From: Trond Myklebust Subject: [PATCH 4/5] NFS: Fix race in nfs_set_page_dirty Date: Fri, 20 Apr 2007 16:12:50 -0400 Message-ID: <20070420201250.7897.77055.stgit@heimdal.trondhjem.org> References: <20070420200358.7897.75870.stgit@heimdal.trondhjem.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, Florin Iucha , Adrian Bunk , nfs@lists.sourceforge.net, Andrew Morton , OGAWA Hirofumi To: Linus Torvalds Return-path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list2-new.sourceforge.net with esmtp (Exim 4.43) id 1HezTN-0002oT-9C for nfs@lists.sourceforge.net; Fri, 20 Apr 2007 13:12:49 -0700 Received: from dh166.citi.umich.edu ([141.211.133.166] helo=heimdal.trondhjem.org) by mail.sourceforge.net with esmtp (Exim 4.44) id 1HezTO-0006oP-LH for nfs@lists.sourceforge.net; Fri, 20 Apr 2007 13:12:51 -0700 In-Reply-To: <20070420200358.7897.75870.stgit@heimdal.trondhjem.org> List-Id: "Discussion of NFS under Linux development, interoperability, and testing." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nfs-bounces@lists.sourceforge.net Errors-To: nfs-bounces@lists.sourceforge.net From: Trond Myklebust Protect nfs_set_page_dirty() against races with nfs_inode_add_request. Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 17 ++++++++++++++--- 1 files changed, 14 insertions(+), 3 deletions(-) diff --git a/fs/nfs/write.c b/fs/nfs/write.c index ce5b4a9..7975589 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -388,6 +388,8 @@ static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req) } SetPagePrivate(req->wb_page); set_page_private(req->wb_page, (unsigned long)req); + if (PageDirty(req->wb_page)) + set_bit(PG_NEED_FLUSH, &req->wb_flags); nfsi->npages++; atomic_inc(&req->wb_count); return 0; @@ -407,6 +409,8 @@ static void nfs_inode_remove_request(struct nfs_page *req) set_page_private(req->wb_page, 0); ClearPagePrivate(req->wb_page); radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index); + if (test_and_clear_bit(PG_NEED_FLUSH, &req->wb_flags)) + __set_page_dirty_nobuffers(req->wb_page); nfsi->npages--; if (!nfsi->npages) { spin_unlock(&nfsi->req_lock); @@ -1527,15 +1531,22 @@ int nfs_wb_page(struct inode *inode, struct page* page) int nfs_set_page_dirty(struct page *page) { + spinlock_t *req_lock = &NFS_I(page->mapping->host)->req_lock; struct nfs_page *req; + int ret; - req = nfs_page_find_request(page); + spin_lock(req_lock); + req = nfs_page_find_request_locked(page); if (req != NULL) { /* Mark any existing write requests for flushing */ - set_bit(PG_NEED_FLUSH, &req->wb_flags); + ret = !test_and_set_bit(PG_NEED_FLUSH, &req->wb_flags); + spin_unlock(req_lock); nfs_release_request(req); + return ret; } - return __set_page_dirty_nobuffers(page); + ret = __set_page_dirty_nobuffers(page); + spin_unlock(req_lock); + return ret; } ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs