arch/x86/include/asm/processor.h

   1 #ifndef _ASM_X86_PROCESSOR_H
   2 #define _ASM_X86_PROCESSOR_H
   3
   4 #include <asm/processor-flags.h>
   5
   6 /* Forward declaration, a strange C thing */
   7 struct task_struct;
   8 struct mm_struct;
   9 struct vm86;
  10
  11 #include <asm/math_emu.h>
  12 #include <asm/segment.h>
  13 #include <asm/types.h>
  14 #include <uapi/asm/sigcontext.h>
  15 #include <asm/current.h>
  16 #include <asm/cpufeatures.h>
  17 #include <asm/page.h>
  18 #include <asm/pgtable_types.h>
  19 #include <asm/percpu.h>
  20 #include <asm/msr.h>
  21 #include <asm/desc_defs.h>
  22 #include <asm/nops.h>
  23 #include <asm/special_insns.h>
  24 #include <asm/fpu/types.h>
  25
  26 #include <linux/personality.h>
  27 #include <linux/cache.h>
  28 #include <linux/threads.h>
  29 #include <linux/math64.h>
  30 #include <linux/err.h>
  31 #include <linux/irqflags.h>
  32
  33 /*
  34  * We handle most unaligned accesses in hardware.  On the other hand
  35  * unaligned DMA can be quite expensive on some Nehalem processors.
  36  *
  37  * Based on this we disable the IP header alignment in network drivers.
  38  */
  39 #define NET_IP_ALIGN    0
  40
  41 #define HBP_NUM 4
  42 /*
  43  * Default implementation of macro that returns current
  44  * instruction pointer ("program counter").
  45  */
  46 static inline void *current_text_addr(void)
  47 {
  48         void *pc;
  49
  50         asm volatile("mov $1f, %0; 1:":"=r" (pc));
  51
  52         return pc;
  53 }
  54
  55 /*
  56  * These alignment constraints are for performance in the vSMP case,
  57  * but in the task_struct case we must also meet hardware imposed
  58  * alignment requirements of the FPU state:
  59  */
  60 #ifdef CONFIG_X86_VSMP
  61 # define ARCH_MIN_TASKALIGN             (1 << INTERNODE_CACHE_SHIFT)
  62 # define ARCH_MIN_MMSTRUCT_ALIGN        (1 << INTERNODE_CACHE_SHIFT)
  63 #else
  64 # define ARCH_MIN_TASKALIGN             __alignof__(union fpregs_state)
  65 # define ARCH_MIN_MMSTRUCT_ALIGN        0
  66 #endif
  67
  68 enum tlb_infos {
  69         ENTRIES,
  70         NR_INFO
  71 };
  72
  73 extern u16 __read_mostly tlb_lli_4k[NR_INFO];
  74 extern u16 __read_mostly tlb_lli_2m[NR_INFO];
  75 extern u16 __read_mostly tlb_lli_4m[NR_INFO];
  76 extern u16 __read_mostly tlb_lld_4k[NR_INFO];
  77 extern u16 __read_mostly tlb_lld_2m[NR_INFO];
  78 extern u16 __read_mostly tlb_lld_4m[NR_INFO];
  79 extern u16 __read_mostly tlb_lld_1g[NR_INFO];
  80
  81 /*
  82  *  CPU type and hardware bug flags. Kept separately for each CPU.
