1f57db62cSArd Biesheuvel // SPDX-License-Identifier: GPL-2.0 2f57db62cSArd Biesheuvel 3f57db62cSArd Biesheuvel #include <linux/efi.h> 4f57db62cSArd Biesheuvel #include <asm/efi.h> 5f57db62cSArd Biesheuvel 6f57db62cSArd Biesheuvel #include "efistub.h" 7f57db62cSArd Biesheuvel 81d9b1768SHeinrich Schuchardt /** 91d9b1768SHeinrich Schuchardt * efi_get_memory_map() - get memory map 10eab31265SArd Biesheuvel * @map: pointer to memory map pointer to which to assign the 11eab31265SArd Biesheuvel * newly allocated memory map 12171539f5SArd Biesheuvel * @install_cfg_tbl: whether or not to install the boot memory map as a 13171539f5SArd Biesheuvel * configuration table 141d9b1768SHeinrich Schuchardt * 151d9b1768SHeinrich Schuchardt * Retrieve the UEFI memory map. The allocated memory leaves room for 161d9b1768SHeinrich Schuchardt * up to EFI_MMAP_NR_SLACK_SLOTS additional memory map entries. 171d9b1768SHeinrich Schuchardt * 181d9b1768SHeinrich Schuchardt * Return: status code 191d9b1768SHeinrich Schuchardt */ 20171539f5SArd Biesheuvel efi_status_t efi_get_memory_map(struct efi_boot_memmap **map, 21171539f5SArd Biesheuvel bool install_cfg_tbl) 22f57db62cSArd Biesheuvel { 23171539f5SArd Biesheuvel int memtype = install_cfg_tbl ? EFI_ACPI_RECLAIM_MEMORY 24171539f5SArd Biesheuvel : EFI_LOADER_DATA; 25171539f5SArd Biesheuvel efi_guid_t tbl_guid = LINUX_EFI_BOOT_MEMMAP_GUID; 26eab31265SArd Biesheuvel struct efi_boot_memmap *m, tmp; 27f57db62cSArd Biesheuvel efi_status_t status; 28eab31265SArd Biesheuvel unsigned long size; 29f57db62cSArd Biesheuvel 30eab31265SArd Biesheuvel tmp.map_size = 0; 31eab31265SArd Biesheuvel status = efi_bs_call(get_memory_map, &tmp.map_size, NULL, &tmp.map_key, 32eab31265SArd Biesheuvel &tmp.desc_size, &tmp.desc_ver); 33eab31265SArd Biesheuvel if (status != EFI_BUFFER_TOO_SMALL) 34eab31265SArd Biesheuvel return EFI_LOAD_ERROR; 35eab31265SArd Biesheuvel 36eab31265SArd Biesheuvel size = tmp.map_size + tmp.desc_size * EFI_MMAP_NR_SLACK_SLOTS; 37171539f5SArd Biesheuvel status = efi_bs_call(allocate_pool, memtype, sizeof(*m) + size, 38eab31265SArd Biesheuvel (void **)&m); 39f57db62cSArd Biesheuvel if (status != EFI_SUCCESS) 40eab31265SArd Biesheuvel return status; 41f57db62cSArd Biesheuvel 42171539f5SArd Biesheuvel if (install_cfg_tbl) { 43171539f5SArd Biesheuvel /* 44171539f5SArd Biesheuvel * Installing a configuration table might allocate memory, and 45171539f5SArd Biesheuvel * this may modify the memory map. This means we should install 46171539f5SArd Biesheuvel * the configuration table first, and re-install or delete it 47171539f5SArd Biesheuvel * as needed. 48171539f5SArd Biesheuvel */ 49171539f5SArd Biesheuvel status = efi_bs_call(install_configuration_table, &tbl_guid, m); 50171539f5SArd Biesheuvel if (status != EFI_SUCCESS) 51171539f5SArd Biesheuvel goto free_map; 52171539f5SArd Biesheuvel } 53171539f5SArd Biesheuvel 54eab31265SArd Biesheuvel m->buff_size = m->map_size = size; 55eab31265SArd Biesheuvel status = efi_bs_call(get_memory_map, &m->map_size, m->map, &m->map_key, 56eab31265SArd Biesheuvel &m->desc_size, &m->desc_ver); 57eab31265SArd Biesheuvel if (status != EFI_SUCCESS) 58171539f5SArd Biesheuvel goto uninstall_table; 59eab31265SArd Biesheuvel 60eab31265SArd Biesheuvel *map = m; 61eab31265SArd Biesheuvel return EFI_SUCCESS; 62eab31265SArd Biesheuvel 63171539f5SArd Biesheuvel uninstall_table: 64171539f5SArd Biesheuvel if (install_cfg_tbl) 65171539f5SArd Biesheuvel efi_bs_call(install_configuration_table, &tbl_guid, NULL); 66eab31265SArd