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| /* SPDX-License-Identifier: GPL-2.0 */
| #ifndef _ASM_X86_FUTEX_H
| #define _ASM_X86_FUTEX_H
|
| #ifdef __KERNEL__
|
| #include <linux/futex.h>
| #include <linux/uaccess.h>
|
| #include <asm/asm.h>
| #include <asm/errno.h>
| #include <asm/processor.h>
| #include <asm/smap.h>
|
| #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
| asm volatile("\t" ASM_STAC "\n" \
| "1:\t" insn "\n" \
| "2:\t" ASM_CLAC "\n" \
| "\t.section .fixup,\"ax\"\n" \
| "3:\tmov\t%3, %1\n" \
| "\tjmp\t2b\n" \
| "\t.previous\n" \
| _ASM_EXTABLE(1b, 3b) \
| : "=r" (oldval), "=r" (ret), "+m" (*uaddr) \
| : "i" (-EFAULT), "0" (oparg), "1" (0))
|
| #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
| asm volatile("\t" ASM_STAC "\n" \
| "1:\tmovl %2, %0\n" \
| "\tmovl\t%0, %3\n" \
| "\t" insn "\n" \
| "2:\t" LOCK_PREFIX "cmpxchgl %3, %2\n" \
| "\tjnz\t1b\n" \
| "3:\t" ASM_CLAC "\n" \
| "\t.section .fixup,\"ax\"\n" \
| "4:\tmov\t%5, %1\n" \
| "\tjmp\t3b\n" \
| "\t.previous\n" \
| _ASM_EXTABLE(1b, 4b) \
| _ASM_EXTABLE(2b, 4b) \
| : "=&a" (oldval), "=&r" (ret), \
| "+m" (*uaddr), "=&r" (tem) \
| : "r" (oparg), "i" (-EFAULT), "1" (0))
|
| static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
| u32 __user *uaddr)
| {
| int oldval = 0, ret, tem;
|
| pagefault_disable();
|
| switch (op) {
| case FUTEX_OP_SET:
| __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg);
| break;
| 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;
| }
|
| pagefault_enable();
|
| if (!ret)
| *oval = oldval;
|
| return ret;
| }
|
| static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
| u32 oldval, u32 newval)
| {
| return user_atomic_cmpxchg_inatomic(uval, uaddr, oldval, newval);
| }
|
| #endif
| #endif /* _ASM_X86_FUTEX_H */
|
|
