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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/xtensa/include/asm/futex.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/xtensa/include/asm/futex.h')
-rw-r--r-- | kernel/arch/xtensa/include/asm/futex.h | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/kernel/arch/xtensa/include/asm/futex.h b/kernel/arch/xtensa/include/asm/futex.h new file mode 100644 index 000000000..b39531bab --- /dev/null +++ b/kernel/arch/xtensa/include/asm/futex.h @@ -0,0 +1,147 @@ +/* + * Atomic futex routines + * + * Based on the PowerPC implementataion + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Copyright (C) 2013 TangoTec Ltd. + * + * Baruch Siach <baruch@tkos.co.il> + */ + +#ifndef _ASM_XTENSA_FUTEX_H +#define _ASM_XTENSA_FUTEX_H + +#ifdef __KERNEL__ + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <linux/errno.h> + +#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ + __asm__ __volatile( \ + "1: l32i %0, %2, 0\n" \ + insn "\n" \ + " wsr %0, scompare1\n" \ + "2: s32c1i %1, %2, 0\n" \ + " bne %1, %0, 1b\n" \ + " movi %1, 0\n" \ + "3:\n" \ + " .section .fixup,\"ax\"\n" \ + " .align 4\n" \ + "4: .long 3b\n" \ + "5: l32r %0, 4b\n" \ + " movi %1, %3\n" \ + " jx %0\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .long 1b,5b,2b,5b\n" \ + " .previous\n" \ + : "=&r" (oldval), "=&r" (ret) \ + : "r" (uaddr), "I" (-EFAULT), "r" (oparg) \ + : "memory") + +static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr) +{ + int op = (encoded_op >> 28) & 7; + int cmp = (encoded_op >> 24) & 15; + int oparg = (encoded_op << 8) >> 20; + int cmparg = (encoded_op << 20) >> 20; + int oldval = 0, ret; + if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) + oparg = 1 << oparg; + + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + +#if !XCHAL_HAVE_S32C1I + return -ENOSYS; +#endif + + pagefault_disable(); + + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op("mov %1, %4", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op("add %1, %0, %4", ret, oldval, uaddr, + oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op("or %1, %0, %4", ret, oldval, uaddr, + oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op("and %1, %0, %4", ret, oldval, uaddr, + ~oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op("xor %1, %0, %4", ret, oldval, uaddr, + oparg); + break; + default: + ret = -ENOSYS; + } + + pagefault_enable(); + + if (ret) + return ret; + + switch (cmp) { + case FUTEX_OP_CMP_EQ: return (oldval == cmparg); + case FUTEX_OP_CMP_NE: return (oldval != cmparg); + case FUTEX_OP_CMP_LT: return (oldval < cmparg); + case FUTEX_OP_CMP_GE: return (oldval >= cmparg); + case FUTEX_OP_CMP_LE: return (oldval <= cmparg); + case FUTEX_OP_CMP_GT: return (oldval > cmparg); + } + + return -ENOSYS; +} + +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + int ret = 0; + u32 prev; + + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) + return -EFAULT; + +#if !XCHAL_HAVE_S32C1I + return -ENOSYS; +#endif + + __asm__ __volatile__ ( + " # futex_atomic_cmpxchg_inatomic\n" + "1: l32i %1, %3, 0\n" + " mov %0, %5\n" + " wsr %1, scompare1\n" + "2: s32c1i %0, %3, 0\n" + "3:\n" + " .section .fixup,\"ax\"\n" + " .align 4\n" + "4: .long 3b\n" + "5: l32r %1, 4b\n" + " movi %0, %6\n" + " jx %1\n" + " .previous\n" + " .section __ex_table,\"a\"\n" + " .long 1b,5b,2b,5b\n" + " .previous\n" + : "+r" (ret), "=&r" (prev), "+m" (*uaddr) + : "r" (uaddr), "r" (oldval), "r" (newval), "I" (-EFAULT) + : "memory"); + + *uval = prev; + return ret; +} + +#endif /* __KERNEL__ */ +#endif /* _ASM_XTENSA_FUTEX_H */ |