  83  *  Members of this structure are referenced in head.S, so think twice
  84  *  before touching them. [mj]
  85  */
  86
  87 struct cpuinfo_x86 {
  88         __u8                    x86;            /* CPU family */
  89         __u8                    x86_vendor;     /* CPU vendor */
  90         __u8                    x86_model;
  91         __u8                    x86_mask;
  92 #ifdef CONFIG_X86_32
  93         char                    wp_works_ok;    /* It doesn't on 386's */
  94
  95         /* Problems on some 486Dx4's and old 386's: */
  96         char                    rfu;
  97         char                    pad0;
  98         char                    pad1;
  99 #else
 100         /* Number of 4K pages in DTLB/ITLB combined(in pages): */
 101         int                     x86_tlbsize;
 102 #endif
 103         __u8                    x86_virt_bits;
 104         __u8                    x86_phys_bits;
 105         /* CPUID returned core id bits: */
 106         __u8                    x86_coreid_bits;
 107         /* Max extended CPUID function supported: */
 108         __u32                   extended_cpuid_level;
 109         /* Maximum supported CPUID level, -1=no CPUID: */
 110         int                     cpuid_level;
 111         __u32                   x86_capability[NCAPINTS + NBUGINTS];
 112         char                    x86_vendor_id[16];
 113         char                    x86_model_id[64];
 114         /* in KB - valid for CPUS which support this call: */
 115         int                     x86_cache_size;
 116         int                     x86_cache_alignment;    /* In bytes */
 117         /* Cache QoS architectural values: */
 118         int                     x86_cache_max_rmid;     /* max index */
 119         int                     x86_cache_occ_scale;    /* scale to bytes */
 120         int                     x86_power;
 121         unsigned long           loops_per_jiffy;
 122         /* cpuid returned max cores value: */
 123         u16                      x86_max_cores;
 124         u16                     apicid;
 125         u16                     initial_apicid;
 126         u16                     x86_clflush_size;
 127         /* number of cores as seen by the OS: */
 128         u16                     booted_cores;
 129         /* Physical processor id: */
 130         u16                     phys_proc_id;
 131         /* Logical processor id: */
 132         u16                     logical_proc_id;
 133         /* Core id: */
 134         u16                     cpu_core_id;
 135         /* Index into per_cpu list: */
 136         u16                     cpu_index;
 137         u32                     microcode;
 138 };
 139
 140 #define X86_VENDOR_INTEL        0
 141 #define X86_VENDOR_CYRIX        1
 142 #define X86_VENDOR_AMD          2
 143 #define X86_VENDOR_UMC          3
 144 #define X86_VENDOR_CENTAUR      5
 145 #define X86_VENDOR_TRANSMETA    7
 146 #define X86_VENDOR_NSC          8
 147 #define X86_VENDOR_NUM          9
 148
 149 #define X86_VENDOR_UNKNOWN      0xff
 150
 151 /*
 152  * capabilities of CPUs
 153  */
 154 extern struct cpuinfo_x86       boot_cpu_data;
 155 extern struct cpuinfo_x86       new_cpu_data;
 156
 157 extern struct tss_struct        doublefault_tss;
 158 extern __u32                    cpu_caps_cleared[NCAPINTS];
 159 extern __u32                    cpu_caps_set[NCAPINTS];
 160
 161 #ifdef CONFIG_SMP
 162 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
 163 #define cpu_data(cpu)           per_cpu(cpu_info, cpu)
 164 #else
 165 #define cpu_info                boot_cpu_data
 166 #define cpu_data(cpu)           boot_cpu_data
 167 #endif
 168
 169 extern const struct seq_operations cpuinfo_op;
 170
 171 #define cache_line_size()       (boot_cpu_data.x86_cache_alignment)
 172
 173 extern void cpu_detect(struct cpuinfo_x86 *c);
 174
 175 extern void early_cpu_init(void);
 176 extern void identify_boot_cpu(void);
 177 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
 178 extern void print_cpu_info(struct cpuinfo_x86 *);
 179 void print_cpu_msr(struct cpuinfo_x86 *);
 180 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
 181 extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
 182 extern void init_amd_cacheinfo(struct cpuinfo_x86 *c);
 183
 184 extern void detect_extended_topology(struct cpuinfo_x86 *c);
 185 extern void detect_ht(struct cpuinfo_x86 *c);
 186
 187 #ifdef CONFIG_X86_32
 188 extern int have_cpuid_p(void);
 189 #else
 190 static inline int have_cpuid_p(void)
 191 {
 192         return 1;
 193 }
 194 #endif
 195 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
 196                                 unsigned int *ecx, unsigned int *edx)
 197 {
 198         /* ecx is often an input as well as an output. */
 199         asm volatile("cpuid"
 200             : "=a" (*eax),
 201               "=b" (*ebx),
 202               "=c" (*ecx),
 203               "=d" (*edx)
 204             : "0" (*eax), "2" (*ecx)
 205             : "memory");
 206 }
 207
 208 static inline void load_cr3(pgd_t *pgdir)
 209 {
 210         write_cr3(__pa(pgdir));
 211 }
 212
 213 #ifdef CONFIG_X86_32
 214 /* This is the TSS defined by the hardware. */
 215 struct x86_hw_tss {
 216         unsigned short          back_link, __blh;
 217         unsigned long           sp0;
 218         unsigned short          ss0, __ss0h;
 219         unsigned long           sp1;
 220
 221         /*
 222          * We don't use ring 1, so ss1 is a convenient scratch space in
 223          * the same cacheline as sp0.  We use ss1 to cache the value in
 224          * MSR_IA32_SYSENTER_CS.  When we context switch
 225          * MSR_IA32_SYSENTER_CS, we first check if the new value being
 226          * written matches ss1, and, if it's not, then we wrmsr the new
 227          * value and update ss1.
