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1/* futex.c: futex operations
2 *
3 * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/futex.h>
13#include <linux/uaccess.h>
14#include <asm/futex.h>
15#include <asm/errno.h>
16
17/*
18 * the various futex operations; MMU fault checking is ignored under no-MMU
19 * conditions
20 */
21static inline int atomic_futex_op_xchg_set(int oparg, u32 __user *uaddr, int *_oldval)
22{
23 int oldval, ret;
24
25 asm("0: \n"
26 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
27 " ckeq icc3,cc7 \n"
28 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
29 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
30 "2: cst.p %3,%M0 ,cc3,#1 \n"
31 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
32 " beq icc3,#0,0b \n"
33 " setlos 0,%2 \n"
34 "3: \n"
35 ".subsection 2 \n"
36 "4: setlos %5,%2 \n"
37 " bra 3b \n"
38 ".previous \n"
39 ".section __ex_table,\"a\" \n"
40 " .balign 8 \n"
41 " .long 1b,4b \n"
42 " .long 2b,4b \n"
43 ".previous"
44 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
45 : "3"(oparg), "i"(-EFAULT)
46 : "memory", "cc7", "cc3", "icc3"
47 );
48
49 *_oldval = oldval;
50 return ret;
51}
52
53static inline int atomic_futex_op_xchg_add(int oparg, u32 __user *uaddr, int *_oldval)
54{
55 int oldval, ret;
56
57 asm("0: \n"
58 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
59 " ckeq icc3,cc7 \n"
60 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
61 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
62 " add %1,%3,%3 \n"
63 "2: cst.p %3,%M0 ,cc3,#1 \n"
64 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
65 " beq icc3,#0,0b \n"
66 " setlos 0,%2 \n"
67 "3: \n"
68 ".subsection 2 \n"
69 "4: setlos %5,%2 \n"
70 " bra 3b \n"
71 ".previous \n"
72 ".section __ex_table,\"a\" \n"
73 " .balign 8 \n"
74 " .long 1b,4b \n"
75 " .long 2b,4b \n"
76 ".previous"
77 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
78 : "3"(oparg), "i"(-EFAULT)
79 : "memory", "cc7", "cc3", "icc3"
80 );
81
82 *_oldval = oldval;
83 return ret;
84}
85
86static inline int atomic_futex_op_xchg_or(int oparg, u32 __user *uaddr, int *_oldval)
87{
88 int oldval, ret;
89
90 asm("0: \n"
91 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
92 " ckeq icc3,cc7 \n"
93 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
94 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
95 " or %1,%3,%3 \n"
96 "2: cst.p %3,%M0 ,cc3,#1 \n"
97 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
98 " beq icc3,#0,0b \n"
99 " setlos 0,%2 \n"
100 "3: \n"
101 ".subsection 2 \n"
102 "4: setlos %5,%2 \n"
103 " bra 3b \n"
104 ".previous \n"
105 ".section __ex_table,\"a\" \n"
106 " .balign 8 \n"
107 " .long 1b,4b \n"
108 " .long 2b,4b \n"
109 ".previous"
110 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
111 : "3"(oparg), "i"(-EFAULT)
112 : "memory", "cc7", "cc3", "icc3"
113 );
114
115 *_oldval = oldval;
116 return ret;
117}
118
119static inline int atomic_futex_op_xchg_and(int oparg, u32 __user *uaddr, int *_oldval)
120{
121 int oldval, ret;
122
123 asm("0: \n"
124 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
125 " ckeq icc3,cc7 \n"
126 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
127 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
128 " and %1,%3,%3 \n"
129 "2: cst.p %3,%M0 ,cc3,#1 \n"
130 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
131 " beq icc3,#0,0b \n"
132 " setlos 0,%2 \n"
133 "3: \n"
134 ".subsection 2 \n"
135 "4: setlos %5,%2 \n"
136 " bra 3b \n"
137 ".previous \n"
138 ".section __ex_table,\"a\" \n"
139 " .balign 8 \n"
140 " .long 1b,4b \n"
141 " .long 2b,4b \n"
142 ".previous"
143 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
144 : "3"(oparg), "i"(-EFAULT)
145 : "memory", "cc7", "cc3", "icc3"
146 );
147
148 *_oldval = oldval;
149 return ret;
150}
151
152static inline int atomic_futex_op_xchg_xor(int oparg, u32 __user *uaddr, int *_oldval)
153{
154 int oldval, ret;
155
156 asm("0: \n"
157 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
158 " ckeq icc3,cc7 \n"
159 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
160 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
161 " xor %1,%3,%3 \n"
162 "2: cst.p %3,%M0 ,cc3,#1 \n"
