include/asm-i386/paravirt.h

   1 #ifndef __ASM_PARAVIRT_H
   2 #define __ASM_PARAVIRT_H
   3 /* Various instructions on x86 need to be replaced for
   4  * para-virtualization: those hooks are defined here. */
   5 #include <linux/linkage.h>
   6 #include <linux/stringify.h>
   7 #include <asm/page.h>
   8
   9 #ifdef CONFIG_PARAVIRT
  10 /* These are the most performance critical ops, so we want to be able to patch
  11  * callers */
  12 #define PARAVIRT_IRQ_DISABLE 0
  13 #define PARAVIRT_IRQ_ENABLE 1
  14 #define PARAVIRT_RESTORE_FLAGS 2
  15 #define PARAVIRT_SAVE_FLAGS 3
  16 #define PARAVIRT_SAVE_FLAGS_IRQ_DISABLE 4
  17 #define PARAVIRT_INTERRUPT_RETURN 5
  18 #define PARAVIRT_STI_SYSEXIT 6
  19
  20 /* Bitmask of what can be clobbered: usually at least eax. */
  21 #define CLBR_NONE 0x0
  22 #define CLBR_EAX 0x1
  23 #define CLBR_ECX 0x2
  24 #define CLBR_EDX 0x4
  25 #define CLBR_ANY 0x7
  26
  27 #ifndef __ASSEMBLY__
  28 struct thread_struct;
  29 struct Xgt_desc_struct;
  30 struct tss_struct;
  31 struct mm_struct;
  32 struct paravirt_ops
  33 {
  34         unsigned int kernel_rpl;
  35         int paravirt_enabled;
  36         const char *name;
  37
  38         /*
  39          * Patch may replace one of the defined code sequences with arbitrary
  40          * code, subject to the same register constraints.  This generally
  41          * means the code is not free to clobber any registers other than EAX.
  42          * The patch function should return the number of bytes of code
  43          * generated, as we nop pad the rest in generic code.
  44          */
  45         unsigned (*patch)(u8 type, u16 clobber, void *firstinsn, unsigned len);
  46
  47         void (*arch_setup)(void);
  48         char *(*memory_setup)(void);
  49         void (*init_IRQ)(void);
  50
  51         void (*banner)(void);
  52
  53         unsigned long (*get_wallclock)(void);
  54         int (*set_wallclock)(unsigned long);
  55         void (*time_init)(void);
  56
  57         /* All the function pointers here are declared as "fastcall"
  58            so that we get a specific register-based calling
  59            convention.  This makes it easier to implement inline
  60            assembler replacements. */
  61
  62         void (*cpuid)(unsigned int *eax, unsigned int *ebx,
  63                       unsigned int *ecx, unsigned int *edx);
  64
  65         unsigned long (*get_debugreg)(int regno);
  66         void (*set_debugreg)(int regno, unsigned long value);
  67
  68         void (*clts)(void);
  69
  70         unsigned long (*read_cr0)(void);
  71         void (*write_cr0)(unsigned long);
  72
  73         unsigned long (*read_cr2)(void);
  74         void (*write_cr2)(unsigned long);
  75
  76         unsigned long (*read_cr3)(void);
  77         void (*write_cr3)(unsigned long);
  78
  79         unsigned long (*read_cr4_safe)(void);
  80         unsigned long (*read_cr4)(void);
  81         void (*write_cr4)(unsigned long);
  82
  83         unsigned long (*save_fl)(void);
  84         void (*restore_fl)(unsigned long);
  85         void (*irq_disable)(void);
  86         void (*irq_enable)(void);
  87         void (*safe_halt)(void);
  88         void (*halt)(void);
  89         void (*wbinvd)(void);
  90
  91         /* err = 0/-EFAULT.  wrmsr returns 0/-EFAULT. */
  92         u64 (*read_msr)(unsigned int msr, int *err);
  93         int (*write_msr)(unsigned int msr, u64 val);
  94
  95         u64 (*read_tsc)(void);
  96         u64 (*read_pmc)(void);
  97         u64 (*get_scheduled_cycles)(void);
  98
  99         void (*load_tr_desc)(void);
 100         void (*load_gdt)(const struct Xgt_desc_struct *);
 101         void (*load_idt)(const struct Xgt_desc_struct *);
 102         void (*store_gdt)(struct Xgt_desc_struct *);
