1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) ST-Ericsson AB 2010
4 * Author: Sjur Brendeland
5 */
6
7#ifndef CFPKT_H_
8#define CFPKT_H_
9#include <net/caif/caif_layer.h>
10#include <linux/types.h>
11struct cfpkt;
12
13/* Create a CAIF packet.
14 * len: Length of packet to be created
15 * @return New packet.
16 */
17struct cfpkt *cfpkt_create(u16 len);
18
19/*
20 * Destroy a CAIF Packet.
21 * pkt Packet to be destoyed.
22 */
23void cfpkt_destroy(struct cfpkt *pkt);
24
25/*
26 * Extract header from packet.
27 *
28 * pkt Packet to extract header data from.
29 * data Pointer to copy the header data into.
30 * len Length of head data to copy.
31 * @return zero on success and error code upon failure
32 */
33int cfpkt_extr_head(struct cfpkt *pkt, void *data, u16 len);
34
35static inline u8 cfpkt_extr_head_u8(struct cfpkt *pkt)
36{
37 u8 tmp;
38
39 cfpkt_extr_head(pkt, data: &tmp, len: 1);
40
41 return tmp;
42}
43
44static inline u16 cfpkt_extr_head_u16(struct cfpkt *pkt)
45{
46 __le16 tmp;
47
48 cfpkt_extr_head(pkt, data: &tmp, len: 2);
49
50 return le16_to_cpu(tmp);
51}
52
53static inline u32 cfpkt_extr_head_u32(struct cfpkt *pkt)
54{
55 __le32 tmp;
56
57 cfpkt_extr_head(pkt, data: &tmp, len: 4);
58
59 return le32_to_cpu(tmp);
60}
61
62/*
63 * Peek header from packet.
64 * Reads data from packet without changing packet.
65 *
66 * pkt Packet to extract header data from.
67 * data Pointer to copy the header data into.
68 * len Length of head data to copy.
69 * @return zero on success and error code upon failure
70 */
71int cfpkt_peek_head(struct cfpkt *pkt, void *data, u16 len);
72
73/*
74 * Extract header from trailer (end of packet).
75 *
76 * pkt Packet to extract header data from.
77 * data Pointer to copy the trailer data into.
78 * len Length of header data to copy.
79 * @return zero on success and error code upon failure
80 */
81int cfpkt_extr_trail(struct cfpkt *pkt, void *data, u16 len);
82
83/*
84 * Add header to packet.
85 *
86 *
87 * pkt Packet to add header data to.
88 * data Pointer to data to copy into the header.
89 * len Length of header data to copy.
90 * @return zero on success and error code upon failure
91 */
92int cfpkt_add_head(struct cfpkt *pkt, const void *data, u16 len);
93
94/*
95 * Add trailer to packet.
96 *
97 *
98 * pkt Packet to add trailer data to.
99 * data Pointer to data to copy into the trailer.
100 * len Length of trailer data to copy.
101 * @return zero on success and error code upon failure
102 */
103int cfpkt_add_trail(struct cfpkt *pkt, const void *data, u16 len);
104
105/*
106 * Pad trailer on packet.
107 * Moves data pointer in packet, no content copied.
108 *
109 * pkt Packet in which to pad trailer.
110 * len Length of padding to add.
111 * @return zero on success and error code upon failure
112 */
113int cfpkt_pad_trail(struct cfpkt *pkt, u16 len);
114
115/*
116 * Add a single byte to packet body (tail).
117 *
118 * pkt Packet in which to add byte.
119 * data Byte to add.
120 * @return zero on success and error code upon failure
121 */
122int cfpkt_addbdy(struct cfpkt *pkt, const u8 data);
123
124/*
125 * Add a data to packet body (tail).
126 *
127 * pkt Packet in which to add data.
128 * data Pointer to data to copy into the packet body.
129 * len Length of data to add.
130 * @return zero on success and error code upon failure
131 */
132int cfpkt_add_body(struct cfpkt *pkt, const void *data, u16 len);
133
134/*
135 * Checks whether there are more data to process in packet.
