[linux-2.6-block.git] / drivers / firmware / efi / libstub / efi-stub-helper.c

/*
 * 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.
 *
 */

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

#include "efistub.h"

/*
 * Some firmware implementations have problems reading files in one go.
 * A read chunk size of 1MB seems to work for most platforms.
 *
 * Unfortunately, reading files in chunks triggers *other* bugs on some
 * platforms, so we provide a way to disable this workaround, which can
 * be done by passing "efi=nochunk" on the EFI boot stub command line.
 *
 * If you experience issues with initrd images being corrupt it's worth
 * trying efi=nochunk, but chunking is enabled by default because there
 * are far more machines that require the workaround than those that
 * break with it enabled.
 */
#define EFI_READ_CHUNK_SIZE	(1024 * 1024)

static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE;

struct file_info {
	efi_file_handle_t *handle;
	u64 size;
};

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);
	}
}

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_early(allocate_pool, EFI_LOADER_DATA,
				*map_size, (void **)&m);
	if (status != EFI_SUCCESS)
		goto fail;

	*desc_size = 0;
	key = 0;
	status = efi_call_early(get_memory_map, map_size, m,
				&key, desc_size, &desc_version);
	if (status == EFI_BUFFER_TOO_SMALL) {
		efi_call_early(free_pool, m);
		goto again;
	}

	if (status != EFI_SUCCESS)
		efi_call_early(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;
}


unsigned long get_dram_base(efi_system_table_t *sys_table_arg)
{
	efi_status_t status;
	unsigned long map_size;
	unsigned long membase  = EFI_ERROR;
	struct efi_memory_map map;
	efi_memory_desc_t *md;

	status = efi_get_memory_map(sys_table_arg, (efi_memory_desc_t **)&map.map,
				    &map_size, &map.desc_size, NULL, NULL);
	if (status != EFI_SUCCESS)
		return membase;

	map.map_end = map.map + map_size;

	for_each_efi_memory_desc(&map, md)
		if (md->attribute & EFI_MEMORY_WB)
			if (membase > md->phys_addr)
				membase = md->phys_addr;

	efi_call_early(free_pool, map.map);

	return membase;
}

/*
 * Allocate at the highest possible address that is not above 'max'.
 */
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_early(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_early(free_pool, map);
fail:
	return status;
}

/*
 * Allocate at the lowest possible address.
 */
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_early(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_early(free_pool, map);
fail:
	return status;
}

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_early(free_pages, addr, nr_pages);
}

/*
 * Parse the ASCII string 'cmdline' for EFI options, denoted by the efi=
 * option, e.g. efi=nochunk.
 *
 * It should be noted that efi= is parsed in two very different
 * environments, first in the early boot environment of the EFI boot
 * stub, and subsequently during the kernel boot.
 */
efi_status_t efi_parse_options(char *cmdline)
{
	char *str;

	/*
	 * If no EFI parameters were specified on the cmdline we've got
	 * nothing to do.
	 */
	str = strstr(cmdline, "efi=");
	if (!str)
		return EFI_SUCCESS;

	/* Skip ahead to first argument */
	str += strlen("efi=");

	/*
	 * Remember, because efi= is also used by the kernel we need to
	 * skip over arguments we don't understand.
	 */
	while (*str) {
		if (!strncmp(str, "nochunk", 7)) {
			str += strlen("nochunk");
			__chunk_size = -1UL;
		}

		/* Group words together, delimited by "," */
		while (*str && *str != ',')
			str++;

		if (*str == ',')
			str++;
	}

	return EFI_SUCCESS;
}

/*
 * Check the cmdline for a LILO-style file= arguments.
 *
 * We only support loading a file from the same filesystem as
 * the kernel image.
 */
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;
	u64 file_size_total;
	efi_file_handle_t *fh = NULL;
	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_early(allocate_pool, EFI_LOADER_DATA,
				nr_files * sizeof(*files), (void **)&files);
	if (status != EFI_SUCCESS) {
		pr_efi_err(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_char16_t filename_16[256];
		efi_char16_t *p;

