arch/x86/include/asm/processor.h

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
current_text_addr
have_cpuid_p
native_cpuid
load_cr3
DECLARE_PER_CPU_FIRST
native_set_iopl_mask
native_load_sp0
native_swapgs
load_sp0
set_in_cr4
clear_in_cr4
cpuid
cpuid_count
cpuid_eax
cpuid_ebx
cpuid_ecx
cpuid_edx
rep_nop
cpu_relax
sync_core
get_debugctlmsr
update_debugctlmsr
prefetch
prefetchw
spin_lock_prefetch
hypervisor_cpuid_base
#ifndef _ASM_X86_PROCESSOR_H
#define _ASM_X86_PROCESSOR_H

#include <asm/processor-flags.h>

/* Forward declaration, a strange C thing */
struct task_struct;
struct mm_struct;

#include <asm/vm86.h>
#include <asm/math_emu.h>
#include <asm/segment.h>
#include <asm/types.h>
#include <asm/sigcontext.h>
#include <asm/current.h>
#include <asm/cpufeature.h>
#include <asm/page.h>
#include <asm/pgtable_types.h>
#include <asm/percpu.h>
#include <asm/msr.h>
#include <asm/desc_defs.h>
#include <asm/nops.h>
#include <asm/special_insns.h>

#include <linux/personality.h>
#include <linux/cpumask.h>
#include <linux/cache.h>
#include <linux/threads.h>
#include <linux/math64.h>
#include <linux/err.h>
#include <linux/irqflags.h>

/*
 * We handle most unaligned accesses in hardware.  On the other hand
 * unaligned DMA can be quite expensive on some Nehalem processors.
 *
 * Based on this we disable the IP header alignment in network drivers.
 */
#define NET_IP_ALIGN    0

#define HBP_NUM 4
/*
 * Default implementation of macro that returns current
 * instruction pointer ("program counter").
 */
static inline void *current_text_addr(void)
{
        void *pc;

        asm volatile("mov $1f, %0; 1:":"=r" (pc));

        return pc;
}

#ifdef CONFIG_X86_VSMP
# define ARCH_MIN_TASKALIGN             (1 << INTERNODE_CACHE_SHIFT)
# define ARCH_MIN_MMSTRUCT_ALIGN        (1 << INTERNODE_CACHE_SHIFT)
#else
# define ARCH_MIN_TASKALIGN             16
# define ARCH_MIN_MMSTRUCT_ALIGN        0
#endif

enum tlb_infos {
        ENTRIES,
        NR_INFO
};

extern u16 __read_mostly tlb_lli_4k[NR_INFO];
extern u16 __read_mostly tlb_lli_2m[NR_INFO];
extern u16 __read_mostly tlb_lli_4m[NR_INFO];
extern u16 __read_mostly tlb_lld_4k[NR_INFO];
extern u16 __read_mostly tlb_lld_2m[NR_INFO];
extern u16 __read_mostly tlb_lld_4m[NR_INFO];
extern u16 __read_mostly tlb_lld_1g[NR_INFO];

/*
 *  CPU type and hardware bug flags. Kept separately for each CPU.
 *  Members of this structure are referenced in head.S, so think twice
 *  before touching them. [mj]
 */

struct cpuinfo_x86 {
        __u8                    x86;            /* CPU family */
        __u8                    x86_vendor;     /* CPU vendor */
        __u8                    x86_model;
        __u8                    x86_mask;
#ifdef CONFIG_X86_32
        char                    wp_works_ok;    /* It doesn't on 386's */

