diff options
| author | Mykyta Yatsenko <yatsenko@meta.com> | 2025-09-23 12:24:01 +0100 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-09-23 07:34:38 -0700 |
| commit | 5e8134f50d3041a9922a732f24d705a238b61aad (patch) | |
| tree | f3870c9e9a239766c4d276ccd69c04b36a6c01c3 /kernel/bpf/helpers.c | |
| parent | 5c8fd7e2b5b0a527cf88740da122166695382a78 (diff) | |
bpf: extract map key pointer calculation
Calculation of the BPF map key, given the pointer to a value is
duplicated in a couple of places in helpers already, in the next patch
another use case is introduced as well.
This patch extracts that functionality into a separate function.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250923112404.668720-7-mykyta.yatsenko5@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf/helpers.c')
| -rw-r--r-- | kernel/bpf/helpers.c | 30 |
1 files changed, 13 insertions, 17 deletions
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 7f5e528df13b..c28f48a310e3 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -1082,6 +1082,17 @@ const struct bpf_func_proto bpf_snprintf_proto = { .arg5_type = ARG_CONST_SIZE_OR_ZERO, }; +static void *map_key_from_value(struct bpf_map *map, void *value, u32 *arr_idx) +{ + if (map->map_type == BPF_MAP_TYPE_ARRAY) { + struct bpf_array *array = container_of(map, struct bpf_array, map); + + *arr_idx = ((char *)value - array->value) / array->elem_size; + return arr_idx; + } + return (void *)value - round_up(map->key_size, 8); +} + struct bpf_async_cb { struct bpf_map *map; struct bpf_prog *prog; @@ -1164,15 +1175,8 @@ static enum hrtimer_restart bpf_timer_cb(struct hrtimer *hrtimer) * bpf_map_delete_elem() on the same timer. */ this_cpu_write(hrtimer_running, t); - if (map->map_type == BPF_MAP_TYPE_ARRAY) { - struct bpf_array *array = container_of(map, struct bpf_array, map); - /* compute the key */ - idx = ((char *)value - array->value) / array->elem_size; - key = &idx; - } else { /* hash or lru */ - key = value - round_up(map->key_size, 8); - } + key = map_key_from_value(map, value, &idx); callback_fn((u64)(long)map, (u64)(long)key, (u64)(long)value, 0, 0); /* The verifier checked that return value is zero. */ @@ -1198,15 +1202,7 @@ static void bpf_wq_work(struct work_struct *work) if (!callback_fn) return; - if (map->map_type == BPF_MAP_TYPE_ARRAY) { - struct bpf_array *array = container_of(map, struct bpf_array, map); - - /* compute the key */ - idx = ((char *)value - array->value) / array->elem_size; - key = &idx; - } else { /* hash or lru */ - key = value - round_up(map->key_size, 8); - } + key = map_key_from_value(map, value, &idx); rcu_read_lock_trace(); migrate_disable(); |