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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_CSKY_FUTEX_H
#define __ASM_CSKY_FUTEX_H
#ifndef CONFIG_SMP
#include <asm-generic/futex.h>
#else
#include <linux/atomic.h>
#include <linux/futex.h>
#include <linux/uaccess.h>
#include <linux/errno.h>
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
{ \
u32 tmp; \
\
__atomic_pre_full_fence(); \
\
__asm__ __volatile__ ( \
"1: ldex.w %[ov], %[u] \n" \
" "insn" \n" \
"2: stex.w %[t], %[u] \n" \
" bez %[t], 1b \n" \
" br 4f \n" \
"3: mov %[r], %[e] \n" \
"4: \n" \
" .section __ex_table,\"a\" \n" \
" .balign 4 \n" \
" .long 1b, 3b \n" \
" .long 2b, 3b \n" \
" .previous \n" \
: [r] "+r" (ret), [ov] "=&r" (oldval), \
[u] "+m" (*uaddr), [t] "=&r" (tmp) \
: [op] "Jr" (oparg), [e] "jr" (-EFAULT) \
: "memory"); \
\
__atomic_post_full_fence(); \
}
static inline int
arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
{
int oldval = 0, ret = 0;
if (!access_ok(uaddr, sizeof(u32)))
return -EFAULT;
switch (op) {
case FUTEX_OP_SET:
__futex_atomic_op("mov %[t], %[ov]",
ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("add %[t], %[ov], %[op]",
ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("or %[t], %[ov], %[op]",
ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("and %[t], %[ov], %[op]",
ret, oldval, uaddr, ~oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("xor %[t], %[ov], %[op]",
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 ret = 0;
u32 val, tmp;
if (!access_ok(uaddr, sizeof(u32)))
return -EFAULT;
__atomic_pre_full_fence();
__asm__ __volatile__ (
"1: ldex.w %[v], %[u] \n"
" cmpne %[v], %[ov] \n"
" bt 4f \n"
" mov %[t], %[nv] \n"
"2: stex.w %[t], %[u] \n"
" bez %[t], 1b \n"
" br 4f \n"
"3: mov %[r], %[e] \n"
"4: \n"
" .section __ex_table,\"a\" \n"
" .balign 4 \n"
" .long 1b, 3b \n"
" .long 2b, 3b \n"
" .previous \n"
: [r] "+r" (ret), [v] "=&r" (val), [u] "+m" (*uaddr),
[t] "=&r" (tmp)
: [ov] "Jr" (oldval), [nv] "Jr" (newval), [e] "Jr" (-EFAULT)
: "memory");
__atomic_post_full_fence();
*uval = val;
return ret;
}
#endif /* CONFIG_SMP */
#endif /* __ASM_CSKY_FUTEX_H */
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