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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _ASM_IA64_BITOPS_H
2#define _ASM_IA64_BITOPS_H
3
4/*
5 * Copyright (C) 1998-2003 Hewlett-Packard Co
6 * David Mosberger-Tang <davidm@hpl.hp.com>
7 *
Akinobu Mita2875aef2006-03-26 01:39:25 -08008 * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64
9 * O(1) scheduler patch
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 */
11
Jiri Slaby06245172007-10-18 23:40:26 -070012#ifndef _LINUX_BITOPS_H
13#error only <linux/bitops.h> can be included directly
14#endif
15
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/compiler.h>
17#include <linux/types.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <asm/intrinsics.h>
19
20/**
21 * set_bit - Atomically set a bit in memory
22 * @nr: the bit to set
23 * @addr: the address to start counting from
24 *
25 * This function is atomic and may not be reordered. See __set_bit()
26 * if you do not require the atomic guarantees.
27 * Note that @nr may be almost arbitrarily large; this function is not
28 * restricted to acting on a single-word quantity.
29 *
30 * The address must be (at least) "long" aligned.
Akinobu Mita2875aef2006-03-26 01:39:25 -080031 * Note that there are driver (e.g., eepro100) which use these operations to
32 * operate on hw-defined data-structures, so we can't easily change these
33 * operations to force a bigger alignment.
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 *
35 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
36 */
37static __inline__ void
38set_bit (int nr, volatile void *addr)
39{
40 __u32 bit, old, new;
41 volatile __u32 *m;
42 CMPXCHG_BUGCHECK_DECL
43
44 m = (volatile __u32 *) addr + (nr >> 5);
45 bit = 1 << (nr & 31);
46 do {
47 CMPXCHG_BUGCHECK(m);
48 old = *m;
49 new = old | bit;
50 } while (cmpxchg_acq(m, old, new) != old);
51}
52
53/**
54 * __set_bit - Set a bit in memory
55 * @nr: the bit to set
56 * @addr: the address to start counting from
57 *
58 * Unlike set_bit(), this function is non-atomic and may be reordered.
59 * If it's called on the same region of memory simultaneously, the effect
60 * may be that only one operation succeeds.
61 */
62static __inline__ void
63__set_bit (int nr, volatile void *addr)
64{
65 *((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31));
66}
67
68/*
69 * clear_bit() has "acquire" semantics.
70 */
71#define smp_mb__before_clear_bit() smp_mb()
72#define smp_mb__after_clear_bit() do { /* skip */; } while (0)
73
74/**
75 * clear_bit - Clears a bit in memory
76 * @nr: Bit to clear
77 * @addr: Address to start counting from
78 *
79 * clear_bit() is atomic and may not be reordered. However, it does
80 * not contain a memory barrier, so if it is used for locking purposes,
81 * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
82 * in order to ensure changes are visible on other processors.
83 */
84static __inline__ void
85clear_bit (int nr, volatile void *addr)
86{
87 __u32 mask, old, new;
88 volatile __u32 *m;
89 CMPXCHG_BUGCHECK_DECL
90
91 m = (volatile __u32 *) addr + (nr >> 5);
92 mask = ~(1 << (nr & 31));
93 do {
94 CMPXCHG_BUGCHECK(m);
95 old = *m;
96 new = old & mask;
97 } while (cmpxchg_acq(m, old, new) != old);
98}
99
100/**
Nick Piggin87371e42007-10-18 03:06:52 -0700101 * clear_bit_unlock - Clears a bit in memory with release
102 * @nr: Bit to clear
103 * @addr: Address to start counting from
104 *
105 * clear_bit_unlock() is atomic and may not be reordered. It does
106 * contain a memory barrier suitable for unlock type operations.
