1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright IBM Corp. 1999,2013
5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
7 * The description below was taken in large parts from the powerpc
9 * Within a word, bits are numbered LSB first. Lot's of places make
10 * this assumption by directly testing bits with (val & (1<<nr)).
11 * This can cause confusion for large (> 1 word) bitmaps on a
12 * big-endian system because, unlike little endian, the number of each
13 * bit depends on the word size.
15 * The bitop functions are defined to work on unsigned longs, so the bits
17 * |63..............0|127............64|191...........128|255...........192|
19 * We also have special functions which work with an MSB0 encoding.
20 * The bits are numbered:
21 * |0..............63|64............127|128...........191|192...........255|
23 * The main difference is that bit 0-63 in the bit number field needs to be
24 * reversed compared to the LSB0 encoded bit fields. This can be achieved by
29 #ifndef _S390_BITOPS_H
30 #define _S390_BITOPS_H
32 #ifndef _LINUX_BITOPS_H
33 #error only <linux/bitops.h> can be included directly
36 #include <linux/typecheck.h>
37 #include <linux/compiler.h>
38 #include <asm/atomic_ops.h>
39 #include <asm/barrier.h>
41 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
43 static inline unsigned long *
44 __bitops_word(unsigned long nr, volatile unsigned long *ptr)
48 addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3);
49 return (unsigned long *)addr;
52 static inline unsigned char *
53 __bitops_byte(unsigned long nr, volatile unsigned long *ptr)
55 return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3);
58 static inline void set_bit(unsigned long nr, volatile unsigned long *ptr)
60 unsigned long *addr = __bitops_word(nr, ptr);
63 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
64 if (__builtin_constant_p(nr)) {
65 unsigned char *caddr = __bitops_byte(nr, ptr);
75 mask = 1UL << (nr & (BITS_PER_LONG - 1));
76 __atomic64_or(mask, addr);
79 static inline void clear_bit(unsigned long nr, volatile unsigned long *ptr)
81 unsigned long *addr = __bitops_word(nr, ptr);
84 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
85 if (__builtin_constant_p(nr)) {
86 unsigned char *caddr = __bitops_byte(nr, ptr);
91 : "i" (~(1 << (nr & 7)))
96 mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
97 __atomic64_and(mask, addr);
100 static inline void change_bit(unsigned long nr, volatile unsigned long *ptr)
102 unsigned long *addr = __bitops_word(nr, ptr);
105 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
106 if (__builtin_constant_p(nr)) {
107 unsigned char *caddr = __bitops_byte(nr, ptr);
112 : "i" (1 << (nr & 7))
117 mask = 1UL << (nr & (BITS_PER_LONG - 1));
118 __atomic64_xor(mask, addr);
122 test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
124 unsigned long *addr = __bitops_word(nr, ptr);
125 unsigned long old, mask;
127 mask = 1UL << (nr & (BITS_PER_LONG - 1));
128 old = __atomic64_or_barrier(mask, addr);
129 return (old & mask) != 0;
133 test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
135 unsigned long *addr = __bitops_word(nr, ptr);
136 unsigned long old, mask;
138 mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
139 old = __atomic64_and_barrier(mask, addr);
140 return (old & ~mask) != 0;
144 test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
146 unsigned long *addr = __bitops_word(nr, ptr);
147 unsigned long old, mask;
149 mask = 1UL << (nr & (BITS_PER_LONG - 1));
150 old = __atomic64_xor_barrier(mask, addr);
151 return (old & mask) != 0;
154 static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
156 unsigned char *addr = __bitops_byte(nr, ptr);
158 *addr |= 1 << (nr & 7);
162 __clear_bit(unsigned long nr, volatile unsigned long *ptr)
164 unsigned char *addr = __bitops_byte(nr, ptr);
166 *addr &= ~(1 << (nr & 7));
169 static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
171 unsigned char *addr = __bitops_byte(nr, ptr);
173 *addr ^= 1 << (nr & 7);
177 __test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
179 unsigned char *addr = __bitops_byte(nr, ptr);
183 *addr |= 1 << (nr & 7);
184 return (ch >> (nr & 7)) & 1;
188 __test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
190 unsigned char *addr = __bitops_byte(nr, ptr);
194 *addr &= ~(1 << (nr & 7));
195 return (ch >> (nr & 7)) & 1;
199 __test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
201 unsigned char *addr = __bitops_byte(nr, ptr);
205 *addr ^= 1 << (nr & 7);
206 return (ch >> (nr & 7)) & 1;
209 static inline int test_bit(unsigned long nr, const volatile unsigned long *ptr)
211 const volatile unsigned char *addr;
213 addr = ((const volatile unsigned char *)ptr);
214 addr += (nr ^ (BITS_PER_LONG - 8)) >> 3;
215 return (*addr >> (nr & 7)) & 1;
218 static inline int test_and_set_bit_lock(unsigned long nr,
219 volatile unsigned long *ptr)
221 if (test_bit(nr, ptr))
223 return test_and_set_bit(nr, ptr);
226 static inline void clear_bit_unlock(unsigned long nr,
227 volatile unsigned long *ptr)
229 smp_mb__before_atomic();
233 static inline void __clear_bit_unlock(unsigned long nr,
234 volatile unsigned long *ptr)
237 __clear_bit(nr, ptr);
241 * Functions which use MSB0 bit numbering.
