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/*
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 * DMA helper functions
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 *
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 * Copyright (c) 2009 Red Hat
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 *
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 * This work is licensed under the terms of the GNU General Public License
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 * (GNU GPL), version 2 or later.
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 */
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#ifndef DMA_H
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#define DMA_H
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#include <stdio.h>
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#include "exec/memory.h"
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#include "exec/address-spaces.h"
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#include "hw/hw.h"
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#include "block/block.h"
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#include "sysemu/kvm.h"
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typedef struct ScatterGatherEntry ScatterGatherEntry;
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typedef enum {
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    DMA_DIRECTION_TO_DEVICE = 0,
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    DMA_DIRECTION_FROM_DEVICE = 1,
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} DMADirection;
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struct QEMUSGList {
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    ScatterGatherEntry *sg;
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    int nsg;
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    int nalloc;
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    size_t size;
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    DeviceState *dev;
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    AddressSpace *as;
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};
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#ifndef CONFIG_USER_ONLY
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/*
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 * When an IOMMU is present, bus addresses become distinct from
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 * CPU/memory physical addresses and may be a different size.  Because
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 * the IOVA size depends more on the bus than on the platform, we more
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 * or less have to treat these as 64-bit always to cover all (or at
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 * least most) cases.
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 */
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typedef uint64_t dma_addr_t;
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#define DMA_ADDR_BITS 64
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#define DMA_ADDR_FMT "%" PRIx64
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static inline void dma_barrier(AddressSpace *as, DMADirection dir)
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{
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    /*
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     * This is called before DMA read and write operations
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     * unless the _relaxed form is used and is responsible
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     * for providing some sane ordering of accesses vs
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     * concurrently running VCPUs.
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     *
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     * Users of map(), unmap() or lower level st/ld_*
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     * operations are responsible for providing their own
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     * ordering via barriers.
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     *
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     * This primitive implementation does a simple smp_mb()
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     * before each operation which provides pretty much full
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     * ordering.
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     *
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     * A smarter implementation can be devised if needed to
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     * use lighter barriers based on the direction of the
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     * transfer, the DMA context, etc...
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     */
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    if (kvm_enabled()) {
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        smp_mb();
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    }
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}
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/* Checks that the given range of addresses is valid for DMA.  This is
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 * useful for certain cases, but usually you should just use
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 * dma_memory_{read,write}() and check for errors */
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static inline bool dma_memory_valid(AddressSpace *as,
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                                    dma_addr_t addr, dma_addr_t len,
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                                    DMADirection dir)
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{
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    return address_space_access_valid(as, addr, len,
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                                      dir == DMA_DIRECTION_FROM_DEVICE);
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}
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static inline int dma_memory_rw_relaxed(AddressSpace *as, dma_addr_t addr,
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                                        void *buf, dma_addr_t len,
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                                        DMADirection dir)
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{
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    return address_space_rw(as, addr, buf, len, dir == DMA_DIRECTION_FROM_DEVICE);
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}
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static inline int dma_memory_read_relaxed(AddressSpace *as, dma_addr_t addr,
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                                          void *buf, dma_addr_t len)
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{
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    return dma_memory_rw_relaxed(as, addr, buf, len, DMA_DIRECTION_TO_DEVICE);
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}
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static inline int dma_memory_write_relaxed(AddressSpace *as, dma_addr_t addr,
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                                           const void *buf, dma_addr_t len)
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{
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    return dma_memory_rw_relaxed(as, addr, (void *)buf, len,
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                                 DMA_DIRECTION_FROM_DEVICE);
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}
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static inline int dma_memory_rw(AddressSpace *as, dma_addr_t addr,
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                                void *buf, dma_addr_t len,
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                                DMADirection dir)
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{
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    dma_barrier(as, dir);
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    return dma_memory_rw_relaxed(as, addr, buf, len, dir);
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}
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static inline int dma_memory_read(AddressSpace *as, dma_addr_t addr,
