KVM: Device Assignment: Map mmio pages into VT-d page table
[linux-2.6.git] / arch / x86 / 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                 pfn = (pfn_t)intel_iommu_iova_to_pfn(domain,
49                                                      gfn_to_gpa(gfn));
50                 if (pfn)
51                         continue;
52
53                 pfn = gfn_to_pfn(kvm, gfn);
54                 r = intel_iommu_page_mapping(domain,
55                                              gfn_to_gpa(gfn),
56                                              pfn_to_hpa(pfn),
57                                              PAGE_SIZE,
58                                              DMA_PTE_READ |
59                                              DMA_PTE_WRITE);
60                 if (r) {
61                         printk(KERN_ERR "kvm_iommu_map_pages:"
62                                "iommu failed to map pfn=%lx\n", pfn);
63                         goto unmap_pages;
64                 }
65                 gfn++;
66         }
67         return 0;
68
69 unmap_pages:
70         kvm_iommu_put_pages(kvm, base_gfn, i);
71         return r;
72 }
73
74 static int kvm_iommu_map_memslots(struct kvm *kvm)
75 {
76         int i, r;
77
78         down_read(&kvm->slots_lock);
79         for (i = 0; i < kvm->nmemslots; i++) {
80                 r = kvm_iommu_map_pages(kvm, kvm->memslots[i].base_gfn,
81                                         kvm->memslots[i].npages);
82                 if (r)
83                         break;
84         }
85         up_read(&kvm->slots_lock);
86         return r;
87 }
88
89 int kvm_iommu_map_guest(struct kvm *kvm,
90                         struct kvm_assigned_dev_kernel *assigned_dev)
91 {
92         struct pci_dev *pdev = NULL;
93         int r;
94
95         if (!intel_iommu_found()) {
96                 printk(KERN_ERR "%s: intel iommu not found\n", __func__);
97                 return -ENODEV;
98         }
99
100         printk(KERN_DEBUG "VT-d direct map: host bdf = %x:%x:%x\n",
101                assigned_dev->host_busnr,
102                PCI_SLOT(assigned_dev->host_devfn),
103                PCI_FUNC(assigned_dev->host_devfn));
104
105         pdev = assigned_dev->dev;
106
107         if (pdev == NULL) {
108                 if (kvm->arch.intel_iommu_domain) {
109                         intel_iommu_domain_exit(kvm->arch.intel_iommu_domain);
110                         kvm->arch.intel_iommu_domain = NULL;
111                 }
112                 return -ENODEV;
113         }
114
115         kvm->arch.intel_iommu_domain = intel_iommu_domain_alloc(pdev);
116         if (!kvm->arch.intel_iommu_domain)
117                 return -ENODEV;
118
119         r = kvm_iommu_map_memslots(kvm);
120         if (r)
121                 goto out_unmap;
122
123         intel_iommu_detach_dev(kvm->arch.intel_iommu_domain,
124                                pdev->bus->number, pdev->devfn);
125
126         r = intel_iommu_context_mapping(kvm->arch.intel_iommu_domain,
127                                         pdev);
128         if (r) {
129                 printk(KERN_ERR "Domain context map for %s failed",
130                        pci_name(pdev));
131                 goto out_unmap;
132         }
133         return 0;
134
135 out_unmap:
136         kvm_iommu_unmap_memslots(kvm);
137         return r;
138 }
139
140 static void kvm_iommu_put_pages(struct kvm *kvm,
141                                gfn_t base_gfn, unsigned long npages)
142 {
143         gfn_t gfn = base_gfn;
144         pfn_t pfn;
145         struct dmar_domain *domain = kvm->arch.intel_iommu_domain;
146         int i;
147
148         for (i = 0; i < npages; i++) {
149                 pfn = (pfn_t)intel_iommu_iova_to_pfn(domain,
150                                                      gfn_to_gpa(gfn));
151                 kvm_release_pfn_clean(pfn);
152                 gfn++;
153         }
154 }
155
156 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
157 {
158         int i;
159         down_read(&kvm->slots_lock);
160         for (i = 0; i < kvm->nmemslots; i++) {
161                 kvm_iommu_put_pages(kvm, kvm->memslots[i].base_gfn,
162                                     kvm->memslots[i].npages);
163         }
164         up_read(&kvm->slots_lock);
165
166         return 0;
167 }
168
169 int kvm_iommu_unmap_guest(struct kvm *kvm)
170 {
171         struct kvm_assigned_dev_kernel *entry;
172         struct dmar_domain *domain = kvm->arch.intel_iommu_domain;
173
174         /* check if iommu exists and in use */
175         if (!domain)
176                 return 0;
177
178         list_for_each_entry(entry, &kvm->arch.assigned_dev_head, list) {
179                 printk(KERN_DEBUG "VT-d unmap: host bdf = %x:%x:%x\n",
180                        entry->host_busnr,
181                        PCI_SLOT(entry->host_devfn),
182                        PCI_FUNC(entry->host_devfn));
183
184                 /* detach kvm dmar domain */
185                 intel_iommu_detach_dev(domain, entry->host_busnr,
186                                        entry->host_devfn);
187         }
188         kvm_iommu_unmap_memslots(kvm);
189         intel_iommu_domain_exit(domain);
190         return 0;
191 }