[linux-2.6-block.git] / arch / x86 / boot / compressed / misc.c

/*
 * misc.c
 *
 * This is a collection of several routines used to extract the kernel
 * which includes KASLR relocation, decompression, ELF parsing, and
 * relocation processing. Additionally included are the screen and serial
 * output functions and related debugging support functions.
 *
 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
 * puts by Nick Holloway 1993, better puts by Martin Mares 1995
 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
 */

#include "misc.h"
#include "../string.h"

/*
 * WARNING!!
 * This code is compiled with -fPIC and it is relocated dynamically at
 * run time, but no relocation processing is performed. This means that
 * it is not safe to place pointers in static structures.
 */

/* Macros used by the included decompressor code below. */
#define STATIC		static

/*
 * Use normal definitions of mem*() from string.c. There are already
 * included header files which expect a definition of memset() and by
 * the time we define memset macro, it is too late.
 */
#undef memcpy
#undef memset
#define memzero(s, n)	memset((s), 0, (n))

/* Functions used by the included decompressor code below. */
static void error(char *m);

/*
 * This is set up by the setup-routine at boot-time
 */
struct boot_params *boot_params;

memptr free_mem_ptr;
memptr free_mem_end_ptr;

static char *vidmem;
static int vidport;
static int lines, cols;

#ifdef CONFIG_KERNEL_GZIP
#include "../../../../lib/decompress_inflate.c"
#endif

#ifdef CONFIG_KERNEL_BZIP2
#include "../../../../lib/decompress_bunzip2.c"
#endif

#ifdef CONFIG_KERNEL_LZMA
#include "../../../../lib/decompress_unlzma.c"
#endif

#ifdef CONFIG_KERNEL_XZ
#include "../../../../lib/decompress_unxz.c"
#endif

#ifdef CONFIG_KERNEL_LZO
#include "../../../../lib/decompress_unlzo.c"
#endif

#ifdef CONFIG_KERNEL_LZ4
#include "../../../../lib/decompress_unlz4.c"
#endif
/*
 * NOTE: When adding a new decompressor, please update the analysis in
 * ../header.S.
 */

static void scroll(void)
{
	int i;

	memcpy(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2);
	for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2)
		vidmem[i] = ' ';
}

#define XMTRDY          0x20

#define TXR             0       /*  Transmit register (WRITE) */
#define LSR             5       /*  Line Status               */
static void serial_putchar(int ch)
{
	unsigned timeout = 0xffff;

	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
		cpu_relax();

	outb(ch, early_serial_base + TXR);
}

void __putstr(const char *s)
{
	int x, y, pos;
	char c;

	if (early_serial_base) {
		const char *str = s;
		while (*str) {
			if (*str == '\n')
				serial_putchar('\r');
			serial_putchar(*str++);
		}
	}

	if (boot_params->screen_info.orig_video_mode == 0 &&
	    lines == 0 && cols == 0)
		return;

	x = boot_params->screen_info.orig_x;
	y = boot_params->screen_info.orig_y;

	while ((c = *s++) != '\0') {
		if (c == '\n') {
			x = 0;
			if (++y >= lines) {
				scroll();
				y--;
			}
		} else {
			vidmem[(x + cols * y) * 2] = c;
			if (++x >= cols) {
				x = 0;
				if (++y >= lines) {
					scroll();
					y--;
				}
			}
		}
	}

	boot_params->screen_info.orig_x = x;
	boot_params->screen_info.orig_y = y;

	pos = (x + cols * y) * 2;	/* Update cursor position */
	outb(14, vidport);
	outb(0xff & (pos >> 9), vidport+1);
	outb(15, vidport);
	outb(0xff & (pos >> 1), vidport+1);
}

void __puthex(unsigned long value)
{
	char alpha[2] = "0";
	int bits;

	for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) {
		unsigned long digit = (value >> bits) & 0xf;

		if (digit < 0xA)
			alpha[0] = '0' + digit;
		else
			alpha[0] = 'a' + (digit - 0xA);

		__putstr(alpha);
	}
}

static void error(char *x)
{
	error_putstr("\n\n");
	error_putstr(x);
	error_putstr("\n\n -- System halted");

	while (1)
		asm("hlt");
}

#if CONFIG_X86_NEED_RELOCS
static void handle_relocations(void *output, unsigned long output_len)
{
	int *reloc;
	unsigned long delta, map, ptr;
	unsigned long min_addr = (unsigned long)output;
	unsigned long max_addr = min_addr + output_len;

