From mboxrd@z Thu Jan  1 00:00:00 1970
From: dong wu <dongwucs@gmail.com>
Subject: linux-raid raid5 delaying write
Date: Thu, 7 Jan 2010 20:18:14 +0800
Message-ID: <6c394cc31001070418w60785400v77e0e7a47b0732fc@mail.gmail.com>
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hello,
In the source code,in order to collect multiple write requests,first
add the requests to delayed_list,
then use plug/unplug to wait.During the waiting time,if other requests
arrive to full a stripe_head buffer,
then compute parity and send write request to low level to deal.
If not so, the requests will be set pre-read mark
stripe_preread_active,then send pre-read request to low level.
I want to know if up level send read request and later a write request
arrive to write the same place of read request before,
will the read request be canceled and return the data of write request?

Best Regards
Dong Wu