summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorVineet Gupta <vgupta@synopsys.com>2013-01-18 15:12:16 +0530
committerVineet Gupta <vgupta@synopsys.com>2013-02-11 20:00:31 +0530
commit43697cb0973da144156e7d11ddd035aee226ee30 (patch)
tree8c2d6bd2541e536ccd5d04dc2e1b0c7dd5adb66a
parent10a6007bda48e3524e24ce1ad46dc7be1add6a0e (diff)
ARC: uaccess friends
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
-rw-r--r--arch/arc/include/asm/segment.h24
-rw-r--r--arch/arc/include/asm/uaccess.h646
-rw-r--r--arch/arc/mm/extable.c63
3 files changed, 733 insertions, 0 deletions
diff --git a/arch/arc/include/asm/segment.h b/arch/arc/include/asm/segment.h
new file mode 100644
index 000000000000..da2c45979817
--- /dev/null
+++ b/arch/arc/include/asm/segment.h
@@ -0,0 +1,24 @@
+/*
+ * 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.
+ */
+
+#ifndef __ASMARC_SEGMENT_H
+#define __ASMARC_SEGMENT_H
+
+#ifndef __ASSEMBLY__
+
+typedef unsigned long mm_segment_t;
+
+#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
+
+#define KERNEL_DS MAKE_MM_SEG(0)
+#define USER_DS MAKE_MM_SEG(TASK_SIZE)
+
+#define segment_eq(a, b) ((a) == (b))
+
+#endif /* __ASSEMBLY__ */
+#endif /* __ASMARC_SEGMENT_H */
diff --git a/arch/arc/include/asm/uaccess.h b/arch/arc/include/asm/uaccess.h
new file mode 100644
index 000000000000..f13bca44f27a
--- /dev/null
+++ b/arch/arc/include/asm/uaccess.h
@@ -0,0 +1,646 @@
+/*
+ * 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.
+ *
+ * vineetg: Dec 2009
+ * -Hand crafted constant propagation for "constant" copy sizes
+ * -stock kernel shrunk by 33K at -O3
+ *
+ * vineetg: Sept 2009
+ * -Added option to (UN)inline copy_(to|from)_user to reduce code sz
+ * -kernel shrunk by 200K even at -O3 (gcc 4.2.1)
+ * -Enabled when doing -Os
+ *
+ * Amit Bhor, Sameer Dhavale: Codito Technologies 2004
+ */
+
+#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))))
+
+static inline unsigned long
+__arc_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ long res = 0;
+ char val;
+ unsigned long tmp1, tmp2, tmp3, tmp4;
+ unsigned long orig_n = n;
+
+ if (n == 0)
+ return 0;
+
+ /* unaligned */
+ if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
+
+ unsigned char tmp;
+
+ __asm__ __volatile__ (
+ " mov.f lp_count, %0 \n"
+ " lpnz 2f \n"
+ "1: ldb.ab %1, [%3, 1] \n"
+ " stb.ab %1, [%2, 1] \n"
+ " sub %0,%0,1 \n"
+ "2: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "3: j 2b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 1b, 3b \n"
+ " .previous \n"
+
+ : "+r" (n),
+ /*
+ * Note as an '&' earlyclobber operand to make sure the
+ * temporary register inside the loop is not the same as
+ * FROM or TO.