163 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
164 " beq icc3,#0,0b \n"
165 " setlos 0,%2 \n"
166 "3: \n"
167 ".subsection 2 \n"
168 "4: setlos %5,%2 \n"
169 " bra 3b \n"
170 ".previous \n"
171 ".section __ex_table,\"a\" \n"
172 " .balign 8 \n"
173 " .long 1b,4b \n"
174 " .long 2b,4b \n"
175 ".previous"
176 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
177 : "3"(oparg), "i"(-EFAULT)
178 : "memory", "cc7", "cc3", "icc3"
179 );
180
181 *_oldval = oldval;
182 return ret;
183}
184
185/*****************************************************************************/
186/*
187 * do the futex operations
188 */
189int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
190{
191 int op = (encoded_op >> 28) & 7;
192 int cmp = (encoded_op >> 24) & 15;
193 int oparg = (encoded_op << 8) >> 20;
194 int cmparg = (encoded_op << 20) >> 20;
195 int oldval = 0, ret;
196
197 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
198 oparg = 1 << oparg;
199
200 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
201 return -EFAULT;
202
203 pagefault_disable();
204
205 switch (op) {
206 case FUTEX_OP_SET:
207 ret = atomic_futex_op_xchg_set(oparg, uaddr, &oldval);
208 break;
209 case FUTEX_OP_ADD:
210 ret = atomic_futex_op_xchg_add(oparg, uaddr, &oldval);
211 break;
212 case FUTEX_OP_OR:
213 ret = atomic_futex_op_xchg_or(oparg, uaddr, &oldval);
214 break;
215 case FUTEX_OP_ANDN:
216 ret = atomic_futex_op_xchg_and(~oparg, uaddr, &oldval);
217 break;
218 case FUTEX_OP_XOR:
219 ret = atomic_futex_op_xchg_xor(oparg, uaddr, &oldval);
220 break;
221 default:
222 ret = -ENOSYS;
223 break;
224 }
225
226 pagefault_enable();
227
228 if (!ret) {
229 switch (cmp) {
230 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
231 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
232 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
233 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
234 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
235 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
236 default: ret = -ENOSYS; break;
237 }
238 }
239
240 return ret;
241
242} /* end futex_atomic_op_inuser() */
1/* futex.c: futex operations
2 *
3 * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/futex.h>
13#include <linux/uaccess.h>
14#include <asm/futex.h>
15#include <asm/errno.h>
16
17/*
18 * the various futex operations; MMU fault checking is ignored under no-MMU
19 * conditions
20 */
21static inline int atomic_futex_op_xchg_set(int oparg, u32 __user *uaddr, int *_oldval)
22{
23 int oldval, ret;
24
25 asm("0: \n"
26 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
27 " ckeq icc3,cc7 \n"
28 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
29 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
30 "2: cst.p %3,%M0 ,cc3,#1 \n"
31 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
32 " beq icc3,#0,0b \n"
33 " setlos 0,%2 \n"
34 "3: \n"
35 ".subsection 2 \n"
36 "4: setlos %5,%2 \n"
37 " bra 3b \n"
38 ".previous \n"
39 ".section __ex_table,\"a\" \n"
40 " .balign 8 \n"
41 " .long 1b,4b \n"
42 " .long 2b,4b \n"
43 ".previous"
44 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
45 : "3"(oparg), "i"(-EFAULT)
46 : "memory", "cc7", "cc3", "icc3"
47 );
48
49 *_oldval = oldval;
50 return ret;
51}
52
53static inline int atomic_futex_op_xchg_add(int oparg, u32 __user *uaddr, int *_oldval)
54{
55 int oldval, ret;
56
57 asm("0: \n"
58 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
59 " ckeq icc3,cc7 \n"
60 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
61 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
62 " add %1,%3,%3 \n"
63 "2: cst.p %3,%M0 ,cc3,#1 \n"
64 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
65 " beq icc3,#0,0b \n"
66 " setlos 0,%2 \n"
67 "3: \n"
68 ".subsection 2 \n"
69 "4: setlos %5,%2 \n"
70 " bra 3b \n"
71 ".previous \n"
72 ".section __ex_table,\"a\" \n"
73 " .balign 8 \n"
74 " .long 1b,4b \n"
75 " .long 2b,4b \n"
76 ".previous"
77 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
78 : "3"(oparg), "i"(-EFAULT)
79 : "memory", "cc7", "cc3", "icc3"
80 );
81
82 *_oldval = oldval;
83 return ret;
84}
85
86static inline int atomic_futex_op_xchg_or(int oparg, u32 __user *uaddr, int *_oldval)
87{
