#ifndef _ASM_FUTEX_H #define _ASM_FUTEX_H #ifdef __KERNEL__ #include #include #include #include #include #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \ __asm__ __volatile ( \ "1: " insn "\n" \ "2: .section .fixup,\"ax\"\n\ 3: mov %3, %1\n\ jmp 2b\n\ .previous\n\ .section __ex_table,\"a\"\n\ .align 8\n\ .long 1b,3b\n\ .previous" \ : "=r" (oldval), "=r" (ret), "=m" (*uaddr) \ : "i" (-EFAULT), "m" (*uaddr), "0" (oparg), "1" (0)) #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \ __asm__ __volatile ( \ "1: movl %2, %0\n\ movl %0, %3\n" \ insn "\n" \ "2: " LOCK_PREFIX "cmpxchgl %3, %2\n\ jnz 1b\n\ 3: .section .fixup,\"ax\"\n\ 4: mov %5, %1\n\ jmp 3b\n\ .previous\n\ .section __ex_table,\"a\"\n\ .align 8\n\ .long 1b,4b,2b,4b\n\ .previous" \ : "=&a" (oldval), "=&r" (ret), "=m" (*uaddr), \ "=&r" (tem) \ : "r" (oparg), "i" (-EFAULT), "m" (*uaddr), "1" (0)) 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, tem; if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) oparg = 1 << oparg; if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int))) return -EFAULT; inc_preempt_count(); if (op == FUTEX_OP_SET) __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg); else { #if !defined(CONFIG_X86_BSWAP) && !defined(CONFIG_UML) if (boot_cpu_data.x86 == 3) ret = -ENOSYS; else #endif switch (op) { case FUTEX_OP_ADD: __futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval, uaddr, oparg); break; case FUTEX_OP_OR: __futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg); break; case FUTEX_OP_ANDN: __futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg); break; case FUTEX_OP_XOR: __futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr, oparg); break; default: ret = -ENOSYS; } } dec_preempt_count(); 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; } #endif #endif