171 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			171 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Hibernation support for x86-64
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|  *
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|  * Distribute under GPLv2
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|  *
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|  * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl>
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|  * Copyright (c) 2002 Pavel Machek <pavel@suse.cz>
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|  * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
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|  */
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| 
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| #include <linux/smp.h>
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| #include <linux/suspend.h>
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| #include <asm/proto.h>
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| #include <asm/page.h>
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| #include <asm/pgtable.h>
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| #include <asm/mtrr.h>
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| #include <asm/suspend.h>
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| 
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| /* References to section boundaries */
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| extern const void __nosave_begin, __nosave_end;
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| 
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| /* Defined in hibernate_asm_64.S */
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| extern int restore_image(void);
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| 
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| /*
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|  * Address to jump to in the last phase of restore in order to get to the image
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|  * kernel's text (this value is passed in the image header).
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|  */
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| unsigned long restore_jump_address;
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| 
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| /*
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|  * Value of the cr3 register from before the hibernation (this value is passed
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|  * in the image header).
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|  */
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| unsigned long restore_cr3;
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| 
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| pgd_t *temp_level4_pgt;
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| 
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| void *relocated_restore_code;
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| 
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| static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end)
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| {
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| 	long i, j;
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| 
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| 	i = pud_index(address);
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| 	pud = pud + i;
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| 	for (; i < PTRS_PER_PUD; pud++, i++) {
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| 		unsigned long paddr;
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| 		pmd_t *pmd;
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| 
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| 		paddr = address + i*PUD_SIZE;
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| 		if (paddr >= end)
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| 			break;
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| 
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| 		pmd = (pmd_t *)get_safe_page(GFP_ATOMIC);
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| 		if (!pmd)
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| 			return -ENOMEM;
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| 		set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
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| 		for (j = 0; j < PTRS_PER_PMD; pmd++, j++, paddr += PMD_SIZE) {
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| 			unsigned long pe;
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| 
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| 			if (paddr >= end)
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| 				break;
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| 			pe = __PAGE_KERNEL_LARGE_EXEC | paddr;
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| 			pe &= __supported_pte_mask;
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| 			set_pmd(pmd, __pmd(pe));
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| 		}
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| 	}
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| 	return 0;
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| }
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| 
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| static int set_up_temporary_mappings(void)
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| {
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| 	unsigned long start, end, next;
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| 	int error;
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| 
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| 	temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC);
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| 	if (!temp_level4_pgt)
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| 		return -ENOMEM;
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| 
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| 	/* It is safe to reuse the original kernel mapping */
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| 	set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map),
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| 		init_level4_pgt[pgd_index(__START_KERNEL_map)]);
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| 
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| 	/* Set up the direct mapping from scratch */
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| 	start = (unsigned long)pfn_to_kaddr(0);
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| 	end = (unsigned long)pfn_to_kaddr(max_pfn);
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| 
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| 	for (; start < end; start = next) {
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| 		pud_t *pud = (pud_t *)get_safe_page(GFP_ATOMIC);
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| 		if (!pud)
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| 			return -ENOMEM;
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| 		next = start + PGDIR_SIZE;
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| 		if (next > end)
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| 			next = end;
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| 		if ((error = res_phys_pud_init(pud, __pa(start), __pa(next))))
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| 			return error;
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| 		set_pgd(temp_level4_pgt + pgd_index(start),
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| 			mk_kernel_pgd(__pa(pud)));
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| 	}
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| 	return 0;
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| }
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| 
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| int swsusp_arch_resume(void)
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| {
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| 	int error;
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| 
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| 	/* We have got enough memory and from now on we cannot recover */
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| 	if ((error = set_up_temporary_mappings()))
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| 		return error;
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| 
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| 	relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC);
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| 	if (!relocated_restore_code)
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| 		return -ENOMEM;
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| 	memcpy(relocated_restore_code, &core_restore_code,
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| 	       &restore_registers - &core_restore_code);
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| 
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| 	restore_image();
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| 	return 0;
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| }
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| 
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| /*
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|  *	pfn_is_nosave - check if given pfn is in the 'nosave' section
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|  */
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| 
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| int pfn_is_nosave(unsigned long pfn)
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| {
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| 	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
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| 	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
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| 	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
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| }
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| 
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| struct restore_data_record {
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| 	unsigned long jump_address;
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| 	unsigned long cr3;
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| 	unsigned long magic;
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| };
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| 
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| #define RESTORE_MAGIC	0x0123456789ABCDEFUL
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| 
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| /**
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|  *	arch_hibernation_header_save - populate the architecture specific part
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|  *		of a hibernation image header
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|  *	@addr: address to save the data at
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|  */
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| int arch_hibernation_header_save(void *addr, unsigned int max_size)
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| {
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| 	struct restore_data_record *rdr = addr;
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| 
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| 	if (max_size < sizeof(struct restore_data_record))
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| 		return -EOVERFLOW;
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| 	rdr->jump_address = restore_jump_address;
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| 	rdr->cr3 = restore_cr3;
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| 	rdr->magic = RESTORE_MAGIC;
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| 	return 0;
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| }
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| 
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| /**
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|  *	arch_hibernation_header_restore - read the architecture specific data
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|  *		from the hibernation image header
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|  *	@addr: address to read the data from
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|  */
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| int arch_hibernation_header_restore(void *addr)
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| {
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| 	struct restore_data_record *rdr = addr;
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| 
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| 	restore_jump_address = rdr->jump_address;
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| 	restore_cr3 = rdr->cr3;
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| 	return (rdr->magic == RESTORE_MAGIC) ? 0 : -EINVAL;
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| }
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