From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH v2 04/20] unify generic instances of csum_partial_copy_nocheck() Date: Fri, 24 Jul 2020 07:41:17 +0100 Message-ID: <20200724064117.GA10522@infradead.org> References: <20200724012512.GK2786714@ZenIV.linux.org.uk> <20200724012546.302155-1-viro@ZenIV.linux.org.uk> <20200724012546.302155-4-viro@ZenIV.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726567AbgGXGlU (ORCPT ); Fri, 24 Jul 2020 02:41:20 -0400 Content-Disposition: inline In-Reply-To: <20200724012546.302155-4-viro@ZenIV.linux.org.uk> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Al Viro Cc: Linus Torvalds , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org On Fri, Jul 24, 2020 at 02:25:30AM +0100, Al Viro wrote: > From: 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. 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