[linux-2.6-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 <linux/scatterlist.h>
#include <linux/kdebug.h>

#include <crypto/hash.h>

#include <asm/e820/api.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>
#include <asm/tlbflush.h>

static int set_up_temporary_text_mapping(pgd_t *pgd)
{
	pmd_t *pmd;
	pud_t *pud;
	p4d_t *p4d = NULL;
	pgprot_t pgtable_prot = __pgprot(_KERNPG_TABLE);
	pgprot_t pmd_text_prot = __pgprot(__PAGE_KERNEL_LARGE_EXEC);

	/* Filter out unsupported __PAGE_KERNEL* bits: */
	pgprot_val(pmd_text_prot) &= __default_kernel_pte_mask;
	pgprot_val(pgtable_prot)  &= __default_kernel_pte_mask;

	/*
	 * The new mapping only has to cover the page containing the image
	 * kernel's entry point (jump_address_phys), because the switch over to
	 * it is carried out by relocated code running from a page allocated
	 * specifically for this purpose and covered by the identity mapping, so
	 * the temporary kernel text mapping is only needed for the final jump.
	 * Moreover, in that mapping the virtual address of the image kernel's
	 * entry point must be the same as its virtual address in the image
	 * kernel (restore_jump_address), so the image kernel's
	 * restore_registers() code doesn't find itself in a different area of
	 * the virtual address space after switching over to the original page
	 * tables used by the image kernel.
	 */

	if (pgtable_l5_enabled()) {
		p4d = (p4d_t *)get_safe_page(GFP_ATOMIC);
		if (!p4d)
			return -ENOMEM;
	}

	pud = (pud_t *)get_safe_page(GFP_ATOMIC);
	if (!pud)
		return -ENOMEM;

	pmd = (pmd_t *)get_safe_page(GFP_ATOMIC);
	if (!pmd)
		return -ENOMEM;

	set_pmd(pmd + pmd_index(restore_jump_address),
		__pmd((jump_address_phys & PMD_MASK) | pgprot_val(pmd_text_prot)));
	set_pud(pud + pud_index(restore_jump_address),
		__pud(__pa(pmd) | pgprot_val(pgtable_prot)));
	if (p4d) {
		p4d_t new_p4d = __p4d(__pa(pud) | pgprot_val(pgtable_prot));
		pgd_t new_pgd = __pgd(__pa(p4d) | pgprot_val(pgtable_prot));

		set_p4d(p4d + p4d_index(restore_jump_address), new_p4d);
		set_pgd(pgd + pgd_index(restore_jump_address), new_pgd);
	} else {
		/* No p4d for 4-level paging: point the pgd to the pud page table */
		pgd_t new_pgd = __pgd(__pa(pud) | pgprot_val(pgtable_prot));
		set_pgd(pgd + pgd_index(restore_jump_address), new_pgd);
	}

	return 0;
}

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,
		.page_flag	= __PAGE_KERNEL_LARGE_EXEC,
		.offset		= __PAGE_OFFSET,
	};
	unsigned long mstart, mend;
	pgd_t *pgd;
	int result;
	int i;

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

	/* Prepare a temporary mapping for the kernel text */
	result = set_up_temporary_text_mapping(pgd);
	if (result)
		return result;

	/* 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, pgd, mstart, mend);
		if (result)
			return result;
	}

	temp_pgt = __pa(pgd);
	return 0;
}

asmlinkage int swsusp_arch_resume(void)
{
	int error;

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

	error = relocate_restore_code();
	if (error)
		return error;

