powerpc/radix: Fix kernel crash with mremap()
[linux-2.6-block.git] / arch / powerpc / include / asm / bitops.h
CommitLineData
a0e60b20
DG
1/*
2 * PowerPC atomic bit operations.
3 *
4 * Merged version by David Gibson <david@gibson.dropbear.id.au>.
5 * Based on ppc64 versions by: Dave Engebretsen, Todd Inglett, Don
6 * Reed, Pat McCarthy, Peter Bergner, Anton Blanchard. They
7 * originally took it from the ppc32 code.
8 *
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 for a
16 * ppc64 system the bits end up numbered:
e7a7a65e 17 * |63..............0|127............64|191...........128|255...........192|
a0e60b20 18 * and on ppc32:
e7a7a65e 19 * |31.....0|63....32|95....64|127...96|159..128|191..160|223..192|255..224|
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DG
20 *
21 * There are a few little-endian macros used mostly for filesystem
22 * bitmaps, these work on similar bit arrays layouts, but
23 * byte-oriented:
24 * |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
25 *
26 * The main difference is that bit 3-5 (64b) or 3-4 (32b) in the bit
27 * number field needs to be reversed compared to the big-endian bit
28 * fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b).
29 *
30 * This program is free software; you can redistribute it and/or
31 * modify it under the terms of the GNU General Public License
32 * as published by the Free Software Foundation; either version
33 * 2 of the License, or (at your option) any later version.
34 */
35
36#ifndef _ASM_POWERPC_BITOPS_H
37#define _ASM_POWERPC_BITOPS_H
38
39#ifdef __KERNEL__
40
0624517d
JS
41#ifndef _LINUX_BITOPS_H
42#error only <linux/bitops.h> can be included directly
43#endif
44
a0e60b20 45#include <linux/compiler.h>
3ddfbcf1 46#include <asm/asm-compat.h>
a0e60b20 47#include <asm/synch.h>
36a7eeaf 48#include <asm/asm-405.h>
a0e60b20 49
e22a2274
MS
50/* PPC bit number conversion */
51#define PPC_BITLSHIFT(be) (BITS_PER_LONG - 1 - (be))
52#define PPC_BIT(bit) (1UL << PPC_BITLSHIFT(bit))
53#define PPC_BITMASK(bs, be) ((PPC_BIT(bs) - PPC_BIT(be)) | PPC_BIT(bs))
54
7b9f71f9
NP
55/* Put a PPC bit into a "normal" bit position */
56#define PPC_BITEXTRACT(bits, ppc_bit, dst_bit) \
57 ((((bits) >> PPC_BITLSHIFT(ppc_bit)) & 1) << (dst_bit))
58
22bd64a6
BH
59#define PPC_BITLSHIFT32(be) (32 - 1 - (be))
60#define PPC_BIT32(bit) (1UL << PPC_BITLSHIFT32(bit))
61#define PPC_BITMASK32(bs, be) ((PPC_BIT32(bs) - PPC_BIT32(be))|PPC_BIT32(bs))
62
63#define PPC_BITLSHIFT8(be) (8 - 1 - (be))
64#define PPC_BIT8(bit) (1UL << PPC_BITLSHIFT8(bit))
65#define PPC_BITMASK8(bs, be) ((PPC_BIT8(bs) - PPC_BIT8(be))|PPC_BIT8(bs))
66
c645073f 67#include <asm/barrier.h>
a0e60b20 68
0d2d3e38 69/* Macro for generating the ***_bits() functions */
576be130 70#define DEFINE_BITOP(fn, op, prefix) \
0d2d3e38
GT
71static __inline__ void fn(unsigned long mask, \
72 volatile unsigned long *_p) \
73{ \
74 unsigned long old; \
75 unsigned long *p = (unsigned long *)_p; \
76 __asm__ __volatile__ ( \
77 prefix \
864b9e6f 78"1:" PPC_LLARX(%0,0,%3,0) "\n" \
0d2d3e38
GT
79 stringify_in_c(op) "%0,%0,%2\n" \
80 PPC405_ERR77(0,%3) \
81 PPC_STLCX "%0,0,%3\n" \
82 "bne- 1b\n" \
