mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-22 12:14:01 +08:00
3363fbdd6f
Add support for atomic futex operations. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
122 lines
3.1 KiB
C
122 lines
3.1 KiB
C
#ifndef _ASM_S390_FUTEX_H
|
|
#define _ASM_S390_FUTEX_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/futex.h>
|
|
#include <asm/errno.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#ifndef __s390x__
|
|
#define __futex_atomic_fixup \
|
|
".section __ex_table,\"a\"\n" \
|
|
" .align 4\n" \
|
|
" .long 0b,2b,1b,2b\n" \
|
|
".previous"
|
|
#else /* __s390x__ */
|
|
#define __futex_atomic_fixup \
|
|
".section __ex_table,\"a\"\n" \
|
|
" .align 8\n" \
|
|
" .quad 0b,2b,1b,2b\n" \
|
|
".previous"
|
|
#endif /* __s390x__ */
|
|
|
|
#define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \
|
|
asm volatile(" l %1,0(%6)\n" \
|
|
"0: " insn \
|
|
" cs %1,%2,0(%6)\n" \
|
|
"1: jl 0b\n" \
|
|
" lhi %0,0\n" \
|
|
"2:\n" \
|
|
__futex_atomic_fixup \
|
|
: "=d" (ret), "=&d" (oldval), "=&d" (newval), \
|
|
"=m" (*uaddr) \
|
|
: "0" (-EFAULT), "d" (oparg), "a" (uaddr), \
|
|
"m" (*uaddr) : "cc" );
|
|
|
|
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, newval, ret;
|
|
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
|
|
oparg = 1 << oparg;
|
|
|
|
if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
|
|
return -EFAULT;
|
|
|
|
inc_preempt_count();
|
|
|
|
switch (op) {
|
|
case FUTEX_OP_SET:
|
|
__futex_atomic_op("lr %2,%5\n",
|
|
ret, oldval, newval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ADD:
|
|
__futex_atomic_op("lr %2,%1\nar %2,%5\n",
|
|
ret, oldval, newval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_OR:
|
|
__futex_atomic_op("lr %2,%1\nor %2,%5\n",
|
|
ret, oldval, newval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ANDN:
|
|
__futex_atomic_op("lr %2,%1\nnr %2,%5\n",
|
|
ret, oldval, newval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_XOR:
|
|
__futex_atomic_op("lr %2,%1\nxr %2,%5\n",
|
|
ret, oldval, newval, uaddr, oparg);
|
|
break;
|
|
default:
|
|
ret = -ENOSYS;
|
|
}
|
|
|
|
dec_preempt_count();
|
|
|
|
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 ret;
|
|
|
|
if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
|
|
return -EFAULT;
|
|
asm volatile(" cs %1,%4,0(%5)\n"
|
|
"0: lr %0,%1\n"
|
|
"1:\n"
|
|
#ifndef __s390x__
|
|
".section __ex_table,\"a\"\n"
|
|
" .align 4\n"
|
|
" .long 0b,1b\n"
|
|
".previous"
|
|
#else /* __s390x__ */
|
|
".section __ex_table,\"a\"\n"
|
|
" .align 8\n"
|
|
" .quad 0b,1b\n"
|
|
".previous"
|
|
#endif /* __s390x__ */
|
|
: "=d" (ret), "+d" (oldval), "=m" (*uaddr)
|
|
: "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr)
|
|
: "cc", "memory" );
|
|
return oldval;
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _ASM_S390_FUTEX_H */
|