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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/m68k/lib/checksum.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 |
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 'arch/m68k/lib/checksum.c')
-rw-r--r-- | arch/m68k/lib/checksum.c | 422 |
1 files changed, 422 insertions, 0 deletions
diff --git a/arch/m68k/lib/checksum.c b/arch/m68k/lib/checksum.c new file mode 100644 index 000000000000..4a5c5445c610 --- /dev/null +++ b/arch/m68k/lib/checksum.c @@ -0,0 +1,422 @@ +/* + * 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. + * + * 1998/8/31 Andreas Schwab: + * Zero out rest of buffer on exception in + * csum_partial_copy_from_user. + */ + +#include <linux/module.h> +#include <net/checksum.h> + +/* + * computes a partial checksum, e.g. for TCP/UDP fragments + */ + +unsigned int +csum_partial (const unsigned char *buff, int len, unsigned int sum) +{ + unsigned long tmp1, tmp2; + /* + * Experiments with ethernet and slip connections show that buff + * is aligned on either a 2-byte or 4-byte boundary. + */ + __asm__("movel %2,%3\n\t" + "btst #1,%3\n\t" /* Check alignment */ + "jeq 2f\n\t" + "subql #2,%1\n\t" /* buff%4==2: treat first word */ + "jgt 1f\n\t" + "addql #2,%1\n\t" /* len was == 2, treat only rest */ + "jra 4f\n" + "1:\t" + "addw %2@+,%0\n\t" /* add first word to sum */ + "clrl %3\n\t" + "addxl %3,%0\n" /* add X bit */ + "2:\t" + /* unrolled loop for the main part: do 8 longs at once */ + "movel %1,%3\n\t" /* save len in tmp1 */ + "lsrl #5,%1\n\t" /* len/32 */ + "jeq 2f\n\t" /* not enough... */ + "subql #1,%1\n" + "1:\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "dbra %1,1b\n\t" + "clrl %4\n\t" + "addxl %4,%0\n\t" /* add X bit */ + "clrw %1\n\t" + "subql #1,%1\n\t" + "jcc 1b\n" + "2:\t" + "movel %3,%1\n\t" /* restore len from tmp1 */ + "andw #0x1c,%3\n\t" /* number of rest longs */ + "jeq 4f\n\t" + "lsrw #2,%3\n\t" + "subqw #1,%3\n" + "3:\t" + /* loop for rest longs */ + "movel %2@+,%4\n\t" + "addxl %4,%0\n\t" + "dbra %3,3b\n\t" + "clrl %4\n\t" + "addxl %4,%0\n" /* add X bit */ + "4:\t" + /* now check for rest bytes that do not fit into longs */ + "andw #3,%1\n\t" + "jeq 7f\n\t" + "clrl %4\n\t" /* clear tmp2 for rest bytes */ + "subqw #2,%1\n\t" + "jlt 5f\n\t" + "movew %2@+,%4\n\t" /* have rest >= 2: get word */ + "swap %4\n\t" /* into bits 16..31 */ + "tstw %1\n\t" /* another byte? */ + "jeq 6f\n" + "5:\t" + "moveb %2@,%4\n\t" /* have odd rest: get byte */ + "lslw #8,%4\n\t" /* into bits 8..15; 16..31 untouched */ + "6:\t" + "addl %4,%0\n\t" /* now add rest long to sum */ + "clrl %4\n\t" + "addxl %4,%0\n" /* add X bit */ + "7:\t" + : "=d" (sum), "=d" (len), "=a" (buff), + "=&d" (tmp1), "=&d" (tmp2) + : "0" (sum), "1" (len), "2" (buff) + ); + return(sum); +} + +EXPORT_SYMBOL(csum_partial); + + +/* + * copy from user space while checksumming, with exception handling. + */ + +unsigned int +csum_partial_copy_from_user(const