/* * 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; }