		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) {
			status = efi_open_volume(sys_table_arg, image,
						 (void **)&fh);
			if (status != EFI_SUCCESS)
				goto free_files;
		}

		status = efi_file_size(sys_table_arg, fh, filename_16,
				       (void **)&file->handle, &file->size);
		if (status != EFI_SUCCESS)
			goto close_handles;

		file_size_total += file->size;
	}

	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) {
			pr_efi_err(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) {
			pr_efi_err(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 > __chunk_size)
					chunksize = __chunk_size;
				else
					chunksize = size;

				status = efi_file_read(files[j].handle,
						       &chunksize,
						       (void *)addr);
				if (status != EFI_SUCCESS) {
					pr_efi_err(sys_table_arg, "Failed to read file\n");
					goto free_file_total;
				}
				addr += chunksize;
				size -= chunksize;
			}

			efi_file_close(files[j].handle);
		}

	}

	efi_call_early(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_file_close(files[k].handle);
free_files:
	efi_call_early(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.
 */
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_early(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) {
		pr_efi_err(sys_table_arg, "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;
}

/*
 * Get the number of UTF-8 bytes corresponding to an UTF-16 character.
 * This overestimates for surrogates, but that is okay.
 */
static int efi_utf8_bytes(u16 c)
{
	return 1 + (c >= 0x80) + (c >= 0x800);
}

/*
 * Convert an UTF-16 string, not necessarily null terminated, to UTF-8.
 */
static u8 *efi_utf16_to_utf8(u8 *dst, const u16 *src, int n)
{
	unsigned int c;

	while (n--) {
		c = *src++;
		if (n && c >= 0xd800 && c <= 0xdbff &&
		    *src >= 0xdc00 && *src <= 0xdfff) {
			c = 0x10000 + ((c & 0x3ff) << 10) + (*src & 0x3ff);
			src++;
			n--;
		}
		if (c >= 0xd800 && c <= 0xdfff)
			c = 0xfffd; /* Unmatched surrogate */
		if (c < 0x80) {
			*dst++ = c;
			continue;
		}
		if (c < 0x800) {
			*dst++ = 0xc0 + (c >> 6);
			goto t1;
		}
		if (c < 0x10000) {
			*dst++ = 0xe0 + (c >> 12);
			goto t2;
		}
		*dst++ = 0xf0 + (c >> 18);
		*dst++ = 0x80 + ((c >> 12) & 0x3f);
	t2:
		*dst++ = 0x80 + ((c >> 6) & 0x3f);
	t1:
		*dst++ = 0x80 + (c & 0x3f);
	}

	return dst;
}

/*
 * 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.
 */
char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
			  efi_loaded_image_t *image,
			  int *cmd_line_len)
{
	const u16 *s2;
	u8 *s1 = NULL;
	unsigned long cmdline_addr = 0;
	int load_options_chars = image->load_options_size / 2; /* UTF-16 */
	const u16 *options = image->load_options;
	int options_bytes = 0;  /* UTF-8 bytes */
	int options_chars = 0;  /* UTF-16 chars */
	efi_status_t status;
	u16 zero = 0;

	if (options) {
		s2 = options;
		while (*s2 && *s2 != '\n'
		       && options_chars < load_options_chars) {
			options_bytes += efi_utf8_bytes(*s2++);
			options_chars++;
		}
	}

	if (!options_chars) {
		/* No command line options, so return empty string*/
		options = &zero;
	}

	options_bytes++;	/* NUL termination */

	status = efi_low_alloc(sys_table_arg, options_bytes, 0, &cmdline_addr);
	if (status != EFI_SUCCESS)
		return NULL;

	s1 = (u8 *)cmdline_addr;
	s2 = (const u16 *)options;

	s1 = efi_utf16_to_utf8(s1, s2, options_chars);
	*s1 = '\0';

