bpf: sync bpf.h to tools/

Sync cgroup storage related changes:
1) new BPF_MAP_TYPE_CGROUP_STORAGE map type
2) struct bpf_cgroup_sotrage_key definition
3) get_local_storage() helper

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/include/uapi/linux/bpf.h

@@ -75,6 +75,11 @@ struct bpf_lpm_trie_key {
 	__u8	data[0];	/* Arbitrary size */
 };
 
+struct bpf_cgroup_storage_key {
+	__u64	cgroup_inode_id;	/* cgroup inode id */
+	__u32	attach_type;		/* program attach type */
+};
+
 /* BPF syscall commands, see bpf(2) man-page for details. */
 enum bpf_cmd {
 	BPF_MAP_CREATE,
@@ -120,6 +125,7 @@ enum bpf_map_type {
 	BPF_MAP_TYPE_CPUMAP,
 	BPF_MAP_TYPE_XSKMAP,
 	BPF_MAP_TYPE_SOCKHASH,
+	BPF_MAP_TYPE_CGROUP_STORAGE,
 };
 
 enum bpf_prog_type {
@@ -2089,6 +2095,24 @@ union bpf_attr {
  * 	Return
  * 		A 64-bit integer containing the current cgroup id based
  * 		on the cgroup within which the current task is running.
+ *
+ * void* get_local_storage(void *map, u64 flags)
+ *	Description
+ *		Get the pointer to the local storage area.
+ *		The type and the size of the local storage is defined
+ *		by the *map* argument.
+ *		The *flags* meaning is specific for each map type,
+ *		and has to be 0 for cgroup local storage.
+ *
+ *		Depending on the bpf program type, a local storage area
+ *		can be shared between multiple instances of the bpf program,
+ *		running simultaneously.
+ *
+ *		A user should care about the synchronization by himself.
+ *		For example, by using the BPF_STX_XADD instruction to alter
+ *		the shared data.
+ *	Return
+ *		Pointer to the local storage area.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -2171,7 +2195,8 @@ union bpf_attr {
 	FN(rc_repeat),			\
 	FN(rc_keydown),			\
 	FN(skb_cgroup_id),		\
-	FN(get_current_cgroup_id),
+	FN(get_current_cgroup_id),	\
+	FN(get_local_storage),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call