xref: /kernel/linux/linux-6.6/drivers/virt/acrn/mm.c (revision 62306a36)
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
18static 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 */
51int 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 */
84int 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
107int 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
130int 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 */
155int 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 = 0, 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	unsigned long pfn;
166	struct vm_area_struct *vma;
167
168	if (!vm || !memmap)
169		return -EINVAL;
170
171	mmap_read_lock(current->mm);
172	vma = vma_lookup(current->mm, memmap->vma_base);
173	if (vma && ((vma->vm_flags & VM_PFNMAP) != 0)) {
174		if ((memmap->vma_base + memmap->len) > vma->vm_end) {
175			mmap_read_unlock(current->mm);
176			return -EINVAL;
177		}
178
179		ret = follow_pfn(vma, memmap->vma_base, &pfn);
180		mmap_read_unlock(current->mm);
181		if (ret < 0) {
182			dev_dbg(acrn_dev.this_device,
183				"Failed to lookup PFN at VMA:%pK.\n", (void *)memmap->vma_base);
184			return ret;
185		}
186
187		return acrn_mm_region_add(vm, memmap->user_vm_pa,
188			 PFN_PHYS(pfn), memmap->len,
189			 ACRN_MEM_TYPE_WB, memmap->attr);
190	}
191	mmap_read_unlock(current->mm);
192
193	/* Get the page number of the map region */
194	nr_pages = memmap->len >> PAGE_SHIFT;
195	pages = vzalloc(array_size(nr_pages, sizeof(*pages)));
196	if (!pages)
197		return -ENOMEM;
198
199	/* Lock the pages of user memory map region */
200	pinned = pin_user_pages_fast(memmap->vma_base,
201				     nr_pages, FOLL_WRITE | FOLL_LONGTERM,
202				     pages);
203	if (pinned < 0) {
204		ret = pinned;
205		goto free_pages;
206	} else if (pinned != nr_pages) {
207		ret = -EFAULT;
208		goto put_pages;
209	}
210
211	/* Create a kernel map for the map region */
212	remap_vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
213	if (!remap_vaddr) {
214		ret = -ENOMEM;
215		goto put_pages;
216	}
217
218	/* Record Service VM va <-> User VM pa mapping */
219	mutex_lock(&vm->regions_mapping_lock);
220	region_mapping = &vm->regions_mapping[vm->regions_mapping_count];
221	if (vm->regions_mapping_count < ACRN_MEM_MAPPING_MAX) {
222		region_mapping->pages = pages;
223		region_mapping->npages = nr_pages;
224		region_mapping->size = memmap->len;
225		region_mapping->service_vm_va = remap_vaddr;
226		region_mapping->user_vm_pa = memmap->user_vm_pa;
227		vm->regions_mapping_count++;
228	} else {
229		dev_warn(acrn_dev.this_device,
230			"Run out of memory mapping slots!\n");
231		ret = -ENOMEM;
232		mutex_unlock(&vm->regions_mapping_lock);
233		goto unmap_no_count;
234	}
235	mutex_unlock(&vm->regions_mapping_lock);
236
237	/* Calculate count of vm_memory_region_op */
238	while (i < nr_pages) {
239		page = pages[i];
240		VM_BUG_ON_PAGE(PageTail(page), page);
241		order = compound_order(page);
242		nr_regions++;
243		i += 1 << order;
244	}
245
246	/* Prepare the vm_memory_region_batch */
247	regions_info = kzalloc(struct_size(regions_info, regions_op,
248					   nr_regions), GFP_KERNEL);
249	if (!regions_info) {
250		ret = -ENOMEM;
251		goto unmap_kernel_map;
252	}
253
254	/* Fill each vm_memory_region_op */
255	vm_region = regions_info->regions_op;
256	regions_info->vmid = vm->vmid;
257	regions_info->regions_num = nr_regions;
258	regions_info->regions_gpa = virt_to_phys(vm_region);
259	user_vm_pa = memmap->user_vm_pa;
260	i = 0;
261	while (i < nr_pages) {
262		u32 region_size;
263
264		page = pages[i];
265		VM_BUG_ON_PAGE(PageTail(page), page);
266		order = compound_order(page);
267		region_size = PAGE_SIZE << order;
268		vm_region->type = ACRN_MEM_REGION_ADD;
269		vm_region->user_vm_pa = user_vm_pa;
270		vm_region->service_vm_pa = page_to_phys(page);
271		vm_region->size = region_size;
272		vm_region->attr = (ACRN_MEM_TYPE_WB & ACRN_MEM_TYPE_MASK) |
273				  (memmap->attr & ACRN_MEM_ACCESS_RIGHT_MASK);
274
275		vm_region++;
276		user_vm_pa += region_size;
277		i += 1 << order;
278	}
279
280	/* Inform the ACRN Hypervisor to set up EPT mappings */
281	ret = hcall_set_memory_regions(virt_to_phys(regions_info));
282	if (ret < 0) {
283		dev_dbg(acrn_dev.this_device,
284			"Failed to set regions, VM[%u]!\n", vm->vmid);
285		goto unset_region;
286	}
287	kfree(regions_info);
288
289	dev_dbg(acrn_dev.this_device,
290		"%s: VM[%u] service-GVA[%pK] user-GPA[%pK] size[0x%llx]\n",
291		__func__, vm->vmid,
292		remap_vaddr, (void *)memmap->user_vm_pa, memmap->len);
293	return ret;
294
295unset_region:
296	kfree(regions_info);
297unmap_kernel_map:
298	mutex_lock(&vm->regions_mapping_lock);
299	vm->regions_mapping_count--;
300	mutex_unlock(&vm->regions_mapping_lock);
301unmap_no_count:
302	vunmap(remap_vaddr);
303put_pages:
304	for (i = 0; i < pinned; i++)
305		unpin_user_page(pages[i]);
306free_pages:
307	vfree(pages);
308	return ret;
309}
310
311/**
312 * acrn_vm_all_ram_unmap() - Destroy a RAM EPT mapping of User VM.
313 * @vm:	The User VM
314 */
315void acrn_vm_all_ram_unmap(struct acrn_vm *vm)
316{
317	struct vm_memory_mapping *region_mapping;
318	int i, j;
319
320	mutex_lock(&vm->regions_mapping_lock);
321	for (i = 0; i < vm->regions_mapping_count; i++) {
322		region_mapping = &vm->regions_mapping[i];
323		vunmap(region_mapping->service_vm_va);
324		for (j = 0; j < region_mapping->npages; j++)
325			unpin_user_page(region_mapping->pages[j]);
326		vfree(region_mapping->pages);
327	}
328	mutex_unlock(&vm->regions_mapping_lock);
329}
330