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
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/module.h>
29 #include <linux/pci.h>
30 #include <linux/stat.h>
31 #include <linux/dmar.h>
32 #include <linux/iommu.h>
33 #include <linux/intel-iommu.h>
35 static bool allow_unsafe_assigned_interrupts;
36 module_param_named(allow_unsafe_assigned_interrupts,
37 allow_unsafe_assigned_interrupts, bool, S_IRUGO | S_IWUSR);
38 MODULE_PARM_DESC(allow_unsafe_assigned_interrupts,
39 "Enable device assignment on platforms without interrupt remapping support.");
41 static int kvm_iommu_unmap_memslots(struct kvm *kvm);
42 static void kvm_iommu_put_pages(struct kvm *kvm,
43 gfn_t base_gfn, unsigned long npages);
45 static pfn_t kvm_pin_pages(struct kvm_memory_slot *slot, gfn_t gfn,
51 pfn = gfn_to_pfn_memslot(slot, gfn);
52 end_gfn = gfn + (size >> PAGE_SHIFT);
55 if (is_error_noslot_pfn(pfn))
59 gfn_to_pfn_memslot(slot, gfn++);
64 int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
69 struct iommu_domain *domain = kvm->arch.iommu_domain;
72 /* check if iommu exists and in use */
77 end_gfn = gfn + slot->npages;
80 if (!(slot->flags & KVM_MEM_READONLY))
82 if (!kvm->arch.iommu_noncoherent)
86 while (gfn < end_gfn) {
87 unsigned long page_size;
89 /* Check if already mapped */
90 if (iommu_iova_to_phys(domain, gfn_to_gpa(gfn))) {
95 /* Get the page size we could use to map */
96 page_size = kvm_host_page_size(kvm, gfn);
98 /* Make sure the page_size does not exceed the memslot */
99 while ((gfn + (page_size >> PAGE_SHIFT)) > end_gfn)
102 /* Make sure gfn is aligned to the page size we want to map */
103 while ((gfn << PAGE_SHIFT) & (page_size - 1))
107 * Pin all pages we are about to map in memory. This is
108 * important because we unmap and unpin in 4kb steps later.
110 pfn = kvm_pin_pages(slot, gfn, page_size);
111 if (is_error_noslot_pfn(pfn)) {
116 /* Map into IO address space */
117 r = iommu_map(domain, gfn_to_gpa(gfn), pfn_to_hpa(pfn),
120 printk(KERN_ERR "kvm_iommu_map_address:"
121 "iommu failed to map pfn=%llx\n", pfn);
125 gfn += page_size >> PAGE_SHIFT;
133 kvm_iommu_put_pages(kvm, slot->base_gfn, gfn);
137 static int kvm_iommu_map_memslots(struct kvm *kvm)
140 struct kvm_memslots *slots;
141 struct kvm_memory_slot *memslot;
143 if (kvm->arch.iommu_noncoherent)
144 kvm_arch_register_noncoherent_dma(kvm);
146 idx = srcu_read_lock(&kvm->srcu);
147 slots = kvm_memslots(kvm);
149 kvm_for_each_memslot(memslot, slots) {
150 r = kvm_iommu_map_pages(kvm, memslot);
154 srcu_read_unlock(&kvm->srcu, idx);
159 int kvm_assign_device(struct kvm *kvm,
160 struct kvm_assigned_dev_kernel *assigned_dev)
162 struct pci_dev *pdev = NULL;
163 struct iommu_domain *domain = kvm->arch.iommu_domain;
167 /* check if iommu exists and in use */
171 pdev = assigned_dev->dev;
175 r = iommu_attach_device(domain, &pdev->dev);
177 dev_err(&pdev->dev, "kvm assign device failed ret %d", r);
181 noncoherent = !iommu_domain_has_cap(kvm->arch.iommu_domain,
182 IOMMU_CAP_CACHE_COHERENCY);
184 /* Check if need to update IOMMU page table for guest memory */
185 if (noncoherent != kvm->arch.iommu_noncoherent) {
