hw/usb/libhw.c

   1 /*
   2  * QEMU USB emulation, libhw bits.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  20  * THE SOFTWARE.
  21  */
  22 #include "qemu/osdep.h"
  23 #include "hw/usb.h"
  24 #include "sysemu/dma.h"
  25
  26 int usb_packet_map(USBPacket *p, QEMUSGList *sgl)
  27 {
  28     DMADirection dir = (p->pid == USB_TOKEN_IN) ?
  29         DMA_DIRECTION_FROM_DEVICE : DMA_DIRECTION_TO_DEVICE;
  30     void *mem;
  31     int i;
  32
  33     for (i = 0; i < sgl->nsg; i++) {
  34         dma_addr_t base = sgl->sg[i].base;
  35         dma_addr_t len = sgl->sg[i].len;
  36
  37         while (len) {
  38             dma_addr_t xlen = len;
  39             mem = dma_memory_map(sgl->as, base, &xlen, dir);
  40             if (!mem) {
  41                 goto err;
  42             }
  43             if (xlen > len) {
  44                 xlen = len;
  45             }
  46             qemu_iovec_add(&p->iov, mem, xlen);
  47             len -= xlen;
  48             base += xlen;
  49         }
  50     }
  51     return 0;
  52
  53 err:
  54     usb_packet_unmap(p, sgl);
  55     return -1;
  56 }
  57
  58 void usb_packet_unmap(USBPacket *p, QEMUSGList *sgl)
  59 {
  60     DMADirection dir = (p->pid == USB_TOKEN_IN) ?
  61         DMA_DIRECTION_FROM_DEVICE : DMA_DIRECTION_TO_DEVICE;
  62     int i;
  63
  64     for (i = 0; i < p->iov.niov; i++) {
  65         dma_memory_unmap(sgl->as, p->iov.iov[i].iov_base,
  66                          p->iov.iov[i].iov_len, dir,
  67                          p->iov.iov[i].iov_len);
  68     }
  69 }