linux/arch/x86/include/asm/processor.h
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   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _ASM_X86_PROCESSOR_H
   3#define _ASM_X86_PROCESSOR_H
   4
   5#include <asm/processor-flags.h>
   6
   7/* Forward declaration, a strange C thing */
   8struct task_struct;
   9struct mm_struct;
  10struct io_bitmap;
  11struct vm86;
  12
  13#include <asm/math_emu.h>
  14#include <asm/segment.h>
  15#include <asm/types.h>
  16#include <uapi/asm/sigcontext.h>
  17#include <asm/current.h>
  18#include <asm/cpufeatures.h>
  19#include <asm/page.h>
  20#include <asm/pgtable_types.h>
  21#include <asm/percpu.h>
  22#include <asm/msr.h>
  23#include <asm/desc_defs.h>
  24#include <asm/nops.h>
  25#include <asm/special_insns.h>
  26#include <asm/fpu/types.h>
  27#include <asm/unwind_hints.h>
  28#include <asm/vmxfeatures.h>
  29#include <asm/vdso/processor.h>
  30
  31#include <linux/personality.h>
  32#include <linux/cache.h>
  33#include <linux/threads.h>
  34#include <linux/math64.h>
  35#include <linux/err.h>
  36#include <linux/irqflags.h>
  37#include <linux/mem_encrypt.h>
  38
  39/*
  40 * We handle most unaligned accesses in hardware.  On the other hand
  41 * unaligned DMA can be quite expensive on some Nehalem processors.
  42 *
  43 * Based on this we disable the IP header alignment in network drivers.
  44 */
  45#define NET_IP_ALIGN    0
  46
  47#define HBP_NUM 4
  48
  49/*
  50 * These alignment constraints are for performance in the vSMP case,
  51 * but in the task_struct case we must also meet hardware imposed
  52 * alignment requirements of the FPU state:
  53 */
  54#ifdef CONFIG_X86_VSMP
  55# define ARCH_MIN_TASKALIGN             (1 << INTERNODE_CACHE_SHIFT)
  56# define ARCH_MIN_MMSTRUCT_ALIGN        (1 << INTERNODE_CACHE_SHIFT)
  57#else
  58# define ARCH_MIN_TASKALIGN             __alignof__(union fpregs_state)
  59# define ARCH_MIN_MMSTRUCT_ALIGN        0
  60#endif
  61
  62enum tlb_infos {
  63        ENTRIES,
  64        NR_INFO
  65};
  66
  67extern u16 __read_mostly tlb_lli_4k[NR_INFO];
  68extern u16 __read_mostly tlb_lli_2m[NR_INFO];
  69extern u16 __read_mostly tlb_lli_4m[NR_INFO];
  70extern u16 __read_mostly tlb_lld_4k[NR_INFO];
  71extern u16 __read_mostly tlb_lld_2m[NR_INFO];
  72extern u16 __read_mostly tlb_lld_4m[NR_INFO];
  73extern u16 __read_mostly tlb_lld_1g[NR_INFO];
  74
  75/*
  76 *  CPU type and hardware bug flags. Kept separately for each CPU.
  77 *  Members of this structure are referenced in head_32.S, so think twice
  78 *  before touching them. [mj]
  79 */
  80
  81struct cpuinfo_x86 {
  82        __u8                    x86;            /* CPU family */
  83        __u8                    x86_vendor;     /* CPU vendor */
  84        __u8                    x86_model;
  85        __u8                    x86_stepping;
  86#ifdef CONFIG_X86_64
  87        /* Number of 4K pages in DTLB/ITLB combined(in pages): */
  88        int                     x86_tlbsize;
  89#endif
  90#ifdef CONFIG_X86_VMX_FEATURE_NAMES
  91        __u32                   vmx_capability[NVMXINTS];
  92#endif
  93        __u8                    x86_virt_bits;
  94        __u8                    x86_phys_bits;
  95        /* CPUID returned core id bits: */
  96        __u8                    x86_coreid_bits;
  97        __u8                    cu_id;
  98        /* Max extended CPUID function supported: */
  99        __u32                   extended_cpuid_level;
 100        /* Maximum supported CPUID level, -1=no CPUID: */
 101        int                     cpuid_level;
 102        /*
 103         * Align to size of unsigned long because the x86_capability array
 104         * is passed to bitops which require the alignment. Use unnamed
 105         * union to enforce the array is aligned to size of unsigned long.