 103         void (*store_idt)(struct Xgt_desc_struct *);
 104         void (*set_ldt)(const void *desc, unsigned entries);
 105         unsigned long (*store_tr)(void);
 106         void (*load_tls)(struct thread_struct *t, unsigned int cpu);
 107         void (*write_ldt_entry)(void *dt, int entrynum,
 108                                          u32 low, u32 high);
 109         void (*write_gdt_entry)(void *dt, int entrynum,
 110                                          u32 low, u32 high);
 111         void (*write_idt_entry)(void *dt, int entrynum,
 112                                          u32 low, u32 high);
 113         void (*load_esp0)(struct tss_struct *tss,
 114                                    struct thread_struct *thread);
 115
 116         void (*set_iopl_mask)(unsigned mask);
 117
 118         void (*io_delay)(void);
 119         void (*const_udelay)(unsigned long loops);
 120
 121 #ifdef CONFIG_X86_LOCAL_APIC
 122         void (*apic_write)(unsigned long reg, unsigned long v);
 123         void (*apic_write_atomic)(unsigned long reg, unsigned long v);
 124         unsigned long (*apic_read)(unsigned long reg);
 125         void (*setup_boot_clock)(void);
 126         void (*setup_secondary_clock)(void);
 127 #endif
 128
 129         void (*flush_tlb_user)(void);
 130         void (*flush_tlb_kernel)(void);
 131         void (*flush_tlb_single)(u32 addr);
 132
 133         void (*alloc_pt)(u32 pfn);
 134         void (*alloc_pd)(u32 pfn);
 135         void (*alloc_pd_clone)(u32 pfn, u32 clonepfn, u32 start, u32 count);
 136         void (*release_pt)(u32 pfn);
 137         void (*release_pd)(u32 pfn);
 138
 139         void (*set_pte)(pte_t *ptep, pte_t pteval);
 140         void (*set_pte_at)(struct mm_struct *mm, u32 addr, pte_t *ptep, pte_t pteval);
 141         void (*set_pmd)(pmd_t *pmdp, pmd_t pmdval);
 142         void (*pte_update)(struct mm_struct *mm, u32 addr, pte_t *ptep);
 143         void (*pte_update_defer)(struct mm_struct *mm, u32 addr, pte_t *ptep);
 144 #ifdef CONFIG_X86_PAE
 145         void (*set_pte_atomic)(pte_t *ptep, pte_t pteval);
 146         void (*set_pte_present)(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte);
 147         void (*set_pud)(pud_t *pudp, pud_t pudval);
 148         void (*pte_clear)(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
 149         void (*pmd_clear)(pmd_t *pmdp);
 150 #endif
 151
 152         void (*set_lazy_mode)(int mode);
 153
 154         /* These two are jmp to, not actually called. */
 155         void (*irq_enable_sysexit)(void);
 156         void (*iret)(void);
 157
 158         void (*startup_ipi_hook)(int phys_apicid, unsigned long start_eip, unsigned long start_esp);
 159 };
 160
 161 /* Mark a paravirt probe function. */
 162 #define paravirt_probe(fn)                                              \
 163  static asmlinkage void (*__paravirtprobe_##fn)(void) __attribute_used__ \
 164                 __attribute__((__section__(".paravirtprobe"))) = fn
 165
 166 extern struct paravirt_ops paravirt_ops;
 167
 168 #define paravirt_enabled() (paravirt_ops.paravirt_enabled)
 169
 170 static inline void load_esp0(struct tss_struct *tss,
 171                              struct thread_struct *thread)
 172 {
 173         paravirt_ops.load_esp0(tss, thread);
 174 }
 175
 176 #define ARCH_SETUP                      paravirt_ops.arch_setup();
 177 static inline unsigned long get_wallclock(void)
 178 {
 179         return paravirt_ops.get_wallclock();
 180 }
 181
 182 static inline int set_wallclock(unsigned long nowtime)
 183 {
 184         return paravirt_ops.set_wallclock(nowtime);
 185 }
 186
 187 static inline void do_time_init(void)
 188 {
 189         return paravirt_ops.time_init();
 190 }
 191
 192 /* The paravirtualized CPUID instruction. */
