freebsd-nq/sys/ofed/include/linux/bitops.h
2011-03-21 09:58:24 +00:00

313 lines
6.4 KiB
C

/*-
* Copyright (c) 2010 Isilon Systems, Inc.
* Copyright (c) 2010 iX Systems, Inc.
* Copyright (c) 2010 Panasas, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _LINUX_BITOPS_H_
#define _LINUX_BITOPS_H_
#ifdef __LP64__
#define BITS_PER_LONG 64
#else
#define BITS_PER_LONG 32
#endif
#define BIT_MASK(n) (~0UL >> (BITS_PER_LONG - (n)))
#define BITS_TO_LONGS(n) howmany((n), BITS_PER_LONG)
static inline int
__ffs(int mask)
{
return (ffs(mask) - 1);
}
static inline int
__fls(int mask)
{
return (fls(mask) - 1);
}
static inline int
__ffsl(long mask)
{
return (ffsl(mask) - 1);
}
static inline int
__flsl(long mask)
{
return (flsl(mask) - 1);
}
#define ffz(mask) __ffs(~(mask))
static inline unsigned long
find_first_bit(unsigned long *addr, unsigned long size)
{
long mask;
int bit;
for (bit = 0; size >= BITS_PER_LONG;
size -= BITS_PER_LONG, bit += BITS_PER_LONG, addr++) {
if (*addr == 0)
continue;
return (bit + __ffsl(*addr));
}
if (size) {
mask = (*addr) & BIT_MASK(size);
if (mask)
bit += __ffsl(mask);
else
bit += size;
}
return (bit);
}
static inline unsigned long
find_first_zero_bit(unsigned long *addr, unsigned long size)
{
long mask;
int bit;
for (bit = 0; size >= BITS_PER_LONG;
size -= BITS_PER_LONG, bit += BITS_PER_LONG, addr++) {
if (~(*addr) == 0)
continue;
return (bit + __ffsl(~(*addr)));
}
if (size) {
mask = ~(*addr) & BIT_MASK(size);
if (mask)
bit += __ffsl(mask);
else
bit += size;
}
return (bit);
}
static inline unsigned long
find_last_bit(unsigned long *addr, unsigned long size)
{
long mask;
int offs;
int bit;
int pos;
pos = size / BITS_PER_LONG;
offs = size % BITS_PER_LONG;
bit = BITS_PER_LONG * pos;
addr += pos;
if (offs) {
mask = (*addr) & BIT_MASK(offs);
if (mask)
return (bit + __flsl(mask));
}
while (--pos) {
addr--;
bit -= BITS_PER_LONG;
if (*addr)
return (bit + __flsl(mask));
}
return (size);
}
static inline unsigned long
find_next_bit(unsigned long *addr, unsigned long size, unsigned long offset)
{
long mask;
int offs;
int bit;
int pos;
if (offset >= size)
return (size);
pos = offset / BITS_PER_LONG;
offs = offset % BITS_PER_LONG;
bit = BITS_PER_LONG * pos;
addr += pos;
if (offs) {
mask = (*addr) & ~BIT_MASK(offs);
if (mask)
return (bit + __ffsl(mask));
bit += BITS_PER_LONG;
addr++;
}
for (size -= bit; size >= BITS_PER_LONG;
size -= BITS_PER_LONG, bit += BITS_PER_LONG, addr++) {
if (*addr == 0)
continue;
return (bit + __ffsl(*addr));
}
if (size) {
mask = (*addr) & BIT_MASK(size);
if (mask)
bit += __ffsl(mask);
else
bit += size;
}
return (bit);
}
static inline unsigned long
find_next_zero_bit(unsigned long *addr, unsigned long size,
unsigned long offset)
{
long mask;
int offs;
int bit;
int pos;
if (offset >= size)
return (size);
pos = offset / BITS_PER_LONG;
offs = offset % BITS_PER_LONG;
bit = BITS_PER_LONG * pos;
addr += pos;
if (offs) {
mask = ~(*addr) & ~BIT_MASK(offs);
if (mask)
return (bit + __ffsl(mask));
bit += BITS_PER_LONG;
addr++;
}
for (size -= bit; size >= BITS_PER_LONG;
size -= BITS_PER_LONG, bit += BITS_PER_LONG, addr++) {
if (~(*addr) == 0)
continue;
return (bit + __ffsl(~(*addr)));
}
if (size) {
mask = ~(*addr) & BIT_MASK(size);
if (mask)
bit += __ffsl(mask);
else
bit += size;
}
return (bit);
}
static inline void
bitmap_zero(unsigned long *addr, int size)
{
int len;
len = BITS_TO_LONGS(size) * sizeof(long);
memset(addr, 0, len);
}
static inline void
bitmap_fill(unsigned long *addr, int size)
{
int tail;
int len;
len = (size / BITS_PER_LONG) * sizeof(long);
memset(addr, 0xff, len);
tail = size & (BITS_PER_LONG - 1);
if (tail)
addr[size / BITS_PER_LONG] = BIT_MASK(tail);
}
static inline int
bitmap_full(unsigned long *addr, int size)
{
long mask;
int tail;
int len;
int i;
len = size / BITS_PER_LONG;
for (i = 0; i < len; i++)
if (addr[i] != ~0UL)
return (0);
tail = size & (BITS_PER_LONG - 1);
if (tail) {
mask = BIT_MASK(tail);
if ((addr[i] & mask) != mask)
return (0);
}
return (1);
}
static inline int
bitmap_empty(unsigned long *addr, int size)
{
long mask;
int tail;
int len;
int i;
len = size / BITS_PER_LONG;
for (i = 0; i < len; i++)
if (addr[i] != 0)
return (0);
tail = size & (BITS_PER_LONG - 1);
if (tail) {
mask = BIT_MASK(tail);
if ((addr[i] & mask) != 0)
return (0);
}
return (1);
}
#define NBINT (NBBY * sizeof(int))
#define set_bit(i, a) \
atomic_set_int(&((volatile int *)(a))[(i)/NBINT], 1 << (i) % NBINT)
#define clear_bit(i, a) \
atomic_clear_int(&((volatile int *)(a))[(i)/NBINT], 1 << (i) % NBINT)
#define test_bit(i, a) \
!!(atomic_load_acq_int(&((volatile int *)(a))[(i)/NBINT]) & 1 << ((i) % NBINT))
static inline long
test_and_clear_bit(long bit, long *var)
{
long val;
bit = 1 << bit;
do {
val = *(volatile long *)var;
} while (atomic_cmpset_long(var, val, val & ~bit) == 0);
return !!(val & bit);
}
static inline long
test_and_set_bit(long bit, long *var)
{
long val;
bit = 1 << bit;
do {
val = *(volatile long *)var;
} while (atomic_cmpset_long(var, val, val | bit) == 0);
return !!(val & bit);
}
#endif /* _LINUX_BITOPS_H_ */