qemu/dma.h
aliguori 59a703ebaa Introduce block dma helpers (Avi Kivity)
These helpers perform read/write requests on entire scatter/gather lists,
relieving the device emulation code from mapping and unmapping physical
memory, and from looping when map resources are exhausted.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6524 c046a42c-6fe2-441c-8c8c-71466251a162
2009-02-05 21:23:58 +00:00

42 lines
1.1 KiB
C

/*
* DMA helper functions
*
* Copyright (c) 2009 Red Hat
*
* This work is licensed under the terms of the GNU General Public License
* (GNU GPL), version 2 or later.
*/
#ifndef DMA_H
#define DMA_H
#include <stdio.h>
#include "cpu.h"
#include "block.h"
typedef struct {
target_phys_addr_t base;
target_phys_addr_t len;
} ScatterGatherEntry;
typedef struct {
ScatterGatherEntry *sg;
int nsg;
int nalloc;
target_phys_addr_t size;
} QEMUSGList;
void qemu_sglist_init(QEMUSGList *qsg, int alloc_hint);
void qemu_sglist_add(QEMUSGList *qsg, target_phys_addr_t base,
target_phys_addr_t len);
void qemu_sglist_destroy(QEMUSGList *qsg);
BlockDriverAIOCB *dma_bdrv_read(BlockDriverState *bs,
QEMUSGList *sg, uint64_t sector,
BlockDriverCompletionFunc *cb, void *opaque);
BlockDriverAIOCB *dma_bdrv_write(BlockDriverState *bs,
QEMUSGList *sg, uint64_t sector,
BlockDriverCompletionFunc *cb, void *opaque);
#endif