+++ /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 "dma.h"
-#include "trace.h"
-#include "qemu/range.h"
-#include "qemu/thread.h"
-
-/* #define DEBUG_IOMMU */
-
-static void do_dma_memory_set(AddressSpace *as,
- dma_addr_t addr, uint8_t c, dma_addr_t len)
-{
-#define FILLBUF_SIZE 512
- uint8_t fillbuf[FILLBUF_SIZE];
- int l;
-
- memset(fillbuf, c, FILLBUF_SIZE);
- while (len > 0) {
- l = len < FILLBUF_SIZE ? len : FILLBUF_SIZE;
- address_space_rw(as, addr, fillbuf, l, true);
- len -= l;
- addr += l;
- }
-}
-
-int dma_memory_set(DMAContext *dma, dma_addr_t addr, uint8_t c, dma_addr_t len)
-{
- dma_barrier(dma, DMA_DIRECTION_FROM_DEVICE);
-
- if (dma_has_iommu(dma)) {
- return iommu_dma_memory_set(dma, addr, c, len);
- }
- do_dma_memory_set(dma->as, addr, c, len);
-
- return 0;
-}
-
-void qemu_sglist_init(QEMUSGList *qsg, int alloc_hint, DMAContext *dma)
-{
- qsg->sg = g_malloc(alloc_hint * sizeof(ScatterGatherEntry));
- qsg->nsg = 0;
- qsg->nalloc = alloc_hint;
- qsg->size = 0;
- qsg->dma = dma;
-}
-
-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)
-{
- g_free(qsg->sg);
- memset(qsg, 0, sizeof(*qsg));
-}
-
-typedef struct {
- BlockDriverAIOCB common;
- BlockDriverState *bs;
- BlockDriverAIOCB *acb;
- QEMUSGList *sg;
- uint64_t sector_num;
- DMADirection dir;
- bool in_cancel;
- int sg_cur_index;
- dma_addr_t sg_cur_byte;
- QEMUIOVector iov;
- QEMUBH *bh;
- DMAIOFunc *io_func;
-} DMAAIOCB;
-
-static void dma_bdrv_cb(void *opaque, int ret);
-
-static void reschedule_dma(void *opaque)
-{
- DMAAIOCB *dbs = (DMAAIOCB *)opaque;
-
- qemu_bh_delete(dbs->bh);
- dbs->bh = NULL;
- dma_bdrv_cb(dbs, 0);
-}
-
-static void continue_after_map_failure(void *opaque)
-{
- DMAAIOCB *dbs = (DMAAIOCB *)opaque;
-
- dbs->bh = qemu_bh_new(reschedule_dma, dbs);
- qemu_bh_schedule(dbs->bh);
-}
-
-static void dma_bdrv_unmap(DMAAIOCB *dbs)
-{
- int i;
-
- for (i = 0; i < dbs->iov.niov; ++i) {
- dma_memory_unmap(dbs->sg->dma, 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);
-
- dma_bdrv_unmap(dbs);
- if (dbs->common.cb) {
- dbs->common.cb(dbs->common.opaque, ret);
- }
- qemu_iovec_destroy(&dbs->iov);
- if (dbs->bh) {
- qemu_bh_delete(dbs->bh);
- dbs->bh = NULL;
- }
- if (!dbs->in_cancel) {
- /* Requests may complete while dma_aio_cancel is in progress. In
- * this case, the AIOCB should not be released because it is still
- * referenced by dma_aio_cancel. */
- qemu_aio_release(dbs);
- }
-}
-
-static void dma_bdrv_cb(void *opaque, int ret)
-{
- DMAAIOCB *dbs = (DMAAIOCB *)opaque;
- dma_addr_t cur_addr, cur_len;
- void *mem;
-
- trace_dma_bdrv_cb(dbs, ret);
-
- dbs->acb = NULL;
- dbs->sector_num += dbs->iov.size / 512;
- dma_bdrv_unmap(dbs);
-
- if (dbs->sg_cur_index == dbs->sg->nsg || ret < 0) {
- dma_complete(dbs, ret);
- return;
- }
-
- 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->dma, cur_addr, &cur_len, dbs->dir);
- 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);
- cpu_register_map_client(dbs, continue_after_map_failure);
- return;
- }
-
- dbs->acb = dbs->io_func(dbs->bs, dbs->sector_num, &dbs->iov,
- dbs->iov.size / 512, dma_bdrv_cb, dbs);
- assert(dbs->acb);
-}
-
-static void dma_aio_cancel(BlockDriverAIOCB *acb)
-{
- DMAAIOCB *dbs = container_of(acb, DMAAIOCB, common);
-
- trace_dma_aio_cancel(dbs);
-
- if (dbs->acb) {
- BlockDriverAIOCB *acb = dbs->acb;
- dbs->acb = NULL;
- dbs->in_cancel = true;
- bdrv_aio_cancel(acb);
- dbs->in_cancel = false;
- }
- dbs->common.cb = NULL;
- dma_complete(dbs, 0);
-}
-
-static const AIOCBInfo dma_aiocb_info = {
- .aiocb_size = sizeof(DMAAIOCB),
- .cancel = dma_aio_cancel,
-};
-
-BlockDriverAIOCB *dma_bdrv_io(
- BlockDriverState *bs, QEMUSGList *sg, uint64_t sector_num,
- DMAIOFunc *io_func, BlockDriverCompletionFunc *cb,
- void *opaque, DMADirection dir)
-{
- DMAAIOCB *dbs = qemu_aio_get(&dma_aiocb_info, bs, cb, opaque);
-
- trace_dma_bdrv_io(dbs, bs, sector_num, (dir == DMA_DIRECTION_TO_DEVICE));
-
- dbs->acb = NULL;
- dbs->bs = bs;
- dbs->sg = sg;
- dbs->sector_num = sector_num;
- dbs->sg_cur_index = 0;
- dbs->sg_cur_byte = 0;
- dbs->dir = dir;
- dbs->io_func = io_func;
- dbs->bh = NULL;
