bpf: fix up uapi helper description and sync bpf header with tools

Minor markup fixup from bpf-next into net-next merge in the BPF helper
description of bpf_sk_lookup_tcp() and bpf_sk_lookup_udp(). Also sync
up the copy of bpf.h from tooling infrastructure.

Signed-off-by: Daniel Borkmann <[email protected]>
Reviewed-by: Quentin Monnet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: borkmann

include/uapi/linux/bpf.h

@@ -2218,9 +2218,9 @@ union bpf_attr {
  *		This helper is available only if the kernel was compiled with
  *		**CONFIG_NET** configuration option.
  *	Return
- *		Pointer to *struct bpf_sock*, or NULL in case of failure.
- *		For sockets with reuseport option, the *struct bpf_sock*
- *		result is from reuse->socks[] using the hash of the tuple.
+ *		Pointer to **struct bpf_sock**, or **NULL** in case of failure.
+ *		For sockets with reuseport option, the **struct bpf_sock**
+ *		result is from **reuse->socks**\ [] using the hash of the tuple.
  *
  * struct bpf_sock *bpf_sk_lookup_udp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
  *	Description
@@ -2254,9 +2254,9 @@ union bpf_attr {
  *		This helper is available only if the kernel was compiled with
  *		**CONFIG_NET** configuration option.
  *	Return
- *		Pointer to *struct bpf_sock*, or NULL in case of failure.
- *		For sockets with reuseport option, the *struct bpf_sock*
- *		result is from reuse->socks[] using the hash of the tuple.
+ *		Pointer to **struct bpf_sock**, or **NULL** in case of failure.
+ *		For sockets with reuseport option, the **struct bpf_sock**
+ *		result is from **reuse->socks**\ [] using the hash of the tuple.
  *
  * int bpf_sk_release(struct bpf_sock *sock)
  *	Description

