+++ /dev/null
-/*
- * 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.
- */
-
-#include "qemu/osdep.h"
-#include "sysemu/block-backend.h"
-#include "sysemu/dma.h"
-#include "trace/trace-root.h"
-#include "qemu/thread.h"
-#include "qemu/main-loop.h"
-#include "sysemu/cpu-timers.h"
-#include "qemu/range.h"
-
-/* #define DEBUG_IOMMU */
-
-int dma_memory_set(AddressSpace *as, dma_addr_t addr, uint8_t c, dma_addr_t len)
-{
- dma_barrier(as, DMA_DIRECTION_FROM_DEVICE);
-
-#define FILLBUF_SIZE 512
- uint8_t fillbuf[FILLBUF_SIZE];
- int l;
- bool error = false;
-
- memset(fillbuf, c, FILLBUF_SIZE);
- while (len > 0) {
- l = len < FILLBUF_SIZE ? len : FILLBUF_SIZE;
- error |= address_space_write(as, addr, MEMTXATTRS_UNSPECIFIED,
- fillbuf, l);
- len -= l;
- addr += l;
- }
-
- return error;
-}
-
-void qemu_sglist_init(QEMUSGList *qsg, DeviceState *dev, int alloc_hint,
- AddressSpace *as)
-{
- qsg->sg = g_malloc(alloc_hint * sizeof(ScatterGatherEntry));
- qsg->nsg = 0;
- qsg->nalloc = alloc_hint;
- qsg->size = 0;
- qsg->as = as;
- qsg->dev = dev;
- object_ref(OBJECT(dev));
-}
-
-void qemu_sglist_add(QEMUSGList *qsg, dma_addr_t base, dma_addr_t len)
-{
- if (qsg->nsg == qsg->nalloc) {
- qsg->nalloc = 2 * qsg->nalloc + 1;
- qsg->sg = g_realloc(qsg->sg, qsg->nalloc * sizeof(ScatterGatherEntry));
- }
- qsg->sg[qsg->nsg].base = base;
- qsg->sg[qsg->nsg].len = len;
- qsg->size += len;
- ++qsg->nsg;
-}
-
-void qemu_sglist_destroy(QEMUSGList *qsg)
-{
- object_unref(OBJECT(qsg->dev));
- g_free(qsg->sg);
- memset(qsg, 0, sizeof(*qsg));
-}
-
-typedef struct {
- BlockAIOCB common;
- AioContext *ctx;
- BlockAIOCB *acb;
- QEMUSGList *sg;
- uint32_t align;
- uint64_t offset;
- DMADirection dir;
- int sg_cur_index;
- dma_addr_t sg_cur_byte;
- QEMUIOVector iov;
- QEMUBH *bh;
- DMAIOFunc *io_func;
- void *io_func_opaque;
-} DMAAIOCB;
-
-static void dma_blk_cb(void *opaque, int ret);
-
-static void reschedule_dma(void *opaque)
-{
- DMAAIOCB *dbs = (DMAAIOCB *)opaque;
-
- assert(!dbs->acb && dbs->bh);
- qemu_bh_delete(dbs->bh);
- dbs->bh = NULL;
- dma_blk_cb(dbs, 0);
-}
-
-static void dma_blk_unmap(DMAAIOCB *dbs)
-{
- int i;
-
- for (i = 0; i < dbs->iov.niov; ++i) {
- dma_memory_unmap(dbs->sg->as, dbs->iov.iov[i].iov_base,
- dbs->iov.iov[i].iov_len, dbs->dir,
- dbs->iov.iov[i].iov_len);
- }
- qemu_iovec_reset(&dbs->iov);
-}
-
-static void dma_complete(DMAAIOCB *dbs, int ret)
-{
- trace_dma_complete(dbs, ret, dbs->common.cb);
-
- assert(!dbs->acb && !dbs->bh);
- dma_blk_unmap(dbs);
- if (dbs->common.cb) {
- dbs->common.cb(dbs->common.opaque, ret);
- }
- qemu_iovec_destroy(&dbs->iov);
- qemu_aio_unref(dbs);
-}
-
-static void dma_blk_cb(void *opaque, int ret)
