include/net/caif/cfpkt.h

   1 /*
   2  * Copyright (C) ST-Ericsson AB 2010
   3  * Author:      Sjur Brendeland/sjur.brandeland@stericsson.com
   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 /* Create a CAIF packet.
  20  * data Data to copy.
  21  * len Length of packet to be created
  22  * @return New packet.
  23  */
  24 struct cfpkt *cfpkt_create_uplink(const unsigned char *data, unsigned int len);
  25 /*
  26  * Destroy a CAIF Packet.
  27  * pkt Packet to be destoyed.
  28  */
  29 void cfpkt_destroy(struct cfpkt *pkt);
  30
  31 /*
  32  * Extract header from packet.
  33  *
  34  * pkt Packet to extract header data from.
  35  * data Pointer to copy the header data into.
  36  * len Length of head data to copy.
  37  * @return zero on success and error code upon failure
  38  */
  39 int cfpkt_extr_head(struct cfpkt *pkt, void *data, u16 len);
  40
  41 /*
  42  * Peek header from packet.
  43  * Reads data from packet without changing packet.
  44  *
  45  * pkt Packet to extract header data from.
  46  * data Pointer to copy the header data into.
  47  * len Length of head data to copy.
  48  * @return zero on success and error code upon failure
  49  */
  50 int cfpkt_peek_head(struct cfpkt *pkt, void *data, u16 len);
  51
  52 /*
  53  * Extract header from trailer (end of packet).
  54  *
  55  * pkt Packet to extract header data from.
  56  * data Pointer to copy the trailer data into.
  57  * len Length of header data to copy.
  58  * @return zero on success and error code upon failure
  59  */
  60 int cfpkt_extr_trail(struct cfpkt *pkt, void *data, u16 len);
  61
  62 /*
  63  * Add header to packet.
  64  *
  65  *
  66  * pkt Packet to add header data to.
  67  * data Pointer to data to copy into the header.
  68  * len Length of header data to copy.
  69  * @return zero on success and error code upon failure
  70  */
  71 int cfpkt_add_head(struct cfpkt *pkt, const void *data, u16 len);
  72
  73 /*
  74  * Add trailer to packet.
  75  *
  76  *
  77  * pkt Packet to add trailer data to.
  78  * data Pointer to data to copy into the trailer.
  79  * len Length of trailer data to copy.
  80  * @return zero on success and error code upon failure
  81  */
  82 int cfpkt_add_trail(struct cfpkt *pkt, const void *data, u16 len);
  83
  84 /*
  85  * Pad trailer on packet.
  86  * Moves data pointer in packet, no content copied.
  87  *
  88  * pkt Packet in which to pad trailer.
  89  * len Length of padding to add.
  90  * @return zero on success and error code upon failure
  91  */
  92 int cfpkt_pad_trail(struct cfpkt *pkt, u16 len);
  93
  94 /*
  95  * Add a single byte to packet body (tail).
  96  *
  97  * pkt Packet in which to add byte.
  98  * data Byte to add.
  99  * @return zero on success and error code upon failure
 100  */
 101 int cfpkt_addbdy(struct cfpkt *pkt, const u8 data);
 102
 103 /*
 104  * Add a data to packet body (tail).
 105  *
 106  * pkt Packet in which to add data.
 107  * data Pointer to data to copy into the packet body.
 108  * len Length of data to add.
 109  * @return zero on success and error code upon failure
 110  */
 111 int cfpkt_add_body(struct cfpkt *pkt, const void *data, u16 len);
 112
 113 /*
 114  * Checks whether there are more data to process in packet.
 115  * pkt Packet to check.
 116  * @return true if more data are available in packet false otherwise
 117  */
 118 bool cfpkt_more(struct cfpkt *pkt);
 119
 120 /*
 121  * Checks whether the packet is erroneous,
 122  * i.e. if it has been attempted to extract more data than available in packet
 123  * or writing more data than has been allocated in cfpkt_create().
 124  * pkt Packet to check.
 125  * @return true on error false otherwise
 126  */
 127 bool cfpkt_erroneous(struct cfpkt *pkt);
 128
 129 /*
 130  * Get the packet length.
 131  * pkt Packet to get length from.
 132  * @return Number of bytes in packet.
 133  */
 134 u16 cfpkt_getlen(struct cfpkt *pkt);
 135
 136 /*
 137  * Set the packet length, by adjusting the trailer pointer according to length.
 138  * pkt Packet to set length.
 139  * len Packet length.
 140  * @return Number of bytes in packet.
 141  */
 142 int cfpkt_setlen(struct cfpkt *pkt, u16 len);
 143
 144 /*
 145  * cfpkt_append - Appends a packet's data to another packet.
 146  * dstpkt:    Packet to append data into, WILL BE FREED BY THIS FUNCTION
 147  * addpkt:    Packet to be appended and automatically released,
 148  *            WILL BE FREED BY THIS FUNCTION.
 149  * expectlen: Packet's expected total length. This should be considered
 150  *            as a hint.
 151  * NB: Input packets will be destroyed after appending and cannot be used
 152  * after calling this function.
