]>
git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - arch/arm64/include/asm/futex.h
f32b42e8725dc6d95a884cfffbe3e8fe6134d5d8
2 * Copyright (C) 2012 ARM Ltd.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include <linux/futex.h>
22 #include <linux/uaccess.h>
24 #include <asm/errno.h>
26 #define __futex_atomic_op(insn, ret, oldval, uaddr, tmp, oparg) \
30 " prfm pstl1strm, %2\n" \
33 "2: stlxr %w3, %w0, %2\n" \
37 " .pushsection .fixup,\"ax\"\n" \
42 _ASM_EXTABLE(1b, 4b) \
43 _ASM_EXTABLE(2b, 4b) \
44 : "=&r" (ret), "=&r" (oldval), "+Q" (*uaddr), "=&r" (tmp) \
45 : "r" (oparg), "Ir" (-EFAULT) \
51 futex_atomic_op_inuser(unsigned int encoded_op
, u32 __user
*uaddr
)
53 int op
= (encoded_op
>> 28) & 7;
54 int cmp
= (encoded_op
>> 24) & 15;
55 int oparg
= (int)(encoded_op
<< 8) >> 20;
56 int cmparg
= (int)(encoded_op
<< 20) >> 20;
57 int oldval
= 0, ret
, tmp
;
59 if (encoded_op
& (FUTEX_OP_OPARG_SHIFT
<< 28))
60 oparg
= 1U << (oparg
& 0x1f);
62 if (!access_ok(VERIFY_WRITE
, uaddr
, sizeof(u32
)))
69 __futex_atomic_op("mov %w0, %w4",
70 ret
, oldval
, uaddr
, tmp
, oparg
);
73 __futex_atomic_op("add %w0, %w1, %w4",
74 ret
, oldval
, uaddr
, tmp
, oparg
);
77 __futex_atomic_op("orr %w0, %w1, %w4",
78 ret
, oldval
, uaddr
, tmp
, oparg
);
81 __futex_atomic_op("and %w0, %w1, %w4",
82 ret
, oldval
, uaddr
, tmp
, ~oparg
);
85 __futex_atomic_op("eor %w0, %w1, %w4",
86 ret
, oldval
, uaddr
, tmp
, oparg
);
96 case FUTEX_OP_CMP_EQ
: ret
= (oldval
== cmparg
); break;
97 case FUTEX_OP_CMP_NE
: ret
= (oldval
!= cmparg
); break;
98 case FUTEX_OP_CMP_LT
: ret
= (oldval
< cmparg
); break;
99 case FUTEX_OP_CMP_GE
: ret
= (oldval
>= cmparg
); break;
100 case FUTEX_OP_CMP_LE
: ret
= (oldval
<= cmparg
); break;
101 case FUTEX_OP_CMP_GT
: ret
= (oldval
> cmparg
); break;
102 default: ret
= -ENOSYS
;
109 futex_atomic_cmpxchg_inatomic(u32
*uval
, u32 __user
*uaddr
,
110 u32 oldval
, u32 newval
)
115 if (!access_ok(VERIFY_WRITE
, uaddr
, sizeof(u32
)))
119 asm volatile("// futex_atomic_cmpxchg_inatomic\n"
120 " prfm pstl1strm, %2\n"
122 " sub %w3, %w1, %w4\n"
124 "2: stlxr %w3, %w5, %2\n"
128 " .pushsection .fixup,\"ax\"\n"
134 : "+r" (ret
), "=&r" (val
), "+Q" (*uaddr
), "=&r" (tmp
)
135 : "r" (oldval
), "r" (newval
), "Ir" (-EFAULT
)
143 #endif /* __KERNEL__ */
144 #endif /* __ASM_FUTEX_H */