Re: [GIT PULL -tip v3] fix 39 'make headers_check' warnings

[Ingo Molnar <mingo@elte.hu>]

hm, i just noticed this detail:

commit 3521c5eef990515719614e212b26ea49e610d072
Author: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Date:   Sat Jan 17 19:25:46 2009 +0530

    headers_check fix: x86, swab.h
    
    fix the following 'make headers_check' warnings:
    
      usr/include/asm/swab.h:4: include of <linux/types.h> is preferred over <asm/types.h>
      usr/include/asm/swab.h:7: found __[us]{8,16,32,64} type without #include <linux/types.h>
      usr/include/asm/swab.h:10: leaks CONFIG_X86 to userspace where it is not valid
      usr/include/asm/swab.h:40: leaks CONFIG_X86 to userspace where it is not valid
    
    Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
    Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/include/asm/swab.h b/arch/x86/include/asm/swab.h
index 306d417..613be68 100644
--- a/arch/x86/include/asm/swab.h
+++ b/arch/x86/include/asm/swab.h
@@ -1,12 +1,15 @@
 #ifndef _ASM_X86_SWAB_H
 #define _ASM_X86_SWAB_H
 
-#include <asm/types.h>
+#include <linux/types.h>
+#ifdef __KERNEL__
 #include <linux/compiler.h>
+#endif /* __KERNEL__ */
 
 static inline __attribute_const__ __u32 __arch_swab32(__u32 val)
 {
 #ifdef __i386__
+#ifdef __KERNEL__
 # ifdef CONFIG_X86_BSWAP
 	asm("bswap %0" : "=r" (val) : "0" (val));
 # else
@@ -16,7 +19,13 @@ static inline __attribute_const__ __u32 __arch_swab32(__u32 val)
 	    : "=q" (val)
 	    : "0" (val));
 # endif
-
+#else /* __KERNEL__ */
+	asm("xchgb %b0,%h0\n\t"	/* swap lower bytes	*/
+	    "rorl $16,%0\n\t"	/* swap words		*/
+	    "xchgb %b0,%h0"	/* swap higher bytes	*/
+	    : "=q" (val)
+	    : "0" (val));
+#endif /* __KERNEL__ */
 #else /* __i386__ */
 	asm("bswapl %0"
 	    : "=r" (val)
@@ -37,6 +46,7 @@ static inline __attribute_const__ __u64 __arch_swab64(__u64 val)
 		__u64 u;
 	} v;
 	v.u = val;
+#ifdef __KERNEL__
 # ifdef CONFIG_X86_BSWAP
 	asm("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
 	    : "=r" (v.s.a), "=r" (v.s.b)
@@ -48,6 +58,13 @@ static inline __attribute_const__ __u64 __arch_swab64(__u64 val)
 	    : "=r" (v.s.a), "=r" (v.s.b)
 	    : "0" (v.s.a), "1" (v.s.b));
 # endif
+#else /* __KERNEL__ */
+	v.s.a = __arch_swab32(v.s.a);
+	v.s.b = __arch_swab32(v.s.b);
+	asm("xchgl %0,%1"
+	    : "=r" (v.s.a), "=r" (v.s.b)
+	    : "0" (v.s.a), "1" (v.s.b));
+#endif /* __KERNEL__ */
 	return v.u;
 #else /* __i386__ */
 	asm("bswapq %0"


why does such a change introduce new code? It is duplicating existing code 
instead of cleaning it all up.

	Ingo