linux/arch/sparc/include/asm/uaccess_32.h
Andreas Larsson a7ec177ebc sparc32: Fix truncated relocation errors when linking large kernels
Use jumps instead of branches when jumping from one section to another
to avoid branches to addresses further away than 22 bit offsets can
handle that results in errors such as

arch/sparc/kernel/signal_32.o:(.fixup+0x0): relocation truncated to fit: R_SPARC_WDISP22 against `.text'

This is the same approach that was taken for sparc64 in commit
52eb053b71 ("[SPARC64]: Fix linkage of enormous kernels.")

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202405080936.tWaJdO3P-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202406240441.5zaoshVX-lkp@intel.com/
Link: https://lore.kernel.org/r/20240710092341.457591-1-andreas@gaisler.com
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
2024-07-11 15:58:18 +02:00

222 lines
6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* uaccess.h: User space memore access functions.
*
* Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H
#include <linux/compiler.h>
#include <linux/string.h>
#include <asm/processor.h>
#include <asm-generic/access_ok.h>
/* Uh, these should become the main single-value transfer routines..
* They automatically use the right size if we just have the right
* pointer type..
*
* This gets kind of ugly. We want to return _two_ values in "get_user()"
* and yet we don't want to do any pointers, because that is too much
* of a performance impact. Thus we have a few rather ugly macros here,
* and hide all the ugliness from the user.
*/
#define put_user(x, ptr) ({ \
void __user *__pu_addr = (ptr); \
__chk_user_ptr(ptr); \
__put_user_check((__typeof__(*(ptr)))(x), __pu_addr, sizeof(*(ptr))); \
})
#define get_user(x, ptr) ({ \
const void __user *__gu_addr = (ptr); \
__chk_user_ptr(ptr); \
__get_user_check((x), __gu_addr, sizeof(*(ptr)), __typeof__(*(ptr))); \
})
/*
* The "__xxx" versions do not do address space checking, useful when
* doing multiple accesses to the same area (the user has to do the
* checks by hand with "access_ok()")
*/
#define __put_user(x, ptr) \
__put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
#define __get_user(x, ptr) \
__get_user_nocheck((x), (ptr), sizeof(*(ptr)), __typeof__(*(ptr)))
struct __large_struct { unsigned long buf[100]; };
#define __m(x) ((struct __large_struct __user *)(x))
#define __put_user_check(x, addr, size) ({ \
register int __pu_ret; \
if (__access_ok(addr, size)) { \
switch (size) { \
case 1: \
__put_user_asm(x, b, addr, __pu_ret); \
break; \
case 2: \
__put_user_asm(x, h, addr, __pu_ret); \
break; \
case 4: \
__put_user_asm(x, , addr, __pu_ret); \
break; \
case 8: \
__put_user_asm(x, d, addr, __pu_ret); \
break; \
default: \
__pu_ret = __put_user_bad(); \
break; \
} \
} else { \
__pu_ret = -EFAULT; \
} \
__pu_ret; \
})
#define __put_user_nocheck(x, addr, size) ({ \
register int __pu_ret; \
switch (size) { \
case 1: __put_user_asm(x, b, addr, __pu_ret); break; \
case 2: __put_user_asm(x, h, addr, __pu_ret); break; \
case 4: __put_user_asm(x, , addr, __pu_ret); break; \
case 8: __put_user_asm(x, d, addr, __pu_ret); break; \
default: __pu_ret = __put_user_bad(); break; \
} \
__pu_ret; \
})
#define __put_user_asm(x, size, addr, ret) \
__asm__ __volatile__( \
"/* Put user asm, inline. */\n" \
"1:\t" "st"#size " %1, %2\n\t" \
"clr %0\n" \
"2:\n\n\t" \
".section .fixup,#alloc,#execinstr\n\t" \
".align 4\n" \
"3:\n\t" \
"sethi %%hi(2b), %0\n\t" \
"jmpl %0 + %%lo(2b), %%g0\n\t" \
" mov %3, %0\n\t" \
".previous\n\n\t" \
".section __ex_table,#alloc\n\t" \
".align 4\n\t" \
".word 1b, 3b\n\t" \
".previous\n\n\t" \
: "=&r" (ret) : "r" (x), "m" (*__m(addr)), \
"i" (-EFAULT))
int __put_user_bad(void);
#define __get_user_check(x, addr, size, type) ({ \
register int __gu_ret; \
register unsigned long __gu_val; \
if (__access_ok(addr, size)) { \
switch (size) { \
case 1: \
__get_user_asm(__gu_val, ub, addr, __gu_ret); \
break; \
case 2: \
__get_user_asm(__gu_val, uh, addr, __gu_ret); \
break; \
case 4: \
__get_user_asm(__gu_val, , addr, __gu_ret); \
break; \
case 8: \
__get_user_asm(__gu_val, d, addr, __gu_ret); \
break; \
default: \
__gu_val = 0; \
__gu_ret = __get_user_bad(); \
break; \
} \
} else { \
__gu_val = 0; \
__gu_ret = -EFAULT; \
} \
x = (__force type) __gu_val; \
__gu_ret; \
})
#define __get_user_nocheck(x, addr, size, type) ({ \
register int __gu_ret; \
register unsigned long __gu_val; \
switch (size) { \
case 1: __get_user_asm(__gu_val, ub, addr, __gu_ret); break; \
case 2: __get_user_asm(__gu_val, uh, addr, __gu_ret); break; \
case 4: __get_user_asm(__gu_val, , addr, __gu_ret); break; \
case 8: __get_user_asm(__gu_val, d, addr, __gu_ret); break; \
default: \
__gu_val = 0; \
__gu_ret = __get_user_bad(); \
break; \
} \
x = (__force type) __gu_val; \
__gu_ret; \
})
#define __get_user_asm(x, size, addr, ret) \
__asm__ __volatile__( \
"/* Get user asm, inline. */\n" \
"1:\t" "ld"#size " %2, %1\n\t" \
"clr %0\n" \
"2:\n\n\t" \
".section .fixup,#alloc,#execinstr\n\t" \
".align 4\n" \
"3:\n\t" \
"sethi %%hi(2b), %0\n\t" \
"clr %1\n\t" \
"jmpl %0 + %%lo(2b), %%g0\n\t" \
" mov %3, %0\n\n\t" \
".previous\n\t" \
".section __ex_table,#alloc\n\t" \
".align 4\n\t" \
".word 1b, 3b\n\n\t" \
".previous\n\t" \
: "=&r" (ret), "=&r" (x) : "m" (*__m(addr)), \
"i" (-EFAULT))
int __get_user_bad(void);
unsigned long __copy_user(void __user *to, const void __user *from, unsigned long size);
static inline unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
return __copy_user(to, (__force void __user *) from, n);
}
static inline unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
return __copy_user((__force void __user *) to, from, n);
}
#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER
static inline unsigned long __clear_user(void __user *addr, unsigned long size)
{
unsigned long ret;
__asm__ __volatile__ (
"mov %2, %%o1\n"
"call __bzero\n\t"
" mov %1, %%o0\n\t"
"mov %%o0, %0\n"
: "=r" (ret) : "r" (addr), "r" (size) :
"o0", "o1", "o2", "o3", "o4", "o5", "o7",
"g1", "g2", "g3", "g4", "g5", "g7", "cc");
return ret;
}
static inline unsigned long clear_user(void __user *addr, unsigned long n)
{
if (n && __access_ok(addr, n))
return __clear_user(addr, n);
else
return n;
}
__must_check long strnlen_user(const char __user *str, long n);
#endif /* _ASM_UACCESS_H */