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-rw-r--r--arch/cris/include/asm/checksum.h83
1 files changed, 83 insertions, 0 deletions
diff --git a/arch/cris/include/asm/checksum.h b/arch/cris/include/asm/checksum.h
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+++ b/arch/cris/include/asm/checksum.h
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+/* TODO: csum_tcpudp_magic could be speeded up, and csum_fold as well */
+
+#ifndef _CRIS_CHECKSUM_H
+#define _CRIS_CHECKSUM_H
+
+#include <arch/checksum.h>
+
+/*
+ * computes the checksum of a memory block at buff, length len,
+ * and adds in "sum" (32-bit)
+ *
+ * returns a 32-bit number suitable for feeding into itself
+ * or csum_tcpudp_magic
+ *
+ * this function must be called with even lengths, except
+ * for the last fragment, which may be odd
+ *
+ * it's best to have buff aligned on a 32-bit boundary
+ */
+__wsum csum_partial(const void *buff, int len, __wsum sum);
+
+/*
+ * the same as csum_partial, but copies from src while it
+ * checksums
+ *
+ * here even more important to align src and dst on a 32-bit (or even
+ * better 64-bit) boundary
+ */
+
+__wsum csum_partial_copy_nocheck(const void *src, void *dst,
+ int len, __wsum sum);
+
+/*
+ * Fold a partial checksum into a word
+ */
+
+static inline __sum16 csum_fold(__wsum csum)
+{
+ u32 sum = (__force u32)csum;
+ sum = (sum & 0xffff) + (sum >> 16); /* add in end-around carry */
+ sum = (sum & 0xffff) + (sum >> 16); /* add in end-around carry */
+ return (__force __sum16)~sum;
+}
+
+extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
+ int len, __wsum sum,
+ int *errptr);
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ *
+ */
+
+static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+ return csum_fold(csum_partial(iph, ihl * 4, 0));
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+
+static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
+ unsigned short len,
+ unsigned short proto,
+ __wsum sum)
+{
+ return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
+}
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+
+static inline __sum16 ip_compute_csum(const void *buff, int len)
+{
+ return csum_fold (csum_partial(buff, len, 0));
+}
+
+#endif