From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: [PATCH 07/20] nfs: add a comment explaining the use of PG_private in the NFS client Date: Tue, 12 Sep 2006 17:25:49 +0200 Message-ID: <20060912144903.770953000@chello.nl> References: <20060912143049.278065000@chello.nl> Cc: Linus Torvalds , Andrew Morton , David Miller , Rik van Riel , Daniel Phillips , Peter Zijlstra , Trond Myklebust Return-path: Received: from amsfep17-int.chello.nl ([213.46.243.15]:53137 "EHLO amsfep20-int.chello.nl") by vger.kernel.org with ESMTP id S1751425AbWILPux (ORCPT ); Tue, 12 Sep 2006 11:50:53 -0400 To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Content-Disposition: inline; filename=nfs_PG_private_comment.patch Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Add a little comment explaining the use of PG_private in the NFS client. Signed-off-by: Peter Zijlstra CC: Trond Myklebust --- fs/nfs/write.c | 5 +++++ 1 file changed, 5 insertions(+) Index: linux-2.6/fs/nfs/write.c =================================================================== --- linux-2.6.orig/fs/nfs/write.c +++ linux-2.6/fs/nfs/write.c @@ -417,6 +417,11 @@ static int nfs_inode_add_request(struct if (nfs_have_delegation(inode, FMODE_WRITE)) nfsi->change_attr++; } + /* + * The PG_private bit is unfortunately needed if we want to fix the + * hole in the mmap semantics. If we do not set it, then the VM will + * fail to call the "releasepage" address ops. + */ SetPagePrivate(req->wb_page); nfsi->npages++; atomic_inc(&req->wb_count); --