-{
- DMAAIOCB *dbs = (DMAAIOCB *)opaque;
- dma_addr_t cur_addr, cur_len;
- void *mem;
-
- trace_dma_blk_cb(dbs, ret);
-
- dbs->acb = NULL;
- dbs->offset += dbs->iov.size;
-
- if (dbs->sg_cur_index == dbs->sg->nsg || ret < 0) {
- dma_complete(dbs, ret);
- return;
- }
- dma_blk_unmap(dbs);
-
- while (dbs->sg_cur_index < dbs->sg->nsg) {
- cur_addr = dbs->sg->sg[dbs->sg_cur_index].base + dbs->sg_cur_byte;
- cur_len = dbs->sg->sg[dbs->sg_cur_index].len - dbs->sg_cur_byte;
- mem = dma_memory_map(dbs->sg->as, cur_addr, &cur_len, dbs->dir);
- /*
- * Make reads deterministic in icount mode. Windows sometimes issues
- * disk read requests with overlapping SGs. It leads
- * to non-determinism, because resulting buffer contents may be mixed
- * from several sectors. This code splits all SGs into several
- * groups. SGs in every group do not overlap.
- */
- if (mem && icount_enabled() && dbs->dir == DMA_DIRECTION_FROM_DEVICE) {
- int i;
- for (i = 0 ; i < dbs->iov.niov ; ++i) {
- if (ranges_overlap((intptr_t)dbs->iov.iov[i].iov_base,
- dbs->iov.iov[i].iov_len, (intptr_t)mem,
- cur_len)) {
- dma_memory_unmap(dbs->sg->as, mem, cur_len,
- dbs->dir, cur_len);
- mem = NULL;
- break;
- }
- }
- }
- if (!mem)
- break;
- qemu_iovec_add(&dbs->iov, mem, cur_len);
- dbs->sg_cur_byte += cur_len;
- if (dbs->sg_cur_byte == dbs->sg->sg[dbs->sg_cur_index].len) {
- dbs->sg_cur_byte = 0;
- ++dbs->sg_cur_index;
- }
- }
-
- if (dbs->iov.size == 0) {
- trace_dma_map_wait(dbs);
- dbs->bh = aio_bh_new(dbs->ctx, reschedule_dma, dbs);
- cpu_register_map_client(dbs->bh);
- return;
- }
-
- if (!QEMU_IS_ALIGNED(dbs->iov.size, dbs->align)) {
- qemu_iovec_discard_back(&dbs->iov,
- QEMU_ALIGN_DOWN(dbs->iov.size, dbs->align));
- }
-
- aio_context_acquire(dbs->ctx);
- dbs->acb = dbs->io_func(dbs->offset, &dbs->iov,
- dma_blk_cb, dbs, dbs->io_func_opaque);
- aio_context_release(dbs->ctx);
- assert(dbs->acb);
-}
-
-static void dma_aio_cancel(BlockAIOCB *acb)
-{
- DMAAIOCB *dbs = container_of(acb, DMAAIOCB, common);
-
- trace_dma_aio_cancel(dbs);
-
- assert(!(dbs->acb && dbs->bh));
- if (dbs->acb) {
- /* This will invoke dma_blk_cb. */
- blk_aio_cancel_async(dbs->acb);
- return;
- }
-
- if (dbs->bh) {
- cpu_unregister_map_client(dbs->bh);
- qemu_bh_delete(dbs->bh);
- dbs->bh = NULL;
- }
- if (dbs->common.cb) {
- dbs->common.cb(dbs->common.opaque, -ECANCELED);
- }
-}
-
-static AioContext *dma_get_aio_context(BlockAIOCB *acb)
-{
- DMAAIOCB *dbs = container_of(acb, DMAAIOCB, common);
-
- return dbs->ctx;
-}
-
-static const AIOCBInfo dma_aiocb_info = {
- .aiocb_size = sizeof(DMAAIOCB),
- .cancel_async = dma_aio_cancel,
- .get_aio_context = dma_get_aio_context,
-};
-
