KVM: support device deassignment
[safe/jmp/linux-2.6] / virt / kvm / vtd.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/intel-iommu.h>
29
30 static int kvm_iommu_unmap_memslots(struct kvm *kvm);
31 static void kvm_iommu_put_pages(struct kvm *kvm,
32                                 gfn_t base_gfn, unsigned long npages);
33
34 int kvm_iommu_map_pages(struct kvm *kvm,
35                         gfn_t base_gfn, unsigned long npages)
36 {
37         gfn_t gfn = base_gfn;
38         pfn_t pfn;
39         int i, r = 0;
40         struct dmar_domain *domain = kvm->arch.intel_iommu_domain;
41
42         /* check if iommu exists and in use */
43         if (!domain)
44                 return 0;
45
46         for (i = 0; i < npages; i++) {
47                 /* check if already mapped */
48                 if (intel_iommu_iova_to_phys(domain,
49                                              gfn_to_gpa(gfn)))
50                         continue;
51
52                 pfn = gfn_to_pfn(kvm, gfn);
53                 r = intel_iommu_map_address(domain,
54                                             gfn_to_gpa(gfn),
55                                             pfn_to_hpa(pfn),
56                                             PAGE_SIZE,
57                                             DMA_PTE_READ | DMA_PTE_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;
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 dmar_domain *domain = kvm->arch.intel_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 = intel_iommu_attach_device(domain, pdev);
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 dmar_domain *domain = kvm->arch.intel_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         intel_iommu_detach_device(domain, pdev);
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 (!intel_iommu_found()) {
148                 printk(KERN_ERR "%s: intel iommu not found\n", __func__);
149                 return -ENODEV;
150         }
151
152         kvm->arch.intel_iommu_domain = intel_iommu_alloc_domain();
153         if (!kvm->arch.intel_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 dmar_domain *domain = kvm->arch.intel_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 = intel_iommu_iova_to_phys(domain,
182                                                 gfn_to_gpa(gfn));
183                 pfn = phys >> PAGE_SHIFT;
184                 kvm_release_pfn_clean(pfn);
185                 gfn++;
186         }
187
188         intel_iommu_unmap_address(domain,
189                                   gfn_to_gpa(base_gfn),
190                                   PAGE_SIZE * npages);
191 }
192
193 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
194 {
195         int i;
196         down_read(&kvm->slots_lock);
197         for (i = 0; i < kvm->nmemslots; i++) {
198                 kvm_iommu_put_pages(kvm, kvm->memslots[i].base_gfn,
199                                     kvm->memslots[i].npages);
200         }
201         up_read(&kvm->slots_lock);
202
203         return 0;
204 }
205
206 int kvm_iommu_unmap_guest(struct kvm *kvm)
207 {
208         struct kvm_assigned_dev_kernel *entry;
209         struct dmar_domain *domain = kvm->arch.intel_iommu_domain;
210
211         /* check if iommu exists and in use */
212         if (!domain)
213                 return 0;
214
215         list_for_each_entry(entry, &kvm->arch.assigned_dev_head, list) {
216                 printk(KERN_DEBUG "VT-d unmap: host bdf = %x:%x:%x\n",
217                        entry->host_busnr,
218                        PCI_SLOT(entry->host_devfn),
219                        PCI_FUNC(entry->host_devfn));
220
221                 /* detach kvm dmar domain */
222                 intel_iommu_detach_device(domain, entry->dev);
223         }
224         kvm_iommu_unmap_memslots(kvm);
225         intel_iommu_free_domain(domain);
226         return 0;
227 }