1 files changed, 111 insertions, 0 deletions
diff --git a/arch/arm/lib/copy_from_user.S b/arch/arm/lib/copy_from_user.S
new file mode 100644
index 000000000..f1e34f16c
--- /dev/null
+++ b/arch/arm/lib/copy_from_user.S
@@ -0,0 +1,111 @@
+/*
+ *  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>
+#include <asm/unwind.h>
+
+/*
+ * Prototype:
+ *
+ *	size_t arm_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.
+ */
+
+#ifndef CONFIG_THUMB2_KERNEL
+#define LDR1W_SHIFT	0
+#else
+#define LDR1W_SHIFT	1
+#endif
+#define STR1W_SHIFT	0
+
+	.macro ldr1w ptr reg abort
+	ldrusr	\reg, \ptr, 4, abort=\abort
+	.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
+	ldrusr	\reg, \ptr, 1, \cond, abort=\abort
+	.endm
+
+	.macro str1w ptr reg abort
+	W(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 usave reg1 reg2
+	UNWIND(	.save {r0, r2, r3, \reg1, \reg2}	)
+	.endm
+
+	.macro exit reg1 reg2
+	add	sp, sp, #8
+	ldmfd	sp!, {r0, \reg1, \reg2}
+	.endm
+
+	.text
+
+ENTRY(arm_copy_from_user)
+#ifdef CONFIG_CPU_SPECTRE
+	get_thread_info r3
+	ldr	r3, [r3, #TI_ADDR_LIMIT]
+	uaccess_mask_range_ptr r1, r2, r3, ip
+#endif
+
+#include "copy_template.S"
+
+ENDPROC(arm_copy_from_user)
+
+	.pushsection .text.fixup,"ax"
+	.align 0
+	copy_abort_preamble
+	ldmfd	sp!, {r1, r2, r3}
+	sub	r0, r0, r1
+	rsb	r0, r0, r2
+	copy_abort_end
+	.popsection
+