 193 static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
 194                            unsigned int *ecx, unsigned int *edx)
 195 {
 196         paravirt_ops.cpuid(eax, ebx, ecx, edx);
 197 }
 198
 199 /*
 200  * These special macros can be used to get or set a debugging register
 201  */
 202 #define get_debugreg(var, reg) var = paravirt_ops.get_debugreg(reg)
 203 #define set_debugreg(val, reg) paravirt_ops.set_debugreg(reg, val)
 204
 205 #define clts() paravirt_ops.clts()
 206
 207 #define read_cr0() paravirt_ops.read_cr0()
 208 #define write_cr0(x) paravirt_ops.write_cr0(x)
 209
 210 #define read_cr2() paravirt_ops.read_cr2()
 211 #define write_cr2(x) paravirt_ops.write_cr2(x)
 212
 213 #define read_cr3() paravirt_ops.read_cr3()
 214 #define write_cr3(x) paravirt_ops.write_cr3(x)
 215
 216 #define read_cr4() paravirt_ops.read_cr4()
 217 #define read_cr4_safe(x) paravirt_ops.read_cr4_safe()
 218 #define write_cr4(x) paravirt_ops.write_cr4(x)
 219
 220 static inline void raw_safe_halt(void)
 221 {
 222         paravirt_ops.safe_halt();
 223 }
 224
 225 static inline void halt(void)
 226 {
 227         paravirt_ops.safe_halt();
 228 }
 229 #define wbinvd() paravirt_ops.wbinvd()
 230
 231 #define get_kernel_rpl()  (paravirt_ops.kernel_rpl)
 232
 233 #define rdmsr(msr,val1,val2) do {                               \
 234         int _err;                                               \
 235         u64 _l = paravirt_ops.read_msr(msr,&_err);              \
 236         val1 = (u32)_l;                                         \
 237         val2 = _l >> 32;                                        \
 238 } while(0)
 239
 240 #define wrmsr(msr,val1,val2) do {                               \
 241         u64 _l = ((u64)(val2) << 32) | (val1);                  \
 242         paravirt_ops.write_msr((msr), _l);                      \
 243 } while(0)
 244
 245 #define rdmsrl(msr,val) do {                                    \
 246         int _err;                                               \
 247         val = paravirt_ops.read_msr((msr),&_err);               \
 248 } while(0)
 249
 250 #define wrmsrl(msr,val) (paravirt_ops.write_msr((msr),(val)))
 251 #define wrmsr_safe(msr,a,b) ({                                  \
 252         u64 _l = ((u64)(b) << 32) | (a);                        \
 253         paravirt_ops.write_msr((msr),_l);                       \
 254 })
 255
 256 /* rdmsr with exception handling */
 257 #define rdmsr_safe(msr,a,b) ({                                  \
 258         int _err;                                               \
 259         u64 _l = paravirt_ops.read_msr(msr,&_err);              \
 260         (*a) = (u32)_l;                                         \
 261         (*b) = _l >> 32;                                        \
 262         _err; })
 263
 264 #define rdtsc(low,high) do {                                    \
 265         u64 _l = paravirt_ops.read_tsc();                       \
 266         low = (u32)_l;                                          \
 267         high = _l >> 32;                                        \
 268 } while(0)
 269
 270 #define rdtscl(low) do {                                        \
 271         u64 _l = paravirt_ops.read_tsc();                       \
 272         low = (int)_l;                                          \
 273 } while(0)
 274
 275 #define rdtscll(val) (val = paravirt_ops.read_tsc())
 276
 277 #define get_scheduled_cycles(val) (val = paravirt_ops.get_scheduled_cycles())
 278
 279 #define write_tsc(val1,val2) wrmsr(0x10, val1, val2)
 280
 281 #define rdpmc(counter,low,high) do {                            \
 282         u64 _l = paravirt_ops.read_pmc();                       \
 283         low = (u32)_l;                                          \
 284         high = _l >> 32;                                        \
