[PATCH] i386: rationalize paravirt wrappers

paravirt.c used to implement native versions of all low-level
functions.  Far cleaner is to have the native versions exposed in the
headers and as inline native_XXX, and if !CONFIG_PARAVIRT, then simply
#define XXX native_XXX.

There are several nice side effects:

1) write_dt_entry() now takes the correct "struct Xgt_desc_struct *"
   not "void *".

2) load_TLS is reintroduced to the for loop, not manually unrolled
   with a #error in case the bounds ever change.

3) Macros become inlines, with type checking.

4) Access to the native versions is trivial for KVM, lguest, Xen and
   others who might want it.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@muc.de>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 110 insertions, 53 deletions

diff --git a/include/asm-i386/msr.h b/include/asm-i386/msr.h
index 2ad3f30b1a68..00acaa8b36bb 100644
--- a/include/asm-i386/msr.h
+++ b/include/asm-i386/msr.h
@@ -1,6 +1,74 @@
 #ifndef __ASM_MSR_H
 #define __ASM_MSR_H
 
+#include <asm/errno.h>
+
+static inline unsigned long long native_read_msr(unsigned int msr)
+{
+	unsigned long long val;
+
+	asm volatile("rdmsr" : "=A" (val) : "c" (msr));
+	return val;
+}
+
+static inline unsigned long long native_read_msr_safe(unsigned int msr,
+						      int *err)
+{
+	unsigned long long val;
+
+	asm volatile("2: rdmsr ; xorl %0,%0\n"
+		     "1:\n\t"
+		     ".section .fixup,\"ax\"\n\t"
+		     "3:  movl %3,%0 ; jmp 1b\n\t"
+		     ".previous\n\t"
+ 		     ".section __ex_table,\"a\"\n"
+		     "   .align 4\n\t"
+		     "   .long 	2b,3b\n\t"
+		     ".previous"
+		     : "=r" (*err), "=A" (val)
+		     : "c" (msr), "i" (-EFAULT));
+
+	return val;
+}
+
+static inline void native_write_msr(unsigned int msr, unsigned long long val)
+{
+	asm volatile("wrmsr" : : "c" (msr), "A"(val));
+}
+
+static inline int native_write_msr_safe(unsigned int msr,
+					unsigned long long val)
+{
+	int err;
+	asm volatile("2: wrmsr ; xorl %0,%0\n"
+		     "1:\n\t"
+		     ".section .fixup,\"ax\"\n\t"
+		     "3:  movl %4,%0 ; jmp 1b\n\t"
+		     ".previous\n\t"
+ 		     ".section __ex_table,\"a\"\n"
+		     "   .align 4\n\t"
+		     "   .long 	2b,3b\n\t"
+		     ".previous"
+		     : "=a" (err)
+		     : "c" (msr), "0" ((u32)val), "d" ((u32)(val>>32)),
+		       "i" (-EFAULT));
+	return err;
+}
+
+static inline unsigned long long native_read_tsc(void)
+{
+	unsigned long long val;
+	asm volatile("rdtsc" : "=A" (val));
+	return val;
+}
+
+static inline unsigned long long native_read_pmc(void)
+{
+	unsigned long long val;
+	asm volatile("rdpmc" : "=A" (val));
+	return val;
+}
+
 #ifdef CONFIG_PARAVIRT
 #include <asm/paravirt.h>
 #else
@@ -11,22 +79,20 @@
  * pointer indirection), this allows gcc to optimize better
  */
 
-#define rdmsr(msr,val1,val2) \
-	__asm__ __volatile__("rdmsr" \
-			  : "=a" (val1), "=d" (val2) \
-			  : "c" (msr))
+#define rdmsr(msr,val1,val2)						\
+	do {								\
+		unsigned long long __val = native_read_msr(msr);	\
+		val1 = __val;						\
+		val2 = __val >> 32;					\
+	} while(0)
 