        /* Problems on some 486Dx4's and old 386's: */
        char                    rfu;
        char                    pad0;
        char                    pad1;
#else
        /* Number of 4K pages in DTLB/ITLB combined(in pages): */
        int                     x86_tlbsize;
#endif
        __u8                    x86_virt_bits;
        __u8                    x86_phys_bits;
        /* CPUID returned core id bits: */
        __u8                    x86_coreid_bits;
        /* Max extended CPUID function supported: */
        __u32                   extended_cpuid_level;
        /* Maximum supported CPUID level, -1=no CPUID: */
        int                     cpuid_level;
        __u32                   x86_capability[NCAPINTS + NBUGINTS];
        char                    x86_vendor_id[16];
        char                    x86_model_id[64];
        /* in KB - valid for CPUS which support this call: */
        int                     x86_cache_size;
        int                     x86_cache_alignment;    /* In bytes */
        int                     x86_power;
        unsigned long           loops_per_jiffy;
        /* cpuid returned max cores value: */
        u16                      x86_max_cores;
        u16                     apicid;
        u16                     initial_apicid;
        u16                     x86_clflush_size;
        /* number of cores as seen by the OS: */
        u16                     booted_cores;
        /* Physical processor id: */
        u16                     phys_proc_id;
        /* Core id: */
        u16                     cpu_core_id;
        /* Compute unit id */
        u8                      compute_unit_id;
        /* Index into per_cpu list: */
        u16                     cpu_index;
        u32                     microcode;
} __attribute__((__aligned__(SMP_CACHE_BYTES)));

#define X86_VENDOR_INTEL        0
#define X86_VENDOR_CYRIX        1
#define X86_VENDOR_AMD          2
#define X86_VENDOR_UMC          3
#define X86_VENDOR_CENTAUR      5
#define X86_VENDOR_TRANSMETA    7
#define X86_VENDOR_NSC          8
#define X86_VENDOR_NUM          9

#define X86_VENDOR_UNKNOWN      0xff

/*
 * capabilities of CPUs
 */
extern struct cpuinfo_x86       boot_cpu_data;
extern struct cpuinfo_x86       new_cpu_data;

extern struct tss_struct        doublefault_tss;
extern __u32                    cpu_caps_cleared[NCAPINTS];
extern __u32                    cpu_caps_set[NCAPINTS];

#ifdef CONFIG_SMP
DECLARE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
#define cpu_data(cpu)           per_cpu(cpu_info, cpu)
#else
#define cpu_info                boot_cpu_data
#define cpu_data(cpu)           boot_cpu_data
#endif

extern const struct seq_operations cpuinfo_op;

#define cache_line_size()       (boot_cpu_data.x86_cache_alignment)

extern void cpu_detect(struct cpuinfo_x86 *c);
extern void fpu_detect(struct cpuinfo_x86 *c);

extern void early_cpu_init(void);
extern void identify_boot_cpu(void);
extern void identify_secondary_cpu(struct cpuinfo_x86 *);
extern void print_cpu_info(struct cpuinfo_x86 *);
void print_cpu_msr(struct cpuinfo_x86 *);
extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
extern void init_amd_cacheinfo(struct cpuinfo_x86 *c);

extern void detect_extended_topology(struct cpuinfo_x86 *c);
extern void detect_ht(struct cpuinfo_x86 *c);

#ifdef CONFIG_X86_32
extern int have_cpuid_p(void);
#else
static inline int have_cpuid_p(void)
{
        return 1;
}
#endif
static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
                                unsigned int *ecx, unsigned int *edx)
{
        /* ecx is often an input as well as an output. */
        asm volatile("cpuid"
            : "=a" (*eax),
              "=b" (*ebx),
              "=c" (*ecx),
              "=d" (*edx)
            : "0" (*eax), "2" (*ecx)
            : "memory");
}

