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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright IBM Corp. 1999,2013
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
*
* The description below was taken in large parts from the powerpc
* bitops header file:
* Within a word, bits are numbered LSB first. Lot's of places make
* this assumption by directly testing bits with (val & (1<<nr)).
* This can cause confusion for large (> 1 word) bitmaps on a
* big-endian system because, unlike little endian, the number of each
* bit depends on the word size.
*
* The bitop functions are defined to work on unsigned longs, so the bits
* end up numbered:
* |63..............0|127............64|191...........128|255...........192|
*
* We also have special functions which work with an MSB0 encoding.
* The bits are numbered:
* |0..............63|64............127|128...........191|192...........255|
*
* The main difference is that bit 0-63 in the bit number field needs to be
* reversed compared to the LSB0 encoded bit fields. This can be achieved by
* XOR with 0x3f.
*
*/
#ifndef _S390_BITOPS_H
#define _S390_BITOPS_H
#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif
#include <linux/typecheck.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/atomic_ops.h>
#include <asm/barrier.h>
#define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
static inline unsigned long *
__bitops_word(unsigned long nr, volatile unsigned long *ptr)
{
unsigned long addr;
addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3);
return (unsigned long *)addr;
}
static inline unsigned char *
__bitops_byte(unsigned long nr, volatile unsigned long *ptr)
{
return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3);
}
static __always_inline void arch_set_bit(unsigned long nr, volatile unsigned long *ptr)
{
unsigned long *addr = __bitops_word(nr, ptr);
unsigned long mask;
#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
if (__builtin_constant_p(nr)) {
unsigned char *caddr = __bitops_byte(nr, ptr);
asm volatile(
"oi %0,%b1\n"
: "+Q" (*caddr)
: "i" (1 << (nr & 7))
: "cc", "memory");
return;
}
#endif
mask = 1UL << (nr & (BITS_PER_LONG - 1));
__atomic64_or(mask, (long *)addr);
}
static __always_inline void arch_clear_bit(unsigned long nr, volatile unsigned long *ptr)
{
unsigned long *addr = __bitops_word(nr, ptr);
unsigned long mask;
#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
if (__builtin_constant_p(nr)) {
unsigned char *caddr = __bitops_byte(nr, ptr);
asm volatile(
"ni %0,%b1\n"
: "+Q" (*caddr)
: "i" (~(1 << (nr & 7)))
: "cc", "memory");
return;
}
#endif
mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
__atomic64_and(mask, (long *)addr);
}
static __always_inline void arch_change_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned long *addr = __bitops_word(nr, ptr);
unsigned long mask;
#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
if (__builtin_constant_p(nr)) {
unsigned char *caddr = __bitops_byte(nr, ptr);
asm volatile(
"xi %0,%b1\n"
: "+Q" (*caddr)
: "i" (1 << (nr & 7))
: "cc", "memory");
return;
}
#endif
mask = 1UL << (nr & (BITS_PER_LONG - 1));
__atomic64_xor(mask, (long *)addr);
}
static inline bool arch_test_and_set_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned long *addr = __bitops_word(nr, ptr);
unsigned long old, mask;
mask = 1UL << (nr & (BITS_PER_LONG - 1));
old = __atomic64_or_barrier(mask, (long *)addr);
return (old & mask) != 0;
}
static inline bool arch_test_and_clear_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned long *addr = __bitops_word(nr, ptr);
unsigned long old, mask;
mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
old = __atomic64_and_barrier(mask, (long *)addr);
return (old & ~mask) != 0;
}
static inline bool arch_test_and_change_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned long *addr = __bitops_word(nr, ptr);
unsigned long old, mask;
mask = 1UL << (nr & (BITS_PER_LONG - 1));
old = __atomic64_xor_barrier(mask, (long *)addr);
return (old & mask) != 0;
}
static inline void arch___set_bit(unsigned long nr, volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
*addr |= 1 << (nr & 7);
}
static inline void arch___clear_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
*addr &= ~(1 << (nr & 7));
}
static inline void arch___change_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
*addr ^= 1 << (nr & 7);
}
static inline bool arch___test_and_set_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
unsigned char ch;
ch = *addr;
*addr |= 1 << (nr & 7);
return (ch >> (nr & 7)) & 1;
}
static inline bool arch___test_and_clear_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
unsigned char ch;
ch = *addr;
*addr &= ~(1 << (nr & 7));
return (ch >> (nr & 7)) & 1;
}
static inline bool arch___test_and_change_bit(unsigned long nr,
volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
unsigned char ch;
ch = *addr;
*addr ^= 1 << (nr & 7);
return (ch >> (nr & 7)) & 1;
}
static inline bool arch_test_bit(unsigned long nr,
const volatile unsigned long *ptr)
{
const volatile unsigned char *addr;
addr = ((const volatile unsigned char *)ptr);
addr += (nr ^ (BITS_PER_LONG - 8)) >> 3;
return (*addr >> (nr & 7)) & 1;
}
static inline bool arch_test_and_set_bit_lock(unsigned long nr,
volatile unsigned long *ptr)
{
if (arch_test_bit(nr, ptr))
return 1;
return arch_test_and_set_bit(nr, ptr);
}
static inline void arch_clear_bit_unlock(unsigned long nr,
volatile unsigned long *ptr)
{
smp_mb__before_atomic();
arch_clear_bit(nr, ptr);
}
static inline void arch___clear_bit_unlock(unsigned long nr,
volatile unsigned long *ptr)
{
smp_mb();
arch___clear_bit(nr, ptr);
}
#include <asm-generic/bitops-instrumented.h>
/*
* Functions which use MSB0 bit numbering.