	/*
	 * Calculate the delta between where vmlinux was linked to load
	 * and where it was actually loaded.
	 */
	delta = min_addr - LOAD_PHYSICAL_ADDR;
	if (!delta) {
		debug_putstr("No relocation needed... ");
		return;
	}
	debug_putstr("Performing relocations... ");

	/*
	 * The kernel contains a table of relocation addresses. Those
	 * addresses have the final load address of the kernel in virtual
	 * memory. We are currently working in the self map. So we need to
	 * create an adjustment for kernel memory addresses to the self map.
	 * This will involve subtracting out the base address of the kernel.
	 */
	map = delta - __START_KERNEL_map;

	/*
	 * Process relocations: 32 bit relocations first then 64 bit after.
	 * Three sets of binary relocations are added to the end of the kernel
	 * before compression. Each relocation table entry is the kernel
	 * address of the location which needs to be updated stored as a
	 * 32-bit value which is sign extended to 64 bits.
	 *
	 * Format is:
	 *
	 * kernel bits...
	 * 0 - zero terminator for 64 bit relocations
	 * 64 bit relocation repeated
	 * 0 - zero terminator for inverse 32 bit relocations
	 * 32 bit inverse relocation repeated
	 * 0 - zero terminator for 32 bit relocations
	 * 32 bit relocation repeated
	 *
	 * So we work backwards from the end of the decompressed image.
	 */
	for (reloc = output + output_len - sizeof(*reloc); *reloc; reloc--) {
		int extended = *reloc;
		extended += map;

		ptr = (unsigned long)extended;
		if (ptr < min_addr || ptr > max_addr)
			error("32-bit relocation outside of kernel!\n");

		*(uint32_t *)ptr += delta;
	}
#ifdef CONFIG_X86_64
	while (*--reloc) {
		long extended = *reloc;
		extended += map;

		ptr = (unsigned long)extended;
		if (ptr < min_addr || ptr > max_addr)
			error("inverse 32-bit relocation outside of kernel!\n");

		*(int32_t *)ptr -= delta;
	}
	for (reloc--; *reloc; reloc--) {
		long extended = *reloc;
		extended += map;

		ptr = (unsigned long)extended;
		if (ptr < min_addr || ptr > max_addr)
			error("64-bit relocation outside of kernel!\n");

		*(uint64_t *)ptr += delta;
	}
#endif
}
#else
static inline void handle_relocations(void *output, unsigned long output_len)
{ }
#endif

static void parse_elf(void *output)
{
#ifdef CONFIG_X86_64
	Elf64_Ehdr ehdr;
	Elf64_Phdr *phdrs, *phdr;
#else
	Elf32_Ehdr ehdr;
	Elf32_Phdr *phdrs, *phdr;
#endif
	void *dest;
	int i;

	memcpy(&ehdr, output, sizeof(ehdr));
	if (ehdr.e_ident[EI_MAG0] != ELFMAG0 ||
	   ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
	   ehdr.e_ident[EI_MAG2] != ELFMAG2 ||
	   ehdr.e_ident[EI_MAG3] != ELFMAG3) {
		error("Kernel is not a valid ELF file");
		return;
	}

	debug_putstr("Parsing ELF... ");

	phdrs = malloc(sizeof(*phdrs) * ehdr.e_phnum);
	if (!phdrs)
		error("Failed to allocate space for phdrs");

	memcpy(phdrs, output + ehdr.e_phoff, sizeof(*phdrs) * ehdr.e_phnum);

	for (i = 0; i < ehdr.e_phnum; i++) {
		phdr = &phdrs[i];

		switch (phdr->p_type) {
		case PT_LOAD:
#ifdef CONFIG_RELOCATABLE
			dest = output;
			dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR);
#else
			dest = (void *)(phdr->p_paddr);
#endif
			memcpy(dest,
			       output + phdr->p_offset,
			       phdr->p_filesz);
			break;
		default: /* Ignore other PT_* */ break;
		}
	}

	free(phdrs);
}

asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
				  unsigned char *input_data,
				  unsigned long input_len,
				  unsigned char *output,
				  unsigned long output_len,
				  unsigned long run_size)
{
	unsigned char *output_orig = output;

	/* Retain x86 boot parameters pointer passed from startup_32/64. */
	boot_params = rmode;

