From: "Dr. J. Bruce Fields" Subject: Re: [PATCH v4] nfsd: Use vfs_fsync_range() in nfsd_commit Date: Fri, 29 Jan 2010 18:53:54 -0500 Message-ID: <20100129235354.GA30852@fieldses.org> References: <1264796353.3644.4.camel@localhost> <20100129205022.GA14449@infradead.org> <1264798623.3644.18.camel@localhost> <1264799906.3644.21.camel@localhost> <20100129212706.GA28361@infradead.org> <1264801465.3644.30.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Christoph Hellwig , linux-nfs@vger.kernel.org To: Trond Myklebust Return-path: Received: from fieldses.org ([174.143.236.118]:51910 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752903Ab0A2Xxy (ORCPT ); Fri, 29 Jan 2010 18:53:54 -0500 In-Reply-To: <1264801465.3644.30.camel@localhost> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, Jan 29, 2010 at 04:44:25PM -0500, Trond Myklebust wrote: > nfsd: Use vfs_fsync_range() in nfsd_commit > > From: Trond Myklebust > > The NFS COMMIT operation allows the client to specify the exact byte range > that it wishes to sync to disk in order to optimise server performance. > > Signed-off-by: Trond Myklebust > Reviewed-by: Christoph Hellwig Applied, thanks! --b. > --- > > fs/nfsd/vfs.c | 30 ++++++++++++++++++++---------- > 1 files changed, 20 insertions(+), 10 deletions(-) > > > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > index 79d216f..ed024d3 100644 > --- a/fs/nfsd/vfs.c > +++ b/fs/nfsd/vfs.c > @@ -1141,8 +1141,9 @@ out: > #ifdef CONFIG_NFSD_V3 > /* > * Commit all pending writes to stable storage. > - * Strictly speaking, we could sync just the indicated file region here, > - * but there's currently no way we can ask the VFS to do so. > + * > + * Note: we only guarantee that data that lies within the range specified > + * by the 'offset' and 'count' parameters will be synced. > * > * Unfortunately we cannot lock the file to make sure we return full WCC > * data to the client, as locking happens lower down in the filesystem. > @@ -1152,23 +1153,32 @@ nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp, > loff_t offset, unsigned long count) > { > struct file *file; > - __be32 err; > + loff_t end = LLONG_MAX; > + __be32 err = nfserr_inval; > > - if ((u64)count > ~(u64)offset) > - return nfserr_inval; > + if (offset < 0) > + goto out; > + if (count != 0) { > + end = offset + (loff_t)count - 1; > + if (end < offset) > + goto out; > + } > > err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file); > if (err) > - return err; > + goto out; > if (EX_ISSYNC(fhp->fh_export)) { > - if (file->f_op && file->f_op->fsync) { > - err = nfserrno(vfs_fsync(file, file->f_path.dentry, 0)); > - } else { > + int err2 = vfs_fsync_range(file, file->f_path.dentry, > + offset, end, 0); > + > + if (err2 != -EINVAL) > + err = nfserrno(err2); > + else > err = nfserr_notsupp; > - } > } > > nfsd_close(file); > +out: > return err; > } > #endif /* CONFIG_NFSD_V3 */ >