From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A8998BEE; Thu, 18 Sep 2025 22:31:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758234692; cv=none; b=Kphw2IR58hjGk+tcO6zXAgCGXBCMzKK1x+x1/O6+++zDELg6rKh5BcW6m/pTjQUyfcxB7uYqbU6aJqUW4rowr4az5PaQq/M4fT3XbhOSIU4kTbudQ3OUni6utp7XvlYR1JFSl3noRTjXkaqATaaY9bHHUkl9uVN6WJWSxuXJs70= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758234692; c=relaxed/simple; bh=cXNx/gAH9f1jvWsTEILCAoIU9qzvSQeAIYdhjVNy1wA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EsbcVtBWLvHPL6TGqpgnQUMOmo2qS5y5zrFneikigWWVsGWqPTyS2CounYfCkpNRYcZUcTD1eT133xl7YMcjrTlAD821RCrYemW1shnfPJxQP492P+ShQqKMV9hlcKa04jaxSLEvm1Y6/OVQI1ih1x3XoRP0ydHx580xcu76nkA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LypBu7KJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LypBu7KJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CAA15C4CEE7; Thu, 18 Sep 2025 22:31:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758234691; bh=cXNx/gAH9f1jvWsTEILCAoIU9qzvSQeAIYdhjVNy1wA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LypBu7KJ1IBDKjeIUbjdI3SK/Y4AyNrpYKhIHA141RTlm2dRSu1x+BuCmDBBLgegj EPLpB0r/Lsjiye3geNky7YxNx5ctV8SngLN0o+InfY4QX12C2Ei9sU/YDXGdMHY65s VTdmmzWwOQDt+y5ND5YP7Q4AT7hGCGd36bmhR8PPjS6GtUcuiplxdRdZ9EALRUc9Vr M3ZXOBP50E9G+/iWVRaWDuPZdIG/NZzMrbWnUmKKYx+iFipqMuQx04lXuCiPqS7O9k UsJh4uJE4n5RPDADtS0D5rcAfm7PkoOJjFHjK2cb55GneqkwR54lRT3KqEYy4mibE7 0gaoKSLR4iGvQ== Date: Thu, 18 Sep 2025 15:31:31 -0700 From: "Darrick J. Wong" To: Joanne Koong Cc: brauner@kernel.org, miklos@szeredi.hu, hch@infradead.org, hsiangkao@linux.alibaba.com, linux-block@vger.kernel.org, gfs2@lists.linux.dev, linux-fsdevel@vger.kernel.org, kernel-team@meta.com, linux-xfs@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v3 11/15] iomap: move buffered io bio logic into new file Message-ID: <20250918223131.GZ1587915@frogsfrogsfrogs> References: <20250916234425.1274735-1-joannelkoong@gmail.com> <20250916234425.1274735-12-joannelkoong@gmail.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250916234425.1274735-12-joannelkoong@gmail.com> On Tue, Sep 16, 2025 at 04:44:21PM -0700, Joanne Koong wrote: > Move bio logic in the buffered io code into its own file and remove > CONFIG_BLOCK gating for iomap read/readahead. > > Signed-off-by: Christoph Hellwig > Signed-off-by: Joanne Koong /me wonders how long until we end up doing the same thing with the directio code but in the meantime it beats #ifdef everywhere Reviewed-by: "Darrick J. Wong" --D > --- > fs/iomap/Makefile | 3 +- > fs/iomap/bio.c | 90 ++++++++++++++++++++++++++++++++++++++++++ > fs/iomap/buffered-io.c | 90 +----------------------------------------- > fs/iomap/internal.h | 12 ++++++ > 4 files changed, 105 insertions(+), 90 deletions(-) > create mode 100644 fs/iomap/bio.c > > diff --git a/fs/iomap/Makefile b/fs/iomap/Makefile > index f7e1c8534c46..a572b8808524 100644 > --- a/fs/iomap/Makefile > +++ b/fs/iomap/Makefile > @@ -14,5 +14,6 @@ iomap-y += trace.o \ > iomap-$(CONFIG_BLOCK) += direct-io.o \ > ioend.o \ > fiemap.o \ > - seek.o > + seek.o \ > + bio.o > iomap-$(CONFIG_SWAP) += swapfile.o > diff --git a/fs/iomap/bio.c b/fs/iomap/bio.c > new file mode 100644 > index 000000000000..8a51c9d70268 > --- /dev/null > +++ b/fs/iomap/bio.c > @@ -0,0 +1,90 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2010 Red Hat, Inc. > + * Copyright (C) 2016-2023 Christoph