	*cmd_line_len = options_bytes;
	return (char *)cmdline_addr;
}
Commit	Line	Data
7721da4c RF	1	/*
	2	* Helper functions used by the EFI stub on multiple
	3	* architectures. This should be #included by the EFI stub
	4	* implementation files.
	5	*
	6	* Copyright 2011 Intel Corporation; author Matt Fleming
	7	*
	8	* This file is part of the Linux kernel, and is made available
	9	* under the terms of the GNU General Public License version 2.
	10	*
	11	*/
7721da4c	12
bd669475 AB	13	#include <linux/efi.h>
	14	#include <asm/efi.h>
	15
	16	#include "efistub.h"
9bb40191	17
5a17dae4 MF	18	/*
	19	* Some firmware implementations have problems reading files in one go.
	20	* A read chunk size of 1MB seems to work for most platforms.
	21	*
	22	* Unfortunately, reading files in chunks triggers other bugs on some
	23	* platforms, so we provide a way to disable this workaround, which can
	24	* be done by passing "efi=nochunk" on the EFI boot stub command line.
	25	*
	26	* If you experience issues with initrd images being corrupt it's worth
	27	* trying efi=nochunk, but chunking is enabled by default because there
	28	* are far more machines that require the workaround than those that
	29	* break with it enabled.
	30	*/
bd669475	31	#define EFI_READ_CHUNK_SIZE (1024 * 1024)
9bb40191	32
5a17dae4 MF	33	static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE;
5a17dae4 MF	34
36f8961c	35	struct file_info {
7721da4c RF	36	efi_file_handle_t *handle;
	37	u64 size;
	38	};
	39
bd669475	40	void efi_printk(efi_system_table_t sys_table_arg, char str)
7721da4c RF	41	{
	42	char *s8;
	43
	44	for (s8 = str; *s8; s8++) {
	45	efi_char16_t ch[2] = { 0 };
	46
	47	ch[0] = *s8;
	48	if (*s8 == '\n') {
	49	efi_char16_t nl[2] = { '\r', 0 };
876dc36a	50	efi_char16_printk(sys_table_arg, nl);
7721da4c RF	51	}
7721da4c RF	52
876dc36a	53	efi_char16_printk(sys_table_arg, ch);
7721da4c RF	54	}
	55	}
	56
bd669475 AB	57	efi_status_t efi_get_memory_map(efi_system_table_t *sys_table_arg,
	58	efi_memory_desc_t **map,
	59	unsigned long *map_size,
	60	unsigned long *desc_size,
	61	u32 *desc_ver,
	62	unsigned long *key_ptr)
7721da4c RF	63	{
	64	efi_memory_desc_t *m = NULL;
	65	efi_status_t status;
	66	unsigned long key;
	67	u32 desc_version;
	68
43a9f696 MF	69	map_size = sizeof(m) * 32;
43a9f696 MF	70	again:
7721da4c RF	71	/*
	72	* Add an additional efi_memory_desc_t because we're doing an
	73	* allocation which may be in a new descriptor region.
	74	*/
43a9f696	75	map_size += sizeof(m);
204b0a1a MF	76	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
204b0a1a MF	77	map_size, (void *)&m);
7721da4c RF	78	if (status != EFI_SUCCESS)
	79	goto fail;
	80
43a9f696 MF	81	*desc_size = 0;
43a9f696 MF	82	key = 0;
204b0a1a MF	83	status = efi_call_early(get_memory_map, map_size, m,
204b0a1a MF	84	&key, desc_size, &desc_version);
7721da4c	85	if (status == EFI_BUFFER_TOO_SMALL) {
204b0a1a	86	efi_call_early(free_pool, m);
43a9f696	87	goto again;
7721da4c RF	88	}
	89
	90	if (status != EFI_SUCCESS)
204b0a1a	91	efi_call_early(free_pool, m);
54b52d87	92
1c089c65 RF	93	if (key_ptr && status == EFI_SUCCESS)
	94	*key_ptr = key;
	95	if (desc_ver && status == EFI_SUCCESS)
	96	*desc_ver = desc_version;
7721da4c RF	97
	98	fail:
	99	*map = m;
	100	return status;
	101	}
	102
9bb40191	103
ddeeefe2	104	unsigned long get_dram_base(efi_system_table_t *sys_table_arg)
9bb40191 RF	105	{
	106	efi_status_t status;
	107	unsigned long map_size;
