_ARRAY &&

		    map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY) {

			ret = -EOPNOTSUPP;

			goto free_map_tab;

		}