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-rw-r--r--include/asm-mips/checksum.h253
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diff --git a/include/asm-mips/checksum.h b/include/asm-mips/checksum.h
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+++ b/include/asm-mips/checksum.h
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+/*
+ * 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.
+ *
+ * Copyright (C) 1995, 96, 97, 98, 99, 2001 by Ralf Baechle
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Copyright (C) 2001 Thiemo Seufer.
+ * Copyright (C) 2002 Maciej W. Rozycki
+ */
+#ifndef _ASM_CHECKSUM_H
+#define _ASM_CHECKSUM_H
+
+#include <linux/config.h>
+#include <linux/in6.h>
+
+#include <asm/uaccess.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);
+
+/*
+ * this is a new version of the above that records errors it finds in *errp,
+ * but continues and zeros the rest of the buffer.
+ */
+unsigned int csum_partial_copy_from_user(const unsigned char *src, unsigned char *dst, int len,
+ unsigned int sum, int *errp);
+
+/*
+ * Copy and checksum to user
+ */
+#define HAVE_CSUM_COPY_USER
+static inline unsigned int csum_and_copy_to_user (const unsigned char *src,
+ unsigned char __user *dst,
+ int len, int sum,
+ int *err_ptr)
+{
+ might_sleep();
+ sum = csum_partial(src, len, sum);
+
+ if (copy_to_user(dst, src, len)) {
+ *err_ptr = -EFAULT;
+ return -1;
+ }
+
+ return sum;
+}
+
+/*
+ * the same as csum_partial, but copies from user space (but on MIPS
+ * we have just one address space, so this is identical to the above)
+ */
+unsigned int csum_partial_copy_nocheck(const unsigned char *src, unsigned char *dst,
+ int len, unsigned int sum);
+
+/*
+ * Fold a partial checksum without adding pseudo headers
+ */
+static inline unsigned short int csum_fold(unsigned int sum)
+{
+ __asm__(
+ ".set\tnoat\t\t\t# csum_fold\n\t"
+ "sll\t$1,%0,16\n\t"
+ "addu\t%0,$1\n\t"
+ "sltu\t$1,%0,$1\n\t"
+ "srl\t%0,%0,16\n\t"
+ "addu\t%0,$1\n\t"
+ "xori\t%0,0xffff\n\t"
+ ".set\tat"
+ : "=r" (sum)
+ : "0" (sum));
+
+ return sum;
+}
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ *
+ * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by
+ * Arnt Gulbrandsen.
+ */
+static inline unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl)
+{
+ unsigned int *word = (unsigned int *) iph;
+ unsigned int *stop = word + ihl;
+ unsigned int csum;
+ int carry;
+
+ csum = word[0];
+ csum += word[1];
+ carry = (csum < word[1]);
+ csum += carry;
+
+ csum += word[2];
+ carry = (csum < word[2]);
+ csum += carry;
+
+ csum += word[3];
+ carry = (csum < word[3]);
+ csum += carry;
+
+ word += 4;
+ do {
+ csum += *word;
+ carry = (csum < *word);
+ csum += carry;
+ word++;
+ } while (word != stop);
+
+ return csum_fold(csum);
+}
+
+static inline unsigned int csum_tcpudp_nofold(unsigned long saddr,
+ unsigned long daddr, unsigned short len, unsigned short proto,
+ unsigned int sum)
+{
+ __asm__(
+ ".set\tnoat\t\t\t# csum_tcpudp_nofold\n\t"
+#ifdef CONFIG_MIPS32
+ "addu\t%0, %2\n\t"
+ "sltu\t$1, %0, %2\n\t"
+ "addu\t%0, $1\n\t"
+
+ "addu\t%0, %3\n\t"
+ "sltu\t$1, %0, %3\n\t"
+ "addu\t%0, $1\n\t"
+
+ "addu\t%0, %4\n\t"
+ "sltu\t$1, %0, %4\n\t"
+ "addu\t%0, $1\n\t"
+#endif
+#ifdef CONFIG_MIPS64
+ "daddu\t%0, %2\n\t"
+ "daddu\t%0, %3\n\t"
+ "daddu\t%0, %4\n\t"
+ "dsll32\t$1, %0, 0\n\t"
+ "daddu\t%0, $1\n\t"
+ "dsrl32\t%0, %0, 0\n\t"
+#endif
+ ".set\tat"
+ : "=r" (sum)
+ : "0" (daddr), "r"(saddr),
+#ifdef __MIPSEL__
+ "r" (((unsigned long)htons(len)<<16) + proto*256),
+#else
+ "r" (((unsigned long)(proto)<<16) + len),
+#endif
+ "r" (sum));
+
+ 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,
+ __u32 len,
+ unsigned short proto,
+ unsigned int sum)
+{
+ __asm__(
+ ".set\tpush\t\t\t# csum_ipv6_magic\n\t"
+ ".set\tnoreorder\n\t"
+ ".set\tnoat\n\t"
+ "addu\t%0, %5\t\t\t# proto (long in network byte order)\n\t"
+ "sltu\t$1, %0, %5\n\t"
+ "addu\t%0, $1\n\t"
+
+ "addu\t%0, %6\t\t\t# csum\n\t"
+ "sltu\t$1, %0, %6\n\t"
+ "lw\t%1, 0(%2)\t\t\t# four words source address\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "lw\t%1, 4(%2)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "lw\t%1, 8(%2)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "lw\t%1, 12(%2)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "lw\t%1, 0(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "lw\t%1, 4(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "lw\t%1, 8(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "lw\t%1, 12(%3)\n\t"
+ "addu\t%0, $1\n\t"
+ "addu\t%0, %1\n\t"
+ "sltu\t$1, %0, %1\n\t"
+
+ "addu\t%0, $1\t\t\t# Add final carry\n\t"
+ ".set\tpop"
+ : "=r" (sum), "=r" (proto)
+ : "r" (saddr), "r" (daddr),
+ "0" (htonl(len)), "1" (htonl(proto)), "r" (sum));
+
+ return csum_fold(sum);
+}
+
+#endif /* _ASM_CHECKSUM_H */
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