static inline void load_cr3(pgd_t *pgdir)
{
        write_cr3(__pa(pgdir));
}

#ifdef CONFIG_X86_32
/* This is the TSS defined by the hardware. */
struct x86_hw_tss {
        unsigned short          back_link, __blh;
        unsigned long           sp0;
        unsigned short          ss0, __ss0h;
        unsigned long           sp1;
        /* ss1 caches MSR_IA32_SYSENTER_CS: */
        unsigned short          ss1, __ss1h;
        unsigned long           sp2;
        unsigned short          ss2, __ss2h;
        unsigned long           __cr3;
        unsigned long           ip;
        unsigned long           flags;
        unsigned long           ax;
        unsigned long           cx;
        unsigned long           dx;
        unsigned long           bx;
        unsigned long           sp;
        unsigned long           bp;
        unsigned long           si;
        unsigned long           di;
        unsigned short          es, __esh;
        unsigned short          cs, __csh;
        unsigned short          ss, __ssh;
        unsigned short          ds, __dsh;
        unsigned short          fs, __fsh;
        unsigned short          gs, __gsh;
        unsigned short          ldt, __ldth;
        unsigned short          trace;
        unsigned short          io_bitmap_base;

} __attribute__((packed));
#else
struct x86_hw_tss {
        u32                     reserved1;
        u64                     sp0;
        u64                     sp1;
        u64                     sp2;
        u64                     reserved2;
        u64                     ist[7];
        u32                     reserved3;
        u32                     reserved4;
        u16                     reserved5;
        u16                     io_bitmap_base;

} __attribute__((packed)) ____cacheline_aligned;
#endif

/*
 * IO-bitmap sizes:
 */
#define IO_BITMAP_BITS                  65536
#define IO_BITMAP_BYTES                 (IO_BITMAP_BITS/8)
#define IO_BITMAP_LONGS                 (IO_BITMAP_BYTES/sizeof(long))
#define IO_BITMAP_OFFSET                offsetof(struct tss_struct, io_bitmap)
#define INVALID_IO_BITMAP_OFFSET        0x8000

struct tss_struct {
        /*
         * The hardware state:
         */
        struct x86_hw_tss       x86_tss;

        /*
         * The extra 1 is there because the CPU will access an
         * additional byte beyond the end of the IO permission
         * bitmap. The extra byte must be all 1 bits, and must
         * be within the limit.
         */
        unsigned long           io_bitmap[IO_BITMAP_LONGS + 1];

        /*
         * .. and then another 0x100 bytes for the emergency kernel stack:
         */
        unsigned long           stack[64];

} ____cacheline_aligned;

DECLARE_PER_CPU_SHARED_ALIGNED(struct tss_struct, init_tss);

/*
 * Save the original ist values for checking stack pointers during debugging
 */
struct orig_ist {
        unsigned long           ist[7];
};

#define MXCSR_DEFAULT           0x1f80

struct i387_fsave_struct {
        u32                     cwd;    /* FPU Control Word             */
        u32                     swd;    /* FPU Status Word              */
        u32                     twd;    /* FPU Tag Word                 */
        u32                     fip;    /* FPU IP Offset                */
        u32                     fcs;    /* FPU IP Selector              */
        u32                     foo;    /* FPU Operand Pointer Offset   */
        u32                     fos;    /* FPU Operand Pointer Selector */

        /* 8*10 bytes for each FP-reg = 80 bytes:                       */
        u32                     st_space[20];

        /* Software status information [not touched by FSAVE ]:         */
        u32                     status;
};

struct i387_fxsave_struct {
        u16                     cwd; /* Control Word                    */
        u16                     swd; /* Status Word                     */
        u16                     twd; /* Tag Word                        */
        u16                     fop; /* Last Instruction Opcode         */
        union {
                struct {
                        u64     rip; /* Instruction Pointer             */
                        u64     rdp; /* Data Pointer                    */
                };
                struct {
                        u32     fip; /* FPU IP Offset                   */
                        u32     fcs; /* FPU IP Selector                 */
                        u32     foo; /* FPU Operand Offset              */
                        u32     fos; /* FPU Operand Selector            */
                };
        };
        u32                     mxcsr;          /* MXCSR Register State */
        u32                     mxcsr_mask;     /* MXCSR Mask           */