 228          *
 229          * The only reason we context switch MSR_IA32_SYSENTER_CS is
 230          * that we set it to zero in vm86 tasks to avoid corrupting the
 231          * stack if we were to go through the sysenter path from vm86
 232          * mode.
 233          */
 234         unsigned short          ss1;    /* MSR_IA32_SYSENTER_CS */
 235
 236         unsigned short          __ss1h;
 237         unsigned long           sp2;
 238         unsigned short          ss2, __ss2h;
 239         unsigned long           __cr3;
 240         unsigned long           ip;
 241         unsigned long           flags;
 242         unsigned long           ax;
 243         unsigned long           cx;
 244         unsigned long           dx;
 245         unsigned long           bx;
 246         unsigned long           sp;
 247         unsigned long           bp;
 248         unsigned long           si;
 249         unsigned long           di;
 250         unsigned short          es, __esh;
 251         unsigned short          cs, __csh;
 252         unsigned short          ss, __ssh;
 253         unsigned short          ds, __dsh;
 254         unsigned short          fs, __fsh;
 255         unsigned short          gs, __gsh;
 256         unsigned short          ldt, __ldth;
 257         unsigned short          trace;
 258         unsigned short          io_bitmap_base;
 259
 260 } __attribute__((packed));
 261 #else
 262 struct x86_hw_tss {
 263         u32                     reserved1;
 264         u64                     sp0;
 265         u64                     sp1;
 266         u64                     sp2;
 267         u64                     reserved2;
 268         u64                     ist[7];
 269         u32                     reserved3;
 270         u32                     reserved4;
 271         u16                     reserved5;
 272         u16                     io_bitmap_base;
 273
 274 } __attribute__((packed)) ____cacheline_aligned;
 275 #endif
 276
 277 /*
 278  * IO-bitmap sizes:
 279  */
 280 #define IO_BITMAP_BITS                  65536
 281 #define IO_BITMAP_BYTES                 (IO_BITMAP_BITS/8)
 282 #define IO_BITMAP_LONGS                 (IO_BITMAP_BYTES/sizeof(long))
 283 #define IO_BITMAP_OFFSET                offsetof(struct tss_struct, io_bitmap)
 284 #define INVALID_IO_BITMAP_OFFSET        0x8000
 285
 286 struct tss_struct {
 287         /*
 288          * The hardware state:
 289          */
 290         struct x86_hw_tss       x86_tss;
 291
 292         /*
 293          * The extra 1 is there because the CPU will access an
 294          * additional byte beyond the end of the IO permission
 295          * bitmap. The extra byte must be all 1 bits, and must
 296          * be within the limit.
 297          */
 298         unsigned long           io_bitmap[IO_BITMAP_LONGS + 1];
 299
 300 #ifdef CONFIG_X86_32
 301         /*
 302          * Space for the temporary SYSENTER stack.