242 * The bits are numbered:
243 * |0..............63|64............127|128...........191|192...........255|
245 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size);
246 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
247 unsigned long offset);
249 #define for_each_set_bit_inv(bit, addr, size) \
250 for ((bit) = find_first_bit_inv((addr), (size)); \
252 (bit) = find_next_bit_inv((addr), (size), (bit) + 1))
254 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
256 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
259 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
261 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
264 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
266 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
269 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
271 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
274 static inline int test_bit_inv(unsigned long nr,
275 const volatile unsigned long *ptr)
277 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);
280 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
283 * __flogr - find leftmost one
284 * @word - The word to search
286 * Returns the bit number of the most significant bit set,
287 * where the most significant bit has bit number 0.
288 * If no bit is set this function returns 64.
290 static inline unsigned char __flogr(unsigned long word)
292 if (__builtin_constant_p(word)) {
293 unsigned long bit = 0;
297 if (!(word & 0xffffffff00000000UL)) {
301 if (!(word & 0xffff000000000000UL)) {
305 if (!(word & 0xff00000000000000UL)) {
309 if (!(word & 0xf000000000000000UL)) {
313 if (!(word & 0xc000000000000000UL)) {
317 if (!(word & 0x8000000000000000UL)) {
323 register unsigned long bit asm("4") = word;
324 register unsigned long out asm("5");
327 " flogr %[bit],%[bit]\n"
328 : [bit] "+d" (bit), [out] "=d" (out) : : "cc");
334 * __ffs - find first bit in word.
335 * @word: The word to search
337 * Undefined if no bit exists, so code should check against 0 first.
339 static inline unsigned long __ffs(unsigned long word)
341 return __flogr(-word & word) ^ (BITS_PER_LONG - 1);
345 * ffs - find first bit set
346 * @word: the word to search
348 * This is defined the same way as the libc and
349 * compiler builtin ffs routines (man ffs).
351 static inline int ffs(int word)
353 unsigned long mask = 2 * BITS_PER_LONG - 1;
354 unsigned int val = (unsigned int)word;
356 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask;
360 * __fls - find last (most-significant) set bit in a long word
361 * @word: the word to search
363 * Undefined if no set bit exists, so code should check against 0 first.
365 static inline unsigned long __fls(unsigned long word)
367 return __flogr(word) ^ (BITS_PER_LONG - 1);
371 * fls64 - find last set bit in a 64-bit word
372 * @word: the word to search
374 * This is defined in a similar way as the libc and compiler builtin
375 * ffsll, but returns the position of the most significant set bit.
377 * fls64(value) returns 0 if value is 0 or the position of the last
378 * set bit if value is nonzero. The last (most significant) bit is
381 static inline int fls64(unsigned long word)
383 unsigned long mask = 2 * BITS_PER_LONG - 1;
385 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask;
389 * fls - find last (most-significant) bit set
390 * @word: the word to search
392 * This is defined the same way as ffs.
393 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
395 static inline int fls(int word)
397 return fls64((unsigned int)word);
400 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
402 #include <asm-generic/bitops/__ffs.h>
403 #include <asm-generic/bitops/ffs.h>
404 #include <asm-generic/bitops/__fls.h>
405 #include <asm-generic/bitops/fls.h>
406 #include <asm-generic/bitops/fls64.h>
408 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
410 #include <asm-generic/bitops/ffz.h>
411 #include <asm-generic/bitops/find.h>
412 #include <asm-generic/bitops/hweight.h>
413 #include <asm-generic/bitops/sched.h>
414 #include <asm-generic/bitops/le.h>
415 #include <asm-generic/bitops/ext2-atomic-setbit.h>
417 #endif /* _S390_BITOPS_H */