patch-2.4.13 linux/arch/arm/lib/getuser.S

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diff -u --recursive --new-file v2.4.12/linux/arch/arm/lib/getuser.S linux/arch/arm/lib/getuser.S
@@ -0,0 +1,96 @@
+/*
+ *  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
+ *		r1, r2 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>
+
+	.global	__get_user_1
+__get_user_1:
+	bic	r1, sp, #0x1f00
+	bic	r1, r1, #0x00ff
+	ldr	r1, [r1, #TSK_ADDR_LIMIT]
+	sub	r1, r1, #1
+	cmp	r0, r1
+1:	ldrlsbt	r1, [r0]
+	movls	r0, #0
+	movls	pc, lr
+	b	__get_user_bad
+
+	.global	__get_user_2
+__get_user_2:
+	bic	r2, sp, #0x1f00
+	bic	r2, r2, #0x00ff
+	ldr	r2, [r2, #TSK_ADDR_LIMIT]
+	sub	r2, r2, #2
+	cmp	r0, r2
+2:	ldrlsbt	r1, [r0], #1
+3:	ldrlsbt	r2, [r0]
+	orrls	r1, r1, r2, lsl #8
+	movls	r0, #0
+	movls	pc, lr
+	b	__get_user_bad
+
+	.global	__get_user_4
+__get_user_4:
+	bic	r1, sp, #0x1f00
+	bic	r1, r1, #0x00ff
+	ldr	r1, [r1, #TSK_ADDR_LIMIT]
+	sub	r1, r1, #4
+	cmp	r0, r1
+4:	ldrlst	r1, [r0]
+	movls	r0, #0
+	movls	pc, lr
+	b	__get_user_bad
+
+	.global	__get_user_8
+__get_user_8:
+	bic	r2, sp, #0x1f00
+	bic	r2, r2, #0x00ff
+	ldr	r2, [r2, #TSK_ADDR_LIMIT]
+	sub	r2, r2, #8
+	cmp	r0, r2
+5:	ldrlst	r1, [r0], #4
+6:	ldrlst	r2, [r0]
+	movls	r0, #0
+	movls	pc, lr
+
+	/* fall through */
+
+__get_user_bad:
+	mov	r2, #0
+	mov	r1, #0
+	mov	r0, #-14
+	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
+	.long	6b, __get_user_bad
+.previous

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