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+/*
+ * linux/arch/arm26/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/asm_offsets.h>
+#include <asm/thread_info.h>
+#include <asm/errno.h>
+
+ .global __get_user_1
+__get_user_1:
+ bic r1, sp, #0x1f00
+ bic r1, r1, #0x00ff
+ str lr, [sp, #-4]!
+ ldr r1, [r1, #TI_ADDR_LIMIT]
+ sub r1, r1, #1
+ cmp r0, r1
+ bge __get_user_bad
+ cmp r0, #0x02000000
+1: ldrlsbt r1, [r0]
+ ldrgeb r1, [r0]
+ mov r0, #0
+ ldmfd sp!, {pc}^
+
+ .global __get_user_2
+__get_user_2:
+ bic r2, sp, #0x1f00
+ bic r2, r2, #0x00ff
+ str lr, [sp, #-4]!
+ ldr r2, [r2, #TI_ADDR_LIMIT]
+ sub r2, r2, #2
+ cmp r0, r2
+ bge __get_user_bad
+ cmp r0, #0x02000000
+2: ldrlsbt r1, [r0], #1
+3: ldrlsbt r2, [r0]
+ ldrgeb r1, [r0], #1
+ ldrgeb r2, [r0]
+ orr r1, r1, r2, lsl #8
+ mov r0, #0
+ ldmfd sp!, {pc}^
+
+ .global __get_user_4
+__get_user_4:
+ bic r1, sp, #0x1f00
+ bic r1, r1, #0x00ff
+ str lr, [sp, #-4]!
+ ldr r1, [r1, #TI_ADDR_LIMIT]
+ sub r1, r1, #4
+ cmp r0, r1
+ bge __get_user_bad
+ cmp r0, #0x02000000
+4: ldrlst r1, [r0]
+ ldrge r1, [r0]
+ mov r0, #0
+ ldmfd sp!, {pc}^
+
+ .global __get_user_8
+__get_user_8:
+ bic r2, sp, #0x1f00
+ bic r2, r2, #0x00ff
+ str lr, [sp, #-4]!
+ ldr r2, [r2, #TI_ADDR_LIMIT]
+ sub r2, r2, #8
+ cmp r0, r2
+ bge __get_user_bad_8
+ cmp r0, #0x02000000
+5: ldrlst r1, [r0], #4
+6: ldrlst r2, [r0]
+ ldrge r1, [r0], #4
+ ldrge r2, [r0]
+ mov r0, #0
+ ldmfd sp!, {pc}^
+
+__get_user_bad_8:
+ mov r2, #0
+__get_user_bad:
+ mov r1, #0
+ mov r0, #-EFAULT
+ ldmfd sp!, {pc}^
+
+.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