GNU Linux-libre 4.14.266-gnu1
[releases.git] / 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 DEF_NATIVE(pv_irq_ops, irq_disable, "cli");
7 DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
8 DEF_NATIVE(pv_irq_ops, restore_fl, "pushq %rdi; popfq");
9 DEF_NATIVE(pv_irq_ops, save_fl, "pushfq; popq %rax");
10 DEF_NATIVE(pv_mmu_ops, read_cr2, "movq %cr2, %rax");
11 DEF_NATIVE(pv_mmu_ops, read_cr3, "movq %cr3, %rax");
12 DEF_NATIVE(pv_mmu_ops, write_cr3, "movq %rdi, %cr3");
13 DEF_NATIVE(pv_cpu_ops, wbinvd, "wbinvd");
14
15 DEF_NATIVE(pv_cpu_ops, usergs_sysret64, "swapgs; sysretq");
16 DEF_NATIVE(pv_cpu_ops, swapgs, "swapgs");
17
18 DEF_NATIVE(, mov32, "mov %edi, %eax");
19 DEF_NATIVE(, mov64, "mov %rdi, %rax");
20
21 #if defined(CONFIG_PARAVIRT_SPINLOCKS)
22 DEF_NATIVE(pv_lock_ops, queued_spin_unlock, "movb $0, (%rdi)");
23 DEF_NATIVE(pv_lock_ops, vcpu_is_preempted, "xor %rax, %rax");
24 #endif
25
26 unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
27 {
28         return paravirt_patch_insns(insnbuf, len,
29                                     start__mov32, end__mov32);
30 }
31
32 unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
33 {
34         return paravirt_patch_insns(insnbuf, len,
35                                     start__mov64, end__mov64);
36 }
37
38 extern bool pv_is_native_spin_unlock(void);
39 extern bool pv_is_native_vcpu_is_preempted(void);
40
41 unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
42                       unsigned long addr, unsigned len)
43 {
44         const unsigned char *start, *end;
45         unsigned ret;
46
47 #define PATCH_SITE(ops, x)                                      \
48                 case PARAVIRT_PATCH(ops.x):                     \
49                         start = start_##ops##_##x;              \
50                         end = end_##ops##_##x;                  \
51                         goto patch_site
52         switch(type) {
53                 PATCH_SITE(pv_irq_ops, restore_fl);
54                 PATCH_SITE(pv_irq_ops, save_fl);
55                 PATCH_SITE(pv_irq_ops, irq_enable);
56                 PATCH_SITE(pv_irq_ops, irq_disable);
57                 PATCH_SITE(pv_cpu_ops, usergs_sysret64);
58                 PATCH_SITE(pv_cpu_ops, swapgs);
59                 PATCH_SITE(pv_mmu_ops, read_cr2);
60                 PATCH_SITE(pv_mmu_ops, read_cr3);
61                 PATCH_SITE(pv_mmu_ops, write_cr3);
62                 PATCH_SITE(pv_cpu_ops, wbinvd);
63 #if defined(CONFIG_PARAVIRT_SPINLOCKS)
64                 case PARAVIRT_PATCH(pv_lock_ops.queued_spin_unlock):
65                         if (pv_is_native_spin_unlock()) {
66                                 start = start_pv_lock_ops_queued_spin_unlock;
67                                 end   = end_pv_lock_ops_queued_spin_unlock;
68                                 goto patch_site;
69                         }
70                         goto patch_default;
71
72                 case PARAVIRT_PATCH(pv_lock_ops.vcpu_is_preempted):
73                         if (pv_is_native_vcpu_is_preempted()) {
74                                 start = start_pv_lock_ops_vcpu_is_preempted;
75                                 end   = end_pv_lock_ops_vcpu_is_preempted;
76                                 goto patch_site;
77                         }
78                         goto patch_default;
79 #endif
80
81         default:
82 patch_default: __maybe_unused
83                 ret = paravirt_patch_default(type, clobbers, ibuf, addr, len);
84                 break;
85
86 patch_site:
87                 ret = paravirt_patch_insns(ibuf, len, start, end);
88                 break;
89         }
90 #undef PATCH_SITE
91         return ret;
92 }