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+/*
+ * linux/arch/arm/lib/putuser.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.
+ *
+ * __put_user_X
+ *
+ * Inputs: r0 contains the address
+ * r2, r3 contains the value
+ * Outputs: r0 is the error code
+ * 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 __put_user_bad is not global.
+ */
+#include <asm/constants.h>
+#include <asm/thread_info.h>
+#include <asm/errno.h>
+
+ .global __put_user_1
+__put_user_1:
+1: strbt r2, [r0]
+ mov r0, #0
+ mov pc, lr
+
+ .global __put_user_2
+__put_user_2:
+ mov ip, r2, lsr #8
+#ifndef __ARMEB__
+2: strbt r2, [r0], #1
+3: strbt ip, [r0]
+#else
+2: strbt ip, [r0], #1
+3: strbt r2, [r0]
+#endif
+ mov r0, #0
+ mov pc, lr
+
+ .global __put_user_4
+__put_user_4:
+4: strt r2, [r0]
+ mov r0, #0
+ mov pc, lr
+
+ .global __put_user_8
+__put_user_8:
+5: strt r2, [r0], #4
+6: strt r3, [r0]
+ mov r0, #0
+ mov pc, lr
+
+__put_user_bad:
+ mov r0, #-EFAULT
+ mov pc, lr
+
+.section __ex_table, "a"
+ .long 1b, __put_user_bad
+ .long 2b, __put_user_bad
+ .long 3b, __put_user_bad
+ .long 4b, __put_user_bad
+ .long 5b, __put_user_bad
+ .long 6b, __put_user_bad
+.previous
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