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-rw-r--r--arch/sparc/lib/strncpy_from_user_32.S47
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/sparc/lib/strncpy_from_user_32.S b/arch/sparc/lib/strncpy_from_user_32.S
new file mode 100644
index 00000000000..d77198976a6
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+++ b/arch/sparc/lib/strncpy_from_user_32.S
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+/* strncpy_from_user.S: Sparc strncpy from userspace.
+ *
+ * Copyright(C) 1996 David S. Miller
+ */
+
+#include <asm/ptrace.h>
+#include <asm/errno.h>
+
+ .text
+ .align 4
+
+ /* Must return:
+ *
+ * -EFAULT for an exception
+ * count if we hit the buffer limit
+ * bytes copied if we hit a null byte
+ */
+
+ .globl __strncpy_from_user
+__strncpy_from_user:
+ /* %o0=dest, %o1=src, %o2=count */
+ mov %o2, %o3
+1:
+ subcc %o2, 1, %o2
+ bneg 2f
+ nop
+10:
+ ldub [%o1], %o4
+ add %o0, 1, %o0
+ cmp %o4, 0
+ add %o1, 1, %o1
+ bne 1b
+ stb %o4, [%o0 - 1]
+2:
+ add %o2, 1, %o0
+ retl
+ sub %o3, %o0, %o0
+
+ .section .fixup,#alloc,#execinstr
+ .align 4
+4:
+ retl
+ mov -EFAULT, %o0
+
+ .section __ex_table,#alloc
+ .align 4
+ .word 10b, 4b