        /* 8*16 bytes for each FP-reg = 128 bytes:                      */
        u32                     st_space[32];

        /* 16*16 bytes for each XMM-reg = 256 bytes:                    */
        u32                     xmm_space[64];

        u32                     padding[12];

        union {
                u32             padding1[12];
                u32             sw_reserved[12];
        };

} __attribute__((aligned(16)));

struct i387_soft_struct {
        u32                     cwd;
        u32                     swd;
        u32                     twd;
        u32                     fip;
        u32                     fcs;
        u32                     foo;
        u32                     fos;
        /* 8*10 bytes for each FP-reg = 80 bytes: */
        u32                     st_space[20];
        u8                      ftop;
        u8                      changed;
        u8                      lookahead;
        u8                      no_update;
        u8                      rm;
        u8                      alimit;
        struct math_emu_info    *info;
        u32                     entry_eip;
};

struct ymmh_struct {
        /* 16 * 16 bytes for each YMMH-reg = 256 bytes */
        u32 ymmh_space[64];
};

/* We don't support LWP yet: */
struct lwp_struct {
        u8 reserved[128];
};

struct bndregs_struct {
        u64 bndregs[8];
} __packed;

struct bndcsr_struct {
        u64 cfg_reg_u;
        u64 status_reg;
} __packed;

struct xsave_hdr_struct {
        u64 xstate_bv;
        u64 xcomp_bv;
        u64 reserved[6];
} __attribute__((packed));

struct xsave_struct {
        struct i387_fxsave_struct i387;
        struct xsave_hdr_struct xsave_hdr;
        struct ymmh_struct ymmh;
        struct lwp_struct lwp;
        struct bndregs_struct bndregs;
        struct bndcsr_struct bndcsr;
        /* new processor state extensions will go here */
} __attribute__ ((packed, aligned (64)));

union thread_xstate {
        struct i387_fsave_struct        fsave;
        struct i387_fxsave_struct       fxsave;
        struct i387_soft_struct         soft;
        struct xsave_struct             xsave;
};

struct fpu {
        unsigned int last_cpu;
        unsigned int has_fpu;
        union thread_xstate *state;
};

#ifdef CONFIG_X86_64
DECLARE_PER_CPU(struct orig_ist, orig_ist);

union irq_stack_union {
        char irq_stack[IRQ_STACK_SIZE];
        /*
         * GCC hardcodes the stack canary as %gs:40.  Since the
         * irq_stack is the object at %gs:0, we reserve the bottom
         * 48 bytes of the irq stack for the canary.
         */
        struct {
                char gs_base[40];
                unsigned long stack_canary;
        };
};

DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __visible;
DECLARE_INIT_PER_CPU(irq_stack_union);

DECLARE_PER_CPU(char *, irq_stack_ptr);
DECLARE_PER_CPU(unsigned int, irq_count);
extern asmlinkage void ignore_sysret(void);
#else   /* X86_64 */
#ifdef CONFIG_CC_STACKPROTECTOR
/*
 * Make sure stack canary segment base is cached-aligned:
 *   "For Intel Atom processors, avoid non zero segment base address
 *    that is not aligned to cache line boundary at all cost."
 * (Optim Ref Manual Assembly/Compiler Coding Rule 15.)
 */
struct stack_canary {
        char __pad[20];         /* canary at %gs:20 */
        unsigned long canary;
};
DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
#endif
/*
 * per-CPU IRQ handling stacks
 */
struct irq_stack {
        u32                     stack[THREAD_SIZE/sizeof(u32)];
} __aligned(THREAD_SIZE);

