| // SPDX-License-Identifier: GPL-2.0 | |
| #include <linux/efi.h> | |
| #include <asm/efi.h> | |
| #include "efistub.h" | |
| /** | |
| * efi_allocate_pages_aligned() - Allocate memory pages | |
| * @size: minimum number of bytes to allocate | |
| * @addr: On return the address of the first allocated page. The first | |
| * allocated page has alignment EFI_ALLOC_ALIGN which is an | |
| * architecture dependent multiple of the page size. | |
| * @max: the address that the last allocated memory page shall not | |
| * exceed | |
| * @align: minimum alignment of the base of the allocation | |
| * @memory_type: the type of memory to allocate | |
| * | |
| * Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according | |
| * to @align, which should be >= EFI_ALLOC_ALIGN. The last allocated page will | |
| * not exceed the address given by @max. | |
| * | |
| * Return: status code | |
| */ | |
| efi_status_t efi_allocate_pages_aligned(unsigned long size, unsigned long *addr, | |
| unsigned long max, unsigned long align, | |
| int memory_type) | |
| { | |
| efi_physical_addr_t alloc_addr; | |
| efi_status_t status; | |
| int slack; | |
| max = min(max, EFI_ALLOC_LIMIT); | |
| if (align < EFI_ALLOC_ALIGN) | |
| align = EFI_ALLOC_ALIGN; | |
| alloc_addr = ALIGN_DOWN(max + 1, align) - 1; | |
| size = round_up(size, EFI_ALLOC_ALIGN); | |
| slack = align / EFI_PAGE_SIZE - 1; | |
| status = efi_bs_call(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS, | |
| memory_type, size / EFI_PAGE_SIZE + slack, | |
| &alloc_addr); | |
| if (status != EFI_SUCCESS) | |
| return status; | |
| *addr = ALIGN((unsigned long)alloc_addr, align); | |
| if (slack > 0) { | |
| int l = (alloc_addr & (align - 1)) / EFI_PAGE_SIZE; | |
| if (l) { | |
| efi_bs_call(free_pages, alloc_addr, slack - l + 1); | |
| slack = l - 1; | |
| } | |
| if (slack) | |
| efi_bs_call(free_pages, *addr + size, slack); | |
| } | |
| return EFI_SUCCESS; | |
| } |