	108	unsigned long membase = EFI_ERROR;
	109	struct efi_memory_map map;
	110	efi_memory_desc_t *md;
	111
	112	status = efi_get_memory_map(sys_table_arg, (efi_memory_desc_t **)&map.map,
	113	&map_size, &map.desc_size, NULL, NULL);
	114	if (status != EFI_SUCCESS)
	115	return membase;
	116
	117	map.map_end = map.map + map_size;
	118
	119	for_each_efi_memory_desc(&map, md)
	120	if (md->attribute & EFI_MEMORY_WB)
	121	if (membase > md->phys_addr)
	122	membase = md->phys_addr;
	123
	124	efi_call_early(free_pool, map.map);
	125
	126	return membase;
	127	}
	128
7721da4c RF	129	/*
	130	* Allocate at the highest possible address that is not above 'max'.
	131	*/
bd669475 AB	132	efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
	133	unsigned long size, unsigned long align,
	134	unsigned long *addr, unsigned long max)
7721da4c RF	135	{
	136	unsigned long map_size, desc_size;
	137	efi_memory_desc_t *map;
	138	efi_status_t status;
	139	unsigned long nr_pages;
	140	u64 max_addr = 0;
	141	int i;
	142
1c089c65 RF	143	status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
1c089c65 RF	144	NULL, NULL);
7721da4c RF	145	if (status != EFI_SUCCESS)
	146	goto fail;
	147
38dd9c02 RF	148	/*
	149	* Enforce minimum alignment that EFI requires when requesting
	150	* a specific address. We are doing page-based allocations,
	151	* so we must be aligned to a page.
	152	*/
	153	if (align < EFI_PAGE_SIZE)
	154	align = EFI_PAGE_SIZE;
	155
7721da4c RF	156	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
	157	again:
	158	for (i = 0; i < map_size / desc_size; i++) {
	159	efi_memory_desc_t *desc;
	160	unsigned long m = (unsigned long)map;
	161	u64 start, end;
	162
	163	desc = (efi_memory_desc_t )(m + (i desc_size));
	164	if (desc->type != EFI_CONVENTIONAL_MEMORY)
	165	continue;
	166
	167	if (desc->num_pages < nr_pages)
	168	continue;
	169
	170	start = desc->phys_addr;
	171	end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
	172
	173	if ((start + size) > end \|\| (start + size) > max)
	174	continue;
	175
	176	if (end - size > max)
	177	end = max;
	178
	179	if (round_down(end - size, align) < start)
	180	continue;
	181
	182	start = round_down(end - size, align);
	183
	184	/*
	185	* Don't allocate at 0x0. It will confuse code that
	186	* checks pointers against NULL.
	187	*/
	188	if (start == 0x0)
	189	continue;
	190
	191	if (start > max_addr)
	192	max_addr = start;
	193	}
	194
	195	if (!max_addr)
	196	status = EFI_NOT_FOUND;
	197	else {
204b0a1a MF	198	status = efi_call_early(allocate_pages,
	199	EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
	200	nr_pages, &max_addr);
7721da4c RF	201	if (status != EFI_SUCCESS) {
	202	max = max_addr;
	203	max_addr = 0;
	204	goto again;
	205	}
	206
	207	*addr = max_addr;
	208	}
	209
204b0a1a	210	efi_call_early(free_pool, map);
7721da4c RF	211	fail:
	212	return status;
	213	}
	214
	215	/*
	216	* Allocate at the lowest possible address.
	217	*/
bd669475 AB	218	efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
	219	unsigned long size, unsigned long align,
	220	unsigned long *addr)
7721da4c RF	221	{
	222	unsigned long map_size, desc_size;
	223	efi_memory_desc_t *map;
	224	efi_status_t status;
	225	unsigned long nr_pages;
	226	int i;
	227
1c089c65 RF	228	status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
1c089c65 RF	229	NULL, NULL);
7721da4c RF	230	if (status != EFI_SUCCESS)
	231	goto fail;
	232
38dd9c02 RF	233	/*
	234	* Enforce minimum alignment that EFI requires when requesting