tools/include/uapi/linux/bpf.h

@@ -502,18 +502,6 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_map_pop_elem(struct bpf_map *map, void *value)
- * 	Description
- * 		Pop an element from *map*.
- * Return
- * 		0 on success, or a negative error in case of failure.
- *
- * int bpf_map_peek_elem(struct bpf_map *map, void *value)
- * 	Description
- * 		Get an element from *map* without removing it.
- * Return
- * 		0 on success, or a negative error in case of failure.
- *
  * int bpf_probe_read(void *dst, u32 size, const void *src)
  * 	Description
  * 		For tracing programs, safely attempt to read *size* bytes from
@@ -1937,9 +1925,9 @@ union bpf_attr {
  *		is set to metric from route (IPv4/IPv6 only), and ifindex
  *		is set to the device index of the nexthop from the FIB lookup.
  *
- *             *plen* argument is the size of the passed in struct.
- *             *flags* argument can be a combination of one or more of the
- *             following values:
+ *		*plen* argument is the size of the passed in struct.
+ *		*flags* argument can be a combination of one or more of the
+ *		following values:
  *
  *		**BPF_FIB_LOOKUP_DIRECT**
  *			Do a direct table lookup vs full lookup using FIB
@@ -1948,9 +1936,9 @@ union bpf_attr {
  *			Perform lookup from an egress perspective (default is
  *			ingress).
  *
- *             *ctx* is either **struct xdp_md** for XDP programs or
- *             **struct sk_buff** tc cls_act programs.
- *     Return
+ *		*ctx* is either **struct xdp_md** for XDP programs or
+ *		**struct sk_buff** tc cls_act programs.
+ *	Return
  *		* < 0 if any input argument is invalid
  *		*   0 on success (packet is forwarded, nexthop neighbor exists)
  *		* > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the
@@ -2095,8 +2083,8 @@ union bpf_attr {
  *		translated to a keycode using the rc keymap, and reported as
  *		an input key down event. After a period a key up event is
  *		generated. This period can be extended by calling either
- *		**bpf_rc_keydown** () again with the same values, or calling
- *		**bpf_rc_repeat** ().
+ *		**bpf_rc_keydown**\ () again with the same values, or calling
+ *		**bpf_rc_repeat**\ ().
  *
  *		Some protocols include a toggle bit, in case the button	was
  *		released and pressed again between consecutive scancodes.
@@ -2179,29 +2167,30 @@ union bpf_attr {
  *		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,
+ *		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
+ *		For example, by using the **BPF_STX_XADD** instruction to alter
  *		the shared data.
  *	Return
- *		Pointer to the local storage area.
+ *		A pointer to the local storage area.
  *
  * int bpf_sk_select_reuseport(struct sk_reuseport_md *reuse, struct bpf_map *map, void *key, u64 flags)
  *	Description
- *		Select a SO_REUSEPORT sk from a	BPF_MAP_TYPE_REUSEPORT_ARRAY map
- *		It checks the selected sk is matching the incoming
- *		request in the skb.
+ *		Select a **SO_REUSEPORT** socket from a
+ *		**BPF_MAP_TYPE_REUSEPORT_ARRAY** *map*.
+ *		It checks the selected socket is matching the incoming
+ *		request in the socket buffer.
  *	Return
  *		0 on success, or a negative error in case of failure.
  *
  * struct bpf_sock *bpf_sk_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
  *	Description
  *		Look for TCP socket matching *tuple*, optionally in a child
  *		network namespace *netns*. The return value must be checked,
- *		and if non-NULL, released via **bpf_sk_release**\ ().
+ *		and if non-**NULL**, released via **bpf_sk_release**\ ().
  *
  *		The *ctx* should point to the context of the program, such as
  *		the skb or socket (depending on the hook in use). This is used
@@ -2229,15 +2218,15 @@ union bpf_attr {
  *		This helper is available only if the kernel was compiled with
  *		**CONFIG_NET** configuration option.
  *	Return
- *		Pointer to *struct bpf_sock*, or NULL in case of failure.
- *		For sockets with reuseport option, the *struct bpf_sock*
- *		result is from reuse->socks[] using the hash of the tuple.
+ *		Pointer to **struct bpf_sock**, or **NULL** in case of failure.
+ *		For sockets with reuseport option, the **struct bpf_sock**
+ *		result is from **reuse->socks**\ [] using the hash of the tuple.
  *
  * struct bpf_sock *bpf_sk_lookup_udp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
  *	Description
  *		Look for UDP socket matching *tuple*, optionally in a child
  *		network namespace *netns*. The return value must be checked,
- *		and if non-NULL, released via **bpf_sk_release**\ ().
+ *		and if non-**NULL**, released via **bpf_sk_release**\ ().
  *
  *		The *ctx* should point to the context of the program, such as
  *		the skb or socket (depending on the hook in use). This is used
@@ -2265,42 +2254,54 @@ union bpf_attr {
  *		This helper is available only if the kernel was compiled with
  *		**CONFIG_NET** configuration option.
  *	Return
- *		Pointer to *struct bpf_sock*, or NULL in case of failure.
- *		For sockets with reuseport option, the *struct bpf_sock*
- *		result is from reuse->socks[] using the hash of the tuple.
+ *		Pointer to **struct bpf_sock**, or **NULL** in case of failure.
+ *		For sockets with reuseport option, the **struct bpf_sock**
+ *		result is from **reuse->socks**\ [] using the hash of the tuple.
  *
- * int bpf_sk_release(struct bpf_sock *sk)
+ * int bpf_sk_release(struct bpf_sock *sock)
  *	Description
- *		Release the reference held by *sock*. *sock* must be a non-NULL
- *		pointer that was returned from bpf_sk_lookup_xxx\ ().
+ *		Release the reference held by *sock*. *sock* must be a
+ *		non-**NULL** pointer that was returned from
+ *		**bpf_sk_lookup_xxx**\ ().
  *	Return
  *		0 on success, or a negative error in case of failure.
  *
+ * int bpf_map_pop_elem(struct bpf_map *map, void *value)
+ * 	Description
+ * 		Pop an element from *map*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_map_peek_elem(struct bpf_map *map, void *value)
+ * 	Description
+ * 		Get an element from *map* without removing it.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
  * int bpf_msg_push_data(struct sk_buff *skb, u32 start, u32 len, u64 flags)
  *	Description
- *		For socket policies, insert *len* bytes into msg at offset
+ *		For socket policies, insert *len* bytes into *msg* at offset
  *		*start*.
  *
  *		If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a
- *		*msg* it may want to insert metadata or options into the msg.
+ *		*msg* it may want to insert metadata or options into the *msg*.
  *		This can later be read and used by any of the lower layer BPF
  *		hooks.
  *
  *		This helper may fail if under memory pressure (a malloc
  *		fails) in these cases BPF programs will get an appropriate
  *		error and BPF programs will need to handle them.
- *
  *	Return
  *		0 on success, or a negative error in case of failure.
  *
  * int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 pop, u64 flags)
- *	 Description
+ *	Description
  *		Will remove *pop* bytes from a *msg* starting at byte *start*.
  *		This may result in **ENOMEM** errors under certain situations if
  *		an allocation and copy are required due to a full ring buffer.
  *		However, the helper will try to avoid doing the allocation
  *		if possible. Other errors can occur if input parameters are
- *		invalid either due to *start* byte not being valid part of msg
+ *		invalid either due to *start* byte not being valid part of *msg*
  *		payload and/or *pop* value being to large.
  *	Return
  *		0 on success, or a negative error in case of failure.