#ifndef _ASM_X86_SPECIAL_INSNS_H
#define _ASM_X86_SPECIAL_INSNS_H
#ifdef __KERNEL__
#include <asm/nops.h>
static inline void native_clts(void)
{
asm volatile("clts");
}
/*
* Volatile isn't enough to prevent the compiler from reordering the
* read/write functions for the control registers and messing everything up.
* A memory clobber would solve the problem, but would prevent reordering of
* all loads stores around it, which can hurt performance. Solution is to
* use a variable and mimic reads and writes to it to enforce serialization
*/
extern unsigned long __force_order;
static inline unsigned long native_read_cr0(void)
{
unsigned long val;
asm volatile("mov %%cr0,%0\n\t" : "=r" (val), "=m" (__force_order));
return val;
}
static inline void native_write_cr0(unsigned long val)
{
asm volatile("mov %0,%%cr0": : "r" (val), "m" (__force_order));
}
static inline unsigned long native_read_cr2(void)
{
unsigned long val;
asm volatile("mov %%cr2,%0\n\t" : "=r" (val), "=m" (__force_order));
return val;
}
static inline void native_write_cr2(unsigned long val)
{
asm volatile("mov %0,%%cr2": : "r" (val), "m" (__force_order));
}
static inline unsigned long native_read_cr3(void)
{
unsigned long val;
asm volatile("mov %%cr3,%0\n\t" : "=r" (val), "=m" (__force_order));
return val;
}
static inline void native_write_cr3(unsigned long val)
{
asm volatile("mov %0,%%cr3": : "r" (val), "m" (__force_order));
}
static inline unsigned long native_read_cr4(void)
{
unsigned long val;
asm volatile("mov %%cr4,%0\n\t" : "=r" (val), "=m" (__force_order));
return val;
}
static inline unsigned long native_read_cr4_safe(void)
{
unsigned long val;
/* This could fault if %cr4 does not exist. In x86_64, a cr4 always
* exists, so it will never fail. */
#ifdef CONFIG_X86_32
asm volatile("1: mov %%cr4, %0\n"
"2:\n"
_ASM_EXTABLE(1b, 2b)
: "=r" (val), "=m" (__force_order) : "0" (0));
#else
val = native_read_cr4();
#endif
return val;
}
static inline void native_write_cr4(unsigned long val)
{
asm volatile("mov %0,%%cr4": : "r" (val), "m" (__force_order));
}
#ifdef CONFIG_X86_64
static inline unsigned long native_read_cr8(void)
{
unsigned long cr8;
asm volatile("movq %%cr8,%0" : "=r" (cr8));
return cr8;
}
static inline void native_write_cr8(unsigned long val)
{
asm volatile("movq %0,%%cr8" :: "r" (val) : "memory");
}
#endif
#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
static inline u32 __read_pkru(void)
{
u32 ecx = 0;
u32 edx, pkru;
/*
* "rdpkru" instruction. Places PKRU contents in to EAX,
* clears EDX and requires that ecx=0.
*/
asm volatile(".byte 0x0f,0x01,0xee\n\t"
: "=a" (pkru), "=d" (edx)
: "c" (ecx));
return pkru;
}
static inline void __write_pkru(u32 pkru)
{
u32 ecx = 0, edx = 0;
/*
* "wrpkru" instruction. Loads contents in EAX to PKRU,
* requires that ecx = edx = 0.
*/
asm volatile(".byte 0x0f,0x01,0xef\n\t"
: : "a" (pkru), "c"(ecx), "d"(edx));
}
#else
static inline u32 __read_pkru(void)
{
return 0;
}
static inline void __write_pkru(u32 pkru)
{
}
#endif
static inline void native_wbinvd(void)
{
asm volatile("wbinvd": : :"memory");
}
extern asmlinkage void native_load_gs_index(unsigned);
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
static inline unsigned long read_cr0(void)
{
return native_read_cr0();
}
static inline void write_cr0(unsigned long x)
{
native_write_cr0(x);
}
static inline unsigned long read_cr2(void)
{
return native_read_cr2();
}
static inline void write_cr2(unsigned long x)
{
native_write_cr2(x);
}
static inline unsigned long read_cr3(void)
{
return native_read_cr3();
}
static inline void write_cr3(unsigned long x)
{
native_write_cr3(x);
}
static inline unsigned long __read_cr4(void)
{
return native_read_cr4();
}
static inline unsigned long __read_cr4_safe(void)
{
return native_read_cr4_safe();
}
static inline void __write_cr4(unsigned long x)
{
native_write_cr4(x);
}
static inline void wbinvd(void)
{
native_wbinvd();
}
#ifdef CONFIG_X86_64
static inline unsigned long read_cr8(void)
{
return native_read_cr8();
}
static inline void write_cr8(unsigned long x)
{
native_write_cr8(x);
}
static inline void load_gs_index(unsigned selector)
{
native_load_gs_index(selector);
}
#endif
/* Clear the 'TS' bit */
static inline void clts(void)
{
native_clts();
}
#endif/* CONFIG_PARAVIRT */
#define stts() write_cr0(read_cr0() | X86_CR0_TS)
static inline void clflush(volatile void *__p)
{
asm volatile("clflush %0" : "+m" (*(volatile char __force *)__p));
}
static inline void clflushopt(volatile void *__p)
{
alternative_io(".byte " __stringify(NOP_DS_PREFIX) "; clflush %P0",
".byte 0x66; clflush %P0",
X86_FEATURE_CLFLUSHOPT,
"+m" (*(volatile char __force *)__p));
}
#define nop() asm volatile ("nop")
#endif /* __KERNEL__ */
#endif /* _ASM_X86_SPECIAL_INSNS_H */