 106         */
 107        union {
 108                __u32           x86_capability[NCAPINTS + NBUGINTS];
 109                unsigned long   x86_capability_alignment;
 110        };
 111        char                    x86_vendor_id[16];
 112        char                    x86_model_id[64];
 113        /* in KB - valid for CPUS which support this call: */
 114        unsigned int            x86_cache_size;
 115        int                     x86_cache_alignment;    /* In bytes */
 116        /* Cache QoS architectural values, valid only on the BSP: */
 117        int                     x86_cache_max_rmid;     /* max index */
 118        int                     x86_cache_occ_scale;    /* scale to bytes */
 119        int                     x86_cache_mbm_width_offset;
 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        u16                     cpu_die_id;
 136        u16                     logical_die_id;
 137        /* Index into per_cpu list: */
 138        u16                     cpu_index;
 139        u32                     microcode;
 140        /* Address space bits used by the cache internally */
 141        u8                      x86_cache_bits;
 142        unsigned                initialized : 1;
 143} __randomize_layout;
 144
 145struct cpuid_regs {
 146        u32 eax, ebx, ecx, edx;
 147};
 148
 149enum cpuid_regs_idx {
 150        CPUID_EAX = 0,
 151        CPUID_EBX,
 152        CPUID_ECX,
 153        CPUID_EDX,
 154};
 155
 156#define X86_VENDOR_INTEL        0
 157#define X86_VENDOR_CYRIX        1
 158#define X86_VENDOR_AMD          2
 159#define X86_VENDOR_UMC          3
 160#define X86_VENDOR_CENTAUR      5
 161#define X86_VENDOR_TRANSMETA    7
 162#define X86_VENDOR_NSC          8
 163#define X86_VENDOR_HYGON        9
 164#define X86_VENDOR_ZHAOXIN      10
 165#define X86_VENDOR_NUM          11
 166
 167#define X86_VENDOR_UNKNOWN      0xff
 168
 169/*
 170 * capabilities of CPUs
 171 */
 172extern struct cpuinfo_x86       boot_cpu_data;
 173extern struct cpuinfo_x86       new_cpu_data;
 174
 175extern __u32                    cpu_caps_cleared[NCAPINTS + NBUGINTS];
 176extern __u32                    cpu_caps_set[NCAPINTS + NBUGINTS];
 177
 178#ifdef CONFIG_SMP
 179DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
 180#define cpu_data(cpu)           per_cpu(cpu_info, cpu)
 181#else
 182#define cpu_info                boot_cpu_data
 183#define cpu_data(cpu)           boot_cpu_data
 184#endif
 185
 186extern const struct seq_operations cpuinfo_op;
 187
 188#define cache_line_size()       (boot_cpu_data.x86_cache_alignment)
 189
 190extern void cpu_detect(struct cpuinfo_x86 *c);
 191
 192static inline unsigned long long l1tf_pfn_limit(void)
 193{
 194        return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
 195}
 196
 197extern void early_cpu_init(void);
 198extern void identify_boot_cpu(void);
 199extern void identify_secondary_cpu(struct cpuinfo_x86 *);
 200extern void print_cpu_info(struct cpuinfo_x86 *);
 201void print_cpu_msr(struct cpuinfo_x86 *);
 202
 203#ifdef CONFIG_X86_32
 204extern int have_cpuid_p(void);
 205#else
 206static inline int have_cpuid_p(void)
 207{
 208        return 1;
 209}
 210#endif
 211static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
 212                                unsigned int *ecx, unsigned int *edx)
 213{
 214        /* ecx is often an input as well as an output. */
 215        asm volatile("cpuid"
 216            : "=a" (*eax),
 217              "=b" (*ebx),
 218              "=c" (*ecx),
 219              "=d" (*edx)
 220            : "0" (*eax), "2" (*ecx)
 221            : "memory");
 222}
 223
 224#define native_cpuid_reg(reg)                                   \
 225static inline unsigned int native_cpuid_##reg(unsigned int op)  \
 226{                                                               \
 227        unsigned int eax = op, ebx, ecx = 0, edx;               \
 228                                                                \
 229        native_cpuid(&eax, &ebx, &ecx, &edx);                   \
 230                                                                \
 231        return reg;                                             \
 232}
 233
 234/*
 235 * Native CPUID functions returning a single datum.