	/* Clear flags intended for solely in-kernel use. */
	boot_params->hdr.loadflags &= ~KASLR_FLAG;

	sanitize_boot_params(boot_params);

	if (boot_params->screen_info.orig_video_mode == 7) {
		vidmem = (char *) 0xb0000;
		vidport = 0x3b4;
	} else {
		vidmem = (char *) 0xb8000;
		vidport = 0x3d4;
	}

	lines = boot_params->screen_info.orig_video_lines;
	cols = boot_params->screen_info.orig_video_cols;

	console_init();
	debug_putstr("early console in extract_kernel\n");

	free_mem_ptr     = heap;	/* Heap */
	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;

	/* Report initial kernel position details. */
	debug_putaddr(input_data);
	debug_putaddr(input_len);
	debug_putaddr(output);
	debug_putaddr(output_len);
	debug_putaddr(run_size);

	/*
	 * The memory hole needed for the kernel is the larger of either
	 * the entire decompressed kernel plus relocation table, or the
	 * entire decompressed kernel plus .bss and .brk sections.
	 */
	output = choose_random_location(input_data, input_len, output,
					output_len > run_size ? output_len
							      : run_size);

	/* Validate memory location choices. */
	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
		error("Destination address inappropriately aligned");
#ifdef CONFIG_X86_64
	if (heap > 0x3fffffffffffUL)
		error("Destination address too large");
#else
	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
		error("Destination address too large");
#endif
#ifndef CONFIG_RELOCATABLE
	if ((unsigned long)output != LOAD_PHYSICAL_ADDR)
		error("Wrong destination address");
#endif