DECLARE_PER_CPU(struct irq_stack *, hardirq_stack);
DECLARE_PER_CPU(struct irq_stack *, softirq_stack);
#endif  /* X86_64 */

extern unsigned int xstate_size;
extern void free_thread_xstate(struct task_struct *);
extern struct kmem_cache *task_xstate_cachep;

struct perf_event;

struct thread_struct {
        /* Cached TLS descriptors: */
        struct desc_struct      tls_array[GDT_ENTRY_TLS_ENTRIES];
        unsigned long           sp0;
        unsigned long           sp;
#ifdef CONFIG_X86_32
        unsigned long           sysenter_cs;
#else
        unsigned long           usersp; /* Copy from PDA */
        unsigned short          es;
        unsigned short          ds;
        unsigned short          fsindex;
        unsigned short          gsindex;
#endif
#ifdef CONFIG_X86_32
        unsigned long           ip;
#endif
#ifdef CONFIG_X86_64
        unsigned long           fs;
#endif
        unsigned long           gs;
        /* Save middle states of ptrace breakpoints */
        struct perf_event       *ptrace_bps[HBP_NUM];
        /* Debug status used for traps, single steps, etc... */
        unsigned long           debugreg6;
        /* Keep track of the exact dr7 value set by the user */
        unsigned long           ptrace_dr7;
        /* Fault info: */
        unsigned long           cr2;
        unsigned long           trap_nr;
        unsigned long           error_code;
        /* floating point and extended processor state */
        struct fpu              fpu;
#ifdef CONFIG_X86_32
        /* Virtual 86 mode info */
        struct vm86_struct __user *vm86_info;
        unsigned long           screen_bitmap;
        unsigned long           v86flags;
        unsigned long           v86mask;
        unsigned long           saved_sp0;
        unsigned int            saved_fs;
        unsigned int            saved_gs;
#endif
        /* IO permissions: */
        unsigned long           *io_bitmap_ptr;
        unsigned long           iopl;
        /* Max allowed port in the bitmap, in bytes: */
        unsigned                io_bitmap_max;
        /*
         * fpu_counter contains the number of consecutive context switches
         * that the FPU is used. If this is over a threshold, the lazy fpu
         * saving becomes unlazy to save the trap. This is an unsigned char
         * so that after 256 times the counter wraps and the behavior turns
         * lazy again; this to deal with bursty apps that only use FPU for
         * a short time
         */
        unsigned char fpu_counter;
};

/*
 * Set IOPL bits in EFLAGS from given mask
 */
static inline void native_set_iopl_mask(unsigned mask)
{
#ifdef CONFIG_X86_32
        unsigned int reg;

        asm volatile ("pushfl;"
                      "popl %0;"
                      "andl %1, %0;"
                      "orl %2, %0;"
                      "pushl %0;"
                      "popfl"
                      : "=&r" (reg)
                      : "i" (~X86_EFLAGS_IOPL), "r" (mask));
#endif
}

static inline void
native_load_sp0(struct tss_struct *tss, struct thread_struct *thread)
{
        tss->x86_tss.sp0 = thread->sp0;
#ifdef CONFIG_X86_32
        /* Only happens when SEP is enabled, no need to test "SEP"arately: */
        if (unlikely(tss->x86_tss.ss1 != thread->sysenter_cs)) {
                tss->x86_tss.ss1 = thread->sysenter_cs;
                wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
        }
#endif
}

static inline void native_swapgs(void)
{
#ifdef CONFIG_X86_64
        asm volatile("swapgs" ::: "memory");
#endif
}

#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#define __cpuid                 native_cpuid
#define paravirt_enabled()      0

static inline void load_sp0(struct tss_struct *tss,
                            struct thread_struct *thread)
{
        native_load_sp0(tss, thread);
}

