1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright IBM Corp. 1999,2013
4 *
5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
6 *
7 * The description below was taken in large parts from the powerpc
8 * bitops header file:
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.
14 *
15 * The bitop functions are defined to work on unsigned longs, so the bits
16 * end up numbered:
17 * |63..............0|127............64|191...........128|255...........192|
18 *
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|
22 *
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
25 * XOR with 0x3f.
26 *
27 */
28
29 #ifndef _S390_BITOPS_H
30 #define _S390_BITOPS_H
31
32 #ifndef _LINUX_BITOPS_H
33 #error only <linux/bitops.h> can be included directly
34 #endif
35
36 #include <linux/typecheck.h>
37 #include <linux/compiler.h>
38 #include <linux/types.h>
39 #include <asm/atomic_ops.h>
40 #include <asm/barrier.h>
41
42 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
43
44 static inline unsigned long *
__bitops_word(unsigned long nr,const volatile unsigned long * ptr)45 __bitops_word(unsigned long nr, const volatile unsigned long *ptr)
46 {
47 unsigned long addr;
48
49 addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3);
50 return (unsigned long *)addr;
51 }
52
__bitops_mask(unsigned long nr)53 static inline unsigned long __bitops_mask(unsigned long nr)
54 {
55 return 1UL << (nr & (BITS_PER_LONG - 1));
56 }
57
arch_set_bit(unsigned long nr,volatile unsigned long * ptr)58 static __always_inline void arch_set_bit(unsigned long nr, volatile unsigned long *ptr)
59 {
60 unsigned long *addr = __bitops_word(nr, ptr);
61 unsigned long mask = __bitops_mask(nr);
62
63 __atomic64_or(mask, (long *)addr);
64 }
65
arch_clear_bit(unsigned long nr,volatile unsigned long * ptr)66 static __always_inline void arch_clear_bit(unsigned long nr, volatile unsigned long *ptr)
67 {
68 unsigned long *addr = __bitops_word(nr, ptr);
69 unsigned long mask = __bitops_mask(nr);
70
71 __atomic64_and(~mask, (long *)addr);
72 }
73
arch_change_bit(unsigned long nr,volatile unsigned long * ptr)74 static __always_inline void arch_change_bit(unsigned long nr,
75 volatile unsigned long *ptr)
76 {
77 unsigned long *addr = __bitops_word(nr, ptr);
78 unsigned long mask = __bitops_mask(nr);
79
80 __atomic64_xor(mask, (long *)addr);
81 }
82
arch_test_and_set_bit(unsigned long nr,volatile unsigned long * ptr)83 static inline bool arch_test_and_set_bit(unsigned long nr,
84 volatile unsigned long *ptr)
85 {
86 unsigned long *addr = __bitops_word(nr, ptr);
87 unsigned long mask = __bitops_mask(nr);
88 unsigned long old;
89
90 old = __atomic64_or_barrier(mask, (long *)addr);
91 return old & mask;
92 }
93
arch_test_and_clear_bit(unsigned long nr,volatile unsigned long * ptr)94 static inline bool arch_test_and_clear_bit(unsigned long nr,
95 volatile unsigned long *ptr)
96 {
97 unsigned long *addr = __bitops_word(nr, ptr);
98 unsigned long mask = __bitops_mask(nr);
99 unsigned long old;
100
101 old = __atomic64_and_barrier(~mask, (long *)addr);
102 return old & mask;
103 }
104
arch_test_and_change_bit(unsigned long nr,volatile unsigned long * ptr)105 static inline bool arch_test_and_change_bit(unsigned long nr,
106 volatile unsigned long *ptr)
107 {
108 unsigned long *addr = __bitops_word(nr, ptr);
109 unsigned long mask = __bitops_mask(nr);
110 unsigned long old;
111
112 old = __atomic64_xor_barrier(mask, (long *)addr);
113 return old & mask;
114 }
115
arch___set_bit(unsigned long nr,volatile unsigned long * ptr)116 static inline void arch___set_bit(unsigned long nr, volatile unsigned long *ptr)
117 {
118 unsigned long *addr = __bitops_word(nr, ptr);
119 unsigned long mask = __bitops_mask(nr);
120
121 *addr |= mask;
122 }
123
arch___clear_bit(unsigned long nr,volatile unsigned long * ptr)124 static inline void arch___clear_bit(unsigned long nr,
125 volatile unsigned long *ptr)
126 {
127 unsigned long *addr = __bitops_word(nr, ptr);
128 unsigned long mask = __bitops_mask(nr);
129
130 *addr &= ~mask;
131 }
132
arch___change_bit(unsigned long nr,volatile unsigned long * ptr)133 static inline void arch___change_bit(unsigned long nr,
134 volatile unsigned long *ptr)
135 {
136 unsigned long *addr = __bitops_word(nr, ptr);
137 unsigned long mask = __bitops_mask(nr);
138
139 *addr ^= mask;
140 }
141
