linux-hardened/arch/s390/lib/uaccess_mvcos.c
Heiko Carstens a53c8fab3f s390/comments: unify copyright messages and remove file names
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 11:15:04 +02:00

225 lines
5.9 KiB
C

/*
* Optimized user space space access functions based on mvcos.
*
* Copyright IBM Corp. 2006
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
* Gerald Schaefer (gerald.schaefer@de.ibm.com)
*/
#include <linux/errno.h>
#include <linux/mm.h>
#include <asm/uaccess.h>
#include <asm/futex.h>
#include "uaccess.h"
#ifndef CONFIG_64BIT
#define AHI "ahi"
#define ALR "alr"
#define CLR "clr"
#define LHI "lhi"
#define SLR "slr"
#else
#define AHI "aghi"
#define ALR "algr"
#define CLR "clgr"
#define LHI "lghi"
#define SLR "slgr"
#endif
static size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x)
{
register unsigned long reg0 asm("0") = 0x81UL;
unsigned long tmp1, tmp2;
tmp1 = -4096UL;
asm volatile(
"0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n"
"9: jz 7f\n"
"1:"ALR" %0,%3\n"
" "SLR" %1,%3\n"
" "SLR" %2,%3\n"
" j 0b\n"
"2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */
" nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */
" "SLR" %4,%1\n"
" "CLR" %0,%4\n" /* copy crosses next page boundary? */
" jnh 4f\n"
"3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n"
"10:"SLR" %0,%4\n"
" "ALR" %2,%4\n"
"4:"LHI" %4,-1\n"
" "ALR" %4,%0\n" /* copy remaining size, subtract 1 */
" bras %3,6f\n" /* memset loop */
" xc 0(1,%2),0(%2)\n"
"5: xc 0(256,%2),0(%2)\n"
" la %2,256(%2)\n"
"6:"AHI" %4,-256\n"
" jnm 5b\n"
" ex %4,0(%3)\n"
" j 8f\n"
"7:"SLR" %0,%0\n"
"8: \n"
EX_TABLE(0b,2b) EX_TABLE(3b,4b) EX_TABLE(9b,2b) EX_TABLE(10b,4b)
: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
: "d" (reg0) : "cc", "memory");
return size;
}
static size_t copy_from_user_mvcos_check(size_t size, const void __user *ptr, void *x)
{
if (size <= 256)
return copy_from_user_std(size, ptr, x);
return copy_from_user_mvcos(size, ptr, x);
}
static size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x)
{
register unsigned long reg0 asm("0") = 0x810000UL;
unsigned long tmp1, tmp2;
tmp1 = -4096UL;
asm volatile(
"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
"6: jz 4f\n"
"1:"ALR" %0,%3\n"
" "SLR" %1,%3\n"
" "SLR" %2,%3\n"
" j 0b\n"
"2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */
" nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */
" "SLR" %4,%1\n"
" "CLR" %0,%4\n" /* copy crosses next page boundary? */
" jnh 5f\n"
"3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n"
"7:"SLR" %0,%4\n"
" j 5f\n"
"4:"SLR" %0,%0\n"
"5: \n"
EX_TABLE(0b,2b) EX_TABLE(3b,5b) EX_TABLE(6b,2b) EX_TABLE(7b,5b)
: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
: "d" (reg0) : "cc", "memory");
return size;
}
static size_t copy_to_user_mvcos_check(size_t size, void __user *ptr,
const void *x)
{
if (size <= 256)
return copy_to_user_std(size, ptr, x);
return copy_to_user_mvcos(size, ptr, x);
}
static size_t copy_in_user_mvcos(size_t size, void __user *to,
const void __user *from)
{
register unsigned long reg0 asm("0") = 0x810081UL;
unsigned long tmp1, tmp2;
tmp1 = -4096UL;
/* FIXME: copy with reduced length. */
asm volatile(
"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
" jz 2f\n"
"1:"ALR" %0,%3\n"
" "SLR" %1,%3\n"
" "SLR" %2,%3\n"
" j 0b\n"
"2:"SLR" %0,%0\n"
"3: \n"
EX_TABLE(0b,3b)
: "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
: "d" (reg0) : "cc", "memory");
return size;
}
static size_t clear_user_mvcos(size_t size, void __user *to)
{
register unsigned long reg0 asm("0") = 0x810000UL;
unsigned long tmp1, tmp2;
tmp1 = -4096UL;
asm volatile(
"0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n"
" jz 4f\n"
"1:"ALR" %0,%2\n"
" "SLR" %1,%2\n"
" j 0b\n"
"2: la %3,4095(%1)\n"/* %4 = to + 4095 */
" nr %3,%2\n" /* %4 = (to + 4095) & -4096 */
" "SLR" %3,%1\n"
" "CLR" %0,%3\n" /* copy crosses next page boundary? */
" jnh 5f\n"
"3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n"
" "SLR" %0,%3\n"
" j 5f\n"
"4:"SLR" %0,%0\n"
"5: \n"
EX_TABLE(0b,2b) EX_TABLE(3b,5b)
: "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2)
: "a" (empty_zero_page), "d" (reg0) : "cc", "memory");
return size;
}
static size_t strnlen_user_mvcos(size_t count, const char __user *src)
{
char buf[256];
int rc;
size_t done, len, len_str;
done = 0;
do {
len = min(count - done, (size_t) 256);
rc = uaccess.copy_from_user(len, src + done, buf);
if (unlikely(rc == len))
return 0;
len -= rc;
len_str = strnlen(buf, len);
done += len_str;
} while ((len_str == len) && (done < count));
return done + 1;
}
static size_t strncpy_from_user_mvcos(size_t count, const char __user *src,
char *dst)
{
int rc;
size_t done, len, len_str;
done = 0;
do {
len = min(count - done, (size_t) 4096);
rc = uaccess.copy_from_user(len, src + done, dst);
if (unlikely(rc == len))
return -EFAULT;
len -= rc;
len_str = strnlen(dst, len);
done += len_str;
} while ((len_str == len) && (done < count));
return done;
}
struct uaccess_ops uaccess_mvcos = {
.copy_from_user = copy_from_user_mvcos_check,
.copy_from_user_small = copy_from_user_std,
.copy_to_user = copy_to_user_mvcos_check,
.copy_to_user_small = copy_to_user_std,
.copy_in_user = copy_in_user_mvcos,
.clear_user = clear_user_mvcos,
.strnlen_user = strnlen_user_std,
.strncpy_from_user = strncpy_from_user_std,
.futex_atomic_op = futex_atomic_op_std,
.futex_atomic_cmpxchg = futex_atomic_cmpxchg_std,
};
struct uaccess_ops uaccess_mvcos_switch = {
.copy_from_user = copy_from_user_mvcos,
.copy_from_user_small = copy_from_user_mvcos,
.copy_to_user = copy_to_user_mvcos,
.copy_to_user_small = copy_to_user_mvcos,
.copy_in_user = copy_in_user_mvcos,
.clear_user = clear_user_mvcos,
.strnlen_user = strnlen_user_mvcos,
.strncpy_from_user = strncpy_from_user_mvcos,
.futex_atomic_op = futex_atomic_op_pt,
.futex_atomic_cmpxchg = futex_atomic_cmpxchg_pt,
};