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 (2017B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef _ASM_ALPHA_FUTEX_H
      3#define _ASM_ALPHA_FUTEX_H
      4
      5#ifdef __KERNEL__
      6
      7#include <linux/futex.h>
      8#include <linux/uaccess.h>
      9#include <asm/errno.h>
     10#include <asm/barrier.h>
     11
     12#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg)	\
     13	__asm__ __volatile__(					\
     14		__ASM_SMP_MB					\
     15	"1:	ldl_l	%0,0(%2)\n"				\
     16		insn						\
     17	"2:	stl_c	%1,0(%2)\n"				\
     18	"	beq	%1,4f\n"				\
     19	"	mov	$31,%1\n"				\
     20	"3:	.subsection 2\n"				\
     21	"4:	br	1b\n"					\
     22	"	.previous\n"					\
     23	EXC(1b,3b,$31,%1)					\
     24	EXC(2b,3b,$31,%1)					\
     25	:	"=&r" (oldval), "=&r"(ret)			\
     26	:	"r" (uaddr), "r"(oparg)				\
     27	:	"memory")
     28
     29static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
     30		u32 __user *uaddr)
     31{
     32	int oldval = 0, ret;
     33
     34	if (!access_ok(uaddr, sizeof(u32)))
     35		return -EFAULT;
     36
     37	switch (op) {
     38	case FUTEX_OP_SET:
     39		__futex_atomic_op("mov %3,%1\n", ret, oldval, uaddr, oparg);
     40		break;
     41	case FUTEX_OP_ADD:
     42		__futex_atomic_op("addl %0,%3,%1\n", ret, oldval, uaddr, oparg);
     43		break;
     44	case FUTEX_OP_OR:
     45		__futex_atomic_op("or %0,%3,%1\n", ret, oldval, uaddr, oparg);
     46		break;
     47	case FUTEX_OP_ANDN:
     48		__futex_atomic_op("andnot %0,%3,%1\n", ret, oldval, uaddr, oparg);
     49		break;
     50	case FUTEX_OP_XOR:
     51		__futex_atomic_op("xor %0,%3,%1\n", ret, oldval, uaddr, oparg);
     52		break;
     53	default:
     54		ret = -ENOSYS;
     55	}
     56
     57	if (!ret)
     58		*oval = oldval;
     59
     60	return ret;
     61}
     62
     63static inline int
     64futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
     65			      u32 oldval, u32 newval)
     66{
     67	int ret = 0, cmp;
     68	u32 prev;
     69
     70	if (!access_ok(uaddr, sizeof(u32)))
     71		return -EFAULT;
     72
     73	__asm__ __volatile__ (
     74		__ASM_SMP_MB
     75	"1:	ldl_l	%1,0(%3)\n"
     76	"	cmpeq	%1,%4,%2\n"
     77	"	beq	%2,3f\n"
     78	"	mov	%5,%2\n"
     79	"2:	stl_c	%2,0(%3)\n"
     80	"	beq	%2,4f\n"
     81	"3:	.subsection 2\n"
     82	"4:	br	1b\n"
     83	"	.previous\n"
     84	EXC(1b,3b,$31,%0)
     85	EXC(2b,3b,$31,%0)
     86	:	"+r"(ret), "=&r"(prev), "=&r"(cmp)
     87	:	"r"(uaddr), "r"((long)(int)oldval), "r"(newval)
     88	:	"memory");
     89
     90	*uval = prev;
     91	return ret;
     92}
     93
     94#endif /* __KERNEL__ */
     95#endif /* _ASM_ALPHA_FUTEX_H */