mirror of
https://github.com/torvalds/linux.git
synced 2024-11-15 16:41:58 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
361 lines
10 KiB
C
361 lines
10 KiB
C
/*
|
|
* PowerPC64 atomic bit operations.
|
|
* Dave Engebretsen, Todd Inglett, Don Reed, Pat McCarthy, Peter Bergner,
|
|
* Anton Blanchard
|
|
*
|
|
* Originally taken from the 32b PPC code. Modified to use 64b values for
|
|
* the various counters & memory references.
|
|
*
|
|
* Bitops are odd when viewed on big-endian systems. They were designed
|
|
* on little endian so the size of the bitset doesn't matter (low order bytes
|
|
* come first) as long as the bit in question is valid.
|
|
*
|
|
* Bits are "tested" often using the C expression (val & (1<<nr)) so we do
|
|
* our best to stay compatible with that. The assumption is that val will
|
|
* be unsigned long for such tests. As such, we assume the bits are stored
|
|
* as an array of unsigned long (the usual case is a single unsigned long,
|
|
* of course). Here's an example bitset with bit numbering:
|
|
*
|
|
* |63..........0|127........64|195.......128|255.......196|
|
|
*
|
|
* This leads to a problem. If an int, short or char is passed as a bitset
|
|
* it will be a bad memory reference since we want to store in chunks
|
|
* of unsigned long (64 bits here) size.
|
|
*
|
|
* There are a few little-endian macros used mostly for filesystem bitmaps,
|
|
* these work on similar bit arrays layouts, but byte-oriented:
|
|
*
|
|
* |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
|
|
*
|
|
* The main difference is that bit 3-5 in the bit number field needs to be
|
|
* reversed compared to the big-endian bit fields. This can be achieved
|
|
* by XOR with 0b111000 (0x38).
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef _PPC64_BITOPS_H
|
|
#define _PPC64_BITOPS_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <asm/memory.h>
|
|
|
|
/*
|
|
* clear_bit doesn't imply a memory barrier
|
|
*/
|
|
#define smp_mb__before_clear_bit() smp_mb()
|
|
#define smp_mb__after_clear_bit() smp_mb()
|
|
|
|
static __inline__ int test_bit(unsigned long nr, __const__ volatile unsigned long *addr)
|
|
{
|
|
return (1UL & (addr[nr >> 6] >> (nr & 63)));
|
|
}
|
|
|
|
static __inline__ void set_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long old;
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldarx %0,0,%3 # set_bit\n\
|
|
or %0,%0,%2\n\
|
|
stdcx. %0,0,%3\n\
|
|
bne- 1b"
|
|
: "=&r" (old), "=m" (*p)
|
|
: "r" (mask), "r" (p), "m" (*p)
|
|
: "cc");
|
|
}
|
|
|
|
static __inline__ void clear_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long old;
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldarx %0,0,%3 # clear_bit\n\
|
|
andc %0,%0,%2\n\
|
|
stdcx. %0,0,%3\n\
|
|
bne- 1b"
|
|
: "=&r" (old), "=m" (*p)
|
|
: "r" (mask), "r" (p), "m" (*p)
|
|
: "cc");
|
|
}
|
|
|
|
static __inline__ void change_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long old;
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldarx %0,0,%3 # change_bit\n\
|
|
xor %0,%0,%2\n\
|
|
stdcx. %0,0,%3\n\
|
|
bne- 1b"
|
|
: "=&r" (old), "=m" (*p)
|
|
: "r" (mask), "r" (p), "m" (*p)
|
|
: "cc");
|
|
}
|
|
|
|
static __inline__ int test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long old, t;
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: ldarx %0,0,%3 # test_and_set_bit\n\
|
|
or %1,%0,%2 \n\
|
|
stdcx. %1,0,%3 \n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
: "=&r" (old), "=&r" (t)
|
|
: "r" (mask), "r" (p)
|
|
: "cc", "memory");
|
|
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
static __inline__ int test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long old, t;
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: ldarx %0,0,%3 # test_and_clear_bit\n\
|
|
andc %1,%0,%2\n\
|
|
stdcx. %1,0,%3\n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
: "=&r" (old), "=&r" (t)
|
|
: "r" (mask), "r" (p)
|
|
: "cc", "memory");
|
|
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
static __inline__ int test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long old, t;
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
__asm__ __volatile__(
|
|
EIEIO_ON_SMP
|
|
"1: ldarx %0,0,%3 # test_and_change_bit\n\
|
|
xor %1,%0,%2\n\
|
|
stdcx. %1,0,%3\n\
|
|
bne- 1b"
|
|
ISYNC_ON_SMP
|
|
: "=&r" (old), "=&r" (t)
|
|
: "r" (mask), "r" (p)
|
|
: "cc", "memory");
|
|
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
static __inline__ void set_bits(unsigned long mask, unsigned long *addr)
|
|
{
|
|
unsigned long old;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldarx %0,0,%3 # set_bit\n\
|
|
or %0,%0,%2\n\
|
|
stdcx. %0,0,%3\n\
|
|
bne- 1b"
|
|
: "=&r" (old), "=m" (*addr)
|
|
: "r" (mask), "r" (addr), "m" (*addr)
|
|
: "cc");
|
|
}
|
|
|
|
/*
|
|
* non-atomic versions
|
|
*/
|
|
static __inline__ void __set_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
*p |= mask;
|
|
}
|
|
|
|
static __inline__ void __clear_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
*p &= ~mask;
|
|
}
|
|
|
|
static __inline__ void __change_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
|
|
*p ^= mask;
|
|
}
|
|
|
|
static __inline__ int __test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
unsigned long old = *p;
|
|
|
|
*p = old | mask;
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
static __inline__ int __test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
unsigned long old = *p;
|
|
|
|
*p = old & ~mask;
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
static __inline__ int __test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long mask = 1UL << (nr & 0x3f);
|
|
unsigned long *p = ((unsigned long *)addr) + (nr >> 6);
|
|
unsigned long old = *p;
|
|
|
|
*p = old ^ mask;
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
/*
|
|
* Return the zero-based bit position (from RIGHT TO LEFT, 63 -> 0) of the
|
|
* most significant (left-most) 1-bit in a double word.
