summaryrefslogtreecommitdiff
path: root/drivers/virt/acrn/mm.c
blob: db8ff1d0ac23ce7630ac0623eb70be0f6dff19e4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
// SPDX-License-Identifier: GPL-2.0
/*
 * ACRN: Memory mapping management
 *
 * Copyright (C) 2020 Intel Corporation. All rights reserved.
 *
 * Authors:
 *	Fei Li <lei1.li@intel.com>
 *	Shuo Liu <shuo.a.liu@intel.com>
 */

#include <linux/io.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>

#include "acrn_drv.h"

static int modify_region(struct acrn_vm *vm, struct vm_memory_region_op *region)
{
	struct vm_memory_region_batch *regions;
	int ret;

	regions = kzalloc(sizeof(*regions), GFP_KERNEL);
	if (!regions)
		return -ENOMEM;

	regions->vmid = vm->vmid;
	regions->regions_num = 1;
	regions->regions_gpa = virt_to_phys(region);

	ret = hcall_set_memory_regions(virt_to_phys(regions));
	if (ret < 0)
		dev_dbg(acrn_dev.this_device,
			"Failed to set memory region for VM[%u]!\n", vm->vmid);

	kfree(regions);
	return ret;
}

/**
 * acrn_mm_region_add() - Set up the EPT mapping of a memory region.
 * @vm:			User VM.
 * @user_gpa:		A GPA of User VM.
 * @service_gpa:	A GPA of Service VM.
 * @size:		Size of the region.
 * @mem_type:		Combination of ACRN_MEM_TYPE_*.
 * @mem_access_right:	Combination of ACRN_MEM_ACCESS_*.
 *
 * Return: 0 on success, <0 on error.
 */
int acrn_mm_region_add(struct acrn_vm *vm, u64 user_gpa, u64 service_gpa,
		       u64 size, u32 mem_type, u32 mem_access_right)
{
	struct vm_memory_region_op *region;
	int ret = 0;

	region = kzalloc(sizeof(*region), GFP_KERNEL);
	if (!region)
		return -ENOMEM;

	region->type = ACRN_MEM_REGION_ADD;
	region->user_vm_pa = user_gpa;
	region->service_vm_pa = service_gpa;
	region->size = size;
	region->attr = ((mem_type & ACRN_MEM_TYPE_MASK) |
			(mem_access_right & ACRN_MEM_ACCESS_RIGHT_MASK));
	ret = modify_region(vm, region);

	dev_dbg(acrn_dev.this_device,
		"%s: user-GPA[%pK] service-GPA[%pK] size[0x%llx].\n",
		__func__, (void *)user_gpa, (void *)service_gpa, size);
	kfree(region);
	return ret;
}

/**
 * acrn_mm_region_del() - Del the EPT mapping of a memory region.
 * @vm:		User VM.
 * @user_gpa:	A GPA of the User VM.
 * @size:	Size of the region.
 *
 * Return: 0 on success, <0 for error.
 */
int acrn_mm_region_del(struct acrn_vm *vm, u64 user_gpa, u64 size)
{
	struct vm_memory_region_op *region;
	int ret = 0;

	region = kzalloc(sizeof(*region), GFP_KERNEL);
	if (!region)
		return -ENOMEM;

	region->type = ACRN_MEM_REGION_DEL;
	region->user_vm_pa = user_gpa;
	region->service_vm_pa = 0UL;
	region->size = size;
	region->attr = 0U;

	ret = modify_region(vm, region);

	dev_dbg(acrn_dev.this_device, "%s: user-GPA[%pK] size[0x%llx].\n",
		__func__, (void *)user_gpa, size);
	kfree(region);
	return ret;
}

int acrn_vm_memseg_map(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
{
	int ret;

	if (memmap->type == ACRN_MEMMAP_RAM)
		return acrn_vm_ram_map(vm, memmap);

	if (memmap->type != ACRN_MEMMAP_MMIO) {
		dev_dbg(acrn_dev.this_device,
			"Invalid memmap type: %u\n", memmap->type);
		return -EINVAL;
	}

	ret = acrn_mm_region_add(vm, memmap->user_vm_pa,
				 memmap->service_vm_pa, memmap->len,
				 ACRN_MEM_TYPE_UC, memmap->attr);
	if (ret < 0)
		dev_dbg(acrn_dev.this_device,
			"Add memory region failed, VM[%u]!\n", vm->vmid);