 236 */
 237native_cpuid_reg(eax)
 238native_cpuid_reg(ebx)
 239native_cpuid_reg(ecx)
 240native_cpuid_reg(edx)
 241
 242/*
 243 * Friendlier CR3 helpers.
 244 */
 245static inline unsigned long read_cr3_pa(void)
 246{
 247        return __read_cr3() & CR3_ADDR_MASK;
 248}
 249
 250static inline unsigned long native_read_cr3_pa(void)
 251{
 252        return __native_read_cr3() & CR3_ADDR_MASK;
 253}
 254
 255static inline void load_cr3(pgd_t *pgdir)
 256{
 257        write_cr3(__sme_pa(pgdir));
 258}
 259
 260/*
 261 * Note that while the legacy 'TSS' name comes from 'Task State Segment',
 262 * on modern x86 CPUs the TSS also holds information important to 64-bit mode,
 263 * unrelated to the task-switch mechanism:
 264 */
 265#ifdef CONFIG_X86_32
 266/* This is the TSS defined by the hardware. */
 267struct x86_hw_tss {
 268        unsigned short          back_link, __blh;
 269        unsigned long           sp0;
 270        unsigned short          ss0, __ss0h;
 271        unsigned long           sp1;
 272
 273        /*
 274         * We don't use ring 1, so ss1 is a convenient scratch space in
 275         * the same cacheline as sp0.  We use ss1 to cache the value in
 276         * MSR_IA32_SYSENTER_CS.  When we context switch
 277         * MSR_IA32_SYSENTER_CS, we first check if the new value being
 278         * written matches ss1, and, if it's not, then we wrmsr the new
 279         * value and update ss1.
 280         *
 281         * The only reason we context switch MSR_IA32_SYSENTER_CS is
 282         * that we set it to zero in vm86 tasks to avoid corrupting the
 283         * stack if we were to go through the sysenter path from vm86
 284         * mode.
 285         */
 286        unsigned short          ss1;    /* MSR_IA32_SYSENTER_CS */
 287
 288        unsigned short          __ss1h;
 289        unsigned long           sp2;
 290        unsigned short          ss2, __ss2h;
 291        unsigned long           __cr3;
 292        unsigned long           ip;
 293        unsigned long           flags;
 294        unsigned long           ax;
 295        unsigned long           cx;
 296        unsigned long           dx;
 297        unsigned long           bx;
 298        unsigned long           sp;
 299        unsigned long           bp;
 300        unsigned long           si;
 301        unsigned long           di;
 302        unsigned short          es, __esh;
 303        unsigned short          cs, __csh;
 304        unsigned short          ss, __ssh;
 305        unsigned short          ds, __dsh;
 306        unsigned short          fs, __fsh;
 307        unsigned short          gs, __gsh;
 308        unsigned short          ldt, __ldth;
 309        unsigned short          trace;
 310        unsigned short          io_bitmap_base;
 311
 312} __attribute__((packed));
 313#else
 314struct x86_hw_tss {
 315        u32                     reserved1;
 316        u64                     sp0;
 317
 318        /*
 319         * We store cpu_current_top_of_stack in sp1 so it's always accessible.
 320         * Linux does not use ring 1, so sp1 is not otherwise needed.
 321         */
 322        u64                     sp1;
 323
 324        /*
 325         * Since Linux does not use ring 2, the 'sp2' slot is unused by
 326         * hardware.  entry_SYSCALL_64 uses it as scratch space to stash
 327         * the user RSP value.
 328         */
 329        u64                     sp2;
 330
 331        u64                     reserved2;
 332        u64                     ist[7];
 333        u32                     reserved3;
 334        u32                     reserved4;
 335        u16                     reserved5;
 336        u16                     io_bitmap_base;
 337
 338} __attribute__((packed));
 339#endif
 340
 341/*
 342 * IO-bitmap sizes:
 343 */
 344#define IO_BITMAP_BITS                  65536
 345#define IO_BITMAP_BYTES                 (IO_BITMAP_BITS / BITS_PER_BYTE)
 346#define IO_BITMAP_LONGS                 (IO_BITMAP_BYTES / sizeof(long))
 347
 348#define IO_BITMAP_OFFSET_VALID_MAP                              \
 349        (offsetof(struct tss_struct, io_bitmap.bitmap) -        \
 350         offsetof(struct tss_struct, x86_tss))
 351
 352#define IO_BITMAP_OFFSET_VALID_ALL                              \
 353        (offsetof(struct tss_struct, io_bitmap.mapall) -        \
 354         offsetof(struct tss_struct, x86_tss))
 355
 356#ifdef CONFIG_X86_IOPL_IOPERM
 357/*
 358 * sizeof(unsigned long) coming from an extra "long" at the end of the
 359 * iobitmap. The limit is inclusive, i.e. the last valid byte.
