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authorPaul Mundt <lethal@linux-sh.org>2007-11-11 17:36:13 +0900
committerPaul Mundt <lethal@linux-sh.org>2008-01-28 13:18:45 +0900
commitfcfdd0f14f94d47f2f650a24cd111e11475ccada (patch)
tree3aa31620c31d66fb1ed72a93a3345e454f1df652 /include/asm-sh/checksum_32.h
parent63e2c803326babe74033b3cbe6e8c550037c554f (diff)
sh: Split out checksum.h in to _32 and _64 variants.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'include/asm-sh/checksum_32.h')
-rw-r--r--include/asm-sh/checksum_32.h215
1 files changed, 215 insertions, 0 deletions
diff --git a/include/asm-sh/checksum_32.h b/include/asm-sh/checksum_32.h
new file mode 100644
index 00000000000..4bc8357e889
--- /dev/null
+++ b/include/asm-sh/checksum_32.h
@@ -0,0 +1,215 @@
+#ifndef __ASM_SH_CHECKSUM_H
+#define __ASM_SH_CHECKSUM_H
+
+/*
+ * 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) 1999 by Kaz Kojima & Niibe Yutaka
+ */
+
+#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 __wsum csum_partial(const void *buff, int len, __wsum sum);
+
+/*
+ * the same as csum_partial, but copies from src while it
+ * checksums, and handles user-space pointer exceptions correctly, when needed.
+ *
+ * here even more important to align src and dst on a 32-bit (or even
+ * better 64-bit) boundary
+ */
+
+asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
+ int len, __wsum sum,
+ int *src_err_ptr, int *dst_err_ptr);
+
+/*
+ * Note: when you get a NULL pointer exception here this means someone
+ * passed in an incorrect kernel address to one of these functions.
+ *
+ * If you use these functions directly please don't forget the
+ * access_ok().
+ */
+static inline
+__wsum csum_partial_copy_nocheck(const void *src, void *dst,
+ int len, __wsum sum)
+{
+ return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
+}
+
+static inline
+__wsum csum_partial_copy_from_user(const void __user *src, void *dst,
+ int len, __wsum sum, int *err_ptr)
+{
+ return csum_partial_copy_generic((__force const void *)src, dst,
+ len, sum, err_ptr, NULL);
+}
+
+/*
+ * Fold a partial checksum
+ */
+
+static inline __sum16 csum_fold(__wsum sum)
+{
+ unsigned int __dummy;
+ __asm__("swap.w %0, %1\n\t"
+ "extu.w %0, %0\n\t"
+ "extu.w %1, %1\n\t"
+ "add %1, %0\n\t"
+ "swap.w %0, %1\n\t"
+ "add %1, %0\n\t"
+ "not %0, %0\n\t"
+ : "=r" (sum), "=&r" (__dummy)
+ : "0" (sum)
+ : "t");
+ return (__force __sum16)sum;
+}
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ *
+ * i386 version by Jorge Cwik <jorge@laser.satlink.net>, adapted
+ * for linux by * Arnt Gulbrandsen.
+ */
+static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+ unsigned int sum, __dummy0, __dummy1;
+
+ __asm__ __volatile__(
+ "mov.l @%1+, %0\n\t"
+ "mov.l @%1+, %3\n\t"
+ "add #-2, %2\n\t"
+ "clrt\n\t"
+ "1:\t"
+ "addc %3, %0\n\t"
+ "movt %4\n\t"
+ "mov.l @%1+, %3\n\t"
+ "dt %2\n\t"
+ "bf/s 1b\n\t"
+ " cmp/eq #1, %4\n\t"
+ "addc %3, %0\n\t"
+ "addc %2, %0" /* Here %2 is 0, add carry-bit */
+ /* Since the input registers which are loaded with iph and ihl
+ 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" (__dummy0), "=&z" (__dummy1)
+ : "1" (iph), "2" (ihl)
+ : "t");
+
+ return csum_fold(sum);
+}
+
+static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
+ unsigned short len,
+ unsigned short proto,
+ __wsum sum)
+{
+#ifdef __LITTLE_ENDIAN__
+ unsigned long len_proto = (proto + len) << 8;
+#else
+ unsigned long len_proto = proto + len;
+#endif
+ __asm__("clrt\n\t"
+ "addc %0, %1\n\t"
+ "addc %2, %1\n\t"
+ "addc %3, %1\n\t"
+ "movt %0\n\t"
+ "add %1, %0"
+ : "=r" (sum), "=r" (len_proto)
+ : "r" (daddr), "r" (saddr), "1" (len_proto), "0" (sum)
+ : "t");
+
+ return sum;
+}
+
+/*
+ * 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));
+}
+
+#define _HAVE_ARCH_IPV6_CSUM
+static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+ const struct in6_addr *daddr,
+ __u32 len, unsigned short proto,
+ __wsum sum)
+{
+ unsigned int __dummy;
+ __asm__("clrt\n\t"
+ "mov.l @(0,%2), %1\n\t"
+ "addc %1, %0\n\t"
+ "mov.l @(4,%2), %1\n\t"
+ "addc %1, %0\n\t"
+ "mov.l @(8,%2), %1\n\t"
+ "addc %1, %0\n\t"
+ "mov.l @(12,%2), %1\n\t"
+ "addc %1, %0\n\t"
+ "mov.l @(0,%3), %1\n\t"
+ "addc %1, %0\n\t"
+ "mov.l @(4,%3), %1\n\t"
+ "addc %1, %0\n\t"
+ "mov.l @(8,%3), %1\n\t"
+ "addc %1, %0\n\t"
+ "mov.l @(12,%3), %1\n\t"
+ "addc %1, %0\n\t"
+ "addc %4, %0\n\t"
+ "addc %5, %0\n\t"
+ "movt %1\n\t"
+ "add %1, %0\n"
+ : "=r" (sum), "=&r" (__dummy)
+ : "r" (saddr), "r" (daddr),
+ "r" (htonl(len)), "r" (htonl(proto)), "0" (sum)
+ : "t");
+
+ return csum_fold(sum);
+}
+
+/*
+ * Copy and checksum to user
+ */
+#define HAVE_CSUM_COPY_USER
+static inline __wsum csum_and_copy_to_user(const void *src,
+ void __user *dst,
+ int len, __wsum sum,
+ int *err_ptr)
+{
+ if (access_ok(VERIFY_WRITE, dst, len))
+ return csum_partial_copy_generic((__force const void *)src,
+ dst, len, sum, NULL, err_ptr);
+
+ if (len)
+ *err_ptr = -EFAULT;
+
+ return (__force __wsum)-1; /* invalid checksum */
+}
+#endif /* __ASM_SH_CHECKSUM_H */