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+/*
+ * linux/arch/arm/lib/copy_from_user.S
+ *
+ * Author: Nicolas Pitre
+ * Created: Sep 29, 2005
+ * Copyright: MontaVista Software, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Prototype:
+ *
+ * size_t __arch_copy_from_user(void *to, const void *from, size_t n)
+ *
+ * Purpose:
+ *
+ * copy a block to kernel memory from user memory
+ *
+ * Params:
+ *
+ * to = kernel memory
+ * from = user memory
+ * n = number of bytes to copy
+ *
+ * Return value:
+ *
+ * Number of bytes NOT copied.
+ */
+
+ .macro ldr1w ptr reg abort
+100: ldrt \reg, [\ptr], #4
+ .section __ex_table, "a"
+ .long 100b, \abort
+ .previous
+ .endm
+
+ .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
+ ldr1w \ptr, \reg1, \abort
+ ldr1w \ptr, \reg2, \abort
+ ldr1w \ptr, \reg3, \abort
+ ldr1w \ptr, \reg4, \abort
+ .endm
+
+ .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ ldr4w \ptr, \reg1, \reg2, \reg3, \reg4, \abort
+ ldr4w \ptr, \reg5, \reg6, \reg7, \reg8, \abort
+ .endm
+
+ .macro ldr1b ptr reg cond=al abort
+100: ldr\cond\()bt \reg, [\ptr], #1
+ .section __ex_table, "a"
+ .long 100b, \abort
+ .previous
+ .endm
+
+ .macro str1w ptr reg abort
+ str \reg, [\ptr], #4
+ .endm
+
+ .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
+ .endm
+
+ .macro str1b ptr reg cond=al abort
+ str\cond\()b \reg, [\ptr], #1
+ .endm
+
+ .macro enter reg1 reg2
+ mov r3, #0
+ stmdb sp!, {r0, r2, r3, \reg1, \reg2}
+ .endm
+
+ .macro exit reg1 reg2
+ add sp, sp, #8
+ ldmfd sp!, {r0, \reg1, \reg2}
+ .endm
+
+ .text
+
+ENTRY(__arch_copy_from_user)
+
+#include "copy_template.S"
+
+ .section .fixup,"ax"
+ .align 0
+ copy_abort_preamble
+ ldmfd sp!, {r1, r2}
+ sub r3, r0, r1
+ rsb r1, r3, r2
+ str r1, [sp]
+ bl __memzero
+ ldr r0, [sp], #4
+ copy_abort_end
+ .previous
+