From bd5f5f4ecb78e2698dad655645b6d6a2f7012a8c Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Mon, 5 Jun 2017 12:15:50 -0700 Subject: bpf: Add BPF_MAP_GET_FD_BY_ID Add BPF_MAP_GET_FD_BY_ID command to allow user to get a fd from a bpf_map's ID. bpf_map_inc_not_zero() is added and is called with map_idr_lock held. __bpf_map_put() is also added which has the 'bool do_idr_lock' param to decide if the map_idr_lock should be acquired when freeing the map->id. In the error path of bpf_map_inc_not_zero(), it may have to call __bpf_map_put(map, false) which does not need to take the map_idr_lock when freeing the map->id. It is currently limited to CAP_SYS_ADMIN which we can consider to lift it in followup patches. Signed-off-by: Martin KaFai Lau Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- include/uapi/linux/bpf.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/uapi/linux/bpf.h') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index d70cfed19d5e..dd23f47ff00c 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -85,6 +85,7 @@ enum bpf_cmd { BPF_PROG_GET_NEXT_ID, BPF_MAP_GET_NEXT_ID, BPF_PROG_GET_FD_BY_ID, + BPF_MAP_GET_FD_BY_ID, }; enum bpf_map_type { @@ -217,6 +218,7 @@ union bpf_attr { union { __u32 start_id; __u32 prog_id; + __u32 map_id; }; __u32 next_id; }; -- cgit v1.2.3-55-g7522