	235	* a specific address. We are doing page-based allocations,
	236	* so we must be aligned to a page.
	237	*/
	238	if (align < EFI_PAGE_SIZE)
	239	align = EFI_PAGE_SIZE;
	240
7721da4c RF	241	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
	242	for (i = 0; i < map_size / desc_size; i++) {
	243	efi_memory_desc_t *desc;
	244	unsigned long m = (unsigned long)map;
	245	u64 start, end;
	246
	247	desc = (efi_memory_desc_t )(m + (i desc_size));
	248
	249	if (desc->type != EFI_CONVENTIONAL_MEMORY)
	250	continue;
	251
	252	if (desc->num_pages < nr_pages)
	253	continue;
	254
	255	start = desc->phys_addr;
	256	end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
	257
	258	/*
	259	* Don't allocate at 0x0. It will confuse code that
	260	* checks pointers against NULL. Skip the first 8
	261	* bytes so we start at a nice even number.
	262	*/
	263	if (start == 0x0)
	264	start += 8;
	265
	266	start = round_up(start, align);
	267	if ((start + size) > end)
	268	continue;
	269
204b0a1a MF	270	status = efi_call_early(allocate_pages,
	271	EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
	272	nr_pages, &start);
7721da4c RF	273	if (status == EFI_SUCCESS) {
	274	*addr = start;
	275	break;
	276	}
	277	}
	278
	279	if (i == map_size / desc_size)
	280	status = EFI_NOT_FOUND;
	281
204b0a1a	282	efi_call_early(free_pool, map);
7721da4c RF	283	fail:
	284	return status;
	285	}
	286
bd669475 AB	287	void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
bd669475 AB	288	unsigned long addr)
7721da4c RF	289	{
	290	unsigned long nr_pages;
	291
0e1cadb0 RF	292	if (!size)
	293	return;
	294
7721da4c	295	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
204b0a1a	296	efi_call_early(free_pages, addr, nr_pages);
7721da4c RF	297	}
7721da4c RF	298
5a17dae4 MF	299	/*
	300	* Parse the ASCII string 'cmdline' for EFI options, denoted by the efi=
	301	* option, e.g. efi=nochunk.
	302	*
	303	* It should be noted that efi= is parsed in two very different
	304	* environments, first in the early boot environment of the EFI boot
	305	* stub, and subsequently during the kernel boot.
	306	*/
	307	efi_status_t efi_parse_options(char *cmdline)
	308	{
	309	char *str;
	310
	311	/*
	312	* If no EFI parameters were specified on the cmdline we've got
	313	* nothing to do.
	314	*/
	315	str = strstr(cmdline, "efi=");
	316	if (!str)
	317	return EFI_SUCCESS;
	318
	319	/* Skip ahead to first argument */
	320	str += strlen("efi=");
	321
	322	/*
	323	* Remember, because efi= is also used by the kernel we need to
	324	* skip over arguments we don't understand.
	325	*/
	326	while (*str) {
	327	if (!strncmp(str, "nochunk", 7)) {
	328	str += strlen("nochunk");
	329	__chunk_size = -1UL;
	330	}
	331
	332	/* Group words together, delimited by "," */
	333	while (str && str != ',')
	334	str++;
	335
	336	if (*str == ',')
	337	str++;
	338	}
	339
	340	return EFI_SUCCESS;
	341	}
7721da4c RF	342
7721da4c RF	343	/*
36f8961c	344	* Check the cmdline for a LILO-style file= arguments.
7721da4c	345	*
36f8961c RF	346	* We only support loading a file from the same filesystem as
36f8961c RF	347	* the kernel image.
7721da4c	348	*/
bd669475 AB	349	efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg,
	350	efi_loaded_image_t *image,
	351	char cmd_line, char option_string,
	352	unsigned long max_addr,
	353	unsigned long *load_addr,
	354	unsigned long *load_size)
7721da4c	355	{
36f8961c RF	356	struct file_info *files;