	return ret;
}

int acrn_vm_memseg_unmap(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
{
	int ret;

	if (memmap->type != ACRN_MEMMAP_MMIO) {
		dev_dbg(acrn_dev.this_device,
			"Invalid memmap type: %u\n", memmap->type);
		return -EINVAL;
	}

	ret = acrn_mm_region_del(vm, memmap->user_vm_pa, memmap->len);
	if (ret < 0)
		dev_dbg(acrn_dev.this_device,
			"Del memory region failed, VM[%u]!\n", vm->vmid);

	return ret;
}

/**
 * acrn_vm_ram_map() - Create a RAM EPT mapping of User VM.
 * @vm:		The User VM pointer
 * @memmap:	Info of the EPT mapping
 *
 * Return: 0 on success, <0 for error.
 */
int acrn_vm_ram_map(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
{
	struct vm_memory_region_batch *regions_info;
	int nr_pages, i, order, nr_regions = 0;
	struct vm_memory_mapping *region_mapping;
	struct vm_memory_region_op *vm_region;
	struct page **pages = NULL, *page;
	void *remap_vaddr;
	int ret, pinned;
	u64 user_vm_pa;
	struct vm_area_struct *vma;

	if (!vm || !memmap)
		return -EINVAL;

	/* Get the page number of the map region */
	nr_pages = memmap->len >> PAGE_SHIFT;
	if (!nr_pages)
		return -EINVAL;

	mmap_read_lock(current->mm);
	vma = vma_lookup(current->mm, memmap->vma_base);
	if (vma && ((vma->vm_flags & VM_PFNMAP) != 0)) {
		unsigned long start_pfn, cur_pfn;
		spinlock_t *ptl;
		bool writable;
		pte_t *ptep;

		if ((memmap->vma_base + memmap->len) > vma->vm_end) {
			mmap_read_unlock(current->mm);
			return -EINVAL;
		}

		for (i = 0; i < nr_pages; i++) {
			ret = follow_pte(vma, memmap->vma_base + i * PAGE_SIZE,
					 &ptep, &ptl);
			if (ret)
				break;

			cur_pfn = pte_pfn(ptep_get(ptep));
			if (i == 0)
				start_pfn = cur_pfn;
			writable = !!pte_write(ptep_get(ptep));
			pte_unmap_unlock(ptep, ptl);

			/* Disallow write access if the PTE is not writable. */
			if (!writable &&
			    (memmap->attr & ACRN_MEM_ACCESS_WRITE)) {
				ret = -EFAULT;
				break;
			}

			/* Disallow refcounted pages. */
			if (pfn_valid(cur_pfn) &&
			    !PageReserved(pfn_to_page(cur_pfn))) {
				ret = -EFAULT;
				break;
			}

			/* Disallow non-contiguous ranges. */
			if (cur_pfn != start_pfn + i) {
				ret = -EINVAL;
				break;
			}
		}
		mmap_read_unlock(current->mm);

		if (ret) {
			dev_dbg(acrn_dev.this_device,
				"Failed to lookup PFN at VMA:%pK.\n", (void *)memmap->vma_base);
			return ret;
		}

		return acrn_mm_region_add(vm, memmap->user_vm_pa,
			 PFN_PHYS(start_pfn), memmap->len,
			 ACRN_MEM_TYPE_WB, memmap->attr);
	}
	mmap_read_unlock(current->mm);

	pages = vzalloc(array_size(nr_pages, sizeof(*pages)));
	if (!pages)
		return -ENOMEM;

	/* Lock the pages of user memory map region */
	pinned = pin_user_pages_fast(memmap->vma_base,
				     nr_pages, FOLL_WRITE | FOLL_LONGTERM,
				     pages);
	if (pinned < 0) {
		ret = pinned;
		goto free_pages;
	} else if (pinned != nr_pages) {
		ret = -EFAULT;
		goto put_pages;
	}

	/* Create a kernel map for the map region */
	remap_vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
	if (!remap_vaddr) {
		ret = -ENOMEM;
		goto put_pages;
	}

