diff options
Diffstat (limited to 'include/asm-i386')
-rw-r--r-- | include/asm-i386/sync_bitops.h | 156 | ||||
-rw-r--r-- | include/asm-i386/system.h | 36 |
2 files changed, 192 insertions, 0 deletions
diff --git a/include/asm-i386/sync_bitops.h b/include/asm-i386/sync_bitops.h new file mode 100644 index 000000000000..c94d51c993ee --- /dev/null +++ b/include/asm-i386/sync_bitops.h | |||
@@ -0,0 +1,156 @@ | |||
1 | #ifndef _I386_SYNC_BITOPS_H | ||
2 | #define _I386_SYNC_BITOPS_H | ||
3 | |||
4 | /* | ||
5 | * Copyright 1992, Linus Torvalds. | ||
6 | */ | ||
7 | |||
8 | /* | ||
9 | * These have to be done with inline assembly: that way the bit-setting | ||
10 | * is guaranteed to be atomic. All bit operations return 0 if the bit | ||
11 | * was cleared before the operation and != 0 if it was not. | ||
12 | * | ||
13 | * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). | ||
14 | */ | ||
15 | |||
16 | #define ADDR (*(volatile long *) addr) | ||
17 | |||
18 | /** | ||
19 | * sync_set_bit - Atomically set a bit in memory | ||
20 | * @nr: the bit to set | ||
21 | * @addr: the address to start counting from | ||
22 | * | ||
23 | * This function is atomic and may not be reordered. See __set_bit() | ||
24 | * if you do not require the atomic guarantees. | ||
25 | * | ||
26 | * Note: there are no guarantees that this function will not be reordered | ||
27 | * on non x86 architectures, so if you are writting portable code, | ||
28 | * make sure not to rely on its reordering guarantees. | ||
29 | * | ||
30 | * Note that @nr may be almost arbitrarily large; this function is not | ||
31 | * restricted to acting on a single-word quantity. | ||
32 | */ | ||
33 | static inline void sync_set_bit(int nr, volatile unsigned long * addr) | ||
34 | { | ||
35 | __asm__ __volatile__("lock; btsl %1,%0" | ||
36 | :"+m" (ADDR) | ||
37 | :"Ir" (nr) | ||
38 | : "memory"); | ||
39 | } | ||
40 | |||
41 | /** | ||
42 | * sync_clear_bit - Clears a bit in memory | ||
43 | * @nr: Bit to clear | ||
44 | * @addr: Address to start counting from | ||
45 | * | ||
46 | * sync_clear_bit() is atomic and may not be reordered. However, it does | ||
47 | * not contain a memory barrier, so if it is used for locking purposes, | ||
48 | * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() | ||
49 | * in order to ensure changes are visible on other processors. | ||
50 | */ | ||
51 | static inline void sync_clear_bit(int nr, volatile unsigned long * addr) | ||
52 | { | ||
53 | __asm__ __volatile__("lock; btrl %1,%0" | ||
54 | :"+m" (ADDR) | ||
55 | :"Ir" (nr) | ||
56 | : "memory"); | ||
57 | } | ||
58 | |||
59 | /** | ||
60 | * sync_change_bit - Toggle a bit in memory | ||
61 | * @nr: Bit to change | ||
62 | * @addr: Address to start counting from | ||
63 | * | ||
64 | * change_bit() is atomic and may not be reordered. It may be | ||
65 | * reordered on other architectures than x86. | ||
66 | * Note that @nr may be almost arbitrarily large; this function is not | ||
67 | * restricted to acting on a single-word quantity. | ||
68 | */ | ||
69 | static inline void sync_change_bit(int nr, volatile unsigned long * addr) | ||
70 | { | ||
71 | __asm__ __volatile__("lock; btcl %1,%0" | ||
72 | :"+m" (ADDR) | ||
73 | :"Ir" (nr) | ||
74 | : "memory"); | ||
75 | } | ||
76 | |||
77 | /** | ||
78 | * sync_test_and_set_bit - Set a bit and return its old value | ||
79 | * @nr: Bit to set | ||
80 | * @addr: Address to count from | ||
81 | * | ||
82 | * This operation is atomic and cannot be reordered. | ||
83 | * It may be reordered on other architectures than x86. | ||
84 | * It also implies a memory barrier. | ||
85 | */ | ||
86 | static inline int sync_test_and_set_bit(int nr, volatile unsigned long * addr) | ||
87 | { | ||
88 | int oldbit; | ||
89 | |||
90 | __asm__ __volatile__("lock; btsl %2,%1\n\tsbbl %0,%0" | ||
91 | :"=r" (oldbit),"+m" (ADDR) | ||
92 | :"Ir" (nr) : "memory"); | ||
93 | return oldbit; | ||
94 | } | ||
95 | |||
96 | /** | ||
97 | * sync_test_and_clear_bit - Clear a bit and return its old value | ||
98 | * @nr: Bit to clear | ||
99 | * @addr: Address to count from | ||
100 | * | ||
101 | * This operation is atomic and cannot be reordered. | ||
