xref: /openbmc/linux/include/net/caif/cfpkt.h (revision c8ec3743)
1 /*
2  * Copyright (C) ST-Ericsson AB 2010
3  * Author:	Sjur Brendeland
4  * License terms: GNU General Public License (GPL) version 2
5  */
6 
7 #ifndef CFPKT_H_
8 #define CFPKT_H_
9 #include <net/caif/caif_layer.h>
10 #include <linux/types.h>
11 struct cfpkt;
12 
13 /* Create a CAIF packet.
14  * len: Length of packet to be created
15  * @return New packet.
16  */
17 struct cfpkt *cfpkt_create(u16 len);
18 
19 /*
20  * Destroy a CAIF Packet.
21  * pkt Packet to be destoyed.
22  */
23 void 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  */
33 int cfpkt_extr_head(struct cfpkt *pkt, void *data, u16 len);
34 
35 static inline u8 cfpkt_extr_head_u8(struct cfpkt *pkt)
36 {
37 	u8 tmp;
38 
39 	cfpkt_extr_head(pkt, &tmp, 1);
40 
41 	return tmp;
42 }
43 
44 static inline u16 cfpkt_extr_head_u16(struct cfpkt *pkt)
45 {
46 	__le16 tmp;
47 
48 	cfpkt_extr_head(pkt, &tmp, 2);
49 
50 	return le16_to_cpu(tmp);
51 }
52 
53 static inline u32 cfpkt_extr_head_u32(struct cfpkt *pkt)
54 {
55 	__le32 tmp;
56 
57 	cfpkt_extr_head(pkt, &tmp, 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  */
71 int 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  */
81 int 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  */
92 int 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  */
103 int 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  */
113 int 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  */
122 int 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  */
132 int 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  */
139 bool 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  */
148 bool 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  */
155 u16 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  */
163 int 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  */
176 struct 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  */
185 struct 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 
201 int 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  */
210 struct 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  */
216 void *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  */
223 struct 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  */
230 void cfpkt_set_prio(struct cfpkt *pkt, int prio);
231 
232 #endif				/* CFPKT_H_ */
233