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-rw-r--r--arch/arm26/lib/uaccess-kernel.S173
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diff --git a/arch/arm26/lib/uaccess-kernel.S b/arch/arm26/lib/uaccess-kernel.S
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+/*
+ * linux/arch/arm26/lib/uaccess-kernel.S
+ *
+ * Copyright (C) 1998 Russell King
+ *
+ * Note! Some code fragments found in here have a special calling
+ * convention - they are not APCS compliant!
+ *
+ * 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>
+
+ .text
+
+//FIXME - surely this can be done in C not asm, removing the problem of keeping C and asm in sync? (this is a struct uaccess_t)
+
+ .globl uaccess_kernel
+uaccess_kernel:
+ .word uaccess_kernel_put_byte
+ .word uaccess_kernel_get_byte
+ .word uaccess_kernel_put_half
+ .word uaccess_kernel_get_half
+ .word uaccess_kernel_put_word
+ .word uaccess_kernel_get_word
+ .word uaccess_kernel_put_dword
+ .word uaccess_kernel_copy
+ .word uaccess_kernel_copy
+ .word uaccess_kernel_clear
+ .word uaccess_kernel_strncpy
+ .word uaccess_kernel_strnlen
+
+@ In : r0 = x, r1 = addr, r2 = error
+@ Out: r2 = error
+uaccess_kernel_put_byte:
+ stmfd sp!, {lr}
+ strb r0, [r1]
+ ldmfd sp!, {pc}^
+
+@ In : r0 = x, r1 = addr, r2 = error
+@ Out: r2 = error
+uaccess_kernel_put_half:
+ stmfd sp!, {lr}
+ strb r0, [r1]
+ mov r0, r0, lsr #8
+ strb r0, [r1, #1]
+ ldmfd sp!, {pc}^
+
+@ In : r0 = x, r1 = addr, r2 = error
+@ Out: r2 = error
+uaccess_kernel_put_word:
+ stmfd sp!, {lr}
+ str r0, [r1]
+ ldmfd sp!, {pc}^
+
+@ In : r0 = x, r1 = addr, r2 = error
+@ Out: r2 = error
+uaccess_kernel_put_dword:
+ stmfd sp!, {lr}
+ str r0, [r1], #4
+ str r0, [r1], #0
+ ldmfd sp!, {pc}^
+
+@ In : r0 = addr, r1 = error
+@ Out: r0 = x, r1 = error
+uaccess_kernel_get_byte:
+ stmfd sp!, {lr}
+ ldrb r0, [r0]
+ ldmfd sp!, {pc}^
+
+@ In : r0 = addr, r1 = error
+@ Out: r0 = x, r1 = error
+uaccess_kernel_get_half:
+ stmfd sp!, {lr}
+ ldr r0, [r0]
+ mov r0, r0, lsl #16
+ mov r0, r0, lsr #16
+ ldmfd sp!, {pc}^
+
+@ In : r0 = addr, r1 = error
+@ Out: r0 = x, r1 = error
+uaccess_kernel_get_word:
+ stmfd sp!, {lr}
+ ldr r0, [r0]
+ ldmfd sp!, {pc}^
+
+
+/* Prototype: int uaccess_kernel_copy(void *to, const char *from, size_t n)
+ * Purpose : copy a block to kernel memory from kernel memory
+ * Params : to - kernel memory
+ * : from - kernel memory
+ * : n - number of bytes to copy
+ * Returns : Number of bytes NOT copied.
+ */
+uaccess_kernel_copy:
+ stmfd sp!, {lr}
+ bl memcpy
+ mov r0, #0
+ ldmfd sp!, {pc}^
+
+/* Prototype: int uaccess_kernel_clear(void *addr, size_t sz)
+ * Purpose : clear some kernel memory
+ * Params : addr - kernel memory address to clear
+ * : sz - number of bytes to clear
+ * Returns : number of bytes NOT cleared
+ */
+uaccess_kernel_clear:
+ stmfd sp!, {lr}
+ mov r2, #0
+ cmp r1, #4
+ blt 2f
+ ands ip, r0, #3
+ beq 1f
+ cmp ip, #1
+ strb r2, [r0], #1
+ strleb r2, [r0], #1
+ strltb r2, [r0], #1
+ rsb ip, ip, #4
+ sub r1, r1, ip @ 7 6 5 4 3 2 1
+1: subs r1, r1, #8 @ -1 -2 -3 -4 -5 -6 -7
+ bmi 2f
+ str r2, [r0], #4
+ str r2, [r0], #4
+ b 1b
+2: adds r1, r1, #4 @ 3 2 1 0 -1 -2 -3
+ strpl r2, [r0], #4
+ tst r1, #2 @ 1x 1x 0x 0x 1x 1x 0x
+ strneb r2, [r0], #1
+ strneb r2, [r0], #1
+ tst r1, #1 @ x1 x0 x1 x0 x1 x0 x1
+ strneb r2, [r0], #1
+ mov r0, #0
+ ldmfd sp!, {pc}^
+
+/* Prototype: size_t uaccess_kernel_strncpy(char *dst, char *src, size_t len)
+ * Purpose : copy a string from kernel memory to kernel memory
+ * Params : dst - kernel memory destination
+ * : src - kernel memory source
+ * : len - maximum length of string
+ * Returns : number of characters copied
+ */
+uaccess_kernel_strncpy:
+ stmfd sp!, {lr}
+ mov ip, r2
+1: subs r2, r2, #1
+ bmi 2f
+ ldrb r3, [r1], #1
+ strb r3, [r0], #1
+ teq r3, #0
+ bne 1b
+2: subs r0, ip, r2
+ ldmfd sp!, {pc}^
+
+/* Prototype: int uaccess_kernel_strlen(char *str, long n)
+ * Purpose : get length of a string in kernel memory
+ * Params : str - address of string in kernel memory
+ * Returns : length of string *including terminator*,
+ * or zero on exception, or n + 1 if too long
+ */
+uaccess_kernel_strnlen:
+ stmfd sp!, {lr}
+ mov r2, r0
+1: ldrb r1, [r0], #1
+ teq r1, #0
+ beq 2f
+ subs r1, r1, #1
+ bne 1b
+ add r0, r0, #1
+2: sub r0, r0, r2
+ ldmfd sp!, {pc}^
+