Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:49788 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752064AbeDJUVZ (ORCPT ); Tue, 10 Apr 2018 16:21:25 -0400 Date: Tue, 10 Apr 2018 16:21:24 -0400 From: "J. Bruce Fields" To: Olga Kornievskaia Cc: "J. Bruce Fields" , Olga Kornievskaia , linux-nfs Subject: Re: [PATCH v7 10/10] NFSD stop queued async copies on client shutdown Message-ID: <20180410202123.GB5685@parsley.fieldses.org> References: <20180220164229.65404-1-kolga@netapp.com> <20180220164229.65404-11-kolga@netapp.com> <20180308170511.GF10782@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, Apr 10, 2018 at 04:09:09PM -0400, Olga Kornievskaia wrote: > I have a question. I’m testing how the code works in > nfsd4_shutdown_copy. I have disabled canceling the copy (just > returning ok) and so then the client can stop its copy and do the > close and then I can issue an unmount. What I see is that the server > returns “err_delay” until the copy finishes. That’s because in > nfsd4_destroy_clientid() it calls mark_client_expired_locked() which > checks the refcount on the client structure and since copy holds a > reference server returns err_delay. Once the copy finished and > decrements the reference, and nfsd4_destroy_clientid() gets past that > then calling nfsd4_shutdown_copy() doesn’t find any copies. > > Should the logic of nfsd4_destroy_clientid() be changed to stop copies > then instead of during destruction of the client structure? Oh, good question, I don't know. Thinking about it.... DESTROY_CLIENTID doesn't throw away all the client's state for it, it's only meant to be called after the client has already cleaned up everything else. So: https://tools.ietf.org/html/rfc5661#section-18.50.3 If there are sessions (both idle and non-idle), opens, locks, delegations, layouts, and/or wants (Section 18.49) associated with the unexpired lease of the client ID, the server MUST return NFS4ERR_CLIENTID_BUSY. My feeling is that "ongoing copies" also belongs on that list. So the server behavior you're seeing sounds correct to me--the client should cancel any ongoing copies before calling DESTROY_CLIENTID. --b.