aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-x86/bitops_32.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/asm-x86/bitops_32.h')
-rw-r--r--include/asm-x86/bitops_32.h324
1 files changed, 8 insertions, 316 deletions
diff --git a/include/asm-x86/bitops_32.h b/include/asm-x86/bitops_32.h
index 0b40f6d20be..e4d75fcf9c0 100644
--- a/include/asm-x86/bitops_32.h
+++ b/include/asm-x86/bitops_32.h
@@ -5,320 +5,12 @@
5 * Copyright 1992, Linus Torvalds. 5 * Copyright 1992, Linus Torvalds.
6 */ 6 */
7 7
8#ifndef _LINUX_BITOPS_H
9#error only <linux/bitops.h> can be included directly
10#endif
11
12#include <linux/compiler.h>
13#include <asm/alternative.h>
14
15/*
16 * These have to be done with inline assembly: that way the bit-setting
17 * is guaranteed to be atomic. All bit operations return 0 if the bit
18 * was cleared before the operation and != 0 if it was not.
19 *
20 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
21 */
22
23#define ADDR (*(volatile long *) addr)
24
25/**
26 * set_bit - Atomically set a bit in memory
27 * @nr: the bit to set
28 * @addr: the address to start counting from
29 *
30 * This function is atomic and may not be reordered. See __set_bit()
31 * if you do not require the atomic guarantees.
32 *
33 * Note: there are no guarantees that this function will not be reordered
34 * on non x86 architectures, so if you are writing portable code,
35 * make sure not to rely on its reordering guarantees.
36 *
37 * Note that @nr may be almost arbitrarily large; this function is not
38 * restricted to acting on a single-word quantity.
39 */
40static inline void set_bit(int nr, volatile unsigned long * addr)
41{
42 __asm__ __volatile__( LOCK_PREFIX
43 "btsl %1,%0"
44 :"+m" (ADDR)
45 :"Ir" (nr));
46}
47
48/**
49 * __set_bit - Set a bit in memory
50 * @nr: the bit to set
51 * @addr: the address to start counting from
52 *
53 * Unlike set_bit(), this function is non-atomic and may be reordered.
54 * If it's called on the same region of memory simultaneously, the effect
55 * may be that only one operation succeeds.
56 */
57static inline void __set_bit(int nr, volatile unsigned long * addr)
58{
59 __asm__(
60 "btsl %1,%0"
61 :"+m" (ADDR)
62 :"Ir" (nr));
63}
64
65/**
66 * clear_bit - Clears a bit in memory
67 * @nr: Bit to clear
68 * @addr: Address to start counting from
69 *
70 * clear_bit() is atomic and may not be reordered. However, it does
71 * not contain a memory barrier, so if it is used for locking purposes,
72 * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
73 * in order to ensure changes are visible on other processors.
74 */
75static inline void clear_bit(int nr, volatile unsigned long * addr)
76{
77 __asm__ __volatile__( LOCK_PREFIX
78 "btrl %1,%0"
79 :"+m" (ADDR)
80 :"Ir" (nr));
81}
82
83/*
84 * clear_bit_unlock - Clears a bit in memory
85 * @nr: Bit to clear
86 * @addr: Address to start counting from
87 *
88 * clear_bit() is atomic and implies release semantics before the memory
89 * operation. It can be used for an unlock.
90 */
91static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
92{
93 barrier();
94 clear_bit(nr, addr);
95}
96
97static inline void __clear_bit(int nr, volatile unsigned long * addr)
98{
99 __asm__ __volatile__(
100 "btrl %1,%0"
101 :"+m" (ADDR)
102 :"Ir" (nr));
103}
104
105/*
106 * __clear_bit_unlock - Clears a bit in memory
107 * @nr: Bit to clear
108 * @addr: Address to start counting from
109 *
110 * __clear_bit() is non-atomic and implies release semantics before the memory
111 * operation. It can be used for an unlock if no other CPUs can concurrently
112 * modify other bits in the word.
113 *
114 * No memory barrier is required here, because x86 cannot reorder stores past
115 * older loads. Same principle as spin_unlock.
116 */
117static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
118{
119 barrier();
120 __clear_bit(nr, addr);
121}
122
123#define smp_mb__before_clear_bit() barrier()
124#define smp_mb__after_clear_bit() barrier()
125
126/**
127 * __change_bit - Toggle a bit in memory
128 * @nr: the bit to change
129 * @addr: the address to start counting from
130 *
131 * Unlike change_bit(), this function is non-atomic and may be reordered.
132 * If it's called on the same region of memory simultaneously, the effect
133 * may be that only one operation succeeds.
