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To: Andriy Gapon <avg@FreeBSD.org>
cc: Warner Losh <imp@bsdimp.com>,
 "freebsd-arch@freebsd.org" <freebsd-arch@freebsd.org>,
 freebsd-geom@freebsd.org
Subject: Re: geom->access problem and workaround
In-reply-to: <5e416eb6-0e79-1419-f09a-eb747215dc28@FreeBSD.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <809d9254-ee56-59d8-69a4-08838e985cea@FreeBSD.org>
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Date: Fri, 23 Mar 2018 09:30:03 +0000
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--------
In message <5e416eb6-0e79-1419-f09a-eb747215dc28@FreeBSD.org>, Andriy Gapo=
n writes:
>On 12/03/2018 20:07, Poul-Henning Kamp wrote:
>> If we want to have an architectural sound way to do slow operations
>> before any "user-I/O" is initiated, the right way to do so is to
>> define new BIO_OPEN and BIO_CLOSE  operation, and insist via asserts
>> than all BIO_{READ|WRITE|DELETE} are wrapped in these.

>What do you think?

I don't see that changing anything...

GEOM rests on a set of assumptions, if you violate them, you get panics.

-- =

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    =

Never attribute to malice what can adequately be explained by incompetence=
.