0d2d3e38
GT
83 : "=&r" (old), "+m" (*p) \
84 : "r" (mask), "r" (p) \
85 : "cc", "memory"); \
86}
87
576be130
ME
88DEFINE_BITOP(set_bits, or, "")
89DEFINE_BITOP(clear_bits, andc, "")
90DEFINE_BITOP(clear_bits_unlock, andc, PPC_RELEASE_BARRIER)
91DEFINE_BITOP(change_bits, xor, "")
0d2d3e38 92
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93static __inline__ void set_bit(int nr, volatile unsigned long *addr)
94{
2237f4f4 95 set_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
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DG
96}
97
98static __inline__ void clear_bit(int nr, volatile unsigned long *addr)
99{
2237f4f4 100 clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
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101}
102
66ffb04c
NP
103static __inline__ void clear_bit_unlock(int nr, volatile unsigned long *addr)
104{
2237f4f4 105 clear_bits_unlock(BIT_MASK(nr), addr + BIT_WORD(nr));
66ffb04c
NP
106}
107
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108static __inline__ void change_bit(int nr, volatile unsigned long *addr)
109{
2237f4f4 110 change_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
0d2d3e38 111}
a0e60b20 112
0d2d3e38
GT
113/* Like DEFINE_BITOP(), with changes to the arguments to 'op' and the output
114 * operands. */
864b9e6f
AB
115#define DEFINE_TESTOP(fn, op, prefix, postfix, eh) \
116static __inline__ unsigned long fn( \
117 unsigned long mask, \
118 volatile unsigned long *_p) \
119{ \
120 unsigned long old, t; \
121 unsigned long *p = (unsigned long *)_p; \
122 __asm__ __volatile__ ( \
123 prefix \
124"1:" PPC_LLARX(%0,0,%3,eh) "\n" \
125 stringify_in_c(op) "%1,%0,%2\n" \
126 PPC405_ERR77(0,%3) \
127 PPC_STLCX "%1,0,%3\n" \
128 "bne- 1b\n" \
129 postfix \
130 : "=&r" (old), "=&r" (t) \
131 : "r" (mask), "r" (p) \
132 : "cc", "memory"); \
133 return (old & mask); \
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134}
135
b97021f8
BH
136DEFINE_TESTOP(test_and_set_bits, or, PPC_ATOMIC_ENTRY_BARRIER,
137 PPC_ATOMIC_EXIT_BARRIER, 0)
f10e2e5b
AB
138DEFINE_TESTOP(test_and_set_bits_lock, or, "",
139 PPC_ACQUIRE_BARRIER, 1)
b97021f8
BH
140DEFINE_TESTOP(test_and_clear_bits, andc, PPC_ATOMIC_ENTRY_BARRIER,
141 PPC_ATOMIC_EXIT_BARRIER, 0)
142DEFINE_TESTOP(test_and_change_bits, xor, PPC_ATOMIC_ENTRY_BARRIER,
143 PPC_ATOMIC_EXIT_BARRIER, 0)
0d2d3e38 144
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DG
145static __inline__ int test_and_set_bit(unsigned long nr,
146 volatile unsigned long *addr)
147{
2237f4f4 148 return test_and_set_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
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DG
149}
150
66ffb04c
NP
151static __inline__ int test_and_set_bit_lock(unsigned long nr,
152 volatile unsigned long *addr)
153{
2237f4f4
AM
154 return test_and_set_bits_lock(BIT_MASK(nr),
155 addr + BIT_WORD(nr)) != 0;
66ffb04c
NP
156}
157
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DG
158static __inline__ int test_and_clear_bit(unsigned long nr,
159 volatile unsigned long *addr)
160{
2237f4f4 161 return test_and_clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
a0e60b20
DG
162}
163