107 */
108static __inline__ void
109clear_bit_unlock (int nr, volatile void *addr)
110{
111 __u32 mask, old, new;
112 volatile __u32 *m;
113 CMPXCHG_BUGCHECK_DECL
114
115 m = (volatile __u32 *) addr + (nr >> 5);
116 mask = ~(1 << (nr & 31));
117 do {
118 CMPXCHG_BUGCHECK(m);
119 old = *m;
120 new = old & mask;
121 } while (cmpxchg_rel(m, old, new) != old);
122}
123
124/**
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800125 * __clear_bit_unlock - Non-atomically clears a bit in memory with release
126 * @nr: Bit to clear
127 * @addr: Address to start counting from
Nick Piggin87371e42007-10-18 03:06:52 -0700128 *
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800129 * Similarly to clear_bit_unlock, the implementation uses a store
Christoph Lametera3ebdb62007-12-18 16:22:46 -0800130 * with release semantics. See also __raw_spin_unlock().
Nick Piggin87371e42007-10-18 03:06:52 -0700131 */
Christoph Lametera3ebdb62007-12-18 16:22:46 -0800132static __inline__ void
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800133__clear_bit_unlock(int nr, void *addr)
Christoph Lametera3ebdb62007-12-18 16:22:46 -0800134{
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800135 __u32 * const m = (__u32 *) addr + (nr >> 5);
136 __u32 const new = *m & ~(1 << (nr & 31));
Christoph Lametera3ebdb62007-12-18 16:22:46 -0800137
Christoph Lametera3ebdb62007-12-18 16:22:46 -0800138 ia64_st4_rel_nta(m, new);
139}
Nick Piggin87371e42007-10-18 03:06:52 -0700140
141/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 * __clear_bit - Clears a bit in memory (non-atomic version)
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800143 * @nr: the bit to clear
144 * @addr: the address to start counting from
145 *
146 * Unlike clear_bit(), this function is non-atomic and may be reordered.
147 * If it's called on the same region of memory simultaneously, the effect
148 * may be that only one operation succeeds.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 */
150static __inline__ void
151__clear_bit (int nr, volatile void *addr)
152{
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800153 *((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154}
155
156/**
157 * change_bit - Toggle a bit in memory
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800158 * @nr: Bit to toggle
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 * @addr: Address to start counting from
160 *
161 * change_bit() is atomic and may not be reordered.
162 * Note that @nr may be almost arbitrarily large; this function is not
163 * restricted to acting on a single-word quantity.
164 */
165static __inline__ void
166change_bit (int nr, volatile void *addr)
167{
168 __u32 bit, old, new;
169 volatile __u32 *m;
170 CMPXCHG_BUGCHECK_DECL
171
172 m = (volatile __u32 *) addr + (nr >> 5);
173 bit = (1 << (nr & 31));
174 do {
175 CMPXCHG_BUGCHECK(m);
176 old = *m;
177 new = old ^ bit;
178 } while (cmpxchg_acq(m, old, new) != old);
179}
180
181/**
182 * __change_bit - Toggle a bit in memory
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800183 * @nr: the bit to toggle
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 * @addr: the address to start counting from
185 *
186 * Unlike change_bit(), this function is non-atomic and may be reordered.
187 * If it's called on the same region of memory simultaneously, the effect
188 * may be that only one operation succeeds.
189 */
190static __inline__ void
191__change_bit (int nr, volatile void *addr)
192{
193 *((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31));
194}
195
196/**
197 * test_and_set_bit - Set a bit and return its old value
198 * @nr: Bit to set
199 * @addr: Address to count from
200 *
201 * This operation is atomic and cannot be reordered.
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800202 * It also implies the acquisition side of the memory barrier.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 */
204static __inline__ int
205test_and_set_bit (int nr, volatile void *addr)
206{
207 __u32 bit, old, new;
208 volatile __u32 *m;
209 CMPXCHG_BUGCHECK_DECL
210
211 m = (volatile __u32 *) addr + (nr >> 5);
212 bit = 1 << (nr & 31);
213 do {
214 CMPXCHG_BUGCHECK(m);
215 old = *m;
216 new = old | bit;
217 } while (cmpxchg_acq(m, old, new) != old);
218 return (old & bit) != 0;
219}
220
221/**
Nick Piggin87371e42007-10-18 03:06:52 -0700222 * test_and_set_bit_lock - Set a bit and return its old value for lock
223 * @nr: Bit to set
224 * @addr: Address to count from
225 *
226 * This is the same as test_and_set_bit on ia64
227 */
228#define test_and_set_bit_lock test_and_set_bit
229
230/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 * __test_and_set_bit - Set a bit and return its old value
232 * @nr: Bit to set
233 * @addr: Address to count from
234 *
235 * This operation is non-atomic and can be reordered.