36f8961c RF	357	unsigned long file_addr;
36f8961c	358	u64 file_size_total;
9403e462	359	efi_file_handle_t *fh = NULL;
7721da4c	360	efi_status_t status;
36f8961c	361	int nr_files;
7721da4c RF	362	char *str;
	363	int i, j, k;
	364
36f8961c RF	365	file_addr = 0;
36f8961c RF	366	file_size_total = 0;
7721da4c	367
46f4582e	368	str = cmd_line;
7721da4c RF	369
	370	j = 0; /* See close_handles */
	371
46f4582e RF	372	if (!load_addr \|\| !load_size)
	373	return EFI_INVALID_PARAMETER;
	374
	375	*load_addr = 0;
	376	*load_size = 0;
	377
7721da4c RF	378	if (!str \|\| !*str)
	379	return EFI_SUCCESS;
	380
36f8961c	381	for (nr_files = 0; *str; nr_files++) {
46f4582e	382	str = strstr(str, option_string);
7721da4c RF	383	if (!str)
	384	break;
	385
46f4582e	386	str += strlen(option_string);
7721da4c RF	387
	388	/* Skip any leading slashes */
	389	while (str == '/' \|\| str == '\\')
	390	str++;
	391
	392	while (str && str != ' ' && *str != '\n')
	393	str++;
	394	}
	395
36f8961c	396	if (!nr_files)
7721da4c RF	397	return EFI_SUCCESS;
7721da4c RF	398
204b0a1a MF	399	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
204b0a1a MF	400	nr_files * sizeof(files), (void *)&files);
7721da4c	401	if (status != EFI_SUCCESS) {
f966ea02	402	pr_efi_err(sys_table_arg, "Failed to alloc mem for file handle list\n");
7721da4c RF	403	goto fail;
	404	}
	405
46f4582e	406	str = cmd_line;
36f8961c RF	407	for (i = 0; i < nr_files; i++) {
36f8961c RF	408	struct file_info *file;
7721da4c	409	efi_char16_t filename_16[256];
7721da4c	410	efi_char16_t *p;
7721da4c	411
46f4582e	412	str = strstr(str, option_string);
7721da4c RF	413	if (!str)
	414	break;
	415
46f4582e	416	str += strlen(option_string);
7721da4c	417
36f8961c	418	file = &files[i];
7721da4c RF	419	p = filename_16;
	420
	421	/* Skip any leading slashes */
	422	while (str == '/' \|\| str == '\\')
	423	str++;
	424
	425	while (str && str != ' ' && *str != '\n') {
	426	if ((u8 )p >= (u8 )filename_16 + sizeof(filename_16))
	427	break;
	428
	429	if (*str == '/') {
	430	*p++ = '\\';
4e283088	431	str++;
7721da4c RF	432	} else {
	433	p++ = str++;
	434	}
	435	}
	436
	437	*p = '\0';
	438
	439	/* Only open the volume once. */
	440	if (!i) {
54b52d87 MF	441	status = efi_open_volume(sys_table_arg, image,
	442	(void **)&fh);
	443	if (status != EFI_SUCCESS)
36f8961c	444	goto free_files;
7721da4c RF	445	}
7721da4c RF	446
54b52d87 MF	447	status = efi_file_size(sys_table_arg, fh, filename_16,
	448	(void **)&file->handle, &file->size);
	449	if (status != EFI_SUCCESS)
7721da4c	450	goto close_handles;
7721da4c	451
54b52d87	452	file_size_total += file->size;
7721da4c RF	453	}
7721da4c RF	454
36f8961c	455	if (file_size_total) {
7721da4c RF	456	unsigned long addr;
	457
	458	/*
36f8961c RF	459	* Multiple files need to be at consecutive addresses in memory,
	460	* so allocate enough memory for all the files. This is used
	461	* for loading multiple files.
7721da4c	462	*/
36f8961c RF	463	status = efi_high_alloc(sys_table_arg, file_size_total, 0x1000,
36f8961c RF	464	&file_addr, max_addr);
7721da4c	465	if (status != EFI_SUCCESS) {
f966ea02	466	pr_efi_err(sys_table_arg, "Failed to alloc highmem for files\n");
7721da4c RF	467	goto close_handles;
	468	}
	469
	470	/* We've run out of free low memory. */
36f8961c	471	if (file_addr > max_addr) {
f966ea02	472	pr_efi_err(sys_table_arg, "We've run out of free low memory\n");
7721da4c	473	status = EFI_INVALID_PARAMETER;
36f8961c	474	goto free_file_total;
