We have implemented memory usage callback for all maps, and we enforce any newly added map having a callback as well. We will check the callback at map creation time. If a map doesn't have the callback, it will return EINVAL. Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx> --- kernel/bpf/syscall.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index e12b03e..cbe7ff3 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -129,6 +129,8 @@ static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) } if (attr->map_ifindex) ops = &bpf_map_offload_ops; + if (!ops->map_mem_usage) + return ERR_PTR(-EINVAL); map = ops->map_alloc(attr); if (IS_ERR(map)) return map; @@ -775,13 +777,7 @@ static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f) /* Show the memory usage of a bpf map */ static u64 bpf_map_memory_usage(const struct bpf_map *map) { - unsigned long size; - - if (map->ops->map_mem_usage) - return map->ops->map_mem_usage(map); - - size = round_up(map->key_size + bpf_map_value_size(map), 8); - return round_up(map->max_entries * size, PAGE_SIZE); + return map->ops->map_mem_usage(map); } static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) -- 1.8.3.1