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#ifndef _ASM_POWERPC_FUTEX_H
#define _ASM_POWERPC_FUTEX_H
#ifdef __KERNEL__
#include <linux/futex.h>
#include <linux/uaccess.h>
#include <asm/errno.h>
#include <asm/synch.h>
#include <asm/asm-compat.h>
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
__asm__ __volatile ( \
PPC_RELEASE_BARRIER \
"1: lwarx %0,0,%2\n" \
insn \
PPC405_ERR77(0, %2) \
"2: stwcx. %1,0,%2\n" \
"bne- 1b\n" \
"li %1,0\n" \
"3: .section .fixup,\"ax\"\n" \
"4: li %1,%3\n" \
"b 3b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
".align 3\n" \
PPC_LONG "1b,4b,2b,4b\n" \
".previous" \
: "=&r" (oldval), "=&r" (ret) \
: "b" (uaddr), "i" (-EFAULT), "r" (oparg) \
: "cr0", "memory")
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:
__futex_atomic_op("mr %1,%4\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("add %1,%0,%4\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("or %1,%0,%4\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("andc %1,%0,%4\n", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("xor %1,%0,%4\n", ret, oldval, uaddr, oparg);
break;
default:
ret = -ENOSYS;
}
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)
{
int prev;
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
return -EFAULT;
__asm__ __volatile__ (
PPC_RELEASE_BARRIER
"1: lwarx %0,0,%2 # futex_atomic_cmpxchg_inatomic\n\
cmpw 0,%0,%3\n\
bne- 3f\n"
PPC405_ERR77(0,%2)
"2: stwcx. %4,0,%2\n\
bne- 1b\n"
PPC_ACQUIRE_BARRIER
"3: .section .fixup,\"ax\"\n\
4: li %0,%5\n\
b 3b\n\
.previous\n\
.section __ex_table,\"a\"\n\
.align 3\n\
" PPC_LONG "1b,4b,2b,4b\n\
.previous" \
: "=&r" (prev), "+m" (*uaddr)
: "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT)
: "cc", "memory");
return prev;
}
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_FUTEX_H */
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