linux/include/net/caif/cfpkt.h
Arnd Bergmann ce6289661b caif: reduce stack size with KASAN
When CONFIG_KASAN is set, we can use relatively large amounts of kernel
stack space:

net/caif/cfctrl.c:555:1: warning: the frame size of 1600 bytes is larger than 1280 bytes [-Wframe-larger-than=]

This adds convenience wrappers around cfpkt_extr_head(), which is responsible
for most of the stack growth. With those wrapper functions, gcc apparently
starts reusing the stack slots for each instance, thus avoiding the
problem.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 14:02:12 -05:00

233 lines
6.3 KiB
C

/*
* Copyright (C) ST-Ericsson AB 2010
* Author: Sjur Brendeland
* License terms: GNU General Public License (GPL) version 2
*/
#ifndef CFPKT_H_
#define CFPKT_H_
#include <net/caif/caif_layer.h>
#include <linux/types.h>
struct cfpkt;
/* Create a CAIF packet.
* len: Length of packet to be created
* @return New packet.
*/
struct cfpkt *cfpkt_create(u16 len);
/*
* Destroy a CAIF Packet.
* pkt Packet to be destoyed.
*/
void cfpkt_destroy(struct cfpkt *pkt);
/*
* Extract header from packet.
*
* pkt Packet to extract header data from.
* data Pointer to copy the header data into.
* len Length of head data to copy.
* @return zero on success and error code upon failure
*/
int cfpkt_extr_head(struct cfpkt *pkt, void *data, u16 len);
static inline u8 cfpkt_extr_head_u8(struct cfpkt *pkt)
{
u8 tmp;
cfpkt_extr_head(pkt, &tmp, 1);
return tmp;
}
static inline u16 cfpkt_extr_head_u16(struct cfpkt *pkt)
{
__le16 tmp;
cfpkt_extr_head(pkt, &tmp, 2);
return le16_to_cpu(tmp);
}
static inline u32 cfpkt_extr_head_u32(struct cfpkt *pkt)
{
__le32 tmp;
cfpkt_extr_head(pkt, &tmp, 4);
return le32_to_cpu(tmp);
}
/*
* Peek header from packet.
* Reads data from packet without changing packet.
*
* pkt Packet to extract header data from.
* data Pointer to copy the header data into.
* len Length of head data to copy.
* @return zero on success and error code upon failure
*/
int cfpkt_peek_head(struct cfpkt *pkt, void *data, u16 len);
/*
* Extract header from trailer (end of packet).
*
* pkt Packet to extract header data from.
* data Pointer to copy the trailer data into.
* len Length of header data to copy.
* @return zero on success and error code upon failure
*/
int cfpkt_extr_trail(struct cfpkt *pkt, void *data, u16 len);
/*
* Add header to packet.
*
*
* pkt Packet to add header data to.
* data Pointer to data to copy into the header.
* len Length of header data to copy.
* @return zero on success and error code upon failure
*/
int cfpkt_add_head(struct cfpkt *pkt, const void *data, u16 len);
/*
* Add trailer to packet.
*
*
* pkt Packet to add trailer data to.
* data Pointer to data to copy into the trailer.
* len Length of trailer data to copy.
* @return zero on success and error code upon failure
*/
int cfpkt_add_trail(struct cfpkt *pkt, const void *data, u16 len);
/*
* Pad trailer on packet.
* Moves data pointer in packet, no content copied.
*
* pkt Packet in which to pad trailer.
* len Length of padding to add.
* @return zero on success and error code upon failure
*/
int cfpkt_pad_trail(struct cfpkt *pkt, u16 len);
/*
* Add a single byte to packet body (tail).
*
* pkt Packet in which to add byte.
* data Byte to add.
* @return zero on success and error code upon failure
*/
int cfpkt_addbdy(struct cfpkt *pkt, const u8 data);
/*
* Add a data to packet body (tail).
*
* pkt Packet in which to add data.
* data Pointer to data to copy into the packet body.
* len Length of data to add.
* @return zero on success and error code upon failure
*/
int cfpkt_add_body(struct cfpkt *pkt, const void *data, u16 len);
/*
* Checks whether there are more data to process in packet.
* pkt Packet to check.
* @return true if more data are available in packet false otherwise
*/
bool cfpkt_more(struct cfpkt *pkt);
/*
* Checks whether the packet is erroneous,
* i.e. if it has been attempted to extract more data than available in packet
* or writing more data than has been allocated in cfpkt_create().
* pkt Packet to check.
* @return true on error false otherwise
*/
bool cfpkt_erroneous(struct cfpkt *pkt);
/*
* Get the packet length.
* pkt Packet to get length from.
* @return Number of bytes in packet.
*/
u16 cfpkt_getlen(struct cfpkt *pkt);
/*
* Set the packet length, by adjusting the trailer pointer according to length.
* pkt Packet to set length.
* len Packet length.
* @return Number of bytes in packet.
*/
int cfpkt_setlen(struct cfpkt *pkt, u16 len);
/*
* cfpkt_append - Appends a packet's data to another packet.
* dstpkt: Packet to append data into, WILL BE FREED BY THIS FUNCTION
* addpkt: Packet to be appended and automatically released,
* WILL BE FREED BY THIS FUNCTION.
* expectlen: Packet's expected total length. This should be considered
* as a hint.
* NB: Input packets will be destroyed after appending and cannot be used
* after calling this function.
* @return The new appended packet.
*/
struct cfpkt *cfpkt_append(struct cfpkt *dstpkt, struct cfpkt *addpkt,
u16 expectlen);
/*
* cfpkt_split - Split a packet into two packets at the specified split point.
* pkt: Packet to be split (will contain the first part of the data on exit)
* pos: Position to split packet in two parts.
* @return The new packet, containing the second part of the data.
*/
struct cfpkt *cfpkt_split(struct cfpkt *pkt, u16 pos);
/*
* Iteration function, iterates the packet buffers from start to end.
*
* Checksum iteration function used to iterate buffers
* (we may have packets consisting of a chain of buffers)
* pkt: Packet to calculate checksum for
* iter_func: Function pointer to iteration function
* chks: Checksum calculated so far.
* buf: Pointer to the buffer to checksum
* len: Length of buf.
* data: Initial checksum value.
* @return Checksum of buffer.
*/
int cfpkt_iterate(struct cfpkt *pkt,
u16 (*iter_func)(u16 chks, void *buf, u16 len),
u16 data);
/* Map from a "native" packet (e.g. Linux Socket Buffer) to a CAIF packet.
* dir - Direction indicating whether this packet is to be sent or received.
* nativepkt - The native packet to be transformed to a CAIF packet
* @return The mapped CAIF Packet CFPKT.
*/
struct cfpkt *cfpkt_fromnative(enum caif_direction dir, void *nativepkt);
/* Map from a CAIF packet to a "native" packet (e.g. Linux Socket Buffer).
* pkt - The CAIF packet to be transformed into a "native" packet.
* @return The native packet transformed from a CAIF packet.
*/
void *cfpkt_tonative(struct cfpkt *pkt);
/*
* Returns packet information for a packet.
* pkt Packet to get info from;
* @return Packet information
*/
struct caif_payload_info *cfpkt_info(struct cfpkt *pkt);
/** cfpkt_set_prio - set priority for a CAIF packet.
*
* @pkt: The CAIF packet to be adjusted.
* @prio: one of TC_PRIO_ constants.
*/
void cfpkt_set_prio(struct cfpkt *pkt, int prio);
#endif /* CFPKT_H_ */