xref: /linux/arch/s390/include/asm/bitops.h (revision ce7240e445303de3ca66e6d08f17a2ec278a5bf6)
1 #ifndef _S390_BITOPS_H
2 #define _S390_BITOPS_H
3 
4 /*
5  *  include/asm-s390/bitops.h
6  *
7  *  S390 version
8  *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
9  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
10  *
11  *  Derived from "include/asm-i386/bitops.h"
12  *    Copyright (C) 1992, Linus Torvalds
13  *
14  */
15 
16 #ifndef _LINUX_BITOPS_H
17 #error only <linux/bitops.h> can be included directly
18 #endif
19 
20 #include <linux/compiler.h>
21 
22 /*
23  * 32 bit bitops format:
24  * bit 0 is the LSB of *addr; bit 31 is the MSB of *addr;
25  * bit 32 is the LSB of *(addr+4). That combined with the
26  * big endian byte order on S390 give the following bit
27  * order in memory:
28  *    1f 1e 1d 1c 1b 1a 19 18 17 16 15 14 13 12 11 10 \
29  *    0f 0e 0d 0c 0b 0a 09 08 07 06 05 04 03 02 01 00
30  * after that follows the next long with bit numbers
31  *    3f 3e 3d 3c 3b 3a 39 38 37 36 35 34 33 32 31 30
32  *    2f 2e 2d 2c 2b 2a 29 28 27 26 25 24 23 22 21 20
33  * The reason for this bit ordering is the fact that
34  * in the architecture independent code bits operations
35  * of the form "flags |= (1 << bitnr)" are used INTERMIXED
36  * with operation of the form "set_bit(bitnr, flags)".
37  *
38  * 64 bit bitops format:
39  * bit 0 is the LSB of *addr; bit 63 is the MSB of *addr;
40  * bit 64 is the LSB of *(addr+8). That combined with the
41  * big endian byte order on S390 give the following bit
42  * order in memory:
43  *    3f 3e 3d 3c 3b 3a 39 38 37 36 35 34 33 32 31 30
44  *    2f 2e 2d 2c 2b 2a 29 28 27 26 25 24 23 22 21 20
45  *    1f 1e 1d 1c 1b 1a 19 18 17 16 15 14 13 12 11 10
46  *    0f 0e 0d 0c 0b 0a 09 08 07 06 05 04 03 02 01 00
47  * after that follows the next long with bit numbers
48  *    7f 7e 7d 7c 7b 7a 79 78 77 76 75 74 73 72 71 70
49  *    6f 6e 6d 6c 6b 6a 69 68 67 66 65 64 63 62 61 60
50  *    5f 5e 5d 5c 5b 5a 59 58 57 56 55 54 53 52 51 50
51  *    4f 4e 4d 4c 4b 4a 49 48 47 46 45 44 43 42 41 40
52  * The reason for this bit ordering is the fact that
53  * in the architecture independent code bits operations
54  * of the form "flags |= (1 << bitnr)" are used INTERMIXED
55  * with operation of the form "set_bit(bitnr, flags)".
