qemu-patch-raspberry4/dma.h
David Gibson c65bcef306 iommu: Make sglists and dma_bdrv helpers use new universal DMA helpers
dma-helpers.c contains a number of helper functions for doing
scatter/gather DMA, and various block device related DMA.  Currently,
these directly access guest memory using cpu_physical_memory_*(),
assuming no IOMMU translation.

This patch updates this code to use the new universal DMA helper
functions.  qemu_sglist_init() now takes a DMAContext * to describe
the DMA address space in which the scatter/gather will take place.

We minimally update the callers qemu_sglist_init() to pass NULL
(i.e. no translation, same as current behaviour).  Some of those
callers should pass something else in some cases to allow proper IOMMU
translation in future, but that will be fixed in later patches.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-06-27 16:33:25 -05:00

164 lines
5.6 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 "hw/hw.h"
#include "block.h"
typedef struct DMAContext DMAContext;
typedef struct ScatterGatherEntry ScatterGatherEntry;
typedef enum {
DMA_DIRECTION_TO_DEVICE = 0,
DMA_DIRECTION_FROM_DEVICE = 1,
} DMADirection;
struct QEMUSGList {
ScatterGatherEntry *sg;
int nsg;
int nalloc;
size_t size;
DMAContext *dma;
};
#if defined(TARGET_PHYS_ADDR_BITS)
typedef target_phys_addr_t dma_addr_t;
#define DMA_ADDR_BITS TARGET_PHYS_ADDR_BITS
#define DMA_ADDR_FMT TARGET_FMT_plx
/* Checks that the given range of addresses is valid for DMA. This is
* useful for certain cases, but usually you should just use
* dma_memory_{read,write}() and check for errors */
static inline bool dma_memory_valid(DMAContext *dma, dma_addr_t addr,
dma_addr_t len, DMADirection dir)
{
/* Stub version, with no iommu we assume all bus addresses are valid */
return true;
}
static inline int dma_memory_rw(DMAContext *dma, dma_addr_t addr,
void *buf, dma_addr_t len, DMADirection dir)
{
/* Stub version when we have no iommu support */
cpu_physical_memory_rw(addr, buf, (target_phys_addr_t)len,
dir == DMA_DIRECTION_FROM_DEVICE);
return 0;
}
static inline int dma_memory_read(DMAContext *dma, dma_addr_t addr,
void *buf, dma_addr_t len)
{
return dma_memory_rw(dma, addr, buf, len, DMA_DIRECTION_TO_DEVICE);
}
static inline int dma_memory_write(DMAContext *dma, dma_addr_t addr,
const void *buf, dma_addr_t len)
{
return dma_memory_rw(dma, addr, (void *)buf, len,
DMA_DIRECTION_FROM_DEVICE);
}
int dma_memory_set(DMAContext *dma, dma_addr_t addr, uint8_t c, dma_addr_t len);
static inline void *dma_memory_map(DMAContext *dma,
dma_addr_t addr, dma_addr_t *len,
DMADirection dir)
{
target_phys_addr_t xlen = *len;
void *p;
p = cpu_physical_memory_map(addr, &xlen,
dir == DMA_DIRECTION_FROM_DEVICE);
*len = xlen;
return p;
}
static inline void dma_memory_unmap(DMAContext *dma,
void *buffer, dma_addr_t len,
DMADirection dir, dma_addr_t access_len)
{
return cpu_physical_memory_unmap(buffer, (target_phys_addr_t)len,
dir == DMA_DIRECTION_FROM_DEVICE,
access_len);
}
#define DEFINE_LDST_DMA(_lname, _sname, _bits, _end) \
static inline uint##_bits##_t ld##_lname##_##_end##_dma(DMAContext *dma, \
dma_addr_t addr) \
{ \
uint##_bits##_t val; \
dma_memory_read(dma, addr, &val, (_bits) / 8); \
return _end##_bits##_to_cpu(val); \
} \
static inline void st##_sname##_##_end##_dma(DMAContext *dma, \
dma_addr_t addr, \
uint##_bits##_t val) \
{ \
val = cpu_to_##_end##_bits(val); \
dma_memory_write(dma, addr, &val, (_bits) / 8); \
}
static inline uint8_t ldub_dma(DMAContext *dma, dma_addr_t addr)
{
uint8_t val;
dma_memory_read(dma, addr, &val, 1);
return val;
}
static inline void stb_dma(DMAContext *dma, dma_addr_t addr, uint8_t val)
{
dma_memory_write(dma, addr, &val, 1);
}
DEFINE_LDST_DMA(uw, w, 16, le);
DEFINE_LDST_DMA(l, l, 32, le);
DEFINE_LDST_DMA(q, q, 64, le);
DEFINE_LDST_DMA(uw, w, 16, be);
DEFINE_LDST_DMA(l, l, 32, be);
DEFINE_LDST_DMA(q, q, 64, be);
#undef DEFINE_LDST_DMA
struct ScatterGatherEntry {
dma_addr_t base;
dma_addr_t len;
};
void qemu_sglist_init(QEMUSGList *qsg, int alloc_hint, DMAContext *dma);
void qemu_sglist_add(QEMUSGList *qsg, dma_addr_t base, dma_addr_t len);
void qemu_sglist_destroy(QEMUSGList *qsg);
#endif
typedef BlockDriverAIOCB *DMAIOFunc(BlockDriverState *bs, int64_t sector_num,
QEMUIOVector *iov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
BlockDriverAIOCB *dma_bdrv_io(BlockDriverState *bs,
QEMUSGList *sg, uint64_t sector_num,
DMAIOFunc *io_func, BlockDriverCompletionFunc *cb,
void *opaque, DMADirection dir);
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);
uint64_t dma_buf_read(uint8_t *ptr, int32_t len, QEMUSGList *sg);
uint64_t dma_buf_write(uint8_t *ptr, int32_t len, QEMUSGList *sg);
void dma_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie,
QEMUSGList *sg, enum BlockAcctType type);
#endif