This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / arch / avr32 / lib / strncpy_from_user.S

diff --git a/arch/avr32/lib/strncpy_from_user.S b/arch/avr32/lib/strncpy_from_user.S
new file mode 100644 (file)
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+++ b/arch/avr32/lib/strncpy_from_user.S
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+/*
+ * Copy to/from userspace with optional address space checking.
+ *
+ * Copyright 2004-2006 Atmel Corporation
+ *
+ * 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/errno.h>
+
+#include <asm/page.h>
+#include <asm/thread_info.h>
+#include <asm/asm.h>
+
+       /*
+        * long strncpy_from_user(char *dst, const char *src, long count)
+        *
+        * On success, returns the length of the string, not including
+        * the terminating NUL.
+        *
+        * If the string is longer than count, returns count
+        *
+        * If userspace access fails, returns -EFAULT
+        */
+       .text
+       .align  1
+       .global strncpy_from_user
+       .type   strncpy_from_user, "function"
+strncpy_from_user:
+       mov     r9, -EFAULT
+       branch_if_kernel r8, __strncpy_from_user
+       ret_if_privileged r8, r11, r10, r9
+
+       .global __strncpy_from_user
+       .type   __strncpy_from_user, "function"
+__strncpy_from_user:
+       cp.w    r10, 0
+       reteq   0
+
+       mov     r9, r10
+
+1:     ld.ub   r8, r11++
+       st.b    r12++, r8
+       cp.w    r8, 0
+       breq    2f
+       sub     r9, 1
+       brne    1b
+
+2:     sub     r10, r9
+       retal   r10
+
+       .section .fixup, "ax"
+       .align  1
+3:     mov     r12, -EFAULT
+       retal   r12
+
+       .section __ex_table, "a"
+       .align  2
+       .long   1b, 3b