#define set_iopl_mask native_set_iopl_mask
#endif /* CONFIG_PARAVIRT */

/*
 * Save the cr4 feature set we're using (ie
 * Pentium 4MB enable and PPro Global page
 * enable), so that any CPU's that boot up
 * after us can get the correct flags.
 */
extern unsigned long mmu_cr4_features;
extern u32 *trampoline_cr4_features;

static inline void set_in_cr4(unsigned long mask)
{
        unsigned long cr4;

        mmu_cr4_features |= mask;
        if (trampoline_cr4_features)
                *trampoline_cr4_features = mmu_cr4_features;
        cr4 = read_cr4();
        cr4 |= mask;
        write_cr4(cr4);
}

static inline void clear_in_cr4(unsigned long mask)
{
        unsigned long cr4;

        mmu_cr4_features &= ~mask;
        if (trampoline_cr4_features)
                *trampoline_cr4_features = mmu_cr4_features;
        cr4 = read_cr4();
        cr4 &= ~mask;
        write_cr4(cr4);
}

typedef struct {
        unsigned long           seg;
} mm_segment_t;


/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);

unsigned long get_wchan(struct task_struct *p);

/*
 * Generic CPUID function
 * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
 * resulting in stale register contents being returned.
 */
static inline void cpuid(unsigned int op,
                         unsigned int *eax, unsigned int *ebx,
                         unsigned int *ecx, unsigned int *edx)
{
        *eax = op;
        *ecx = 0;
        __cpuid(eax, ebx, ecx, edx);
}

/* Some CPUID calls want 'count' to be placed in ecx */
static inline void cpuid_count(unsigned int op, int count,
                               unsigned int *eax, unsigned int *ebx,
                               unsigned int *ecx, unsigned int *edx)
{
        *eax = op;
        *ecx = count;
        __cpuid(eax, ebx, ecx, edx);
}

/*
 * CPUID functions returning a single datum
 */
static inline unsigned int cpuid_eax(unsigned int op)
{
        unsigned int eax, ebx, ecx, edx;

        cpuid(op, &eax, &ebx, &ecx, &edx);

        return eax;
}

static inline unsigned int cpuid_ebx(unsigned int op)
{
        unsigned int eax, ebx, ecx, edx;

        cpuid(op, &eax, &ebx, &ecx, &edx);

        return ebx;
}

static inline unsigned int cpuid_ecx(unsigned int op)
{
        unsigned int eax, ebx, ecx, edx;

        cpuid(op, &eax, &ebx, &ecx, &edx);

        return ecx;
}

static inline unsigned int cpuid_edx(unsigned int op)
{
        unsigned int eax, ebx, ecx, edx;

        cpuid(op, &eax, &ebx, &ecx, &edx);

        return edx;
}

/* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
static inline void rep_nop(void)
{
        asm volatile("rep; nop" ::: "memory");
}

static inline void cpu_relax(void)
{
        rep_nop();
}

#define cpu_relax_lowlatency() cpu_relax()

/* Stop speculative execution and prefetching of modified code. */
static inline void sync_core(void)
{
        int tmp;

#ifdef CONFIG_M486
        /*
         * Do a CPUID if available, otherwise do a jump.  The jump
         * can conveniently enough be the jump around CPUID.
         */
        asm volatile("cmpl %2,%1\n\t"
                     "jl 1f\n\t"
                     "cpuid\n"
                     "1:"
                     : "=a" (tmp)
                     : "rm" (boot_cpu_data.cpuid_level), "ri" (0), "0" (1)
                     : "ebx", "ecx", "edx", "memory");
#else
        /*
         * CPUID is a barrier to speculative execution.
         * Prefetched instructions are automatically
         * invalidated when modified.
         */
        asm volatile("cpuid"
                     : "=a" (tmp)
                     : "0" (1)
                     : "ebx", "ecx", "edx", "memory");
#endif
}

extern void select_idle_routine(const struct cpuinfo_x86 *c);
extern void init_amd_e400_c1e_mask(void);

extern unsigned long            boot_option_idle_override;
extern bool                     amd_e400_c1e_detected;

enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
                         IDLE_POLL};

extern void enable_sep_cpu(void);
extern int sysenter_setup(void);

extern void early_trap_init(void);
void early_trap_pf_init(void);