* The bits are numbered:
* |0..............63|64............127|128...........191|192...........255|
*/
unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size);
unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
unsigned long offset);
#define for_each_set_bit_inv(bit, addr, size) \
for ((bit) = find_first_bit_inv((addr), (size)); \
(bit) < (size); \
(bit) = find_next_bit_inv((addr), (size), (bit) + 1))
static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
{
return set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
}
static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
{
return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
}
static inline bool test_and_clear_bit_inv(unsigned long nr,
volatile unsigned long *ptr)
{
return test_and_clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
}
static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
{
return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
}
static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
{
return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
}
static inline bool test_bit_inv(unsigned long nr,
const volatile unsigned long *ptr)
{
return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);
}
#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
/**
* __flogr - find leftmost one
* @word - The word to search
*
* Returns the bit number of the most significant bit set,
* where the most significant bit has bit number 0.
* If no bit is set this function returns 64.
*/
static inline unsigned char __flogr(unsigned long word)
{
if (__builtin_constant_p(word)) {
unsigned long bit = 0;
if (!word)
return 64;
if (!(word & 0xffffffff00000000UL)) {
word <<= 32;
bit += 32;
}
if (!(word & 0xffff000000000000UL)) {
word <<= 16;
bit += 16;
}
if (!(word & 0xff00000000000000UL)) {
word <<= 8;
bit += 8;
}
if (!(word & 0xf000000000000000UL)) {
word <<= 4;
bit += 4;
}
if (!(word & 0xc000000000000000UL)) {
word <<= 2;
bit += 2;
}
if (!(word & 0x8000000000000000UL)) {
word <<= 1;
bit += 1;
}
return bit;
} else {
register unsigned long bit asm("4") = word;
register unsigned long out asm("5");
asm volatile(
" flogr %[bit],%[bit]\n"
: [bit] "+d" (bit), [out] "=d" (out) : : "cc");
return bit;
}
}
/**
* __ffs - find first bit in word.
* @word: The word to search
*
* Undefined if no bit exists, so code should check against 0 first.
*/
static inline unsigned long __ffs(unsigned long word)
{
return __flogr(-word & word) ^ (BITS_PER_LONG - 1);
}
/**
* ffs - find first bit set
* @word: the word to search
*
* This is defined the same way as the libc and
* compiler builtin ffs routines (man ffs).
*/
static inline int ffs(int word)
{
unsigned long mask = 2 * BITS_PER_LONG - 1;
unsigned int val = (unsigned int)word;
return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask;
}
/**
* __fls - find last (most-significant) set bit in a long word
* @word: the word to search
*
* Undefined if no set bit exists, so code should check against 0 first.
*/
static inline unsigned long __fls(unsigned long word)
{
return __flogr(word) ^ (BITS_PER_LONG - 1);
}
/**
* fls64 - find last set bit in a 64-bit word
* @word: the word to search
*
* This is defined in a similar way as the libc and compiler builtin
* ffsll, but returns the position of the most significant set bit.
*
* fls64(value) returns 0 if value is 0 or the position of the last
* set bit if value is nonzero. The last (most significant) bit is
* at position 64.
*/
static inline int fls64(unsigned long word)
{
unsigned long mask = 2 * BITS_PER_LONG - 1;
return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask;
}
/**
* fls - find last (most-significant) bit set
* @word: the word to search
*
* This is defined the same way as ffs.
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
*/
static inline int fls(unsigned int word)
{
return fls64(word);
}
#else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/ffs.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/fls64.h>
#endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/find.h>
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/sched.h>
#include <asm-generic/bitops/le.h>
#include <asm-generic/bitops/ext2-atomic-setbit.h>
#endif /* _S390_BITOPS_H */
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