arch/x86/kernel/paravirt_patch_64.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <asm/paravirt.h>
   3 #include <asm/asm-offsets.h>
   4 #include <linux/stringify.h>
   5
   6 #ifdef CONFIG_PARAVIRT_XXL
   7 DEF_NATIVE(irq, irq_disable, "cli");
   8 DEF_NATIVE(irq, irq_enable, "sti");
   9 DEF_NATIVE(irq, restore_fl, "pushq %rdi; popfq");
  10 DEF_NATIVE(irq, save_fl, "pushfq; popq %rax");
  11 DEF_NATIVE(mmu, read_cr2, "movq %cr2, %rax");
  12 DEF_NATIVE(mmu, read_cr3, "movq %cr3, %rax");
  13 DEF_NATIVE(mmu, write_cr3, "movq %rdi, %cr3");
  14 DEF_NATIVE(cpu, wbinvd, "wbinvd");
  15
  16 DEF_NATIVE(cpu, usergs_sysret64, "swapgs; sysretq");
  17 DEF_NATIVE(cpu, swapgs, "swapgs");
  18 #endif
  19
  20 DEF_NATIVE(, mov32, "mov %edi, %eax");
  21 DEF_NATIVE(, mov64, "mov %rdi, %rax");
  22
  23 #if defined(CONFIG_PARAVIRT_SPINLOCKS)
  24 DEF_NATIVE(lock, queued_spin_unlock, "movb $0, (%rdi)");
  25 DEF_NATIVE(lock, vcpu_is_preempted, "xor %eax, %eax");
  26 #endif
  27
  28 unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
  29 {
  30         return paravirt_patch_insns(insnbuf, len,
  31                                     start__mov32, end__mov32);
  32 }
  33
  34 unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
  35 {
  36         return paravirt_patch_insns(insnbuf, len,
  37                                     start__mov64, end__mov64);
  38 }
  39
  40 extern bool pv_is_native_spin_unlock(void);
  41 extern bool pv_is_native_vcpu_is_preempted(void);
  42
  43 unsigned native_patch(u8 type, void *ibuf, unsigned long addr, unsigned len)
  44 {
  45 #define PATCH_SITE(ops, x)                                      \
  46         case PARAVIRT_PATCH(ops.x):                             \
  47                 return paravirt_patch_insns(ibuf, len, start_##ops##_##x, end_##ops##_##x)
  48
  49         switch (type) {
  50 #ifdef CONFIG_PARAVIRT_XXL
  51                 PATCH_SITE(irq, restore_fl);
  52                 PATCH_SITE(irq, save_fl);
  53                 PATCH_SITE(irq, irq_enable);
  54                 PATCH_SITE(irq, irq_disable);
  55                 PATCH_SITE(cpu, usergs_sysret64);
  56                 PATCH_SITE(cpu, swapgs);
  57                 PATCH_SITE(cpu, wbinvd);
  58                 PATCH_SITE(mmu, read_cr2);
  59                 PATCH_SITE(mmu, read_cr3);
  60                 PATCH_SITE(mmu, write_cr3);
  61 #endif
  62 #if defined(CONFIG_PARAVIRT_SPINLOCKS)
  63         case PARAVIRT_PATCH(lock.queued_spin_unlock):
  64                 if (pv_is_native_spin_unlock())
  65                         return paravirt_patch_insns(ibuf, len,
  66                                                     start_lock_queued_spin_unlock,
  67                                                     end_lock_queued_spin_unlock);
  68                 break;
  69
  70         case PARAVIRT_PATCH(lock.vcpu_is_preempted):
  71                 if (pv_is_native_vcpu_is_preempted())
  72                         return paravirt_patch_insns(ibuf, len,
  73                                                     start_lock_vcpu_is_preempted,
  74                                                     end_lock_vcpu_is_preempted);
  75                 break;
  76 #endif
  77
  78         default:
  79                 break;
  80         }
  81 #undef PATCH_SITE
  82         return paravirt_patch_default(type, ibuf, addr, len);
  83 }