[linux-block.git] / arch / x86 / power / hibernate_64.c

/*
 * Hibernation support for x86-64
 *
 * Distribute under GPLv2
 *
 * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl>
 * Copyright (c) 2002 Pavel Machek <pavel@ucw.cz>
 * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
 */

#include <linux/gfp.h>
#include <linux/smp.h>
#include <linux/suspend.h>

#include <asm/init.h>
#include <asm/proto.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/mtrr.h>
#include <asm/sections.h>
#include <asm/suspend.h>

/* Defined in hibernate_asm_64.S */
extern asmlinkage __visible int restore_image(void);

/*
 * Address to jump to in the last phase of restore in order to get to the image
 * kernel's text (this value is passed in the image header).
 */
unsigned long restore_jump_address __visible;

/*
 * Value of the cr3 register from before the hibernation (this value is passed
 * in the image header).
 */
unsigned long restore_cr3 __visible;

pgd_t *temp_level4_pgt __visible;

void *relocated_restore_code __visible;

static void *alloc_pgt_page(void *context)
{
	return (void *)get_safe_page(GFP_ATOMIC);
}

static int set_up_temporary_mappings(void)
{
	struct x86_mapping_info info = {
		.alloc_pgt_page	= alloc_pgt_page,
		.pmd_flag	= __PAGE_KERNEL_LARGE_EXEC,
		.kernel_mapping = true,
	};
	unsigned long mstart, mend;
	int result;
	int i;

	temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC);
	if (!temp_level4_pgt)
		return -ENOMEM;

	/* It is safe to reuse the original kernel mapping */
	set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map),
		init_level4_pgt[pgd_index(__START_KERNEL_map)]);

	/* Set up the direct mapping from scratch */
	for (i = 0; i < nr_pfn_mapped; i++) {
		mstart = pfn_mapped[i].start << PAGE_SHIFT;
		mend   = pfn_mapped[i].end << PAGE_SHIFT;

		result = kernel_ident_mapping_init(&info, temp_level4_pgt,
						   mstart, mend);

		if (result)
			return result;
	}

	return 0;
}

int swsusp_arch_resume(void)
{
	int error;

	/* We have got enough memory and from now on we cannot recover */
	if ((error = set_up_temporary_mappings()))
		return error;

	relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC);
	if (!relocated_restore_code)
		return -ENOMEM;
	memcpy(relocated_restore_code, &core_restore_code,
	       &restore_registers - &core_restore_code);

	restore_image();
	return 0;
}

/*
 *	pfn_is_nosave - check if given pfn is in the 'nosave' section
 */

int pfn_is_nosave(unsigned long pfn)
{
	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
}

struct restore_data_record {
	unsigned long jump_address;
	unsigned long cr3;
	unsigned long magic;
};

#define RESTORE_MAGIC	0x0123456789ABCDEFUL

/**
 *	arch_hibernation_header_save - populate the architecture specific part
 *		of a hibernation image header
 *	@addr: address to save the data at
 */
int arch_hibernation_header_save(void *addr, unsigned int max_size)
{
	struct restore_data_record *rdr = addr;

	if (max_size < sizeof(struct restore_data_record))
		return -EOVERFLOW;
	rdr->jump_address = restore_jump_address;
	rdr->cr3 = restore_cr3;
	rdr->magic = RESTORE_MAGIC;
	return 0;
}

/**
 *	arch_hibernation_header_restore - read the architecture specific data
 *		from the hibernation image header
 *	@addr: address to read the data from
 */
int arch_hibernation_header_restore(void *addr)
{
	struct restore_data_record *rdr = addr;

