From owner-freebsd-hackers  Fri Oct 18 23:13:41 2002
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Date: Fri, 18 Oct 2002 23:13:40 -0700 (PDT)
From: Matthew Dillon <dillon@apollo.backplane.com>
Message-Id: <200210190613.g9J6Debh023134@apollo.backplane.com>
To: Maxim Sobolev <sobomax@FreeBSD.ORG>
Cc: hackers@FreeBSD.ORG
Subject: Re: Patch to allow a driver to report unrecoverable write errors to the buf layer
References: <3DB048B5.21097613@FreeBSD.org> <200210181807.g9II7cBY024485@apollo.backplane.com> <3DB0516F.9BE00F57@FreeBSD.org> <200210181835.g9IIZsBX061970@apollo.backplane.com> <20021019051202.GB14922@vega.vega.com>
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:
:Hmm, the current approach doesn't look all that "right" to me, because we are
:retrying operation even though the upper-layer code that initiated it was
:already notified about the failure (e.g. received EIO), so that it should not
:assume that the data was actually written successfully. Or I am missing
:something?
:
:-Maxim

    Yah, most writes issued through the buffer cache are asynchronous or
    delayed.  So the VFS layer that initiated the write is not necessarily
    going to be notified of a failure.  Thus the failure notification does
    not help us here.

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>

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