134 */
135static inline void __change_bit(int nr, volatile unsigned long * addr)
136{
137 __asm__ __volatile__(
138 "btcl %1,%0"
139 :"+m" (ADDR)
140 :"Ir" (nr));
141}
142
143/**
144 * change_bit - Toggle a bit in memory
145 * @nr: Bit to change
146 * @addr: Address to start counting from
147 *
148 * change_bit() is atomic and may not be reordered. It may be
149 * reordered on other architectures than x86.
150 * Note that @nr may be almost arbitrarily large; this function is not
151 * restricted to acting on a single-word quantity.
152 */
153static inline void change_bit(int nr, volatile unsigned long * addr)
154{
155 __asm__ __volatile__( LOCK_PREFIX
156 "btcl %1,%0"
157 :"+m" (ADDR)
158 :"Ir" (nr));
159}
160
161/**
162 * test_and_set_bit - Set a bit and return its old value
163 * @nr: Bit to set
164 * @addr: Address to count from
165 *
166 * This operation is atomic and cannot be reordered.
167 * It may be reordered on other architectures than x86.
168 * It also implies a memory barrier.
169 */
170static inline int test_and_set_bit(int nr, volatile unsigned long * addr)
171{
172 int oldbit;
173
174 __asm__ __volatile__( LOCK_PREFIX
175 "btsl %2,%1\n\tsbbl %0,%0"
176 :"=r" (oldbit),"+m" (ADDR)
177 :"Ir" (nr) : "memory");
178 return oldbit;
179}
180
181/**
182 * test_and_set_bit_lock - Set a bit and return its old value for lock
183 * @nr: Bit to set
184 * @addr: Address to count from
185 *
186 * This is the same as test_and_set_bit on x86.
187 */
188static inline int test_and_set_bit_lock(int nr, volatile unsigned long *addr)
189{
190 return test_and_set_bit(nr, addr);
191}
192
193/**
194 * __test_and_set_bit - Set a bit and return its old value
195 * @nr: Bit to set
196 * @addr: Address to count from
197 *
198 * This operation is non-atomic and can be reordered.
199 * If two examples of this operation race, one can appear to succeed
200 * but actually fail. You must protect multiple accesses with a lock.
201 */
202static inline int __test_and_set_bit(int nr, volatile unsigned long * addr)
203{
204 int oldbit;
205
206 __asm__(
207 "btsl %2,%1\n\tsbbl %0,%0"
208 :"=r" (oldbit),"+m" (ADDR)
209 :"Ir" (nr));
210 return oldbit;
211}
212
213/**
214 * test_and_clear_bit - Clear a bit and return its old value
215 * @nr: Bit to clear
216 * @addr: Address to count from
217 *
218 * This operation is atomic and cannot be reordered.
219 * It can be reorderdered on other architectures other than x86.
220 * It also implies a memory barrier.
221 */
222static inline int test_and_clear_bit(int nr, volatile unsigned long * addr)
223{
224 int oldbit;
225
226 __asm__ __volatile__( LOCK_PREFIX
227 "btrl %2,%1\n\tsbbl %0,%0"
228 :"=r" (oldbit),"+m" (ADDR)
229 :"Ir" (nr) : "memory");
230 return oldbit;
231}
232
233/**
234 * __test_and_clear_bit - Clear a bit and return its old value
235 * @nr: Bit to clear
236 * @addr: Address to count from
237 *
238 * This operation is non-atomic and can be reordered.
239 * If two examples of this operation race, one can appear to succeed
240 * but actually fail. You must protect multiple accesses with a lock.
241 */
242static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
243{
244 int oldbit;
245
246 __asm__(
247 "btrl %2,%1\n\tsbbl %0,%0"
248 :"=r" (oldbit),"+m" (ADDR)
249 :"Ir" (nr));
250 return oldbit;
251}
252
253/* WARNING: non atomic and it can be reordered! */
254static inline int __test_and_change_bit(int nr, volatile unsigned long *addr)
255{
256 int oldbit;
257
258 __asm__ __volatile__(
259 "btcl %2,%1\n\tsbbl %0,%0"
260 :"=r" (oldbit),"+m" (ADDR)
261 :"Ir" (nr) : "memory");
262 return oldbit;
263}
264
265/**
266 * test_and_change_bit - Change a bit and return its old value
267 * @nr: Bit to change
268 * @addr: Address to count from
269 *
270 * This operation is atomic and cannot be reordered.
271 * It also implies a memory barrier.
