1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * ACRN: Memory mapping management
4 *
5 * Copyright (C) 2020 Intel Corporation. All rights reserved.
6 *
7 * Authors:
8 * Fei Li <lei1.li@intel.com>
9 * Shuo Liu <shuo.a.liu@intel.com>
10 */
11
12 #include <linux/io.h>
13 #include <linux/mm.h>
14 #include <linux/slab.h>
15
16 #include "acrn_drv.h"
17
modify_region(struct acrn_vm * vm,struct vm_memory_region_op * region)18 static int modify_region(struct acrn_vm *vm, struct vm_memory_region_op *region)
19 {
20 struct vm_memory_region_batch *regions;
21 int ret;
22
23 regions = kzalloc(sizeof(*regions), GFP_KERNEL);
24 if (!regions)
25 return -ENOMEM;
26
27 regions->vmid = vm->vmid;
28 regions->regions_num = 1;
29 regions->regions_gpa = virt_to_phys(region);
30
31 ret = hcall_set_memory_regions(virt_to_phys(regions));
32 if (ret < 0)
33 dev_dbg(acrn_dev.this_device,
34 "Failed to set memory region for VM[%u]!\n", vm->vmid);
35
36 kfree(regions);
37 return ret;
38 }
39
40 /**
41 * acrn_mm_region_add() - Set up the EPT mapping of a memory region.
42 * @vm: User VM.
43 * @user_gpa: A GPA of User VM.
44 * @service_gpa: A GPA of Service VM.
45 * @size: Size of the region.
46 * @mem_type: Combination of ACRN_MEM_TYPE_*.
47 * @mem_access_right: Combination of ACRN_MEM_ACCESS_*.
48 *
49 * Return: 0 on success, <0 on error.
50 */
acrn_mm_region_add(struct acrn_vm * vm,u64 user_gpa,u64 service_gpa,u64 size,u32 mem_type,u32 mem_access_right)51 int acrn_mm_region_add(struct acrn_vm *vm, u64 user_gpa, u64 service_gpa,
52 u64 size, u32 mem_type, u32 mem_access_right)
53 {
54 struct vm_memory_region_op *region;
55 int ret = 0;
56
57 region = kzalloc(sizeof(*region), GFP_KERNEL);
58 if (!region)
59 return -ENOMEM;
60
61 region->type = ACRN_MEM_REGION_ADD;
62 region->user_vm_pa = user_gpa;
63 region->service_vm_pa = service_gpa;
64 region->size = size;
65 region->attr = ((mem_type & ACRN_MEM_TYPE_MASK) |
66 (mem_access_right & ACRN_MEM_ACCESS_RIGHT_MASK));
67 ret = modify_region(vm, region);
68
69 dev_dbg(acrn_dev.this_device,
70 "%s: user-GPA[%pK] service-GPA[%pK] size[0x%llx].\n",
71 __func__, (void *)user_gpa, (void *)service_gpa, size);
72 kfree(region);
73 return ret;
74 }
75
76 /**
77 * acrn_mm_region_del() - Del the EPT mapping of a memory region.
78 * @vm: User VM.
79 * @user_gpa: A GPA of the User VM.
80 * @size: Size of the region.
81 *
82 * Return: 0 on success, <0 for error.
83 */
acrn_mm_region_del(struct acrn_vm * vm,u64 user_gpa,u64 size)84 int acrn_mm_region_del(struct acrn_vm *vm, u64 user_gpa, u64 size)
85 {
86 struct vm_memory_region_op *region;
87 int ret = 0;
88
89 region = kzalloc(sizeof(*region), GFP_KERNEL);
90 if (!region)
91 return -ENOMEM;
92
93 region->type = ACRN_MEM_REGION_DEL;
94 region->user_vm_pa = user_gpa;
95 region->service_vm_pa = 0UL;
96 region->size = size;
97 region->attr = 0U;
98
99 ret = modify_region(vm, region);
100
101 dev_dbg(acrn_dev.this_device, "%s: user-GPA[%pK] size[0x%llx].\n",
102 __func__, (void *)user_gpa, size);
103 kfree(region);
104 return ret;
105 }
106
acrn_vm_memseg_map(struct acrn_vm * vm,struct acrn_vm_memmap * memmap)107 int acrn_vm_memseg_map(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
108 {
109 int ret;
110
111 if (memmap->type == ACRN_MEMMAP_RAM)
112 return acrn_vm_ram_map(vm, memmap);
113
114 if (memmap->type != ACRN_MEMMAP_MMIO) {
115 dev_dbg(acrn_dev.this_device,
116 "Invalid memmap type: %u\n", memmap->type);
117 return -EINVAL;
118 }
119
120 ret = acrn_mm_region_add(vm, memmap->user_vm_pa,
121 memmap->service_vm_pa, memmap->len,
122 ACRN_MEM_TYPE_UC, memmap->attr);
123 if (ret < 0)
124 dev_dbg(acrn_dev.this_device,
125 "Add memory region failed, VM[%u]!\n", vm->vmid);
126
127 return ret;
128 }
129
acrn_vm_memseg_unmap(struct acrn_vm * vm,struct acrn_vm_memmap * memmap)130 int acrn_vm_memseg_unmap(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
131 {
132 int ret;
133
134 if (memmap->type != ACRN_MEMMAP_MMIO) {
135 dev_dbg(acrn_dev.this_device,
136 "Invalid memmap type: %u\n", memmap->type);
137 return -EINVAL;
138 }
139
140 ret = acrn_mm_region_del(vm, memmap->user_vm_pa, memmap->len);
141 if (ret < 0)
142 dev_dbg(acrn_dev.this_device,
143 "Del memory region failed, VM[%u]!\n", vm->vmid);
144
145 return ret;
146 }
147
148 /**
149 * acrn_vm_ram_map() - Create a RAM EPT mapping of User VM.
