virt/kvm/iommu.c

   1 /*
   2  * Copyright (c) 2006, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Copyright (C) 2006-2008 Intel Corporation
  18  * Copyright IBM Corporation, 2008
  19  * Author: Allen M. Kay <allen.m.kay@intel.com>
  20  * Author: Weidong Han <weidong.han@intel.com>
  21  * Author: Ben-Ami Yassour <benami@il.ibm.com>
  22  */
  23
  24 #include <linux/list.h>
  25 #include <linux/kvm_host.h>
  26 #include <linux/pci.h>
  27 #include <linux/dmar.h>
  28 #include <linux/iommu.h>
  29 #include <linux/intel-iommu.h>
  30
  31 static int kvm_iommu_unmap_memslots(struct kvm *kvm);
  32 static void kvm_iommu_put_pages(struct kvm *kvm,
  33                                 gfn_t base_gfn, unsigned long npages);
  34
  35 int kvm_iommu_map_pages(struct kvm *kvm,
  36                         gfn_t base_gfn, unsigned long npages)
  37 {
  38         gfn_t gfn = base_gfn;
  39         pfn_t pfn;
  40         int i, r = 0;
  41         struct iommu_domain *domain = kvm->arch.iommu_domain;
  42
  43         /* check if iommu exists and in use */
  44         if (!domain)
  45                 return 0;
  46
  47         for (i = 0; i < npages; i++) {
  48                 /* check if already mapped */
  49                 if (iommu_iova_to_phys(domain, gfn_to_gpa(gfn)))
  50                         continue;
  51
  52                 pfn = gfn_to_pfn(kvm, gfn);
  53                 r = iommu_map_range(domain,
  54                                     gfn_to_gpa(gfn),
  55                                     pfn_to_hpa(pfn),
  56                                     PAGE_SIZE,
  57                                     IOMMU_READ | IOMMU_WRITE);
  58                 if (r) {
  59                         printk(KERN_ERR "kvm_iommu_map_address:"
  60                                "iommu failed to map pfn=%lx\n", pfn);
  61                         goto unmap_pages;
  62                 }
  63                 gfn++;
  64         }
  65         return 0;
  66
  67 unmap_pages:
  68         kvm_iommu_put_pages(kvm, base_gfn, i);
  69         return r;
  70 }
  71
  72 static int kvm_iommu_map_memslots(struct kvm *kvm)
  73 {
  74         int i, r = 0;
  75
  76         for (i = 0; i < kvm->nmemslots; i++) {
  77                 r = kvm_iommu_map_pages(kvm, kvm->memslots[i].base_gfn,
  78                                         kvm->memslots[i].npages);
  79                 if (r)
  80                         break;
  81         }
  82
  83         return r;
  84 }
  85
  86 int kvm_assign_device(struct kvm *kvm,
  87                       struct kvm_assigned_dev_kernel *assigned_dev)
  88 {
  89         struct pci_dev *pdev = NULL;
  90         struct iommu_domain *domain = kvm->arch.iommu_domain;
  91         int r;
  92
  93         /* check if iommu exists and in use */
  94         if (!domain)
  95                 return 0;
  96
  97         pdev = assigned_dev->dev;
  98         if (pdev == NULL)
  99                 return -ENODEV;
 100
 101         r = iommu_attach_device(domain, &pdev->dev);
 102         if (r) {
 103                 printk(KERN_ERR "assign device %x:%x.%x failed",
 104                         pdev->bus->number,
 105                         PCI_SLOT(pdev->devfn),
 106                         PCI_FUNC(pdev->devfn));
 107                 return r;
 108         }
 109
 110         printk(KERN_DEBUG "assign device: host bdf = %x:%x:%x\n",
 111                 assigned_dev->host_busnr,
 112                 PCI_SLOT(assigned_dev->host_devfn),
 113                 PCI_FUNC(assigned_dev->host_devfn));
 114
 115         return 0;
 116 }
 117
 118 int kvm_deassign_device(struct kvm *kvm,
 119                         struct kvm_assigned_dev_kernel *assigned_dev)
 120 {
 121         struct iommu_domain *domain = kvm->arch.iommu_domain;
 122         struct pci_dev *pdev = NULL;
 123
 124         /* check if iommu exists and in use */
 125         if (!domain)
 126                 return 0;
 127
 128         pdev = assigned_dev->dev;
 129         if (pdev == NULL)
 130                 return -ENODEV;
 131
 132         iommu_detach_device(domain, &pdev->dev);
 133
 134         printk(KERN_DEBUG "deassign device: host bdf = %x:%x:%x\n",
 135                 assigned_dev->host_busnr,
 136                 PCI_SLOT(assigned_dev->host_devfn),
 137                 PCI_FUNC(assigned_dev->host_devfn));
 138
 139         return 0;
 140 }
 141
 142 int kvm_iommu_map_guest(struct kvm *kvm)
 143 {
 144         int r;
 145
 146         if (!iommu_found()) {
 147                 printk(KERN_ERR "%s: iommu not found\n", __func__);
 148                 return -ENODEV;
 149         }
 150
 151         kvm->arch.iommu_domain = iommu_domain_alloc();
 152         if (!kvm->arch.iommu_domain)
 153                 return -ENOMEM;
 154
 155         r = kvm_iommu_map_memslots(kvm);
 156         if (r)
 157                 goto out_unmap;
 158
 159         return 0;
 160
 161 out_unmap:
 162         kvm_iommu_unmap_memslots(kvm);
 163         return r;
 164 }
 165
 166 static void kvm_iommu_put_pages(struct kvm *kvm,
 167                                 gfn_t base_gfn, unsigned long npages)
 168 {
 169         gfn_t gfn = base_gfn;
 170         pfn_t pfn;
 171         struct iommu_domain *domain = kvm->arch.iommu_domain;
 172         unsigned long i;
 173         u64 phys;
 174
 175         /* check if iommu exists and in use */
 176         if (!domain)
 177                 return;
 178
 179         for (i = 0; i < npages; i++) {
 180                 phys = iommu_iova_to_phys(domain, gfn_to_gpa(gfn));
 181                 pfn = phys >> PAGE_SHIFT;
 182                 kvm_release_pfn_clean(pfn);
 183                 gfn++;
 184         }
 185
 186         iommu_unmap_range(domain, gfn_to_gpa(base_gfn), PAGE_SIZE * npages);
 187 }
 188
 189 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
 190 {
 191         int i;
 192
 193         for (i = 0; i < kvm->nmemslots; i++) {
 194                 kvm_iommu_put_pages(kvm, kvm->memslots[i].base_gfn,
 195                                     kvm->memslots[i].npages);
 196         }
 197
 198         return 0;
 199 }
 200
 201 int kvm_iommu_unmap_guest(struct kvm *kvm)
 202 {
 203         struct iommu_domain *domain = kvm->arch.iommu_domain;
 204
 205         /* check if iommu exists and in use */
 206         if (!domain)
 207                 return 0;
 208
 209         kvm_iommu_unmap_memslots(kvm);
 210         iommu_domain_free(domain);
 211         return 0;
 212 }