diff options
Diffstat (limited to 'arch/m68k/include/asm/futex.h')
-rw-r--r-- | arch/m68k/include/asm/futex.h | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/m68k/include/asm/futex.h b/arch/m68k/include/asm/futex.h new file mode 100644 index 00000000000..bc868af10c9 --- /dev/null +++ b/arch/m68k/include/asm/futex.h @@ -0,0 +1,94 @@ +#ifndef _ASM_M68K_FUTEX_H +#define _ASM_M68K_FUTEX_H + +#ifdef __KERNEL__ +#if !defined(CONFIG_MMU) +#include <asm-generic/futex.h> +#else /* CONFIG_MMU */ + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <asm/errno.h> + +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, + u32 oldval, u32 newval) +{ + u32 val; + + if (unlikely(get_user(val, uaddr) != 0)) + return -EFAULT; + + if (val == oldval && unlikely(put_user(newval, uaddr) != 0)) + return -EFAULT; + + *uval = val; + + return 0; +} + +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; + + pagefault_disable(); /* implies preempt_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(); /* subsumes 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; +} + +#endif /* CONFIG_MMU */ +#endif /* __KERNEL__ */ +#endif /* _ASM_M68K_FUTEX_H */ |