-BlockAIOCB *dma_blk_io(AioContext *ctx,
- QEMUSGList *sg, uint64_t offset, uint32_t align,
- DMAIOFunc *io_func, void *io_func_opaque,
- BlockCompletionFunc *cb,
- void *opaque, DMADirection dir)
-{
- DMAAIOCB *dbs = qemu_aio_get(&dma_aiocb_info, NULL, cb, opaque);
-
- trace_dma_blk_io(dbs, io_func_opaque, offset, (dir == DMA_DIRECTION_TO_DEVICE));
-
- dbs->acb = NULL;
- dbs->sg = sg;
- dbs->ctx = ctx;
- dbs->offset = offset;
- dbs->align = align;
- dbs->sg_cur_index = 0;
- dbs->sg_cur_byte = 0;
- dbs->dir = dir;
- dbs->io_func = io_func;
- dbs->io_func_opaque = io_func_opaque;
- dbs->bh = NULL;
- qemu_iovec_init(&dbs->iov, sg->nsg);
- dma_blk_cb(dbs, 0);
- return &dbs->common;
-}
-
-
-static
-BlockAIOCB *dma_blk_read_io_func(int64_t offset, QEMUIOVector *iov,
- BlockCompletionFunc *cb, void *cb_opaque,
- void *opaque)
-{
- BlockBackend *blk = opaque;
- return blk_aio_preadv(blk, offset, iov, 0, cb, cb_opaque);
-}
-
-BlockAIOCB *dma_blk_read(BlockBackend *blk,
- QEMUSGList *sg, uint64_t offset, uint32_t align,
- void (*cb)(void *opaque, int ret), void *opaque)
-{
- return dma_blk_io(blk_get_aio_context(blk), sg, offset, align,
- dma_blk_read_io_func, blk, cb, opaque,
- DMA_DIRECTION_FROM_DEVICE);
-}
-
-static
-BlockAIOCB *dma_blk_write_io_func(int64_t offset, QEMUIOVector *iov,
- BlockCompletionFunc *cb, void *cb_opaque,
- void *opaque)
-{
- BlockBackend *blk = opaque;
- return blk_aio_pwritev(blk, offset, iov, 0, cb, cb_opaque);
-}
-
-BlockAIOCB *dma_blk_write(BlockBackend *blk,
- QEMUSGList *sg, uint64_t offset, uint32_t align,
- void (*cb)(void *opaque, int ret), void *opaque)
-{
- return dma_blk_io(blk_get_aio_context(blk), sg, offset, align,
- dma_blk_write_io_func, blk, cb, opaque,
- DMA_DIRECTION_TO_DEVICE);
-}
-
-
-static uint64_t dma_buf_rw(uint8_t *ptr, int32_t len, QEMUSGList *sg,
- DMADirection dir)
-{
- uint64_t resid;
- int sg_cur_index;
-
- resid = sg->size;
- sg_cur_index = 0;
- len = MIN(len, resid);
- while (len > 0) {
- ScatterGatherEntry entry = sg->sg[sg_cur_index++];
- int32_t xfer = MIN(len, entry.len);
- dma_memory_rw(sg->as, entry.base, ptr, xfer, dir);
- ptr += xfer;
- len -= xfer;
- resid -= xfer;
- }
-
- return resid;
-}
-
-uint64_t dma_buf_read(uint8_t *ptr, int32_t len, QEMUSGList *sg)
-{
- return dma_buf_rw(ptr, len, sg, DMA_DIRECTION_FROM_DEVICE);
-}
-
-uint64_t dma_buf_write(uint8_t *ptr, int32_t len, QEMUSGList *sg)
-{
- return dma_buf_rw(ptr, len, sg, DMA_DIRECTION_TO_DEVICE);
-}
-
-void dma_acct_start(BlockBackend *blk, BlockAcctCookie *cookie,
- QEMUSGList *sg, enum BlockAcctType type)
-{
- block_acct_start(blk_get_stats(blk), cookie, sg->size, type);
-}
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