/* Defined in head.S */
extern struct desc_ptr          early_gdt_descr;

extern void cpu_set_gdt(int);
extern void switch_to_new_gdt(int);
extern void load_percpu_segment(int);
extern void cpu_init(void);

static inline unsigned long get_debugctlmsr(void)
{
        unsigned long debugctlmsr = 0;

#ifndef CONFIG_X86_DEBUGCTLMSR
        if (boot_cpu_data.x86 < 6)
                return 0;
#endif
        rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);

        return debugctlmsr;
}

static inline void update_debugctlmsr(unsigned long debugctlmsr)
{
#ifndef CONFIG_X86_DEBUGCTLMSR
        if (boot_cpu_data.x86 < 6)
                return;
#endif
        wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
}

extern void set_task_blockstep(struct task_struct *task, bool on);

/*
 * from system description table in BIOS. Mostly for MCA use, but
 * others may find it useful:
 */
extern unsigned int             machine_id;
extern unsigned int             machine_submodel_id;
extern unsigned int             BIOS_revision;

/* Boot loader type from the setup header: */
extern int                      bootloader_type;
extern int                      bootloader_version;

extern char                     ignore_fpu_irq;

#define HAVE_ARCH_PICK_MMAP_LAYOUT 1
#define ARCH_HAS_PREFETCHW
#define ARCH_HAS_SPINLOCK_PREFETCH

#ifdef CONFIG_X86_32
# define BASE_PREFETCH          ASM_NOP4
# define ARCH_HAS_PREFETCH
#else
# define BASE_PREFETCH          "prefetcht0 (%1)"
#endif

/*
 * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
 *
 * It's not worth to care about 3dnow prefetches for the K6
 * because they are microcoded there and very slow.
 */
static inline void prefetch(const void *x)
{
        alternative_input(BASE_PREFETCH,
                          "prefetchnta (%1)",
                          X86_FEATURE_XMM,
                          "r" (x));
}

/*
 * 3dnow prefetch to get an exclusive cache line.
 * Useful for spinlocks to avoid one state transition in the
 * cache coherency protocol:
 */
static inline void prefetchw(const void *x)
{
        alternative_input(BASE_PREFETCH,
                          "prefetchw (%1)",
                          X86_FEATURE_3DNOW,
                          "r" (x));
}

static inline void spin_lock_prefetch(const void *x)
{
        prefetchw(x);
}

#ifdef CONFIG_X86_32
/*
 * User space process size: 3GB (default).
 */
#define TASK_SIZE               PAGE_OFFSET
#define TASK_SIZE_MAX           TASK_SIZE
#define STACK_TOP               TASK_SIZE
#define STACK_TOP_MAX           STACK_TOP

#define INIT_THREAD  {                                                    \
        .sp0                    = sizeof(init_stack) + (long)&init_stack, \
        .vm86_info              = NULL,                                   \
        .sysenter_cs            = __KERNEL_CS,                            \
        .io_bitmap_ptr          = NULL,                                   \
}

/*
 * Note that the .io_bitmap member must be extra-big. This is because
 * the CPU will access an additional byte beyond the end of the IO
 * permission bitmap. The extra byte must be all 1 bits, and must
 * be within the limit.
 */
#define INIT_TSS  {                                                       \
        .x86_tss = {                                                      \
                .sp0            = sizeof(init_stack) + (long)&init_stack, \
                .ss0            = __KERNEL_DS,                            \
                .ss1            = __KERNEL_CS,                            \
                .io_bitmap_base = INVALID_IO_BITMAP_OFFSET,               \
         },                                                               \
        .io_bitmap              = { [0 ... IO_BITMAP_LONGS] = ~0 },       \
}

extern unsigned long thread_saved_pc(struct task_struct *tsk);

#define THREAD_SIZE_LONGS      (THREAD_SIZE/sizeof(unsigned long))
#define KSTK_TOP(info)                                                 \
({                                                                     \
       unsigned long *__ptr = (unsigned long *)(info);                 \
       (unsigned long)(&__ptr[THREAD_SIZE_LONGS]);                     \
})

