freebsd-dev/sys/compat/linuxkpi/common/include/linux/bitops.h

507 lines
11 KiB
C
Raw Normal View History

/*-
* Copyright (c) 2010 Isilon Systems, Inc.
* Copyright (c) 2010 iX Systems, Inc.
* Copyright (c) 2010 Panasas, Inc.
* Copyright (c) 2013-2015 Mellanox Technologies, Ltd.
* 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.
*
* $FreeBSD$
*/
#ifndef _LINUX_BITOPS_H_
#define _LINUX_BITOPS_H_
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/errno.h>
#define BIT(nr) (1UL << (nr))
#ifdef __LP64__
#define BITS_PER_LONG 64
#else
#define BITS_PER_LONG 32
#endif
#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG))
#define BITMAP_LAST_WORD_MASK(n) (~0UL >> (BITS_PER_LONG - (n)))
#define BITS_TO_LONGS(n) howmany((n), BITS_PER_LONG)
#define BIT_MASK(nr) (1UL << ((nr) & (BITS_PER_LONG - 1)))
#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
#define GENMASK(lo, hi) (((2UL << ((hi) - (lo))) - 1UL) << (lo))
#define BITS_PER_BYTE 8
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 int get_count_order(unsigned int count)
{
int order;
order = fls(count) - 1;
if (count & (count - 1))
order++;
return order;
}
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) & BITMAP_LAST_WORD_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) & BITMAP_LAST_WORD_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) & BITMAP_LAST_WORD_MASK(offs);
if (mask)
return (bit + __flsl(mask));
}
while (pos--) {
addr--;
bit -= BITS_PER_LONG;
if (*addr)
return (bit + __flsl(*addr));
}
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) & ~BITMAP_LAST_WORD_MASK(offs);
if (mask)
return (bit + __ffsl(mask));
if (size - bit <= BITS_PER_LONG)
return (size);
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) & BITMAP_LAST_WORD_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) & ~BITMAP_LAST_WORD_MASK(offs);
if (mask)
return (bit + __ffsl(mask));
if (size - bit <= BITS_PER_LONG)
return (size);
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) & BITMAP_LAST_WORD_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] = BITMAP_LAST_WORD_MASK(tail);
}
static inline int
bitmap_full(unsigned long *addr, int size)
{
unsigned 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 = BITMAP_LAST_WORD_MASK(tail);
if ((addr[i] & mask) != mask)
return (0);
}
return (1);
}
static inline int
bitmap_empty(unsigned long *addr, int size)
{
unsigned 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 = BITMAP_LAST_WORD_MASK(tail);
if ((addr[i] & mask) != 0)
return (0);
}
return (1);
}
#define __set_bit(i, a) \
atomic_set_long(&((volatile long *)(a))[BIT_WORD(i)], BIT_MASK(i))
#define set_bit(i, a) \
atomic_set_long(&((volatile long *)(a))[BIT_WORD(i)], BIT_MASK(i))
#define __clear_bit(i, a) \
atomic_clear_long(&((volatile long *)(a))[BIT_WORD(i)], BIT_MASK(i))
#define clear_bit(i, a) \
atomic_clear_long(&((volatile long *)(a))[BIT_WORD(i)], BIT_MASK(i))
#define test_bit(i, a) \
!!(atomic_load_acq_long(&((volatile long *)(a))[BIT_WORD(i)]) & \
BIT_MASK(i))
static inline long
test_and_clear_bit(long bit, long *var)
{
long val;
var += BIT_WORD(bit);
bit %= BITS_PER_LONG;
bit = (1UL << 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;
