From: Christoph Hellwig <hch@infradead.org>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>,
Jens Axboe <axboe@kernel.dk>, Jooyung Han <jooyung@google.com>,
Alasdair Kergon <agk@redhat.com>,
Mike Snitzer <snitzer@kernel.org>,
Heinz Mauelshagen <heinzm@redhat.com>,
zkabelac@redhat.com, dm-devel@lists.linux.dev,
linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] the dm-loop target
Date: Tue, 4 Mar 2025 05:49:51 -0800 [thread overview]
Message-ID: <Z8cE_4KSKHe5-J3e@infradead.org> (raw)
In-Reply-To: <8adb8df2-0c75-592d-bc3e-5609bb8de8d8@redhat.com>
On Mon, Mar 03, 2025 at 10:03:42PM +0100, Mikulas Patocka wrote:
> Swapfile does ahead of time mapping.
It does. But it is:
a) protected against modification by the S_SWAPFILE flag and checked
for full allocation first
b) something we want to get rid of because even with the above it is
rather problematic
> And I just looked at what swapfile
> does and copied the logic into dm-loop. If swapfile is not broken, how
> could dm-loop be broken?
As said above, swapfile works around the brokenness in ways that you
can't. And just blindly copying old code without understanding it is
never a good idea.
>
> > > Would Jens Axboe agree to merge the dm-loop logic into the existing loop
> > > driver?
> >
> > What logic?
>
> The ahead-of-time mapping.
As said multiple times you can't do that. The block mapping is
file system private information.
next prev parent reply other threads:[~2025-03-04 13:49 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <7d6ae2c9-df8e-50d0-7ad6-b787cb3cfab4@redhat.com>
2025-03-03 13:59 ` [PATCH] the dm-loop target Christoph Hellwig
[not found] ` <CAM23VxprhJgOPfhxQf6QNWzHd6+-ZwbjSo-oMHCD2WDQiKntMg@mail.gmail.com>
2025-03-03 15:13 ` Christoph Hellwig
2025-03-03 15:22 ` Matthew Wilcox
2025-03-03 15:31 ` Christoph Hellwig
[not found] ` <CAM23VxprSduDDK8qvLVkUt9WWmLMPFjhqKB8X4e6gw7Wv-6R2w@mail.gmail.com>
2025-03-03 17:24 ` Christoph Hellwig
[not found] ` <CAM23Vxoxyrf9nwJd1Xe8uncAPiyK8yaNZNsugwX8p=qo1n6yVg@mail.gmail.com>
2025-03-04 13:52 ` Christoph Hellwig
2025-03-03 16:16 ` Mikulas Patocka
2025-03-03 17:24 ` Christoph Hellwig
2025-03-03 21:03 ` Mikulas Patocka
2025-03-04 2:13 ` Dave Chinner
2025-03-04 11:18 ` Mikulas Patocka
2025-03-04 13:50 ` Christoph Hellwig
2025-03-05 0:01 ` Dave Chinner
2025-03-07 15:21 ` Mikulas Patocka
2025-03-08 3:49 ` Darrick J. Wong
2025-03-08 20:45 ` Mikulas Patocka
2025-03-09 0:05 ` Ming Lei
2025-03-10 11:18 ` Mikulas Patocka
2025-03-11 1:27 ` Dave Chinner
2025-03-11 10:43 ` Ming Lei
2025-03-12 2:34 ` Dave Chinner
2025-03-12 6:24 ` Christoph Hellwig
2025-03-12 8:26 ` Ming Lei
2025-03-13 1:36 ` Ming Lei
2025-03-13 16:36 ` Mikulas Patocka
2025-03-18 4:27 ` Dave Chinner
2025-03-18 7:57 ` Christoph Hellwig
2025-03-18 9:34 ` Ming Lei
2025-03-20 7:08 ` Christoph Hellwig
2025-03-20 7:41 ` Ming Lei
2025-03-20 14:22 ` Christoph Hellwig
2025-03-20 14:36 ` Ming Lei
2025-03-25 10:15 ` Dave Chinner
2025-03-25 12:23 ` Ming Lei
2025-03-09 0:16 ` Ming Lei
2025-03-10 11:20 ` Mikulas Patocka
2025-03-04 13:49 ` Christoph Hellwig [this message]
[not found] ` <CAM23Vxr=fKy-0L1R5P-5h6A95acKT_d=CC1E+TAzAs8v6q9gHw@mail.gmail.com>
2025-03-04 16:04 ` Christoph Hellwig
[not found] ` <CAM23VxqJX46DCpCiH5qxPpDLtMVg87Ba8sx55aQ4hvt-XaHzuQ@mail.gmail.com>
2025-03-04 17:17 ` Christoph Hellwig
2025-03-12 13:26 ` Kent Overstreet
2025-03-12 14:20 ` Christoph Hellwig
2025-03-12 16:09 ` Kent Overstreet
2025-03-13 12:44 ` Christoph Hellwig
2025-03-13 16:21 ` Mikulas Patocka
2025-03-13 16:33 ` Kent Overstreet
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