int acrn_vm_ram_map()

in acrn/mm.c [155:286]

• 111 lines of code
• 13 McCabe index (conditional complexity)

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 = 0, 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;

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

	/* Get the page number of the map region */
	nr_pages = memmap->len >> PAGE_SHIFT;
	pages = vzalloc(nr_pages * sizeof(struct page *));
	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 */
	while (i < nr_pages) {
		page = pages[i];
		VM_BUG_ON_PAGE(PageTail(page), page);
		order = compound_order(page);
		nr_regions++;
		i += 1 << order;
	}

	/* Prepare the vm_memory_region_batch */
	regions_info = kzalloc(sizeof(*regions_info) +
			       sizeof(*vm_region) * nr_regions,
			       GFP_KERNEL);
	if (!regions_info) {
		ret = -ENOMEM;
		goto unmap_kernel_map;
	}

	/* Fill each vm_memory_region_op */
	vm_region = (struct vm_memory_region_op *)(regions_info + 1);
	regions_info->vmid = vm->vmid;
	regions_info->regions_num = nr_regions;
	regions_info->regions_gpa = virt_to_phys(vm_region);
	user_vm_pa = memmap->user_vm_pa;
	i = 0;
	while (i < nr_pages) {
		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;
		i += 1 << order;
	}

	/* 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;
}