+ */
+ "=&r" (tmp), "+r" (to), "+r" (from)
+ :
+ : "lp_count", "lp_start", "lp_end", "memory");
+
+ return n;
+ }
+
+ /*
+ * Hand-crafted constant propagation to reduce code sz of the
+ * laddered copy 16x,8,4,2,1
+ */
+ if (__builtin_constant_p(orig_n)) {
+ res = orig_n;
+
+ if (orig_n / 16) {
+ orig_n = orig_n % 16;
+
+ __asm__ __volatile__(
+ " lsr lp_count, %7,4 \n"
+ " lp 3f \n"
+ "1: ld.ab %3, [%2, 4] \n"
+ "11: ld.ab %4, [%2, 4] \n"
+ "12: ld.ab %5, [%2, 4] \n"
+ "13: ld.ab %6, [%2, 4] \n"
+ " st.ab %3, [%1, 4] \n"
+ " st.ab %4, [%1, 4] \n"
+ " st.ab %5, [%1, 4] \n"
+ " st.ab %6, [%1, 4] \n"
+ " sub %0,%0,16 \n"
+ "3: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 3b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 1b, 4b \n"
+ " .word 11b,4b \n"
+ " .word 12b,4b \n"
+ " .word 13b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from),
+ "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
+ : "ir"(n)
+ : "lp_count", "memory");
+ }
+ if (orig_n / 8) {
+ orig_n = orig_n % 8;
+
+ __asm__ __volatile__(
+ "14: ld.ab %3, [%2,4] \n"
+ "15: ld.ab %4, [%2,4] \n"
+ " st.ab %3, [%1,4] \n"
+ " st.ab %4, [%1,4] \n"
+ " sub %0,%0,8 \n"
+ "31: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 31b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 14b,4b \n"
+ " .word 15b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from),
+ "=r"(tmp1), "=r"(tmp2)
+ :
+ : "memory");
+ }
+ if (orig_n / 4) {
+ orig_n = orig_n % 4;
+
+ __asm__ __volatile__(
+ "16: ld.ab %3, [%2,4] \n"
+ " st.ab %3, [%1,4] \n"
+ " sub %0,%0,4 \n"
+ "32: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 32b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 16b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
+ :
+ : "memory");
+ }
+ if (orig_n / 2) {
+ orig_n = orig_n % 2;
+
+ __asm__ __volatile__(
+ "17: ldw.ab %3, [%2,2] \n"
+ " stw.ab %3, [%1,2] \n"
+ " sub %0,%0,2 \n"
+ "33: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 33b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 17b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
+ :
+ : "memory");
+ }
+ if (orig_n & 1) {
+ __asm__ __volatile__(
+ "18: ldb.ab %3, [%2,2] \n"
+ " stb.ab %3, [%1,2] \n"
+ " sub %0,%0,1 \n"
+ "34: ; nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 34b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 18b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
+ :
+ : "memory");
+ }
+ } else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */
+
+ __asm__ __volatile__(
+ " mov %0,%3 \n"
+ " lsr.f lp_count, %3,4 \n" /* 16x bytes */
+ " lpnz 3f \n"
+ "1: ld.ab %5, [%2, 4] \n"
+ "11: ld.ab %6, [%2, 4] \n"
+ "12: ld.ab %7, [%2, 4] \n"
+ "13: ld.ab %8, [%2, 4] \n"
+ " st.ab %5, [%1, 4] \n"
+ " st.ab %6, [%1, 4] \n"
+ " st.ab %7, [%1, 4] \n"
+ " st.ab %8, [%1, 4] \n"
+ " sub %0,%0,16 \n"
+ "3: and.f %3,%3,0xf \n" /* stragglers */
+ " bz 34f \n"
+ " bbit0 %3,3,31f \n" /* 8 bytes left */
+ "14: ld.ab %5, [%2,4] \n"
+ "15: ld.ab %6, [%2,4] \n"
+ " st.ab %5, [%1,4] \n"
+ " st.ab %6, [%1,4] \n"
+ " sub.f %0,%0,8 \n"
+ "31: bbit0 %3,2,32f \n" /* 4 bytes left */
+ "16: ld.ab %5, [%2,4] \n"
+ " st.ab %5, [%1,4] \n"
+ " sub.f %0,%0,4 \n"
+ "32: bbit0 %3,1,33f \n" /* 2 bytes left */
+ "17: ldw.ab %5, [%2,2] \n"
+ " stw.ab %5, [%1,2] \n"
+ " sub.f %0,%0,2 \n"
+ "33: bbit0 %3,0,34f \n"
+ "18: ldb.ab %5, [%2,1] \n" /* 1 byte left */
+ " stb.ab %5, [%1,1] \n"
+ " sub.f %0,%0,1 \n"
+ "34: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 34b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 1b, 4b \n"
+ " .word 11b,4b \n"
+ " .word 12b,4b \n"
+ " .word 13b,4b \n"
+ " .word 14b,4b \n"
+ " .word 15b,4b \n"
+ " .word 16b,4b \n"
+ " .word 17b,4b \n"
+ " .word 18b,4b \n"
+ " .previous \n"
+ : "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
+ "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
+ :
+ : "lp_count", "memory");
+ }
+
+ 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)
+{
+ long res = 0;
+ char val;
+ unsigned long tmp1, tmp2, tmp3, tmp4;
+ unsigned long orig_n = n;
+
+ if (n == 0)
+ return 0;
+
+ /* unaligned */
+ if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
+
+ unsigned char tmp;
+
+ __asm__ __volatile__(
+ " mov.f lp_count, %0 \n"
+ " lpnz 3f \n"
+ " ldb.ab %1, [%3, 1] \n"
+ "1: stb.ab %1, [%2, 1] \n"
+ " sub %0, %0, 1 \n"
+ "3: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 3b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 1b, 4b \n"
+ " .previous \n"
+
+ : "+r" (n),
+ /* Note as an '&' earlyclobber operand to make sure the
+ * temporary register inside the loop is not the same as
+ * FROM or TO.
