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-rw-r--r--arch/mn10300/lib/checksum.c99
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
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+++ b/arch/mn10300/lib/checksum.c
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+/* 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);