136 * pkt Packet to check.
137 * @return true if more data are available in packet false otherwise
138 */
139bool cfpkt_more(struct cfpkt *pkt);
140
141/*
142 * Checks whether the packet is erroneous,
143 * i.e. if it has been attempted to extract more data than available in packet
144 * or writing more data than has been allocated in cfpkt_create().
145 * pkt Packet to check.
146 * @return true on error false otherwise
147 */
148bool cfpkt_erroneous(struct cfpkt *pkt);
149
150/*
151 * Get the packet length.
152 * pkt Packet to get length from.
153 * @return Number of bytes in packet.
154 */
155u16 cfpkt_getlen(struct cfpkt *pkt);
156
157/*
158 * Set the packet length, by adjusting the trailer pointer according to length.
159 * pkt Packet to set length.
160 * len Packet length.
161 * @return Number of bytes in packet.
162 */
163int cfpkt_setlen(struct cfpkt *pkt, u16 len);
164
165/*
166 * cfpkt_append - Appends a packet's data to another packet.
167 * dstpkt: Packet to append data into, WILL BE FREED BY THIS FUNCTION
168 * addpkt: Packet to be appended and automatically released,
169 * WILL BE FREED BY THIS FUNCTION.
170 * expectlen: Packet's expected total length. This should be considered
171 * as a hint.
172 * NB: Input packets will be destroyed after appending and cannot be used
173 * after calling this function.
174 * @return The new appended packet.
175 */
176struct cfpkt *cfpkt_append(struct cfpkt *dstpkt, struct cfpkt *addpkt,
177 u16 expectlen);
178
179/*
180 * cfpkt_split - Split a packet into two packets at the specified split point.
181 * pkt: Packet to be split (will contain the first part of the data on exit)
182 * pos: Position to split packet in two parts.
183 * @return The new packet, containing the second part of the data.
184 */
185struct cfpkt *cfpkt_split(struct cfpkt *pkt, u16 pos);
186
187/*
188 * Iteration function, iterates the packet buffers from start to end.
189 *
190 * Checksum iteration function used to iterate buffers
191 * (we may have packets consisting of a chain of buffers)
192 * pkt: Packet to calculate checksum for
193 * iter_func: Function pointer to iteration function
194 * chks: Checksum calculated so far.
195 * buf: Pointer to the buffer to checksum
196 * len: Length of buf.
197 * data: Initial checksum value.
198 * @return Checksum of buffer.
199 */
200
201int cfpkt_iterate(struct cfpkt *pkt,
202 u16 (*iter_func)(u16 chks, void *buf, u16 len),
203 u16 data);
204
205/* Map from a "native" packet (e.g. Linux Socket Buffer) to a CAIF packet.
206 * dir - Direction indicating whether this packet is to be sent or received.
207 * nativepkt - The native packet to be transformed to a CAIF packet
208 * @return The mapped CAIF Packet CFPKT.
209 */
210struct cfpkt *cfpkt_fromnative(enum caif_direction dir, void *nativepkt);
211
212/* Map from a CAIF packet to a "native" packet (e.g. Linux Socket Buffer).
213 * pkt - The CAIF packet to be transformed into a "native" packet.
214 * @return The native packet transformed from a CAIF packet.
215 */
216void *cfpkt_tonative(struct cfpkt *pkt);
217
218/*
219 * Returns packet information for a packet.
220 * pkt Packet to get info from;
221 * @return Packet information
222 */
223struct caif_payload_info *cfpkt_info(struct cfpkt *pkt);
224
225/** cfpkt_set_prio - set priority for a CAIF packet.
226 *
227 * @pkt: The CAIF packet to be adjusted.
228 * @prio: one of TC_PRIO_ constants.
229 */
230void cfpkt_set_prio(struct cfpkt *pkt, int prio);
231
232#endif /* CFPKT_H_ */
233

source code of linux/include/net/caif/cfpkt.h