 303          */
 304         unsigned long           SYSENTER_stack_canary;
 305         unsigned long           SYSENTER_stack[64];
 306 #endif
 307
 308 } ____cacheline_aligned;
 309
 310 DECLARE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss);
 311
 312 #ifdef CONFIG_X86_32
 313 DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
 314 #endif
 315
 316 /*
 317  * Save the original ist values for checking stack pointers during debugging
 318  */
 319 struct orig_ist {
 320         unsigned long           ist[7];
 321 };
 322
 323 #ifdef CONFIG_X86_64
 324 DECLARE_PER_CPU(struct orig_ist, orig_ist);
 325
 326 union irq_stack_union {
 327         char irq_stack[IRQ_STACK_SIZE];
 328         /*
 329          * GCC hardcodes the stack canary as %gs:40.  Since the
 330          * irq_stack is the object at %gs:0, we reserve the bottom
 331          * 48 bytes of the irq stack for the canary.
 332          */
 333         struct {
 334                 char gs_base[40];
 335                 unsigned long stack_canary;
 336         };
 337 };
 338
 339 DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __visible;
 340 DECLARE_INIT_PER_CPU(irq_stack_union);
 341
 342 DECLARE_PER_CPU(char *, irq_stack_ptr);
 343 DECLARE_PER_CPU(unsigned int, irq_count);
 344 extern asmlinkage void ignore_sysret(void);
 345 #else   /* X86_64 */
 346 #ifdef CONFIG_CC_STACKPROTECTOR
 347 /*
 348  * Make sure stack canary segment base is cached-aligned:
 349  *   "For Intel Atom processors, avoid non zero segment base address
 350  *    that is not aligned to cache line boundary at all cost."
 351  * (Optim Ref Manual Assembly/Compiler Coding Rule 15.)
 352  */
 353 struct stack_canary {
 354         char __pad[20];         /* canary at %gs:20 */
 355         unsigned long canary;
 356 };
 357 DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
 358 #endif
 359 /*
 360  * per-CPU IRQ handling stacks
 361  */
 362 struct irq_stack {
 363         u32                     stack[THREAD_SIZE/sizeof(u32)];
 364 } __aligned(THREAD_SIZE);
 365
 366 DECLARE_PER_CPU(struct irq_stack *, hardirq_stack);
 367 DECLARE_PER_CPU(struct irq_stack *, softirq_stack);
 368 #endif  /* X86_64 */
 369
 370 extern unsigned int fpu_kernel_xstate_size;
 371 extern unsigned int fpu_user_xstate_size;
 372
 373 struct perf_event;
 374
 375 typedef struct {
 376         unsigned long           seg;
 377 } mm_segment_t;
 378
 379 struct thread_struct {
 380         /* Cached TLS descriptors: */
 381         struct desc_struct      tls_array[GDT_ENTRY_TLS_ENTRIES];
 382         unsigned long           sp0;
 383         unsigned long           sp;
 384 #ifdef CONFIG_X86_32
 385         unsigned long           sysenter_cs;
 386 #else
 387         unsigned short          es;
 388         unsigned short          ds;
 389         unsigned short          fsindex;
 390         unsigned short          gsindex;
 391 #endif
 392 #ifdef CONFIG_X86_32
 393         unsigned long           ip;
 394 #endif
 395 #ifdef CONFIG_X86_64
 396         unsigned long           fsbase;
 397         unsigned long           gsbase;
 398 #else
 399         /*
 400          * XXX: this could presumably be unsigned short.  Alternatively,
 401          * 32-bit kernels could be taught to use fsindex instead.