 360 */
 361# define __KERNEL_TSS_LIMIT     \
 362        (IO_BITMAP_OFFSET_VALID_ALL + IO_BITMAP_BYTES + \
 363         sizeof(unsigned long) - 1)
 364#else
 365# define __KERNEL_TSS_LIMIT     \
 366        (offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1)
 367#endif
 368
 369/* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */
 370#define IO_BITMAP_OFFSET_INVALID        (__KERNEL_TSS_LIMIT + 1)
 371
 372struct entry_stack {
 373        char    stack[PAGE_SIZE];
 374};
 375
 376struct entry_stack_page {
 377        struct entry_stack stack;
 378} __aligned(PAGE_SIZE);
 379
 380/*
 381 * All IO bitmap related data stored in the TSS:
 382 */
 383struct x86_io_bitmap {
 384        /* The sequence number of the last active bitmap. */
 385        u64                     prev_sequence;
 386
 387        /*
 388         * Store the dirty size of the last io bitmap offender. The next
 389         * one will have to do the cleanup as the switch out to a non io
 390         * bitmap user will just set x86_tss.io_bitmap_base to a value
 391         * outside of the TSS limit. So for sane tasks there is no need to
 392         * actually touch the io_bitmap at all.
 393         */
 394        unsigned int            prev_max;
 395
 396        /*
 397         * The extra 1 is there because the CPU will access an
 398         * additional byte beyond the end of the IO permission
 399         * bitmap. The extra byte must be all 1 bits, and must
 400         * be within the limit.
 401         */
 402        unsigned long           bitmap[IO_BITMAP_LONGS + 1];
 403
 404        /*
 405         * Special I/O bitmap to emulate IOPL(3). All bytes zero,
 406         * except the additional byte at the end.
 407         */
 408        unsigned long           mapall[IO_BITMAP_LONGS + 1];
 409};
 410
 411struct tss_struct {
 412        /*
 413         * The fixed hardware portion.  This must not cross a page boundary
 414         * at risk of violating the SDM's advice and potentially triggering
 415         * errata.
 416         */
 417        struct x86_hw_tss       x86_tss;
 418
 419        struct x86_io_bitmap    io_bitmap;
 420} __aligned(PAGE_SIZE);
 421
 422DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw);
 423
 424/* Per CPU interrupt stacks */
 425struct irq_stack {
 426        char            stack[IRQ_STACK_SIZE];
 427} __aligned(IRQ_STACK_SIZE);
 428
 429#ifdef CONFIG_X86_32
 430DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
 431#else
 432/* The RO copy can't be accessed with this_cpu_xyz(), so use the RW copy. */
 433#define cpu_current_top_of_stack cpu_tss_rw.x86_tss.sp1
 434#endif
 435
 436#ifdef CONFIG_X86_64
 437struct fixed_percpu_data {
 438        /*
 439         * GCC hardcodes the stack canary as %gs:40.  Since the
 440         * irq_stack is the object at %gs:0, we reserve the bottom
 441         * 48 bytes of the irq stack for the canary.
 442         */
 443        char            gs_base[40];
 444        unsigned long   stack_canary;
 445};
 446
 447DECLARE_PER_CPU_FIRST(struct fixed_percpu_data, fixed_percpu_data) __visible;
 448DECLARE_INIT_PER_CPU(fixed_percpu_data);
 449
 450static inline unsigned long cpu_kernelmode_gs_base(int cpu)
 451{
 452        return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu);
 453}
 454
 455DECLARE_PER_CPU(void *, hardirq_stack_ptr);
 456DECLARE_PER_CPU(bool, hardirq_stack_inuse);
 457extern asmlinkage void ignore_sysret(void);
 458
 459/* Save actual FS/GS selectors and bases to current->thread */
 460void current_save_fsgs(void);
 461#else   /* X86_64 */
 462#ifdef CONFIG_STACKPROTECTOR
 463/*
 464 * Make sure stack canary segment base is cached-aligned:
 465 *   "For Intel Atom processors, avoid non zero segment base address
 466 *    that is not aligned to cache line boundary at all cost."