 285 } while(0)
 286
 287 #define load_TR_desc() (paravirt_ops.load_tr_desc())
 288 #define load_gdt(dtr) (paravirt_ops.load_gdt(dtr))
 289 #define load_idt(dtr) (paravirt_ops.load_idt(dtr))
 290 #define set_ldt(addr, entries) (paravirt_ops.set_ldt((addr), (entries)))
 291 #define store_gdt(dtr) (paravirt_ops.store_gdt(dtr))
 292 #define store_idt(dtr) (paravirt_ops.store_idt(dtr))
 293 #define store_tr(tr) ((tr) = paravirt_ops.store_tr())
 294 #define load_TLS(t,cpu) (paravirt_ops.load_tls((t),(cpu)))
 295 #define write_ldt_entry(dt, entry, low, high)                           \
 296         (paravirt_ops.write_ldt_entry((dt), (entry), (low), (high)))
 297 #define write_gdt_entry(dt, entry, low, high)                           \
 298         (paravirt_ops.write_gdt_entry((dt), (entry), (low), (high)))
 299 #define write_idt_entry(dt, entry, low, high)                           \
 300         (paravirt_ops.write_idt_entry((dt), (entry), (low), (high)))
 301 #define set_iopl_mask(mask) (paravirt_ops.set_iopl_mask(mask))
 302
 303 /* The paravirtualized I/O functions */
 304 static inline void slow_down_io(void) {
 305         paravirt_ops.io_delay();
 306 #ifdef REALLY_SLOW_IO
 307         paravirt_ops.io_delay();
 308         paravirt_ops.io_delay();
 309         paravirt_ops.io_delay();
 310 #endif
 311 }
 312
 313 #ifdef CONFIG_X86_LOCAL_APIC
 314 /*
 315  * Basic functions accessing APICs.
 316  */
 317 static inline void apic_write(unsigned long reg, unsigned long v)
 318 {
 319         paravirt_ops.apic_write(reg,v);
 320 }
 321
 322 static inline void apic_write_atomic(unsigned long reg, unsigned long v)
 323 {
 324         paravirt_ops.apic_write_atomic(reg,v);
 325 }
 326
 327 static inline unsigned long apic_read(unsigned long reg)
 328 {
 329         return paravirt_ops.apic_read(reg);
 330 }
 331
 332 static inline void setup_boot_clock(void)
 333 {
 334         paravirt_ops.setup_boot_clock();
 335 }
 336
 337 static inline void setup_secondary_clock(void)
 338 {
 339         paravirt_ops.setup_secondary_clock();
 340 }
 341 #endif
 342
 343 #ifdef CONFIG_SMP
 344 static inline void startup_ipi_hook(int phys_apicid, unsigned long start_eip,
 345                                     unsigned long start_esp)
 346 {
 347         return paravirt_ops.startup_ipi_hook(phys_apicid, start_eip, start_esp);
 348 }
 349 #endif
 350
 351 #define __flush_tlb() paravirt_ops.flush_tlb_user()
 352 #define __flush_tlb_global() paravirt_ops.flush_tlb_kernel()
 353 #define __flush_tlb_single(addr) paravirt_ops.flush_tlb_single(addr)
 354
 355 #define paravirt_alloc_pt(pfn) paravirt_ops.alloc_pt(pfn)
 356 #define paravirt_release_pt(pfn) paravirt_ops.release_pt(pfn)
 357
 358 #define paravirt_alloc_pd(pfn) paravirt_ops.alloc_pd(pfn)
 359 #define paravirt_alloc_pd_clone(pfn, clonepfn, start, count) \
 360         paravirt_ops.alloc_pd_clone(pfn, clonepfn, start, count)
 361 #define paravirt_release_pd(pfn) paravirt_ops.release_pd(pfn)
 362
 363 static inline void set_pte(pte_t *ptep, pte_t pteval)
 364 {
 365         paravirt_ops.set_pte(ptep, pteval);
 366 }
 367
 368 static inline void set_pte_at(struct mm_struct *mm, u32 addr, pte_t *ptep, pte_t pteval)
 369 {
 370         paravirt_ops.set_pte_at(mm, addr, ptep, pteval);
 371 }
 372
 373 static inline void set_pmd(pmd_t *pmdp, pmd_t pmdval)
 374 {
 375         paravirt_ops.set_pmd(pmdp, pmdval);
 376 }
 377
 378 static inline void pte_update(struct mm_struct *mm, u32 addr, pte_t *ptep)
 379 {
 380         paravirt_ops.pte_update(mm, addr, ptep);
 381 }
 382
 383 static inline void pte_update_defer(struct mm_struct *mm, u32 addr, pte_t *ptep)
 384 {
 385         paravirt_ops.pte_update_defer(mm, addr, ptep);
 386 }
 387
 388 #ifdef CONFIG_X86_PAE
 389 static inline void set_pte_atomic(pte_t *ptep, pte_t pteval)
