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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-m32r/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-m32r/checksum.h')
-rw-r--r--include/asm-m32r/checksum.h208
1 files changed, 208 insertions, 0 deletions
diff --git a/include/asm-m32r/checksum.h b/include/asm-m32r/checksum.h
new file mode 100644
index 00000000000..99f37dbf255
--- /dev/null
+++ b/include/asm-m32r/checksum.h
@@ -0,0 +1,208 @@
+#ifdef __KERNEL__
+#ifndef _ASM_M32R_CHECKSUM_H
+#define _ASM_M32R_CHECKSUM_H
+
+/*
+ * include/asm-m32r/checksum.h
+ *
+ * IP/TCP/UDP checksum routines
+ *
+ * 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.
+ *
+ * Some code taken from mips and parisc architecture.
+ *
+ * Copyright (C) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata
+ * Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
+ */
+
+#include <linux/in6.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
+ */
+asmlinkage 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 int csum_partial_copy_nocheck(const unsigned char *src,
+ unsigned char *dst,
+ int len, unsigned int sum);
+
+/*
+ * This is a new version of the above that records errors it finds in *errp,
+ * but continues and zeros thre rest of the buffer.
+ */
+extern unsigned int csum_partial_copy_from_user(const unsigned char __user *src,
+ unsigned char *dst,
+ int len, unsigned int sum,
+ int *err_ptr);
+
+/*
+ * Fold a partial checksum
+ */
+
+static inline unsigned int csum_fold(unsigned int sum)
+{
+ unsigned long tmpreg;
+ __asm__(
+ " sll3 %1, %0, #16 \n"
+ " cmp %0, %0 \n"
+ " addx %0, %1 \n"
+ " ldi %1, #0 \n"
+ " srli %0, #16 \n"
+ " addx %0, %1 \n"
+ " xor3 %0, %0, #0x0000ffff \n"
+ : "=r" (sum), "=&r" (tmpreg)
+ : "0" (sum)
+ : "cbit"
+ );
+ return sum;
+}
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ */
+static inline unsigned short ip_fast_csum(unsigned char * iph,
+ unsigned int ihl) {
+ unsigned long sum, tmpreg0, tmpreg1;
+
+ __asm__ __volatile__(
+ " ld %0, @%1+ \n"
+ " addi %2, #-4 \n"
+ "# bgez %2, 2f \n"
+ " cmp %0, %0 \n"
+ " ld %3, @%1+ \n"
+ " ld %4, @%1+ \n"
+ " addx %0, %3 \n"
+ " ld %3, @%1+ \n"
+ " addx %0, %4 \n"
+ " addx %0, %3 \n"
+ " .fillinsn\n"
+ "1: \n"
+ " ld %4, @%1+ \n"
+ " addi %2, #-1 \n"
+ " addx %0, %4 \n"
+ " bgtz %2, 1b \n"
+ "\n"
+ " ldi %3, #0 \n"
+ " addx %0, %3 \n"
+ " .fillinsn\n"
+ "2: \n"
+ /* Since the input registers which are loaded with iph and ipl
+ are modified, we must also specify them as outputs, or gcc
+ will assume they contain their original values. */
+ : "=&r" (sum), "=r" (iph), "=r" (ihl), "=&r" (tmpreg0), "=&r" (tmpreg1)
+ : "1" (iph), "2" (ihl)
+ : "cbit", "memory");
+
+ return csum_fold(sum);
+}
+
+static inline unsigned long csum_tcpudp_nofold(unsigned long saddr,
+ unsigned long daddr,
+ unsigned short len,
+ unsigned short proto,
+ unsigned int sum)
+{
+#if defined(__LITTLE_ENDIAN)
+ unsigned long len_proto = (ntohs(len)<<16)+proto*256;
+#else
+ unsigned long len_proto = (proto<<16)+len;
+#endif
+ unsigned long tmpreg;
+
+ __asm__(
+ " cmp %0, %0 \n"
+ " addx %0, %2 \n"
+ " addx %0, %3 \n"
+ " addx %0, %4 \n"
+ " ldi %1, #0 \n"
+ " addx %0, %1 \n"
+ : "=r" (sum), "=&r" (tmpreg)
+ : "r" (daddr), "r" (saddr), "r" (len_proto), "0" (sum)
+ : "cbit"
+ );
+
+ return sum;
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+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
+ */
+
+static inline unsigned short ip_compute_csum(unsigned char * buff, int len) {
+ return csum_fold (csum_partial(buff, len, 0));
+}
+
+#define _HAVE_ARCH_IPV6_CSUM
+static inline unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
+ struct in6_addr *daddr,
+ __u16 len,
+ unsigned short proto,
+ unsigned int sum)
+{
+ unsigned long tmpreg0, tmpreg1, tmpreg2, tmpreg3;
+ __asm__(
+ " ld %1, @(%5) \n"
+ " ld %2, @(4,%5) \n"
+ " ld %3, @(8,%5) \n"
+ " ld %4, @(12,%5) \n"
+ " add %0, %1 \n"
+ " addx %0, %2 \n"
+ " addx %0, %3 \n"
+ " addx %0, %4 \n"
+ " ld %1, @(%6) \n"
+ " ld %2, @(4,%6) \n"
+ " ld %3, @(8,%6) \n"
+ " ld %4, @(12,%6) \n"
+ " addx %0, %1 \n"
+ " addx %0, %2 \n"
+ " addx %0, %3 \n"
+ " addx %0, %4 \n"
+ " addx %0, %7 \n"
+ " addx %0, %8 \n"
+ " ldi %1, #0 \n"
+ " addx %0, %1 \n"
+ : "=&r" (sum), "=&r" (tmpreg0), "=&r" (tmpreg1),
+ "=&r" (tmpreg2), "=&r" (tmpreg3)
+ : "r" (saddr), "r" (daddr),
+ "r" (htonl((__u32) (len))), "r" (htonl(proto)), "0" (sum)
+ : "cbit"
+ );
+
+ return csum_fold(sum);
+}
+
+#endif /* _ASM_M32R_CHECKSUM_H */
+#endif /* __KERNEL__ */