From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J. Bruce Fields" Subject: Re: [PATCH 1/1] nfsd41: use sv_max_mesg for forechannel max sizes Date: Mon, 28 Sep 2009 12:41:58 -0400 Message-ID: <20090928164158.GB13299@fieldses.org> References: <1253755941-4485-1-git-send-email-andros@netapp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-nfs@vger.kernel.org, pnfs@linux-nfs.org To: andros@netapp.com Return-path: Received: from fieldses.org ([174.143.236.118]:37280 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752520AbZI1Qlj (ORCPT ); Mon, 28 Sep 2009 12:41:39 -0400 In-Reply-To: <1253755941-4485-1-git-send-email-andros@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Wed, Sep 23, 2009 at 09:32:21PM -0400, andros@netapp.com wrote: > From: Andy Adamson > > ca_maxresponsesize and ca_maxrequest size include the RPC header. > > sv_max_mesg is sv_max_payolad plus a page for overhead and is used in > svc_init_buffer to allocate server buffer space for both the request and reply. > Note that this means we can service an RPC compound that requires > ca_maxrequestsize (MAXWRITE) or ca_max_responsesize (MAXREAD) but that we do > not support an RPC compound that requires both ca_maxrequestsize and > ca_maxresponsesize. Thanks Andy, applied, as follows, with some minor documentation changes. --b. commit ddc04fd4d5163aee9ebdb38a56c365b602e2b7b7 Author: Andy Adamson Date: Wed Sep 23 21:32:21 2009 -0400 nfsd41: use sv_max_mesg for forechannel max sizes ca_maxresponsesize and ca_maxrequest size include the RPC header. sv_max_mesg is sv_max_payolad plus a page for overhead and is used in svc_init_buffer to allocate server buffer space for both the request and reply. Note that this means we can service an RPC compound that requires ca_maxrequestsize (MAXWRITE) or ca_max_responsesize (MAXREAD) but that we do not support an RPC compound that requires both ca_maxrequestsize and ca_maxresponsesize. Signed-off-by: Andy Adamson [bfields@citi.umich.edu: more documentation updates] Signed-off-by: J. Bruce Fields diff --git a/Documentation/filesystems/nfs41-server.txt b/Documentation/filesystems/nfs41-server.txt index 1f95e77..1bd0d0c 100644 --- a/Documentation/filesystems/nfs41-server.txt +++ b/Documentation/filesystems/nfs41-server.txt @@ -213,3 +213,10 @@ The following cases aren't supported yet: DESTROY_CLIENTID, DESTROY_SESSION, EXCHANGE_ID. * DESTROY_SESSION MUST be the final operation in the COMPOUND request. +Nonstandard compound limitations: +* No support for a sessions fore channel RPC compound that requires both a + ca_maxrequestsize request and a ca_maxresponsesize reply, so we may + fail to live up to the promise we made in CREATE_SESSION fore channel + negotiation. +* No more than one IO operation (read, write, readdir) allowed per + compound. diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 2153f9b..fcb9817 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -477,13 +477,14 @@ static int set_forechannel_drc_size(struct nfsd4_channel_attrs *fchan) /* * fchan holds the client values on input, and the server values on output + * sv_max_mesg is the maximum payload plus one page for overhead. */ static int init_forechannel_attrs(struct svc_rqst *rqstp, struct nfsd4_channel_attrs *session_fchan, struct nfsd4_channel_attrs *fchan) { int status = 0; - __u32 maxcount = svc_max_payload(rqstp); + __u32 maxcount = nfsd_serv->sv_max_mesg; /* headerpadsz set to zero in encode routine */