mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-18 17:54:13 +08:00
fc1d4c9c37
SH is able to support a complete futex implementation on UP by way of gUSA. However, IRQ toggling must be done for the old CPUs that don't have movli.l/movco.l (LL/SC) instructions. Provide a default implementation that does this, so it's possible to optimize for newer CPUs. Follows the same scheme as the current asm-sh/atomic-*.h headers. Signed-off-by: Kaz Kojima <kkojima@rr.iij4u.or.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
78 lines
1.8 KiB
C
78 lines
1.8 KiB
C
#ifndef __ASM_SH_FUTEX_H
|
|
#define __ASM_SH_FUTEX_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/futex.h>
|
|
#include <asm/errno.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
/* XXX: UP variants, fix for SH-4A and SMP.. */
|
|
#include <asm/futex-irq.h>
|
|
|
|
static inline int futex_atomic_op_inuser(int encoded_op, int __user *uaddr)
|
|
{
|
|
int op = (encoded_op >> 28) & 7;
|
|
int cmp = (encoded_op >> 24) & 15;
|
|
int oparg = (encoded_op << 8) >> 20;
|
|
int cmparg = (encoded_op << 20) >> 20;
|
|
int oldval = 0, ret;
|
|
|
|
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
|
|
oparg = 1 << oparg;
|
|
|
|
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
|
|
return -EFAULT;
|
|
|
|
pagefault_disable();
|
|
|
|
switch (op) {
|
|
case FUTEX_OP_SET:
|
|
ret = atomic_futex_op_xchg_set(oparg, uaddr, &oldval);
|
|
break;
|
|
case FUTEX_OP_ADD:
|
|
ret = atomic_futex_op_xchg_add(oparg, uaddr, &oldval);
|
|
break;
|
|
case FUTEX_OP_OR:
|
|
ret = atomic_futex_op_xchg_or(oparg, uaddr, &oldval);
|
|
break;
|
|
case FUTEX_OP_ANDN:
|
|
ret = atomic_futex_op_xchg_and(~oparg, uaddr, &oldval);
|
|
break;
|
|
case FUTEX_OP_XOR:
|
|
ret = atomic_futex_op_xchg_xor(oparg, uaddr, &oldval);
|
|
break;
|
|
default:
|
|
ret = -ENOSYS;
|
|
break;
|
|
}
|
|
|
|
pagefault_enable();
|
|
|
|
if (!ret) {
|
|
switch (cmp) {
|
|
case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
|
|
case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
|
|
case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
|
|
case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
|
|
case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
|
|
case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
|
|
default: ret = -ENOSYS;
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline int
|
|
futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
|
|
{
|
|
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
|
|
return -EFAULT;
|
|
|
|
return atomic_futex_op_cmpxchg_inatomic(uaddr, oldval, newval);
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* __ASM_SH_FUTEX_H */
|