272 */
273static inline int test_and_change_bit(int nr, volatile unsigned long* addr)
274{
275 int oldbit;
276
277 __asm__ __volatile__( LOCK_PREFIX
278 "btcl %2,%1\n\tsbbl %0,%0"
279 :"=r" (oldbit),"+m" (ADDR)
280 :"Ir" (nr) : "memory");
281 return oldbit;
282}
283
284#if 0 /* Fool kernel-doc since it doesn't do macros yet */
285/**
286 * test_bit - Determine whether a bit is set
287 * @nr: bit number to test
288 * @addr: Address to start counting from
289 */
290static int test_bit(int nr, const volatile void * addr);
291#endif
292
293static __always_inline int constant_test_bit(int nr, const volatile unsigned long *addr)
294{
295 return ((1UL << (nr & 31)) & (addr[nr >> 5])) != 0;
296}
297
298static inline int variable_test_bit(int nr, const volatile unsigned long * addr)
299{
300 int oldbit;
301
302 __asm__ __volatile__(
303 "btl %2,%1\n\tsbbl %0,%0"
304 :"=r" (oldbit)
305 :"m" (ADDR),"Ir" (nr));
306 return oldbit;
307}
308
309#define test_bit(nr,addr) \
310(__builtin_constant_p(nr) ? \
311 constant_test_bit((nr),(addr)) : \
312 variable_test_bit((nr),(addr)))
313
314#undef ADDR
315
316/** 8/**
317 * find_first_zero_bit - find the first zero bit in a memory region 9 * find_first_zero_bit - find the first zero bit in a memory region
318 * @addr: The address to start the search at 10 * @addr: The address to start the search at
319 * @size: The maximum size to search 11 * @size: The maximum size to search
320 * 12 *
321 * Returns the bit-number of the first zero bit, not the number of the byte 13 * Returns the bit number of the first zero bit, not the number of the byte
322 * containing a bit. 14 * containing a bit.
323 */ 15 */
324static inline int find_first_zero_bit(const unsigned long *addr, unsigned size) 16static inline int find_first_zero_bit(const unsigned long *addr, unsigned size)
@@ -348,7 +40,7 @@ static inline int find_first_zero_bit(const unsigned long *addr, unsigned size)
348/** 40/**
349 * find_next_zero_bit - find the first zero bit in a memory region 41 * find_next_zero_bit - find the first zero bit in a memory region
350 * @addr: The address to base the search on 42 * @addr: The address to base the search on
351 * @offset: The bitnumber to start searching at 43 * @offset: The bit number to start searching at
352 * @size: The maximum size to search 44 * @size: The maximum size to search
353 */ 45 */
354int find_next_zero_bit(const unsigned long *addr, int size, int offset); 46int find_next_zero_bit(const unsigned long *addr, int size, int offset);
@@ -372,7 +64,7 @@ static inline unsigned long __ffs(unsigned long word)
372 * @addr: The address to start the search at 64 * @addr: The address to start the search at
373 * @size: The maximum size to search 65 * @size: The maximum size to search
374 * 66 *
375 * Returns the bit-number of the first set bit, not the number of the byte 67 * Returns the bit number of the first set bit, not the number of the byte
376 * containing a bit. 68 * containing a bit.
377 */ 69 */
378static inline unsigned find_first_bit(const unsigned long *addr, unsigned size) 70static inline unsigned find_first_bit(const unsigned long *addr, unsigned size)
@@ -391,7 +83,7 @@ static inline unsigned find_first_bit(const unsigned long *addr, unsigned size)
391/** 83/**
392 * find_next_bit - find the first set bit in a memory region 84 * find_next_bit - find the first set bit in a memory region
393 * @addr: The address to base the search on 85 * @addr: The address to base the search on
394 * @offset: The bitnumber to start searching at 86 * @offset: The bit number to start searching at
395 * @size: The maximum size to search 87 * @size: The maximum size to search
396 */ 88 */
397int find_next_bit(const unsigned long *addr, int size, int offset); 89int find_next_bit(const unsigned long *addr, int size, int offset);
@@ -460,10 +152,10 @@ static inline int fls(int x)
460 152
461#include <asm-generic/bitops/ext2-non-atomic.h> 153#include <asm-generic/bitops/ext2-non-atomic.h>
462 154
463#define ext2_set_bit_atomic(lock,nr,addr) \ 155#define ext2_set_bit_atomic(lock, nr, addr) \
464 test_and_set_bit((nr),(unsigned long*)addr) 156 test_and_set_bit((nr), (unsigned long *)addr)
465#define ext2_clear_bit_atomic(lock,nr, addr) \ 157#define ext2_clear_bit_atomic(lock, nr, addr) \
466 test_and_clear_bit((nr),(unsigned long*)addr) 158 test_and_clear_bit((nr), (unsigned long *)addr)
467 159
468#include <asm-generic/bitops/minix.h> 160#include <asm-generic/bitops/minix.h>
469 161