56  */
57 
58 /* bitmap tables from arch/s390/kernel/bitmap.c */
59 extern const char _oi_bitmap[];
60 extern const char _ni_bitmap[];
61 extern const char _zb_findmap[];
62 extern const char _sb_findmap[];
63 
64 #ifndef CONFIG_64BIT
65 
66 #define __BITOPS_ALIGN		3
67 #define __BITOPS_WORDSIZE	32
68 #define __BITOPS_OR		"or"
69 #define __BITOPS_AND		"nr"
70 #define __BITOPS_XOR		"xr"
71 
72 #define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)	\
73 	asm volatile(						\
74 		"	l	%0,%2\n"			\
75 		"0:	lr	%1,%0\n"			\
76 		__op_string "	%1,%3\n"			\
77 		"	cs	%0,%1,%2\n"			\
78 		"	jl	0b"				\
79 		: "=&d" (__old), "=&d" (__new),			\
80 		  "=Q" (*(unsigned long *) __addr)		\
81 		: "d" (__val), "Q" (*(unsigned long *) __addr)	\
82 		: "cc");
83 
84 #else /* CONFIG_64BIT */
85 
86 #define __BITOPS_ALIGN		7
87 #define __BITOPS_WORDSIZE	64
88 #define __BITOPS_OR		"ogr"
89 #define __BITOPS_AND		"ngr"
90 #define __BITOPS_XOR		"xgr"
91 
92 #define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)	\
93 	asm volatile(						\
94 		"	lg	%0,%2\n"			\
95 		"0:	lgr	%1,%0\n"			\
96 		__op_string "	%1,%3\n"			\
97 		"	csg	%0,%1,%2\n"			\
98 		"	jl	0b"				\
99 		: "=&d" (__old), "=&d" (__new),			\
100 		  "=Q" (*(unsigned long *) __addr)		\
101 		: "d" (__val), "Q" (*(unsigned long *) __addr)	\
102 		: "cc");
103 
104 #endif /* CONFIG_64BIT */
105 
106 #define __BITOPS_WORDS(bits) (((bits)+__BITOPS_WORDSIZE-1)/__BITOPS_WORDSIZE)
107 #define __BITOPS_BARRIER() asm volatile("" : : : "memory")
108 
109 #ifdef CONFIG_SMP
110 /*
111  * SMP safe set_bit routine based on compare and swap (CS)
112  */
113 static inline void set_bit_cs(unsigned long nr, volatile unsigned long *ptr)
114 {
115         unsigned long addr, old, new, mask;
116 
117 	addr = (unsigned long) ptr;
118 	/* calculate address for CS */
119 	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
120 	/* make OR mask */
121 	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
122 	/* Do the atomic update. */
123 	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_OR);
124 }
125 
126 /*
127  * SMP safe clear_bit routine based on compare and swap (CS)
128  */
129 static inline void clear_bit_cs(unsigned long nr, volatile unsigned long *ptr)
130 {
131         unsigned long addr, old, new, mask;
132 
133 	addr = (unsigned long) ptr;
134 	/* calculate address for CS */
135 	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
136 	/* make AND mask */
137 	mask = ~(1UL << (nr & (__BITOPS_WORDSIZE - 1)));
138 	/* Do the atomic update. */
139 	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_AND);
140 }
141 
142 /*
143  * SMP safe change_bit routine based on compare and swap (CS)
144  */
145 static inline void change_bit_cs(unsigned long nr, volatile unsigned long *ptr)
146 {
147         unsigned long addr, old, new, mask;
148 
149 	addr = (unsigned long) ptr;
150 	/* calculate address for CS */
151 	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
152 	/* make XOR mask */
153 	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
154 	/* Do the atomic update. */
155 	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_XOR);
156 }
157 
158 /*
159  * SMP safe test_and_set_bit routine based on compare and swap (CS)
160  */
161 static inline int
162 test_and_set_bit_cs(unsigned long nr, volatile unsigned long *ptr)
163 {
164         unsigned long addr, old, new, mask;
165 
166 	addr = (unsigned long) ptr;
167 	/* calculate address for CS */
168 	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
169 	/* make OR/test mask */
170 	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
171 	/* Do the atomic update. */
172 	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_OR);
173 	__BITOPS_BARRIER();
174 	return (old & mask) != 0;
175 }
176 
177 /*
178  * SMP safe test_and_clear_bit routine based on compare and swap (CS)
179  */
180 static inline int
181 test_and_clear_bit_cs(unsigned long nr, volatile unsigned long *ptr)
182 {
183         unsigned long addr, old, new, mask;
184 
185 	addr = (unsigned long) ptr;
186 	/* calculate address for CS */
187 	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
188 	/* make AND/test mask */
189 	mask = ~(1UL << (nr & (__BITOPS_WORDSIZE - 1)));
190 	/* Do the atomic update. */
191 	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_AND);
192 	__BITOPS_BARRIER();
193 	return (old ^ new) != 0;
194 }
195 
196 /*
197  * SMP safe test_and_change_bit routine based on compare and swap (CS)
198  */
199 static inline int
200 test_and_change_bit_cs(unsigned long nr, volatile unsigned long *ptr)
201 {
202         unsigned long addr, old, new, mask;
203 
204 	addr = (unsigned long) ptr;
205 	/* calculate address for CS */
206 	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
207 	/* make XOR/test mask */
208 	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