arch___test_and_set_bit(unsigned long nr,volatile unsigned long * ptr)142 static inline bool arch___test_and_set_bit(unsigned long nr,
143 volatile unsigned long *ptr)
144 {
145 unsigned long *addr = __bitops_word(nr, ptr);
146 unsigned long mask = __bitops_mask(nr);
147 unsigned long old;
148
149 old = *addr;
150 *addr |= mask;
151 return old & mask;
152 }
153
arch___test_and_clear_bit(unsigned long nr,volatile unsigned long * ptr)154 static inline bool arch___test_and_clear_bit(unsigned long nr,
155 volatile unsigned long *ptr)
156 {
157 unsigned long *addr = __bitops_word(nr, ptr);
158 unsigned long mask = __bitops_mask(nr);
159 unsigned long old;
160
161 old = *addr;
162 *addr &= ~mask;
163 return old & mask;
164 }
165
arch___test_and_change_bit(unsigned long nr,volatile unsigned long * ptr)166 static inline bool arch___test_and_change_bit(unsigned long nr,
167 volatile unsigned long *ptr)
168 {
169 unsigned long *addr = __bitops_word(nr, ptr);
170 unsigned long mask = __bitops_mask(nr);
171 unsigned long old;
172
173 old = *addr;
174 *addr ^= mask;
175 return old & mask;
176 }
177
arch_test_bit(unsigned long nr,const volatile unsigned long * ptr)178 static inline bool arch_test_bit(unsigned long nr,
179 const volatile unsigned long *ptr)
180 {
181 const volatile unsigned long *addr = __bitops_word(nr, ptr);
182 unsigned long mask = __bitops_mask(nr);
183
184 return *addr & mask;
185 }
186
arch_test_and_set_bit_lock(unsigned long nr,volatile unsigned long * ptr)187 static inline bool arch_test_and_set_bit_lock(unsigned long nr,
188 volatile unsigned long *ptr)
189 {
190 if (arch_test_bit(nr, ptr))
191 return 1;
192 return arch_test_and_set_bit(nr, ptr);
193 }
194
arch_clear_bit_unlock(unsigned long nr,volatile unsigned long * ptr)195 static inline void arch_clear_bit_unlock(unsigned long nr,
196 volatile unsigned long *ptr)
197 {
198 smp_mb__before_atomic();
199 arch_clear_bit(nr, ptr);
200 }
201
arch___clear_bit_unlock(unsigned long nr,volatile unsigned long * ptr)202 static inline void arch___clear_bit_unlock(unsigned long nr,
203 volatile unsigned long *ptr)
204 {
205 smp_mb();
206 arch___clear_bit(nr, ptr);
207 }
208
209 #include <asm-generic/bitops/instrumented-atomic.h>
210 #include <asm-generic/bitops/instrumented-non-atomic.h>
211 #include <asm-generic/bitops/instrumented-lock.h>
212
213 /*
214 * Functions which use MSB0 bit numbering.
215 * The bits are numbered:
216 * |0..............63|64............127|128...........191|192...........255|
217 */
218 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size);
219 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
220 unsigned long offset);
221
222 #define for_each_set_bit_inv(bit, addr, size) \
223 for ((bit) = find_first_bit_inv((addr), (size)); \
224 (bit) < (size); \
225 (bit) = find_next_bit_inv((addr), (size), (bit) + 1))
226
set_bit_inv(unsigned long nr,volatile unsigned long * ptr)227 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
228 {
229 return set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
230 }
231
clear_bit_inv(unsigned long nr,volatile unsigned long * ptr)232 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
233 {
234 return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
235 }
236
test_and_clear_bit_inv(unsigned long nr,volatile unsigned long * ptr)237 static inline bool test_and_clear_bit_inv(unsigned long nr,
238 volatile unsigned long *ptr)
239 {
240 return test_and_clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
241 }
242
__set_bit_inv(unsigned long nr,volatile unsigned long * ptr)243 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
244 {
245 return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
246 }
247
__clear_bit_inv(unsigned long nr,volatile unsigned long * ptr)248 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
249 {
250 return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
251 }
252
test_bit_inv(unsigned long nr,const volatile unsigned long * ptr)253 static inline bool test_bit_inv(unsigned long nr,
254 const volatile unsigned long *ptr)
255 {
256 return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);
257 }
258
259 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
260
261 /**
262 * __flogr - find leftmost one
263 * @word - The word to search
264 *
265 * Returns the bit number of the most significant bit set,
266 * where the most significant bit has bit number 0.
