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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/ia64/lib/checksum.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/ia64/lib/checksum.c')
-rw-r--r--kernel/arch/ia64/lib/checksum.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/kernel/arch/ia64/lib/checksum.c b/kernel/arch/ia64/lib/checksum.c
new file mode 100644
index 000000000..9fc955026
--- /dev/null
+++ b/kernel/arch/ia64/lib/checksum.c
@@ -0,0 +1,101 @@
+/*
+ * Network checksum routines
+ *
+ * Copyright (C) 1999, 2003 Hewlett-Packard Co
+ * Stephane Eranian <eranian@hpl.hp.com>
+ *
+ * Most of the code coming from arch/alpha/lib/checksum.c
+ *
+ * This file contains network checksum routines that are better done
+ * in an architecture-specific manner due to speed..
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+
+#include <asm/byteorder.h>
+
+static inline unsigned short
+from64to16 (unsigned long x)
+{
+ /* add up 32-bit words for 33 bits */
+ x = (x & 0xffffffff) + (x >> 32);
+ /* add up 16-bit and 17-bit words for 17+c bits */
+ x = (x & 0xffff) + (x >> 16);
+ /* add up 16-bit and 2-bit for 16+c bit */
+ x = (x & 0xffff) + (x >> 16);
+ /* add up carry.. */
+ x = (x & 0xffff) + (x >> 16);
+ return x;
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented.
+ */
+__sum16
+csum_tcpudp_magic (__be32 saddr, __be32 daddr, unsigned short len,
+ unsigned short proto, __wsum sum)
+{
+ return (__force __sum16)~from64to16(
+ (__force u64)saddr + (__force u64)daddr +
+ (__force u64)sum + ((len + proto) << 8));
+}
+
+EXPORT_SYMBOL(csum_tcpudp_magic);
+
+__wsum
+csum_tcpudp_nofold (__be32 saddr, __be32 daddr, unsigned short len,
+ unsigned short proto, __wsum sum)
+{
+ unsigned long result;
+
+ result = (__force u64)saddr + (__force u64)daddr +
+ (__force u64)sum + ((len + proto) << 8);
+
+ /* Fold down to 32-bits so we don't lose in the typedef-less network stack. */
+ /* 64 to 33 */
+ result = (result & 0xffffffff) + (result >> 32);
+ /* 33 to 32 */
+ result = (result & 0xffffffff) + (result >> 32);
+ return (__force __wsum)result;
+}
+EXPORT_SYMBOL(csum_tcpudp_nofold);
+
+extern unsigned long do_csum (const unsigned char *, long);
+
+/*
+ * 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
+ */
+__wsum csum_partial(const void *buff, int len, __wsum sum)
+{
+ u64 result = do_csum(buff, len);
+
+ /* add in old sum, and carry.. */
+ result += (__force u32)sum;
+ /* 32+c bits -> 32 bits */
+ result = (result & 0xffffffff) + (result >> 32);
+ return (__force __wsum)result;
+}
+
+EXPORT_SYMBOL(csum_partial);
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+__sum16 ip_compute_csum (const void *buff, int len)
+{
+ return (__force __sum16)~do_csum(buff,len);
+}
+
+EXPORT_SYMBOL(ip_compute_csum);