 402          */
 403         unsigned long fs;
 404         unsigned long gs;
 405 #endif
 406
 407         /* Save middle states of ptrace breakpoints */
 408         struct perf_event       *ptrace_bps[HBP_NUM];
 409         /* Debug status used for traps, single steps, etc... */
 410         unsigned long           debugreg6;
 411         /* Keep track of the exact dr7 value set by the user */
 412         unsigned long           ptrace_dr7;
 413         /* Fault info: */
 414         unsigned long           cr2;
 415         unsigned long           trap_nr;
 416         unsigned long           error_code;
 417 #ifdef CONFIG_VM86
 418         /* Virtual 86 mode info */
 419         struct vm86             *vm86;
 420 #endif
 421         /* IO permissions: */
 422         unsigned long           *io_bitmap_ptr;
 423         unsigned long           iopl;
 424         /* Max allowed port in the bitmap, in bytes: */
 425         unsigned                io_bitmap_max;
 426
 427         mm_segment_t            addr_limit;
 428
 429         unsigned int            sig_on_uaccess_err:1;
 430         unsigned int            uaccess_err:1;  /* uaccess failed */
 431
 432         /* Floating point and extended processor state */
 433         struct fpu              fpu;
 434         /*
 435          * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
 436          * the end.
 437          */
 438 };
 439
 440 /*
 441  * Set IOPL bits in EFLAGS from given mask
 442  */
 443 static inline void native_set_iopl_mask(unsigned mask)
 444 {
 445 #ifdef CONFIG_X86_32
 446         unsigned int reg;
 447
 448         asm volatile ("pushfl;"
 449                       "popl %0;"
 450                       "andl %1, %0;"
 451                       "orl %2, %0;"
 452                       "pushl %0;"
 453                       "popfl"
 454                       : "=&r" (reg)
 455                       : "i" (~X86_EFLAGS_IOPL), "r" (mask));
 456 #endif
 457 }
 458
 459 static inline void
 460 native_load_sp0(struct tss_struct *tss, struct thread_struct *thread)
 461 {
 462         tss->x86_tss.sp0 = thread->sp0;
 463 #ifdef CONFIG_X86_32
 464         /* Only happens when SEP is enabled, no need to test "SEP"arately: */
 465         if (unlikely(tss->x86_tss.ss1 != thread->sysenter_cs)) {
 466                 tss->x86_tss.ss1 = thread->sysenter_cs;
 467                 wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
 468         }
 469 #endif
 470 }
 471
 472 static inline void native_swapgs(void)
 473 {
 474 #ifdef CONFIG_X86_64
 475         asm volatile("swapgs" ::: "memory");
 476 #endif
 477 }
 478
 479 static inline unsigned long current_top_of_stack(void)
 480 {
 481 #ifdef CONFIG_X86_64
 482         return this_cpu_read_stable(cpu_tss.x86_tss.sp0);
 483 #else
 484         /* sp0 on x86_32 is special in and around vm86 mode. */
 485         return this_cpu_read_stable(cpu_current_top_of_stack);
 486 #endif
 487 }
 488
 489 #ifdef CONFIG_PARAVIRT
 490 #include <asm/paravirt.h>
 491 #else
 492 #define __cpuid                 native_cpuid
 493
 494 static inline void load_sp0(struct tss_struct *tss,
 495                             struct thread_struct *thread)
 496 {
 497         native_load_sp0(tss, thread);
 498 }
 499
 500 #define set_iopl_mask native_set_iopl_mask
 501 #endif /* CONFIG_PARAVIRT */
 502
 503 /* Free all resources held by a thread. */
 504 extern void release_thread(struct task_struct *);
 505
 506 unsigned long get_wchan(struct task_struct *p);
 507
 508 /*
 509  * Generic CPUID function
 510  * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
 511  * resulting in stale register contents being returned.
