From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: 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 Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior 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 --- kernel/include/asm-generic/futex.h | 174 +++++++++++++++++++++++++++++++++++++ 1 file changed, 174 insertions(+) create mode 100644 kernel/include/asm-generic/futex.h (limited to 'kernel/include/asm-generic/futex.h') diff --git a/kernel/include/asm-generic/futex.h b/kernel/include/asm-generic/futex.h new file mode 100644 index 000000000..e56272c91 --- /dev/null +++ b/kernel/include/asm-generic/futex.h @@ -0,0 +1,174 @@ +#ifndef _ASM_GENERIC_FUTEX_H +#define _ASM_GENERIC_FUTEX_H + +#include +#include +#include + +#ifndef CONFIG_SMP +/* + * The following implementation only for uniprocessor machines. + * It relies on preempt_disable() ensuring mutual exclusion. + * + */ + +/** + * futex_atomic_op_inuser() - Atomic arithmetic operation with constant + * argument and comparison of the previous + * futex value with another constant. + * + * @encoded_op: encoded operation to execute + * @uaddr: pointer to user space address + * + * Return: + * 0 - On success + * <0 - On error + */ +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, ret; + u32 tmp; + + if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) + oparg = 1 << oparg; + + preempt_disable(); + pagefault_disable(); + + ret = -EFAULT; + if (unlikely(get_user(oldval, uaddr) != 0)) + goto out_pagefault_enable; + + ret = 0; + tmp = oldval; + + switch (op) { + case FUTEX_OP_SET: + tmp = oparg; + break; + case FUTEX_OP_ADD: + tmp += oparg; + break; + case FUTEX_OP_OR: + tmp |= oparg; + break; + case FUTEX_OP_ANDN: + tmp &= ~oparg; + break; + case FUTEX_OP_XOR: + tmp ^= oparg; + break; + default: + ret = -ENOSYS; + } + + if (ret == 0 && unlikely(put_user(tmp, uaddr) != 0)) + ret = -EFAULT; + +out_pagefault_enable: + pagefault_enable(); + preempt_enable(); + + if (ret == 0) { + switch (cmp) { + case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break; + case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break; + case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break; + case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break; + case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break; + case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break; + default: ret = -ENOSYS; + } + } + return ret; +} + +/** + * futex_atomic_cmpxchg_inatomic() - Compare and exchange the content of the + * uaddr with newval if the current value is + * oldval. + * @uval: pointer to store content of @uaddr + * @uaddr: pointer to user space address + * @oldval: old value + * @newval: new value to store to @uaddr + * + * Return: + * 0 - On success + * <0 - On error + */ +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + u32 val; + + preempt_disable(); + if (unlikely(get_user(val, uaddr) != 0)) + return -EFAULT; + + if (val == oldval && unlikely(put_user(newval, uaddr) != 0)) + return -EFAULT; + + *uval = val; + preempt_enable(); + + return 0; +} + +#else +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; + + pagefault_disable(); + + switch (op) { + case FUTEX_OP_SET: + case FUTEX_OP_ADD: + case FUTEX_OP_OR: + case FUTEX_OP_ANDN: + case FUTEX_OP_XOR: + default: + ret = -ENOSYS; + } + + pagefault_enable(); + + if (!ret) { + switch (cmp) { + case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break; + case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break; + case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break; + case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break; + case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break; + case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break; + default: ret = -ENOSYS; + } + } + return ret; +} + +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + return -ENOSYS; +} + +#endif /* CONFIG_SMP */ +#endif -- cgit 1.2.3-korg