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                                  void *buf, dma_addr_t len)
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{
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    return dma_memory_rw(as, addr, buf, len, DMA_DIRECTION_TO_DEVICE);
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}
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static inline int dma_memory_write(AddressSpace *as, dma_addr_t addr,
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                                   const void *buf, dma_addr_t len)
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{
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    return dma_memory_rw(as, addr, (void *)buf, len,
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                         DMA_DIRECTION_FROM_DEVICE);
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}
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int dma_memory_set(AddressSpace *as, dma_addr_t addr, uint8_t c, dma_addr_t len);
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static inline void *dma_memory_map(AddressSpace *as,
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                                   dma_addr_t addr, dma_addr_t *len,
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                                   DMADirection dir)
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{
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    hwaddr xlen = *len;
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    void *p;
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    p = address_space_map(as, addr, &xlen, dir == DMA_DIRECTION_FROM_DEVICE);
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    *len = xlen;
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    return p;
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}
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static inline void dma_memory_unmap(AddressSpace *as,
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                                    void *buffer, dma_addr_t len,
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                                    DMADirection dir, dma_addr_t access_len)
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{
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    address_space_unmap(as, buffer, (hwaddr)len,
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                        dir == DMA_DIRECTION_FROM_DEVICE, access_len);
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}
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#define DEFINE_LDST_DMA(_lname, _sname, _bits, _end) \
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    static inline uint##_bits##_t ld##_lname##_##_end##_dma(AddressSpace *as, \
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                                                            dma_addr_t addr) \
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    {                                                                   \
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        uint##_bits##_t val;                                            \
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        dma_memory_read(as, addr, &val, (_bits) / 8);                   \
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        return _end##_bits##_to_cpu(val);                               \
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    }                                                                   \
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    static inline void st##_sname##_##_end##_dma(AddressSpace *as,      \
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                                                 dma_addr_t addr,       \
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                                                 uint##_bits##_t val)   \
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    {                                                                   \
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        val = cpu_to_##_end##_bits(val);                                \
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        dma_memory_write(as, addr, &val, (_bits) / 8);                  \
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    }
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static inline uint8_t ldub_dma(AddressSpace *as, dma_addr_t addr)
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{
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    uint8_t val;
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    dma_memory_read(as, addr, &val, 1);
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    return val;
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}
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static inline void stb_dma(AddressSpace *as, dma_addr_t addr, uint8_t val)
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{
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    dma_memory_write(as, addr, &val, 1);
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}
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DEFINE_LDST_DMA(uw, w, 16, le);
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DEFINE_LDST_DMA(l, l, 32, le);
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DEFINE_LDST_DMA(q, q, 64, le);
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DEFINE_LDST_DMA(uw, w, 16, be);
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DEFINE_LDST_DMA(l, l, 32, be);
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DEFINE_LDST_DMA(q, q, 64, be);
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#undef DEFINE_LDST_DMA
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struct ScatterGatherEntry {
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    dma_addr_t base;
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    dma_addr_t len;
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};
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void qemu_sglist_init(QEMUSGList *qsg, DeviceState *dev, int alloc_hint,
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                      AddressSpace *as);
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void qemu_sglist_add(QEMUSGList *qsg, dma_addr_t base, dma_addr_t len);
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void qemu_sglist_destroy(QEMUSGList *qsg);
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#endif
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typedef BlockDriverAIOCB *DMAIOFunc(BlockDriverState *bs, int64_t sector_num,
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                                 QEMUIOVector *iov, int nb_sectors,
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                                 BlockDriverCompletionFunc *cb, void *opaque);
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BlockDriverAIOCB *dma_bdrv_io(BlockDriverState *bs,
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                              QEMUSGList *sg, uint64_t sector_num,
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                              DMAIOFunc *io_func, BlockDriverCompletionFunc *cb,
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                              void *opaque, DMADirection dir);
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BlockDriverAIOCB *dma_bdrv_read(BlockDriverState *bs,
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                                QEMUSGList *sg, uint64_t sector,
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                                BlockDriverCompletionFunc *cb, void *opaque);
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BlockDriverAIOCB *dma_bdrv_write(BlockDriverState *bs,
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                                 QEMUSGList *sg, uint64_t sector,
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                                 BlockDriverCompletionFunc *cb, void *opaque);
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uint64_t dma_buf_read(uint8_t *ptr, int32_t len, QEMUSGList *sg);
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uint64_t dma_buf_write(uint8_t *ptr, int32_t len, QEMUSGList *sg);
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void dma_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie,
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                    QEMUSGList *sg, enum BlockAcctType type);
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#endif