kolibrios-fun/drivers/include/asm/processor.h

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#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;
struct vm86;
#include <asm/math_emu.h>
#include <asm/segment.h>
#include <asm/types.h>
#include <uapi/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 <asm/fpu/types.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;
}
/*
* These alignment constraints are for performance in the vSMP case,
* but in the task_struct case we must also meet hardware imposed
* alignment requirements of the FPU state:
*/
#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 */
/* Cache QoS architectural values: */
int x86_cache_max_rmid; /* max index */
int x86_cache_occ_scale; /* scale to 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;
};
#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_READ_MOSTLY(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;
extern void cpu_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;
/*
* We don't use ring 1, so ss1 is a convenient scratch space in
* the same cacheline as sp0. We use ss1 to cache the value in
* MSR_IA32_SYSENTER_CS. When we context switch
* MSR_IA32_SYSENTER_CS, we first check if the new value being
* written matches ss1, and, if it's not, then we wrmsr the new
* value and update ss1.
*
* The only reason we context switch MSR_IA32_SYSENTER_CS is
* that we set it to zero in vm86 tasks to avoid corrupting the
* stack if we were to go through the sysenter path from vm86
* mode.
*/
unsigned short ss1; /* MSR_IA32_SYSENTER_CS */
unsigned short __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];
/*
* Space for the temporary SYSENTER stack:
*/
unsigned long SYSENTER_stack[64];
} ____cacheline_aligned;
DECLARE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss);
#ifdef CONFIG_X86_32
DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
#endif
/*
* Save the original ist values for checking stack pointers during debugging
*/
struct orig_ist {
unsigned long ist[7];
};
#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;
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 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;
#ifdef CONFIG_VM86
/* Virtual 86 mode info */
struct vm86 *vm86;
#endif
/* IO permissions: */
unsigned long *io_bitmap_ptr;
unsigned long iopl;
/* Max allowed port in the bitmap, in bytes: */
unsigned io_bitmap_max;
/* Floating point and extended processor state */
struct fpu fpu;
/*
* WARNING: 'fpu' is dynamically-sized. It *MUST* be at
* the end.
*/
};
/*
* 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
#define paravirt_has(x) 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 */
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 __always_inline void rep_nop(void)
{
asm volatile("rep; nop" ::: "memory");
}
static __always_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);
/* 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 ""
# define ARCH_HAS_PREFETCH
#else
# define BASE_PREFETCH "prefetcht0 %P1"
#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);
}
#define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
TOP_OF_KERNEL_STACK_PADDING)
#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 = TOP_OF_INIT_STACK, \
.sysenter_cs = __KERNEL_CS, \
.io_bitmap_ptr = NULL, \
}
extern unsigned long thread_saved_pc(struct task_struct *tsk);
/*
* TOP_OF_KERNEL_STACK_PADDING reserves 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) \
({ \
unsigned long __ptr = (unsigned long)task_stack_page(task); \
__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING; \
((struct pt_regs *)__ptr) - 1; \
})
#define KSTK_ESP(task) (task_pt_regs(task)->sp)
#else
/*
* User space process size. 47bits minus one guard page. The guard
* page is necessary on Intel CPUs: if a SYSCALL instruction is at
* the highest possible canonical userspace address, then that
* syscall will enter the kernel with a non-canonical return
* address, and SYSRET will explode dangerously. We avoid this
* particular problem by preventing anything from being mapped
* at the maximum canonical address.
*/
#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 = TOP_OF_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);
#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);
/* Register/unregister a process' MPX related resource */
#define MPX_ENABLE_MANAGEMENT() mpx_enable_management()
#define MPX_DISABLE_MANAGEMENT() mpx_disable_management()
#ifdef CONFIG_X86_INTEL_MPX
extern int mpx_enable_management(void);
extern int mpx_disable_management(void);
#else
static inline int mpx_enable_management(void)
{
return -EINVAL;
}
static inline int mpx_disable_management(void)
{
return -EINVAL;
}
#endif /* CONFIG_X86_INTEL_MPX */
extern u16 amd_get_nb_id(int cpu);
extern u32 amd_get_nodes_per_socket(void);
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 */