209 	/* Do the atomic update. */
210 	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_XOR);
211 	__BITOPS_BARRIER();
212 	return (old & mask) != 0;
213 }
214 #endif /* CONFIG_SMP */
215 
216 /*
217  * fast, non-SMP set_bit routine
218  */
219 static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
220 {
221 	unsigned long addr;
222 
223 	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
224 	asm volatile(
225 		"	oc	%O0(1,%R0),%1"
226 		: "=Q" (*(char *) addr) : "Q" (_oi_bitmap[nr & 7]) : "cc" );
227 }
228 
229 static inline void
230 __constant_set_bit(const unsigned long nr, volatile unsigned long *ptr)
231 {
232 	unsigned long addr;
233 
234 	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
235 	*(unsigned char *) addr |= 1 << (nr & 7);
236 }
237 
238 #define set_bit_simple(nr,addr) \
239 (__builtin_constant_p((nr)) ? \
240  __constant_set_bit((nr),(addr)) : \
241  __set_bit((nr),(addr)) )
242 
243 /*
244  * fast, non-SMP clear_bit routine
245  */
246 static inline void
247 __clear_bit(unsigned long nr, volatile unsigned long *ptr)
248 {
249 	unsigned long addr;
250 
251 	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
252 	asm volatile(
253 		"	nc	%O0(1,%R0),%1"
254 		: "=Q" (*(char *) addr) : "Q" (_ni_bitmap[nr & 7]) : "cc" );
255 }
256 
257 static inline void
258 __constant_clear_bit(const unsigned long nr, volatile unsigned long *ptr)
259 {
260 	unsigned long addr;
261 
262 	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
263 	*(unsigned char *) addr &= ~(1 << (nr & 7));
264 }
265 
266 #define clear_bit_simple(nr,addr) \
267 (__builtin_constant_p((nr)) ? \
268  __constant_clear_bit((nr),(addr)) : \
269  __clear_bit((nr),(addr)) )
270 
271 /*
272  * fast, non-SMP change_bit routine
273  */
274 static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
275 {
276 	unsigned long addr;
277 
278 	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
279 	asm volatile(
280 		"	xc	%O0(1,%R0),%1"
281 		: "=Q" (*(char *) addr) : "Q" (_oi_bitmap[nr & 7]) : "cc" );
282 }
283 
284 static inline void
285 __constant_change_bit(const unsigned long nr, volatile unsigned long *ptr)
286 {
287 	unsigned long addr;
288 
289 	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
290 	*(unsigned char *) addr ^= 1 << (nr & 7);
291 }
292 
293 #define change_bit_simple(nr,addr) \
294 (__builtin_constant_p((nr)) ? \
295  __constant_change_bit((nr),(addr)) : \
296  __change_bit((nr),(addr)) )
297 
298 /*
299  * fast, non-SMP test_and_set_bit routine
300  */
301 static inline int
302 test_and_set_bit_simple(unsigned long nr, volatile unsigned long *ptr)
303 {
304 	unsigned long addr;
305 	unsigned char ch;
306 
307 	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
308 	ch = *(unsigned char *) addr;
309 	asm volatile(
310 		"	oc	%O0(1,%R0),%1"
311 		: "=Q" (*(char *) addr)	: "Q" (_oi_bitmap[nr & 7])
312 		: "cc", "memory");
313 	return (ch >> (nr & 7)) & 1;
314 }
315 #define __test_and_set_bit(X,Y)		test_and_set_bit_simple(X,Y)
316 
317 /*
318  * fast, non-SMP test_and_clear_bit routine
319  */
320 static inline int
321 test_and_clear_bit_simple(unsigned long nr, volatile unsigned long *ptr)
322 {
323 	unsigned long addr;
324 	unsigned char ch;
325 
326 	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
327 	ch = *(unsigned char *) addr;
328 	asm volatile(
329 		"	nc	%O0(1,%R0),%1"
330 		: "=Q" (*(char *) addr)	: "Q" (_ni_bitmap[nr & 7])
331 		: "cc", "memory");
332 	return (ch >> (nr & 7)) & 1;
333 }
334 #define __test_and_clear_bit(X,Y)	test_and_clear_bit_simple(X,Y)
335 
336 /*
337  * fast, non-SMP test_and_change_bit routine
338  */
339 static inline int
340 test_and_change_bit_simple(unsigned long nr, volatile unsigned long *ptr)
341 {
342 	unsigned long addr;
343 	unsigned char ch;
344 
345 	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
346 	ch = *(unsigned char *) addr;
347 	asm volatile(
348 		"	xc	%O0(1,%R0),%1"
349 		: "=Q" (*(char *) addr)	: "Q" (_oi_bitmap[nr & 7])
350 		: "cc", "memory");
351 	return (ch >> (nr & 7)) & 1;
352 }
353 #define __test_and_change_bit(X,Y)	test_and_change_bit_simple(X,Y)
354 
355 #ifdef CONFIG_SMP
356 #define set_bit             set_bit_cs
357 #define clear_bit           clear_bit_cs
358 #define change_bit          change_bit_cs
359 #define test_and_set_bit    test_and_set_bit_cs
360 #define test_and_clear_bit  test_and_clear_bit_cs
361 #define test_and_change_bit test_and_change_bit_cs
362 #else
363 #define set_bit             set_bit_simple
364 #define clear_bit           clear_bit_simple
365 #define change_bit          change_bit_simple
366 #define test_and_set_bit    test_and_set_bit_simple
367 #define test_and_clear_bit  test_and_clear_bit_simple
368 #define test_and_change_bit test_and_change_bit_simple
369 #endif
370 
371 
372 /*
373  * This routine doesn't need to be atomic.