 467 * (Optim Ref Manual Assembly/Compiler Coding Rule 15.)
 468 */
 469struct stack_canary {
 470        char __pad[20];         /* canary at %gs:20 */
 471        unsigned long canary;
 472};
 473DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
 474#endif
 475DECLARE_PER_CPU(struct irq_stack *, hardirq_stack_ptr);
 476DECLARE_PER_CPU(struct irq_stack *, softirq_stack_ptr);
 477#endif  /* !X86_64 */
 478
 479extern unsigned int fpu_kernel_xstate_size;
 480extern unsigned int fpu_user_xstate_size;
 481
 482struct perf_event;
 483
 484struct thread_struct {
 485        /* Cached TLS descriptors: */
 486        struct desc_struct      tls_array[GDT_ENTRY_TLS_ENTRIES];
 487#ifdef CONFIG_X86_32
 488        unsigned long           sp0;
 489#endif
 490        unsigned long           sp;
 491#ifdef CONFIG_X86_32
 492        unsigned long           sysenter_cs;
 493#else
 494        unsigned short          es;
 495        unsigned short          ds;
 496        unsigned short          fsindex;
 497        unsigned short          gsindex;
 498#endif
 499
 500#ifdef CONFIG_X86_64
 501        unsigned long           fsbase;
 502        unsigned long           gsbase;
 503#else
 504        /*
 505         * XXX: this could presumably be unsigned short.  Alternatively,
 506         * 32-bit kernels could be taught to use fsindex instead.
 507         */
 508        unsigned long fs;
 509        unsigned long gs;
 510#endif
 511
 512        /* Save middle states of ptrace breakpoints */
 513        struct perf_event       *ptrace_bps[HBP_NUM];
 514        /* Debug status used for traps, single steps, etc... */
 515        unsigned long           virtual_dr6;
 516        /* Keep track of the exact dr7 value set by the user */
 517        unsigned long           ptrace_dr7;
 518        /* Fault info: */
 519        unsigned long           cr2;
 520        unsigned long           trap_nr;
 521        unsigned long           error_code;
 522#ifdef CONFIG_VM86
 523        /* Virtual 86 mode info */
 524        struct vm86             *vm86;
 525#endif
 526        /* IO permissions: */
 527        struct io_bitmap        *io_bitmap;
 528
 529        /*
 530         * IOPL. Priviledge level dependent I/O permission which is
 531         * emulated via the I/O bitmap to prevent user space from disabling
 532         * interrupts.
 533         */
 534        unsigned long           iopl_emul;
 535
 536        unsigned int            sig_on_uaccess_err:1;
 537
 538        /* Floating point and extended processor state */
 539        struct fpu              fpu;
 540        /*
 541         * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
 542         * the end.
 543         */
 544};
 545
 546/* Whitelist the FPU state from the task_struct for hardened usercopy. */
 547static inline void arch_thread_struct_whitelist(unsigned long *offset,
 548                                                unsigned long *size)
 549{
 550        *offset = offsetof(struct thread_struct, fpu.state);
 551        *size = fpu_kernel_xstate_size;
 552}
 553
 554static inline void
 555native_load_sp0(unsigned long sp0)
 556{
 557        this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
 558}
 559
 560static __always_inline void native_swapgs(void)
 561{
 562#ifdef CONFIG_X86_64
 563        asm volatile("swapgs" ::: "memory");
 564#endif
 565}
 566
 567static inline unsigned long current_top_of_stack(void)
 568{
 569        /*
 570         *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
 571         *  and around vm86 mode and sp0 on x86_64 is special because of the
 572         *  entry trampoline.
 573         */
 574        return this_cpu_read_stable(cpu_current_top_of_stack);
 575}
 576
 577static inline bool on_thread_stack(void)
 578{
 579        return (unsigned long)(current_top_of_stack() -
 580                               current_stack_pointer) < THREAD_SIZE;
 581}
 582
 583#ifdef CONFIG_PARAVIRT_XXL
 584#include <asm/paravirt.h>
 585#else
 586#define __cpuid                 native_cpuid
 587
 588static inline void load_sp0(unsigned long sp0)
 589{
 590        native_load_sp0(sp0);
 591}
 592
 593#endif /* CONFIG_PARAVIRT_XXL */
 594
 595/* Free all resources held by a thread. */
 596extern void release_thread(struct task_struct *);
 597
 598unsigned long get_wchan(struct task_struct *p);
 599
 600/*
 601 * Generic CPUID function
 602 * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
 603 * resulting in stale register contents being returned.