+ */
+ "=&r" (tmp), "+r" (to), "+r" (from)
+ :
+ : "lp_count", "lp_start", "lp_end", "memory");
+
+ return n;
+ }
+
+ if (__builtin_constant_p(orig_n)) {
+ res = orig_n;
+
+ if (orig_n / 16) {
+ orig_n = orig_n % 16;
+
+ __asm__ __volatile__(
+ " lsr lp_count, %7,4 \n"
+ " lp 3f \n"
+ " ld.ab %3, [%2, 4] \n"
+ " ld.ab %4, [%2, 4] \n"
+ " ld.ab %5, [%2, 4] \n"
+ " ld.ab %6, [%2, 4] \n"
+ "1: st.ab %3, [%1, 4] \n"
+ "11: st.ab %4, [%1, 4] \n"
+ "12: st.ab %5, [%1, 4] \n"
+ "13: st.ab %6, [%1, 4] \n"
+ " sub %0, %0, 16 \n"
+ "3:;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 3b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 1b, 4b \n"
+ " .word 11b,4b \n"
+ " .word 12b,4b \n"
+ " .word 13b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from),
+ "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
+ : "ir"(n)
+ : "lp_count", "memory");
+ }
+ if (orig_n / 8) {
+ orig_n = orig_n % 8;
+
+ __asm__ __volatile__(
+ " ld.ab %3, [%2,4] \n"
+ " ld.ab %4, [%2,4] \n"
+ "14: st.ab %3, [%1,4] \n"
+ "15: st.ab %4, [%1,4] \n"
+ " sub %0, %0, 8 \n"
+ "31:;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 31b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 14b,4b \n"
+ " .word 15b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from),
+ "=r"(tmp1), "=r"(tmp2)
+ :
+ : "memory");
+ }
+ if (orig_n / 4) {
+ orig_n = orig_n % 4;
+
+ __asm__ __volatile__(
+ " ld.ab %3, [%2,4] \n"
+ "16: st.ab %3, [%1,4] \n"
+ " sub %0, %0, 4 \n"
+ "32:;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 32b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 16b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
+ :
+ : "memory");
+ }
+ if (orig_n / 2) {
+ orig_n = orig_n % 2;
+
+ __asm__ __volatile__(
+ " ldw.ab %3, [%2,2] \n"
+ "17: stw.ab %3, [%1,2] \n"
+ " sub %0, %0, 2 \n"
+ "33:;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 33b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 17b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
+ :
+ : "memory");
+ }
+ if (orig_n & 1) {
+ __asm__ __volatile__(
+ " ldb.ab %3, [%2,1] \n"
+ "18: stb.ab %3, [%1,1] \n"
+ " sub %0, %0, 1 \n"
+ "34: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 34b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 18b,4b \n"
+ " .previous \n"
+ : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
+ :
+ : "memory");
+ }
+ } else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */
+
+ __asm__ __volatile__(
+ " mov %0,%3 \n"
+ " lsr.f lp_count, %3,4 \n" /* 16x bytes */
+ " lpnz 3f \n"
+ " ld.ab %5, [%2, 4] \n"
+ " ld.ab %6, [%2, 4] \n"
+ " ld.ab %7, [%2, 4] \n"
+ " ld.ab %8, [%2, 4] \n"
+ "1: st.ab %5, [%1, 4] \n"
+ "11: st.ab %6, [%1, 4] \n"
+ "12: st.ab %7, [%1, 4] \n"
+ "13: st.ab %8, [%1, 4] \n"
+ " sub %0, %0, 16 \n"
+ "3: and.f %3,%3,0xf \n" /* stragglers */
+ " bz 34f \n"
+ " bbit0 %3,3,31f \n" /* 8 bytes left */
+ " ld.ab %5, [%2,4] \n"
+ " ld.ab %6, [%2,4] \n"
+ "14: st.ab %5, [%1,4] \n"
+ "15: st.ab %6, [%1,4] \n"
+ " sub.f %0, %0, 8 \n"
+ "31: bbit0 %3,2,32f \n" /* 4 bytes left */
+ " ld.ab %5, [%2,4] \n"
+ "16: st.ab %5, [%1,4] \n"
+ " sub.f %0, %0, 4 \n"
+ "32: bbit0 %3,1,33f \n" /* 2 bytes left */
+ " ldw.ab %5, [%2,2] \n"
