From: Christoph Hellwig <hch@infradead.org>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Joanne Koong <joannelkoong@gmail.com>,
brauner@kernel.org, miklos@szeredi.hu, hch@infradead.org,
linux-fsdevel@vger.kernel.org, kernel-team@meta.com,
linux-xfs@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH v1 04/16] iomap: use iomap_iter->private for stashing read/readahead bio
Date: Wed, 3 Sep 2025 23:07:13 -0700 [thread overview]
Message-ID: <aLkskcgl3Z91oIVB@infradead.org> (raw)
In-Reply-To: <20250903203031.GM1587915@frogsfrogsfrogs>
On Wed, Sep 03, 2025 at 01:30:31PM -0700, Darrick J. Wong wrote:
> On Fri, Aug 29, 2025 at 04:56:15PM -0700, Joanne Koong wrote:
> > Use the iomap_iter->private field for stashing any read/readahead bios
> > instead of defining the bio as part of the iomap_readpage_ctx struct.
> > This makes the read/readahead interface more generic. Some filesystems
> > that will be using iomap for read/readahead may not have CONFIG_BLOCK
> > set.
>
> Sorry, but I don't like abusing iomap_iter::private because (a) it's a
> void pointer which means shenanigans; and (b) private exists to store
> some private data for an iomap caller, not iomap itself.
I don't think we can do without the void pointer for a generic
lower library, but I fully agree on not using iomap_iter::private.
We'll need that for something caller provided sooner or later.
The right way ahead is to have a void pointer for the I/O-type specific
context in iomap_readpage_ctx, and then hopefully reasonable type safe
wrappers around it.
next prev parent reply other threads:[~2025-09-04 6:07 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-29 23:56 [PATCH v1 00/16] fuse: use iomap for buffered reads + readahead Joanne Koong
2025-08-29 23:56 ` [PATCH v1 01/16] iomap: move async bio read logic into helper function Joanne Koong
2025-09-03 20:16 ` Darrick J. Wong
2025-09-04 6:00 ` Christoph Hellwig
2025-09-04 21:44 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 02/16] iomap: rename cur_folio_in_bio to folio_unlocked Joanne Koong
2025-09-03 20:26 ` [PATCH v1 02/16] iomap: rename cur_folio_in_bio to folio_unlockedOM Darrick J. Wong
2025-09-04 6:03 ` Christoph Hellwig
2025-09-04 22:06 ` Joanne Koong
2025-09-05 15:03 ` Darrick J. Wong
2025-08-29 23:56 ` [PATCH v1 03/16] iomap: refactor read/readahead completion Joanne Koong
2025-09-04 6:05 ` Christoph Hellwig
2025-09-04 23:16 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 04/16] iomap: use iomap_iter->private for stashing read/readahead bio Joanne Koong
2025-09-03 20:30 ` Darrick J. Wong
2025-09-04 6:07 ` Christoph Hellwig [this message]
2025-09-04 22:20 ` Joanne Koong
2025-09-04 23:15 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 05/16] iomap: propagate iomap_read_folio() error to caller Joanne Koong
2025-09-03 20:32 ` Darrick J. Wong
2025-09-04 6:09 ` Christoph Hellwig
2025-09-04 21:13 ` Matthew Wilcox
2025-09-22 16:49 ` Joanne Koong
2025-09-23 18:34 ` Darrick J. Wong
2025-09-24 23:12 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 06/16] iomap: move read/readahead logic out of CONFIG_BLOCK guard Joanne Koong
2025-08-29 23:56 ` [PATCH v1 07/16] iomap: iterate through entire folio in iomap_readpage_iter() Joanne Koong
2025-09-03 20:43 ` Darrick J. Wong
2025-09-04 22:37 ` Joanne Koong
2025-09-04 6:14 ` Christoph Hellwig
2025-09-04 22:45 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 08/16] iomap: rename iomap_readpage_iter() to iomap_readfolio_iter() Joanne Koong
2025-09-04 6:15 ` Christoph Hellwig
2025-09-04 22:47 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 09/16] iomap: rename iomap_readpage_ctx struct to iomap_readfolio_ctx Joanne Koong
2025-09-03 20:44 ` Darrick J. Wong
2025-08-29 23:56 ` [PATCH v1 10/16] iomap: add iomap_start_folio_read() helper Joanne Koong
2025-09-03 20:52 ` Darrick J. Wong
2025-08-29 23:56 ` [PATCH v1 11/16] iomap: make start folio read and finish folio read public APIs Joanne Koong
2025-09-03 20:53 ` Darrick J. Wong
2025-09-04 6:15 ` Christoph Hellwig
2025-08-29 23:56 ` [PATCH v1 12/16] iomap: add iomap_read_ops for read and readahead Joanne Koong
2025-09-03 21:08 ` Darrick J. Wong
2025-09-04 20:58 ` Joanne Koong
2025-09-04 6:21 ` Christoph Hellwig
2025-09-04 21:38 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 13/16] iomap: add a private arg " Joanne Koong
2025-08-30 1:54 ` Gao Xiang
2025-09-02 21:24 ` Joanne Koong
2025-09-03 1:55 ` Gao Xiang
2025-09-04 23:29 ` Joanne Koong
2025-09-05 2:21 ` Gao Xiang
2025-09-05 15:21 ` Darrick J. Wong
2025-09-08 6:56 ` Gao Xiang
2025-09-03 21:11 ` Darrick J. Wong
2025-08-29 23:56 ` [PATCH v1 14/16] fuse: use iomap for read_folio Joanne Koong
2025-09-03 21:13 ` Darrick J. Wong
2025-08-29 23:56 ` [PATCH v1 15/16] fuse: use iomap for readahead Joanne Koong
2025-09-03 21:17 ` Darrick J. Wong
2025-09-04 19:40 ` Joanne Koong
2025-09-04 19:46 ` Joanne Koong
2025-08-29 23:56 ` [PATCH v1 16/16] fuse: remove fuse_readpages_end() null mapping check Joanne Koong
2025-09-02 9:21 ` Miklos Szeredi
2025-09-02 21:19 ` Joanne Koong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=aLkskcgl3Z91oIVB@infradead.org \
--to=hch@infradead.org \
--cc=brauner@kernel.org \
--cc=djwong@kernel.org \
--cc=joannelkoong@gmail.com \
--cc=kernel-team@meta.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=miklos@szeredi.hu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.