linux/arch/parisc/include/uapi/asm/swab.h
Helge Deller 2ad5d52d42 parisc: Don't use BITS_PER_LONG in userspace-exported swab.h header
In swab.h the "#if BITS_PER_LONG > 32" breaks compiling userspace programs if
BITS_PER_LONG is #defined by userspace with the sizeof() compiler builtin.

Solve this problem by using __BITS_PER_LONG instead.  Since we now
#include asm/bitsperlong.h avoid further potential userspace pollution
by moving the #define of SHIFT_PER_LONG to bitops.h which is not
exported to userspace.

This patch unbreaks compiling qemu on hppa/parisc.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
2017-01-28 21:54:23 +01:00

68 lines
1.7 KiB
C

#ifndef _PARISC_SWAB_H
#define _PARISC_SWAB_H
#include <asm/bitsperlong.h>
#include <linux/types.h>
#include <linux/compiler.h>
#define __SWAB_64_THRU_32__
static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
{
__asm__("dep %0, 15, 8, %0\n\t" /* deposit 00ab -> 0bab */
"shd %%r0, %0, 8, %0" /* shift 000000ab -> 00ba */
: "=r" (x)
: "0" (x));
return x;
}
#define __arch_swab16 __arch_swab16
static inline __attribute_const__ __u32 __arch_swab24(__u32 x)
{
__asm__("shd %0, %0, 8, %0\n\t" /* shift xabcxabc -> cxab */
"dep %0, 15, 8, %0\n\t" /* deposit cxab -> cbab */
"shd %%r0, %0, 8, %0" /* shift 0000cbab -> 0cba */
: "=r" (x)
: "0" (x));
return x;
}
static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
{
unsigned int temp;
__asm__("shd %0, %0, 16, %1\n\t" /* shift abcdabcd -> cdab */
"dep %1, 15, 8, %1\n\t" /* deposit cdab -> cbab */
"shd %0, %1, 8, %0" /* shift abcdcbab -> dcba */
: "=r" (x), "=&r" (temp)
: "0" (x));
return x;
}
#define __arch_swab32 __arch_swab32
#if __BITS_PER_LONG > 32
/*
** From "PA-RISC 2.0 Architecture", HP Professional Books.
** See Appendix I page 8 , "Endian Byte Swapping".
**
** Pretty cool algorithm: (* == zero'd bits)
** PERMH 01234567 -> 67452301 into %0
** HSHL 67452301 -> 7*5*3*1* into %1
** HSHR 67452301 -> *6*4*2*0 into %0
** OR %0 | %1 -> 76543210 into %0 (all done!)
*/
static inline __attribute_const__ __u64 __arch_swab64(__u64 x)
{
__u64 temp;
__asm__("permh,3210 %0, %0\n\t"
"hshl %0, 8, %1\n\t"
"hshr,u %0, 8, %0\n\t"
"or %1, %0, %0"
: "=r" (x), "=&r" (temp)
: "0" (x));
return x;
}
#define __arch_swab64 __arch_swab64
#endif /* __BITS_PER_LONG > 32 */
#endif /* _PARISC_SWAB_H */