	debug_putstr("\nDecompressing Linux... ");
	__decompress(input_data, input_len, NULL, NULL, output, output_len,
			NULL, error);
	parse_elf(output);
	/*
	 * 32-bit always performs relocations. 64-bit relocations are only
	 * needed if kASLR has chosen a different load address.
	 */
	if (!IS_ENABLED(CONFIG_X86_64) || output != output_orig)
		handle_relocations(output, output_len);
	debug_putstr("done.\nBooting the kernel.\n");
	return output;
}
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* misc.c
818a08f8	3	*
c0402881 KC	4	* This is a collection of several routines used to extract the kernel
	5	* which includes KASLR relocation, decompression, ELF parsing, and
	6	* relocation processing. Additionally included are the screen and serial
	7	* output functions and related debugging support functions.
1da177e4 LT	8	*
	9	* malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
	10	* puts by Nick Holloway 1993, better puts by Martin Mares 1995
	11	* High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
	12	*/
	13
8fee13a4	14	#include "misc.h"
820e8fec	15	#include "../string.h"
968de4f0	16
968de4f0	17	/*
4252db10 BH	18	* WARNING!!
	19	* This code is compiled with -fPIC and it is relocated dynamically at
	20	* run time, but no relocation processing is performed. This means that
	21	* it is not safe to place pointers in static structures.
968de4f0	22	*/
1da177e4	23
1f208de3	24	/* Macros used by the included decompressor code below. */
1180e01d	25	#define STATIC static
1da177e4	26
04999550	27	/*
1f208de3	28	* Use normal definitions of mem*() from string.c. There are already
04999550 VG	29	* included header files which expect a definition of memset() and by
	30	* the time we define memset macro, it is too late.
	31	*/
1f208de3	32	#undef memcpy
04999550	33	#undef memset
1180e01d	34	#define memzero(s, n) memset((s), 0, (n))
1da177e4	35
1f208de3	36	/* Functions used by the included decompressor code below. */
1da177e4	37	static void error(char *m);
fd77c7ca	38
1da177e4 LT	39	/*
	40	* This is set up by the setup-routine at boot-time
	41	*/
6655e0aa	42	struct boot_params *boot_params;
1da177e4	43
82fa9637 KC	44	memptr free_mem_ptr;
82fa9637 KC	45	memptr free_mem_end_ptr;
1da177e4	46
03056c88	47	static char *vidmem;
1da177e4 LT	48	static int vidport;
	49	static int lines, cols;
	50
ae03c499 AK	51	#ifdef CONFIG_KERNEL_GZIP
	52	#include "../../../../lib/decompress_inflate.c"
	53	#endif
	54
	55	#ifdef CONFIG_KERNEL_BZIP2
	56	#include "../../../../lib/decompress_bunzip2.c"
	57	#endif
	58
	59	#ifdef CONFIG_KERNEL_LZMA
	60	#include "../../../../lib/decompress_unlzma.c"
	61	#endif
1da177e4	62
30314804 LC	63	#ifdef CONFIG_KERNEL_XZ
	64	#include "../../../../lib/decompress_unxz.c"
	65	#endif
	66
13510997 AT	67	#ifdef CONFIG_KERNEL_LZO
	68	#include "../../../../lib/decompress_unlzo.c"
	69	#endif
	70
f9b493ac KL	71	#ifdef CONFIG_KERNEL_LZ4
	72	#include "../../../../lib/decompress_unlz4.c"
	73	#endif
4252db10 BH	74	/*
	75	* NOTE: When adding a new decompressor, please update the analysis in
	76	* ../header.S.
	77	*/
f9b493ac	78
1da177e4 LT	79	static void scroll(void)
	80	{
	81	int i;
	82
fd77c7ca PC	83	memcpy(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2);
fd77c7ca PC	84	for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2)
1da177e4 LT	85	vidmem[i] = ' ';
	86	}
	87
8fee13a4 YL	88	#define XMTRDY 0x20
	89
	90	#define TXR 0 /* Transmit register (WRITE) */
	91	#define LSR 5 /* Line Status */
	92	static void serial_putchar(int ch)
	93	{
	94	unsigned timeout = 0xffff;
	95
	96	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
	97	cpu_relax();
	98
	99	outb(ch, early_serial_base + TXR);
	100	}
	101
7aac3015	102	void __putstr(const char *s)
1da177e4	103	{
fd77c7ca	104	int x, y, pos;
1da177e4 LT	105	char c;
1da177e4 LT	106
8fee13a4 YL	107	if (early_serial_base) {
	108	const char *str = s;
	109	while (*str) {
	110	if (*str == '\n')
	111	serial_putchar('\r');
	112	serial_putchar(*str++);
	113	}
	114	}
6bcb13b3	115
6655e0aa	116	if (boot_params->screen_info.orig_video_mode == 0 &&
23968f71	117	lines == 0 && cols == 0)
a24e7851 RR	118	return;
a24e7851 RR	119
6655e0aa KC	120	x = boot_params->screen_info.orig_x;
6655e0aa KC	121	y = boot_params->screen_info.orig_y;
1da177e4	122
fd77c7ca PC	123	while ((c = *s++) != '\0') {
fd77c7ca PC	124	if (c == '\n') {
1da177e4	125	x = 0;
