From b76f22269028fb252727a696084c70494d80a52c Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Fri, 21 Aug 2020 11:44:19 -0700 Subject: [PATCH] bpf: Implement link_query callbacks in map element iterators For bpf_map_elem and bpf_sk_local_storage bpf iterators, additional map_id should be shown for fdinfo and userspace query. For example, the following is for a bpf_map_elem iterator. $ cat /proc/1753/fdinfo/9 pos: 0 flags: 02000000 mnt_id: 14 link_type: iter link_id: 34 prog_tag: 104be6d3fe45e6aa prog_id: 173 target_name: bpf_map_elem map_id: 127 Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200821184419.574240-1-yhs@fb.com --- include/linux/bpf.h | 4 ++++ kernel/bpf/map_iter.c | 15 +++++++++++++++ net/core/bpf_sk_storage.c | 2 ++ 3 files changed, 21 insertions(+) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 529e9b183eeb..30c144af894a 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1256,6 +1256,10 @@ int bpf_iter_new_fd(struct bpf_link *link); bool bpf_link_is_iter(struct bpf_link *link); struct bpf_prog *bpf_iter_get_info(struct bpf_iter_meta *meta, bool in_stop); int bpf_iter_run_prog(struct bpf_prog *prog, void *ctx); +void bpf_iter_map_show_fdinfo(const struct bpf_iter_aux_info *aux, + struct seq_file *seq); +int bpf_iter_map_fill_link_info(const struct bpf_iter_aux_info *aux, + struct bpf_link_info *info); int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value); int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value); diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c index af86048e5afd..6a9542af4212 100644 --- a/kernel/bpf/map_iter.c +++ b/kernel/bpf/map_iter.c @@ -149,6 +149,19 @@ static void bpf_iter_detach_map(struct bpf_iter_aux_info *aux) bpf_map_put_with_uref(aux->map); } +void bpf_iter_map_show_fdinfo(const struct bpf_iter_aux_info *aux, + struct seq_file *seq) +{ + seq_printf(seq, "map_id:\t%u\n", aux->map->id); +} + +int bpf_iter_map_fill_link_info(const struct bpf_iter_aux_info *aux, + struct bpf_link_info *info) +{ + info->iter.map.map_id = aux->map->id; + return 0; +} + DEFINE_BPF_ITER_FUNC(bpf_map_elem, struct bpf_iter_meta *meta, struct bpf_map *map, void *key, void *value) @@ -156,6 +169,8 @@ static const struct bpf_iter_reg bpf_map_elem_reg_info = { .target = "bpf_map_elem", .attach_target = bpf_iter_attach_map, .detach_target = bpf_iter_detach_map, + .show_fdinfo = bpf_iter_map_show_fdinfo, + .fill_link_info = bpf_iter_map_fill_link_info, .ctx_arg_info_size = 2, .ctx_arg_info = { { offsetof(struct bpf_iter__bpf_map_elem, key), diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c index b988f48153a4..281200dc0a01 100644 --- a/net/core/bpf_sk_storage.c +++ b/net/core/bpf_sk_storage.c @@ -1437,6 +1437,8 @@ static struct bpf_iter_reg bpf_sk_storage_map_reg_info = { .target = "bpf_sk_storage_map", .attach_target = bpf_iter_attach_map, .detach_target = bpf_iter_detach_map, + .show_fdinfo = bpf_iter_map_show_fdinfo, + .fill_link_info = bpf_iter_map_fill_link_info, .ctx_arg_info_size = 2, .ctx_arg_info = { { offsetof(struct bpf_iter__bpf_sk_storage_map, sk),