arch/x86/kernel/suspend_asm_64.S

   1 /* Copyright 2004,2005 Pavel Machek <pavel@suse.cz>, Andi Kleen <ak@suse.de>, Rafael J. Wysocki <rjw@sisk.pl>
   2  *
   3  * Distribute under GPLv2.
   4  *
   5  * swsusp_arch_resume must not use any stack or any nonlocal variables while
   6  * copying pages:
   7  *
   8  * Its rewriting one kernel image with another. What is stack in "old"
   9  * image could very well be data page in "new" image, and overwriting
  10  * your own stack under you is bad idea.
  11  */
  12
  13         .text
  14 #include <linux/linkage.h>
  15 #include <asm/segment.h>
  16 #include <asm/page.h>
  17 #include <asm/asm-offsets.h>
  18
  19 ENTRY(swsusp_arch_suspend)
  20         movq    $saved_context, %rax
  21         movq    %rsp, pt_regs_sp(%rax)
  22         movq    %rbp, pt_regs_bp(%rax)
  23         movq    %rsi, pt_regs_si(%rax)
  24         movq    %rdi, pt_regs_di(%rax)
  25         movq    %rbx, pt_regs_bx(%rax)
  26         movq    %rcx, pt_regs_cx(%rax)
  27         movq    %rdx, pt_regs_dx(%rax)
  28         movq    %r8, pt_regs_r8(%rax)
  29         movq    %r9, pt_regs_r9(%rax)
  30         movq    %r10, pt_regs_r10(%rax)
  31         movq    %r11, pt_regs_r11(%rax)
  32         movq    %r12, pt_regs_r12(%rax)
  33         movq    %r13, pt_regs_r13(%rax)
  34         movq    %r14, pt_regs_r14(%rax)
  35         movq    %r15, pt_regs_r15(%rax)
  36         pushfq
  37         popq    pt_regs_flags(%rax)
  38
  39         /* save the address of restore_registers */
  40         movq    $restore_registers, %rax
  41         movq    %rax, restore_jump_address(%rip)
  42         /* save cr3 */
  43         movq    %cr3, %rax
  44         movq    %rax, restore_cr3(%rip)
  45
  46         call swsusp_save
  47         ret
  48
  49 ENTRY(restore_image)
  50         /* switch to temporary page tables */
  51         movq    $__PAGE_OFFSET, %rdx
  52         movq    temp_level4_pgt(%rip), %rax
  53         subq    %rdx, %rax
  54         movq    %rax, %cr3
  55         /* Flush TLB */
  56         movq    mmu_cr4_features(%rip), %rax
  57         movq    %rax, %rdx
  58         andq    $~(1<<7), %rdx  # PGE
  59         movq    %rdx, %cr4;  # turn off PGE
  60         movq    %cr3, %rcx;  # flush TLB
  61         movq    %rcx, %cr3;
  62         movq    %rax, %cr4;  # turn PGE back on
  63
  64         /* prepare to jump to the image kernel */
  65         movq    restore_jump_address(%rip), %rax
  66         movq    restore_cr3(%rip), %rbx
  67
  68         /* prepare to copy image data to their original locations */
  69         movq    restore_pblist(%rip), %rdx
  70         movq    relocated_restore_code(%rip), %rcx
  71         jmpq    *%rcx
  72
  73         /* code below has been relocated to a safe page */
  74 ENTRY(core_restore_code)
  75 loop:
  76         testq   %rdx, %rdx
  77         jz      done
  78
  79         /* get addresses from the pbe and copy the page */
  80         movq    pbe_address(%rdx), %rsi
  81         movq    pbe_orig_address(%rdx), %rdi
  82         movq    $(PAGE_SIZE >> 3), %rcx
  83         rep
  84         movsq
  85
  86         /* progress to the next pbe */
  87         movq    pbe_next(%rdx), %rdx
  88         jmp     loop
  89 done:
  90         /* jump to the restore_registers address from the image header */
  91         jmpq    *%rax
  92         /*
  93          * NOTE: This assumes that the boot kernel's text mapping covers the
  94          * image kernel's page containing restore_registers and the address of
  95          * this page is the same as in the image kernel's text mapping (it
  96          * should always be true, because the text mapping is linear, starting
  97          * from 0, and is supposed to cover the entire kernel text for every
  98          * kernel).
  99          *
 100          * code below belongs to the image kernel
 101          */
 102
 103 ENTRY(restore_registers)
 104         /* go back to the original page tables */
 105         movq    %rbx, %cr3
 106
 107         /* Flush TLB, including "global" things (vmalloc) */
 108         movq    mmu_cr4_features(%rip), %rax
 109         movq    %rax, %rdx
 110         andq    $~(1<<7), %rdx;  # PGE
 111         movq    %rdx, %cr4;  # turn off PGE
 112         movq    %cr3, %rcx;  # flush TLB
 113         movq    %rcx, %cr3
 114         movq    %rax, %cr4;  # turn PGE back on
 115
 116         /* We don't restore %rax, it must be 0 anyway */
 117         movq    $saved_context, %rax
 118         movq    pt_regs_sp(%rax), %rsp
 119         movq    pt_regs_bp(%rax), %rbp
 120         movq    pt_regs_si(%rax), %rsi
 121         movq    pt_regs_di(%rax), %rdi
 122         movq    pt_regs_bx(%rax), %rbx
 123         movq    pt_regs_cx(%rax), %rcx
 124         movq    pt_regs_dx(%rax), %rdx
 125         movq    pt_regs_r8(%rax), %r8
 126         movq    pt_regs_r9(%rax), %r9
 127         movq    pt_regs_r10(%rax), %r10
 128         movq    pt_regs_r11(%rax), %r11
 129         movq    pt_regs_r12(%rax), %r12
 130         movq    pt_regs_r13(%rax), %r13
 131         movq    pt_regs_r14(%rax), %r14
 132         movq    pt_regs_r15(%rax), %r15
 133         pushq   pt_regs_flags(%rax)
 134         popfq
 135
 136         xorq    %rax, %rax
 137
 138         /* tell the hibernation core that we've just restored the memory */
 139         movq    %rax, in_suspend(%rip)
 140
 141         ret