fd77c7ca	126	if (++y >= lines) {
1da177e4 LT	127	scroll();
	128	y--;
	129	}
	130	} else {
020878ac	131	vidmem[(x + cols * y) * 2] = c;
fd77c7ca	132	if (++x >= cols) {
1da177e4	133	x = 0;
fd77c7ca	134	if (++y >= lines) {
1da177e4 LT	135	scroll();
	136	y--;
	137	}
	138	}
	139	}
	140	}
	141
6655e0aa KC	142	boot_params->screen_info.orig_x = x;
6655e0aa KC	143	boot_params->screen_info.orig_y = y;
1da177e4 LT	144
1da177e4 LT	145	pos = (x + cols * y) * 2; /* Update cursor position */
b02aae9c RH	146	outb(14, vidport);
	147	outb(0xff & (pos >> 9), vidport+1);
	148	outb(15, vidport);
	149	outb(0xff & (pos >> 1), vidport+1);
1da177e4 LT	150	}
1da177e4 LT	151
79063a7c KC	152	void __puthex(unsigned long value)
	153	{
	154	char alpha[2] = "0";
	155	int bits;
	156
	157	for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) {
	158	unsigned long digit = (value >> bits) & 0xf;
	159
	160	if (digit < 0xA)
	161	alpha[0] = '0' + digit;
	162	else
	163	alpha[0] = 'a' + (digit - 0xA);
	164
	165	__putstr(alpha);
	166	}
	167	}
	168
1da177e4 LT	169	static void error(char *x)
1da177e4 LT	170	{
cb454fe1 JM	171	error_putstr("\n\n");
	172	error_putstr(x);
	173	error_putstr("\n\n -- System halted");
1da177e4	174
ff3cf856 IM	175	while (1)
ff3cf856 IM	176	asm("hlt");
1da177e4 LT	177	}
1da177e4 LT	178
a0215061 KC	179	#if CONFIG_X86_NEED_RELOCS
	180	static void handle_relocations(void *output, unsigned long output_len)
	181	{
	182	int *reloc;
	183	unsigned long delta, map, ptr;
	184	unsigned long min_addr = (unsigned long)output;
	185	unsigned long max_addr = min_addr + output_len;
	186
	187	/*
	188	* Calculate the delta between where vmlinux was linked to load
	189	* and where it was actually loaded.
	190	*/
	191	delta = min_addr - LOAD_PHYSICAL_ADDR;
	192	if (!delta) {
	193	debug_putstr("No relocation needed... ");
	194	return;
	195	}
	196	debug_putstr("Performing relocations... ");
	197
	198	/*
	199	* The kernel contains a table of relocation addresses. Those
	200	* addresses have the final load address of the kernel in virtual
	201	* memory. We are currently working in the self map. So we need to
	202	* create an adjustment for kernel memory addresses to the self map.
	203	* This will involve subtracting out the base address of the kernel.
	204	*/
	205	map = delta - __START_KERNEL_map;
	206
	207	/*
	208	* Process relocations: 32 bit relocations first then 64 bit after.
6d24c5f7	209	* Three sets of binary relocations are added to the end of the kernel
a0215061 KC	210	* before compression. Each relocation table entry is the kernel
	211	* address of the location which needs to be updated stored as a
	212	* 32-bit value which is sign extended to 64 bits.
	213	*
	214	* Format is:
	215	*
	216	* kernel bits...
	217	* 0 - zero terminator for 64 bit relocations
	218	* 64 bit relocation repeated
6d24c5f7 JB	219	* 0 - zero terminator for inverse 32 bit relocations
6d24c5f7 JB	220	* 32 bit inverse relocation repeated
a0215061 KC	221	* 0 - zero terminator for 32 bit relocations
	222	* 32 bit relocation repeated
	223	*
	224	* So we work backwards from the end of the decompressed image.
	225	*/
	226	for (reloc = output + output_len - sizeof(reloc); reloc; reloc--) {
	227	int extended = *reloc;
	228	extended += map;
	229
	230	ptr = (unsigned long)extended;
	231	if (ptr < min_addr \|\| ptr > max_addr)
	232	error("32-bit relocation outside of kernel!\n");
	233
	234	(uint32_t )ptr += delta;
	235	}
	236	#ifdef CONFIG_X86_64
6d24c5f7 JB	237	while (*--reloc) {
	238	long extended = *reloc;
	239	extended += map;
	240
	241	ptr = (unsigned long)extended;
	242	if (ptr < min_addr \|\| ptr > max_addr)
	243	error("inverse 32-bit relocation outside of kernel!\n");
	244
	245	(int32_t )ptr -= delta;
	246	}
a0215061 KC	247	for (reloc--; *reloc; reloc--) {
	248	long extended = *reloc;
	249	extended += map;
	250
	251	ptr = (unsigned long)extended;
	252	if (ptr < min_addr \|\| ptr > max_addr)
	253	error("64-bit relocation outside of kernel!\n");
	254
	255	(uint64_t )ptr += delta;
	256	}
	257	#endif
	258	}
	259	#else
	260	static inline void handle_relocations(void *output, unsigned long output_len)
	261	{ }
	262	#endif
	263
099e1377 IC	264	static void parse_elf(void *output)
	265	{
	266	#ifdef CONFIG_X86_64
	267	Elf64_Ehdr ehdr;
	268	Elf64_Phdr phdrs, phdr;
	269	#else
	270	Elf32_Ehdr ehdr;
	271	Elf32_Phdr phdrs, phdr;
	272	#endif
