mirror of
https://github.com/torvalds/linux.git
synced 2024-12-21 02:21:36 +00:00
46 lines
1.2 KiB
C
46 lines
1.2 KiB
C
|
/* -*- linux-c -*- ------------------------------------------------------- *
|
||
|
*
|
||
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
||
|
* Copyright 2007 rPath, Inc. - All Rights Reserved
|
||
|
*
|
||
|
* This file is part of the Linux kernel, and is made available under
|
||
|
* the terms of the GNU General Public License version 2.
|
||
|
*
|
||
|
* ----------------------------------------------------------------------- */
|
||
|
|
||
|
/*
|
||
|
* arch/i386/boot/bitops.h
|
||
|
*
|
||
|
* Very simple bitops for the boot code.
|
||
|
*/
|
||
|
|
||
|
#ifndef BOOT_BITOPS_H
|
||
|
#define BOOT_BITOPS_H
|
||
|
#define _LINUX_BITOPS_H /* Inhibit inclusion of <linux/bitops.h> */
|
||
|
|
||
|
static inline int constant_test_bit(int nr, const void *addr)
|
||
|
{
|
||
|
const u32 *p = (const u32 *)addr;
|
||
|
return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0;
|
||
|
}
|
||
|
static inline int variable_test_bit(int nr, const void *addr)
|
||
|
{
|
||
|
u8 v;
|
||
|
const u32 *p = (const u32 *)addr;
|
||
|
|
||
|
asm("btl %2,%1; setc %0" : "=qm" (v) : "m" (*p), "Ir" (nr));
|
||
|
return v;
|
||
|
}
|
||
|
|
||
|
#define test_bit(nr,addr) \
|
||
|
(__builtin_constant_p(nr) ? \
|
||
|
constant_test_bit((nr),(addr)) : \
|
||
|
variable_test_bit((nr),(addr)))
|
||
|
|
||
|
static inline void set_bit(int nr, void *addr)
|
||
|
{
|
||
|
asm("btsl %1,%0" : "+m" (*(u32 *)addr) : "Ir" (nr));
|
||
|
}
|
||
|
|
||
|
#endif /* BOOT_BITOPS_H */
|