	/* Record Service VM va <-> User VM pa mapping */
	mutex_lock(&vm->regions_mapping_lock);
	region_mapping = &vm->regions_mapping[vm->regions_mapping_count];
	if (vm->regions_mapping_count < ACRN_MEM_MAPPING_MAX) {
		region_mapping->pages = pages;
		region_mapping->npages = nr_pages;
		region_mapping->size = memmap->len;
		region_mapping->service_vm_va = remap_vaddr;
		region_mapping->user_vm_pa = memmap->user_vm_pa;
		vm->regions_mapping_count++;
	} else {
		dev_warn(acrn_dev.this_device,
			"Run out of memory mapping slots!\n");
		ret = -ENOMEM;
		mutex_unlock(&vm->regions_mapping_lock);
		goto unmap_no_count;
	}
	mutex_unlock(&vm->regions_mapping_lock);

	/* Calculate count of vm_memory_region_op */
	for (i = 0; i < nr_pages; i += 1 << order) {
		page = pages[i];
		VM_BUG_ON_PAGE(PageTail(page), page);
		order = compound_order(page);
		nr_regions++;
	}

	/* Prepare the vm_memory_region_batch */
	regions_info = kzalloc(struct_size(regions_info, regions_op,
					   nr_regions), GFP_KERNEL);
	if (!regions_info) {
		ret = -ENOMEM;
		goto unmap_kernel_map;
	}
	regions_info->regions_num = nr_regions;

	/* Fill each vm_memory_region_op */
	vm_region = regions_info->regions_op;
	regions_info->vmid = vm->vmid;
	regions_info->regions_gpa = virt_to_phys(vm_region);
	user_vm_pa = memmap->user_vm_pa;
	for (i = 0; i < nr_pages; i += 1 << order) {
		u32 region_size;

		page = pages[i];
		VM_BUG_ON_PAGE(PageTail(page), page);
		order = compound_order(page);
		region_size = PAGE_SIZE << order;
		vm_region->type = ACRN_MEM_REGION_ADD;
		vm_region->user_vm_pa = user_vm_pa;
		vm_region->service_vm_pa = page_to_phys(page);
		vm_region->size = region_size;
		vm_region->attr = (ACRN_MEM_TYPE_WB & ACRN_MEM_TYPE_MASK) |
				  (memmap->attr & ACRN_MEM_ACCESS_RIGHT_MASK);

		vm_region++;
		user_vm_pa += region_size;
	}

	/* Inform the ACRN Hypervisor to set up EPT mappings */
	ret = hcall_set_memory_regions(virt_to_phys(regions_info));
	if (ret < 0) {
		dev_dbg(acrn_dev.this_device,
			"Failed to set regions, VM[%u]!\n", vm->vmid);
		goto unset_region;
	}
	kfree(regions_info);

	dev_dbg(acrn_dev.this_device,
		"%s: VM[%u] service-GVA[%pK] user-GPA[%pK] size[0x%llx]\n",
		__func__, vm->vmid,
		remap_vaddr, (void *)memmap->user_vm_pa, memmap->len);
	return ret;

unset_region:
	kfree(regions_info);
unmap_kernel_map:
	mutex_lock(&vm->regions_mapping_lock);
	vm->regions_mapping_count--;
	mutex_unlock(&vm->regions_mapping_lock);
unmap_no_count:
	vunmap(remap_vaddr);
put_pages:
	for (i = 0; i < pinned; i++)
		unpin_user_page(pages[i]);
free_pages:
	vfree(pages);
	return ret;
}

/**
 * acrn_vm_all_ram_unmap() - Destroy a RAM EPT mapping of User VM.
 * @vm:	The User VM
 */
void acrn_vm_all_ram_unmap(struct acrn_vm *vm)
{
	struct vm_memory_mapping *region_mapping;
	int i, j;

	mutex_lock(&vm->regions_mapping_lock);
	for (i = 0; i < vm->regions_mapping_count; i++) {
		region_mapping = &vm->regions_mapping[i];
		vunmap(region_mapping->service_vm_va);
		for (j = 0; j < region_mapping->npages; j++)
			unpin_user_page(region_mapping->pages[j]);
		vfree(region_mapping->pages);
	}
	mutex_unlock(&vm->regions_mapping_lock);
}