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+/*
+ * linux/arch/arm/lib/getuser.S
+ *
+ * Copyright (C) 2001 Russell King
+ *
+ * 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.
+ *
+ * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
+ *
+ * These functions have a non-standard call interface to make them more
+ * efficient, especially as they return an error value in addition to
+ * the "real" return value.
+ *
+ * __get_user_X
+ *
+ * Inputs: r0 contains the address
+ * Outputs: r0 is the error code
+ * r2, r3 contains the zero-extended value
+ * lr corrupted
+ *
+ * No other registers must be altered. (see include/asm-arm/uaccess.h
+ * for specific ASM register usage).
+ *
+ * Note that ADDR_LIMIT is either 0 or 0xc0000000.
+ * Note also that it is intended that __get_user_bad is not global.
+ */
+#include <asm/constants.h>
+#include <asm/thread_info.h>
+#include <asm/errno.h>
+
+ .global __get_user_1
+__get_user_1:
+1: ldrbt r2, [r0]
+ mov r0, #0
+ mov pc, lr
+
+ .global __get_user_2
+__get_user_2:
+2: ldrbt r2, [r0], #1
+3: ldrbt r3, [r0]
+#ifndef __ARMEB__
+ orr r2, r2, r3, lsl #8
+#else
+ orr r2, r3, r2, lsl #8
+#endif
+ mov r0, #0
+ mov pc, lr
+
+ .global __get_user_4
+__get_user_4:
+4: ldrt r2, [r0]
+ mov r0, #0
+ mov pc, lr
+
+ .global __get_user_8
+__get_user_8:
+5: ldrt r2, [r0], #4
+6: ldrt r3, [r0]
+ mov r0, #0
+ mov pc, lr
+
+__get_user_bad_8:
+ mov r3, #0
+__get_user_bad:
+ mov r2, #0
+ mov r0, #-EFAULT
+ mov pc, lr
+
+.section __ex_table, "a"
+ .long 1b, __get_user_bad
+ .long 2b, __get_user_bad
+ .long 3b, __get_user_bad
+ .long 4b, __get_user_bad
+ .long 5b, __get_user_bad_8
+ .long 6b, __get_user_bad_8
+.previous