From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A133C77B7E for ; Fri, 26 May 2023 00:50:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235394AbjEZAul (ORCPT ); Thu, 25 May 2023 20:50:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229878AbjEZAuk (ORCPT ); Thu, 25 May 2023 20:50:40 -0400 Received: from out-9.mta1.migadu.com (out-9.mta1.migadu.com [IPv6:2001:41d0:203:375::9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C02F194 for ; Thu, 25 May 2023 17:50:39 -0700 (PDT) Date: Thu, 25 May 2023 20:50:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1685062237; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=XccFcqhRV9oVZ2BhjoWlowoz0O43NBdleRYrqpo+tGk=; b=te1MA/PDmp4dIRH1TY49m1pWccvyo+kxGKHIAX3+k8t98qQbEiPCWJYi4Gkczlt1aIn7En cHq/akYRgnPKxFNi2vHECVpzXGpjZ3XraNt/Yalda8BuacVJcdSo4hYF5j3kzlTDgdIB0w GQUPt6jslW3+faac2EkPdAimK2RxUyY= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Kent Overstreet To: Dave Chinner Cc: linux-kernel@vger.kernel.org, axboe@kernel.dk, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, Matthew Wilcox Subject: Re: [PATCH 5/7] block: Rework bio_for_each_folio_all() Message-ID: References: <20230525214822.2725616-1-kent.overstreet@linux.dev> <20230525214822.2725616-6-kent.overstreet@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, May 26, 2023 at 10:36:03AM +1000, Dave Chinner wrote: > On Thu, May 25, 2023 at 05:48:20PM -0400, Kent Overstreet wrote: > > This reimplements bio_for_each_folio_all() on top of the newly-reworked > > bvec_iter_all, and since it's now trivial we also provide > > bio_for_each_folio. > > > > Signed-off-by: Kent Overstreet > > Cc: Matthew Wilcox > > Cc: linux-block@vger.kernel.org > > --- > > fs/crypto/bio.c | 9 +++-- > > fs/iomap/buffered-io.c | 14 ++++--- > > fs/verity/verify.c | 9 +++-- > > include/linux/bio.h | 91 +++++++++++++++++++++--------------------- > > include/linux/bvec.h | 15 +++++-- > > 5 files changed, 75 insertions(+), 63 deletions(-) > .... > > diff --git a/include/linux/bio.h b/include/linux/bio.h > > index f86c7190c3..7ced281734 100644 > > --- a/include/linux/bio.h > > +++ b/include/linux/bio.h > > @@ -169,6 +169,42 @@ static inline void bio_advance(struct bio *bio, unsigned int nbytes) > > #define bio_for_each_segment(bvl, bio, iter) \ > > __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) > > > > +struct folio_vec { > > + struct folio *fv_folio; > > + size_t fv_offset; > > + size_t fv_len; > > +}; > > Can we drop the "fv_" variable prefix here? It's just unnecessary > verbosity when we know we have a folio_vec structure. i.e fv->folio > is easier to read and type than fv->fv_folio... That's actually one of the things I like about bio/biovec, it's been handy in the past for grepping and block layer refactorings... (I would _kill_ for a tool that let me do that kind of type-aware grep. ctags can in theory produce that kind of an index but I never figured out how to get vim to use it properly. I believe the lsp-server stuff that uses the compiler as a backend can do it; I've started using that stuff for Rust coding and it works amazingly, don't think I've tried it for struct members - I wonder if that stuff works at all on a codebase the size of the kernel or just dies...) > Hmmm, this is probably not a good name considering "struct pagevec" is > something completely different - the equivalent is "struct > folio_batch" but I can see this being confusing for people who > largely expect some symmetry between page<->folio naming > conventions... Yeah, good point. folio_seg, perhaps? (I think Matthew may have already made that suggestion...) > Also, why is this in bio.h and not in a mm/folio related header > file? Is it worth moving it there considering it's only used in bio.h/bvec.h? Perhaps we could keep it where it's used for now and move it if it gains more users?