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