267 * If no bit is set this function returns 64.
268 */
__flogr(unsigned long word)269 static inline unsigned char __flogr(unsigned long word)
270 {
271 if (__builtin_constant_p(word)) {
272 unsigned long bit = 0;
273
274 if (!word)
275 return 64;
276 if (!(word & 0xffffffff00000000UL)) {
277 word <<= 32;
278 bit += 32;
279 }
280 if (!(word & 0xffff000000000000UL)) {
281 word <<= 16;
282 bit += 16;
283 }
284 if (!(word & 0xff00000000000000UL)) {
285 word <<= 8;
286 bit += 8;
287 }
288 if (!(word & 0xf000000000000000UL)) {
289 word <<= 4;
290 bit += 4;
291 }
292 if (!(word & 0xc000000000000000UL)) {
293 word <<= 2;
294 bit += 2;
295 }
296 if (!(word & 0x8000000000000000UL)) {
297 word <<= 1;
298 bit += 1;
299 }
300 return bit;
301 } else {
302 union register_pair rp;
303
304 rp.even = word;
305 asm volatile(
306 " flogr %[rp],%[rp]\n"
307 : [rp] "+d" (rp.pair) : : "cc");
308 return rp.even;
309 }
310 }
311
312 /**
313 * __ffs - find first bit in word.
314 * @word: The word to search
315 *
316 * Undefined if no bit exists, so code should check against 0 first.
317 */
__ffs(unsigned long word)318 static inline unsigned long __ffs(unsigned long word)
319 {
320 return __flogr(-word & word) ^ (BITS_PER_LONG - 1);
321 }
322
323 /**
324 * ffs - find first bit set
325 * @word: the word to search
326 *
327 * This is defined the same way as the libc and
328 * compiler builtin ffs routines (man ffs).
329 */
ffs(int word)330 static inline int ffs(int word)
331 {
332 unsigned long mask = 2 * BITS_PER_LONG - 1;
333 unsigned int val = (unsigned int)word;
334
335 return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask;
336 }
337
338 /**
339 * __fls - find last (most-significant) set bit in a long word
340 * @word: the word to search
341 *
342 * Undefined if no set bit exists, so code should check against 0 first.
343 */
__fls(unsigned long word)344 static inline unsigned long __fls(unsigned long word)
345 {
346 return __flogr(word) ^ (BITS_PER_LONG - 1);
347 }
348
349 /**
350 * fls64 - find last set bit in a 64-bit word
351 * @word: the word to search
352 *
353 * This is defined in a similar way as the libc and compiler builtin
354 * ffsll, but returns the position of the most significant set bit.
355 *
356 * fls64(value) returns 0 if value is 0 or the position of the last
357 * set bit if value is nonzero. The last (most significant) bit is
358 * at position 64.
359 */
fls64(unsigned long word)360 static inline int fls64(unsigned long word)
361 {
362 unsigned long mask = 2 * BITS_PER_LONG - 1;
363
364 return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask;
365 }
366
367 /**
368 * fls - find last (most-significant) bit set
369 * @word: the word to search
370 *
371 * This is defined the same way as ffs.
372 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
373 */
fls(unsigned int word)374 static inline int fls(unsigned int word)
375 {
376 return fls64(word);
377 }
378
379 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
380
381 #include <asm-generic/bitops/__ffs.h>
382 #include <asm-generic/bitops/ffs.h>
383 #include <asm-generic/bitops/__fls.h>
384 #include <asm-generic/bitops/fls.h>
385 #include <asm-generic/bitops/fls64.h>
386
387 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
388
389 #include <asm-generic/bitops/ffz.h>
390 #include <asm-generic/bitops/find.h>
391 #include <asm-generic/bitops/hweight.h>
392 #include <asm-generic/bitops/sched.h>
393 #include <asm-generic/bitops/le.h>
394 #include <asm-generic/bitops/ext2-atomic-setbit.h>
395
396 #endif /* _S390_BITOPS_H */
397