1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/efi.h> 4 #include <asm/efi.h> 5 6 #include "efistub.h" 7 8 /** 9 * efi_allocate_pages_aligned() - Allocate memory pages 10 * @size: minimum number of bytes to allocate 11 * @addr: On return the address of the first allocated page. The first 12 * allocated page has alignment EFI_ALLOC_ALIGN which is an 13 * architecture dependent multiple of the page size. 14 * @max: the address that the last allocated memory page shall not 15 * exceed 16 * @align: minimum alignment of the base of the allocation 17 * @memory_type: the type of memory to allocate 18 * 19 * Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according 20 * to @align, which should be >= EFI_ALLOC_ALIGN. The last allocated page will 21 * not exceed the address given by @max. 22 * 23 * Return: status code 24 */ 25 efi_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