	restore_jump_address = rdr->jump_address;
	restore_cr3 = rdr->cr3;
	return (rdr->magic == RESTORE_MAGIC) ? 0 : -EINVAL;
}
Commit	Line	Data
ef8b03fa RW	1	/*
	2	* Hibernation support for x86-64
	3	*
	4	* Distribute under GPLv2
	5	*
	6	* Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl>
a2531293	7	* Copyright (c) 2002 Pavel Machek <pavel@ucw.cz>
ef8b03fa RW	8	* Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
	9	*/
	10
5a0e3ad6	11	#include <linux/gfp.h>
ef8b03fa RW	12	#include <linux/smp.h>
ef8b03fa RW	13	#include <linux/suspend.h>
8b78c21d YL	14
8b78c21d YL	15	#include <asm/init.h>
ef8b03fa RW	16	#include <asm/proto.h>
	17	#include <asm/page.h>
	18	#include <asm/pgtable.h>
	19	#include <asm/mtrr.h>
7f8998c7	20	#include <asm/sections.h>
a8af7898	21	#include <asm/suspend.h>
ef8b03fa	22
261f0ce5	23	/* Defined in hibernate_asm_64.S */
2605fc21	24	extern asmlinkage __visible int restore_image(void);
ef8b03fa RW	25
	26	/*
	27	* Address to jump to in the last phase of restore in order to get to the image
	28	* kernel's text (this value is passed in the image header).
	29	*/
d6efc2f7	30	unsigned long restore_jump_address __visible;
ef8b03fa RW	31
	32	/*
	33	* Value of the cr3 register from before the hibernation (this value is passed
	34	* in the image header).
	35	*/
d6efc2f7	36	unsigned long restore_cr3 __visible;
ef8b03fa	37
d6efc2f7	38	pgd_t *temp_level4_pgt __visible;
ef8b03fa	39
d6efc2f7	40	void *relocated_restore_code __visible;
ef8b03fa	41
8b78c21d	42	static void alloc_pgt_page(void context)
ef8b03fa	43	{
8b78c21d	44	return (void *)get_safe_page(GFP_ATOMIC);
ef8b03fa RW	45	}
	46
	47	static int set_up_temporary_mappings(void)
	48	{
8b78c21d YL	49	struct x86_mapping_info info = {
	50	.alloc_pgt_page = alloc_pgt_page,
	51	.pmd_flag = __PAGE_KERNEL_LARGE_EXEC,
	52	.kernel_mapping = true,
	53	};
	54	unsigned long mstart, mend;
	55	int result;
	56	int i;
ef8b03fa RW	57
	58	temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC);
	59	if (!temp_level4_pgt)
	60	return -ENOMEM;
	61
	62	/* It is safe to reuse the original kernel mapping */
	63	set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map),
	64	init_level4_pgt[pgd_index(__START_KERNEL_map)]);
	65
	66	/* Set up the direct mapping from scratch */
8b78c21d YL	67	for (i = 0; i < nr_pfn_mapped; i++) {
	68	mstart = pfn_mapped[i].start << PAGE_SHIFT;
	69	mend = pfn_mapped[i].end << PAGE_SHIFT;
	70
	71	result = kernel_ident_mapping_init(&info, temp_level4_pgt,
	72	mstart, mend);
	73
	74	if (result)
	75	return result;
ef8b03fa	76	}
8b78c21d	77
ef8b03fa RW	78	return 0;
	79	}
	80
	81	int swsusp_arch_resume(void)
	82	{
	83	int error;
	84
	85	/* We have got enough memory and from now on we cannot recover */
	86	if ((error = set_up_temporary_mappings()))
	87	return error;
	88
	89	relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC);
	90	if (!relocated_restore_code)
	91	return -ENOMEM;
	92	memcpy(relocated_restore_code, &core_restore_code,
	93	&restore_registers - &core_restore_code);
	94
	95	restore_image();
	96	return 0;
	97	}
	98
	99	/*
	100	* pfn_is_nosave - check if given pfn is in the 'nosave' section
	101	*/
	102
	103	int pfn_is_nosave(unsigned long pfn)
	104	{
	105	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
	106	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
	107	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
	108	}
	109
	110	struct restore_data_record {
	111	unsigned long jump_address;
	112	unsigned long cr3;
	113	unsigned long magic;
	114	};
	115
	116	#define RESTORE_MAGIC 0x0123456789ABCDEFUL
	117
	118	/**
	119	* arch_hibernation_header_save - populate the architecture specific part
	120	* of a hibernation image header
	121	* @addr: address to save the data at
	122	*/
	123	int arch_hibernation_header_save(void *addr, unsigned int max_size)
	124	{
	125	struct restore_data_record *rdr = addr;
	126
	127	if (max_size < sizeof(struct restore_data_record))
	128	return -EOVERFLOW;
	129	rdr->jump_address = restore_jump_address;
	130	rdr->cr3 = restore_cr3;
	131	rdr->magic = RESTORE_MAGIC;
	132	return 0;
	133	}
	134
	135	/**
	136	* arch_hibernation_header_restore - read the architecture specific data
	137	* from the hibernation image header
	138	* @addr: address to read the data from
	139	*/
	140	int arch_hibernation_header_restore(void *addr)
	141	{
142	struct restore_data_record *rdr = addr;
143
144	restore_jump_address = rdr->jump_address;
145	restore_cr3 = rdr->cr3;
146	return (rdr->magic == RESTORE_MAGIC) ? 0 : -EINVAL;
147	}