	273	void *dest;
	274	int i;
	275
	276	memcpy(&ehdr, output, sizeof(ehdr));
fd77c7ca	277	if (ehdr.e_ident[EI_MAG0] != ELFMAG0 \|\|
099e1377 IC	278	ehdr.e_ident[EI_MAG1] != ELFMAG1 \|\|
099e1377 IC	279	ehdr.e_ident[EI_MAG2] != ELFMAG2 \|\|
fd77c7ca	280	ehdr.e_ident[EI_MAG3] != ELFMAG3) {
099e1377 IC	281	error("Kernel is not a valid ELF file");
	282	return;
	283	}
	284
e605a425	285	debug_putstr("Parsing ELF... ");
099e1377 IC	286
	287	phdrs = malloc(sizeof(phdrs) ehdr.e_phnum);
	288	if (!phdrs)
	289	error("Failed to allocate space for phdrs");
	290
	291	memcpy(phdrs, output + ehdr.e_phoff, sizeof(phdrs) ehdr.e_phnum);
	292
fd77c7ca	293	for (i = 0; i < ehdr.e_phnum; i++) {
099e1377 IC	294	phdr = &phdrs[i];
	295
	296	switch (phdr->p_type) {
	297	case PT_LOAD:
	298	#ifdef CONFIG_RELOCATABLE
	299	dest = output;
	300	dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR);
	301	#else
fd77c7ca	302	dest = (void *)(phdr->p_paddr);
099e1377 IC	303	#endif
	304	memcpy(dest,
	305	output + phdr->p_offset,
	306	phdr->p_filesz);
	307	break;
	308	default: /* Ignore other PT_* */ break;
	309	}
	310	}
5067cf53 JJ	311
5067cf53 JJ	312	free(phdrs);
099e1377 IC	313	}
099e1377 IC	314
c0402881	315	asmlinkage __visible void extract_kernel(void rmode, memptr heap,
1180e01d IM	316	unsigned char *input_data,
1180e01d IM	317	unsigned long input_len,
a0215061	318	unsigned char *output,
e6023367 JM	319	unsigned long output_len,
e6023367 JM	320	unsigned long run_size)
1da177e4	321	{
f285f4a2 KC	322	unsigned char *output_orig = output;
f285f4a2 KC	323
6655e0aa KC	324	/* Retain x86 boot parameters pointer passed from startup_32/64. */
6655e0aa KC	325	boot_params = rmode;
1da177e4	326
6655e0aa KC	327	/* Clear flags intended for solely in-kernel use. */
6655e0aa KC	328	boot_params->hdr.loadflags &= ~KASLR_FLAG;
78cac48c	329
6655e0aa	330	sanitize_boot_params(boot_params);
5dcd14ec	331
6655e0aa	332	if (boot_params->screen_info.orig_video_mode == 7) {
1da177e4 LT	333	vidmem = (char *) 0xb0000;
	334	vidport = 0x3b4;
	335	} else {
	336	vidmem = (char *) 0xb8000;
	337	vidport = 0x3d4;
	338	}
	339
6655e0aa KC	340	lines = boot_params->screen_info.orig_video_lines;
6655e0aa KC	341	cols = boot_params->screen_info.orig_video_cols;
1da177e4	342
8fee13a4	343	console_init();
c0402881	344	debug_putstr("early console in extract_kernel\n");
8fee13a4	345
4c83d653	346	free_mem_ptr = heap; /* Heap */
7c539764	347	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
968de4f0	348
79063a7c KC	349	/* Report initial kernel position details. */
	350	debug_putaddr(input_data);
	351	debug_putaddr(input_len);
	352	debug_putaddr(output);
	353	debug_putaddr(output_len);
	354	debug_putaddr(run_size);
	355
e6023367 JM	356	/*
	357	* The memory hole needed for the kernel is the larger of either
	358	* the entire decompressed kernel plus relocation table, or the
	359	* entire decompressed kernel plus .bss and .brk sections.
	360	*/
7de828df	361	output = choose_random_location(input_data, input_len, output,
e6023367 JM	362	output_len > run_size ? output_len
e6023367 JM	363	: run_size);
8ab3820f KC	364
8ab3820f KC	365	/* Validate memory location choices. */
7ed42a28 PA	366	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
7ed42a28 PA	367	error("Destination address inappropriately aligned");
778cb929	368	#ifdef CONFIG_X86_64
7ed42a28	369	if (heap > 0x3fffffffffffUL)
778cb929 IC	370	error("Destination address too large");
778cb929 IC	371	#else
147dd561	372	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
968de4f0	373	error("Destination address too large");
7ed42a28	374	#endif
968de4f0	375	#ifndef CONFIG_RELOCATABLE
7ed42a28	376	if ((unsigned long)output != LOAD_PHYSICAL_ADDR)
968de4f0 EB	377	error("Wrong destination address");
968de4f0 EB	378	#endif
1da177e4	379
e605a425	380	debug_putstr("\nDecompressing Linux... ");
2d3862d2 YL	381	__decompress(input_data, input_len, NULL, NULL, output, output_len,
2d3862d2 YL	382	NULL, error);
099e1377	383	parse_elf(output);
f285f4a2 KC	384	/*
	385	* 32-bit always performs relocations. 64-bit relocations are only
	386	* needed if kASLR has chosen a different load address.
	387	*/
	388	if (!IS_ENABLED(CONFIG_X86_64) \|\| output != output_orig)
	389	handle_relocations(output, output_len);
e605a425	390	debug_putstr("done.\nBooting the kernel.\n");
8ab3820f	391	return output;
1da177e4	392	}