 390 {
 391         paravirt_ops.set_pte_atomic(ptep, pteval);
 392 }
 393
 394 static inline void set_pte_present(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte)
 395 {
 396         paravirt_ops.set_pte_present(mm, addr, ptep, pte);
 397 }
 398
 399 static inline void set_pud(pud_t *pudp, pud_t pudval)
 400 {
 401         paravirt_ops.set_pud(pudp, pudval);
 402 }
 403
 404 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 405 {
 406         paravirt_ops.pte_clear(mm, addr, ptep);
 407 }
 408
 409 static inline void pmd_clear(pmd_t *pmdp)
 410 {
 411         paravirt_ops.pmd_clear(pmdp);
 412 }
 413 #endif
 414
 415 /* Lazy mode for batching updates / context switch */
 416 #define PARAVIRT_LAZY_NONE 0
 417 #define PARAVIRT_LAZY_MMU  1
 418 #define PARAVIRT_LAZY_CPU  2
 419
 420 #define  __HAVE_ARCH_ENTER_LAZY_CPU_MODE
 421 #define arch_enter_lazy_cpu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_CPU)
 422 #define arch_leave_lazy_cpu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_NONE)
 423
 424 #define  __HAVE_ARCH_ENTER_LAZY_MMU_MODE
 425 #define arch_enter_lazy_mmu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_MMU)
 426 #define arch_leave_lazy_mmu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_NONE)
 427
 428 /* These all sit in the .parainstructions section to tell us what to patch. */
 429 struct paravirt_patch {
 430         u8 *instr;              /* original instructions */
 431         u8 instrtype;           /* type of this instruction */
 432         u8 len;                 /* length of original instruction */
 433         u16 clobbers;           /* what registers you may clobber */
 434 };
 435
 436 #define paravirt_alt(insn_string, typenum, clobber)     \
 437         "771:\n\t" insn_string "\n" "772:\n"            \
 438         ".pushsection .parainstructions,\"a\"\n"        \
 439         "  .long 771b\n"                                \
 440         "  .byte " __stringify(typenum) "\n"            \
 441         "  .byte 772b-771b\n"                           \
 442         "  .short " __stringify(clobber) "\n"           \
 443         ".popsection"
 444
 445 static inline unsigned long __raw_local_save_flags(void)
 446 {
 447         unsigned long f;
 448
 449         __asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
 450                                            "call *%1;"
 451                                            "popl %%edx; popl %%ecx",
 452                                           PARAVIRT_SAVE_FLAGS, CLBR_NONE)
 453                              : "=a"(f): "m"(paravirt_ops.save_fl)
 454                              : "memory", "cc");
 455         return f;
 456 }
 457
 458 static inline void raw_local_irq_restore(unsigned long f)
 459 {
 460         __asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
 461                                            "call *%1;"
 462                                            "popl %%edx; popl %%ecx",
 463                                           PARAVIRT_RESTORE_FLAGS, CLBR_EAX)
 464                              : "=a"(f) : "m" (paravirt_ops.restore_fl), "0"(f)
 465                              : "memory", "cc");
 466 }
 467
 468 static inline void raw_local_irq_disable(void)
 469 {
 470         __asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
 471                                            "call *%0;"
 472                                            "popl %%edx; popl %%ecx",
 473                                           PARAVIRT_IRQ_DISABLE, CLBR_EAX)
 474                              : : "m" (paravirt_ops.irq_disable)
 475                              : "memory", "eax", "cc");
 476 }
 477
 478 static inline void raw_local_irq_enable(void)
 479 {
 480         __asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