unsigned char *src, unsigned char *dst, + int len, int sum, int *csum_err) +{ + /* + * GCC doesn't like more than 10 operands for the asm + * statements so we have to use tmp2 for the error + * code. + */ + unsigned long tmp1, tmp2; + + __asm__("movel %2,%4\n\t" + "btst #1,%4\n\t" /* Check alignment */ + "jeq 2f\n\t" + "subql #2,%1\n\t" /* buff%4==2: treat first word */ + "jgt 1f\n\t" + "addql #2,%1\n\t" /* len was == 2, treat only rest */ + "jra 4f\n" + "1:\n" + "10:\t" + "movesw %2@+,%4\n\t" /* add first word to sum */ + "addw %4,%0\n\t" + "movew %4,%3@+\n\t" + "clrl %4\n\t" + "addxl %4,%0\n" /* add X bit */ + "2:\t" + /* unrolled loop for the main part: do 8 longs at once */ + "movel %1,%4\n\t" /* save len in tmp1 */ + "lsrl #5,%1\n\t" /* len/32 */ + "jeq 2f\n\t" /* not enough... */ + "subql #1,%1\n" + "1:\n" + "11:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "12:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "13:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "14:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "15:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "16:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "17:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "18:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "dbra %1,1b\n\t" + "clrl %5\n\t" + "addxl %5,%0\n\t" /* add X bit */ + "clrw %1\n\t" + "subql #1,%1\n\t" + "jcc 1b\n" + "2:\t" + "movel %4,%1\n\t" /* restore len from tmp1 */ + "andw #0x1c,%4\n\t" /* number of rest longs */ + "jeq 4f\n\t" + "lsrw #2,%4\n\t" + "subqw #1,%4\n" + "3:\n" + /* loop for rest longs */ + "19:\t" + "movesl %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "dbra %4,3b\n\t" + "clrl %5\n\t" + "addxl %5,%0\n" /* add X bit */ + "4:\t" + /* now check for rest bytes that do not fit into longs */ + "andw #3,%1\n\t" + "jeq 7f\n\t" + "clrl %5\n\t" /* clear tmp2 for rest bytes */ + "subqw #2,%1\n\t" + "jlt 5f\n\t" + "20:\t" + "movesw %2@+,%5\n\t" /* have rest >= 2: get word */ + "movew %5,%3@+\n\t" + "swap %5\n\t" /* into bits 16..31 */ + "tstw %1\n\t" /* another byte? */ + "jeq 6f\n" + "5:\n" + "21:\t" + "movesb %2@,%5\n\t" /* have odd rest: get byte */ + "moveb %5,%3@+\n\t" + "lslw #8,%5\n\t" /* into bits 8..15; 16..31 untouched */ + "6:\t" + "addl %5,%0\n\t" /* now add rest long to sum */ + "clrl %5\n\t" + "addxl %5,%0\n\t" /* add X bit */ + "7:\t" + "clrl %5\n" /* no error - clear return value */ + "8:\n" + ".section .fixup,\"ax\"\n" + ".even\n" + /* If any exception occurs zero out the rest. + Similarities with the code above are intentional :-) */ + "90:\t" + "clrw %3@+\n\t" + "movel %1,%4\n\t" + "lsrl #5,%1\n\t" + "jeq 1f\n\t" + "subql #1,%1\n" + "91:\t" + "clrl %3@+\n" + "92:\t" + "clrl %3@+\n" + "93:\t" + "clrl %3@+\n" + "94:\t" + "clrl %3@+\n" + "95:\t" + "clrl %3@+\n" + "96:\t" + "clrl %3@+\n" + "97:\t" + "clrl %3@+\n" + "98:\t" + "clrl %3@+\n\t" + "dbra %1,91b\n\t" + "clrw %1\n\t" + "subql #1,%1\n\t" + "jcc 91b\n" + "1:\t" + "movel %4,%1\n\t" + "andw #0x1c,%4\n\t" + "jeq 1f\n\t" + "lsrw #2,%4\n\t" + "subqw #1,%4\n" + "99:\t" + "clrl %3@+\n\t" + "dbra %4,99b\n\t" + "1:\t" + "andw #3,%1\n\t" + "jeq 9f\n" + "100:\t" + "clrw %3@+\n\t" + "tstw %1\n\t" + "jeq 9f\n" + "101:\t" + "clrb %3@+\n" + "9:\t" +#define STR(X) STR1(X) +#define STR1(X) #X + "moveq #-" STR(EFAULT) ",%5\n\t" + "jra 8b\n" + ".previous\n" + ".section __ex_table,\"a\"\n" + ".long 10b,90b\n" + ".long 11b,91b\n" + ".long 12b,92b\n" + ".long 13b,93b\n" + ".long 14b,94b\n" + ".long 15b,95b\n" + ".long 16b,96b\n" + ".long 17b,97b\n" + ".long 18b,98b\n" + ".long 19b,99b\n" + ".long 20b,100b\n" + ".long 21b,101b\n" + ".previous" + : "=d" (sum), "=d" (len), "=a" (src), "=a" (dst), + "=&d" (tmp1), "=d" (tmp2) + : "0" (sum), "1" (len), "2" (src), "3" (dst) + ); + + *csum_err = tmp2; + + return(sum); +} + +/* + * copy from kernel space while checksumming, otherwise like csum_partial + */ + +unsigned int +csum_partial_copy_nocheck(const unsigned char *src, unsigned char *dst, int len, int sum) +{ + unsigned long tmp1, tmp2; + __asm__("movel %2,%4\n\t" + "btst #1,%4\n\t" /* Check alignment */ + "jeq 2f\n\t" + "subql #2,%1\n\t" /* buff%4==2: treat first word */ + "jgt 1f\n\t" + "addql #2,%1\n\t" /* len was == 2, treat only rest */ + "jra 4f\n" + "1:\t" + "movew %2@+,%4\n\t" /* add first word to sum */ + "addw %4,%0\n\t" + "movew %4,%3@+\n\t" + "clrl %4\n\t" + "addxl %4,%0\n" /* add X bit */ + "2:\t" + /* unrolled loop for the main part: do 8 longs at once */ + "movel %1,%4\n\t" /* save len in tmp1 */ + "lsrl #5,%1\n\t" /* len/32 */ + "jeq 2f\n\t" /* not enough... */ + "subql #1,%1\n" + "1:\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "dbra %1,1b\n\t" + "clrl %5\n\t" + "addxl %5,%0\n\t" /* add X bit */ + "clrw %1\n\t" + "subql #1,%1\n\t" + "jcc 1b\n" + "2:\t" + "movel %4,%1\n\t" /* restore len from tmp1 */ + "andw #0x1c,%4\n\t" /* number of rest longs */ + "jeq 4f\n\t" + "lsrw #2,%4\n\t" + "subqw #1,%4\n" + "3:\t" + /* loop for rest longs */ + "movel %2@+,%5\n\t" + "addxl %5,%0\n\t" + "movel %5,%3@+\n\t" + "dbra %4,3b\n\t" + "clrl %5\n\t" + "addxl %5,%0\n" /* add X bit */ + "4:\t" + /* now check for rest bytes that do not fit into longs */ + "andw #3,%1\n\t" + "jeq 7f\n\t" + "clrl %5\n\t" /* clear tmp2 for rest bytes */ + "subqw #2,%1\n\t" + "jlt 5f\n\t" + "movew %2@+,%5\n\t" /* have rest >= 2: get word */ + "movew %5,%3@+\n\t" + "swap %5\n\t" /* into bits 16..31 */ + "tstw %1\n\t" /* another byte? */ + "jeq 6f\n" + "5:\t" + "moveb %2@,%5\n\t" /* have odd rest: get byte */ + "moveb %5,%3@+\n\t" + "lslw #8,%5\n" /* into bits 8..15; 16..31 untouched */ + "6:\t" + "addl %5,%0\n\t" /* now add rest long to sum */ + "clrl %5\n\t" + "addxl %5,%0\n" /* add X bit */ + "7:\t" + : "=d" (sum), "=d" (len), "=a" (src), "=a" (dst), + "=&d" (tmp1), "=&d" (tmp2) + : "0" (sum), "1" (len), "2" (src), "3" (dst) + ); + return(sum); +} |