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Diffstat (limited to 'arch/arc/include/asm/uaccess.h')
-rw-r--r--arch/arc/include/asm/uaccess.h163
1 files changed, 25 insertions, 138 deletions
diff --git a/arch/arc/include/asm/uaccess.h b/arch/arc/include/asm/uaccess.h
index 32420824375b..1e8809ea000a 100644
--- a/arch/arc/include/asm/uaccess.h
+++ b/arch/arc/include/asm/uaccess.h
@@ -1,10 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
* vineetg: June 2010
* -__clear_user( ) called multiple times during elf load was byte loop
* converted to do as much word clear as possible.
@@ -24,39 +21,8 @@
#ifndef _ASM_ARC_UACCESS_H
#define _ASM_ARC_UACCESS_H
-#include <linux/sched.h>
-#include <asm/errno.h>
#include <linux/string.h> /* for generic string functions */
-
-#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
-
-/*
- * Algorthmically, for __user_ok() we want do:
- * (start < TASK_SIZE) && (start+len < TASK_SIZE)
- * where TASK_SIZE could either be retrieved from thread_info->addr_limit or
- * emitted directly in code.
- *
- * This can however be rewritten as follows:
- * (len <= TASK_SIZE) && (start+len < TASK_SIZE)
- *
- * Because it essentially checks if buffer end is within limit and @len is
- * non-ngeative, which implies that buffer start will be within limit too.
- *
- * The reason for rewriting being, for majorit yof cases, @len is generally
- * compile time constant, causing first sub-expression to be compile time
- * subsumed.
- *
- * The second part would generate weird large LIMMs e.g. (0x6000_0000 - 0x10),
- * so we check for TASK_SIZE using get_fs() since the addr_limit load from mem
- * would already have been done at this call site for __kernel_ok()
- *
- */
-#define __user_ok(addr, sz) (((sz) <= TASK_SIZE) && \
- (((addr)+(sz)) <= get_fs()))
-#define __access_ok(addr, sz) (unlikely(__kernel_ok) || \
- likely(__user_ok((addr), (sz))))
-
/*********** Single byte/hword/word copies ******************/
#define __get_user_fn(sz, u, k) \
@@ -83,7 +49,10 @@
"2: ;nop\n" \
" .section .fixup, \"ax\"\n" \
" .align 4\n" \
- "3: mov %0, %3\n" \
+ "3: # return -EFAULT\n" \
+ " mov %0, %3\n" \
+ " # zero out dst ptr\n" \
+ " mov %1, 0\n" \
" j 2b\n" \
" .previous\n" \
" .section __ex_table, \"a\"\n" \
@@ -101,7 +70,11 @@
"2: ;nop\n" \
" .section .fixup, \"ax\"\n" \
" .align 4\n" \
- "3: mov %0, %3\n" \
+ "3: # return -EFAULT\n" \
+ " mov %0, %3\n" \
+ " # zero out dst ptr\n" \
+ " mov %1, 0\n" \
+ " mov %R1, 0\n" \
" j 2b\n" \
" .previous\n" \
" .section __ex_table, \"a\"\n" \
@@ -163,7 +136,7 @@
static inline unsigned long
-__arc_copy_from_user(void *to, const void __user *from, unsigned long n)
+raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
long res = 0;
char val;
@@ -173,8 +146,9 @@ __arc_copy_from_user(void *to, const void __user *from, unsigned long n)
if (n == 0)
return 0;
- /* unaligned */
- if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
+ /* fallback for unaligned access when hardware doesn't support */
+ if (!IS_ENABLED(CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS) &&
+ (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3))) {
unsigned char tmp;
@@ -202,7 +176,7 @@ __arc_copy_from_user(void *to, const void __user *from, unsigned long n)
*/
"=&r" (tmp), "+r" (to), "+r" (from)
:
- : "lp_count", "lp_start", "lp_end", "memory");
+ : "lp_count", "memory");
return n;
}
@@ -389,11 +363,8 @@ __arc_copy_from_user(void *to, const void __user *from, unsigned long n)
return res;
}
-extern unsigned long slowpath_copy_to_user(void __user *to, const void *from,
- unsigned long n);
-
static inline unsigned long
-__arc_copy_to_user(void __user *to, const void *from, unsigned long n)
+raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
long res = 0;
char val;
@@ -403,8 +374,9 @@ __arc_copy_to_user(void __user *to, const void *from, unsigned long n)
