/* SPDX-License-Identifier: GPL-2.0 */ // Copyright (C) 2005-2017 Andes Technology Corporation #ifndef __NDS32_FUTEX_H__ #define __NDS32_FUTEX_H__ #include <linux/futex.h> #include <linux/uaccess.h> #include <asm/errno.h> #define __futex_atomic_ex_table(err_reg) \ " .pushsection __ex_table,\"a\"\n" \ " .align 3\n" \ " .long 1b, 4f\n" \ " .long 2b, 4f\n" \ " .popsection\n" \ " .pushsection .fixup,\"ax\"\n" \ "4: move %0, " err_reg "\n" \ " b 3b\n" \ " .popsection" #define __futex_atomic_op(insn, ret, oldval, tmp, uaddr, oparg) \ smp_mb(); \ asm volatile( \ " movi $ta, #0\n" \ "1: llw %1, [%2+$ta]\n" \ " " insn "\n" \ "2: scw %0, [%2+$ta]\n" \ " beqz %0, 1b\n" \ " movi %0, #0\n" \ "3:\n" \ __futex_atomic_ex_table("%4") \ : "=&r" (ret), "=&r" (oldval) \ : "r" (uaddr), "r" (oparg), "i" (-EFAULT) \ : "cc", "memory") static inline int futex_atomic_cmpxchg_inatomic(u32 * uval, u32 __user * uaddr, u32 oldval, u32 newval) { int ret = 0; u32 val, tmp, flags; if (!access_ok(uaddr, sizeof(u32))) return -EFAULT; smp_mb(); asm volatile (" movi $ta, #0\n" "1: llw %1, [%6 + $ta]\n" " sub %3, %1, %4\n" " cmovz %2, %5, %3\n" " cmovn %2, %1, %3\n" "2: scw %2, [%6 + $ta]\n" " beqz %2, 1b\n" "3:\n " __futex_atomic_ex_table("%7") :"+&r"(ret), "=&r"(val), "=&r"(tmp), "=&r"(flags) :"r"(oldval), "r"(newval), "r"(uaddr), "i"(-EFAULT) :"$ta", "memory"); smp_mb(); *uval = val; return ret; } static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) { int oldval = 0, ret; if (!access_ok(uaddr, sizeof(u32))) return -EFAULT; switch (op) { case FUTEX_OP_SET: __futex_atomic_op("move %0, %3", ret, oldval, tmp, uaddr, oparg); break; case FUTEX_OP_ADD: __futex_atomic_op("add %0, %1, %3", ret, oldval, tmp, uaddr, oparg); break; case FUTEX_OP_OR: __futex_atomic_op("or %0, %1, %3", ret, oldval, tmp, uaddr, oparg); break; case FUTEX_OP_ANDN: __futex_atomic_op("and %0, %1, %3", ret, oldval, tmp, uaddr, ~oparg); break; case FUTEX_OP_XOR: __futex_atomic_op("xor %0, %1, %3", ret, oldval, tmp, uaddr, oparg); break; default: ret = -ENOSYS; } if (!ret) *oval = oldval; return ret; } #endif /* __NDS32_FUTEX_H__ */