Data transfer buffer. More...

#include <stdint.h>
#include <ipxe/iobuf.h>
#include <ipxe/uaccess.h>
#include <ipxe/interface.h>
#include <ipxe/xfer.h>

Data Structures
struct	xfer_buffer
	A data transfer buffer. More...

struct	xfer_buffer_operations
	Data transfer buffer operations. More...

Macros
#define	xfer_buffer_TYPE(object_type) typeof ( struct xfer_buffer * ( object_type ) )

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)

static void	xferbuf_malloc_init (struct xfer_buffer *xferbuf)
	Initialise malloc()-based data transfer buffer. More...

static void	xferbuf_umalloc_init (struct xfer_buffer xferbuf, userptr_t data)
	Initialise umalloc()-based data transfer buffer. More...

void	xferbuf_free (struct xfer_buffer *xferbuf)
	Free data transfer buffer. More...

int	xferbuf_write (struct xfer_buffer xferbuf, size_t offset, const void data, size_t len)
	Write to data transfer buffer. More...

int	xferbuf_read (struct xfer_buffer xferbuf, size_t offset, void data, size_t len)
	Read from data transfer buffer. More...

int	xferbuf_deliver (struct xfer_buffer xferbuf, struct io_buffer iobuf, struct xfer_metadata *meta)
	Add received data to data transfer buffer. More...

struct xfer_buffer *	xfer_buffer (struct interface *intf)
	Get underlying data transfer buffer. More...

Variables
struct xfer_buffer_operations	xferbuf_malloc_operations
	malloc()-based data buffer operations More...

struct xfer_buffer_operations	xferbuf_umalloc_operations
	umalloc()-based data buffer operations More...

Detailed Description

Data transfer buffer.

Definition in file xferbuf.h.

Macro Definition Documentation

◆ xfer_buffer_TYPE

#define xfer_buffer_TYPE ( object_type ) typeof ( struct xfer_buffer * ( object_type ) )

Definition at line 102 of file xferbuf.h.

Function Documentation

◆ FILE_LICENCE()

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )

◆ xferbuf_malloc_init()

static void xferbuf_malloc_init ( struct xfer_buffer * xferbuf )

inlinestatic

Initialise malloc()-based data transfer buffer.

Parameters

xferbuf Data transfer buffer

Definition at line 76 of file xferbuf.h.

                                                     {
         xferbuf->op = &xferbuf_malloc_operations;
 }

References xfer_buffer::op, and xferbuf_malloc_operations.

Referenced by create_validator(), and peerblk_open().

◆ xferbuf_umalloc_init()

static void xferbuf_umalloc_init	(	struct xfer_buffer *	xferbuf,
		userptr_t *	data
	)

inlinestatic

Initialise umalloc()-based data transfer buffer.

Parameters

xferbuf	Data transfer buffer
data	User pointer

Definition at line 87 of file xferbuf.h.

                                                                       {
         xferbuf->data = data;
         xferbuf->op = &xferbuf_umalloc_operations;
 }

References xfer_buffer::data, data, xfer_buffer::op, and xferbuf_umalloc_operations.

Referenced by create_downloader(), and peermux_filter().

◆ xferbuf_free()

void xferbuf_free ( struct xfer_buffer * xferbuf )

Free data transfer buffer.

Parameters

xferbuf Data transfer buffer

Definition at line 58 of file xferbuf.c.

                                                   {
 
         xferbuf->op->realloc ( xferbuf, 0 );
         xferbuf->len = 0;
         xferbuf->pos = 0;
 }

References xfer_buffer::len, xfer_buffer::op, xfer_buffer::pos, and xfer_buffer_operations::realloc.

Referenced by peerblk_reset(), peermux_free(), validator_free(), and validator_xfer_close().

◆ xferbuf_write()

int xferbuf_write	(	struct xfer_buffer *	xferbuf,
		size_t	offset,
		const void *	data,
		size_t	len
	)

Write to data transfer buffer.

Parameters

xferbuf	Data transfer buffer
offset	Starting offset
data	Data to write
len	Length of data

Definition at line 98 of file xferbuf.c.

