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Diffstat (limited to 'include/asm-i386/system.h')
-rw-r--r--include/asm-i386/system.h31
1 files changed, 14 insertions, 17 deletions
diff --git a/include/asm-i386/system.h b/include/asm-i386/system.h
index 772f85da120..9c0593b7a94 100644
--- a/include/asm-i386/system.h
+++ b/include/asm-i386/system.h
@@ -54,23 +54,7 @@ __asm__ __volatile__ ("movw %%dx,%1\n\t" \
); } while(0)
#define set_base(ldt,base) _set_base( ((char *)&(ldt)) , (base) )
-#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1)>>12 )
-
-static inline unsigned long _get_base(char * addr)
-{
- unsigned long __base;
- __asm__("movb %3,%%dh\n\t"
- "movb %2,%%dl\n\t"
- "shll $16,%%edx\n\t"
- "movw %1,%%dx"
- :"=&d" (__base)
- :"m" (*((addr)+2)),
- "m" (*((addr)+4)),
- "m" (*((addr)+7)));
- return __base;
-}
-
-#define get_base(ldt) _get_base( ((char *)&(ldt)) )
+#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1) )
/*
* Load a segment. Fall back on loading the zero
@@ -140,6 +124,19 @@ static inline unsigned long _get_base(char * addr)
:"=r" (__dummy)); \
__dummy; \
})
+
+#define read_cr4_safe() ({ \
+ unsigned int __dummy; \
+ /* This could fault if %cr4 does not exist */ \
+ __asm__("1: movl %%cr4, %0 \n" \
+ "2: \n" \
+ ".section __ex_table,\"a\" \n" \
+ ".long 1b,2b \n" \
+ ".previous \n" \
+ : "=r" (__dummy): "0" (0)); \
+ __dummy; \
+})
+
#define write_cr4(x) \
__asm__ __volatile__("movl %0,%%cr4": :"r" (x));
#define stts() write_cr0(8 | read_cr0())