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/* Copyright 2004,2005 Pavel Machek <pavel@suse.cz>, Andi Kleen <ak@suse.de>, Rafael J. Wysocki <rjw@sisk.pl>
*
* Distribute under GPLv2.
*
* 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
* your own stack under you is bad idea.
*/
.text
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/page.h>
#include <asm/asm-offsets.h>
ENTRY(swsusp_arch_suspend)
movq %rsp, saved_context_esp(%rip)
movq %rax, saved_context_eax(%rip)
movq %rbx, saved_context_ebx(%rip)
movq %rcx, saved_context_ecx(%rip)
movq %rdx, saved_context_edx(%rip)
movq %rbp, saved_context_ebp(%rip)
movq %rsi, saved_context_esi(%rip)
movq %rdi, saved_context_edi(%rip)
movq %r8, saved_context_r08(%rip)
movq %r9, saved_context_r09(%rip)
movq %r10, saved_context_r10(%rip)
movq %r11, saved_context_r11(%rip)
movq %r12, saved_context_r12(%rip)
movq %r13, saved_context_r13(%rip)
movq %r14, saved_context_r14(%rip)
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
ENTRY(restore_image)
/* switch to temporary page tables */
movq $__PAGE_OFFSET, %rdx
movq temp_level4_pgt(%rip), %rax
subq %rdx, %rax
movq %rax, %cr3
/* Flush TLB */
movq mmu_cr4_features(%rip), %rax
movq %rax, %rdx
andq $~(1<<7), %rdx # PGE
movq %rdx, %cr4; # turn off PGE
movq %cr3, %rcx; # flush TLB
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
/* get addresses from the pbe and copy the page */
movq pbe_address(%rdx), %rsi
movq pbe_orig_address(%rdx), %rdi
movq $(PAGE_SIZE >> 3), %rcx
rep
movsq
/* progress to the next pbe */
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
movq %rax, %cr3
/* Flush TLB, including "global" things (vmalloc) */
movq mmu_cr4_features(%rip), %rax
movq %rax, %rdx
andq $~(1<<7), %rdx; # PGE
movq %rdx, %cr4; # turn off PGE
movq %cr3, %rcx; # flush TLB
movq %rcx, %cr3
movq %rax, %cr4; # turn PGE back on
movq saved_context_esp(%rip), %rsp
movq saved_context_ebp(%rip), %rbp
/* 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
movq saved_context_esi(%rip), %rsi
movq saved_context_edi(%rip), %rdi
movq saved_context_r08(%rip), %r8
movq saved_context_r09(%rip), %r9
movq saved_context_r10(%rip), %r10
movq saved_context_r11(%rip), %r11
movq saved_context_r12(%rip), %r12
movq saved_context_r13(%rip), %r13
movq saved_context_r14(%rip), %r14
movq saved_context_r15(%rip), %r15
pushq saved_context_eflags(%rip) ; popfq
xorq %rax, %rax
/* tell the hibernation core that we've just restored the memory */
movq %rax, in_suspend(%rip)
ret
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