 153  * @return    The new appended packet.
 154  */
 155 struct cfpkt *cfpkt_append(struct cfpkt *dstpkt, struct cfpkt *addpkt,
 156                       u16 expectlen);
 157
 158 /*
 159  * cfpkt_split - Split a packet into two packets at the specified split point.
 160  * pkt: Packet to be split (will contain the first part of the data on exit)
 161  * pos: Position to split packet in two parts.
 162  * @return The new packet, containing the second part of the data.
 163  */
 164 struct cfpkt *cfpkt_split(struct cfpkt *pkt, u16 pos);
 165
 166 /*
 167  * Iteration function, iterates the packet buffers from start to end.
 168  *
 169  * Checksum iteration function used to iterate buffers
 170  * (we may have packets consisting of a chain of buffers)
 171  * pkt:       Packet to calculate checksum for
 172  * iter_func: Function pointer to iteration function
 173  * chks:      Checksum calculated so far.
 174  * buf:       Pointer to the buffer to checksum
 175  * len:       Length of buf.
 176  * data:      Initial checksum value.
 177  * @return    Checksum of buffer.
 178  */
 179
 180 u16 cfpkt_iterate(struct cfpkt *pkt,
 181                 u16 (*iter_func)(u16 chks, void *buf, u16 len),
 182                 u16 data);
 183
 184 /* Append by giving user access to packet buffer
 185  * cfpkt Packet to append to
 186  * buf Buffer inside pkt that user shall copy data into
 187  * buflen Length of buffer and number of bytes added to packet
 188  * @return 0 on error, 1 on success
 189  */
 190 int cfpkt_raw_append(struct cfpkt *cfpkt, void **buf, unsigned int buflen);
 191
 192 /* Extract by giving user access to packet buffer
 193  * cfpkt Packet to extract from
 194  * buf Buffer inside pkt that user shall copy data from
 195  * buflen Length of buffer and number of bytes removed from packet
 196  * @return 0 on error, 1 on success
 197  */
 198 int cfpkt_raw_extract(struct cfpkt *cfpkt, void **buf, unsigned int buflen);
 199
 200 /* Map from a "native" packet (e.g. Linux Socket Buffer) to a CAIF packet.
 201  *  dir - Direction indicating whether this packet is to be sent or received.
 202  *  nativepkt  - The native packet to be transformed to a CAIF packet
 203  *  @return The mapped CAIF Packet CFPKT.
 204  */
 205 struct cfpkt *cfpkt_fromnative(enum caif_direction dir, void *nativepkt);
 206
 207 /* Map from a CAIF packet to a "native" packet (e.g. Linux Socket Buffer).
 208  *  pkt  - The CAIF packet to be transformed into a "native" packet.
 209  *  @return The native packet transformed from a CAIF packet.
 210  */
 211 void *cfpkt_tonative(struct cfpkt *pkt);
 212
 213 /*
 214  * Insert a packet in the packet queue.
 215  * pktq Packet queue to insert into
 216  * pkt Packet to be inserted in queue
 217  * prio Priority of packet
 218  */
 219 void cfpkt_queue(struct cfpktq *pktq, struct cfpkt *pkt,
 220                  unsigned short prio);
 221
 222 /*
 223  * Remove a packet from the packet queue.
 224  * pktq Packet queue to fetch packets from.
 225  * @return Dequeued packet.
 226  */
 227 struct cfpkt *cfpkt_dequeue(struct cfpktq *pktq);
 228
 229 /*
 230  * Peek into a packet from the packet queue.
 231  * pktq Packet queue to fetch packets from.
 232  * @return Peeked packet.
 233  */
 234 struct cfpkt *cfpkt_qpeek(struct cfpktq *pktq);
 235
 236 /*
 237  * Initiates the packet queue.
 238  * @return Pointer to new packet queue.
 239  */
 240 struct cfpktq *cfpktq_create(void);
 241
 242 /*
 243  * Get the number of packets in the queue.
 244  * pktq Packet queue to fetch count from.
 245  * @return Number of packets in queue.
 246  */
 247 int cfpkt_qcount(struct cfpktq *pktq);
 248
 249 /*
 250  * Put content of packet into buffer for debuging purposes.
 251  * pkt Packet to copy data from
 252  * buf Buffer to copy data into
 253  * buflen Length of data to copy
 254  * @return Pointer to copied data
 255  */
 256 char *cfpkt_log_pkt(struct cfpkt *pkt, char *buf, int buflen);
 257
 258 /*
 259  * Clones a packet and releases the original packet.
 260  * This is used for taking ownership of a packet e.g queueing.
 261  * pkt Packet to clone and release.
 262  * @return Cloned packet.
 263  */
 264 struct cfpkt *cfpkt_clone_release(struct cfpkt *pkt);
 265
 266
 267 /*
 268  * Returns packet information for a packet.
 269  * pkt Packet to get info from;
 270  * @return Packet information
 271  */
 272 struct caif_payload_info *cfpkt_info(struct cfpkt *pkt);
 273 /*! @} */
 274 #endif                          /* CFPKT_H_ */