#ifndef _GPXE_XFER_H
#define _GPXE_XFER_H
/** @file
*
* Data transfer interfaces
*
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <stddef.h>
#include <stdarg.h>
#include <gpxe/interface.h>
#include <gpxe/iobuf.h>
struct xfer_interface;
struct xfer_metadata;
/** Data transfer interface operations */
struct xfer_interface_operations {
/** Close interface
*
* @v xfer Data transfer interface
* @v rc Reason for close
*/
void ( * close ) ( struct xfer_interface *xfer, int rc );
/** Redirect to new location
*
* @v xfer Data transfer interface
* @v type New location type
* @v args Remaining arguments depend upon location type
* @ret rc Return status code
*/
int ( * vredirect ) ( struct xfer_interface *xfer, int type,
va_list args );
/** Check flow control window
*
* @v xfer Data transfer interface
* @ret len Length of window
*
* Flow control is regarded as advisory but not mandatory.
* Users who have control over their own rate of data
* generation should perform a flow control check before
* generating new data. Users who have no control (such as
* NIC drivers or filter layers) are not obliged to check.
*
* Data transfer interfaces must be prepared to accept
* datagrams even if they are advertising a window of zero
* bytes.
*/
size_t ( * window ) ( struct xfer_interface *xfer );
/** Allocate I/O buffer
*
* @v xfer Data transfer interface
* @v len I/O buffer payload length
* @ret iobuf I/O buffer
*/
struct io_buffer * ( * alloc_iob ) ( struct xfer_interface *xfer,
size_t len );
/** Deliver datagram as I/O buffer with metadata
*
* @v xfer Data transfer interface
* @v iobuf Datagram I/O buffer
* @v meta Data transfer metadata
* @ret rc Return status code
*
* A data transfer interface that wishes to support only raw
* data delivery should set this method to
* xfer_deliver_as_raw().
*/
int ( * deliver_iob ) ( struct xfer_interface *xfer,
struct io_buffer *iobuf,
struct xfer_metadata *meta );
/** Deliver datagram as raw data
*
* @v xfer Data transfer interface
* @v data Data buffer
* @v len Length of data buffer
* @ret rc Return status code
*
* A data transfer interface that wishes to support only I/O
* buffer delivery should set this method to
* xfer_deliver_as_iob().
*/
int ( * deliver_raw ) ( struct xfer_interface *xfer,
const void *data, size_t len );
};
/** A data transfer interface */
struct xfer_interface {
/** Generic object communication interface */
struct interface intf;
/** Operations for received messages */
struct xfer_interface_operations *op;
};
/** Basis positions for seek() events */
enum seek_whence {
SEEK_CUR = 0,
SEEK_SET,
};
/** Data transfer metadata */
struct xfer_metadata {
/** Position of data within stream */
off_t offset;
/** Basis for data position
*
* Must be one of @c SEEK_CUR or @c SEEK_SET.
