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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright IBM Corp. 1999, 2011
*
* Author(s): Martin Schwidefsky <[email protected]>,
*/
#ifndef __ASM_CMPXCHG_H
#define __ASM_CMPXCHG_H
#include <linux/mmdebug.h>
#include <linux/types.h>
#include <linux/bug.h>
void __xchg_called_with_bad_pointer(void);
static __always_inline unsigned long __xchg(unsigned long x,
unsigned long address, int size)
{
unsigned long old;
int shift;
switch (size) {
case 1:
shift = (3 ^ (address & 3)) << 3;
address ^= address & 3;
asm volatile(
" l %0,%1\n"
"0: lr 0,%0\n"
" nr 0,%3\n"
" or 0,%2\n"
" cs %0,0,%1\n"
" jl 0b\n"
: "=&d" (old), "+Q" (*(int *) address)
: "d" ((x & 0xff) << shift), "d" (~(0xff << shift))
: "memory", "cc", "0");
return old >> shift;
case 2:
shift = (2 ^ (address & 2)) << 3;
address ^= address & 2;
asm volatile(
" l %0,%1\n"
"0: lr 0,%0\n"
" nr 0,%3\n"
" or 0,%2\n"
" cs %0,0,%1\n"
" jl 0b\n"
: "=&d" (old), "+Q" (*(int *) address)
: "d" ((x & 0xffff) << shift), "d" (~(0xffff << shift))
: "memory", "cc", "0");
return old >> shift;
case 4:
asm volatile(
" l %0,%1\n"
"0: cs %0,%2,%1\n"
" jl 0b\n"
: "=&d" (old), "+Q" (*(int *) address)
: "d" (x)
: "memory", "cc");
return old;
case 8:
asm volatile(
" lg %0,%1\n"
"0: csg %0,%2,%1\n"
" jl 0b\n"
: "=&d" (old), "+QS" (*(long *) address)
: "d" (x)
: "memory", "cc");
return old;
}
__xchg_called_with_bad_pointer();
return x;
}
#define arch_xchg(ptr, x) \
({ \
__typeof__(*(ptr)) __ret; \
\
__ret = (__typeof__(*(ptr))) \
__xchg((unsigned long)(x), (unsigned long)(ptr), \
sizeof(*(ptr))); \
__ret; \
})
void __cmpxchg_called_with_bad_pointer(void);
static __always_inline unsigned long __cmpxchg(unsigned long address,
unsigned long old,
unsigned long new, int size)
{
unsigned long prev, tmp;
int shift;
switch (size) {
case 1:
shift = (3 ^ (address & 3)) << 3;
address ^= address & 3;
asm volatile(
" l %0,%2\n"
"0: nr %0,%5\n"
" lr %1,%0\n"
" or %0,%3\n"
" or %1,%4\n"
" cs %0,%1,%2\n"
" jnl 1f\n"
" xr %1,%0\n"
" nr %1,%5\n"
" jnz 0b\n"
"1:"
: "=&d" (prev), "=&d" (tmp), "+Q" (*(int *) address)
: "d" ((old & 0xff) << shift),
"d" ((new & 0xff) << shift),
"d" (~(0xff << shift))
: "memory", "cc");
return prev >> shift;
case 2:
shift = (2 ^ (address & 2)) << 3;
address ^= address & 2;
asm volatile(
" l %0,%2\n"
"0: nr %0,%5\n"
" lr %1,%0\n"
" or %0,%3\n"
" or %1,%4\n"
" cs %0,%1,%2\n"
" jnl 1f\n"
" xr %1,%0\n"
" nr %1,%5\n"
" jnz 0b\n"
"1:"
: "=&d" (prev), "=&d" (tmp), "+Q" (*(int *) address)
: "d" ((old & 0xffff) << shift),
"d" ((new & 0xffff) << shift),
"d" (~(0xffff << shift))
: "memory", "cc");
return prev >> shift;
case 4:
asm volatile(
" cs %0,%3,%1\n"
: "=&d" (prev), "+Q" (*(int *) address)
: "0" (old), "d" (new)
: "memory", "cc");
return prev;
case 8:
asm volatile(
" csg %0,%3,%1\n"
: "=&d" (prev), "+QS" (*(long *) address)
: "0" (old), "d" (new)
: "memory", "cc");
return prev;
}
__cmpxchg_called_with_bad_pointer();
return old;
}
#define arch_cmpxchg(ptr, o, n) \
({ \
__typeof__(*(ptr)) __ret; \
\
__ret = (__typeof__(*(ptr))) \
__cmpxchg((unsigned long)(ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))); \
__ret; \
})
#define arch_cmpxchg64 arch_cmpxchg
#define arch_cmpxchg_local arch_cmpxchg
#define arch_cmpxchg64_local arch_cmpxchg
#define system_has_cmpxchg_double() 1
static __always_inline int __cmpxchg_double(unsigned long p1, unsigned long p2,
unsigned long o1, unsigned long o2,
unsigned long n1, unsigned long n2)
{
union register_pair old = { .even = o1, .odd = o2, };
union register_pair new = { .even = n1, .odd = n2, };
int cc;
asm volatile(
" cdsg %[old],%[new],%[ptr]\n"
" ipm %[cc]\n"
" srl %[cc],28\n"
: [cc] "=&d" (cc), [old] "+&d" (old.pair)
: [new] "d" (new.pair),
[ptr] "QS" (*(unsigned long *)p1), "Q" (*(unsigned long *)p2)
: "memory", "cc");
return !cc;
}
#define arch_cmpxchg_double(p1, p2, o1, o2, n1, n2) \
({ \
typeof(p1) __p1 = (p1); \
typeof(p2) __p2 = (p2); \
\
BUILD_BUG_ON(sizeof(*(p1)) != sizeof(long)); \
BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long)); \
VM_BUG_ON((unsigned long)((__p1) + 1) != (unsigned long)(__p2));\
__cmpxchg_double((unsigned long)__p1, (unsigned long)__p2, \
(unsigned long)(o1), (unsigned long)(o2), \
(unsigned long)(n1), (unsigned long)(n2)); \
})
#endif /* __ASM_CMPXCHG_H */
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