mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-06 02:50:43 +00:00
![David Gibson](/assets/img/avatar_default.png)
This patch consolidates macros used to generate assembly for compatibility across different CPUs or configs. A new header, asm-powerpc/asm-compat.h contains the main compatibility macros. It uses some preprocessor magic to make the macros suitable both for use in .S files, and in inline asm in .c files. Headers (bitops.h, uaccess.h, atomic.h, bug.h) which had their own such compatibility macros are changed to use asm-compat.h. ppc_asm.h is now for use in .S files *only*, and a #error enforces that. As such, we're a lot more careless about namespace pollution here than in asm-compat.h. While we're at it, this patch adds a call to the PPC405_ERR77 macro in futex.h which should have had it already, but didn't. Built and booted on pSeries, Maple and iSeries (ARCH=powerpc). Built for 32-bit powermac (ARCH=powerpc) and Walnut (ARCH=ppc). Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
85 lines
2.1 KiB
C
85 lines
2.1 KiB
C
#ifndef _ASM_POWERPC_FUTEX_H
|
|
#define _ASM_POWERPC_FUTEX_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/futex.h>
|
|
#include <asm/errno.h>
|
|
#include <asm/synch.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/asm-compat.h>
|
|
|
|
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
|
|
__asm__ __volatile ( \
|
|
SYNC_ON_SMP \
|
|
"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), "1" (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;
|
|
|
|
inc_preempt_count();
|
|
|
|
switch (op) {
|
|
case FUTEX_OP_SET:
|
|
__futex_atomic_op("", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ADD:
|
|
__futex_atomic_op("add %1,%0,%1\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_OR:
|
|
__futex_atomic_op("or %1,%0,%1\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_ANDN:
|
|
__futex_atomic_op("andc %1,%0,%1\n", ret, oldval, uaddr, oparg);
|
|
break;
|
|
case FUTEX_OP_XOR:
|
|
__futex_atomic_op("xor %1,%0,%1\n", ret, oldval, 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;
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _ASM_POWERPC_FUTEX_H */
|