Hellwig. > + */ > +#include > +#include > +#include "internal.h" > +#include "trace.h" > + > +static void iomap_read_end_io(struct bio *bio) > +{ > + int error = blk_status_to_errno(bio->bi_status); > + struct folio_iter fi; > + > + bio_for_each_folio_all(fi, bio) > + iomap_finish_folio_read(fi.folio, fi.offset, fi.length, error); > + bio_put(bio); > +} > + > +static void iomap_bio_submit_read(struct iomap_read_folio_ctx *ctx) > +{ > + struct bio *bio = ctx->read_ctx; > + > + if (bio) > + submit_bio(bio); > +} > + > +static int iomap_bio_read_folio_range(const struct iomap_iter *iter, > + struct iomap_read_folio_ctx *ctx, size_t plen) > +{ > + struct folio *folio = ctx->cur_folio; > + const struct iomap *iomap = &iter->iomap; > + loff_t pos = iter->pos; > + size_t poff = offset_in_folio(folio, pos); > + loff_t length = iomap_length(iter); > + sector_t sector; > + struct bio *bio = ctx->read_ctx; > + > + iomap_start_folio_read(folio, plen); > + > + sector = iomap_sector(iomap, pos); > + if (!bio || bio_end_sector(bio) != sector || > + !bio_add_folio(bio, folio, plen, poff)) { > + gfp_t gfp = mapping_gfp_constraint(folio->mapping, GFP_KERNEL); > + gfp_t orig_gfp = gfp; > + unsigned int nr_vecs = DIV_ROUND_UP(length, PAGE_SIZE); > + > + if (bio) > + submit_bio(bio); > + > + if (ctx->rac) /* same as readahead_gfp_mask */ > + gfp |= __GFP_NORETRY | __GFP_NOWARN; > + bio = bio_alloc(iomap->bdev, bio_max_segs(nr_vecs), REQ_OP_READ, > + gfp); > + /* > + * If the bio_alloc fails, try it again for a single page to > + * avoid having to deal with partial page reads. This emulates > + * what do_mpage_read_folio does. > + */ > + if (!bio) > + bio = bio_alloc(iomap->bdev, 1, REQ_OP_READ, orig_gfp); > + if (ctx->rac) > + bio->bi_opf |= REQ_RAHEAD; > + bio->bi_iter.bi_sector = sector; > + bio->bi_end_io = iomap_read_end_io; > + bio_add_folio_nofail(bio, folio, plen, poff); > + ctx->read_ctx = bio; > + } > + return 0; > +} > + > +const struct iomap_read_ops iomap_bio_read_ops = { > + .read_folio_range = iomap_bio_read_folio_range, > + .submit_read = iomap_bio_submit_read, > +}; > +EXPORT_SYMBOL_GPL(iomap_bio_read_ops); > + > +int iomap_bio_read_folio_range_sync(const struct iomap_iter *iter, > + struct folio *folio, loff_t pos, size_t len) > +{ > + const struct iomap *srcmap = iomap_iter_srcmap(iter); > + struct bio_vec bvec; > + struct bio bio; > + > + bio_init(&bio, srcmap->bdev, &bvec, 1, REQ_OP_READ); > + bio.bi_iter.bi_sector = iomap_sector(srcmap, pos); > + bio_add_folio_nofail(&bio, folio, len, offset_in_folio(folio, pos)); > + return submit_bio_wait(&bio); > +} > diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c > index 667a49cb5ae5..72258b0109ec 100644 > --- a/fs/iomap/buffered-io.c > +++ b/fs/iomap/buffered-io.c > @@ -8,6 +8,7 @@ > #include > #include > #include > +#include "internal.h" > #include "trace.h" > > #include "../internal.h" > @@ -352,74 +353,6 @@ void iomap_finish_folio_read(struct folio *folio, size_t off, size_t len, > } > EXPORT_SYMBOL_GPL(iomap_finish_folio_read); > > -#ifdef CONFIG_BLOCK > -static void iomap_read_end_io(struct bio *bio) > -{ > - int error = blk_status_to_errno(bio->bi_status); > - struct folio_iter fi; > - > - bio_for_each_folio_all(fi, bio) > - iomap_finish_folio_read(fi.folio, fi.offset, fi.length, error); > - bio_put(bio); > -} > - > -static void iomap_bio_submit_read(struct