From: NeilBrown <neilb@suse.com>
To: linux-nfs@vger.kernel.org
Date: Wed, 05 Sep 2018 08:47:23 +1000
Subject: NFSv4.1 session reset needs to update ->rsize and ->wsize - how???
Message-ID: <87r2i8vq10.fsf@notabene.neil.brown.name>
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With NFSv4.1, the server specifies max_rqst_sz and max_resp_sz in the
reply to CREATE session.

If the client finds it needs to call nfs4_reset_session(), it might get
smaller sizes back, so any pending read/writes would need to be resized.

However, I cannot see how the retry handling for reads/writes has any
chance to change the size.  It looks like a request is broken up to
match the original ->rsize and ->wsize, then those individual IO
requests can be retried, but the higher level request is never
re-evaluated in light of a new size.

Am I missing something, or is this not supported at present?
If it isn't supported, any suggestions on how best to handle a
reduction of the rsize/wsize ??

Thanks,
NeilBrown

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