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         int flags;
  43
  44         /* check if iommu exists and in use */
  45         if (!domain)
  46                 return 0;
  47
  48         flags = IOMMU_READ | IOMMU_WRITE;
  49         if (kvm->arch.iommu_flags & KVM_IOMMU_CACHE_COHERENCY)
  50                 flags |= IOMMU_CACHE;
  51
  52         for (i = 0; i < npages; i++) {
  53                 /* check if already mapped */
  54                 if (iommu_iova_to_phys(domain, gfn_to_gpa(gfn)))
  55                         continue;
  56
  57                 pfn = gfn_to_pfn(kvm, gfn);
  58                 r = iommu_map_range(domain,
  59                                     gfn_to_gpa(gfn),
  60                                     pfn_to_hpa(pfn),
  61                                     PAGE_SIZE, flags);
  62                 if (r) {
  63                         printk(KERN_ERR "kvm_iommu_map_address:"
  64                                "iommu failed to map pfn=%lx\n", pfn);
  65                         goto unmap_pages;
  66                 }
  67                 gfn++;
  68         }
  69         return 0;
  70
  71 unmap_pages:
  72         kvm_iommu_put_pages(kvm, base_gfn, i);
  73         return r;
  74 }
  75
  76 static int kvm_iommu_map_memslots(struct kvm *kvm)
  77 {
  78         int i, r = 0;
  79         struct kvm_memslots *slots;
  80
  81         slots = kvm->memslots;
  82
  83         for (i = 0; i < slots->nmemslots; i++) {
  84                 r = kvm_iommu_map_pages(kvm, slots->memslots[i].base_gfn,
  85                                         slots->memslots[i].npages);
  86                 if (r)
  87                         break;
  88         }
  89
  90         return r;
  91 }
  92
  93 int kvm_assign_device(struct kvm *kvm,
  94                       struct kvm_assigned_dev_kernel *assigned_dev)
  95 {
  96         struct pci_dev *pdev = NULL;
  97         struct iommu_domain *domain = kvm->arch.iommu_domain;
  98         int r, last_flags;
  99
 100         /* check if iommu exists and in use */
 101         if (!domain)
 102                 return 0;
 103
 104         pdev = assigned_dev->dev;
 105         if (pdev == NULL)
 106                 return -ENODEV;
 107
 108         r = iommu_attach_device(domain, &pdev->dev);
 109         if (r) {
 110                 printk(KERN_ERR "assign device %x:%x.%x failed",
 111                         pdev->bus->number,
 112                         PCI_SLOT(pdev->devfn),
 113                         PCI_FUNC(pdev->devfn));
 114                 return r;
 115         }
 116
 117         last_flags = kvm->arch.iommu_flags;
 118         if (iommu_domain_has_cap(kvm->arch.iommu_domain,
 119                                  IOMMU_CAP_CACHE_COHERENCY))
 120                 kvm->arch.iommu_flags |= KVM_IOMMU_CACHE_COHERENCY;
 121
 122         /* Check if need to update IOMMU page table for guest memory */
 123         if ((last_flags ^ kvm->arch.iommu_flags) ==
 124                         KVM_IOMMU_CACHE_COHERENCY) {
 125                 kvm_iommu_unmap_memslots(kvm);
 126                 r = kvm_iommu_map_memslots(kvm);
 127                 if (r)
 128                         goto out_unmap;
 129         }
 130
 131         printk(KERN_DEBUG "assign device: host bdf = %x:%x:%x\n",
 132                 assigned_dev->host_busnr,
 133                 PCI_SLOT(assigned_dev->host_devfn),
 134                 PCI_FUNC(assigned_dev->host_devfn));
 135
 136         return 0;
 137 out_unmap:
 138         kvm_iommu_unmap_memslots(kvm);
 139         return r;
 140 }
 141
 142 int kvm_deassign_device(struct kvm *kvm,
 143                         struct kvm_assigned_dev_kernel *assigned_dev)
 144 {
 145         struct iommu_domain *domain = kvm->arch.iommu_domain;
 146         struct pci_dev *pdev = NULL;
 147
 148         /* check if iommu exists and in use */
 149         if (!domain)
 150                 return 0;
 151
 152         pdev = assigned_dev->dev;
 153         if (pdev == NULL)
 154                 return -ENODEV;
 155
 156         iommu_detach_device(domain, &pdev->dev);
 157
 158         printk(KERN_DEBUG "deassign device: host bdf = %x:%x:%x\n",
 159                 assigned_dev->host_busnr,
 160                 PCI_SLOT(assigned_dev->host_devfn),
 161                 PCI_FUNC(assigned_dev->host_devfn));
 162
 163         return 0;
 164 }
 165
 166 int kvm_iommu_map_guest(struct kvm *kvm)
 167 {
 168         int r;
 169
 170         if (!iommu_found()) {
 171                 printk(KERN_ERR "%s: iommu not found\n", __func__);
 172                 return -ENODEV;
 173         }
 174
 175         kvm->arch.iommu_domain = iommu_domain_alloc();
 176         if (!kvm->arch.iommu_domain)
 177                 return -ENOMEM;
 178
 179         r = kvm_iommu_map_memslots(kvm);
 180         if (r)
 181                 goto out_unmap;
 182
 183         return 0;
 184
 185 out_unmap:
 186         kvm_iommu_unmap_memslots(kvm);
 187         return r;
 188 }
 189
 190 static void kvm_iommu_put_pages(struct kvm *kvm,
 191                                 gfn_t base_gfn, unsigned long npages)
 192 {
 193         gfn_t gfn = base_gfn;
 194         pfn_t pfn;
 195         struct iommu_domain *domain = kvm->arch.iommu_domain;
 196         unsigned long i;
 197         u64 phys;
 198
 199         /* check if iommu exists and in use */
 200         if (!domain)
 201                 return;
 202
 203         for (i = 0; i < npages; i++) {
 204                 phys = iommu_iova_to_phys(domain, gfn_to_gpa(gfn));
 205                 pfn = phys >> PAGE_SHIFT;
 206                 kvm_release_pfn_clean(pfn);
 207                 gfn++;
 208         }
 209
 210         iommu_unmap_range(domain, gfn_to_gpa(base_gfn), PAGE_SIZE * npages);
 211 }
 212
 213 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
 214 {
 215         int i;
 216         struct kvm_memslots *slots;
 217
 218         slots = kvm->memslots;
 219
 220         for (i = 0; i < slots->nmemslots; i++) {
 221                 kvm_iommu_put_pages(kvm, slots->memslots[i].base_gfn,
 222                                     slots->memslots[i].npages);
 223         }
 224
 225         return 0;
 226 }
 227
 228 int kvm_iommu_unmap_guest(struct kvm *kvm)
 229 {
 230         struct iommu_domain *domain = kvm->arch.iommu_domain;
 231
 232         /* check if iommu exists and in use */
 233         if (!domain)
 234                 return 0;
 235
 236         kvm_iommu_unmap_memslots(kvm);
 237         iommu_domain_free(domain);
 238         return 0;
 239 }