iomap_read_folio_ctx *ctx) > -{ > - struct bio *bio = ctx->read_ctx; > - > - if (bio) > - submit_bio(bio); > -} > - > -static int iomap_bio_read_folio_range(const struct iomap_iter *iter, > - struct iomap_read_folio_ctx *ctx, size_t plen) > -{ > - struct folio *folio = ctx->cur_folio; > - const struct iomap *iomap = &iter->iomap; > - loff_t pos = iter->pos; > - size_t poff = offset_in_folio(folio, pos); > - loff_t length = iomap_length(iter); > - sector_t sector; > - struct bio *bio = ctx->read_ctx; > - > - iomap_start_folio_read(folio, plen); > - > - sector = iomap_sector(iomap, pos); > - if (!bio || bio_end_sector(bio) != sector || > - !bio_add_folio(bio, folio, plen, poff)) { > - gfp_t gfp = mapping_gfp_constraint(folio->mapping, GFP_KERNEL); > - gfp_t orig_gfp = gfp; > - unsigned int nr_vecs = DIV_ROUND_UP(length, PAGE_SIZE); > - > - iomap_bio_submit_read(ctx); > - > - if (ctx->rac) /* same as readahead_gfp_mask */ > - gfp |= __GFP_NORETRY | __GFP_NOWARN; > - bio = bio_alloc(iomap->bdev, bio_max_segs(nr_vecs), REQ_OP_READ, > - gfp); > - /* > - * If the bio_alloc fails, try it again for a single page to > - * avoid having to deal with partial page reads. This emulates > - * what do_mpage_read_folio does. > - */ > - if (!bio) > - bio = bio_alloc(iomap->bdev, 1, REQ_OP_READ, orig_gfp); > - if (ctx->rac) > - bio->bi_opf |= REQ_RAHEAD; > - bio->bi_iter.bi_sector = sector; > - bio->bi_end_io = iomap_read_end_io; > - bio_add_folio_nofail(bio, folio, plen, poff); > - ctx->read_ctx = bio; > - } > - return 0; > -} > - > -const struct iomap_read_ops iomap_bio_read_ops = { > - .read_folio_range = iomap_bio_read_folio_range, > - .submit_read = iomap_bio_submit_read, > -}; > -EXPORT_SYMBOL_GPL(iomap_bio_read_ops); > - > /* > * Add a bias to ifs->read_bytes_pending to prevent the read on the folio from > * being ended prematurely. > @@ -623,27 +556,6 @@ void iomap_readahead(const struct iomap_ops *ops, > } > EXPORT_SYMBOL_GPL(iomap_readahead); > > -static int iomap_bio_read_folio_range_sync(const struct iomap_iter *iter, > - struct folio *folio, loff_t pos, size_t len) > -{ > - const struct iomap *srcmap = iomap_iter_srcmap(iter); > - struct bio_vec bvec; > - struct bio bio; > - > - bio_init(&bio, srcmap->bdev, &bvec, 1, REQ_OP_READ); > - bio.bi_iter.bi_sector = iomap_sector(srcmap, pos); > - bio_add_folio_nofail(&bio, folio, len, offset_in_folio(folio, pos)); > - return submit_bio_wait(&bio); > -} > -#else > -static int iomap_bio_read_folio_range_sync(const struct iomap_iter *iter, > - struct folio *folio, loff_t pos, size_t len) > -{ > - WARN_ON_ONCE(1); > - return -EIO; > -} > -#endif /* CONFIG_BLOCK */ > - > /* > * iomap_is_partially_uptodate checks whether blocks within a folio are > * uptodate or not. > diff --git a/fs/iomap/internal.h b/fs/iomap/internal.h > index d05cb3aed96e..7ab1033ab4b7 100644 > --- a/fs/iomap/internal.h > +++ b/fs/iomap/internal.h > @@ -6,4 +6,16 @@ > > u32 iomap_finish_ioend_direct(struct iomap_ioend *ioend); > > +#ifdef CONFIG_BLOCK > +int iomap_bio_read_folio_range_sync(const struct iomap_iter *iter, > + struct folio *folio, loff_t pos, size_t len); > +#else > +int iomap_bio_read_folio_range_sync(const struct iomap_iter *iter, > + struct folio *folio, loff_t pos, size_t len) > +{ > + WARN_ON_ONCE(1); > + return -EIO; > +} > +#endif /* CONFIG_BLOCK */ > + > #endif /* _IOMAP_INTERNAL_H */ > -- > 2.47.3 > >