diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/suspend_64.c | 54 | ||||
| -rw-r--r-- | arch/x86/kernel/suspend_asm_64.S | 41 |
2 files changed, 87 insertions, 8 deletions
diff --git a/arch/x86/kernel/suspend_64.c b/arch/x86/kernel/suspend_64.c index 573c0a6e0ac..01fbfb018ca 100644 --- a/arch/x86/kernel/suspend_64.c +++ b/arch/x86/kernel/suspend_64.c @@ -150,8 +150,16 @@ void fix_processor_context(void) /* Defined in arch/x86_64/kernel/suspend_asm.S */ extern 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; + pgd_t *temp_level4_pgt; +void *relocated_restore_code; + static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end) { long i, j; @@ -175,7 +183,7 @@ static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long en if (paddr >= end) break; - pe = _PAGE_NX | _PAGE_PSE | _KERNPG_TABLE | paddr; + pe = __PAGE_KERNEL_LARGE_EXEC | paddr; pe &= __supported_pte_mask; set_pmd(pmd, __pmd(pe)); } @@ -222,6 +230,13 @@ int swsusp_arch_resume(void) /* 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; } @@ -236,4 +251,41 @@ int pfn_is_nosave(unsigned long pfn) 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 control; +}; + +#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->control = (restore_jump_address ^ 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; + return (rdr->control == (restore_jump_address ^ RESTORE_MAGIC)) ? + 0 : -EINVAL; +} #endif /* CONFIG_HIBERNATION */ diff --git a/arch/x86/kernel/suspend_asm_64.S b/arch/x86/kernel/suspend_asm_64.S index 16d183f67bc..40a209e0525 100644 --- a/arch/x86/kernel/suspend_asm_64.S +++ b/arch/x86/kernel/suspend_asm_64.S @@ -2,8 +2,8 @@ * * Distribute under GPLv2. * - * swsusp_arch_resume may not use any stack, nor any variable that is - * not "NoSave" during copying pages: + * swsusp_arch_resume must not use any stack or any nonlocal variables while + * copying pages: * * Its rewriting one kernel image with another. What is stack in "old" * image could very well be data page in "new" image, and overwriting @@ -36,6 +36,10 @@ ENTRY(swsusp_arch_suspend) movq %r15, saved_context_r15(%rip) pushfq ; popq saved_context_eflags(%rip) + /* save the address of restore_registers */ + movq $restore_registers, %rax + movq %rax, restore_jump_address(%rip) + call swsusp_save ret @@ -54,7 +58,16 @@ ENTRY(restore_image) movq %rcx, %cr3; movq %rax, %cr4; # turn PGE back on + /* prepare to jump to the image kernel */ + movq restore_jump_address(%rip), %rax + + /* prepare to copy image data to their original locations */ movq restore_pblist(%rip), %rdx + movq relocated_restore_code(%rip), %rcx + jmpq *%rcx + + /* code below has been relocated to a safe page */ +ENTRY(core_restore_code) loop: testq %rdx, %rdx jz done @@ -62,7 +75,7 @@ loop: /* get addresses from the pbe and copy the page */ movq pbe_address(%rdx), %rsi movq pbe_orig_address(%rdx), %rdi - movq $512, %rcx + movq $(PAGE_SIZE >> 3), %rcx rep movsq @@ -70,6 +83,20 @@ loop: movq pbe_next(%rdx), %rdx jmp loop done: + /* jump to the restore_registers address from the image header */ + jmpq *%rax + /* + * NOTE: This assumes that the boot kernel's text mapping covers the + * image kernel's page containing restore_registers and the address of + * this page is the same as in the image kernel's text mapping (it + * should always be true, because the text mapping is linear, starting + * from 0, and is supposed to cover the entire kernel text for every + * kernel). + * + * code below belongs to the image kernel + */ + +ENTRY(restore_registers) /* go back to the original page tables */ movq $(init_level4_pgt - __START_KERNEL_map), %rax addq phys_base(%rip), %rax @@ -84,12 +111,9 @@ done: movq %rcx, %cr3 movq %rax, %cr4; # turn PGE back on - movl $24, %eax - movl %eax, %ds - movq saved_context_esp(%rip), %rsp movq saved_context_ebp(%rip), %rbp - /* Don't restore %rax, it must be 0 anyway */ + /* restore GPRs (we don't restore %rax, it must be 0 anyway) */ movq saved_context_ebx(%rip), %rbx movq saved_context_ecx(%rip), %rcx movq saved_context_edx(%rip), %rdx @@ -107,4 +131,7 @@ done: xorq %rax, %rax + /* tell the hibernation core that we've just restored the memory */ + movq %rax, in_suspend(%rip) + ret |