150 * @vm: The User VM pointer
151 * @memmap: Info of the EPT mapping
152 *
153 * Return: 0 on success, <0 for error.
154 */
acrn_vm_ram_map(struct acrn_vm * vm,struct acrn_vm_memmap * memmap)155 int acrn_vm_ram_map(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
156 {
157 struct vm_memory_region_batch *regions_info;
158 int nr_pages, i, order, nr_regions = 0;
159 struct vm_memory_mapping *region_mapping;
160 struct vm_memory_region_op *vm_region;
161 struct page **pages = NULL, *page;
162 void *remap_vaddr;
163 int ret, pinned;
164 u64 user_vm_pa;
165 struct vm_area_struct *vma;
166
167 if (!vm || !memmap)
168 return -EINVAL;
169
170 /* Get the page number of the map region */
171 nr_pages = memmap->len >> PAGE_SHIFT;
172 if (!nr_pages)
173 return -EINVAL;
174
175 mmap_read_lock(current->mm);
176 vma = vma_lookup(current->mm, memmap->vma_base);
177 if (vma && ((vma->vm_flags & VM_PFNMAP) != 0)) {
178 unsigned long start_pfn, cur_pfn;
179 spinlock_t *ptl;
180 bool writable;
181 pte_t *ptep;
182
183 if ((memmap->vma_base + memmap->len) > vma->vm_end) {
184 mmap_read_unlock(current->mm);
185 return -EINVAL;
186 }
187
188 for (i = 0; i < nr_pages; i++) {
189 ret = follow_pte(vma->vm_mm,
190 memmap->vma_base + i * PAGE_SIZE,
191 &ptep, &ptl);
192 if (ret)
193 break;
194
195 cur_pfn = pte_pfn(ptep_get(ptep));
196 if (i == 0)
197 start_pfn = cur_pfn;
198 writable = !!pte_write(ptep_get(ptep));
199 pte_unmap_unlock(ptep, ptl);
200
201 /* Disallow write access if the PTE is not writable. */
202 if (!writable &&
203 (memmap->attr & ACRN_MEM_ACCESS_WRITE)) {
204 ret = -EFAULT;
205 break;
206 }
207
208 /* Disallow refcounted pages. */
209 if (pfn_valid(cur_pfn) &&
210 !PageReserved(pfn_to_page(cur_pfn))) {
211 ret = -EFAULT;
212 break;
213 }
214
215 /* Disallow non-contiguous ranges. */
216 if (cur_pfn != start_pfn + i) {
217 ret = -EINVAL;
218 break;
219 }
220 }
221 mmap_read_unlock(current->mm);
222
223 if (ret) {
224 dev_dbg(acrn_dev.this_device,
225 "Failed to lookup PFN at VMA:%pK.\n", (void *)memmap->vma_base);
226 return ret;
227 }
228
229 return acrn_mm_region_add(vm, memmap->user_vm_pa,
230 PFN_PHYS(start_pfn), memmap->len,
231 ACRN_MEM_TYPE_WB, memmap->attr);
232 }
233 mmap_read_unlock(current->mm);
234
235 pages = vzalloc(array_size(nr_pages, sizeof(*pages)));
236 if (!pages)
237 return -ENOMEM;
238
239 /* Lock the pages of user memory map region */
240 pinned = pin_user_pages_fast(memmap->vma_base,
241 nr_pages, FOLL_WRITE | FOLL_LONGTERM,
242 pages);
243 if (pinned < 0) {
244 ret = pinned;
245 goto free_pages;
246 } else if (pinned != nr_pages) {
247 ret = -EFAULT;
248 goto put_pages;
249 }
250
251 /* Create a kernel map for the map region */
252 remap_vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
253 if (!remap_vaddr) {
254 ret = -ENOMEM;
255 goto put_pages;
256 }
257
258 /* Record Service VM va <-> User VM pa mapping */
259 mutex_lock(&vm->regions_mapping_lock);
260 region_mapping = &vm->regions_mapping[vm->regions_mapping_count];
261 if (vm->regions_mapping_count < ACRN_MEM_MAPPING_MAX) {
262 region_mapping->pages = pages;
263 region_mapping->npages = nr_pages;