186 kvm_iommu_unmap_memslots(kvm);
187 kvm->arch.iommu_noncoherent = noncoherent;
188 r = kvm_iommu_map_memslots(kvm);
193 pdev->dev_flags |= PCI_DEV_FLAGS_ASSIGNED;
195 dev_info(&pdev->dev, "kvm assign device\n");
199 kvm_iommu_unmap_memslots(kvm);
203 int kvm_deassign_device(struct kvm *kvm,
204 struct kvm_assigned_dev_kernel *assigned_dev)
206 struct iommu_domain *domain = kvm->arch.iommu_domain;
207 struct pci_dev *pdev = NULL;
209 /* check if iommu exists and in use */
213 pdev = assigned_dev->dev;
217 iommu_detach_device(domain, &pdev->dev);
219 pdev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
221 dev_info(&pdev->dev, "kvm deassign device\n");
226 int kvm_iommu_map_guest(struct kvm *kvm)
230 if (!iommu_present(&pci_bus_type)) {
231 printk(KERN_ERR "%s: iommu not found\n", __func__);
235 mutex_lock(&kvm->slots_lock);
237 kvm->arch.iommu_domain = iommu_domain_alloc(&pci_bus_type);
238 if (!kvm->arch.iommu_domain) {
243 if (!allow_unsafe_assigned_interrupts &&
244 !iommu_domain_has_cap(kvm->arch.iommu_domain,
245 IOMMU_CAP_INTR_REMAP)) {
246 printk(KERN_WARNING "%s: No interrupt remapping support,"
247 " disallowing device assignment."
248 " Re-enble with \"allow_unsafe_assigned_interrupts=1\""
249 " module option.\n", __func__);
250 iommu_domain_free(kvm->arch.iommu_domain);
251 kvm->arch.iommu_domain = NULL;
256 r = kvm_iommu_map_memslots(kvm);
258 kvm_iommu_unmap_memslots(kvm);
261 mutex_unlock(&kvm->slots_lock);
265 static void kvm_unpin_pages(struct kvm *kvm, pfn_t pfn, unsigned long npages)
269 for (i = 0; i < npages; ++i)
270 kvm_release_pfn_clean(pfn + i);
273 static void kvm_iommu_put_pages(struct kvm *kvm,
274 gfn_t base_gfn, unsigned long npages)
276 struct iommu_domain *domain;
281 domain = kvm->arch.iommu_domain;
282 end_gfn = base_gfn + npages;
285 /* check if iommu exists and in use */
289 while (gfn < end_gfn) {
290 unsigned long unmap_pages;
293 /* Get physical address */
294 phys = iommu_iova_to_phys(domain, gfn_to_gpa(gfn));
301 pfn = phys >> PAGE_SHIFT;
303 /* Unmap address from IO address space */
304 size = iommu_unmap(domain, gfn_to_gpa(gfn), PAGE_SIZE);
305 unmap_pages = 1ULL << get_order(size);
307 /* Unpin all pages we just unmapped to not leak any memory */
308 kvm_unpin_pages(kvm, pfn, unmap_pages);
314 void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
316 kvm_iommu_put_pages(kvm, slot->base_gfn, slot->npages);
319 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
322 struct kvm_memslots *slots;
323 struct kvm_memory_slot *memslot;
325 idx = srcu_read_lock(&kvm->srcu);
326 slots = kvm_memslots(kvm);
328 kvm_for_each_memslot(memslot, slots)
329 kvm_iommu_unmap_pages(kvm, memslot);
331 srcu_read_unlock(&kvm->srcu, idx);
333 if (kvm->arch.iommu_noncoherent)
334 kvm_arch_unregister_noncoherent_dma(kvm);
339 int kvm_iommu_unmap_guest(struct kvm *kvm)
341 struct iommu_domain *domain = kvm->arch.iommu_domain;
343 /* check if iommu exists and in use */
347 mutex_lock(&kvm->slots_lock);
348 kvm_iommu_unmap_memslots(kvm);
349 kvm->arch.iommu_domain = NULL;
350 kvm->arch.iommu_noncoherent = false;
351 mutex_unlock(&kvm->slots_lock);
353 iommu_domain_free(domain);