- qemu_iovec_init(&dbs->iov, sg->nsg);
- dma_bdrv_cb(dbs, 0);
- return &dbs->common;
-}
-
-
-BlockDriverAIOCB *dma_bdrv_read(BlockDriverState *bs,
- QEMUSGList *sg, uint64_t sector,
- void (*cb)(void *opaque, int ret), void *opaque)
-{
- return dma_bdrv_io(bs, sg, sector, bdrv_aio_readv, cb, opaque,
- DMA_DIRECTION_FROM_DEVICE);
-}
-
-BlockDriverAIOCB *dma_bdrv_write(BlockDriverState *bs,
- QEMUSGList *sg, uint64_t sector,
- void (*cb)(void *opaque, int ret), void *opaque)
-{
- return dma_bdrv_io(bs, sg, sector, bdrv_aio_writev, 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->dma, 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(BlockDriverState *bs, BlockAcctCookie *cookie,
- QEMUSGList *sg, enum BlockAcctType type)
-{
- bdrv_acct_start(bs, cookie, sg->size, type);
-}
-
-bool iommu_dma_memory_valid(DMAContext *dma, dma_addr_t addr, dma_addr_t len,
- DMADirection dir)
-{
- hwaddr paddr, plen;
-
-#ifdef DEBUG_IOMMU
- fprintf(stderr, "dma_memory_check context=%p addr=0x" DMA_ADDR_FMT
- " len=0x" DMA_ADDR_FMT " dir=%d\n", dma, addr, len, dir);
-#endif
-
- while (len) {
- if (dma->translate(dma, addr, &paddr, &plen, dir) != 0) {
- return false;
- }
-
- /* The translation might be valid for larger regions. */
- if (plen > len) {
- plen = len;
- }
-
- len -= plen;
- addr += plen;
- }
-
- return true;
-}
-
-int iommu_dma_memory_rw(DMAContext *dma, dma_addr_t addr,
- void *buf, dma_addr_t len, DMADirection dir)
-{
- hwaddr paddr, plen;
- int err;
-
-#ifdef DEBUG_IOMMU
- fprintf(stderr, "dma_memory_rw context=%p addr=0x" DMA_ADDR_FMT " len=0x"
- DMA_ADDR_FMT " dir=%d\n", dma, addr, len, dir);
-#endif
-
- while (len) {
- err = dma->translate(dma, addr, &paddr, &plen, dir);
- if (err) {
- /*
- * In case of failure on reads from the guest, we clean the
- * destination buffer so that a device that doesn't test
- * for errors will not expose qemu internal memory.
- */
- memset(buf, 0, len);
- return -1;
- }
-
- /* The translation might be valid for larger regions. */
- if (plen > len) {
- plen = len;
- }
-
- address_space_rw(dma->as, paddr, buf, plen, dir == DMA_DIRECTION_FROM_DEVICE);
-
- len -= plen;
- addr += plen;
- buf += plen;
- }
-
- return 0;
-}
-
-int iommu_dma_memory_set(DMAContext *dma, dma_addr_t addr, uint8_t c,
- dma_addr_t len)
-{
- hwaddr paddr, plen;
- int err;
-
-#ifdef DEBUG_IOMMU
- fprintf(stderr, "dma_memory_set context=%p addr=0x" DMA_ADDR_FMT
- " len=0x" DMA_ADDR_FMT "\n", dma, addr, len);
-#endif
-
- while (len) {
- err = dma->translate(dma, addr, &paddr, &plen,
- DMA_DIRECTION_FROM_DEVICE);
- if (err) {
- return err;
- }
-
- /* The translation might be valid for larger regions. */
- if (plen > len) {
- plen = len;
- }
-
- do_dma_memory_set(dma->as, paddr, c, plen);
-
- len -= plen;
- addr += plen;
- }
-
- return 0;
-}
-
-void dma_context_init(DMAContext *dma, AddressSpace *as, DMATranslateFunc translate,
- DMAMapFunc map, DMAUnmapFunc unmap)
-{
-#ifdef DEBUG_IOMMU
- fprintf(stderr, "dma_context_init(%p, %p, %p, %p)\n",
- dma, translate, map, unmap);
-#endif
- dma->as = as;
- dma->translate = translate;
- dma->map = map;
- dma->unmap = unmap;
-}
-
-void *iommu_dma_memory_map(DMAContext *dma, dma_addr_t addr, dma_addr_t *len,
- DMADirection dir)
-{
- int err;
- hwaddr paddr, plen;
- void *buf;
-
- if (dma->map) {
- return dma->map(dma, addr, len, dir);
- }
-
- plen = *len;
- err = dma->translate(dma, addr, &paddr, &plen, dir);
- if (err) {
- return NULL;
- }
-
- /*
- * If this is true, the virtual region is contiguous,
- * but the translated physical region isn't. We just
- * clamp *len, much like address_space_map() does.
- */
- if (plen < *len) {
- *len = plen;
- }
-
- buf = address_space_map(dma->as, paddr, &plen, dir == DMA_DIRECTION_FROM_DEVICE);
- *len = plen;
-
- return buf;
-}
-
-void iommu_dma_memory_unmap(DMAContext *dma, void *buffer, dma_addr_t len,
- DMADirection dir, dma_addr_t access_len)
-{
- if (dma->unmap) {
- dma->unmap(dma, buffer, len, dir, access_len);
- return;
- }
-
- address_space_unmap(dma->as, buffer, len, dir == DMA_DIRECTION_FROM_DEVICE,
- access_len);
-
-}
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