+ "17: stw.ab %5, [%1,2] \n"
+ " sub.f %0, %0, 2 \n"
+ "33: bbit0 %3,0,34f \n"
+ " ldb.ab %5, [%2,1] \n" /* 1 byte left */
+ "18: stb.ab %5, [%1,1] \n"
+ " sub.f %0, %0, 1 \n"
+ "34: ;nop \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "4: j 34b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 1b, 4b \n"
+ " .word 11b,4b \n"
+ " .word 12b,4b \n"
+ " .word 13b,4b \n"
+ " .word 14b,4b \n"
+ " .word 15b,4b \n"
+ " .word 16b,4b \n"
+ " .word 17b,4b \n"
+ " .word 18b,4b \n"
+ " .previous \n"
+ : "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
+ "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
+ :
+ : "lp_count", "memory");
+ }
+
+ return res;
+}
+
+static inline unsigned long __arc_clear_user(void __user *to, unsigned long n)
+{
+ long res = n;
+ unsigned char *d_char = to;
+
+ __asm__ __volatile__(
+ " bbit0 %0, 0, 1f \n"
+ "75: stb.ab %2, [%0,1] \n"
+ " sub %1, %1, 1 \n"
+ "1: bbit0 %0, 1, 2f \n"
+ "76: stw.ab %2, [%0,2] \n"
+ " sub %1, %1, 2 \n"
+ "2: asr.f lp_count, %1, 2 \n"
+ " lpnz 3f \n"
+ "77: st.ab %2, [%0,4] \n"
+ " sub %1, %1, 4 \n"
+ "3: bbit0 %1, 1, 4f \n"
+ "78: stw.ab %2, [%0,2] \n"
+ " sub %1, %1, 2 \n"
+ "4: bbit0 %1, 0, 5f \n"
+ "79: stb.ab %2, [%0,1] \n"
+ " sub %1, %1, 1 \n"
+ "5: \n"
+ " .section .fixup, \"ax\" \n"
+ " .align 4 \n"
+ "3: j 5b \n"
+ " .previous \n"
+ " .section __ex_table, \"a\" \n"
+ " .align 4 \n"
+ " .word 75b, 3b \n"
+ " .word 76b, 3b \n"
+ " .word 77b, 3b \n"
+ " .word 78b, 3b \n"
+ " .word 79b, 3b \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");
+
+ 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)
+
+#endif
+
+#include <asm-generic/uaccess.h>
+
+extern int fixup_exception(struct pt_regs *regs);
+
+#endif
diff --git a/arch/arc/mm/extable.c b/arch/arc/mm/extable.c
new file mode 100644
index 000000000000..014172ba8432
--- /dev/null
+++ b/arch/arc/mm/extable.c
@@ -0,0 +1,63 @@
+/*
+ * 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.
+ *
+ * Borrowed heavily from MIPS
+ */
+
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+int fixup_exception(struct pt_regs *regs)
+{
+ const struct exception_table_entry *fixup;
+
+ fixup = search_exception_tables(instruction_pointer(regs));
+ if (fixup) {
+ regs->ret = fixup->fixup;
+
+ return 1;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
+
+long arc_copy_from_user_noinline(void *to, const void __user * from,
+ unsigned long n)
+{
+ return __arc_copy_from_user(to, from, n);
+}
+EXPORT_SYMBOL(arc_copy_from_user_noinline);
+
+long arc_copy_to_user_noinline(void __user *to, const void *from,
+ unsigned long n)
+{
+ return __arc_copy_to_user(to, from, n);
+}
+EXPORT_SYMBOL(arc_copy_to_user_noinline);
+
+unsigned long arc_clear_user_noinline(void __user *to,
+ unsigned long n)
+{
+ return __arc_clear_user(to, n);
+}
+EXPORT_SYMBOL(arc_clear_user_noinline);
+
+long arc_strncpy_from_user_noinline (char *dst, const char __user *src,
+ long count)
+{
+ return __arc_strncpy_from_user(dst, src, count);
+}
+EXPORT_SYMBOL(arc_strncpy_from_user_noinline);
+
+long arc_strnlen_user_noinline(const char __user *src, long n)
+{
+ return __arc_strnlen_user(src, n);
+}
+EXPORT_SYMBOL(arc_strnlen_user_noinline);
+#endif