-#define wrmsr(msr,val1,val2) \
-	__asm__ __volatile__("wrmsr" \
-			  : /* no outputs */ \
-			  : "c" (msr), "a" (val1), "d" (val2))
+#define wrmsr(msr,val1,val2)						\
+	native_write_msr(msr, ((unsigned long long)val2 << 32) | val1)
 
-#define rdmsrl(msr,val) do { \
-	unsigned long l__,h__; \
-	rdmsr (msr, l__, h__);  \
-	val = l__;  \
-	val |= ((u64)h__<<32);  \
-} while(0)
+#define rdmsrl(msr,val)					\
+	do {						\
+		(val) = native_read_msr(msr);		\
+	} while(0)
 
 static inline void wrmsrl (unsigned long msr, unsigned long long val)
 {
@@ -37,50 +103,41 @@ static inline void wrmsrl (unsigned long msr, unsigned long long val)
 }
 
 /* wrmsr with exception handling */
-#define wrmsr_safe(msr,a,b) ({ int ret__;						\
-	asm volatile("2: wrmsr ; xorl %0,%0\n"						\
-		     "1:\n\t"								\
-		     ".section .fixup,\"ax\"\n\t"					\
-		     "3:  movl %4,%0 ; jmp 1b\n\t"					\
-		     ".previous\n\t"							\
- 		     ".section __ex_table,\"a\"\n"					\
-		     "   .align 4\n\t"							\
-		     "   .long 	2b,3b\n\t"						\
-		     ".previous"							\
-		     : "=a" (ret__)							\
-		     : "c" (msr), "0" (a), "d" (b), "i" (-EFAULT));\
-	ret__; })
+#define wrmsr_safe(msr,val1,val2)						\
+	(native_write_msr_safe(msr, ((unsigned long long)val2 << 32) | val1))
 
 /* rdmsr with exception handling */
-#define rdmsr_safe(msr,a,b) ({ int ret__;						\
-	asm volatile("2: rdmsr ; xorl %0,%0\n"						\
-		     "1:\n\t"								\
-		     ".section .fixup,\"ax\"\n\t"					\
-		     "3:  movl %4,%0 ; jmp 1b\n\t"					\
-		     ".previous\n\t"							\
- 		     ".section __ex_table,\"a\"\n"					\
-		     "   .align 4\n\t"							\
-		     "   .long 	2b,3b\n\t"						\
-		     ".previous"							\
-		     : "=r" (ret__), "=a" (*(a)), "=d" (*(b))				\
-		     : "c" (msr), "i" (-EFAULT));\
-	ret__; })
-
-#define rdtsc(low,high) \
-     __asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high))
-
-#define rdtscl(low) \
-     __asm__ __volatile__("rdtsc" : "=a" (low) : : "edx")
-
-#define rdtscll(val) \
-     __asm__ __volatile__("rdtsc" : "=A" (val))
+#define rdmsr_safe(msr,p1,p2)						\
+	({								\
+		int __err;						\
+		unsigned long long __val = native_read_msr_safe(msr, &__err);\
+		(*p1) = __val;						\
+		(*p2) = __val >> 32;					\
+		__err;							\
+	})
+
+#define rdtsc(low,high)						\
+	do {							\
+		u64 _l = native_read_tsc();			\
+		(low) = (u32)_l;				\
+		(high) = _l >> 32;				\
+	} while(0)
+
+#define rdtscl(low)						\
+	do {							\
+		(low) = native_read_tsc();			\
+	} while(0)
+
+#define rdtscll(val) ((val) = native_read_tsc())
 
 #define write_tsc(val1,val2) wrmsr(0x10, val1, val2)
 
-#define rdpmc(counter,low,high) \
-     __asm__ __volatile__("rdpmc" \
-			  : "=a" (low), "=d" (high) \
-			  : "c" (counter))
+#define rdpmc(counter,low,high)					\
+	do {							\
+		u64 _l = native_read_pmc();			\
+		low = (u32)_l;					\
+		high = _l >> 32;				\
+	} while(0)
 #endif	/* !CONFIG_PARAVIRT */
 
 #ifdef CONFIG_SMP