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authorGreg Ungerer <gerg@uclinux.org>2011-03-22 13:39:27 +1000
committerGreg Ungerer <gerg@uclinux.org>2011-03-25 14:05:13 +1000
commit66d857b08b8c3ed5c72c361f863cce77d2a978d7 (patch)
tree47222d86f4d78dc0da31baf64188bd2e4b38ac1e /arch/m68k/lib/checksum_no.c
parentd39dd11c3e6a7af5c20bfac40594db36cf270f42 (diff)
m68k: merge m68k and m68knommu arch directories
There is a lot of common code that could be shared between the m68k and m68knommu arch branches. It makes sense to merge the two branches into a single directory structure so that we can more easily share that common code. This is a brute force merge, based on a script from Stephen King <sfking@fdwdc.com>, which was originally written by Arnd Bergmann <arnd@arndb.de>. > The script was inspired by the script Sam Ravnborg used to merge the > includes from m68knommu. For those files common to both arches but > differing in content, the m68k version of the file is renamed to > <file>_mm.<ext> and the m68knommu version of the file is moved into the > corresponding m68k directory and renamed <file>_no.<ext> and a small > wrapper file <file>.<ext> is used to select between the two version. Files > that are common to both but don't differ are removed from the m68knommu > tree and files and directories that are unique to the m68knommu tree are > moved to the m68k tree. Finally, the arch/m68knommu tree is removed. > > To select between the the versions of the files, the wrapper uses > > #ifdef CONFIG_MMU > #include <file>_mm.<ext> > #else > #include <file>_no.<ext> > #endif On top of this file merge I have done a simplistic merge of m68k and m68knommu Kconfig, which primarily attempts to keep existing options and menus in place. Other than a handful of options being moved it produces identical .config outputs on m68k and m68knommu targets I tested it on. With this in place there is now quite a bit of scope for merge cleanups in future patches. Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Diffstat (limited to 'arch/m68k/lib/checksum_no.c')
-rw-r--r--arch/m68k/lib/checksum_no.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/arch/m68k/lib/checksum_no.c b/arch/m68k/lib/checksum_no.c
new file mode 100644
index 000000000000..eccf25d3d73e
--- /dev/null
+++ b/arch/m68k/lib/checksum_no.c
@@ -0,0 +1,153 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * IP/TCP/UDP checksumming routines
+ *
+ * Authors: Jorge Cwik, <jorge@laser.satlink.net>
+ * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
+ * Tom May, <ftom@netcom.com>
+ * Andreas Schwab, <schwab@issan.informatik.uni-dortmund.de>
+ * Lots of code moved from tcp.c and ip.c; see those files
+ * for more names.
+ *
+ * 03/02/96 Jes Sorensen, Andreas Schwab, Roman Hodek:
+ * Fixed some nasty bugs, causing some horrible crashes.
+ * A: At some points, the sum (%0) was used as
+ * length-counter instead of the length counter
+ * (%1). Thanks to Roman Hodek for pointing this out.
+ * B: GCC seems to mess up if one uses too many
+ * data-registers to hold input values and one tries to
+ * specify d0 and d1 as scratch registers. Letting gcc choose these
+ * registers itself solves the problem.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+/* Revised by Kenneth Albanowski for m68knommu. Basic problem: unaligned access kills, so most
+ of the assembly has to go. */
+
+#include <linux/module.h>
+#include <net/checksum.h>
+
+static inline unsigned short from32to16(unsigned long x)
+{
+ /* add up 16-bit and 16-bit for 16+c bit */
+ x = (x & 0xffff) + (x >> 16);
+ /* add up carry.. */
+ x = (x & 0xffff) + (x >> 16);
+ return x;
+}
+
+static unsigned long do_csum(const unsigned char * buff, int len)
+{
+ int odd, count;
+ unsigned long result = 0;
+
+ if (len <= 0)
+ goto out;
+ odd = 1 & (unsigned long) buff;
+ if (odd) {
+ result = *buff;
+ len--;
+ buff++;
+ }
+ count = len >> 1; /* nr of 16-bit words.. */
+ if (count) {
+ if (2 & (unsigned long) buff) {
+ result += *(unsigned short *) buff;
+ count--;
+ len -= 2;
+ buff += 2;
+ }
+ count >>= 1; /* nr of 32-bit words.. */
+ if (count) {
+ unsigned long carry = 0;
+ do {
+ unsigned long w = *(unsigned long *) buff;
+ count--;
+ buff += 4;
+ result += carry;
+ result += w;
+ carry = (w > result);
+ } while (count);
+ result += carry;
+ result = (result & 0xffff) + (result >> 16);
+ }
+ if (len & 2) {
+ result += *(unsigned short *) buff;
+ buff += 2;
+ }
+ }
+ if (len & 1)
+ result += (*buff << 8);
+ result = from32to16(result);
+ if (odd)
+ result = ((result >> 8) & 0xff) | ((result & 0xff) << 8);
+out:
+ return result;
+}
+
+#ifdef CONFIG_COLDFIRE
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ */
+__sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+ return (__force __sum16)~do_csum(iph,ihl*4);
+}
+#endif
+
+/*
+ * 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)
+{
+ unsigned int result = do_csum(buff, len);
+
+ /* add in old sum, and carry.. */
+ result += (__force u32)sum;
+ if ((__force u32)sum > result)
+ result += 1;
+ return (__force __wsum)result;
+}
+
+EXPORT_SYMBOL(csum_partial);
+
+/*
+ * copy from fs while checksumming, otherwise like csum_partial
+ */
+
+__wsum
+csum_partial_copy_from_user(const void __user *src, void *dst,
+ int len, __wsum sum, int *csum_err)
+{
+ if (csum_err) *csum_err = 0;
+ memcpy(dst, (__force const void *)src, len);
+ return csum_partial(dst, len, sum);
+}
+
+/*
+ * copy from ds while checksumming, otherwise like csum_partial
+ */
+
+__wsum
+csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+{
+ memcpy(dst, src, len);
+ return csum_partial(dst, len, sum);
+}