374  */
375 
376 static inline int __test_bit(unsigned long nr, const volatile unsigned long *ptr)
377 {
378 	unsigned long addr;
379 	unsigned char ch;
380 
381 	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
382 	ch = *(volatile unsigned char *) addr;
383 	return (ch >> (nr & 7)) & 1;
384 }
385 
386 static inline int
387 __constant_test_bit(unsigned long nr, const volatile unsigned long *addr) {
388     return (((volatile char *) addr)
389 	    [(nr^(__BITOPS_WORDSIZE-8))>>3] & (1<<(nr&7))) != 0;
390 }
391 
392 #define test_bit(nr,addr) \
393 (__builtin_constant_p((nr)) ? \
394  __constant_test_bit((nr),(addr)) : \
395  __test_bit((nr),(addr)) )
396 
397 /*
398  * Optimized find bit helper functions.
399  */
400 
401 /**
402  * __ffz_word_loop - find byte offset of first long != -1UL
403  * @addr: pointer to array of unsigned long
404  * @size: size of the array in bits
405  */
406 static inline unsigned long __ffz_word_loop(const unsigned long *addr,
407 					    unsigned long size)
408 {
409 	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
410 	unsigned long bytes = 0;
411 
412 	asm volatile(
413 #ifndef CONFIG_64BIT
414 		"	ahi	%1,-1\n"
415 		"	sra	%1,5\n"
416 		"	jz	1f\n"
417 		"0:	c	%2,0(%0,%3)\n"
418 		"	jne	1f\n"
419 		"	la	%0,4(%0)\n"
420 		"	brct	%1,0b\n"
421 		"1:\n"
422 #else
423 		"	aghi	%1,-1\n"
424 		"	srag	%1,%1,6\n"
425 		"	jz	1f\n"
426 		"0:	cg	%2,0(%0,%3)\n"
427 		"	jne	1f\n"
428 		"	la	%0,8(%0)\n"
429 		"	brct	%1,0b\n"
430 		"1:\n"
431 #endif
432 		: "+&a" (bytes), "+&d" (size)
433 		: "d" (-1UL), "a" (addr), "m" (*(addrtype *) addr)
434 		: "cc" );
435 	return bytes;
436 }
437 
438 /**
439  * __ffs_word_loop - find byte offset of first long != 0UL
440  * @addr: pointer to array of unsigned long
441  * @size: size of the array in bits
442  */
443 static inline unsigned long __ffs_word_loop(const unsigned long *addr,
444 					    unsigned long size)
445 {
446 	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
447 	unsigned long bytes = 0;
448 
449 	asm volatile(
450 #ifndef CONFIG_64BIT
451 		"	ahi	%1,-1\n"
452 		"	sra	%1,5\n"
453 		"	jz	1f\n"
454 		"0:	c	%2,0(%0,%3)\n"
455 		"	jne	1f\n"
456 		"	la	%0,4(%0)\n"
457 		"	brct	%1,0b\n"
458 		"1:\n"
459 #else
460 		"	aghi	%1,-1\n"
461 		"	srag	%1,%1,6\n"
462 		"	jz	1f\n"
463 		"0:	cg	%2,0(%0,%3)\n"
464 		"	jne	1f\n"
465 		"	la	%0,8(%0)\n"
466 		"	brct	%1,0b\n"
467 		"1:\n"
468 #endif
469 		: "+&a" (bytes), "+&a" (size)
470 		: "d" (0UL), "a" (addr), "m" (*(addrtype *) addr)
471 		: "cc" );
472 	return bytes;
473 }
474 
475 /**
476  * __ffz_word - add number of the first unset bit
477  * @nr: base value the bit number is added to
478  * @word: the word that is searched for unset bits
479  */
480 static inline unsigned long __ffz_word(unsigned long nr, unsigned long word)
481 {
482 #ifdef CONFIG_64BIT
