sync: auto-generate latest BPF helpers

Latest changes to BPF helper definitions.

src/bpf_helper_defs.h

@@ -1146,8 +1146,8 @@ static long (*bpf_probe_read_str)(void *dst, __u32 size, const void *unsafe_ptr)
  * 	identifier that can be assumed unique.
  *
  * Returns
- * 	A 8-byte long non-decreasing number on success, or 0 if the
- * 	socket field is missing inside *skb*.
+ * 	A 8-byte long unique number on success, or 0 if the socket
+ * 	field is missing inside *skb*.
  */
 static __u64 (*bpf_get_socket_cookie)(void *ctx) = (void *) 46;
 
@@ -1799,6 +1799,9 @@ static long (*bpf_skb_load_bytes_relative)(const void *skb, __u32 offset, void *
  * 	*   0 on success (packet is forwarded, nexthop neighbor exists)
  * 	* > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the
  * 	  packet is not forwarded or needs assist from full stack
+ *
+ * 	If lookup fails with BPF_FIB_LKUP_RET_FRAG_NEEDED, then the MTU
+ * 	was exceeded and output params->mtu_result contains the MTU.
  */
 static long (*bpf_fib_lookup)(void *ctx, struct bpf_fib_lookup *params, int plen, __u32 flags) = (void *) 69;
 
@@ -3731,4 +3734,102 @@ static long (*bpf_ima_inode_hash)(struct inode *inode, void *dst, __u32 size) =
  */
 static struct socket *(*bpf_sock_from_file)(struct file *file) = (void *) 162;
 
+/*
+ * bpf_check_mtu
+ *
+ * 	Check ctx packet size against exceeding MTU of net device (based
+ * 	on *ifindex*).  This helper will likely be used in combination
+ * 	with helpers that adjust/change the packet size.
+ *
+ * 	The argument *len_diff* can be used for querying with a planned
+ * 	size change. This allows to check MTU prior to changing packet
+ * 	ctx. Providing an *len_diff* adjustment that is larger than the
+ * 	actual packet size (resulting in negative packet size) will in
+ * 	principle not exceed the MTU, why it is not considered a
+ * 	failure.  Other BPF-helpers are needed for performing the
+ * 	planned size change, why the responsability for catch a negative
+ * 	packet size belong in those helpers.
+ *
+ * 	Specifying *ifindex* zero means the MTU check is performed
+ * 	against the current net device.  This is practical if this isn't
+ * 	used prior to redirect.
+ *
+ * 	The Linux kernel route table can configure MTUs on a more
+ * 	specific per route level, which is not provided by this helper.
+ * 	For route level MTU checks use the **bpf_fib_lookup**\ ()
+ * 	helper.
+ *
+ * 	*ctx* is either **struct xdp_md** for XDP programs or
+ * 	**struct sk_buff** for tc cls_act programs.
+ *
+ * 	The *flags* argument can be a combination of one or more of the
+ * 	following values:
+ *
+ * 	**BPF_MTU_CHK_SEGS**
+ * 		This flag will only works for *ctx* **struct sk_buff**.
+ * 		If packet context contains extra packet segment buffers
+ * 		(often knows as GSO skb), then MTU check is harder to
+ * 		check at this point, because in transmit path it is
+ * 		possible for the skb packet to get re-segmented
+ * 		(depending on net device features).  This could still be
+ * 		a MTU violation, so this flag enables performing MTU
+ * 		check against segments, with a different violation
+ * 		return code to tell it apart. Check cannot use len_diff.
+ *
+ * 	On return *mtu_len* pointer contains the MTU value of the net
+ * 	device.  Remember the net device configured MTU is the L3 size,
+ * 	which is returned here and XDP and TX length operate at L2.
+ * 	Helper take this into account for you, but remember when using
+ * 	MTU value in your BPF-code.  On input *mtu_len* must be a valid
+ * 	pointer and be initialized (to zero), else verifier will reject
+ * 	BPF program.
+ *
+ *
+ * Returns
+ * 	* 0 on success, and populate MTU value in *mtu_len* pointer.
+ *
+ * 	* < 0 if any input argument is invalid (*mtu_len* not updated)
+ *
+ * 	MTU violations return positive values, but also populate MTU
+ * 	value in *mtu_len* pointer, as this can be needed for
+ * 	implementing PMTU handing:
+ *
+ * 	* **BPF_MTU_CHK_RET_FRAG_NEEDED**
+ * 	* **BPF_MTU_CHK_RET_SEGS_TOOBIG**
+ */
+static long (*bpf_check_mtu)(void *ctx, __u32 ifindex, __u32 *mtu_len, __s32 len_diff, __u64 flags) = (void *) 163;
+
+/*
+ * bpf_for_each_map_elem
+ *
+ * 	For each element in **map**, call **callback_fn** function with
+ * 	**map**, **callback_ctx** and other map-specific parameters.
+ * 	The **callback_fn** should be a static function and
+ * 	the **callback_ctx** should be a pointer to the stack.
+ * 	The **flags** is used to control certain aspects of the helper.
+ * 	Currently, the **flags** must be 0.
+ *
+ * 	The following are a list of supported map types and their
+ * 	respective expected callback signatures:
+ *
+ * 	BPF_MAP_TYPE_HASH, BPF_MAP_TYPE_PERCPU_HASH,
+ * 	BPF_MAP_TYPE_LRU_HASH, BPF_MAP_TYPE_LRU_PERCPU_HASH,
+ * 	BPF_MAP_TYPE_ARRAY, BPF_MAP_TYPE_PERCPU_ARRAY
+ *
+ * 	long (\*callback_fn)(struct bpf_map \*map, const void \*key, void \*value, void \*ctx);
+ *
+ * 	For per_cpu maps, the map_value is the value on the cpu where the
+ * 	bpf_prog is running.
+ *
+ * 	If **callback_fn** return 0, the helper will continue to the next
+ * 	element. If return value is 1, the helper will skip the rest of
+ * 	elements and return. Other return values are not used now.
+ *
+ *
+ * Returns
+ * 	The number of traversed map elements for success, **-EINVAL** for
+ * 	invalid **flags**.
+ */
+static long (*bpf_for_each_map_elem)(void *map, void *callback_fn, void *callback_ctx, __u64 flags) = (void *) 164;
+