if (n == 0)
return 0;
- /* unaligned */
- if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
+ /* fallback for unaligned access when hardware doesn't support */
+ if (!IS_ENABLED(CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS) &&
+ (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3))) {
unsigned char tmp;
@@ -431,7 +403,7 @@ __arc_copy_to_user(void __user *to, const void *from, unsigned long n)
*/
"=&r" (tmp), "+r" (to), "+r" (from)
:
- : "lp_count", "lp_start", "lp_end", "memory");
+ : "lp_count", "memory");
return n;
}
@@ -614,7 +586,7 @@ __arc_copy_to_user(void __user *to, const void *from, unsigned long n)
return res;
}
-static inline unsigned long __arc_clear_user(void __user *to, unsigned long n)
+static inline unsigned long __clear_user(void __user *to, unsigned long n)
{
long res = n;
unsigned char *d_char = to;
@@ -651,101 +623,16 @@ static inline unsigned long __arc_clear_user(void __user *to, unsigned long n)
" .previous \n"
: "+r"(d_char), "+r"(res)
: "i"(0)
- : "lp_count", "lp_start", "lp_end", "memory");
-
- return res;
-}
-
-static inline long
-__arc_strncpy_from_user(char *dst, const char __user *src, long count)
-{
- long res = count;
- char val;
- unsigned int hw_count;
-
- if (count == 0)
- return 0;
-
- __asm__ __volatile__(
- " lp 2f \n"
- "1: ldb.ab %3, [%2, 1] \n"
- " breq.d %3, 0, 2f \n"
- " stb.ab %3, [%1, 1] \n"
- "2: sub %0, %6, %4 \n"
- "3: ;nop \n"
- " .section .fixup, \"ax\" \n"
- " .align 4 \n"
- "4: mov %0, %5 \n"
- " j 3b \n"
- " .previous \n"
- " .section __ex_table, \"a\" \n"
- " .align 4 \n"
- " .word 1b, 4b \n"
- " .previous \n"
- : "=r"(res), "+r"(dst), "+r"(src), "=&r"(val), "=l"(hw_count)
- : "g"(-EFAULT), "ir"(count), "4"(count) /* this "4" seeds lp_count */
- : "memory");
-
- return res;
-}
-
-static inline long __arc_strnlen_user(const char __user *s, long n)
-{
- long res, tmp1, cnt;
- char val;
-
- __asm__ __volatile__(
- " mov %2, %1 \n"
- "1: ldb.ab %3, [%0, 1] \n"
- " breq.d %3, 0, 2f \n"
- " sub.f %2, %2, 1 \n"
- " bnz 1b \n"
- " sub %2, %2, 1 \n"
- "2: sub %0, %1, %2 \n"
- "3: ;nop \n"
- " .section .fixup, \"ax\" \n"
- " .align 4 \n"
- "4: mov %0, 0 \n"
- " j 3b \n"
- " .previous \n"
- " .section __ex_table, \"a\" \n"
- " .align 4 \n"
- " .word 1b, 4b \n"
- " .previous \n"
- : "=r"(res), "=r"(tmp1), "=r"(cnt), "=r"(val)
- : "0"(s), "1"(n)
- : "memory");
+ : "lp_count", "memory");
return res;
}
-#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
-#define __copy_from_user(t, f, n) __arc_copy_from_user(t, f, n)
-#define __copy_to_user(t, f, n) __arc_copy_to_user(t, f, n)
-#define __clear_user(d, n) __arc_clear_user(d, n)
-#define __strncpy_from_user(d, s, n) __arc_strncpy_from_user(d, s, n)
-#define __strnlen_user(s, n) __arc_strnlen_user(s, n)
-#else
-extern long arc_copy_from_user_noinline(void *to, const void __user * from,
- unsigned long n);
-extern long arc_copy_to_user_noinline(void __user *to, const void *from,
- unsigned long n);
-extern unsigned long arc_clear_user_noinline(void __user *to,
- unsigned long n);
-extern long arc_strncpy_from_user_noinline (char *dst, const char __user *src,
- long count);
-extern long arc_strnlen_user_noinline(const char __user *src, long n);
-
-#define __copy_from_user(t, f, n) arc_copy_from_user_noinline(t, f, n)
-#define __copy_to_user(t, f, n) arc_copy_to_user_noinline(t, f, n)
-#define __clear_user(d, n) arc_clear_user_noinline(d, n)
-#define __strncpy_from_user(d, s, n) arc_strncpy_from_user_noinline(d, s, n)
-#define __strnlen_user(s, n) arc_strnlen_user_noinline(s, n)
+#define INLINE_COPY_TO_USER
+#define INLINE_COPY_FROM_USER
-#endif
+#define __clear_user __clear_user
#include <asm-generic/uaccess.h>
-extern int fixup_exception(struct pt_regs *regs);
-
#endif
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