 481                                            "call *%0;"
 482                                            "popl %%edx; popl %%ecx",
 483                                           PARAVIRT_IRQ_ENABLE, CLBR_EAX)
 484                              : : "m" (paravirt_ops.irq_enable)
 485                              : "memory", "eax", "cc");
 486 }
 487
 488 static inline unsigned long __raw_local_irq_save(void)
 489 {
 490         unsigned long f;
 491
 492         __asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
 493                                            "call *%1; pushl %%eax;"
 494                                            "call *%2; popl %%eax;"
 495                                            "popl %%edx; popl %%ecx",
 496                                           PARAVIRT_SAVE_FLAGS_IRQ_DISABLE,
 497                                           CLBR_NONE)
 498                              : "=a"(f)
 499                              : "m" (paravirt_ops.save_fl),
 500                                "m" (paravirt_ops.irq_disable)
 501                              : "memory", "cc");
 502         return f;
 503 }
 504
 505 #define CLI_STRING paravirt_alt("pushl %%ecx; pushl %%edx;"             \
 506                      "call *paravirt_ops+%c[irq_disable];"              \
 507                      "popl %%edx; popl %%ecx",                          \
 508                      PARAVIRT_IRQ_DISABLE, CLBR_EAX)
 509
 510 #define STI_STRING paravirt_alt("pushl %%ecx; pushl %%edx;"             \
 511                      "call *paravirt_ops+%c[irq_enable];"               \
 512                      "popl %%edx; popl %%ecx",                          \
 513                      PARAVIRT_IRQ_ENABLE, CLBR_EAX)
 514 #define CLI_STI_CLOBBERS , "%eax"
 515 #define CLI_STI_INPUT_ARGS \
 516         ,                                                               \
 517         [irq_disable] "i" (offsetof(struct paravirt_ops, irq_disable)), \
 518         [irq_enable] "i" (offsetof(struct paravirt_ops, irq_enable))
 519
 520 #else  /* __ASSEMBLY__ */
 521
 522 #define PARA_PATCH(ptype, clobbers, ops)        \
 523 771:;                                           \
 524         ops;                                    \
 525 772:;                                           \
 526         .pushsection .parainstructions,"a";     \
 527          .long 771b;                            \
 528          .byte ptype;                           \
 529          .byte 772b-771b;                       \
 530          .short clobbers;                       \
 531         .popsection
 532
 533 #define INTERRUPT_RETURN                                \
 534         PARA_PATCH(PARAVIRT_INTERRUPT_RETURN, CLBR_ANY, \
 535         jmp *%cs:paravirt_ops+PARAVIRT_iret)
 536
 537 #define DISABLE_INTERRUPTS(clobbers)                    \
 538         PARA_PATCH(PARAVIRT_IRQ_DISABLE, clobbers,      \
 539         pushl %ecx; pushl %edx;                         \
 540         call *paravirt_ops+PARAVIRT_irq_disable;        \
 541         popl %edx; popl %ecx)                           \
 542
 543 #define ENABLE_INTERRUPTS(clobbers)                     \
 544         PARA_PATCH(PARAVIRT_IRQ_ENABLE, clobbers,       \
 545         pushl %ecx; pushl %edx;                         \
 546         call *%cs:paravirt_ops+PARAVIRT_irq_enable;     \
 547         popl %edx; popl %ecx)
 548
 549 #define ENABLE_INTERRUPTS_SYSEXIT                       \
 550         PARA_PATCH(PARAVIRT_STI_SYSEXIT, CLBR_ANY,      \
 551         jmp *%cs:paravirt_ops+PARAVIRT_irq_enable_sysexit)
 552
 553 #define GET_CR0_INTO_EAX                        \
 554         call *paravirt_ops+PARAVIRT_read_cr0
 555
 556 #endif /* __ASSEMBLY__ */
 557 #endif /* CONFIG_PARAVIRT */
 558 #endif  /* __ASM_PARAVIRT_H */