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| /* SPDX-License-Identifier: GPL-2.0 */
| #ifndef _ASM_HEXAGON_FUTEX_H
| #define _ASM_HEXAGON_FUTEX_H
|
| #ifdef __KERNEL__
|
| #include <linux/futex.h>
| #include <linux/uaccess.h>
| #include <asm/errno.h>
|
| /* XXX TODO-- need to add sync barriers! */
|
| #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
| __asm__ __volatile( \
| "1: %0 = memw_locked(%3);\n" \
| /* For example: %1 = %4 */ \
| insn \
| "2: memw_locked(%3,p2) = %1;\n" \
| " if (!p2) jump 1b;\n" \
| " %1 = #0;\n" \
| "3:\n" \
| ".section .fixup,\"ax\"\n" \
| "4: %1 = #%5;\n" \
| " jump ##3b\n" \
| ".previous\n" \
| ".section __ex_table,\"a\"\n" \
| ".long 1b,4b,2b,4b\n" \
| ".previous\n" \
| : "=&r" (oldval), "=&r" (ret), "+m" (*uaddr) \
| : "r" (uaddr), "r" (oparg), "i" (-EFAULT) \
| : "p2", "memory")
|
|
| 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("%1 = %4\n", ret, oldval, uaddr, oparg);
| break;
| case FUTEX_OP_ADD:
| __futex_atomic_op("%1 = add(%0,%4)\n", ret, oldval, uaddr,
| oparg);
| break;
| case FUTEX_OP_OR:
| __futex_atomic_op("%1 = or(%0,%4)\n", ret, oldval, uaddr,
| oparg);
| break;
| case FUTEX_OP_ANDN:
| __futex_atomic_op("%1 = not(%4); %1 = and(%0,%1)\n", ret,
| oldval, uaddr, oparg);
| break;
| case FUTEX_OP_XOR:
| __futex_atomic_op("%1 = xor(%0,%4)\n", ret, oldval, uaddr,
| oparg);
| break;
| default:
| ret = -ENOSYS;
| }
|
| if (!ret)
| *oval = oldval;
|
| return ret;
| }
|
| static inline int
| futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval,
| u32 newval)
| {
| int prev;
| int ret;
|
| if (!access_ok(uaddr, sizeof(u32)))
| return -EFAULT;
|
| __asm__ __volatile__ (
| "1: %1 = memw_locked(%3)\n"
| " {\n"
| " p2 = cmp.eq(%1,%4)\n"
| " if (!p2.new) jump:NT 3f\n"
| " }\n"
| "2: memw_locked(%3,p2) = %5\n"
| " if (!p2) jump 1b\n"
| "3:\n"
| ".section .fixup,\"ax\"\n"
| "4: %0 = #%6\n"
| " jump ##3b\n"
| ".previous\n"
| ".section __ex_table,\"a\"\n"
| ".long 1b,4b,2b,4b\n"
| ".previous\n"
| : "+r" (ret), "=&r" (prev), "+m" (*uaddr)
| : "r" (uaddr), "r" (oldval), "r" (newval), "i"(-EFAULT)
| : "p2", "memory");
|
| *uval = prev;
| return ret;
| }
|
| #endif /* __KERNEL__ */
| #endif /* _ASM_HEXAGON_FUTEX_H */
|
|
