cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

futex.h (2293B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef __ASM_OPENRISC_FUTEX_H
      3#define __ASM_OPENRISC_FUTEX_H
      4
      5#ifdef __KERNEL__
      6
      7#include <linux/futex.h>
      8#include <linux/uaccess.h>
      9#include <asm/errno.h>
     10
     11#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
     12({								\
     13	__asm__ __volatile__ (					\
     14		"1:	l.lwa	%0, %2			\n"	\
     15			insn				"\n"	\
     16		"2:	l.swa	%2, %1			\n"	\
     17		"	l.bnf	1b			\n"	\
     18		"	 l.ori	%1, r0, 0		\n"	\
     19		"3:					\n"	\
     20		".section .fixup,\"ax\"			\n"	\
     21		"4:	l.j	3b			\n"	\
     22		"	 l.addi	%1, r0, %3		\n"	\
     23		".previous				\n"	\
     24		".section __ex_table,\"a\"		\n"	\
     25		".word	1b,4b,2b,4b			\n"	\
     26		".previous				\n"	\
     27		: "=&r" (oldval), "=&r" (ret), "+m" (*uaddr)	\
     28		: "i" (-EFAULT), "r" (oparg)			\
     29		: "cc", "memory"				\
     30		);						\
     31})
     32
     33static inline int
     34arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
     35{
     36	int oldval = 0, ret;
     37
     38	if (!access_ok(uaddr, sizeof(u32)))
     39		return -EFAULT;
     40
     41	switch (op) {
     42	case FUTEX_OP_SET:
     43		__futex_atomic_op("l.or %1,%4,%4", ret, oldval, uaddr, oparg);
     44		break;
     45	case FUTEX_OP_ADD:
     46		__futex_atomic_op("l.add %1,%0,%4", ret, oldval, uaddr, oparg);
     47		break;
     48	case FUTEX_OP_OR:
     49		__futex_atomic_op("l.or %1,%0,%4", ret, oldval, uaddr, oparg);
     50		break;
     51	case FUTEX_OP_ANDN:
     52		__futex_atomic_op("l.and %1,%0,%4", ret, oldval, uaddr, ~oparg);
     53		break;
     54	case FUTEX_OP_XOR:
     55		__futex_atomic_op("l.xor %1,%0,%4", ret, oldval, uaddr, oparg);
     56		break;
     57	default:
     58		ret = -ENOSYS;
     59	}
     60
     61	if (!ret)
     62		*oval = oldval;
     63
     64	return ret;
     65}
     66
     67static inline int
     68futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
     69			      u32 oldval, u32 newval)
     70{
     71	int ret = 0;
     72	u32 prev;
     73
     74	if (!access_ok(uaddr, sizeof(u32)))
     75		return -EFAULT;
     76
     77	__asm__ __volatile__ (				\
     78		"1:	l.lwa	%1, %2		\n"	\
     79		"	l.sfeq	%1, %3		\n"	\
     80		"	l.bnf	3f		\n"	\
     81		"	 l.nop			\n"	\
     82		"2:	l.swa	%2, %4		\n"	\
     83		"	l.bnf	1b		\n"	\
     84		"	 l.nop			\n"	\
     85		"3:				\n"	\
     86		".section .fixup,\"ax\"		\n"	\
     87		"4:	l.j	3b		\n"	\
     88		"	 l.addi	%0, r0, %5	\n"	\
     89		".previous			\n"	\
     90		".section __ex_table,\"a\"	\n"	\
     91		".word	1b,4b,2b,4b		\n"	\
     92		".previous			\n"	\
     93		: "+r" (ret), "=&r" (prev), "+m" (*uaddr) \
     94		: "r" (oldval), "r" (newval), "i" (-EFAULT) \
     95		: "cc",	"memory"			\
     96		);
     97
     98	*uval = prev;
     99	return ret;
    100}
    101
    102#endif /* __KERNEL__ */
    103
    104#endif /* __ASM_OPENRISC_FUTEX_H */