From: Trond Myklebust Subject: Re: [PATCH] knfsd: Correct reserved reply space for read requests. Date: Thu, 30 Mar 2006 02:17:31 -0500 Message-ID: <1143703051.8129.2.camel@lade.trondhjem.org> References: <20060330165307.25307.patches@notabene> <1060330055350.25337@suse.de> Mime-Version: 1.0 Content-Type: text/plain Cc: Andrew Morton , nfs@lists.sourceforge.net, linux-kernel@vger.kernel.org Return-path: To: NeilBrown In-Reply-To: <1060330055350.25337@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Thu, 2006-03-30 at 16:53 +1100, NeilBrown wrote: > Single patch for nfsd in 2.6.16. As the comment say, it is sensible > for this to sit in -mm for a while just in case. > > ### Comments for Changeset > > NFSd makes sure there is enough space to hold the maximum possible > reply before accepting a request. The units for this maximum is > (4byte) words. However in three places, particularly for read > request, the number given is a number of bytes. > > This means too much space is reserved which is slightly wasteful. > > This is the sort of patch that could uncover a deeper bug, and it is > not critical, so it would be best for it to spend a while in -mm before going in to mainline. > > Discovered-by: "Eivind Sarto" > > Cc: "Eivind Sarto" > > Signed-off-by: Neil Brown > > ### Diffstat output > ./fs/nfsd/nfs3proc.c | 2 +- > ./fs/nfsd/nfs4proc.c | 2 +- > ./fs/nfsd/nfsproc.c | 2 +- > 3 files changed, 3 insertions(+), 3 deletions(-) > > diff ./fs/nfsd/nfs3proc.c~current~ ./fs/nfsd/nfs3proc.c > --- ./fs/nfsd/nfs3proc.c~current~ 2006-03-30 16:48:30.000000000 +1100 > +++ ./fs/nfsd/nfs3proc.c 2006-03-30 16:48:58.000000000 +1100 > @@ -682,7 +682,7 @@ static struct svc_procedure nfsd_proced > PROC(lookup, dirop, dirop, fhandle2, RC_NOCACHE, ST+FH+pAT+pAT), > PROC(access, access, access, fhandle, RC_NOCACHE, ST+pAT+1), > PROC(readlink, readlink, readlink, fhandle, RC_NOCACHE, ST+pAT+1+NFS3_MAXPATHLEN/4), > - PROC(read, read, read, fhandle, RC_NOCACHE, ST+pAT+4+NFSSVC_MAXBLKSIZE), > + PROC(read, read, read, fhandle, RC_NOCACHE, ST+pAT+4+NFSSVC_MAXBLKSIZE/4), Hmm... Wouldn't it be safer to use XDR_QUADLEN()? I doubt that we will ever set a NFSSVC_MAXBLKSIZE that is not divisible by 4, but... > PROC(write, write, write, fhandle, RC_REPLBUFF, ST+WC+4), > PROC(create, create, create, fhandle2, RC_REPLBUFF, ST+(1+FH+pAT)+WC), > PROC(mkdir, mkdir, create, fhandle2, RC_REPLBUFF, ST+(1+FH+pAT)+WC), > > diff ./fs/nfsd/nfs4proc.c~current~ ./fs/nfsd/nfs4proc.c > --- ./fs/nfsd/nfs4proc.c~current~ 2006-03-30 16:48:30.000000000 +1100 > +++ ./fs/nfsd/nfs4proc.c 2006-03-30 16:48:58.000000000 +1100 > @@ -973,7 +973,7 @@ struct nfsd4_voidargs { int dummy; }; > */ > static struct svc_procedure nfsd_procedures4[2] = { > PROC(null, void, void, void, RC_NOCACHE, 1), > - PROC(compound, compound, compound, compound, RC_NOCACHE, NFSD_BUFSIZE) > + PROC(compound, compound, compound, compound, RC_NOCACHE, NFSD_BUFSIZE/4) Ditto... > }; > > struct svc_version nfsd_version4 = { > > diff ./fs/nfsd/nfsproc.c~current~ ./fs/nfsd/nfsproc.c > --- ./fs/nfsd/nfsproc.c~current~ 2006-03-30 16:48:30.000000000 +1100 > +++ ./fs/nfsd/nfsproc.c 2006-03-30 16:48:58.000000000 +1100 > @@ -553,7 +553,7 @@ static struct svc_procedure nfsd_proced > PROC(none, void, void, none, RC_NOCACHE, ST), > PROC(lookup, diropargs, diropres, fhandle, RC_NOCACHE, ST+FH+AT), > PROC(readlink, readlinkargs, readlinkres, none, RC_NOCACHE, ST+1+NFS_MAXPATHLEN/4), > - PROC(read, readargs, readres, fhandle, RC_NOCACHE, ST+AT+1+NFSSVC_MAXBLKSIZE), > + PROC(read, readargs, readres, fhandle, RC_NOCACHE, ST+AT+1+NFSSVC_MAXBLKSIZE/4), > PROC(none, void, void, none, RC_NOCACHE, ST), > PROC(write, writeargs, attrstat, fhandle, RC_REPLBUFF, ST+AT), > PROC(create, createargs, diropres, fhandle, RC_REPLBUFF, ST+FH+AT), Cheers, Trond