linux/drivers/firmware/efi/libstub/mem.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/efi.h>
#include <asm/efi.h>

#include "efistub.h"

/**
 * efi_get_memory_map() - get memory map
 * @map:		pointer to memory map pointer to which to assign the
 *			newly allocated memory map
 * @install_cfg_tbl:	whether or not to install the boot memory map as a
 *			configuration table
 *
 * Retrieve the UEFI memory map. The allocated memory leaves room for
 * up to EFI_MMAP_NR_SLACK_SLOTS additional memory map entries.
 *
 * Return:	status code
 */
efi_status_t efi_get_memory_map(struct efi_boot_memmap **map,
				bool install_cfg_tbl)
{ … }

/**
 * efi_allocate_pages() - 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
 *
 * Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according
 * to EFI_ALLOC_ALIGN. The last allocated page will not exceed the address
 * given by @max.
 *
 * Return:	status code
 */
efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr,
				unsigned long max)
{ … }

/**
 * efi_free() - free memory pages
 * @size:	size of the memory area to free in bytes
 * @addr:	start of the memory area to free (must be EFI_PAGE_SIZE
 *		aligned)
 *
 * @size is rounded up to a multiple of EFI_ALLOC_ALIGN which is an
 * architecture specific multiple of EFI_PAGE_SIZE. So this function should
 * only be used to return pages allocated with efi_allocate_pages() or
 * efi_low_alloc_above().
 */
void efi_free(unsigned long size, unsigned long addr)
{ … }