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/*
* 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 for an
* s390x system the bits end up numbered:
* |63..............0|127............64|191...........128|255...........196|
* and on s390:
* |31.....0|63....31|95....64|127...96|159..128|191..160|223..192|255..224|
*
* 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 (64b) or 3-4 (32b) in the bit
* number field needs to be reversed compared to the big-endian bit
* fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b).
*
* We also have special functions which work with an MSB0 encoding:
* on an s390x system the bits are numbered:
* |0..............63|64............127|128...........191|192...........255|
* and on s390:
* |0.....31|31....63|64....95|96...127|128..159|160..191|192..223|224..255|
*
* The main difference is that bit 0-63 (64b) or 0-31 (32b) in the bit
* number field needs to be reversed compared to the LSB0 encoded bit
* fields. This can be achieved by XOR with 0x3f (64b) or 0x1f (32b).
*
*/
#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 <asm/barrier.h>
#define __BITOPS_NO_BARRIER "\n"
#ifndef CONFIG_64BIT
#define __BITOPS_OR "or"
#define __BITOPS_AND "nr"
#define __BITOPS_XOR "xr"
#define __BITOPS_BARRIER "\n"
#define __BITOPS_LOOP(__addr, __val, __op_string, __barrier) \
({ \
unsigned long __old, __new; \
\
typecheck(unsigned long *, (__addr)); \
asm volatile( \
" l %0,%2\n" \
"0: lr %1,%0\n" \
__op_string " %1,%3\n" \
" cs %0,%1,%2\n" \
" jl 0b" \
: "=&d" (__old), "=&d" (__new), "+Q" (*(__addr))\
: "d" (__val) \
: "cc", "memory"); \
__old; \
})
#else /* CONFIG_64BIT */
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
#define __BITOPS_OR "laog"
#define __BITOPS_AND "lang"
#define __BITOPS_XOR "laxg"
#define __BITOPS_BARRIER "bcr 14,0\n"
#define __BITOPS_LOOP(__addr, __val, __op_string, __barrier) \
({ \
unsigned long __old; \
\
typecheck(unsigned long *, (__addr)); \
asm volatile( \
__barrier \
__op_string " %0,%2,%1\n" \
__barrier \
: "=d" (__old), "+Q" (*(__addr)) \
: "d" (__val) \
: "cc", "memory"); \
__old; \
})
#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
#define __BITOPS_OR "ogr"
#define __BITOPS_AND "ngr"
#define __BITOPS_XOR "xgr"
#define __BITOPS_BARRIER "\n"
#define __BITOPS_LOOP(__addr, __val, __op_string, __barrier) \
({ \
unsigned long __old, __new; \
\
typecheck(unsigned long *, (__addr)); \
asm volatile( \
" lg %0,%2\n" \
"0: lgr %1,%0\n" \
__op_string " %1,%3\n" \
" csg %0,%1,%2\n" \
" jl 0b" \
: "=&d" (__old), "=&d" (__new), "+Q" (*(__addr))\
: "d" (__val) \
: "cc", "memory"); \
__old; \
})
#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
#endif /* CONFIG_64BIT */
#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 inline void 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));
__BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_NO_BARRIER);
}
static inline void 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)));
__BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_NO_BARRIER);
}
static inline void 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));
__BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_NO_BARRIER);
}
static inline int
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 = __BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_BARRIER);
return (old & mask) != 0;
}
static inline int
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 = __BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_BARRIER);
return (old & ~mask) != 0;
}
static inline int
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 = __BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_BARRIER);
return (old & mask) != 0;
}
static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
*addr |= 1 << (nr & 7);
}
static inline void
__clear_bit(unsigned long nr, volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
*addr &= ~(1 << (nr & 7));
}
static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
{
unsigned char *addr = __bitops_byte(nr, ptr);
*addr ^= 1 << (nr & 7);
}
static inline int
__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 int
__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 int
__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 int 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;
}
/*
* Functions which use MSB0 bit numbering.
* On an s390x system the bits are numbered:
* |0..............63|64............127|128...........191|192...........255|
* and on s390:
* |0.....31|31....63|64....95|96...127|128..159|160..191|192..223|224..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);
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 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 int 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(int word)
{
return fls64((unsigned int)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/lock.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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