1 files changed, 99 insertions, 0 deletions

diff --git a/arch/mn10300/lib/checksum.c b/arch/mn10300/lib/checksum.c
new file mode 100644
index 000000000000..274f29ec33c1
--- /dev/null
+++ b/arch/mn10300/lib/checksum.c
@@ -0,0 +1,99 @@
+/* MN10300 Optimised checksumming wrappers
+ *
+ * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <asm/byteorder.h>
+#include <asm/uaccess.h>
+#include <asm/checksum.h>
+#include "internal.h"
+
+static inline unsigned short from32to16(__wsum sum)
+{
+        asm("   add     %1,%0           \n"
+            "   addc    0xffff,%0       \n"
+            : "=r" (sum)
+            : "r" (sum << 16), "0" (sum & 0xffff0000)
+            );
+        return sum >> 16;
+}
+
+__sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+        return ~do_csum(iph, ihl * 4);
+}
+EXPORT_SYMBOL(ip_fast_csum);
+
+__wsum csum_partial(const void *buff, int len, __wsum sum)
+{
+        __wsum result;
+
+        result = do_csum(buff, len);
+        result += sum;
+        if (sum > result)
+                result++;
+        return result;
+}
+EXPORT_SYMBOL(csum_partial);
+
+__sum16 ip_compute_csum(const void *buff, int len)
+{
+        return ~from32to16(do_csum(buff, len));
+}
+EXPORT_SYMBOL(ip_compute_csum);
+
+__wsum csum_partial_copy(const void *src, void *dst, int len, __wsum sum)
+{
+        copy_from_user(dst, src, len);
+        return csum_partial(dst, len, sum);
+}
+EXPORT_SYMBOL(csum_partial_copy);
+
+__wsum csum_partial_copy_nocheck(const void *src, void *dst,
+                                 int len, __wsum sum)
+{
+        sum = csum_partial(src, len, sum);
+        memcpy(dst, src, len);
+        return sum;
+}
+EXPORT_SYMBOL(csum_partial_copy_nocheck);
+
+__wsum csum_partial_copy_from_user(const void *src, void *dst,
+                                   int len, __wsum sum,
+                                   int *err_ptr)
+{
+        int missing;
+
+        missing = copy_from_user(dst, src, len);
+        if (missing) {
+                memset(dst + len - missing, 0, missing);
+                *err_ptr = -EFAULT;
+        }
+
+        return csum_partial(dst, len, sum);
+}
+EXPORT_SYMBOL(csum_partial_copy_from_user);
+
+__wsum csum_and_copy_to_user(const void *src, void *dst,
+                             int len, __wsum sum,
+                             int *err_ptr)
+{
+        int missing;
+
+        missing = copy_to_user(dst, src, len);
+        if (missing) {
+                memset(dst + len - missing, 0, missing);
+                *err_ptr = -EFAULT;
+        }
+
+        return csum_partial(src, len, sum);
+}
+EXPORT_SYMBOL(csum_and_copy_to_user);