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-rw-r--r--arch/x86/lib/bitops_64.c175
1 files changed, 0 insertions, 175 deletions
diff --git a/arch/x86/lib/bitops_64.c b/arch/x86/lib/bitops_64.c
deleted file mode 100644
index 0e8f491e6ccc..000000000000
--- a/arch/x86/lib/bitops_64.c
+++ /dev/null
@@ -1,175 +0,0 @@
1#include <linux/bitops.h>
2
3#undef find_first_zero_bit
4#undef find_next_zero_bit
5#undef find_first_bit
6#undef find_next_bit
7
8static inline long
9__find_first_zero_bit(const unsigned long * addr, unsigned long size)
10{
11 long d0, d1, d2;
12 long res;
13
14 /*
15 * We must test the size in words, not in bits, because
16 * otherwise incoming sizes in the range -63..-1 will not run
17 * any scasq instructions, and then the flags used by the je
18 * instruction will have whatever random value was in place
19 * before. Nobody should call us like that, but
20 * find_next_zero_bit() does when offset and size are at the
21 * same word and it fails to find a zero itself.
22 */
23 size += 63;
24 size >>= 6;
25 if (!size)
26 return 0;
27 asm volatile(
28 " repe; scasq\n"
29 " je 1f\n"
30 " xorq -8(%%rdi),%%rax\n"
31 " subq $8,%%rdi\n"
32 " bsfq %%rax,%%rdx\n"
33 "1: subq %[addr],%%rdi\n"
34 " shlq $3,%%rdi\n"
35 " addq %%rdi,%%rdx"
36 :"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
37 :"0" (0ULL), "1" (size), "2" (addr), "3" (-1ULL),
38 [addr] "S" (addr) : "memory");
39 /*
40 * Any register would do for [addr] above, but GCC tends to
41 * prefer rbx over rsi, even though rsi is readily available
42 * and doesn't have to be saved.
43 */
44 return res;
45}
46
47/**
48 * find_first_zero_bit - find the first zero bit in a memory region
49 * @addr: The address to start the search at
50 * @size: The maximum size to search
51 *
52 * Returns the bit-number of the first zero bit, not the number of the byte
53 * containing a bit.
54 */
55long find_first_zero_bit(const unsigned long * addr, unsigned long size)
56{
57 return __find_first_zero_bit (addr, size);
58}
59
60/**
61 * find_next_zero_bit - find the next zero bit in a memory region
62 * @addr: The address to base the search on
63 * @offset: The bitnumber to start searching at
64 * @size: The maximum size to search
65 */
66long find_next_zero_bit (const unsigned long * addr, long size, long offset)
67{
68 const unsigned long * p = addr + (offset >> 6);
69 unsigned long set = 0;
70 unsigned long res, bit = offset&63;
71
72 if (bit) {
73 /*
74 * Look for zero in first word
75 */
76 asm("bsfq %1,%0\n\t"
77 "cmoveq %2,%0"
78 : "=r" (set)
79 : "r" (~(*p >> bit)), "r"(64L));
80 if (set < (64 - bit))
81 return set + offset;
82 set = 64 - bit;
83 p++;
84 }
85 /*
86 * No zero yet, search remaining full words for a zero
87 */
88 res = __find_first_zero_bit (p, size - 64 * (p - addr));
89
90 return (offset + set + res);
91}
92
93static inline long
94__find_first_bit(const unsigned long * addr, unsigned long size)
95{
96 long d0, d1;
97 long res;
98
99 /*
100 * We must test the size in words, not in bits, because
101 * otherwise incoming sizes in the range -63..-1 will not run
102 * any scasq instructions, and then the flags used by the jz
103 * instruction will have whatever random value was in place
104 * before. Nobody should call us like that, but
105 * find_next_bit() does when offset and size are at the same
106 * word and it fails to find a one itself.
107 */
108 size += 63;
109 size >>= 6;
110 if (!size)
111 return 0;
112 asm volatile(
113 " repe; scasq\n"
114 " jz 1f\n"
115 " subq $8,%%rdi\n"
116 " bsfq (%%rdi),%%rax\n"
117 "1: subq %[addr],%%rdi\n"
118 " shlq $3,%%rdi\n"
119 " addq %%rdi,%%rax"
120 :"=a" (res), "=&c" (d0), "=&D" (d1)
121 :"0" (0ULL), "1" (size), "2" (addr),
122 [addr] "r" (addr) : "memory");
123 return res;
124}
125
126/**
127 * find_first_bit - find the first set bit in a memory region
128 * @addr: The address to start the search at
129 * @size: The maximum size to search
130 *
131 * Returns the bit-number of the first set bit, not the number of the byte
132 * containing a bit.
133 */
134long find_first_bit(const unsigned long * addr, unsigned long size)
135{
136 return __find_first_bit(addr,size);
137}
138
139/**
140 * find_next_bit - find the first set bit in a memory region
141 * @addr: The address to base the search on
142 * @offset: The bitnumber to start searching at
143 * @size: The maximum size to search
144 */
145long find_next_bit(const unsigned long * addr, long size, long offset)
146{
147 const unsigned long * p = addr + (offset >> 6);
148 unsigned long set = 0, bit = offset & 63, res;
149
150 if (bit) {
151 /*
152 * Look for nonzero in the first 64 bits:
153 */
154 asm("bsfq %1,%0\n\t"
155 "cmoveq %2,%0\n\t"
156 : "=r" (set)
157 : "r" (*p >> bit), "r" (64L));
158 if (set < (64 - bit))
159 return set + offset;
160 set = 64 - bit;
161 p++;
162 }
163 /*
164 * No set bit yet, search remaining full words for a bit
165 */
166 res = __find_first_bit (p, size - 64 * (p - addr));
167 return (offset + set + res);
168}
169
170#include <linux/module.h>
171
172EXPORT_SYMBOL(find_next_bit);
173EXPORT_SYMBOL(find_first_bit);
174EXPORT_SYMBOL(find_first_zero_bit);
175EXPORT_SYMBOL(find_next_zero_bit);
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