88 int oldval, ret;
89
90 asm("0: \n"
91 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
92 " ckeq icc3,cc7 \n"
93 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
94 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
95 " or %1,%3,%3 \n"
96 "2: cst.p %3,%M0 ,cc3,#1 \n"
97 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
98 " beq icc3,#0,0b \n"
99 " setlos 0,%2 \n"
100 "3: \n"
101 ".subsection 2 \n"
102 "4: setlos %5,%2 \n"
103 " bra 3b \n"
104 ".previous \n"
105 ".section __ex_table,\"a\" \n"
106 " .balign 8 \n"
107 " .long 1b,4b \n"
108 " .long 2b,4b \n"
109 ".previous"
110 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
111 : "3"(oparg), "i"(-EFAULT)
112 : "memory", "cc7", "cc3", "icc3"
113 );
114
115 *_oldval = oldval;
116 return ret;
117}
118
119static inline int atomic_futex_op_xchg_and(int oparg, u32 __user *uaddr, int *_oldval)
120{
121 int oldval, ret;
122
123 asm("0: \n"
124 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
125 " ckeq icc3,cc7 \n"
126 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
127 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
128 " and %1,%3,%3 \n"
129 "2: cst.p %3,%M0 ,cc3,#1 \n"
130 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
131 " beq icc3,#0,0b \n"
132 " setlos 0,%2 \n"
133 "3: \n"
134 ".subsection 2 \n"
135 "4: setlos %5,%2 \n"
136 " bra 3b \n"
137 ".previous \n"
138 ".section __ex_table,\"a\" \n"
139 " .balign 8 \n"
140 " .long 1b,4b \n"
141 " .long 2b,4b \n"
142 ".previous"
143 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
144 : "3"(oparg), "i"(-EFAULT)
145 : "memory", "cc7", "cc3", "icc3"
146 );
147
148 *_oldval = oldval;
149 return ret;
150}
151
152static inline int atomic_futex_op_xchg_xor(int oparg, u32 __user *uaddr, int *_oldval)
153{
154 int oldval, ret;
155
156 asm("0: \n"
157 " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */
158 " ckeq icc3,cc7 \n"
159 "1: ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */
160 " orcr cc7,cc7,cc3 \n" /* set CC3 to true */
161 " xor %1,%3,%3 \n"
162 "2: cst.p %3,%M0 ,cc3,#1 \n"
163 " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */
164 " beq icc3,#0,0b \n"
165 " setlos 0,%2 \n"
166 "3: \n"
167 ".subsection 2 \n"
168 "4: setlos %5,%2 \n"
169 " bra 3b \n"
170 ".previous \n"
171 ".section __ex_table,\"a\" \n"
172 " .balign 8 \n"
173 " .long 1b,4b \n"
174 " .long 2b,4b \n"
175 ".previous"
176 : "+U"(*uaddr), "=&r"(oldval), "=&r"(ret), "=r"(oparg)
177 : "3"(oparg), "i"(-EFAULT)
178 : "memory", "cc7", "cc3", "icc3"
179 );
180
181 *_oldval = oldval;
182 return ret;
183}
184
185/*****************************************************************************/
186/*
187 * do the futex operations
188 */
189int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
190{
191 int op = (encoded_op >> 28) & 7;
192 int cmp = (encoded_op >> 24) & 15;
193 int oparg = (encoded_op << 8) >> 20;
194 int cmparg = (encoded_op << 20) >> 20;
195 int oldval = 0, ret;
196
197 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
198 oparg = 1 << oparg;
199
200 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
201 return -EFAULT;
202
203 pagefault_disable();
204
205 switch (op) {
206 case FUTEX_OP_SET:
207 ret = atomic_futex_op_xchg_set(oparg, uaddr, &oldval);
208 break;
209 case FUTEX_OP_ADD:
210 ret = atomic_futex_op_xchg_add(oparg, uaddr, &oldval);
211 break;
212 case FUTEX_OP_OR:
213 ret = atomic_futex_op_xchg_or(oparg, uaddr, &oldval);
214 break;
215 case FUTEX_OP_ANDN:
216 ret = atomic_futex_op_xchg_and(~oparg, uaddr, &oldval);
217 break;
218 case FUTEX_OP_XOR:
219 ret = atomic_futex_op_xchg_xor(oparg, uaddr, &oldval);
220 break;
221 default:
222 ret = -ENOSYS;
223 break;
224 }
225
226 pagefault_enable();
227
228 if (!ret) {
229 switch (cmp) {
230 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
231 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
232 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
233 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
234 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
235 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
236 default: ret = -ENOSYS; break;
237 }
238 }
239
240 return ret;
241
242} /* end futex_atomic_op_inuser() */