acrn-kernel/arch/x86_64/kernel/suspend.c

223 lines
5.8 KiB
C

/*
* Suspend support specific for i386.
*
* Distribute under GPLv2
*
* Copyright (c) 2002 Pavel Machek <pavel@suse.cz>
* Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
*/
#include <linux/smp.h>
#include <linux/suspend.h>
#include <asm/proto.h>
#include <asm/page.h>
#include <asm/pgtable.h>
struct saved_context saved_context;
unsigned long saved_context_eax, saved_context_ebx, saved_context_ecx, saved_context_edx;
unsigned long saved_context_esp, saved_context_ebp, saved_context_esi, saved_context_edi;
unsigned long saved_context_r08, saved_context_r09, saved_context_r10, saved_context_r11;
unsigned long saved_context_r12, saved_context_r13, saved_context_r14, saved_context_r15;
unsigned long saved_context_eflags;
void __save_processor_state(struct saved_context *ctxt)
{
kernel_fpu_begin();
/*
* descriptor tables
*/
asm volatile ("sgdt %0" : "=m" (ctxt->gdt_limit));
asm volatile ("sidt %0" : "=m" (ctxt->idt_limit));
asm volatile ("str %0" : "=m" (ctxt->tr));
/* XMM0..XMM15 should be handled by kernel_fpu_begin(). */
/* EFER should be constant for kernel version, no need to handle it. */
/*
* segment registers
*/
asm volatile ("movw %%ds, %0" : "=m" (ctxt->ds));
asm volatile ("movw %%es, %0" : "=m" (ctxt->es));
asm volatile ("movw %%fs, %0" : "=m" (ctxt->fs));
asm volatile ("movw %%gs, %0" : "=m" (ctxt->gs));
asm volatile ("movw %%ss, %0" : "=m" (ctxt->ss));
rdmsrl(MSR_FS_BASE, ctxt->fs_base);
rdmsrl(MSR_GS_BASE, ctxt->gs_base);
rdmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
/*
* control registers
*/
asm volatile ("movq %%cr0, %0" : "=r" (ctxt->cr0));
asm volatile ("movq %%cr2, %0" : "=r" (ctxt->cr2));
asm volatile ("movq %%cr3, %0" : "=r" (ctxt->cr3));
asm volatile ("movq %%cr4, %0" : "=r" (ctxt->cr4));
asm volatile ("movq %%cr8, %0" : "=r" (ctxt->cr8));
}
void save_processor_state(void)
{
__save_processor_state(&saved_context);
}
static void do_fpu_end(void)
{
/*
* Restore FPU regs if necessary
*/
kernel_fpu_end();
}
void __restore_processor_state(struct saved_context *ctxt)
{
/*
* control registers
*/
asm volatile ("movq %0, %%cr8" :: "r" (ctxt->cr8));
asm volatile ("movq %0, %%cr4" :: "r" (ctxt->cr4));
asm volatile ("movq %0, %%cr3" :: "r" (ctxt->cr3));
asm volatile ("movq %0, %%cr2" :: "r" (ctxt->cr2));
asm volatile ("movq %0, %%cr0" :: "r" (ctxt->cr0));
/*
* now restore the descriptor tables to their proper values
* ltr is done i fix_processor_context().
*/
asm volatile ("lgdt %0" :: "m" (ctxt->gdt_limit));
asm volatile ("lidt %0" :: "m" (ctxt->idt_limit));
/*
* segment registers
*/
asm volatile ("movw %0, %%ds" :: "r" (ctxt->ds));
asm volatile ("movw %0, %%es" :: "r" (ctxt->es));
asm volatile ("movw %0, %%fs" :: "r" (ctxt->fs));
load_gs_index(ctxt->gs);
asm volatile ("movw %0, %%ss" :: "r" (ctxt->ss));
wrmsrl(MSR_FS_BASE, ctxt->fs_base);
wrmsrl(MSR_GS_BASE, ctxt->gs_base);
wrmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
fix_processor_context();
do_fpu_end();
mtrr_ap_init();
}
void restore_processor_state(void)
{
__restore_processor_state(&saved_context);
}
void fix_processor_context(void)
{
int cpu = smp_processor_id();
struct tss_struct *t = &per_cpu(init_tss, cpu);
set_tss_desc(cpu,t); /* This just modifies memory; should not be neccessary. But... This is neccessary, because 386 hardware has concept of busy TSS or some similar stupidity. */
cpu_gdt(cpu)[GDT_ENTRY_TSS].type = 9;
syscall_init(); /* This sets MSR_*STAR and related */
load_TR_desc(); /* This does ltr */
load_LDT(&current->active_mm->context); /* This does lldt */
/*
* Now maybe reload the debug registers
*/
if (current->thread.debugreg7){
loaddebug(&current->thread, 0);
loaddebug(&current->thread, 1);
loaddebug(&current->thread, 2);
loaddebug(&current->thread, 3);
/* no 4 and 5 */
loaddebug(&current->thread, 6);
loaddebug(&current->thread, 7);
}
}
#ifdef CONFIG_SOFTWARE_SUSPEND
/* Defined in arch/x86_64/kernel/suspend_asm.S */
extern int restore_image(void);
pgd_t *temp_level4_pgt;
static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end)
{
long i, j;
i = pud_index(address);
pud = pud + i;
for (; i < PTRS_PER_PUD; pud++, i++) {
unsigned long paddr;
pmd_t *pmd;
paddr = address + i*PUD_SIZE;
if (paddr >= end)
break;
pmd = (pmd_t *)get_safe_page(GFP_ATOMIC);
if (!pmd)
return -ENOMEM;
set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
for (j = 0; j < PTRS_PER_PMD; pmd++, j++, paddr += PMD_SIZE) {
unsigned long pe;
if (paddr >= end)
break;
pe = _PAGE_NX | _PAGE_PSE | _KERNPG_TABLE | paddr;
pe &= __supported_pte_mask;
set_pmd(pmd, __pmd(pe));
}
}
return 0;
}
static int set_up_temporary_mappings(void)
{
unsigned long start, end, next;
int error;
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 */
start = (unsigned long)pfn_to_kaddr(0);
end = (unsigned long)pfn_to_kaddr(end_pfn);
for (; start < end; start = next) {
pud_t *pud = (pud_t *)get_safe_page(GFP_ATOMIC);
if (!pud)
return -ENOMEM;
next = start + PGDIR_SIZE;
if (next > end)
next = end;
if ((error = res_phys_pud_init(pud, __pa(start), __pa(next))))
return error;
set_pgd(temp_level4_pgt + pgd_index(start),
mk_kernel_pgd(__pa(pud)));
}
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;
restore_image();
return 0;
}
#endif /* CONFIG_SOFTWARE_SUSPEND */