7721da4c RF	475	}
7721da4c RF	476
36f8961c RF	477	addr = file_addr;
36f8961c RF	478	for (j = 0; j < nr_files; j++) {
6a5fe770	479	unsigned long size;
7721da4c	480
36f8961c	481	size = files[j].size;
7721da4c	482	while (size) {
6a5fe770	483	unsigned long chunksize;
5a17dae4 MF	484	if (size > __chunk_size)
5a17dae4 MF	485	chunksize = __chunk_size;
7721da4c RF	486	else
7721da4c RF	487	chunksize = size;
54b52d87	488
47514c99	489	status = efi_file_read(files[j].handle,
54b52d87 MF	490	&chunksize,
54b52d87 MF	491	(void *)addr);
7721da4c	492	if (status != EFI_SUCCESS) {
f966ea02	493	pr_efi_err(sys_table_arg, "Failed to read file\n");
36f8961c	494	goto free_file_total;
7721da4c RF	495	}
	496	addr += chunksize;
	497	size -= chunksize;
	498	}
	499
47514c99	500	efi_file_close(files[j].handle);
7721da4c RF	501	}
	502
	503	}
	504
204b0a1a	505	efi_call_early(free_pool, files);
7721da4c	506
36f8961c RF	507	*load_addr = file_addr;
36f8961c RF	508	*load_size = file_size_total;
7721da4c RF	509
	510	return status;
	511
36f8961c RF	512	free_file_total:
36f8961c RF	513	efi_free(sys_table_arg, file_size_total, file_addr);
7721da4c RF	514
	515	close_handles:
	516	for (k = j; k < i; k++)
47514c99	517	efi_file_close(files[k].handle);
36f8961c	518	free_files:
204b0a1a	519	efi_call_early(free_pool, files);
7721da4c	520	fail:
46f4582e RF	521	*load_addr = 0;
46f4582e RF	522	*load_size = 0;
7721da4c RF	523
	524	return status;
	525	}
4a9f3a7c RF	526	/*
	527	* Relocate a kernel image, either compressed or uncompressed.
	528	* In the ARM64 case, all kernel images are currently
	529	* uncompressed, and as such when we relocate it we need to
	530	* allocate additional space for the BSS segment. Any low
	531	* memory that this function should avoid needs to be
	532	* unavailable in the EFI memory map, as if the preferred
	533	* address is not available the lowest available address will
	534	* be used.
	535	*/
bd669475 AB	536	efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg,
	537	unsigned long *image_addr,
	538	unsigned long image_size,
	539	unsigned long alloc_size,
	540	unsigned long preferred_addr,
	541	unsigned long alignment)
c6866d72	542	{
4a9f3a7c RF	543	unsigned long cur_image_addr;
4a9f3a7c RF	544	unsigned long new_addr = 0;
c6866d72	545	efi_status_t status;
4a9f3a7c RF	546	unsigned long nr_pages;
	547	efi_physical_addr_t efi_addr = preferred_addr;
	548
	549	if (!image_addr \|\| !image_size \|\| !alloc_size)
	550	return EFI_INVALID_PARAMETER;
	551	if (alloc_size < image_size)
	552	return EFI_INVALID_PARAMETER;
	553
	554	cur_image_addr = *image_addr;
c6866d72 RF	555
	556	/*
	557	* The EFI firmware loader could have placed the kernel image
4a9f3a7c RF	558	* anywhere in memory, but the kernel has restrictions on the
	559	* max physical address it can run at. Some architectures
	560	* also have a prefered address, so first try to relocate
	561	* to the preferred address. If that fails, allocate as low
	562	* as possible while respecting the required alignment.
c6866d72	563	*/
4a9f3a7c	564	nr_pages = round_up(alloc_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
204b0a1a MF	565	status = efi_call_early(allocate_pages,
	566	EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
	567	nr_pages, &efi_addr);
4a9f3a7c RF	568	new_addr = efi_addr;
	569	/*
	570	* If preferred address allocation failed allocate as low as
	571	* possible.
	572	*/
c6866d72	573	if (status != EFI_SUCCESS) {
