diff options
Diffstat (limited to 'arch/alpha/include/asm')
| -rw-r--r-- | arch/alpha/include/asm/barrier.h | 2 | ||||
| -rw-r--r-- | arch/alpha/include/asm/futex.h | 118 |
2 files changed, 116 insertions, 4 deletions
diff --git a/arch/alpha/include/asm/barrier.h b/arch/alpha/include/asm/barrier.h index ac78eba909b..ce8860a0b32 100644 --- a/arch/alpha/include/asm/barrier.h +++ b/arch/alpha/include/asm/barrier.h @@ -16,11 +16,13 @@ __asm__ __volatile__("wmb": : :"memory") __asm__ __volatile__("mb": : :"memory") #ifdef CONFIG_SMP +#define __ASM_SMP_MB "\tmb\n" #define smp_mb() mb() #define smp_rmb() rmb() #define smp_wmb() wmb() #define smp_read_barrier_depends() read_barrier_depends() #else +#define __ASM_SMP_MB #define smp_mb() barrier() #define smp_rmb() barrier() #define smp_wmb() barrier() diff --git a/arch/alpha/include/asm/futex.h b/arch/alpha/include/asm/futex.h index 6a332a9f099..945de222ab9 100644 --- a/arch/alpha/include/asm/futex.h +++ b/arch/alpha/include/asm/futex.h @@ -1,6 +1,116 @@ -#ifndef _ASM_FUTEX_H -#define _ASM_FUTEX_H +#ifndef _ASM_ALPHA_FUTEX_H +#define _ASM_ALPHA_FUTEX_H -#include <asm-generic/futex.h> +#ifdef __KERNEL__ -#endif +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <asm/errno.h> +#include <asm/barrier.h> + +#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ + __asm__ __volatile__( \ + __ASM_SMP_MB \ + "1: ldl_l %0,0(%2)\n" \ + insn \ + "2: stl_c %1,0(%2)\n" \ + " beq %1,4f\n" \ + " mov $31,%1\n" \ + "3: .subsection 2\n" \ + "4: br 1b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .long 1b-.\n" \ + " lda $31,3b-1b(%1)\n" \ + " .long 2b-.\n" \ + " lda $31,3b-2b(%1)\n" \ + " .previous\n" \ + : "=&r" (oldval), "=&r"(ret) \ + : "r" (uaddr), "r"(oparg) \ + : "memory") + +static inline int futex_atomic_op_inuser (int encoded_op, int __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(int))) + return -EFAULT; + + pagefault_disable(); + + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op("mov %3,%1\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op("addl %0,%3,%1\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op("or %0,%3,%1\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op("andnot %0,%3,%1\n", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op("xor %0,%3,%1\n", ret, oldval, uaddr, oparg); + break; + 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(int __user *uaddr, int oldval, int newval) +{ + int prev, cmp; + + if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int))) + return -EFAULT; + + __asm__ __volatile__ ( + __ASM_SMP_MB + "1: ldl_l %0,0(%2)\n" + " cmpeq %0,%3,%1\n" + " beq %1,3f\n" + " mov %4,%1\n" + "2: stl_c %1,0(%2)\n" + " beq %1,4f\n" + "3: .subsection 2\n" + "4: br 1b\n" + " .previous\n" + " .section __ex_table,\"a\"\n" + " .long 1b-.\n" + " lda $31,3b-1b(%0)\n" + " .long 2b-.\n" + " lda $31,3b-2b(%0)\n" + " .previous\n" + : "=&r"(prev), "=&r"(cmp) + : "r"(uaddr), "r"((long)oldval), "r"(newval) + : "memory"); + + return prev; +} + +#endif /* __KERNEL__ */ +#endif /* _ASM_ALPHA_FUTEX_H */ |