                                                    {
         size_t max_len;
         int rc;
 
         /* Check for overflow */
         max_len = ( offset + len );
         if ( max_len < offset )
                 return -EOVERFLOW;
 
         /* Ensure buffer is large enough to contain this write */
         if ( ( rc = xferbuf_ensure_size ( xferbuf, max_len ) ) != 0 )
                 return rc;
 
         /* Copy data to buffer */
         profile_start ( &xferbuf_write_profiler );
         xferbuf->op->write ( xferbuf, offset, data, len );
         profile_stop ( &xferbuf_write_profiler );
 
         return 0;
 }

References data, EOVERFLOW, len, max_len, offset, xfer_buffer::op, profile_start(), profile_stop(), rc, xfer_buffer_operations::write, and xferbuf_ensure_size().

Referenced by peerblk_decrypt_write(), peerblk_retrieval_rx(), and xferbuf_deliver().

◆ xferbuf_read()

int xferbuf_read	(	struct xfer_buffer *	xferbuf,
		size_t	offset,
		void *	data,
		size_t	len
	)

Read from data transfer buffer.

Parameters

xferbuf	Data transfer buffer
offset	Starting offset
data	Data to write
len	Length of data

Definition at line 128 of file xferbuf.c.

                                             {
 
         /* Check that read is within buffer range */
         if ( ( offset > xferbuf->len ) ||
              ( len > ( xferbuf->len - offset ) ) )
                 return -ENOENT;
 
         /* Copy data from buffer */
         profile_start ( &xferbuf_read_profiler );
         xferbuf->op->read ( xferbuf, offset, data, len );
         profile_stop ( &xferbuf_read_profiler );
 
         return 0;
 }

References data, ENOENT, len, xfer_buffer::len, offset, xfer_buffer::op, profile_start(), profile_stop(), and xfer_buffer_operations::read.

Referenced by peerblk_decrypt_read().

◆ xferbuf_deliver()

int xferbuf_deliver	(	struct xfer_buffer *	xferbuf,
		struct io_buffer *	iobuf,
		struct xfer_metadata *	meta
	)

Add received data to data transfer buffer.

Parameters

xferbuf	Data transfer buffer
iobuf	I/O buffer
meta	Data transfer metadata

Return values

rc	Return status code

Definition at line 152 of file xferbuf.c.

                                                    {
         size_t len = iob_len ( iobuf );
         size_t pos;
         int rc;
 
         /* Start profiling */
         profile_start ( &xferbuf_deliver_profiler );
 
         /* Calculate new buffer position */
         pos = xferbuf->pos;
         if ( meta->flags & XFER_FL_ABS_OFFSET )
                 pos = 0;
         pos += meta->offset;
 
         /* Write data to buffer */
         if ( ( rc = xferbuf_write ( xferbuf, pos, iobuf->data, len ) ) != 0 )
                 goto done;
 
         /* Update current buffer position */
         xferbuf->pos = ( pos + len );
 
  done:
         free_iob ( iobuf );
         profile_stop ( &xferbuf_deliver_profiler );
         return rc;
 }

References io_buffer::data, done, free_iob(), iob_len(), len, meta(), xfer_buffer::pos, profile_start(), profile_stop(), rc, XFER_FL_ABS_OFFSET, and xferbuf_write().

Referenced by blktrans_deliver(), downloader_deliver(), efi_pxe_tftp_deliver(), peermux_info_deliver(), and validator_xfer_deliver().

◆ xfer_buffer()

struct xfer_buffer* xfer_buffer ( struct interface * intf )

Get underlying data transfer buffer.

Parameters

interface Data transfer interface

Return values

xferbuf Data transfer buffer, or NULL on error

This call will check that the xfer_buffer() handler belongs to the destination interface which also provides xfer_deliver() for this interface.

This is done to prevent accidental accesses to a data transfer buffer which may be located behind a non-transparent datapath via a series of pass-through interfaces.

Definition at line 301 of file xferbuf.c.

                                                             {
         struct interface *dest;
         xfer_buffer_TYPE ( void * ) *op =
                 intf_get_dest_op ( intf, xfer_buffer, &dest );
         void *object = intf_object ( dest );
         struct interface *xfer_deliver_dest;
         struct xfer_buffer *xferbuf;
 
         /* Check that this operation is provided by the same interface
          * which handles xfer_deliver().
          */
         ( void ) intf_get_dest_op ( intf, xfer_deliver, &xfer_deliver_dest );
 
         if ( op && ( dest == xfer_deliver_dest ) ) {
                 xferbuf = op ( object );
         } else {
                 /* Default is to not have a data transfer buffer */
                 xferbuf = NULL;
         }
 
         intf_put ( xfer_deliver_dest );
         intf_put ( dest );
         return xferbuf;
 }