// 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 * * 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) { efi_physical_addr_t alloc_addr; efi_status_t status; int slack; 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, EFI_LOADER_DATA, 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; }