264 region_mapping->size = memmap->len;
265 region_mapping->service_vm_va = remap_vaddr;
266 region_mapping->user_vm_pa = memmap->user_vm_pa;
267 vm->regions_mapping_count++;
268 } else {
269 dev_warn(acrn_dev.this_device,
270 "Run out of memory mapping slots!\n");
271 ret = -ENOMEM;
272 mutex_unlock(&vm->regions_mapping_lock);
273 goto unmap_no_count;
274 }
275 mutex_unlock(&vm->regions_mapping_lock);
276
277 /* Calculate count of vm_memory_region_op */
278 for (i = 0; i < nr_pages; i += 1 << order) {
279 page = pages[i];
280 VM_BUG_ON_PAGE(PageTail(page), page);
281 order = compound_order(page);
282 nr_regions++;
283 }
284
285 /* Prepare the vm_memory_region_batch */
286 regions_info = kzalloc(struct_size(regions_info, regions_op,
287 nr_regions), GFP_KERNEL);
288 if (!regions_info) {
289 ret = -ENOMEM;
290 goto unmap_kernel_map;
291 }
292
293 /* Fill each vm_memory_region_op */
294 vm_region = regions_info->regions_op;
295 regions_info->vmid = vm->vmid;
296 regions_info->regions_num = nr_regions;
297 regions_info->regions_gpa = virt_to_phys(vm_region);
298 user_vm_pa = memmap->user_vm_pa;
299 for (i = 0; i < nr_pages; i += 1 << order) {
300 u32 region_size;
301
302 page = pages[i];
303 VM_BUG_ON_PAGE(PageTail(page), page);
304 order = compound_order(page);
305 region_size = PAGE_SIZE << order;
306 vm_region->type = ACRN_MEM_REGION_ADD;
307 vm_region->user_vm_pa = user_vm_pa;
308 vm_region->service_vm_pa = page_to_phys(page);
309 vm_region->size = region_size;
310 vm_region->attr = (ACRN_MEM_TYPE_WB & ACRN_MEM_TYPE_MASK) |
311 (memmap->attr & ACRN_MEM_ACCESS_RIGHT_MASK);
312
313 vm_region++;
314 user_vm_pa += region_size;
315 }
316
317 /* Inform the ACRN Hypervisor to set up EPT mappings */
318 ret = hcall_set_memory_regions(virt_to_phys(regions_info));
319 if (ret < 0) {
320 dev_dbg(acrn_dev.this_device,
321 "Failed to set regions, VM[%u]!\n", vm->vmid);
322 goto unset_region;
323 }
324 kfree(regions_info);
325
326 dev_dbg(acrn_dev.this_device,
327 "%s: VM[%u] service-GVA[%pK] user-GPA[%pK] size[0x%llx]\n",
328 __func__, vm->vmid,
329 remap_vaddr, (void *)memmap->user_vm_pa, memmap->len);
330 return ret;
331
332 unset_region:
333 kfree(regions_info);
334 unmap_kernel_map:
335 mutex_lock(&vm->regions_mapping_lock);
336 vm->regions_mapping_count--;
337 mutex_unlock(&vm->regions_mapping_lock);
338 unmap_no_count:
339 vunmap(remap_vaddr);
340 put_pages:
341 for (i = 0; i < pinned; i++)
342 unpin_user_page(pages[i]);
343 free_pages:
344 vfree(pages);
345 return ret;
346 }
347
348 /**
349 * acrn_vm_all_ram_unmap() - Destroy a RAM EPT mapping of User VM.
350 * @vm: The User VM
351 */
acrn_vm_all_ram_unmap(struct acrn_vm * vm)352 void acrn_vm_all_ram_unmap(struct acrn_vm *vm)
353 {
354 struct vm_memory_mapping *region_mapping;
355 int i, j;
356
357 mutex_lock(&vm->regions_mapping_lock);
358 for (i = 0; i < vm->regions_mapping_count; i++) {
359 region_mapping = &vm->regions_mapping[i];
360 vunmap(region_mapping->service_vm_va);
361 for (j = 0; j < region_mapping->npages; j++)
362 unpin_user_page(region_mapping->pages[j]);
363 vfree(region_mapping->pages);
364 }
365 mutex_unlock(&vm->regions_mapping_lock);
366 }
367