 512  */
 513 static inline void cpuid(unsigned int op,
 514                          unsigned int *eax, unsigned int *ebx,
 515                          unsigned int *ecx, unsigned int *edx)
 516 {
 517         *eax = op;
 518         *ecx = 0;
 519         __cpuid(eax, ebx, ecx, edx);
 520 }
 521
 522 /* Some CPUID calls want 'count' to be placed in ecx */
 523 static inline void cpuid_count(unsigned int op, int count,
 524                                unsigned int *eax, unsigned int *ebx,
 525                                unsigned int *ecx, unsigned int *edx)
 526 {
 527         *eax = op;
 528         *ecx = count;
 529         __cpuid(eax, ebx, ecx, edx);
 530 }
 531
 532 /*
 533  * CPUID functions returning a single datum
 534  */
 535 static inline unsigned int cpuid_eax(unsigned int op)
 536 {
 537         unsigned int eax, ebx, ecx, edx;
 538
 539         cpuid(op, &eax, &ebx, &ecx, &edx);
 540
 541         return eax;
 542 }
 543
 544 static inline unsigned int cpuid_ebx(unsigned int op)
 545 {
 546         unsigned int eax, ebx, ecx, edx;
 547
 548         cpuid(op, &eax, &ebx, &ecx, &edx);
 549
 550         return ebx;
 551 }
 552
 553 static inline unsigned int cpuid_ecx(unsigned int op)
 554 {
 555         unsigned int eax, ebx, ecx, edx;
 556
 557         cpuid(op, &eax, &ebx, &ecx, &edx);
 558
 559         return ecx;
 560 }
 561
 562 static inline unsigned int cpuid_edx(unsigned int op)
 563 {
 564         unsigned int eax, ebx, ecx, edx;
 565
 566         cpuid(op, &eax, &ebx, &ecx, &edx);
 567
 568         return edx;
 569 }
 570
 571 /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
 572 static __always_inline void rep_nop(void)
 573 {
 574         asm volatile("rep; nop" ::: "memory");
 575 }
 576
 577 static __always_inline void cpu_relax(void)
 578 {
 579         rep_nop();
 580 }
 581
 582 #define cpu_relax_lowlatency() cpu_relax()
 583
 584 /* Stop speculative execution and prefetching of modified code. */
 585 static inline void sync_core(void)
 586 {
 587         int tmp;
 588
 589 #ifdef CONFIG_M486
 590         /*
 591          * Do a CPUID if available, otherwise do a jump.  The jump
 592          * can conveniently enough be the jump around CPUID.
 593          */
 594         asm volatile("cmpl %2,%1\n\t"
 595                      "jl 1f\n\t"
 596                      "cpuid\n"
 597                      "1:"
 598                      : "=a" (tmp)
 599                      : "rm" (boot_cpu_data.cpuid_level), "ri" (0), "0" (1)
 600                      : "ebx", "ecx", "edx", "memory");
 601 #else
 602         /*
 603          * CPUID is a barrier to speculative execution.
 604          * Prefetched instructions are automatically
 605          * invalidated when modified.
 606          */
 607         asm volatile("cpuid"
 608                      : "=a" (tmp)
 609                      : "0" (1)
 610                      : "ebx", "ecx", "edx", "memory");
 611 #endif
 612 }
 613
 614 extern void select_idle_routine(const struct cpuinfo_x86 *c);
 615 extern void init_amd_e400_c1e_mask(void);
 616
 617 extern unsigned long            boot_option_idle_override;
 618 extern bool                     amd_e400_c1e_detected;
 619
 620 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
 621                          IDLE_POLL};
 622
 623 extern void enable_sep_cpu(void);
 624 extern int sysenter_setup(void);
 625
 626 extern void early_trap_init(void);
 627 void early_trap_pf_init(void);
 628
 629 /* Defined in head.S */
 630 extern struct desc_ptr          early_gdt_descr;
 631
 632 extern void cpu_set_gdt(int);
 633 extern void switch_to_new_gdt(int);
 634 extern void load_percpu_segment(int);
 635 extern void cpu_init(void);
 636
 637 static inline unsigned long get_debugctlmsr(void)
 638 {
 639         unsigned long debugctlmsr = 0;
 640
 641 #ifndef CONFIG_X86_DEBUGCTLMSR
 642         if (boot_cpu_data.x86 < 6)
 643                 return 0;
 644 #endif
 645         rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
 646
 647         return debugctlmsr;
 648 }
 649
 650 static inline void update_debugctlmsr(unsigned long debugctlmsr)
 651 {
 652 #ifndef CONFIG_X86_DEBUGCTLMSR
 653         if (boot_cpu_data.x86 < 6)
 654                 return;
 655 #endif
 656         wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
 657 }
 658
 659 extern void set_task_blockstep(struct task_struct *task, bool on);
 660
 661 /* Boot loader type from the setup header: */
 662 extern int                      bootloader_type;
 663 extern int                      bootloader_version;
 664
 665 extern char                     ignore_fpu_irq;
 666
 667 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
 668 #define ARCH_HAS_PREFETCHW
 669 #define ARCH_HAS_SPINLOCK_PREFETCH
 670
 671 #ifdef CONFIG_X86_32
 672 # define BASE_PREFETCH          ""
 673 # define ARCH_HAS_PREFETCH
 674 #else
 675 # define BASE_PREFETCH          "prefetcht0 %P1"
 676 #endif
 677
 678 /*
 679  * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
 680  *
 681  * It's not worth to care about 3dnow prefetches for the K6
 682  * because they are microcoded there and very slow.
