path: root/lib/checksum.c
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2020-08-20unify generic instances of csum_partial_copy_nocheck()Al Viro
quite a few architectures have the same csum_partial_copy_nocheck() - simply memcpy() the data and then return the csum of the copy. hexagon, parisc, ia64, s390, um: explicitly spelled out that way. arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32, nios2, openrisc, riscv, unicore32: end up picking the same thing spelled out in lib/checksum.h (with varying amounts of perversions along the way). everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc, sh, sparc, x86, xtensa) have non-generic variants. For all except c6x the declaration is in their asm/checksum.h. c6x uses the wrapper from asm-generic/checksum.h that would normally lead to the lib/checksum.h instance, but in case of c6x we end up using an asm function from arch/c6x instead. Screw that mess - have architectures with private instances define _HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY *not* defined. Signed-off-by: Al Viro <>
2020-07-20arch, net: remove the last csum_partial_copy() leftoversChristoph Hellwig
Most of the tree only uses and implements csum_partial_copy_nocheck, but the c6x and lib/checksum.c implement a csum_partial_copy that isn't used anywere except to define csum_partial_copy. Get rid of this pointless alias. Signed-off-by: Christoph Hellwig <> Signed-off-by: David S. Miller <>
2020-05-29take the dummy csum_and_copy_from_user() into net/checksum.hAl Viro
now that can be done conveniently - all non-trivial cases have _HAVE_ARCH_COPY_AND_CSUM_FROM_USER defined, so the fallback in net/checksum.h is used only for dummy (copy_from_user, then csum_partial) implementation. Allowing us to get rid of all dummy instances, both of csum_and_copy_from_user() and csum_partial_copy_from_user(). Signed-off-by: Al Viro <>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <> Reviewed-by: Allison Randal <> Cc: Link: Signed-off-by: Greg Kroah-Hartman <>
2016-03-13ipv4: Update parameters for csum_tcpudp_magic to their original typesAlexander Duyck
This patch updates all instances of csum_tcpudp_magic and csum_tcpudp_nofold to reflect the types that are usually used as the source inputs. For example the protocol field is populated based on nexthdr which is actually an unsigned 8 bit value. The length is usually populated based on skb->len which is an unsigned integer. This addresses an issue in which the IPv6 function csum_ipv6_magic was generating a checksum using the full 32b of skb->len while csum_tcpudp_magic was only using the lower 16 bits. As a result we could run into issues when attempting to adjust the checksum as there was no protocol agnostic way to update it. With this change the value is still truncated as many architectures use "(len + proto) << 8", however this truncation only occurs for values greater than 16776960 in length and as such is unlikely to occur as we stop the inner headers at ~64K in size. I did have to make a few minor changes in the arm, mn10300, nios2, and score versions of the function in order to support these changes as they were either using things such as an OR to combine the protocol and length, or were using ntohs to convert the length which would have truncated the value. I also updated a few spots in terms of whitespace and type differences for the addresses. Most of this was just to make sure all of the definitions were in sync going forward. Signed-off-by: Alexander Duyck <> Signed-off-by: David S. Miller <>
2015-01-29lib/checksum.c: fix build for generic csum_tcpudp_nofoldkarl beldan
Fixed commit added from64to32 under _#ifndef do_csum_ but used it under _#ifndef csum_tcpudp_nofold_, breaking some builds (Fengguang's robot reported TILEGX's). Move from64to32 under the latter. Fixes: 150ae0e94634 ("lib/checksum.c: fix carry in csum_tcpudp_nofold") Reported-by: kbuild test robot <> Signed-off-by: Karl Beldan <> Cc: Eric Dumazet <> Cc: David S. Miller <> Signed-off-by: David S. Miller <>
2015-01-28lib/checksum.c: fix carry in csum_tcpudp_nofoldkarl beldan
The carry from the 64->32bits folding was dropped, e.g with: saddr=0xFFFFFFFF daddr=0xFF0000FF len=0xFFFF proto=0 sum=1, csum_tcpudp_nofold returned 0 instead of 1. Signed-off-by: Karl Beldan <> Cc: Al Viro <> Cc: Eric Dumazet <> Cc: Arnd Bergmann <> Cc: Mike Frysinger <> Cc: Cc: Cc: Signed-off-by: Eric Dumazet <> Signed-off-by: David S. Miller <>
2013-02-11asm-generic headers: Allow yet more arch overrides in checksum.hVineet Gupta
arches can have more efficient implementation of these routines Acked-by: Arnd Bergmann <> Signed-off-by: Vineet Gupta <>
2012-03-07lib: reduce the use of module.h wherever possiblePaul Gortmaker
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <>
2011-07-07lib/checksum.c: optimize do_csum a bitIan Abbott
Reduce the number of variables modified by the loop in do_csum() by 1, which seems like a good idea. On Nios II (a RISC CPU with 3-operand instruction set) it reduces the loop from 7 to 6 instructions, including the conditional branch. Signed-off-by: Ian Abbott <> Signed-off-by: David S. Miller <>
2009-11-03lib/checksum: fix one more thinkoArnd Bergmann
When do_csum gets unaligned data, we really need to treat the first byte as an even byte, not an odd byte, because we swap the two halves later. Found by Mike's checksum-selftest module. Reported-by: Mike Frysinger <> Signed-off-by: Arnd Bergmann <>
2009-11-03lib/checksum.c: make do_csum optionalArnd Bergmann
Mike Frysinger suggested that do_csum should be optional so that an architecture can use the generic checksum code but still provide an optimized fast-path for the most critical function. This can mean an implementation using inline assembly, or in case of Alpha one using 64-bit arithmetic in C. Cc: Mike Frysinger <> Signed-off-by: Arnd Bergmann <>
2009-11-03lib/checksum.c: use 32-bit arithmetic consistentlyArnd Bergmann
The use of 'unsigned long' variables in the 32-bit part of do_csum() is confusing at best, and potentially broken for long input on 64-bit machines. This changes the code to use 'unsigned int' instead, which makes the code behave in the same (correct) way on both 32 and 64 bit machines. Reported-by: Linus Torvalds <> Signed-off-by: Arnd Bergmann <>
2009-06-19lib/checksum.c: fix endianess bugArnd Bergmann
The new generic checksum code has a small dependency on endianess and worked only on big-endian systems. I could not find a nice efficient way to express this, so I added an #ifdef. Using 'result += le16_to_cpu(*buff);' would have worked as well, but would be slightly less efficient on big-endian systems and IMHO would not be clearer. Also fix a bug that prevents this from working on 64-bit machines. If you have a 64-bit CPU and want to use the generic checksum code, you should probably do some more optimizations anyway, but at least the code should not break. Reported-by: Mike Frysinger <> Signed-off-by: Arnd Bergmann <>
2009-06-11add generic lib/checksum.cArnd Bergmann
Add a generic (unoptimized) implementation of checksum.c in pure C for use by all architectures that cannot be bother with implementing their own version. Based on microblaze code by Michal Simek <> Cc: Michal Simek <> Signed-off-by: Remis Lima Baima <> Signed-off-by: Arnd Bergmann <>