// SPDX-License-Identifier: GPL-2.0
/*
* ACRN: Memory mapping management
*
* Copyright (C) 2020 Intel Corporation. All rights reserved.
*
* Authors:
* Fei Li <[email protected]>
* Shuo Liu <[email protected]>
*/
#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;
bool writable;
if ((memmap->vma_base + memmap->len) > vma->vm_end) {
mmap_read_unlock(current->mm);
return -EINVAL;
}
for (i = 0; i < nr_pages; i++) {
struct follow_pfnmap_args args = {
.vma = vma,
.address = memmap->vma_base + i * PAGE_SIZE,
};
ret = follow_pfnmap_start(&args);
if (ret)
break;
cur_pfn = args.pfn;
if (i == 0)
start_pfn = cur_pfn;
writable = args.writable;
follow_pfnmap_end(&args);
/* 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);
}
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