 683  */
 684 static inline void prefetch(const void *x)
 685 {
 686         alternative_input(BASE_PREFETCH, "prefetchnta %P1",
 687                           X86_FEATURE_XMM,
 688                           "m" (*(const char *)x));
 689 }
 690
 691 /*
 692  * 3dnow prefetch to get an exclusive cache line.
 693  * Useful for spinlocks to avoid one state transition in the
 694  * cache coherency protocol:
 695  */
 696 static inline void prefetchw(const void *x)
 697 {
 698         alternative_input(BASE_PREFETCH, "prefetchw %P1",
 699                           X86_FEATURE_3DNOWPREFETCH,
 700                           "m" (*(const char *)x));
 701 }
 702
 703 static inline void spin_lock_prefetch(const void *x)
 704 {
 705         prefetchw(x);
 706 }
 707
 708 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
 709                            TOP_OF_KERNEL_STACK_PADDING)
 710
 711 #ifdef CONFIG_X86_32
 712 /*
 713  * User space process size: 3GB (default).
 714  */
 715 #define TASK_SIZE               PAGE_OFFSET
 716 #define TASK_SIZE_MAX           TASK_SIZE
 717 #define STACK_TOP               TASK_SIZE
 718 #define STACK_TOP_MAX           STACK_TOP
 719
 720 #define INIT_THREAD  {                                                    \
 721         .sp0                    = TOP_OF_INIT_STACK,                      \
 722         .sysenter_cs            = __KERNEL_CS,                            \
 723         .io_bitmap_ptr          = NULL,                                   \
 724         .addr_limit             = KERNEL_DS,                              \
 725 }
 726
 727 extern unsigned long thread_saved_pc(struct task_struct *tsk);
 728
 729 /*
 730  * TOP_OF_KERNEL_STACK_PADDING reserves 8 bytes on top of the ring0 stack.
 731  * This is necessary to guarantee that the entire "struct pt_regs"
 732  * is accessible even if the CPU haven't stored the SS/ESP registers
 733  * on the stack (interrupt gate does not save these registers
 734  * when switching to the same priv ring).
 735  * Therefore beware: accessing the ss/esp fields of the
 736  * "struct pt_regs" is possible, but they may contain the
 737  * completely wrong values.
 738  */
 739 #define task_pt_regs(task) \
 740 ({                                                                      \
 741         unsigned long __ptr = (unsigned long)task_stack_page(task);     \
 742         __ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;             \
 743         ((struct pt_regs *)__ptr) - 1;                                  \
 744 })
 745
 746 #define KSTK_ESP(task)          (task_pt_regs(task)->sp)
 747
 748 #else
 749 /*
 750  * User space process size. 47bits minus one guard page.  The guard
 751  * page is necessary on Intel CPUs: if a SYSCALL instruction is at
 752  * the highest possible canonical userspace address, then that
 753  * syscall will enter the kernel with a non-canonical return
 754  * address, and SYSRET will explode dangerously.  We avoid this
 755  * particular problem by preventing anything from being mapped
 756  * at the maximum canonical address.