164static __inline__ int test_and_change_bit(unsigned long nr,
165 volatile unsigned long *addr)
166{
2237f4f4 167 return test_and_change_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
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DG
168}
169
d11914b2
NP
170#ifdef CONFIG_PPC64
171static __inline__ unsigned long clear_bit_unlock_return_word(int nr,
172 volatile unsigned long *addr)
173{
174 unsigned long old, t;
175 unsigned long *p = (unsigned long *)addr + BIT_WORD(nr);
176 unsigned long mask = BIT_MASK(nr);
177
178 __asm__ __volatile__ (
179 PPC_RELEASE_BARRIER
180"1:" PPC_LLARX(%0,0,%3,0) "\n"
181 "andc %1,%0,%2\n"
182 PPC405_ERR77(0,%3)
183 PPC_STLCX "%1,0,%3\n"
184 "bne- 1b\n"
185 : "=&r" (old), "=&r" (t)
186 : "r" (mask), "r" (p)
187 : "cc", "memory");
188
189 return old;
190}
191
192/* This is a special function for mm/filemap.c */
193#define clear_bit_unlock_is_negative_byte(nr, addr) \
194 (clear_bit_unlock_return_word(nr, addr) & BIT_MASK(PG_waiters))
195
196#endif /* CONFIG_PPC64 */
197
e779b2f9 198#include <asm-generic/bitops/non-atomic.h>
a0e60b20 199
66ffb04c
NP
200static __inline__ void __clear_bit_unlock(int nr, volatile unsigned long *addr)
201{
f10e2e5b 202 __asm__ __volatile__(PPC_RELEASE_BARRIER "" ::: "memory");
66ffb04c
NP
203 __clear_bit(nr, addr);
204}
205
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206/*
207 * Return the zero-based bit position (LE, not IBM bit numbering) of
208 * the most significant 1-bit in a double word.
209 */
f782ddf2 210#define __ilog2(x) ilog2(x)
ef55d53c 211
22ef33b3 212#include <asm-generic/bitops/ffz.h>
a0e60b20 213
f83647d6 214#include <asm-generic/bitops/builtin-__ffs.h>
a0e60b20 215
f83647d6 216#include <asm-generic/bitops/builtin-ffs.h>
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217
218/*
219 * fls: find last (most-significant) bit set.
220 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
221 */
222static __inline__ int fls(unsigned int x)
223{
2fcff790 224 return 32 - __builtin_clz(x);
a0e60b20 225}
9f264be6 226
2fcff790 227#include <asm-generic/bitops/builtin-__fls.h>
56a6b1eb 228
9f264be6
PM
229static __inline__ int fls64(__u64 x)
230{
2fcff790 231 return 64 - __builtin_clzll(x);
9f264be6 232}
9f264be6 233
64ff3128
AB
234#ifdef CONFIG_PPC64
235unsigned int __arch_hweight8(unsigned int w);
236unsigned int __arch_hweight16(unsigned int w);
237unsigned int __arch_hweight32(unsigned int w);
238unsigned long __arch_hweight64(__u64 w);
239#include <asm-generic/bitops/const_hweight.h>
240#else
e779b2f9 241#include <asm-generic/bitops/hweight.h>
64ff3128
AB
242#endif
243
47b9d9bd 244#include <asm-generic/bitops/find.h>
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245
246/* Little-endian versions */
79597be9 247#include <asm-generic/bitops/le.h>
a0e60b20 248
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249/* Bitmap functions for the ext2 filesystem */
250
148817ba 251#include <asm-generic/bitops/ext2-atomic-setbit.h>
a0e60b20 252
e779b2f9 253#include <asm-generic/bitops/sched.h>
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254
255#endif /* __KERNEL__ */
256
257#endif /* _ASM_POWERPC_BITOPS_H */