|
|
*/
|
|
static __inline__ int __ilog2(unsigned long x)
|
|
{
|
|
int lz;
|
|
|
|
asm ("cntlzd %0,%1" : "=r" (lz) : "r" (x));
|
|
return 63 - lz;
|
|
}
|
|
|
|
/*
|
|
* Determines the bit position of the least significant (rightmost) 0 bit
|
|
* in the specified double word. The returned bit position will be zero-based,
|
|
* starting from the right side (63 - 0).
|
|
*/
|
|
static __inline__ unsigned long ffz(unsigned long x)
|
|
{
|
|
/* no zero exists anywhere in the 8 byte area. */
|
|
if ((x = ~x) == 0)
|
|
return 64;
|
|
|
|
/*
|
|
* Calculate the bit position of the least signficant '1' bit in x
|
|
* (since x has been changed this will actually be the least signficant
|
|
* '0' bit in * the original x). Note: (x & -x) gives us a mask that
|
|
* is the least significant * (RIGHT-most) 1-bit of the value in x.
|
|
*/
|
|
return __ilog2(x & -x);
|
|
}
|
|
|
|
static __inline__ int __ffs(unsigned long x)
|
|
{
|
|
return __ilog2(x & -x);
|
|
}
|
|
|
|
/*
|
|
* ffs: find first bit set. This is defined the same way as
|
|
* the libc and compiler builtin ffs routines, therefore
|
|
* differs in spirit from the above ffz (man ffs).
|
|
*/
|
|
static __inline__ int ffs(int x)
|
|
{
|
|
unsigned long i = (unsigned long)x;
|
|
return __ilog2(i & -i) + 1;
|
|
}
|
|
|
|
/*
|
|
* fls: find last (most-significant) bit set.
|
|
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
|
|
*/
|
|
#define fls(x) generic_fls(x)
|
|
|
|
/*
|
|
* hweightN: returns the hamming weight (i.e. the number
|
|
* of bits set) of a N-bit word
|
|
*/
|
|
#define hweight64(x) generic_hweight64(x)
|
|
#define hweight32(x) generic_hweight32(x)
|
|
#define hweight16(x) generic_hweight16(x)
|
|
#define hweight8(x) generic_hweight8(x)
|
|
|
|
extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, unsigned long offset);
|
|
#define find_first_zero_bit(addr, size) \
|
|
find_next_zero_bit((addr), (size), 0)
|
|
|
|
extern unsigned long find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset);
|
|
#define find_first_bit(addr, size) \
|
|
find_next_bit((addr), (size), 0)
|
|
|
|
extern unsigned long find_next_zero_le_bit(const unsigned long *addr, unsigned long size, unsigned long offset);
|
|
#define find_first_zero_le_bit(addr, size) \
|
|
find_next_zero_le_bit((addr), (size), 0)
|
|
|
|
static __inline__ int test_le_bit(unsigned long nr, __const__ unsigned long * addr)
|
|
{
|
|
__const__ unsigned char *ADDR = (__const__ unsigned char *) addr;
|
|
return (ADDR[nr >> 3] >> (nr & 7)) & 1;
|
|
}
|
|
|
|
#define test_and_clear_le_bit(nr, addr) \
|
|
test_and_clear_bit((nr) ^ 0x38, (addr))
|
|
#define test_and_set_le_bit(nr, addr) \
|
|
test_and_set_bit((nr) ^ 0x38, (addr))
|
|
|
|
/*
|
|
* non-atomic versions
|
|
*/
|
|
|
|
#define __set_le_bit(nr, addr) \
|
|
__set_bit((nr) ^ 0x38, (addr))
|
|
#define __clear_le_bit(nr, addr) \
|
|
__clear_bit((nr) ^ 0x38, (addr))
|
|
#define __test_and_clear_le_bit(nr, addr) \
|
|
__test_and_clear_bit((nr) ^ 0x38, (addr))
|
|
#define __test_and_set_le_bit(nr, addr) \
|
|
__test_and_set_bit((nr) ^ 0x38, (addr))
|
|
|
|
#define ext2_set_bit(nr,addr) \
|
|
__test_and_set_le_bit((nr), (unsigned long*)addr)
|
|
#define ext2_clear_bit(nr, addr) \
|
|
__test_and_clear_le_bit((nr), (unsigned long*)addr)
|
|
|
|
#define ext2_set_bit_atomic(lock, nr, addr) \
|
|
test_and_set_le_bit((nr), (unsigned long*)addr)
|
|
#define ext2_clear_bit_atomic(lock, nr, addr) \
|
|
test_and_clear_le_bit((nr), (unsigned long*)addr)
|
|
|
|
|
|
#define ext2_test_bit(nr, addr) test_le_bit((nr),(unsigned long*)addr)
|
|
#define ext2_find_first_zero_bit(addr, size) \
|
|
find_first_zero_le_bit((unsigned long*)addr, size)
|
|
#define ext2_find_next_zero_bit(addr, size, off) \
|
|
find_next_zero_le_bit((unsigned long*)addr, size, off)
|
|
|
|
#define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr)
|
|
#define minix_set_bit(nr,addr) set_bit(nr,addr)
|
|
#define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr)
|
|
#define minix_test_bit(nr,addr) test_bit(nr,addr)
|
|
#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _PPC64_BITOPS_H */
|