236 * If two examples of this operation race, one can appear to succeed
237 * but actually fail. You must protect multiple accesses with a lock.
238 */
239static __inline__ int
240__test_and_set_bit (int nr, volatile void *addr)
241{
242 __u32 *p = (__u32 *) addr + (nr >> 5);
243 __u32 m = 1 << (nr & 31);
244 int oldbitset = (*p & m) != 0;
245
246 *p |= m;
247 return oldbitset;
248}
249
250/**
251 * test_and_clear_bit - Clear a bit and return its old value
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800252 * @nr: Bit to clear
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 * @addr: Address to count from
254 *
255 * This operation is atomic and cannot be reordered.
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800256 * It also implies the acquisition side of the memory barrier.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 */
258static __inline__ int
259test_and_clear_bit (int nr, volatile void *addr)
260{
261 __u32 mask, old, new;
262 volatile __u32 *m;
263 CMPXCHG_BUGCHECK_DECL
264
265 m = (volatile __u32 *) addr + (nr >> 5);
266 mask = ~(1 << (nr & 31));
267 do {
268 CMPXCHG_BUGCHECK(m);
269 old = *m;
270 new = old & mask;
271 } while (cmpxchg_acq(m, old, new) != old);
272 return (old & ~mask) != 0;
273}
274
275/**
276 * __test_and_clear_bit - Clear a bit and return its old value
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800277 * @nr: Bit to clear
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 * @addr: Address to count from
279 *
280 * This operation is non-atomic and can be reordered.
281 * If two examples of this operation race, one can appear to succeed
282 * but actually fail. You must protect multiple accesses with a lock.
283 */
284static __inline__ int
285__test_and_clear_bit(int nr, volatile void * addr)
286{
287 __u32 *p = (__u32 *) addr + (nr >> 5);
288 __u32 m = 1 << (nr & 31);
Johannes Weiner8d6f9af2009-08-11 14:52:10 -0700289 int oldbitset = (*p & m) != 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290
291 *p &= ~m;
292 return oldbitset;
293}
294
295/**
296 * test_and_change_bit - Change a bit and return its old value
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800297 * @nr: Bit to change
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 * @addr: Address to count from
299 *
300 * This operation is atomic and cannot be reordered.
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800301 * It also implies the acquisition side of the memory barrier.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 */
303static __inline__ int
304test_and_change_bit (int nr, volatile void *addr)
305{
306 __u32 bit, old, new;
307 volatile __u32 *m;
308 CMPXCHG_BUGCHECK_DECL
309
310 m = (volatile __u32 *) addr + (nr >> 5);
311 bit = (1 << (nr & 31));
312 do {
313 CMPXCHG_BUGCHECK(m);
314 old = *m;
315 new = old ^ bit;
316 } while (cmpxchg_acq(m, old, new) != old);
317 return (old & bit) != 0;
318}
319
Zoltan Menyhart5302ac52008-02-04 15:19:16 -0800320/**
321 * __test_and_change_bit - Change a bit and return its old value
322 * @nr: Bit to change
323 * @addr: Address to count from
324 *
325 * This operation is non-atomic and can be reordered.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 */
327static __inline__ int
328__test_and_change_bit (int nr, void *addr)
329{
330 __u32 old, bit = (1 << (nr & 31));
331 __u32 *m = (__u32 *) addr + (nr >> 5);
332
333 old = *m;
334 *m = old ^ bit;
335 return (old & bit) != 0;
336}
337
338static __inline__ int
339test_bit (int nr, const volatile void *addr)
340{
341 return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31));
342}
343
344/**
345 * ffz - find the first zero bit in a long word
346 * @x: The long word to find the bit in
347 *
Akinobu Mita2875aef2006-03-26 01:39:25 -0800348 * Returns the bit-number (0..63) of the first (least significant) zero bit.