483 	if ((word & 0xffffffff) == 0xffffffff) {
484 		word >>= 32;
485 		nr += 32;
486 	}
487 #endif
488 	if ((word & 0xffff) == 0xffff) {
489 		word >>= 16;
490 		nr += 16;
491 	}
492 	if ((word & 0xff) == 0xff) {
493 		word >>= 8;
494 		nr += 8;
495 	}
496 	return nr + _zb_findmap[(unsigned char) word];
497 }
498 
499 /**
500  * __ffs_word - add number of the first set bit
501  * @nr: base value the bit number is added to
502  * @word: the word that is searched for set bits
503  */
504 static inline unsigned long __ffs_word(unsigned long nr, unsigned long word)
505 {
506 #ifdef CONFIG_64BIT
507 	if ((word & 0xffffffff) == 0) {
508 		word >>= 32;
509 		nr += 32;
510 	}
511 #endif
512 	if ((word & 0xffff) == 0) {
513 		word >>= 16;
514 		nr += 16;
515 	}
516 	if ((word & 0xff) == 0) {
517 		word >>= 8;
518 		nr += 8;
519 	}
520 	return nr + _sb_findmap[(unsigned char) word];
521 }
522 
523 
524 /**
525  * __load_ulong_be - load big endian unsigned long
526  * @p: pointer to array of unsigned long
527  * @offset: byte offset of source value in the array
528  */
529 static inline unsigned long __load_ulong_be(const unsigned long *p,
530 					    unsigned long offset)
531 {
532 	p = (unsigned long *)((unsigned long) p + offset);
533 	return *p;
534 }
535 
536 /**
537  * __load_ulong_le - load little endian unsigned long
538  * @p: pointer to array of unsigned long
539  * @offset: byte offset of source value in the array
540  */
541 static inline unsigned long __load_ulong_le(const unsigned long *p,
542 					    unsigned long offset)
543 {
544 	unsigned long word;
545 
546 	p = (unsigned long *)((unsigned long) p + offset);
547 #ifndef CONFIG_64BIT
548 	asm volatile(
549 		"	ic	%0,%O1(%R1)\n"
550 		"	icm	%0,2,%O1+1(%R1)\n"
551 		"	icm	%0,4,%O1+2(%R1)\n"
552 		"	icm	%0,8,%O1+3(%R1)"
553 		: "=&d" (word) : "Q" (*p) : "cc");
554 #else
555 	asm volatile(
556 		"	lrvg	%0,%1"
557 		: "=d" (word) : "m" (*p) );
558 #endif
559 	return word;
560 }
561 
562 /*
563  * The various find bit functions.
564  */
565 
566 /*
567  * ffz - find first zero in word.
568  * @word: The word to search
569  *
570  * Undefined if no zero exists, so code should check against ~0UL first.
571  */
572 static inline unsigned long ffz(unsigned long word)
573 {
574 	return __ffz_word(0, word);
575 }
576 
577 /**
578  * __ffs - find first bit in word.
579  * @word: The word to search
580  *
581  * Undefined if no bit exists, so code should check against 0 first.
582  */
583 static inline unsigned long __ffs (unsigned long word)
584 {
585 	return __ffs_word(0, word);
586 }
587 
588 /**
589  * ffs - find first bit set
590  * @x: the word to search
591  *
592  * This is defined the same way as
593  * the libc and compiler builtin ffs routines, therefore
594  * differs in spirit from the above ffz (man ffs).