	restore_image();
	return 0;
}
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>
62a03def CY	14	#include <linux/scatterlist.h>
	15	#include <linux/kdebug.h>
	16
	17	#include <crypto/hash.h>
8b78c21d	18
5520b7e7	19	#include <asm/e820/api.h>
8b78c21d	20	#include <asm/init.h>
ef8b03fa RW	21	#include <asm/proto.h>
	22	#include <asm/page.h>
	23	#include <asm/pgtable.h>
	24	#include <asm/mtrr.h>
7f8998c7	25	#include <asm/sections.h>
a8af7898	26	#include <asm/suspend.h>
65c0554b	27	#include <asm/tlbflush.h>
ef8b03fa	28
c226fab4	29	static int set_up_temporary_text_mapping(pgd_t *pgd)
65c0554b RW	30	{
	31	pmd_t *pmd;
	32	pud_t *pud;
91f606a8	33	p4d_t *p4d = NULL;
fb43d6cb DH	34	pgprot_t pgtable_prot = __pgprot(_KERNPG_TABLE);
	35	pgprot_t pmd_text_prot = __pgprot(__PAGE_KERNEL_LARGE_EXEC);
	36
	37	/* Filter out unsupported __PAGE_KERNEL* bits: */
	38	pgprot_val(pmd_text_prot) &= __default_kernel_pte_mask;
	39	pgprot_val(pgtable_prot) &= __default_kernel_pte_mask;
65c0554b RW	40
	41	/*
	42	* The new mapping only has to cover the page containing the image
	43	* kernel's entry point (jump_address_phys), because the switch over to
	44	* it is carried out by relocated code running from a page allocated
	45	* specifically for this purpose and covered by the identity mapping, so
	46	* the temporary kernel text mapping is only needed for the final jump.
	47	* Moreover, in that mapping the virtual address of the image kernel's
	48	* entry point must be the same as its virtual address in the image
	49	* kernel (restore_jump_address), so the image kernel's
	50	* restore_registers() code doesn't find itself in a different area of
	51	* the virtual address space after switching over to the original page
	52	* tables used by the image kernel.
	53	*/
06c830a4	54
ed7588d5	55	if (pgtable_l5_enabled()) {
06c830a4 KS	56	p4d = (p4d_t *)get_safe_page(GFP_ATOMIC);
	57	if (!p4d)
	58	return -ENOMEM;
	59	}
	60
65c0554b RW	61	pud = (pud_t *)get_safe_page(GFP_ATOMIC);
	62	if (!pud)
	63	return -ENOMEM;
	64
	65	pmd = (pmd_t *)get_safe_page(GFP_ATOMIC);
	66	if (!pmd)
	67	return -ENOMEM;
	68
	69	set_pmd(pmd + pmd_index(restore_jump_address),
fb43d6cb	70	__pmd((jump_address_phys & PMD_MASK) \| pgprot_val(pmd_text_prot)));
65c0554b	71	set_pud(pud + pud_index(restore_jump_address),
fb43d6cb	72	__pud(__pa(pmd) \| pgprot_val(pgtable_prot)));
91f606a8	73	if (p4d) {
fb43d6cb DH	74	p4d_t new_p4d = __p4d(__pa(pud) \| pgprot_val(pgtable_prot));
	75	pgd_t new_pgd = __pgd(__pa(p4d) \| pgprot_val(pgtable_prot));
	76
	77	set_p4d(p4d + p4d_index(restore_jump_address), new_p4d);
	78	set_pgd(pgd + pgd_index(restore_jump_address), new_pgd);
06c830a4 KS	79	} else {
06c830a4 KS	80	/* No p4d for 4-level paging: point the pgd to the pud page table */
05189820	81	pgd_t new_pgd = __pgd(__pa(pud) \| pgprot_val(pgtable_prot));
fb43d6cb	82	set_pgd(pgd + pgd_index(restore_jump_address), new_pgd);
06c830a4	83	}
65c0554b RW	84
	85	return 0;
	86	}
ef8b03fa	87
8b78c21d	88	static void alloc_pgt_page(void context)
ef8b03fa	89	{
8b78c21d	90	return (void *)get_safe_page(GFP_ATOMIC);
ef8b03fa RW	91	}
	92
	93	static int set_up_temporary_mappings(void)
	94	{
8b78c21d YL	95	struct x86_mapping_info info = {
8b78c21d YL	96	.alloc_pgt_page = alloc_pgt_page,
66aad4fd	97	.page_flag = __PAGE_KERNEL_LARGE_EXEC,
e4630fdd	98	.offset = __PAGE_OFFSET,
8b78c21d YL	99	};
8b78c21d YL	100	unsigned long mstart, mend;
c226fab4	101	pgd_t *pgd;
8b78c21d YL	102	int result;
8b78c21d YL	103	int i;
ef8b03fa	104
c226fab4 RW	105	pgd = (pgd_t *)get_safe_page(GFP_ATOMIC);
c226fab4 RW	106	if (!pgd)
ef8b03fa RW	107	return -ENOMEM;
ef8b03fa RW	108
65c0554b	109	/* Prepare a temporary mapping for the kernel text */
c226fab4	110	result = set_up_temporary_text_mapping(pgd);
65c0554b RW	111	if (result)
65c0554b RW	112	return result;
ef8b03fa RW	113
ef8b03fa RW	114	/* Set up the direct mapping from scratch */
8b78c21d YL	115	for (i = 0; i < nr_pfn_mapped; i++) {
	116	mstart = pfn_mapped[i].start << PAGE_SHIFT;
	117	mend = pfn_mapped[i].end << PAGE_SHIFT;
	118
c226fab4	119	result = kernel_ident_mapping_init(&info, pgd, mstart, mend);
8b78c21d YL	120	if (result)
8b78c21d YL	121	return result;
ef8b03fa	122	}
8b78c21d	123
72adf477	124	temp_pgt = __pa(pgd);
ef8b03fa RW	125	return 0;
	126	}
	127
328008a7	128	asmlinkage int swsusp_arch_resume(void)
ef8b03fa RW	129	{
	130	int error;
	131
	132	/* We have got enough memory and from now on we cannot recover */
65c0554b RW	133	error = set_up_temporary_mappings();
65c0554b RW	134	if (error)
ef8b03fa RW	135	return error;
ef8b03fa RW	136
65c0554b RW	137	error = relocate_restore_code();
	138	if (error)
	139	return error;
ef8b03fa RW	140
	141	restore_image();
	142	return 0;
	143	}