hw/iommu.c

   1 /*
   2  * Generic IOMMU layer
   3  *
   4  * Copyright (c) 2010 Eduard - Gabriel Munteanu
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include <errno.h>
  26
  27 #include "iommu.h"
  28
  29 struct iommu *iommu_get(DeviceState *dev, DeviceState **real_dev)
  30 {
  31     BusState *bus;
  32
  33     while (dev) {
  34         bus = dev->parent_bus;
  35         if (!bus)
  36             goto out;
  37
  38         if (bus->iommu) {
  39             *real_dev = dev;
  40             return bus->iommu;
  41         }
  42
  43         dev = bus->parent;
  44     }
  45
  46 out:
  47     *real_dev = NULL;
  48     return NULL;
  49 }
  50
  51 int __iommu_rw(struct iommu *iommu,
  52                DeviceState *dev,
  53                target_phys_addr_t addr,
  54                uint8_t *buf,
  55                int len,
  56                int is_write)
  57 {
  58     int plen, err;
  59     target_phys_addr_t paddr;
  60     unsigned perms;
  61
  62     if (!is_write)
  63         perms = IOMMU_PERM_READ;
  64     else
  65         perms = IOMMU_PERM_WRITE;
  66
  67     do {
  68         err = iommu->translate(iommu, dev, addr, &paddr, &plen, perms);
  69         if (err)
  70             return err;
  71         if (plen > len)
  72             plen = len;
  73
  74         cpu_physical_memory_rw(paddr, buf, plen, is_write);
  75
  76         len -= plen;
  77         addr += plen;
  78         buf += plen;
  79     } while (len);
  80
  81     return 0;
  82 }