var += BIT_WORD(bit);
bit %= BITS_PER_LONG;
bit = (1UL << bit);
do {
val = *(volatile long *)var;
} while (atomic_cmpset_long(var, val, val | bit) == 0);
return !!(val & bit);
}
static inline void
bitmap_set(unsigned long *map, int start, int nr)
{
unsigned long *p = map + BIT_WORD(start);
const int size = start + nr;
int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
while (nr - bits_to_set >= 0) {
*p |= mask_to_set;
nr -= bits_to_set;
bits_to_set = BITS_PER_LONG;
mask_to_set = ~0UL;
p++;
}
if (nr) {
mask_to_set &= BITMAP_LAST_WORD_MASK(size);
*p |= mask_to_set;
}
}
static inline void
bitmap_clear(unsigned long *map, int start, int nr)
{
unsigned long *p = map + BIT_WORD(start);
const int size = start + nr;
int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
while (nr - bits_to_clear >= 0) {
*p &= ~mask_to_clear;
nr -= bits_to_clear;
bits_to_clear = BITS_PER_LONG;
mask_to_clear = ~0UL;
p++;
}
if (nr) {
mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
*p &= ~mask_to_clear;
}
}
enum {
REG_OP_ISFREE,
REG_OP_ALLOC,
REG_OP_RELEASE,
};
static int __reg_op(unsigned long *bitmap, int pos, int order, int reg_op)
{
int nbits_reg;
int index;
int offset;
int nlongs_reg;
int nbitsinlong;
unsigned long mask;
int i;
int ret = 0;
nbits_reg = 1 << order;
index = pos / BITS_PER_LONG;
offset = pos - (index * BITS_PER_LONG);
nlongs_reg = BITS_TO_LONGS(nbits_reg);
nbitsinlong = min(nbits_reg, BITS_PER_LONG);
mask = (1UL << (nbitsinlong - 1));
mask += mask - 1;
mask <<= offset;
switch (reg_op) {
case REG_OP_ISFREE:
for (i = 0; i < nlongs_reg; i++) {
if (bitmap[index + i] & mask)
goto done;
}
ret = 1;
break;
case REG_OP_ALLOC:
for (i = 0; i < nlongs_reg; i++)
bitmap[index + i] |= mask;
break;
case REG_OP_RELEASE:
for (i = 0; i < nlongs_reg; i++)
bitmap[index + i] &= ~mask;
break;
}
done:
return ret;
}
static inline int
bitmap_find_free_region(unsigned long *bitmap, int bits, int order)
{
int pos;
int end;
for (pos = 0 ; (end = pos + (1 << order)) <= bits; pos = end) {
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
continue;
__reg_op(bitmap, pos, order, REG_OP_ALLOC);
return pos;
}
return -ENOMEM;
}
static inline int
bitmap_allocate_region(unsigned long *bitmap, int pos, int order)
{
if (!__reg_op(bitmap, pos, order, REG_OP_ISFREE))
return -EBUSY;
__reg_op(bitmap, pos, order, REG_OP_ALLOC);
return 0;
}
static inline void
bitmap_release_region(unsigned long *bitmap, int pos, int order)
{
__reg_op(bitmap, pos, order, REG_OP_RELEASE);
}
#define for_each_set_bit(bit, addr, size) \
for ((bit) = find_first_bit((addr), (size)); \
(bit) < (size); \
(bit) = find_next_bit((addr), (size), (bit) + 1))
static inline unsigned
bitmap_weight(unsigned long *bitmap, unsigned nbits)
{
unsigned bit;
unsigned retval = 0;
for_each_set_bit(bit, bitmap, nbits)
retval++;
return (retval);
}
static inline int
bitmap_equal(const unsigned long *pa,
const unsigned long *pb, unsigned bits)
{
unsigned x;
unsigned y = bits / BITS_PER_LONG;
for (x = 0; x != y; x++) {
if (pa[x] != pb[x])
return (0);
}
y = bits % BITS_PER_LONG;
if (y != 0) {
if ((pa[x] ^ pb[x]) & BITMAP_LAST_WORD_MASK(y))
return (0);
}
return (1);
}
#endif /* _LINUX_BITOPS_H_ */