*/
int whence;
/** Source socket address, or NULL */
struct sockaddr *src;
/** Destination socket address, or NULL */
struct sockaddr *dest;
/** Network device, or NULL */
struct net_device *netdev;
};
/**
* Describe seek basis
*
* @v whence Basis for new position
*/
static inline __attribute__ (( always_inline )) const char *
whence_text ( int whence ) {
switch ( whence ) {
case SEEK_CUR: return "CUR";
case SEEK_SET: return "SET";
default: return "INVALID";
}
}
extern struct xfer_interface null_xfer;
extern struct xfer_interface_operations null_xfer_ops;
extern void xfer_close ( struct xfer_interface *xfer, int rc );
extern int xfer_vredirect ( struct xfer_interface *xfer, int type,
va_list args );
extern int xfer_redirect ( struct xfer_interface *xfer, int type, ... );
extern size_t xfer_window ( struct xfer_interface *xfer );
extern struct io_buffer * xfer_alloc_iob ( struct xfer_interface *xfer,
size_t len );
extern int xfer_deliver_iob ( struct xfer_interface *xfer,
struct io_buffer *iobuf );
extern int xfer_deliver_iob_meta ( struct xfer_interface *xfer,
struct io_buffer *iobuf,
struct xfer_metadata *meta );
extern int xfer_deliver_raw ( struct xfer_interface *xfer,
const void *data, size_t len );
extern int xfer_vprintf ( struct xfer_interface *xfer,
const char *format, va_list args );
extern int __attribute__ (( format ( printf, 2, 3 ) ))
xfer_printf ( struct xfer_interface *xfer, const char *format, ... );
extern int xfer_seek ( struct xfer_interface *xfer, off_t offset, int whence );
extern void ignore_xfer_close ( struct xfer_interface *xfer, int rc );
extern int ignore_xfer_vredirect ( struct xfer_interface *xfer,
int type, va_list args );
extern size_t unlimited_xfer_window ( struct xfer_interface *xfer );
extern size_t no_xfer_window ( struct xfer_interface *xfer );
extern struct io_buffer * default_xfer_alloc_iob ( struct xfer_interface *xfer,
size_t len );
extern int xfer_deliver_as_raw ( struct xfer_interface *xfer,
struct io_buffer *iobuf,
struct xfer_metadata *meta );
extern int xfer_deliver_as_iob ( struct xfer_interface *xfer,
const void *data, size_t len );
extern int ignore_xfer_deliver_raw ( struct xfer_interface *xfer,
const void *data __unused, size_t len );
/**
* Initialise a data transfer interface
*
* @v xfer Data transfer interface
* @v op Data transfer interface operations
* @v refcnt Containing object reference counter, or NULL
*/
static inline void xfer_init ( struct xfer_interface *xfer,
struct xfer_interface_operations *op,
struct refcnt *refcnt ) {
xfer->intf.dest = &null_xfer.intf;
xfer->intf.refcnt = refcnt;
xfer->op = op;
}
/**
* Initialise a static data transfer interface
*
* @v operations Data transfer interface operations
*/
#define XFER_INIT( operations ) { \
.intf = { \
.dest = &null_xfer.intf, \
.refcnt = NULL, \
}, \
.op = operations, \
}
/**
* Get data transfer interface from generic object communication interface
*
* @v intf Generic object communication interface
* @ret xfer Data transfer interface
*/
static inline __attribute__ (( always_inline )) struct xfer_interface *
intf_to_xfer ( struct interface *intf ) {
return container_of ( intf, struct xfer_interface, intf );
}
/**
* Get reference to destination data transfer interface
*
* @v xfer Data transfer interface
* @ret dest Destination interface
*/
static inline __attribute__ (( always_inline )) struct xfer_interface *
xfer_get_dest ( struct xfer_interface *xfer ) {
return intf_to_xfer ( intf_get ( xfer->intf.dest ) );
}
/**
* Drop reference to data transfer interface
*
* @v xfer Data transfer interface
*/
static inline __attribute__ (( always_inline )) void
xfer_put ( struct xfer_interface *xfer ) {
intf_put ( &xfer->intf );
}
/**
* Plug a data transfer interface into a new destination interface
*
* @v xfer Data transfer interface
* @v dest New destination interface
*/
static inline __attribute__ (( always_inline )) void
xfer_plug ( struct xfer_interface *xfer, struct xfer_interface *dest ) {
plug ( &xfer->intf, &dest->intf );
}
/**
* Plug two data transfer interfaces together
*
* @v a Data transfer interface A
* @v b Data transfer interface B
*/
static inline __attribute__ (( always_inline )) void
xfer_plug_plug ( struct xfer_interface *a, struct xfer_interface *b ) {
plug_plug ( &a->intf, &b->intf );
}
/**
* Unplug a data transfer interface
*
* @v xfer Data transfer interface
*/
static inline __attribute__ (( always_inline )) void
xfer_unplug ( struct xfer_interface *xfer ) {
plug ( &xfer->intf, &null_xfer.intf );
}
/**
* Stop using a data transfer interface
*
* @v xfer Data transfer interface
*
* After calling this method, no further messages will be received via
* the interface.
*/
static inline void xfer_nullify ( struct xfer_interface *xfer ) {
xfer->op = &null_xfer_ops;
};
#endif /* _GPXE_XFER_H */
