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1// SPDX-License-Identifier: GPL-2.02 3#include <linux/efi.h>4#include <asm/efi.h>5 6#include "efistub.h"7 8/**9 * efi_allocate_pages_aligned() - Allocate memory pages10 * @size: minimum number of bytes to allocate11 * @addr: On return the address of the first allocated page. The first12 * allocated page has alignment EFI_ALLOC_ALIGN which is an13 * architecture dependent multiple of the page size.14 * @max: the address that the last allocated memory page shall not15 * exceed16 * @align: minimum alignment of the base of the allocation17 * @memory_type: the type of memory to allocate18 *19 * Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according20 * to @align, which should be >= EFI_ALLOC_ALIGN. The last allocated page will21 * not exceed the address given by @max.22 *23 * Return: status code24 */25efi_status_t efi_allocate_pages_aligned(unsigned long size, unsigned long *addr,26 unsigned long max, unsigned long align,27 int memory_type)28{29 efi_physical_addr_t alloc_addr;30 efi_status_t status;31 int slack;32 33 max = min(max, EFI_ALLOC_LIMIT);34 35 if (align < EFI_ALLOC_ALIGN)36 align = EFI_ALLOC_ALIGN;37 38 alloc_addr = ALIGN_DOWN(max + 1, align) - 1;39 size = round_up(size, EFI_ALLOC_ALIGN);40 slack = align / EFI_PAGE_SIZE - 1;41 42 status = efi_bs_call(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS,43 memory_type, size / EFI_PAGE_SIZE + slack,44 &alloc_addr);45 if (status != EFI_SUCCESS)46 return status;47 48 *addr = ALIGN((unsigned long)alloc_addr, align);49 50 if (slack > 0) {51 int l = (alloc_addr & (align - 1)) / EFI_PAGE_SIZE;52 53 if (l) {54 efi_bs_call(free_pages, alloc_addr, slack - l + 1);55 slack = l - 1;56 }57 if (slack)58 efi_bs_call(free_pages, *addr + size, slack);59 }60 return EFI_SUCCESS;61}62