diff options
author | Thomas Bushnell <thomas@gnu.org> | 1999-04-26 05:58:44 +0000 |
---|---|---|
committer | Thomas Bushnell <thomas@gnu.org> | 1999-04-26 05:58:44 +0000 |
commit | 86297c41a26f18d924e64fc93321c59cbc4c48dd (patch) | |
tree | 376954c6b95b735d361875319a1a2a9db6a27527 /linux/src/include/asm-i386/bitops.h | |
parent | 851137902d3e7ad87af177487df3eea53e940a1c (diff) | |
download | gnumach-86297c41a26f18d924e64fc93321c59cbc4c48dd.tar.gz gnumach-86297c41a26f18d924e64fc93321c59cbc4c48dd.tar.bz2 gnumach-86297c41a26f18d924e64fc93321c59cbc4c48dd.zip |
1998-11-30 OKUJI Yoshinori <okuji@kuicr.kyoto-u.ac.jp>
Clean up linux emulation code to make it architecture-independent
as much as possible.
* linux: Renamed from linuxdev.
* Makefile.in (objfiles): Add linux.o instead of linuxdev.o.
(MAKE): New variable. Used for the linux.o target.
* configure.in: Add AC_CHECK_TOOL(MAKE, make).
* i386/i386/spl.h: Include <i386/ipl.h>, for compatibility with
OSF Mach 3.0. Suggested by Elgin Lee <ehl@funghi.com>.
* linux/src: Renamed from linux/linux.
* linux/dev: Renamed from linux/mach.
* linux/Drivers.in (AC_INIT): Use dev/include/linux/autoconf.h,
instead of mach/include/linux/autoconf.h.
* Makefile.in (all): Target ../linux.o instead of ../linuxdev.o.
* linux/dev/drivers/block/genhd.c: Include <machine/spl.h> instead
of <i386/ipl.h>.
* linux/dev/drivers/net/auto_irq.c: Remove unneeded header files,
<i386/ipl.h> and <i386/pic.h>.
* linux/dev/init/main.c: Many i386-dependent codes moved to ...
* linux/dev/arch/i386/irq.c: ... here.
* linux/dev/arch/i386/setup.c: New file.
* linux/dev/arch/i386/linux_emul.h: Likewise.
* linux/dev/arch/i386/glue/timer.c: Merged into sched.c.
* linux/dev/arch/i386/glue/sched.c: Include <machine/spl.h> instead
of <i386/ipl.h>, and moved to ...
* linux/dev/kernel/sched.c: ... here.
* linux/dev/arch/i386/glue/block.c: Include <machine/spl.h> and
<linux_emul.h>, instead of i386-dependent header files, and
moved to ...
* linux/dev/glue/blocl.c: ... here.
* linux/dev/arch/i386/glue/net.c: Include <machine/spl.h> and
<linux_emul.h>, instead of i386-dependent header files, and
moved to ...
* linux/dev/glue/net.c: ... here.
* linux/dev/arch/i386/glue/misc.c: Remove `x86' and moved to ...
* linux/dev/glue/misc.c: ... here.
* linux/dev/arch/i386/glue/kmem.c: Moved to ...
* linux/dev/glue/kmem.c: ... here.
Diffstat (limited to 'linux/src/include/asm-i386/bitops.h')
-rw-r--r-- | linux/src/include/asm-i386/bitops.h | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/linux/src/include/asm-i386/bitops.h b/linux/src/include/asm-i386/bitops.h new file mode 100644 index 00000000..e3ea8f54 --- /dev/null +++ b/linux/src/include/asm-i386/bitops.h @@ -0,0 +1,137 @@ +#ifndef _I386_BITOPS_H +#define _I386_BITOPS_H + +/* + * Copyright 1992, Linus Torvalds. + */ + +/* + * These have to be done with inline assembly: that way the bit-setting + * is guaranteed to be atomic. All bit operations return 0 if the bit + * was cleared before the operation and != 0 if it was not. + * + * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). + */ + +#ifdef __SMP__ +#define LOCK_PREFIX "lock ; " +#define SMPVOL volatile +#else +#define LOCK_PREFIX "" +#define SMPVOL +#endif + +/* + * Some hacks to defeat gcc over-optimizations.. + */ +struct __dummy { unsigned long a[100]; }; +#define ADDR (*(struct __dummy *) addr) +#define CONST_ADDR (*(const struct __dummy *) addr) + +extern __inline__ int set_bit(int nr, SMPVOL void * addr) +{ + int oldbit; + + __asm__ __volatile__(LOCK_PREFIX + "btsl %2,%1\n\tsbbl %0,%0" + :"=r" (oldbit),"=m" (ADDR) + :"ir" (nr)); + return oldbit; +} + +extern __inline__ int clear_bit(int nr, SMPVOL void * addr) +{ + int oldbit; + + __asm__ __volatile__(LOCK_PREFIX + "btrl %2,%1\n\tsbbl %0,%0" + :"=r" (oldbit),"=m" (ADDR) + :"ir" (nr)); + return oldbit; +} + +extern __inline__ int change_bit(int nr, SMPVOL void * addr) +{ + int oldbit; + + __asm__ __volatile__(LOCK_PREFIX + "btcl %2,%1\n\tsbbl %0,%0" + :"=r" (oldbit),"=m" (ADDR) + :"ir" (nr)); + return oldbit; +} + +/* + * This routine doesn't need to be atomic. + */ +extern __inline__ int test_bit(int nr, const SMPVOL void * addr) +{ + return ((1UL << (nr & 31)) & (((const unsigned int *) addr)[nr >> 5])) != 0; +} + +/* + * Find-bit routines.. + */ +extern __inline__ int find_first_zero_bit(void * addr, unsigned size) +{ + int res; + + if (!size) + return 0; + __asm__("cld\n\t" + "movl $-1,%%eax\n\t" + "xorl %%edx,%%edx\n\t" + "repe; scasl\n\t" + "je 1f\n\t" + "xorl -4(%%edi),%%eax\n\t" + "subl $4,%%edi\n\t" + "bsfl %%eax,%%edx\n" + "1:\tsubl %%ebx,%%edi\n\t" + "shll $3,%%edi\n\t" + "addl %%edi,%%edx" + :"=d" (res) + :"c" ((size + 31) >> 5), "D" (addr), "b" (addr) + :"ax", "cx", "di"); + return res; +} + +extern __inline__ int find_next_zero_bit (void * addr, int size, int offset) +{ + unsigned long * p = ((unsigned long *) addr) + (offset >> 5); + int set = 0, bit = offset & 31, res; + + if (bit) { + /* + * Look for zero in first byte + */ + __asm__("bsfl %1,%0\n\t" + "jne 1f\n\t" + "movl $32, %0\n" + "1:" + : "=r" (set) + : "r" (~(*p >> bit))); + if (set < (32 - bit)) + return set + offset; + set = 32 - bit; + p++; + } + /* + * No zero yet, search remaining full bytes for a zero + */ + res = find_first_zero_bit (p, size - 32 * (p - (unsigned long *) addr)); + return (offset + set + res); +} + +/* + * ffz = Find First Zero in word. Undefined if no zero exists, + * so code should check against ~0UL first.. + */ +extern __inline__ unsigned long ffz(unsigned long word) +{ + __asm__("bsfl %1,%0" + :"=r" (word) + :"r" (~word)); + return word; +} + +#endif /* _I386_BITOPS_H */ |