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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-h8300/checksum.h
Linux-2.6.12-rc2v2.6.12-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-h8300/checksum.h')
-rw-r--r--include/asm-h8300/checksum.h105
1 files changed, 105 insertions, 0 deletions
diff --git a/include/asm-h8300/checksum.h b/include/asm-h8300/checksum.h
new file mode 100644
index 00000000000..3051931dd30
--- /dev/null
+++ b/include/asm-h8300/checksum.h
@@ -0,0 +1,105 @@
+#ifndef _H8300_CHECKSUM_H
+#define _H8300_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
+ */
+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
+ */
+
+unsigned int csum_partial_copy(const char *src, char *dst, int len, int 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 int csum_partial_copy_from_user(const char *src, char *dst,
+ int len, int 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 int sum)
+{
+ __asm__("mov.l %0,er0\n\t"
+ "add.w e0,r0\n\t"
+ "xor.w e0,e0\n\t"
+ "rotxl.w e0\n\t"
+ "add.w e0,r0\n\t"
+ "sub.w e0,e0\n\t"
+ "mov.l er0,%0"
+ : "=r"(sum)
+ : "0"(sum)
+ : "er0");
+ return ~sum;
+}
+
+
+/*
+ * 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)
+{
+ __asm__ ("sub.l er0,er0\n\t"
+ "add.l %2,%0\n\t"
+ "addx #0,r0l\n\t"
+ "add.l %3,%0\n\t"
+ "addx #0,r0l\n\t"
+ "add.l %4,%0\n\t"
+ "addx #0,r0l\n\t"
+ "add.l er0,%0\n\t"
+ "bcc 1f\n\t"
+ "inc.l #1,%0\n"
+ "1:"
+ : "=&r" (sum)
+ : "0" (sum), "r" (daddr), "r" (saddr), "r" (len + proto)
+ :"er0");
+ 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 /* _H8300_CHECKSUM_H */