595  */
596 static inline int ffs(int x)
597 {
598 	if (!x)
599 		return 0;
600 	return __ffs_word(1, x);
601 }
602 
603 /**
604  * find_first_zero_bit - find the first zero bit in a memory region
605  * @addr: The address to start the search at
606  * @size: The maximum size to search
607  *
608  * Returns the bit-number of the first zero bit, not the number of the byte
609  * containing a bit.
610  */
611 static inline unsigned long find_first_zero_bit(const unsigned long *addr,
612 						unsigned long size)
613 {
614 	unsigned long bytes, bits;
615 
616         if (!size)
617                 return 0;
618 	bytes = __ffz_word_loop(addr, size);
619 	bits = __ffz_word(bytes*8, __load_ulong_be(addr, bytes));
620 	return (bits < size) ? bits : size;
621 }
622 #define find_first_zero_bit find_first_zero_bit
623 
624 /**
625  * find_first_bit - find the first set bit in a memory region
626  * @addr: The address to start the search at
627  * @size: The maximum size to search
628  *
629  * Returns the bit-number of the first set bit, not the number of the byte
630  * containing a bit.
631  */
632 static inline unsigned long find_first_bit(const unsigned long * addr,
633 					   unsigned long size)
634 {
635 	unsigned long bytes, bits;
636 
637         if (!size)
638                 return 0;
639 	bytes = __ffs_word_loop(addr, size);
640 	bits = __ffs_word(bytes*8, __load_ulong_be(addr, bytes));
641 	return (bits < size) ? bits : size;
642 }
643 #define find_first_bit find_first_bit
644 
645 /**
646  * find_next_zero_bit - find the first zero bit in a memory region
647  * @addr: The address to base the search on
648  * @offset: The bitnumber to start searching at
649  * @size: The maximum size to search
650  */
651 static inline int find_next_zero_bit (const unsigned long * addr,
652 				      unsigned long size,
653 				      unsigned long offset)
654 {
655         const unsigned long *p;
656 	unsigned long bit, set;
657 
658 	if (offset >= size)
659 		return size;
660 	bit = offset & (__BITOPS_WORDSIZE - 1);
661 	offset -= bit;
662 	size -= offset;
663 	p = addr + offset / __BITOPS_WORDSIZE;
664 	if (bit) {
665 		/*
666 		 * __ffz_word returns __BITOPS_WORDSIZE
667 		 * if no zero bit is present in the word.
668 		 */
669 		set = __ffz_word(bit, *p >> bit);
670 		if (set >= size)
671 			return size + offset;
672 		if (set < __BITOPS_WORDSIZE)
673 			return set + offset;
674 		offset += __BITOPS_WORDSIZE;
675 		size -= __BITOPS_WORDSIZE;
676 		p++;
677 	}
678 	return offset + find_first_zero_bit(p, size);
679 }
680 #define find_next_zero_bit find_next_zero_bit
681 
682 /**
683  * find_next_bit - find the first set bit in a memory region
684  * @addr: The address to base the search on
685  * @offset: The bitnumber to start searching at
686  * @size: The maximum size to search
687  */
688 static inline int find_next_bit (const unsigned long * addr,
689 				 unsigned long size,
690 				 unsigned long offset)
691 {
692         const unsigned long *p;
693 	unsigned long bit, set;
694 
695 	if (offset >= size)
696 		return size;
697 	bit = offset & (__BITOPS_WORDSIZE - 1);
698 	offset -= bit;
699 	size -= offset;
700 	p = addr + offset / __BITOPS_WORDSIZE;
701 	if (bit) {
702 		/*
703 		 * __ffs_word returns __BITOPS_WORDSIZE
704 		 * if no one bit is present in the word.
705 		 */
706 		set = __ffs_word(0, *p & (~0UL << bit));
707 		if (set >= size)
708 			return size + offset;
709 		if (set < __BITOPS_WORDSIZE)
710 			return set + offset;
711 		offset += __BITOPS_WORDSIZE;
712 		size -= __BITOPS_WORDSIZE;
713 		p++;
714 	}
715 	return offset + find_first_bit(p, size);
716 }
717 #define find_next_bit find_next_bit
718 
719 /*
720  * Every architecture must define this function. It's the fastest
721  * way of searching a 140-bit bitmap where the first 100 bits are
722  * unlikely to be set. It's guaranteed that at least one of the 140
723  * bits is cleared.