4a9f3a7c RF	574	status = efi_low_alloc(sys_table_arg, alloc_size, alignment,
	575	&new_addr);
	576	}
	577	if (status != EFI_SUCCESS) {
f966ea02	578	pr_efi_err(sys_table_arg, "Failed to allocate usable memory for kernel.\n");
4a9f3a7c	579	return status;
c6866d72 RF	580	}
c6866d72 RF	581
4a9f3a7c RF	582	/*
	583	* We know source/dest won't overlap since both memory ranges
	584	* have been allocated by UEFI, so we can safely use memcpy.
	585	*/
	586	memcpy((void )new_addr, (void )cur_image_addr, image_size);
c6866d72	587
4a9f3a7c RF	588	/* Return the new address of the relocated image. */
4a9f3a7c RF	589	*image_addr = new_addr;
c6866d72 RF	590
	591	return status;
	592	}
5fef3870	593
c625d1c2 PA	594	/*
	595	* Get the number of UTF-8 bytes corresponding to an UTF-16 character.
	596	* This overestimates for surrogates, but that is okay.
	597	*/
	598	static int efi_utf8_bytes(u16 c)
	599	{
	600	return 1 + (c >= 0x80) + (c >= 0x800);
	601	}
	602
	603	/*
	604	* Convert an UTF-16 string, not necessarily null terminated, to UTF-8.
	605	*/
	606	static u8 efi_utf16_to_utf8(u8 dst, const u16 *src, int n)
	607	{
	608	unsigned int c;
	609
	610	while (n--) {
	611	c = *src++;
	612	if (n && c >= 0xd800 && c <= 0xdbff &&
	613	src >= 0xdc00 && src <= 0xdfff) {
	614	c = 0x10000 + ((c & 0x3ff) << 10) + (*src & 0x3ff);
	615	src++;
	616	n--;
	617	}
	618	if (c >= 0xd800 && c <= 0xdfff)
	619	c = 0xfffd; /* Unmatched surrogate */
	620	if (c < 0x80) {
	621	*dst++ = c;
	622	continue;
	623	}
	624	if (c < 0x800) {
	625	*dst++ = 0xc0 + (c >> 6);
	626	goto t1;
	627	}
	628	if (c < 0x10000) {
	629	*dst++ = 0xe0 + (c >> 12);
	630	goto t2;
	631	}
	632	*dst++ = 0xf0 + (c >> 18);
	633	*dst++ = 0x80 + ((c >> 12) & 0x3f);
	634	t2:
	635	*dst++ = 0x80 + ((c >> 6) & 0x3f);
	636	t1:
	637	*dst++ = 0x80 + (c & 0x3f);
	638	}
	639
	640	return dst;
	641	}
	642
5fef3870 RF	643	/*
	644	* Convert the unicode UEFI command line to ASCII to pass to kernel.
	645	* Size of memory allocated return in *cmd_line_len.
	646	* Returns NULL on error.
	647	*/
bd669475 AB	648	char efi_convert_cmdline(efi_system_table_t sys_table_arg,
	649	efi_loaded_image_t *image,
	650	int *cmd_line_len)
5fef3870	651	{
c625d1c2	652	const u16 *s2;
5fef3870 RF	653	u8 *s1 = NULL;
5fef3870 RF	654	unsigned long cmdline_addr = 0;
c625d1c2 PA	655	int load_options_chars = image->load_options_size / 2; /* UTF-16 */
	656	const u16 *options = image->load_options;
	657	int options_bytes = 0; /* UTF-8 bytes */
	658	int options_chars = 0; /* UTF-16 chars */
5fef3870	659	efi_status_t status;
5fef3870 RF	660	u16 zero = 0;
	661
	662	if (options) {
	663	s2 = options;
c625d1c2 PA	664	while (s2 && s2 != '\n'
	665	&& options_chars < load_options_chars) {
	666	options_bytes += efi_utf8_bytes(*s2++);
	667	options_chars++;
5fef3870 RF	668	}
	669	}
	670
c625d1c2	671	if (!options_chars) {
5fef3870	672	/* No command line options, so return empty string*/
5fef3870 RF	673	options = &zero;
	674	}
	675
c625d1c2	676	options_bytes++; /* NUL termination */
9403e462	677
c625d1c2	678	status = efi_low_alloc(sys_table_arg, options_bytes, 0, &cmdline_addr);
5fef3870 RF	679	if (status != EFI_SUCCESS)
	680	return NULL;
	681
	682	s1 = (u8 *)cmdline_addr;
c625d1c2	683	s2 = (const u16 *)options;
5fef3870	684
c625d1c2	685	s1 = efi_utf16_to_utf8(s1, s2, options_chars);
5fef3870 RF	686	*s1 = '\0';
5fef3870 RF	687
c625d1c2	688	*cmd_line_len = options_bytes;
5fef3870 RF	689	return (char *)cmdline_addr;
5fef3870 RF	690	}