diff options
Diffstat (limited to 'drivers/firmware/efi/efi-stub-helper.c')
| -rw-r--r-- | drivers/firmware/efi/efi-stub-helper.c | 636 |
1 files changed, 636 insertions, 0 deletions
diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c new file mode 100644 index 000000000000..b6bffbfd3be7 --- /dev/null +++ b/drivers/firmware/efi/efi-stub-helper.c @@ -0,0 +1,636 @@ +/* + * Helper functions used by the EFI stub on multiple + * architectures. This should be #included by the EFI stub + * implementation files. + * + * Copyright 2011 Intel Corporation; author Matt Fleming + * + * This file is part of the Linux kernel, and is made available + * under the terms of the GNU General Public License version 2. + * + */ +#define EFI_READ_CHUNK_SIZE (1024 * 1024) + +struct file_info { + efi_file_handle_t *handle; + u64 size; +}; + + + + +static void efi_char16_printk(efi_system_table_t *sys_table_arg, + efi_char16_t *str) +{ + struct efi_simple_text_output_protocol *out; + + out = (struct efi_simple_text_output_protocol *)sys_table_arg->con_out; + efi_call_phys2(out->output_string, out, str); +} + +static void efi_printk(efi_system_table_t *sys_table_arg, char *str) +{ + char *s8; + + for (s8 = str; *s8; s8++) { + efi_char16_t ch[2] = { 0 }; + + ch[0] = *s8; + if (*s8 == '\n') { + efi_char16_t nl[2] = { '\r', 0 }; + efi_char16_printk(sys_table_arg, nl); + } + + efi_char16_printk(sys_table_arg, ch); + } +} + + +static efi_status_t efi_get_memory_map(efi_system_table_t *sys_table_arg, + efi_memory_desc_t **map, + unsigned long *map_size, + unsigned long *desc_size, + u32 *desc_ver, + unsigned long *key_ptr) +{ + efi_memory_desc_t *m = NULL; + efi_status_t status; + unsigned long key; + u32 desc_version; + + *map_size = sizeof(*m) * 32; +again: + /* + * Add an additional efi_memory_desc_t because we're doing an + * allocation which may be in a new descriptor region. + */ + *map_size += sizeof(*m); + status = efi_call_phys3(sys_table_arg->boottime->allocate_pool, + EFI_LOADER_DATA, *map_size, (void **)&m); + if (status != EFI_SUCCESS) + goto fail; + + status = efi_call_phys5(sys_table_arg->boottime->get_memory_map, + map_size, m, &key, desc_size, &desc_version); + if (status == EFI_BUFFER_TOO_SMALL) { + efi_call_phys1(sys_table_arg->boottime->free_pool, m); + goto again; + } + + if (status != EFI_SUCCESS) + efi_call_phys1(sys_table_arg->boottime->free_pool, m); + if (key_ptr && status == EFI_SUCCESS) + *key_ptr = key; + if (desc_ver && status == EFI_SUCCESS) + *desc_ver = desc_version; + +fail: + *map = m; + return status; +} + +/* + * Allocate at the highest possible address that is not above 'max'. + */ +static efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg, + unsigned long size, unsigned long align, + unsigned long *addr, unsigned long max) +{ + unsigned long map_size, desc_size; + efi_memory_desc_t *map; + efi_status_t status; + unsigned long nr_pages; + u64 max_addr = 0; + int i; + + status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size, + NULL, NULL); + if (status != EFI_SUCCESS) + goto fail; + + /* + * Enforce minimum alignment that EFI requires when requesting + * a specific address. We are doing page-based allocations, + * so we must be aligned to a page. + */ + if (align < EFI_PAGE_SIZE) + align = EFI_PAGE_SIZE; + + nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; +again: + for (i = 0; i < map_size / desc_size; i++) { + efi_memory_desc_t *desc; + unsigned long m = (unsigned long)map; + u64 start, end; + + desc = (efi_memory_desc_t *)(m + (i * desc_size)); + if (desc->type != EFI_CONVENTIONAL_MEMORY) + continue; + + if (desc->num_pages < nr_pages) + continue; + + start = desc->phys_addr; + end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT); + + if ((start + size) > end || (start + size) > max) + continue; + + if (end - size > max) + end = max; + + if (round_down(end - size, align) < start) + continue; + + start = round_down(end - size, align); + + /* + * Don't allocate at 0x0. It will confuse code that + * checks pointers against NULL. + */ + if (start == 0x0) + continue; + + if (start > max_addr) + max_addr = start; + } + + if (!max_addr) + status = EFI_NOT_FOUND; + else { + status = efi_call_phys4(sys_table_arg->boottime->allocate_pages, + EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA, + nr_pages, &max_addr); + if (status != EFI_SUCCESS) { + max = max_addr; + max_addr = 0; + goto again; + } + + *addr = max_addr; + } + + efi_call_phys1(sys_table_arg->boottime->free_pool, map); + +fail: + return status; +} + +/* + * Allocate at the lowest possible address. + */ +static efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg, + unsigned long size, unsigned long align, + unsigned long *addr) +{ + unsigned long map_size, desc_size; + efi_memory_desc_t *map; + efi_status_t status; + unsigned long nr_pages; + int i; + + status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size, + NULL, NULL); + if (status != EFI_SUCCESS) + goto fail; + + /* + * Enforce minimum alignment that EFI requires when requesting + * a specific address. We are doing page-based allocations, + * so we must be aligned to a page. + */ + if (align < EFI_PAGE_SIZE) + align = EFI_PAGE_SIZE; + + nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; + for (i = 0; i < map_size / desc_size; i++) { + efi_memory_desc_t *desc; + unsigned long m = (unsigned long)map; + u64 start, end; + + desc = (efi_memory_desc_t *)(m + (i * desc_size)); + + if (desc->type != EFI_CONVENTIONAL_MEMORY) + continue; + + if (desc->num_pages < nr_pages) + continue; + + start = desc->phys_addr; + end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT); + + /* + * Don't allocate at 0x0. It will confuse code that + * checks pointers against NULL. Skip the first 8 + * bytes so we start at a nice even number. + */ + if (start == 0x0) + start += 8; + + start = round_up(start, align); + if ((start + size) > end) + continue; + + status = efi_call_phys4(sys_table_arg->boottime->allocate_pages, + EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA, + nr_pages, &start); + if (status == EFI_SUCCESS) { + *addr = start; + break; + } + } + + if (i == map_size / desc_size) + status = EFI_NOT_FOUND; + + efi_call_phys1(sys_table_arg->boottime->free_pool, map); +fail: + return status; +} + +static void efi_free(efi_system_table_t *sys_table_arg, unsigned long size, + unsigned long addr) +{ + unsigned long nr_pages; + + if (!size) + return; + + nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; + efi_call_phys2(sys_table_arg->boottime->free_pages, addr, nr_pages); +} + + +/* + * Check the cmdline for a LILO-style file= arguments. + * + * We only support loading a file from the same filesystem as + * the kernel image. + */ +static efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg, + efi_loaded_image_t *image, + char *cmd_line, char *option_string, + unsigned long max_addr, + unsigned long *load_addr, + unsigned long *load_size) +{ + struct file_info *files; + unsigned long file_addr; + efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID; + u64 file_size_total; + efi_file_io_interface_t *io; + efi_file_handle_t *fh; + efi_status_t status; + int nr_files; + char *str; + int i, j, k; + + file_addr = 0; + file_size_total = 0; + + str = cmd_line; + + j = 0; /* See close_handles */ + + if (!load_addr || !load_size) + return EFI_INVALID_PARAMETER; + + *load_addr = 0; + *load_size = 0; + + if (!str || !