Add linux-next specific files for 20110705
[linux-2.6/next.git] / virt / kvm / iommu.c
blob62a9caf0563c2205327245b2a1103f1bbff94e70
1 /*
2 * Copyright (c) 2006, Intel Corporation.
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.
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.
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.
17 * Copyright (C) 2006-2008 Intel Corporation
18 * Copyright IBM Corporation, 2008
19 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
21 * Author: Allen M. Kay <allen.m.kay@intel.com>
22 * Author: Weidong Han <weidong.han@intel.com>
23 * Author: Ben-Ami Yassour <benami@il.ibm.com>
26 #include <linux/list.h>
27 #include <linux/kvm_host.h>
28 #include <linux/pci.h>
29 #include <linux/dmar.h>
30 #include <linux/iommu.h>
31 #include <linux/intel-iommu.h>
33 static int kvm_iommu_unmap_memslots(struct kvm *kvm);
34 static void kvm_iommu_put_pages(struct kvm *kvm,
35 gfn_t base_gfn, unsigned long npages);
37 static pfn_t kvm_pin_pages(struct kvm *kvm, struct kvm_memory_slot *slot,
38 gfn_t gfn, unsigned long size)
40 gfn_t end_gfn;
41 pfn_t pfn;
43 pfn = gfn_to_pfn_memslot(kvm, slot, gfn);
44 end_gfn = gfn + (size >> PAGE_SHIFT);
45 gfn += 1;
47 if (is_error_pfn(pfn))
48 return pfn;
50 while (gfn < end_gfn)
51 gfn_to_pfn_memslot(kvm, slot, gfn++);
53 return pfn;
56 int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
58 gfn_t gfn, end_gfn;
59 pfn_t pfn;
60 int r = 0;
61 struct iommu_domain *domain = kvm->arch.iommu_domain;
62 int flags;
64 /* check if iommu exists and in use */
65 if (!domain)
66 return 0;
68 gfn = slot->base_gfn;
69 end_gfn = gfn + slot->npages;
71 flags = IOMMU_READ | IOMMU_WRITE;
72 if (kvm->arch.iommu_flags & KVM_IOMMU_CACHE_COHERENCY)
73 flags |= IOMMU_CACHE;
76 while (gfn < end_gfn) {
77 unsigned long page_size;
79 /* Check if already mapped */
80 if (iommu_iova_to_phys(domain, gfn_to_gpa(gfn))) {
81 gfn += 1;
82 continue;
85 /* Get the page size we could use to map */
86 page_size = kvm_host_page_size(kvm, gfn);
88 /* Make sure the page_size does not exceed the memslot */
89 while ((gfn + (page_size >> PAGE_SHIFT)) > end_gfn)
90 page_size >>= 1;
92 /* Make sure gfn is aligned to the page size we want to map */
93 while ((gfn << PAGE_SHIFT) & (page_size - 1))
94 page_size >>= 1;
97 * Pin all pages we are about to map in memory. This is
98 * important because we unmap and unpin in 4kb steps later.
100 pfn = kvm_pin_pages(kvm, slot, gfn, page_size);
101 if (is_error_pfn(pfn)) {
102 gfn += 1;
103 continue;
106 /* Map into IO address space */
107 r = iommu_map(domain, gfn_to_gpa(gfn), pfn_to_hpa(pfn),
108 get_order(page_size), flags);
109 if (r) {
110 printk(KERN_ERR "kvm_iommu_map_address:"
111 "iommu failed to map pfn=%llx\n", pfn);
112 goto unmap_pages;
115 gfn += page_size >> PAGE_SHIFT;
120 return 0;
122 unmap_pages:
123 kvm_iommu_put_pages(kvm, slot->base_gfn, gfn);
124 return r;
127 static int kvm_iommu_map_memslots(struct kvm *kvm)
129 int i, idx, r = 0;
130 struct kvm_memslots *slots;
132 idx = srcu_read_lock(&kvm->srcu);
133 slots = kvm_memslots(kvm);
135 for (i = 0; i < slots->nmemslots; i++) {
136 r = kvm_iommu_map_pages(kvm, &slots->memslots[i]);
137 if (r)
138 break;
140 srcu_read_unlock(&kvm->srcu, idx);
142 return r;
145 int kvm_assign_device(struct kvm *kvm,
146 struct kvm_assigned_dev_kernel *assigned_dev)
148 struct pci_dev *pdev = NULL;
149 struct iommu_domain *domain = kvm->arch.iommu_domain;
150 int r, last_flags;
152 /* check if iommu exists and in use */
153 if (!domain)
154 return 0;
156 pdev = assigned_dev->dev;