 757  */
 758 #define TASK_SIZE_MAX   ((1UL << 47) - PAGE_SIZE)
 759
 760 /* This decides where the kernel will search for a free chunk of vm
 761  * space during mmap's.
 762  */
 763 #define IA32_PAGE_OFFSET        ((current->personality & ADDR_LIMIT_3GB) ? \
 764                                         0xc0000000 : 0xFFFFe000)
 765
 766 #define TASK_SIZE               (test_thread_flag(TIF_ADDR32) ? \
 767                                         IA32_PAGE_OFFSET : TASK_SIZE_MAX)
 768 #define TASK_SIZE_OF(child)     ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
 769                                         IA32_PAGE_OFFSET : TASK_SIZE_MAX)
 770
 771 #define STACK_TOP               TASK_SIZE
 772 #define STACK_TOP_MAX           TASK_SIZE_MAX
 773
 774 #define INIT_THREAD  {                                          \
 775         .sp0                    = TOP_OF_INIT_STACK,            \
 776         .addr_limit             = KERNEL_DS,                    \
 777 }
 778
 779 /*
 780  * Return saved PC of a blocked thread.
 781  * What is this good for? it will be always the scheduler or ret_from_fork.
 782  */
 783 #define thread_saved_pc(t)      READ_ONCE_NOCHECK(*(unsigned long *)((t)->thread.sp - 8))
 784
 785 #define task_pt_regs(tsk)       ((struct pt_regs *)(tsk)->thread.sp0 - 1)
 786 extern unsigned long KSTK_ESP(struct task_struct *task);
 787
 788 #endif /* CONFIG_X86_64 */
 789
 790 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
 791                                                unsigned long new_sp);
 792
 793 /*
 794  * This decides where the kernel will search for a free chunk of vm
 795  * space during mmap's.
 796  */
 797 #define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 3))
 798
 799 #define KSTK_EIP(task)          (task_pt_regs(task)->ip)
 800
 801 /* Get/set a process' ability to use the timestamp counter instruction */
 802 #define GET_TSC_CTL(adr)        get_tsc_mode((adr))
 803 #define SET_TSC_CTL(val)        set_tsc_mode((val))
 804
 805 extern int get_tsc_mode(unsigned long adr);
 806 extern int set_tsc_mode(unsigned int val);
 807
 808 /* Register/unregister a process' MPX related resource */
 809 #define MPX_ENABLE_MANAGEMENT() mpx_enable_management()
 810 #define MPX_DISABLE_MANAGEMENT()        mpx_disable_management()
 811
 812 #ifdef CONFIG_X86_INTEL_MPX
 813 extern int mpx_enable_management(void);
 814 extern int mpx_disable_management(void);
 815 #else
 816 static inline int mpx_enable_management(void)
 817 {
 818         return -EINVAL;
 819 }
 820 static inline int mpx_disable_management(void)
 821 {
 822         return -EINVAL;
 823 }
 824 #endif /* CONFIG_X86_INTEL_MPX */
 825
 826 extern u16 amd_get_nb_id(int cpu);
 827 extern u32 amd_get_nodes_per_socket(void);
 828
 829 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
 830 {
 831         uint32_t base, eax, signature[3];
 832
 833         for (base = 0x40000000; base < 0x40010000; base += 0x100) {
 834                 cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
 835
 836                 if (!memcmp(sig, signature, 12) &&
 837                     (leaves == 0 || ((eax - base) >= leaves)))
 838                         return base;
 839         }
 840
 841         return 0;
 842 }
 843
 844 extern unsigned long arch_align_stack(unsigned long sp);
 845 extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
 846
 847 void default_idle(void);
 848 #ifdef  CONFIG_XEN
 849 bool xen_set_default_idle(void);
 850 #else
 851 #define xen_set_default_idle 0
 852 #endif
 853
 854 void stop_this_cpu(void *dummy);
 855 void df_debug(struct pt_regs *regs, long error_code);
 856 #endif /* _ASM_X86_PROCESSOR_H */