*str) + return EFI_SUCCESS; + + for (nr_files = 0; *str; nr_files++) { + str = strstr(str, option_string); + if (!str) + break; + + str += strlen(option_string); + + /* Skip any leading slashes */ + while (*str == '/' || *str == '\\') + str++; + + while (*str && *str != ' ' && *str != '\n') + str++; + } + + if (!nr_files) + return EFI_SUCCESS; + + status = efi_call_phys3(sys_table_arg->boottime->allocate_pool, + EFI_LOADER_DATA, + nr_files * sizeof(*files), + (void **)&files); + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to alloc mem for file handle list\n"); + goto fail; + } + + str = cmd_line; + for (i = 0; i < nr_files; i++) { + struct file_info *file; + efi_file_handle_t *h; + efi_file_info_t *info; + efi_char16_t filename_16[256]; + unsigned long info_sz; + efi_guid_t info_guid = EFI_FILE_INFO_ID; + efi_char16_t *p; + u64 file_sz; + + str = strstr(str, option_string); + if (!str) + break; + + str += strlen(option_string); + + file = &files[i]; + p = filename_16; + + /* Skip any leading slashes */ + while (*str == '/' || *str == '\\') + str++; + + while (*str && *str != ' ' && *str != '\n') { + if ((u8 *)p >= (u8 *)filename_16 + sizeof(filename_16)) + break; + + if (*str == '/') { + *p++ = '\\'; + str++; + } else { + *p++ = *str++; + } + } + + *p = '\0'; + + /* Only open the volume once. */ + if (!i) { + efi_boot_services_t *boottime; + + boottime = sys_table_arg->boottime; + + status = efi_call_phys3(boottime->handle_protocol, + image->device_handle, &fs_proto, + (void **)&io); + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to handle fs_proto\n"); + goto free_files; + } + + status = efi_call_phys2(io->open_volume, io, &fh); + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to open volume\n"); + goto free_files; + } + } + + status = efi_call_phys5(fh->open, fh, &h, filename_16, + EFI_FILE_MODE_READ, (u64)0); + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to open file: "); + efi_char16_printk(sys_table_arg, filename_16); + efi_printk(sys_table_arg, "\n"); + goto close_handles; + } + + file->handle = h; + + info_sz = 0; + status = efi_call_phys4(h->get_info, h, &info_guid, + &info_sz, NULL); + if (status != EFI_BUFFER_TOO_SMALL) { + efi_printk(sys_table_arg, "Failed to get file info size\n"); + goto close_handles; + } + +grow: + status = efi_call_phys3(sys_table_arg->boottime->allocate_pool, + EFI_LOADER_DATA, info_sz, + (void **)&info); + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to alloc mem for file info\n"); + goto close_handles; + } + + status = efi_call_phys4(h->get_info, h, &info_guid, + &info_sz, info); + if (status == EFI_BUFFER_TOO_SMALL) { + efi_call_phys1(sys_table_arg->boottime->free_pool, + info); + goto grow; + } + + file_sz = info->file_size; + efi_call_phys1(sys_table_arg->boottime->free_pool, info); + + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to get file info\n"); + goto close_handles; + } + + file->size = file_sz; + file_size_total += file_sz; + } + + if (file_size_total) { + unsigned long addr; + + /* + * Multiple files need to be at consecutive addresses in memory, + * so allocate enough memory for all the files. This is used + * for loading multiple files. + */ + status = efi_high_alloc(sys_table_arg, file_size_total, 0x1000, + &file_addr, max_addr); + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to alloc highmem for files\n"); + goto close_handles; + } + + /* We've run out of free low memory. */ + if (file_addr > max_addr) { + efi_printk(sys_table_arg, "We've run out of free low memory\n"); + status = EFI_INVALID_PARAMETER; + goto free_file_total; + } + + addr = file_addr; + for (j = 0; j < nr_files; j++) { + unsigned long size; + + size = files[j].size; + while (size) { + unsigned long chunksize; + if (size > EFI_READ_CHUNK_SIZE) + chunksize = EFI_READ_CHUNK_SIZE; + else + chunksize = size; + status = efi_call_phys3(fh->read, + files[j].handle, + &chunksize, + (void *)addr); + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "Failed to read file\n"); + goto free_file_total; + } + addr += chunksize; + size -= chunksize; + } + + efi_call_phys1(fh->close, files[j].handle); + } + + } + + efi_call_phys1(sys_table_arg->boottime->free_pool, files); + + *load_addr = file_addr; + *load_size = file_size_total; + + return status; + +free_file_total: + efi_free(sys_table_arg, file_size_total, file_addr); + +close_handles: + for (k = j; k < i; k++) + efi_call_phys1(fh->close, files[k].handle); +free_files: + efi_call_phys1(sys_table_arg->boottime->free_pool, files); +fail: + *load_addr = 0; + *load_size = 0; + + return status; +} +/* + * Relocate a kernel image, either compressed or uncompressed. + * In the ARM64 case, all kernel images are currently + * uncompressed, and as such when we relocate it we need to + * allocate additional space for the BSS segment. Any low + * memory that this function should avoid needs to be + * unavailable in the EFI memory map, as if the preferred + * address is not available the lowest available address will + * be used. + */ +static efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg, + unsigned long *image_addr, + unsigned long image_size, + unsigned long alloc_size, + unsigned long preferred_addr, + unsigned long alignment) +{ + unsigned long cur_image_addr; + unsigned long new_addr = 0; + efi_status_t status; + unsigned long nr_pages; + efi_physical_addr_t efi_addr = preferred_addr; + + if (!image_addr || !image_size || !alloc_size) + return EFI_INVALID_PARAMETER; + if (alloc_size < image_size) + return EFI_INVALID_PARAMETER; + + cur_image_addr = *image_addr; + + /* + * The EFI firmware loader could have placed the kernel image + * anywhere in memory, but the kernel has restrictions on the + * max physical address it can run at. Some architectures + * also have a prefered address, so first try to relocate + * to the preferred address. If that fails, allocate as low + * as possible while respecting the required alignment. + */ + nr_pages = round_up(alloc_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; + status = efi_call_phys4(sys_table_arg->boottime->allocate_pages, + EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA, + nr_pages, &efi_addr); + new_addr = efi_addr; + /* + * If preferred address allocation failed allocate as low as + * possible. + */ + if (status != EFI_SUCCESS) { + status = efi_low_alloc(sys_table_arg, alloc_size, alignment, + &new_addr); + } + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, "ERROR: Failed to allocate usable memory for kernel.\n"); + return status; + } + + /* + * We know source/dest won't overlap since both memory ranges + * have been allocated by UEFI, so we can safely use memcpy. + */ + memcpy((void *)new_addr, (void *)cur_image_addr, image_size); + + /* Return the new address of the relocated image. */ + *image_addr = new_addr; + + return status; +} + +/* + * Convert the unicode UEFI command line to ASCII to pass to kernel. + * Size of memory allocated return in *cmd_line_len. + * Returns NULL on error. + */ +static char *efi_convert_cmdline_to_ascii(efi_system_table_t *sys_table_arg, + efi_loaded_image_t *image, + int *cmd_line_len) +{ + u16 *s2; + u8 *s1 = NULL; + unsigned long cmdline_addr = 0; + int load_options_size = image->load_options_size / 2; /* ASCII */ + void *options = image->load_options; + int options_size = 0; + efi_status_t status; + int i; + u16 zero = 0; + + if (options) { + s2 = options; + while (*s2 && *s2 != '\n' && options_size < load_options_size) { + s2++; + options_size++; + } + } + + if (options_size == 0) { + /* No command line options, so return empty string*/ + options_size = 1; + options = &zero; + } + + options_size++; /* NUL termination */ +#ifdef CONFIG_ARM + /* + * For ARM, allocate at a high address to avoid reserved + * regions at low addresses that we don't know the specfics of + * at the time we are processing the command line. + */ + status = efi_high_alloc(sys_table_arg, options_size, 0, + &cmdline_addr, 0xfffff000); +#else + status = efi_low_alloc(sys_table_arg, options_size, 0, + &cmdline_addr); +#endif + if (status != EFI_SUCCESS) + return NULL; + + s1 = (u8 *)cmdline_addr; + s2 = (u16 *)options; + + for (i = 0; i < options_size - 1; i++) + *s1++ = *s2++; + + *s1 = '\0'; + + *cmd_line_len = options_size; + return (char *)cmdline_addr; +} |