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