Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764978AbZDBGmd (ORCPT ); Thu, 2 Apr 2009 02:42:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752401AbZDBGmW (ORCPT ); Thu, 2 Apr 2009 02:42:22 -0400 Received: from victor.provo.novell.com ([137.65.250.26]:50755 "EHLO victor.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750975AbZDBGmU (ORCPT ); Thu, 2 Apr 2009 02:42:20 -0400 Message-ID: <49D45E42.3050502@suse.de> Date: Thu, 02 Apr 2009 12:12:10 +0530 From: Suresh Jayaraman User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Mathieu Desnoyers CC: Trond.Myklebust@netapp.com, linux-nfs@vger.kernel.org, linux-embedded@vger.kernel.org, LKML , ltt-dev@lists.casi.polymtl.ca Subject: Re: [PATCH] nfs: add support for splice writes References: <49D45974.2060202@suse.de> <20090402063235.GB24846@Krystal> In-Reply-To: <20090402063235.GB24846@Krystal> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3295 Lines: 94 Mathieu Desnoyers wrote: > * Suresh Jayaraman (sjayaraman@suse.de) wrote: >> This patch attempts to add splice writes support. In essence, it just >> calls generic_file_splice_write() after doing a little sanity check. >> This would allow LTTng users that are using NFS to store trace data. >> There could be more applications that could be benefitted too. >> >> I have tested this using the Jens' test program and have found no >> real issues. The test program is inlined below: >> > > There is just a small checkpatch nit that I'll fix directly in place in > the LTTng tree. > > WARNING: %Ld/%Lu are not-standard C, use %lld/%llu > #93: FILE: fs/nfs/file.c:564: > + dprintk("NFS splice_write(%s/%s, %lu@%Lu)\n", > > total: 0 errors, 1 warnings, 42 lines checked > Yes, I noticed it. There are quite a few places in nfs code where we happened to use that (that doesn't imply that it shouldn't be fixed), so I thought it's OK. > That's great ! I'll pull it in the LTTng tree so my users can try it. > They currently cannot write LTTng traces to NFS mounts anyway. Yes, please report the test results. Would appreciate it very much. Thanks, >> >> diff --git a/fs/nfs/file.c b/fs/nfs/file.c >> index 90f292b..13d6a00 100644 >> --- a/fs/nfs/file.c >> +++ b/fs/nfs/file.c >> @@ -47,6 +47,9 @@ static ssize_t nfs_file_splice_read(struct file *filp, loff_t *ppos, >> size_t count, unsigned int flags); >> static ssize_t nfs_file_read(struct kiocb *, const struct iovec *iov, >> unsigned long nr_segs, loff_t pos); >> +static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe, >> + struct file *filp, loff_t *ppos, >> + size_t count, unsigned int flags); >> static ssize_t nfs_file_write(struct kiocb *, const struct iovec *iov, >> unsigned long nr_segs, loff_t pos); >> static int nfs_file_flush(struct file *, fl_owner_t id); >> @@ -76,6 +79,7 @@ const struct file_operations nfs_file_operations = { >> .lock = nfs_lock, >> .flock = nfs_flock, >> .splice_read = nfs_file_splice_read, >> + .splice_write = nfs_file_splice_write, >> .check_flags = nfs_check_flags, >> .setlease = nfs_setlease, >> }; >> @@ -550,6 +554,26 @@ out_swapfile: >> goto out; >> } >> >> +static ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe, >> + struct file *filp, loff_t *ppos, >> + size_t count, unsigned int flags) >> +{ >> + struct dentry *dentry = filp->f_path.dentry; >> + struct inode *inode = dentry->d_inode; >> + >> + dprintk("NFS splice_write(%s/%s, %lu@%Lu)\n", >> + dentry->d_parent->d_name.name, dentry->d_name.name, >> + (unsigned long) count, (unsigned long long) *ppos); >> + >> + if (IS_SWAPFILE(inode)) { >> + printk(KERN_INFO "NFS: attempt to write to active swap" >> + "file!\n"); >> + return -EBUSY; >> + } >> + >> + return generic_file_splice_write(pipe, filp, ppos, count, flags); >> +} >> + >> static int do_getlk(struct file *filp, int cmd, struct file_lock *fl) >> { >> struct inode *inode = filp->f_mapping->host; >> > -- Suresh Jayaraman -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/