Biesheuvel free_map: 67f57db62cSArd Biesheuvel efi_bs_call(free_pool, m); 68f57db62cSArd Biesheuvel return status; 69f57db62cSArd Biesheuvel } 70f57db62cSArd Biesheuvel 71eaa6fc67SHeinrich Schuchardt /** 72eaa6fc67SHeinrich Schuchardt * efi_allocate_pages() - Allocate memory pages 73eaa6fc67SHeinrich Schuchardt * @size: minimum number of bytes to allocate 74eaa6fc67SHeinrich Schuchardt * @addr: On return the address of the first allocated page. The first 75eaa6fc67SHeinrich Schuchardt * allocated page has alignment EFI_ALLOC_ALIGN which is an 76eaa6fc67SHeinrich Schuchardt * architecture dependent multiple of the page size. 77eaa6fc67SHeinrich Schuchardt * @max: the address that the last allocated memory page shall not 78eaa6fc67SHeinrich Schuchardt * exceed 79eaa6fc67SHeinrich Schuchardt * 80eaa6fc67SHeinrich Schuchardt * Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according 81eaa6fc67SHeinrich Schuchardt * to EFI_ALLOC_ALIGN. The last allocated page will not exceed the address 82eaa6fc67SHeinrich Schuchardt * given by @max. 83eaa6fc67SHeinrich Schuchardt * 84eaa6fc67SHeinrich Schuchardt * Return: status code 85f57db62cSArd Biesheuvel */ 86a7495c28SArd Biesheuvel efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr, 87a7495c28SArd Biesheuvel unsigned long max) 88f57db62cSArd Biesheuvel { 8943b1df0eSArd Biesheuvel efi_physical_addr_t alloc_addr; 90f57db62cSArd Biesheuvel efi_status_t status; 91f57db62cSArd Biesheuvel 9243b1df0eSArd Biesheuvel if (EFI_ALLOC_ALIGN > EFI_PAGE_SIZE) 9343b1df0eSArd Biesheuvel return efi_allocate_pages_aligned(size, addr, max, 94*9cf42bcaSArd Biesheuvel EFI_ALLOC_ALIGN, 95*9cf42bcaSArd Biesheuvel EFI_LOADER_DATA); 9643b1df0eSArd Biesheuvel 9743b1df0eSArd Biesheuvel alloc_addr = ALIGN_DOWN(max + 1, EFI_ALLOC_ALIGN) - 1; 98a7495c28SArd Biesheuvel status = efi_bs_call(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS, 9943b1df0eSArd Biesheuvel EFI_LOADER_DATA, DIV_ROUND_UP(size, EFI_PAGE_SIZE), 100a7495c28SArd Biesheuvel &alloc_addr); 101a7495c28SArd Biesheuvel if (status != EFI_SUCCESS) 102f57db62cSArd Biesheuvel return status; 103f57db62cSArd Biesheuvel 10443b1df0eSArd Biesheuvel *addr = alloc_addr; 105a7495c28SArd Biesheuvel return EFI_SUCCESS; 106a7495c28SArd Biesheuvel } 10743b1df0eSArd Biesheuvel 1081d9b1768SHeinrich Schuchardt /** 1091d9b1768SHeinrich Schuchardt * efi_free() - free memory pages 1101d9b1768SHeinrich Schuchardt * @size: size of the memory area to free in bytes 1111d9b1768SHeinrich Schuchardt * @addr: start of the memory area to free (must be EFI_PAGE_SIZE 1121d9b1768SHeinrich Schuchardt * aligned) 1131d9b1768SHeinrich Schuchardt * 1141d9b1768SHeinrich Schuchardt * @size is rounded up to a multiple of EFI_ALLOC_ALIGN which is an 1151d9b1768SHeinrich Schuchardt * architecture specific multiple of EFI_PAGE_SIZE. So this function should 1161d9b1768SHeinrich Schuchardt * only be used to return pages allocated with efi_allocate_pages() or 1171d9b1768SHeinrich Schuchardt * efi_low_alloc_above(). 1181d9b1768SHeinrich Schuchardt */ 119f57db62cSArd Biesheuvel void efi_free(unsigned long size, unsigned long addr) 120f57db62cSArd Biesheuvel { 121f57db62cSArd Biesheuvel unsigned long nr_pages; 122f57db62cSArd Biesheuvel 123f57db62cSArd Biesheuvel if (!size) 124f57db62cSArd Biesheuvel return; 125f57db62cSArd Biesheuvel 126f57db62cSArd Biesheuvel nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE; 127f57db62cSArd Biesheuvel efi_bs_call(free_pages, addr, nr_pages); 128f57db62cSArd Biesheuvel } 129