 604 */
 605static inline void cpuid(unsigned int op,
 606                         unsigned int *eax, unsigned int *ebx,
 607                         unsigned int *ecx, unsigned int *edx)
 608{
 609        *eax = op;
 610        *ecx = 0;
 611        __cpuid(eax, ebx, ecx, edx);
 612}
 613
 614/* Some CPUID calls want 'count' to be placed in ecx */
 615static inline void cpuid_count(unsigned int op, int count,
 616                               unsigned int *eax, unsigned int *ebx,
 617                               unsigned int *ecx, unsigned int *edx)
 618{
 619        *eax = op;
 620        *ecx = count;
 621        __cpuid(eax, ebx, ecx, edx);
 622}
 623
 624/*
 625 * CPUID functions returning a single datum
 626 */
 627static inline unsigned int cpuid_eax(unsigned int op)
 628{
 629        unsigned int eax, ebx, ecx, edx;
 630
 631        cpuid(op, &eax, &ebx, &ecx, &edx);
 632
 633        return eax;
 634}
 635
 636static inline unsigned int cpuid_ebx(unsigned int op)
 637{
 638        unsigned int eax, ebx, ecx, edx;
 639
 640        cpuid(op, &eax, &ebx, &ecx, &edx);
 641
 642        return ebx;
 643}
 644
 645static inline unsigned int cpuid_ecx(unsigned int op)
 646{
 647        unsigned int eax, ebx, ecx, edx;
 648
 649        cpuid(op, &eax, &ebx, &ecx, &edx);
 650
 651        return ecx;
 652}
 653
 654static inline unsigned int cpuid_edx(unsigned int op)
 655{
 656        unsigned int eax, ebx, ecx, edx;
 657
 658        cpuid(op, &eax, &ebx, &ecx, &edx);
 659
 660        return edx;
 661}
 662
 663extern void select_idle_routine(const struct cpuinfo_x86 *c);
 664extern void amd_e400_c1e_apic_setup(void);
 665
 666extern unsigned long            boot_option_idle_override;
 667
 668enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
 669                         IDLE_POLL};
 670
 671extern void enable_sep_cpu(void);
 672extern int sysenter_setup(void);
 673
 674
 675/* Defined in head.S */
 676extern struct desc_ptr          early_gdt_descr;
 677
 678extern void switch_to_new_gdt(int);
 679extern void load_direct_gdt(int);
 680extern void load_fixmap_gdt(int);
 681extern void load_percpu_segment(int);
 682extern void cpu_init(void);
 683extern void cpu_init_exception_handling(void);
 684extern void cr4_init(void);
 685
 686static inline unsigned long get_debugctlmsr(void)
 687{
 688        unsigned long debugctlmsr = 0;
 689
 690#ifndef CONFIG_X86_DEBUGCTLMSR
 691        if (boot_cpu_data.x86 < 6)
 692                return 0;
 693#endif
 694        rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
 695
 696        return debugctlmsr;
 697}
 698
 699static inline void update_debugctlmsr(unsigned long debugctlmsr)
 700{
 701#ifndef CONFIG_X86_DEBUGCTLMSR
 702        if (boot_cpu_data.x86 < 6)
 703                return;
 704#endif
 705        wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
 706}
 707
 708extern void set_task_blockstep(struct task_struct *task, bool on);
 709
 710/* Boot loader type from the setup header: */
 711extern int                      bootloader_type;
 712extern int                      bootloader_version;
 713
 714extern char                     ignore_fpu_irq;
 715
 716#define HAVE_ARCH_PICK_MMAP_LAYOUT 1
 717#define ARCH_HAS_PREFETCHW
 718#define ARCH_HAS_SPINLOCK_PREFETCH
 719
 720#ifdef CONFIG_X86_32
 721# define BASE_PREFETCH          ""
 722# define ARCH_HAS_PREFETCH
 723#else
 724# define BASE_PREFETCH          "prefetcht0 %P1"
 725#endif
 726
 727/*
 728 * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
 729 *
 730 * It's not worth to care about 3dnow prefetches for the K6
 731 * because they are microcoded there and very slow.
