From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752382Ab3A2W64 (ORCPT ); Tue, 29 Jan 2013 17:58:56 -0500 Received: from mail-ia0-f179.google.com ([209.85.210.179]:40365 "EHLO mail-ia0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751647Ab3A2W6v (ORCPT ); Tue, 29 Jan 2013 17:58:51 -0500 MIME-Version: 1.0 X-Originating-IP: [188.6.195.195] In-Reply-To: <20130125182407.10037.26333.stgit@maximpc.sw.ru> References: <20130125181700.10037.29163.stgit@maximpc.sw.ru> <20130125182407.10037.26333.stgit@maximpc.sw.ru> Date: Tue, 29 Jan 2013 23:58:51 +0100 Message-ID: Subject: Re: [PATCH 08/14] fuse: Flush files on wb close From: Miklos Szeredi To: "Maxim V. Patlasov" Cc: dev@parallels.com, xemul@parallels.com, fuse-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, jbottomley@parallels.com, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, devel@openvz.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 25, 2013 at 7:24 PM, Maxim V. Patlasov wrote: > Any write request requires a file handle to report to the userspace. Thus > when we close a file (and free the fuse_file with this info) we have to > flush all the outstanding writeback cache. Note, that simply calling the > filemap_write_and_wait() is not enough since fuse finishes page writeback > immediately and thus the -wait part of the mentioned call will be no-op. > Do real wait on per-inode writepages list. > > Signed-off-by: Maxim Patlasov > Signed-off-by: Pavel Emelyanov > --- > fs/fuse/file.c | 26 +++++++++++++++++++++++++- > 1 files changed, 25 insertions(+), 1 deletions(-) > > diff --git a/fs/fuse/file.c b/fs/fuse/file.c > index 4f8fa45..496e74c 100644 > --- a/fs/fuse/file.c > +++ b/fs/fuse/file.c > @@ -138,6 +138,12 @@ static void fuse_file_put(struct fuse_file *ff, bool sync) > } > } > > +static void __fuse_file_put(struct fuse_file *ff) > +{ > + if (atomic_dec_and_test(&ff->count)) > + BUG(); > +} > + > int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file, > bool isdir) > { > @@ -286,8 +292,23 @@ static int fuse_open(struct inode *inode, struct file *file) > return fuse_open_common(inode, file, false); > } > > +static void fuse_flush_writeback(struct inode *inode, struct file *file) > +{ > + struct fuse_conn *fc = get_fuse_conn(inode); > + struct fuse_inode *fi = get_fuse_inode(inode); > + > + filemap_write_and_wait(file->f_mapping); > + wait_event(fi->page_waitq, list_empty_careful(&fi->writepages)); > + spin_unlock_wait(&fc->lock); > +} > + > static int fuse_release(struct inode *inode, struct file *file) > { > + struct fuse_conn *fc = get_fuse_conn(inode); > + > + if (fc->writeback_cache) > + fuse_flush_writeback(inode, file); > + > fuse_release_common(file, FUSE_RELEASE); > > /* return value is ignored by VFS */ > @@ -1343,7 +1364,8 @@ static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req) > > for (i = 0; i < req->num_pages; i++) > __free_page(req->pages[i]); > - fuse_file_put(req->ff, false); > + if (!fc->writeback_cache) > + fuse_file_put(req->ff, false); > } > > static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req) > @@ -1360,6 +1382,8 @@ static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req) > } > bdi_writeout_inc(bdi); > wake_up(&fi->page_waitq); > + if (fc->writeback_cache) > + __fuse_file_put(req->ff); > } I don't see how this belongs in this patch. And I suspect this can be done unconditionally (for the non-writeback-cache case as well), but please move it into a separate patch. Thanks, Miklos