724  */
725 static inline int sched_find_first_bit(unsigned long *b)
726 {
727 	return find_first_bit(b, 140);
728 }
729 
730 #include <asm-generic/bitops/fls.h>
731 #include <asm-generic/bitops/__fls.h>
732 #include <asm-generic/bitops/fls64.h>
733 
734 #include <asm-generic/bitops/hweight.h>
735 #include <asm-generic/bitops/lock.h>
736 
737 /*
738  * ATTENTION: intel byte ordering convention for ext2 and minix !!
739  * bit 0 is the LSB of addr; bit 31 is the MSB of addr;
740  * bit 32 is the LSB of (addr+4).
741  * That combined with the little endian byte order of Intel gives the
742  * following bit order in memory:
743  *    07 06 05 04 03 02 01 00 15 14 13 12 11 10 09 08 \
744  *    23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24
745  */
746 
747 static inline int find_first_zero_bit_le(void *vaddr, unsigned int size)
748 {
749 	unsigned long bytes, bits;
750 
751         if (!size)
752                 return 0;
753 	bytes = __ffz_word_loop(vaddr, size);
754 	bits = __ffz_word(bytes*8, __load_ulong_le(vaddr, bytes));
755 	return (bits < size) ? bits : size;
756 }
757 #define find_first_zero_bit_le find_first_zero_bit_le
758 
759 static inline int find_next_zero_bit_le(void *vaddr, unsigned long size,
760 					  unsigned long offset)
761 {
762         unsigned long *addr = vaddr, *p;
763 	unsigned long bit, set;
764 
765         if (offset >= size)
766                 return size;
767 	bit = offset & (__BITOPS_WORDSIZE - 1);
768 	offset -= bit;
769 	size -= offset;
770 	p = addr + offset / __BITOPS_WORDSIZE;
771         if (bit) {
772 		/*
773 		 * s390 version of ffz returns __BITOPS_WORDSIZE
774 		 * if no zero bit is present in the word.
775 		 */
776 		set = __ffz_word(bit, __load_ulong_le(p, 0) >> bit);
777 		if (set >= size)
778 			return size + offset;
779 		if (set < __BITOPS_WORDSIZE)
780 			return set + offset;
781 		offset += __BITOPS_WORDSIZE;
782 		size -= __BITOPS_WORDSIZE;
783 		p++;
784         }
785 	return offset + find_first_zero_bit_le(p, size);
786 }
787 #define find_next_zero_bit_le find_next_zero_bit_le
788 
789 static inline unsigned long find_first_bit_le(void *vaddr, unsigned long size)
790 {
791 	unsigned long bytes, bits;
792 
793 	if (!size)
794 		return 0;
795 	bytes = __ffs_word_loop(vaddr, size);
796 	bits = __ffs_word(bytes*8, __load_ulong_le(vaddr, bytes));
797 	return (bits < size) ? bits : size;
798 }
799 #define find_first_bit_le find_first_bit_le
800 
801 static inline int find_next_bit_le(void *vaddr, unsigned long size,
802 				     unsigned long offset)
803 {
804 	unsigned long *addr = vaddr, *p;
805 	unsigned long bit, set;
806 
807 	if (offset >= size)
808 		return size;
809 	bit = offset & (__BITOPS_WORDSIZE - 1);
810 	offset -= bit;
811 	size -= offset;
812 	p = addr + offset / __BITOPS_WORDSIZE;
813 	if (bit) {
814 		/*
815 		 * s390 version of ffz returns __BITOPS_WORDSIZE
816 		 * if no zero bit is present in the word.
817 		 */
818 		set = __ffs_word(0, __load_ulong_le(p, 0) & (~0UL << bit));
819 		if (set >= size)
820 			return size + offset;
821 		if (set < __BITOPS_WORDSIZE)
822 			return set + offset;
823 		offset += __BITOPS_WORDSIZE;
824 		size -= __BITOPS_WORDSIZE;
825 		p++;
826 	}
827 	return offset + find_first_bit_le(p, size);
828 }
829 #define find_next_bit_le find_next_bit_le
830 
831 #include <asm-generic/bitops/le.h>
832 
833 #include <asm-generic/bitops/ext2-atomic-setbit.h>
834 
835 #endif /* _S390_BITOPS_H */
836