102 | * It can be reorderdered on other architectures other than x86. | ||
103 | * It also implies a memory barrier. | ||
104 | */ | ||
105 | static inline int sync_test_and_clear_bit(int nr, volatile unsigned long * addr) | ||
106 | { | ||
107 | int oldbit; | ||
108 | |||
109 | __asm__ __volatile__("lock; btrl %2,%1\n\tsbbl %0,%0" | ||
110 | :"=r" (oldbit),"+m" (ADDR) | ||
111 | :"Ir" (nr) : "memory"); | ||
112 | return oldbit; | ||
113 | } | ||
114 | |||
115 | /** | ||
116 | * sync_test_and_change_bit - Change a bit and return its old value | ||
117 | * @nr: Bit to change | ||
118 | * @addr: Address to count from | ||
119 | * | ||
120 | * This operation is atomic and cannot be reordered. | ||
121 | * It also implies a memory barrier. | ||
122 | */ | ||
123 | static inline int sync_test_and_change_bit(int nr, volatile unsigned long* addr) | ||
124 | { | ||
125 | int oldbit; | ||
126 | |||
127 | __asm__ __volatile__("lock; btcl %2,%1\n\tsbbl %0,%0" | ||
128 | :"=r" (oldbit),"+m" (ADDR) | ||
129 | :"Ir" (nr) : "memory"); | ||
130 | return oldbit; | ||
131 | } | ||
132 | |||
133 | static __always_inline int sync_const_test_bit(int nr, const volatile unsigned long *addr) | ||
134 | { | ||
135 | return ((1UL << (nr & 31)) & | ||
136 | (((const volatile unsigned int *)addr)[nr >> 5])) != 0; | ||
137 | } | ||
138 | |||
139 | static inline int sync_var_test_bit(int nr, const volatile unsigned long * addr) | ||
140 | { | ||
141 | int oldbit; | ||
142 | |||
143 | __asm__ __volatile__("btl %2,%1\n\tsbbl %0,%0" | ||
144 | :"=r" (oldbit) | ||
145 | :"m" (ADDR),"Ir" (nr)); | ||
146 | return oldbit; | ||
147 | } | ||
148 | |||
149 | #define sync_test_bit(nr,addr) \ | ||
150 | (__builtin_constant_p(nr) ? \ | ||
151 | sync_constant_test_bit((nr),(addr)) : \ | ||
152 | sync_var_test_bit((nr),(addr))) | ||
153 | |||
154 | #undef ADDR | ||
155 | |||
156 | #endif /* _I386_SYNC_BITOPS_H */ | ||
diff --git a/include/asm-i386/system.h b/include/asm-i386/system.h index 098bcee94e38..a6dabbcd6e6a 100644 --- a/include/asm-i386/system.h +++ b/include/asm-i386/system.h | |||
@@ -267,6 +267,9 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz | |||
267 | #define cmpxchg(ptr,o,n)\ | 267 | #define cmpxchg(ptr,o,n)\ |
268 | ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ | 268 | ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ |
269 | (unsigned long)(n),sizeof(*(ptr)))) | 269 | (unsigned long)(n),sizeof(*(ptr)))) |
270 | #define sync_cmpxchg(ptr,o,n)\ | ||
271 | ((__typeof__(*(ptr)))__sync_cmpxchg((ptr),(unsigned long)(o),\ | ||
272 | (unsigned long)(n),sizeof(*(ptr)))) | ||
270 | #endif | 273 | #endif |
271 | 274 | ||
272 | static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, | 275 | static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, |
@@ -296,6 +299,39 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, | |||
296 | return old; | 299 | return old; |
297 | } | 300 | } |
298 | 301 | ||
302 | /* | ||
303 | * Always use locked operations when touching memory shared with a | ||
304 | * hypervisor, since the system may be SMP even if the guest kernel | ||
305 | * isn't. | ||
306 | */ | ||
307 | static inline unsigned long __sync_cmpxchg(volatile void *ptr, | ||
308 | unsigned long old, | ||
309 | unsigned long new, int size) | ||
310 | { | ||
311 | unsigned long prev; | ||
312 | switch (size) { | ||
313 | case 1: | ||
314 | __asm__ __volatile__("lock; cmpxchgb %b1,%2" | ||
315 | : "=a"(prev) | ||
316 | : "q"(new), "m"(*__xg(ptr)), "0"(old) | ||
317 | : "memory"); | ||
318 | return prev; | ||
319 | case 2: | ||
320 | __asm__ __volatile__("lock; cmpxchgw %w1,%2" | ||
321 | : "=a"(prev) | ||
322 | : "r"(new), "m"(*__xg(ptr)), "0"(old) | ||
323 | : "memory"); | ||
324 | return prev; | ||
325 | case 4: | ||
326 | __asm__ __volatile__("lock; cmpxchgl %1,%2" | ||
327 | : "=a"(prev) | ||
328 | : "r"(new), "m"(*__xg(ptr)), "0"(old) | ||
329 | : "memory"); | ||
330 | return prev; | ||
331 | } | ||
332 | return old; | ||
333 | } | ||
334 | |||
299 | #ifndef CONFIG_X86_CMPXCHG | 335 | #ifndef CONFIG_X86_CMPXCHG |
300 | /* | 336 | /* |
301 | * Building a kernel capable running on 80386. It may be necessary to | 337 | * Building a kernel capable running on 80386. It may be necessary to |