On Fri, Jul 24, 2020 at 02:25:30AM +0100, Al Viro wrote: > From: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > > 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. net-next has a patch from me killing off csum_and_copy_from_user already: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=f1bfd71c8662f20d53e71ef4e18bfb0e5677c27f