xref: /linux/include/linux/if_rmnet.h (revision 9410645520e9b820069761f3450ef6661418e279)
1 /* SPDX-License-Identifier: GPL-2.0-only
2  * Copyright (c) 2013-2019, 2021 The Linux Foundation. All rights reserved.
3  */
4 
5 #ifndef _LINUX_IF_RMNET_H_
6 #define _LINUX_IF_RMNET_H_
7 
8 #include <linux/types.h>
9 
10 struct rmnet_map_header {
11 	u8 flags;			/* MAP_CMD_FLAG, MAP_PAD_LEN_MASK */
12 	u8 mux_id;
13 	__be16 pkt_len;			/* Length of packet, including pad */
14 }  __aligned(1);
15 
16 /* rmnet_map_header flags field:
17  *  PAD_LEN:	  number of pad bytes following packet data
18  *  CMD:	  1 = packet contains a MAP command; 0 = packet contains data
19  *  NEXT_HEADER: 1 = packet contains V5 CSUM header 0 = no V5 CSUM header
20  */
21 #define MAP_PAD_LEN_MASK		GENMASK(5, 0)
22 #define MAP_NEXT_HEADER_FLAG		BIT(6)
23 #define MAP_CMD_FLAG			BIT(7)
24 
25 struct rmnet_map_dl_csum_trailer {
26 	u8 reserved1;
27 	u8 flags;			/* MAP_CSUM_DL_VALID_FLAG */
28 	__be16 csum_start_offset;
29 	__be16 csum_length;
30 	__sum16 csum_value;
31 } __aligned(1);
32 
33 /* rmnet_map_dl_csum_trailer flags field:
34  *  VALID:	1 = checksum and length valid; 0 = ignore them
35  */
36 #define MAP_CSUM_DL_VALID_FLAG		BIT(0)
37 
38 struct rmnet_map_ul_csum_header {
39 	__be16 csum_start_offset;
40 	__be16 csum_info;		/* MAP_CSUM_UL_* */
41 } __aligned(1);
42 
43 /* csum_info field:
44  *  OFFSET:	where (offset in bytes) to insert computed checksum
45  *  UDP:	1 = UDP checksum (zero checksum means no checksum)
46  *  ENABLED:	1 = checksum computation requested
47  */
48 #define MAP_CSUM_UL_OFFSET_MASK		GENMASK(13, 0)
49 #define MAP_CSUM_UL_UDP_FLAG		BIT(14)
50 #define MAP_CSUM_UL_ENABLED_FLAG	BIT(15)
51 
52 /* MAP CSUM headers */
53 struct rmnet_map_v5_csum_header {
54 	u8 header_info;
55 	u8 csum_info;
56 	__be16 reserved;
57 } __aligned(1);
58 
59 /* v5 header_info field
60  * NEXT_HEADER: represents whether there is any next header
61  * HEADER_TYPE: represents the type of this header
62  *
63  * csum_info field
64  * CSUM_VALID_OR_REQ:
65  * 1 = for UL, checksum computation is requested.
66  * 1 = for DL, validated the checksum and has found it valid
67  */
68 
69 #define MAPV5_HDRINFO_NXT_HDR_FLAG	BIT(0)
70 #define MAPV5_HDRINFO_HDR_TYPE_FMASK	GENMASK(7, 1)
71 #define MAPV5_CSUMINFO_VALID_FLAG	BIT(7)
72 
73 #define RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD 2
74 #endif /* !(_LINUX_IF_RMNET_H_) */
75