LXR linux/arch/x86/kernel/trampoline.c

   1#include <linux/io.h>
   2
   3#include <asm/trampoline.h>
   4#include <asm/e820.h>
   5
   6#if defined(CONFIG_X86_64) && defined(CONFIG_ACPI_SLEEP)
   7#define __trampinit
   8#define __trampinitdata
   9#else
  10#define __trampinit __cpuinit
  11#define __trampinitdata __cpuinitdata
  12#endif
  13
  14/* ready for x86_64 and x86 */
  15unsigned char *__trampinitdata trampoline_base = __va(TRAMPOLINE_BASE);
  16
  17void __init reserve_trampoline_memory(void)
  18{
  19#ifdef CONFIG_X86_32
  20        /*
  21         * But first pinch a few for the stack/trampoline stuff
  22         * FIXME: Don't need the extra page at 4K, but need to fix
  23         * trampoline before removing it. (see the GDT stuff)
  24         */
  25        reserve_early(PAGE_SIZE, PAGE_SIZE + PAGE_SIZE, "EX TRAMPOLINE");
  26#endif
  27        /* Has to be in very low memory so we can execute real-mode AP code. */
  28        reserve_early(TRAMPOLINE_BASE, TRAMPOLINE_BASE + TRAMPOLINE_SIZE,
  29                        "TRAMPOLINE");
  30}
  31
  32/*
  33 * Currently trivial. Write the real->protected mode
  34 * bootstrap into the page concerned. The caller
  35 * has made sure it's suitably aligned.
  36 */
  37unsigned long __trampinit setup_trampoline(void)
  38{
  39        memcpy(trampoline_base, trampoline_data, TRAMPOLINE_SIZE);
  40        return virt_to_phys(trampoline_base);
  41}
  42