linux/arch/x86/include/asm/suspend_64.h

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/*
* Copyright 2001-2003 Pavel Machek <pavel@suse.cz>
* Based on code
* Copyright 2001 Patrick Mochel <mochel@osdl.org>
*/
#ifndef _ASM_X86_SUSPEND_64_H
#define _ASM_X86_SUSPEND_64_H
#include <asm/desc.h>
#include <asm/i387.h>
/*
* Image of the saved processor state, used by the low level ACPI suspend to
* RAM code and by the low level hibernation code.
*
* If you modify it, fix arch/x86/kernel/acpi/wakeup_64.S and make sure that
* __save/__restore_processor_state(), defined in arch/x86/kernel/suspend_64.c,
* still work as required.
*/
struct saved_context {
struct pt_regs regs;
u16 ds, es, fs, gs, ss;
unsigned long gs_base, gs_kernel_base, fs_base;
unsigned long cr0, cr2, cr3, cr4, cr8;
u64 misc_enable;
bool misc_enable_saved;
unsigned long efer;
x86, gdt, hibernate: Store/load GDT for hibernate path. The git commite7a5cd063c7b4c58417f674821d63f5eb6747e37 ("x86-64, gdt: Store/load GDT for ACPI S3 or hibernate/resume path is not needed.") assumes that for the hibernate path the booting kernel and the resuming kernel MUST be the same. That is certainly the case for a 32-bit kernel (see check_image_kernel and CONFIG_ARCH_HIBERNATION_HEADER config option). However for 64-bit kernels it is OK to have a different kernel version (and size of the image) of the booting and resuming kernels. Hence the above mentioned git commit introduces an regression. This patch fixes it by introducing a 'struct desc_ptr gdt_desc' back in the 'struct saved_context'. However instead of having in the 'save_processor_state' and 'restore_processor_state' the store/load_gdt calls, we are only saving the GDT in the save_processor_state. For the restore path the lgdt operation is done in hibernate_asm_[32|64].S in the 'restore_registers' path. The apt reader of this description will recognize that only 64-bit kernels need this treatment, not 32-bit. This patch adds the logic in the 32-bit path to be more similar to 64-bit so that in the future the unification process can take advantage of this. [ hpa: this also reverts an inadvertent on-disk format change ] Suggested-by: "H. Peter Anvin" <hpa@zytor.com> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Link: http://lkml.kernel.org/r/1367459610-9656-2-git-send-email-konrad.wilk@oracle.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-05-02 01:53:30 +00:00
u16 gdt_pad; /* Unused */
struct desc_ptr gdt_desc;
u16 idt_pad;
u16 idt_limit;
unsigned long idt_base;
u16 ldt;
u16 tss;
unsigned long tr;
unsigned long safety;
unsigned long return_address;
} __attribute__((packed));
#define loaddebug(thread,register) \
set_debugreg((thread)->debugreg##register, register)
/* routines for saving/restoring kernel state */
extern int acpi_save_state_mem(void);
Hibernation: Arbitrary boot kernel support on x86_64 Make it possible to restore a hibernation image on x86_64 with the help of a kernel different from the one in the image. The idea is to split the core restoration code into two separate parts and to place each of them in a different page.  The first part belongs to the boot kernel and is executed as the last step of the image kernel's memory restoration procedure.  Before being executed, it is relocated to a safe page that won't be overwritten while copying the image kernel pages. The final operation performed by it is a jump to the second part of the core restoration code that belongs to the image kernel and has just been restored. This code makes the CPU switch to the image kernel's page tables and restores the state of general purpose registers (including the stack pointer) from before the hibernation. The main issue with this idea is that in order to jump to the second part of the core restoration code the boot kernel needs to know its address.  However, this address may be passed to it in the image header.  Namely, the part of the image header previously used for checking if the version of the image kernel is correct can be replaced with some architecture specific data that will allow the boot kernel to jump to the right address within the image kernel.  These data should also be used for checking if the image kernel is compatible with the boot kernel (as far as the memory restroration procedure is concerned). It can be done, for example, with the help of a "magic" value that has to be equal in both kernels, so that they can be regarded as compatible. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 10:04:53 +00:00
extern char core_restore_code;
extern char restore_registers;
#endif /* _ASM_X86_SUSPEND_64_H */