349 * Undefined if no zero exists, so code should check against ~0UL first...
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 */
351static inline unsigned long
352ffz (unsigned long x)
353{
354 unsigned long result;
355
356 result = ia64_popcnt(x & (~x - 1));
357 return result;
358}
359
360/**
361 * __ffs - find first bit in word.
362 * @x: The word to search
363 *
364 * Undefined if no bit exists, so code should check against 0 first.
365 */
366static __inline__ unsigned long
367__ffs (unsigned long x)
368{
369 unsigned long result;
370
371 result = ia64_popcnt((x-1) & ~x);
372 return result;
373}
374
375#ifdef __KERNEL__
376
377/*
David Mosberger-Tang821376b2005-04-21 11:07:59 -0700378 * Return bit number of last (most-significant) bit set. Undefined
379 * for x==0. Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 */
381static inline unsigned long
382ia64_fls (unsigned long x)
383{
384 long double d = x;
385 long exp;
386
387 exp = ia64_getf_exp(d);
388 return exp - 0xffff;
389}
390
David Mosberger-Tang821376b2005-04-21 11:07:59 -0700391/*
392 * Find the last (most significant) bit set. Returns 0 for x==0 and
393 * bits are numbered from 1..32 (e.g., fls(9) == 4).
394 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395static inline int
David Mosberger-Tang821376b2005-04-21 11:07:59 -0700396fls (int t)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397{
David Mosberger-Tang821376b2005-04-21 11:07:59 -0700398 unsigned long x = t & 0xffffffffu;
399
400 if (!x)
401 return 0;
402 x |= x >> 1;
403 x |= x >> 2;
404 x |= x >> 4;
405 x |= x >> 8;
406 x |= x >> 16;
407 return ia64_popcnt(x);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408}
Akinobu Mita2875aef2006-03-26 01:39:25 -0800409
Alexander van Heukelum56a6b1e2008-03-15 18:31:49 +0100410/*
411 * Find the last (most significant) bit set. Undefined for x==0.
412 * Bits are numbered from 0..63 (e.g., __fls(9) == 3).
413 */
414static inline unsigned long
415__fls (unsigned long x)
416{
417 x |= x >> 1;
418 x |= x >> 2;
419 x |= x >> 4;
420 x |= x >> 8;
421 x |= x >> 16;
422 x |= x >> 32;
423 return ia64_popcnt(x) - 1;
424}
425
Akinobu Mita2875aef2006-03-26 01:39:25 -0800426#include <asm-generic/bitops/fls64.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427
428/*
Akinobu Mita2875aef2006-03-26 01:39:25 -0800429 * ffs: find first bit set. This is defined the same way as the libc and
430 * compiler builtin ffs routines, therefore differs in spirit from the above
431 * ffz (man ffs): it operates on "int" values only and the result value is the
432 * bit number + 1. ffs(0) is defined to return zero.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 */
434#define ffs(x) __builtin_ffs(x)
435
436/*
437 * hweightN: returns the hamming weight (i.e. the number
438 * of bits set) of a N-bit word
439 */
440static __inline__ unsigned long
441hweight64 (unsigned long x)
442{
443 unsigned long result;
444 result = ia64_popcnt(x);
445 return result;
446}
447
448#define hweight32(x) (unsigned int) hweight64((x) & 0xfffffffful)
449#define hweight16(x) (unsigned int) hweight64((x) & 0xfffful)
450#define hweight8(x) (unsigned int) hweight64((x) & 0xfful)
451
452#endif /* __KERNEL__ */
453
Akinobu Mita2875aef2006-03-26 01:39:25 -0800454#include <asm-generic/bitops/find.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455
456#ifdef __KERNEL__
457
Akinobu Mita2875aef2006-03-26 01:39:25 -0800458#include <asm-generic/bitops/ext2-non-atomic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462
Akinobu Mita2875aef2006-03-26 01:39:25 -0800463#include <asm-generic/bitops/minix.h>
464#include <asm-generic/bitops/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465
466#endif /* __KERNEL__ */
467
468#endif /* _ASM_IA64_BITOPS_H */