157 if (pdev == NULL)
158 return -ENODEV;
160 r = iommu_attach_device(domain, &pdev->dev);
161 if (r) {
162 printk(KERN_ERR "assign device %x:%x:%x.%x failed",
163 pci_domain_nr(pdev->bus),
164 pdev->bus->number,
165 PCI_SLOT(pdev->devfn),
166 PCI_FUNC(pdev->devfn));
167 return r;
170 last_flags = kvm->arch.iommu_flags;
171 if (iommu_domain_has_cap(kvm->arch.iommu_domain,
172 IOMMU_CAP_CACHE_COHERENCY))
173 kvm->arch.iommu_flags |= KVM_IOMMU_CACHE_COHERENCY;
175 /* Check if need to update IOMMU page table for guest memory */
176 if ((last_flags ^ kvm->arch.iommu_flags) ==
177 KVM_IOMMU_CACHE_COHERENCY) {
178 kvm_iommu_unmap_memslots(kvm);
179 r = kvm_iommu_map_memslots(kvm);
180 if (r)
181 goto out_unmap;
184 printk(KERN_DEBUG "assign device %x:%x:%x.%x\n",
185 assigned_dev->host_segnr,
186 assigned_dev->host_busnr,
187 PCI_SLOT(assigned_dev->host_devfn),
188 PCI_FUNC(assigned_dev->host_devfn));
190 return 0;
191 out_unmap:
192 kvm_iommu_unmap_memslots(kvm);
193 return r;
196 int kvm_deassign_device(struct kvm *kvm,
197 struct kvm_assigned_dev_kernel *assigned_dev)
199 struct iommu_domain *domain = kvm->arch.iommu_domain;
200 struct pci_dev *pdev = NULL;
202 /* check if iommu exists and in use */
203 if (!domain)
204 return 0;
206 pdev = assigned_dev->dev;
207 if (pdev == NULL)
208 return -ENODEV;
210 iommu_detach_device(domain, &pdev->dev);
212 printk(KERN_DEBUG "deassign device %x:%x:%x.%x\n",
213 assigned_dev->host_segnr,
214 assigned_dev->host_busnr,
215 PCI_SLOT(assigned_dev->host_devfn),
216 PCI_FUNC(assigned_dev->host_devfn));
218 return 0;
221 int kvm_iommu_map_guest(struct kvm *kvm)
223 int r;
225 if (!iommu_found()) {
226 printk(KERN_ERR "%s: iommu not found\n", __func__);
227 return -ENODEV;
230 kvm->arch.iommu_domain = iommu_domain_alloc();
231 if (!kvm->arch.iommu_domain)
232 return -ENOMEM;
234 r = kvm_iommu_map_memslots(kvm);
235 if (r)
236 goto out_unmap;
238 return 0;
240 out_unmap:
241 kvm_iommu_unmap_memslots(kvm);
242 return r;
245 static void kvm_unpin_pages(struct kvm *kvm, pfn_t pfn, unsigned long npages)
247 unsigned long i;
249 for (i = 0; i < npages; ++i)
250 kvm_release_pfn_clean(pfn + i);
253 static void kvm_iommu_put_pages(struct kvm *kvm,
254 gfn_t base_gfn, unsigned long npages)
256 struct iommu_domain *domain;
257 gfn_t end_gfn, gfn;
258 pfn_t pfn;
259 u64 phys;
261 domain = kvm->arch.iommu_domain;
262 end_gfn = base_gfn + npages;
263 gfn = base_gfn;
265 /* check if iommu exists and in use */
266 if (!domain)
267 return;
269 while (gfn < end_gfn) {
270 unsigned long unmap_pages;
271 int order;
273 /* Get physical address */
274 phys = iommu_iova_to_phys(domain, gfn_to_gpa(gfn));
275 pfn = phys >> PAGE_SHIFT;
277 /* Unmap address from IO address space */
278 order = iommu_unmap(domain, gfn_to_gpa(gfn), 0);
279 unmap_pages = 1ULL << order;
281 /* Unpin all pages we just unmapped to not leak any memory */
282 kvm_unpin_pages(kvm, pfn, unmap_pages);
284 gfn += unmap_pages;
288 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
290 int i, idx;
291 struct kvm_memslots *slots;
293 idx = srcu_read_lock(&kvm->srcu);
294 slots = kvm_memslots(kvm);
296 for (i = 0; i < slots->nmemslots; i++) {
297 kvm_iommu_put_pages(kvm, slots->memslots[i].base_gfn,
298 slots->memslots[i].npages);
300 srcu_read_unlock(&kvm->srcu, idx);
302 return 0;
305 int kvm_iommu_unmap_guest(struct kvm *kvm)
307 struct iommu_domain *domain = kvm->arch.iommu_domain;
309 /* check if iommu exists and in use */
310 if (!domain)
311 return 0;
313 kvm_iommu_unmap_memslots(kvm);
314 iommu_domain_free(domain);
315 return 0;