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         down_read(&kvm->slots_lock);
  77         for (i = 0; i < kvm->nmemslots; i++) {
  78                 r = kvm_iommu_map_pages(kvm, kvm->memslots[i].base_gfn,
  79                                         kvm->memslots[i].npages);
  80                 if (r)
  81                         break;
  82         }
  83         up_read(&kvm->slots_lock);
  84         return r;
  85 }
  86
  87 int kvm_assign_device(struct kvm *kvm,
  88                       struct kvm_assigned_dev_kernel *assigned_dev)
  89 {
  90         struct pci_dev *pdev = NULL;
  91         struct iommu_domain *domain = kvm->arch.iommu_domain;
  92         int r;
  93
  94         /* check if iommu exists and in use */
  95         if (!domain)
  96                 return 0;
  97
  98         pdev = assigned_dev->dev;
  99         if (pdev == NULL)
 100                 return -ENODEV;
 101
 102         r = iommu_attach_device(domain, &pdev->dev);
 103         if (r) {
 104                 printk(KERN_ERR "assign device %x:%x.%x failed",
 105                         pdev->bus->number,
 106                         PCI_SLOT(pdev->devfn),
 107                         PCI_FUNC(pdev->devfn));
 108                 return r;
 109         }
 110
 111         printk(KERN_DEBUG "assign device: host bdf = %x:%x:%x\n",
 112                 assigned_dev->host_busnr,
 113                 PCI_SLOT(assigned_dev->host_devfn),
 114                 PCI_FUNC(assigned_dev->host_devfn));
 115
 116         return 0;
 117 }
 118
 119 int kvm_deassign_device(struct kvm *kvm,
 120                         struct kvm_assigned_dev_kernel *assigned_dev)
 121 {
 122         struct iommu_domain *domain = kvm->arch.iommu_domain;
 123         struct pci_dev *pdev = NULL;
 124
 125         /* check if iommu exists and in use */
 126         if (!domain)
 127                 return 0;
 128
 129         pdev = assigned_dev->dev;
 130         if (pdev == NULL)
 131                 return -ENODEV;
 132
 133         iommu_detach_device(domain, &pdev->dev);
 134
 135         printk(KERN_DEBUG "deassign device: host bdf = %x:%x:%x\n",
 136                 assigned_dev->host_busnr,
 137                 PCI_SLOT(assigned_dev->host_devfn),
 138                 PCI_FUNC(assigned_dev->host_devfn));
 139
 140         return 0;
 141 }
 142
 143 int kvm_iommu_map_guest(struct kvm *kvm)
 144 {
 145         int r;
 146
 147         if (!iommu_found()) {
 148                 printk(KERN_ERR "%s: iommu not found\n", __func__);
 149                 return -ENODEV;
 150         }
 151
 152         kvm->arch.iommu_domain = iommu_domain_alloc();
 153         if (!kvm->arch.iommu_domain)
 154                 return -ENOMEM;
 155
 156         r = kvm_iommu_map_memslots(kvm);
 157         if (r)
 158                 goto out_unmap;
 159
 160         return 0;
 161
 162 out_unmap:
 163         kvm_iommu_unmap_memslots(kvm);
 164         return r;
 165 }
 166
 167 static void kvm_iommu_put_pages(struct kvm *kvm,
 168                                 gfn_t base_gfn, unsigned long npages)
 169 {
 170         gfn_t gfn = base_gfn;
 171         pfn_t pfn;
 172         struct iommu_domain *domain = kvm->arch.iommu_domain;
 173         unsigned long i;
 174         u64 phys;
 175
 176         /* check if iommu exists and in use */
 177         if (!domain)
 178                 return;
 179
 180         for (i = 0; i < npages; i++) {
 181                 phys = iommu_iova_to_phys(domain, gfn_to_gpa(gfn));
 182                 pfn = phys >> PAGE_SHIFT;
 183                 kvm_release_pfn_clean(pfn);
 184                 gfn++;
 185         }
 186
 187         iommu_unmap_range(domain, gfn_to_gpa(base_gfn), PAGE_SIZE * npages);
 188 }
 189
 190 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
 191 {
 192         int i;
 193         down_read(&kvm->slots_lock);
 194         for (i = 0; i < kvm->nmemslots; i++) {
 195                 kvm_iommu_put_pages(kvm, kvm->memslots[i].base_gfn,
 196                                     kvm->memslots[i].npages);
 197         }
 198         up_read(&kvm->slots_lock);
 199
 200         return 0;
 201 }
 202
 203 int kvm_iommu_unmap_guest(struct kvm *kvm)
 204 {
 205         struct iommu_domain *domain = kvm->arch.iommu_domain;
 206
 207         /* check if iommu exists and in use */
 208         if (!domain)
 209                 return 0;
 210
 211         kvm_iommu_unmap_memslots(kvm);
 212         iommu_domain_free(domain);
 213         return 0;
 214 }