 732 */
 733static inline void prefetch(const void *x)
 734{
 735        alternative_input(BASE_PREFETCH, "prefetchnta %P1",
 736                          X86_FEATURE_XMM,
 737                          "m" (*(const char *)x));
 738}
 739
 740/*
 741 * 3dnow prefetch to get an exclusive cache line.
 742 * Useful for spinlocks to avoid one state transition in the
 743 * cache coherency protocol:
 744 */
 745static __always_inline void prefetchw(const void *x)
 746{
 747        alternative_input(BASE_PREFETCH, "prefetchw %P1",
 748                          X86_FEATURE_3DNOWPREFETCH,
 749                          "m" (*(const char *)x));
 750}
 751
 752static inline void spin_lock_prefetch(const void *x)
 753{
 754        prefetchw(x);
 755}
 756
 757#define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
 758                           TOP_OF_KERNEL_STACK_PADDING)
 759
 760#define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
 761
 762#define task_pt_regs(task) \
 763({                                                                      \
 764        unsigned long __ptr = (unsigned long)task_stack_page(task);     \
 765        __ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;             \
 766        ((struct pt_regs *)__ptr) - 1;                                  \
 767})
 768
 769#ifdef CONFIG_X86_32
 770#define INIT_THREAD  {                                                    \
 771        .sp0                    = TOP_OF_INIT_STACK,                      \
 772        .sysenter_cs            = __KERNEL_CS,                            \
 773}
 774
 775#define KSTK_ESP(task)          (task_pt_regs(task)->sp)
 776
 777#else
 778#define INIT_THREAD { }
 779
 780extern unsigned long KSTK_ESP(struct task_struct *task);
 781
 782#endif /* CONFIG_X86_64 */
 783
 784extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
 785                                               unsigned long new_sp);
 786
 787/*
 788 * This decides where the kernel will search for a free chunk of vm
 789 * space during mmap's.
 790 */
 791#define __TASK_UNMAPPED_BASE(task_size) (PAGE_ALIGN(task_size / 3))
 792#define TASK_UNMAPPED_BASE              __TASK_UNMAPPED_BASE(TASK_SIZE_LOW)
 793
 794#define KSTK_EIP(task)          (task_pt_regs(task)->ip)
 795
 796/* Get/set a process' ability to use the timestamp counter instruction */
 797#define GET_TSC_CTL(adr)        get_tsc_mode((adr))
 798#define SET_TSC_CTL(val)        set_tsc_mode((val))
 799
 800extern int get_tsc_mode(unsigned long adr);
 801extern int set_tsc_mode(unsigned int val);
 802
 803DECLARE_PER_CPU(u64, msr_misc_features_shadow);
 804
 805#ifdef CONFIG_CPU_SUP_AMD
 806extern u32 amd_get_nodes_per_socket(void);
 807#else
 808static inline u32 amd_get_nodes_per_socket(void)        { return 0; }
 809#endif
 810
 811static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
 812{
 813        uint32_t base, eax, signature[3];
 814
 815        for (base = 0x40000000; base < 0x40010000; base += 0x100) {
 816                cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
 817
 818                if (!memcmp(sig, signature, 12) &&
 819                    (leaves == 0 || ((eax - base) >= leaves)))
 820                        return base;
 821        }
 822
 823        return 0;
 824}
 825
 826extern unsigned long arch_align_stack(unsigned long sp);
 827void free_init_pages(const char *what, unsigned long begin, unsigned long end);
 828extern void free_kernel_image_pages(const char *what, void *begin, void *end);
 829
 830void default_idle(void);
 831#ifdef  CONFIG_XEN
 832bool xen_set_default_idle(void);
 833#else
 834#define xen_set_default_idle 0
 835#endif
 836
 837void stop_this_cpu(void *dummy);
 838void microcode_check(void);
 839
 840enum l1tf_mitigations {
 841        L1TF_MITIGATION_OFF,
 842        L1TF_MITIGATION_FLUSH_NOWARN,
 843        L1TF_MITIGATION_FLUSH,
 844        L1TF_MITIGATION_FLUSH_NOSMT,
 845        L1TF_MITIGATION_FULL,
 846        L1TF_MITIGATION_FULL_FORCE
 847};
 848
 849extern enum l1tf_mitigations l1tf_mitigation;
 850
 851enum mds_mitigations {
 852        MDS_MITIGATION_OFF,
 853        MDS_MITIGATION_FULL,
 854        MDS_MITIGATION_VMWERV,
 855};
 856
 857#endif /* _ASM_X86_PROCESSOR_H */
 858