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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 22:20:36 (GMT)
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 22:20:36 (GMT)
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-v850/checksum.h
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-v850/checksum.h')
-rw-r--r--include/asm-v850/checksum.h115
1 files changed, 115 insertions, 0 deletions
diff --git a/include/asm-v850/checksum.h b/include/asm-v850/checksum.h
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+++ b/include/asm-v850/checksum.h
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+/*
+ * include/asm-v850/checksum.h -- Checksum ops
+ *
+ * Copyright (C) 2001 NEC Corporation
+ * Copyright (C) 2001 Miles Bader <miles@gnu.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ * Written by Miles Bader <miles@gnu.org>
+ */
+
+#ifndef __V850_CHECKSUM_H__
+#define __V850_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
+ */
+extern unsigned int csum_partial (const unsigned char * buff, int len,
+ unsigned int 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
+ */
+extern unsigned csum_partial_copy (const char *src, char *dst, int len,
+ unsigned sum);
+
+
+/*
+ * the same as csum_partial_copy, but copies from user space.
+ *
+ * here even more important to align src and dst on a 32-bit (or even
+ * better 64-bit) boundary
+ */
+extern unsigned csum_partial_copy_from_user (const char *src, char *dst,
+ int len, unsigned sum,
+ int *csum_err);
+
+#define csum_partial_copy_nocheck(src, dst, len, sum) \
+ csum_partial_copy ((src), (dst), (len), (sum))
+
+unsigned short ip_fast_csum (unsigned char *iph, unsigned int ihl);
+
+/*
+ * Fold a partial checksum
+ */
+static inline unsigned int csum_fold (unsigned long sum)
+{
+ unsigned int result;
+ /*
+ %0 %1
+ hsw %1, %0 H L L H
+ add %1, %0 H L H+L+C H+L
+ */
+ asm ("hsw %1, %0; add %1, %0" : "=&r" (result) : "r" (sum));
+ return (~result) >> 16;
+}
+
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+static inline unsigned int
+csum_tcpudp_nofold (unsigned long saddr, unsigned long daddr,
+ unsigned short len,
+ unsigned short proto, unsigned int sum)
+{
+ int __carry;
+ __asm__ ("add %2, %0;"
+ "setf c, %1;"
+ "add %1, %0;"
+ "add %3, %0;"
+ "setf c, %1;"
+ "add %1, %0;"
+ "add %4, %0;"
+ "setf c, %1;"
+ "add %1, %0"
+ : "=&r" (sum), "=&r" (__carry)
+ : "r" (daddr), "r" (saddr),
+ "r" (ntohs (len) + (proto << 8)),
+ "0" (sum));
+ return sum;
+}
+
+static inline unsigned short int
+csum_tcpudp_magic (unsigned long saddr, unsigned long daddr,
+ unsigned short len,
+ unsigned short proto, unsigned int 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
+ */
+extern unsigned short ip_compute_csum (const unsigned char * buff, int len);
+
+
+#endif /* __V850_CHECKSUM_H__ */