arch/x86/kernel/paravirt_patch_32.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <asm/paravirt.h>
   3
   4 #ifdef CONFIG_PARAVIRT_XXL
   5 DEF_NATIVE(irq, irq_disable, "cli");
   6 DEF_NATIVE(irq, irq_enable, "sti");
   7 DEF_NATIVE(irq, restore_fl, "push %eax; popf");
   8 DEF_NATIVE(irq, save_fl, "pushf; pop %eax");
   9 DEF_NATIVE(cpu, iret, "iret");
  10 DEF_NATIVE(mmu, read_cr2, "mov %cr2, %eax");
  11 DEF_NATIVE(mmu, write_cr3, "mov %eax, %cr3");
  12 DEF_NATIVE(mmu, read_cr3, "mov %cr3, %eax");
  13
  14 unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
  15 {
  16         /* arg in %edx:%eax, return in %edx:%eax */
  17         return 0;
  18 }
  19 #endif
  20
  21 #if defined(CONFIG_PARAVIRT_SPINLOCKS)
  22 DEF_NATIVE(lock, queued_spin_unlock, "movb $0, (%eax)");
  23 DEF_NATIVE(lock, vcpu_is_preempted, "xor %eax, %eax");
  24 #endif
  25
  26 extern bool pv_is_native_spin_unlock(void);
  27 extern bool pv_is_native_vcpu_is_preempted(void);
  28
  29 unsigned native_patch(u8 type, void *ibuf, unsigned long addr, unsigned len)
  30 {
  31 #define PATCH_SITE(ops, x)                                      \
  32         case PARAVIRT_PATCH(ops.x):                             \
  33                 return paravirt_patch_insns(ibuf, len, start_##ops##_##x, end_##ops##_##x)
  34
  35         switch (type) {
  36 #ifdef CONFIG_PARAVIRT_XXL
  37                 PATCH_SITE(irq, irq_disable);
  38                 PATCH_SITE(irq, irq_enable);
  39                 PATCH_SITE(irq, restore_fl);
  40                 PATCH_SITE(irq, save_fl);
  41                 PATCH_SITE(cpu, iret);
  42                 PATCH_SITE(mmu, read_cr2);
  43                 PATCH_SITE(mmu, read_cr3);
  44                 PATCH_SITE(mmu, write_cr3);
  45 #endif
  46 #if defined(CONFIG_PARAVIRT_SPINLOCKS)
  47         case PARAVIRT_PATCH(lock.queued_spin_unlock):
  48                 if (pv_is_native_spin_unlock())
  49                         return paravirt_patch_insns(ibuf, len,
  50                                                     start_lock_queued_spin_unlock,
  51                                                     end_lock_queued_spin_unlock);
  52                 break;
  53
  54         case PARAVIRT_PATCH(lock.vcpu_is_preempted):
  55                 if (pv_is_native_vcpu_is_preempted())
  56                         return paravirt_patch_insns(ibuf, len,
  57                                                     start_lock_vcpu_is_preempted,
  58                                                     end_lock_vcpu_is_preempted);
  59                 break;
  60 #endif
  61
  62         default:
  63                 break;
  64         }
  65 #undef PATCH_SITE
  66         return paravirt_patch_default(type, ibuf, addr, len);
  67 }