/*
 * The below -8 is to reserve 8 bytes on top of the ring0 stack.
 * This is necessary to guarantee that the entire "struct pt_regs"
 * is accessible even if the CPU haven't stored the SS/ESP registers
 * on the stack (interrupt gate does not save these registers
 * when switching to the same priv ring).
 * Therefore beware: accessing the ss/esp fields of the
 * "struct pt_regs" is possible, but they may contain the
 * completely wrong values.
 */
#define task_pt_regs(task)                                             \
({                                                                     \
       struct pt_regs *__regs__;                                       \
       __regs__ = (struct pt_regs *)(KSTK_TOP(task_stack_page(task))-8); \
       __regs__ - 1;                                                   \
})

#define KSTK_ESP(task)          (task_pt_regs(task)->sp)

#else
/*
 * User space process size. 47bits minus one guard page.
 */
#define TASK_SIZE_MAX   ((1UL << 47) - PAGE_SIZE)

/* This decides where the kernel will search for a free chunk of vm
 * space during mmap's.
 */
#define IA32_PAGE_OFFSET        ((current->personality & ADDR_LIMIT_3GB) ? \
                                        0xc0000000 : 0xFFFFe000)

#define TASK_SIZE               (test_thread_flag(TIF_ADDR32) ? \
                                        IA32_PAGE_OFFSET : TASK_SIZE_MAX)
#define TASK_SIZE_OF(child)     ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
                                        IA32_PAGE_OFFSET : TASK_SIZE_MAX)

#define STACK_TOP               TASK_SIZE
#define STACK_TOP_MAX           TASK_SIZE_MAX

#define INIT_THREAD  { \
        .sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
}

#define INIT_TSS  { \
        .x86_tss.sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
}

/*
 * Return saved PC of a blocked thread.
 * What is this good for? it will be always the scheduler or ret_from_fork.
 */
#define thread_saved_pc(t)      (*(unsigned long *)((t)->thread.sp - 8))

#define task_pt_regs(tsk)       ((struct pt_regs *)(tsk)->thread.sp0 - 1)
extern unsigned long KSTK_ESP(struct task_struct *task);

/*
 * User space RSP while inside the SYSCALL fast path
 */
DECLARE_PER_CPU(unsigned long, old_rsp);

#endif /* CONFIG_X86_64 */

extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
                                               unsigned long new_sp);

/*
 * This decides where the kernel will search for a free chunk of vm
 * space during mmap's.
 */
#define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 3))

#define KSTK_EIP(task)          (task_pt_regs(task)->ip)

/* Get/set a process' ability to use the timestamp counter instruction */
#define GET_TSC_CTL(adr)        get_tsc_mode((adr))
#define SET_TSC_CTL(val)        set_tsc_mode((val))

extern int get_tsc_mode(unsigned long adr);
extern int set_tsc_mode(unsigned int val);

extern u16 amd_get_nb_id(int cpu);

static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
{
        uint32_t base, eax, signature[3];

        for (base = 0x40000000; base < 0x40010000; base += 0x100) {
                cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);

                if (!memcmp(sig, signature, 12) &&
                    (leaves == 0 || ((eax - base) >= leaves)))
                        return base;
        }

        return 0;
}

extern unsigned long arch_align_stack(unsigned long sp);
extern void free_init_pages(char *what, unsigned long begin, unsigned long end);

void default_idle(void);
#ifdef  CONFIG_XEN
bool xen_set_default_idle(void);
#else
#define xen_set_default_idle 0
#endif

void stop_this_cpu(void *dummy);
void df_debug(struct pt_regs *regs, long error_code);
#endif /* _ASM_X86_PROCESSOR_H */
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root/arch/x86/include/asm/processor.h

INCLUDED FROM

DEFINITIONS
