From patchwork Mon Jul 18 15:26:30 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 987042 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.4) with ESMTP id p6IFQbmV029738 for ; Mon, 18 Jul 2011 15:26:37 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752754Ab1GRP0f (ORCPT ); Mon, 18 Jul 2011 11:26:35 -0400 Received: from mail-yi0-f46.google.com ([209.85.218.46]:39145 "EHLO mail-yi0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751808Ab1GRP0e (ORCPT ); Mon, 18 Jul 2011 11:26:34 -0400 Received: by yia27 with SMTP id 27so1343843yia.19 for ; Mon, 18 Jul 2011 08:26:34 -0700 (PDT) Received: by 10.101.192.29 with SMTP id u29mr5623713anp.66.1311002793970; Mon, 18 Jul 2011 08:26:33 -0700 (PDT) Received: from salusa.poochiereds.net (cpe-076-182-054-018.nc.res.rr.com [76.182.54.18]) by mx.google.com with ESMTPS id i33sm4544899anm.24.2011.07.18.08.26.32 (version=SSLv3 cipher=OTHER); Mon, 18 Jul 2011 08:26:33 -0700 (PDT) From: Jeff Layton To: Trond.Myklebust@netapp.com Cc: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, viro@ZenIV.linux.org.uk Subject: [PATCH] nfs: don't use d_move in nfs_async_rename_done Date: Mon, 18 Jul 2011 11:26:30 -0400 Message-Id: <1311002790-6650-1-git-send-email-jlayton@redhat.com> X-Mailer: git-send-email 1.7.6 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Mon, 18 Jul 2011 15:26:37 +0000 (UTC) If the task that initiated the sillyrename ends up being killed by a fatal signal, then it will eventually return back to userspace and end up releasing the i_mutex. d_move however needs to be done while holding the i_mutex. Instead of using d_move here, just unhash the old and new dentries to prevent them from being found by lookups. With this change though, the dentries are now incorrect post-rename and do not reflect the actual name of the file on the server. I'm proceeding under the assumption that since they are unhashed that this isn't really a problem. In order for the sillydelete to still work though, the dname must be copied earlier when setting up the sillydelete info, and the name must be recopied if the sillydelete info has to be moved to a new dentry. Reported-by: Al Viro Signed-off-by: Jeff Layton --- fs/nfs/unlink.c | 29 +++++++++++++++++++---------- 1 files changed, 19 insertions(+), 10 deletions(-) diff --git a/fs/nfs/unlink.c b/fs/nfs/unlink.c index 8d6864c..7687f4f 100644 --- a/fs/nfs/unlink.c +++ b/fs/nfs/unlink.c @@ -147,7 +147,7 @@ static int nfs_do_call_unlink(struct dentry *parent, struct inode *dir, struct n alias = d_lookup(parent, &data->args.name); if (alias != NULL) { - int ret = 0; + int ret; void *devname_garbage = NULL; /* @@ -155,14 +155,16 @@ static int nfs_do_call_unlink(struct dentry *parent, struct inode *dir, struct n * the sillyrename information to the aliased dentry. */ nfs_free_dname(data); + ret = nfs_copy_dname(alias, data); spin_lock(&alias->d_lock); - if (alias->d_inode != NULL && + if (ret == 0 && alias->d_inode != NULL && !(alias->d_flags & DCACHE_NFSFS_RENAMED)) { devname_garbage = alias->d_fsdata; alias->d_fsdata = data; alias->d_flags |= DCACHE_NFSFS_RENAMED; ret = 1; - } + } else + ret = 0; spin_unlock(&alias->d_lock); nfs_dec_sillycount(dir); dput(alias); @@ -171,8 +173,7 @@ static int nfs_do_call_unlink(struct dentry *parent, struct inode *dir, struct n * point dentry is definitely not a root, so we won't need * that anymore. */ - if (devname_garbage) - kfree(devname_garbage); + kfree(devname_garbage); return ret; } data->dir = igrab(dir); @@ -204,8 +205,6 @@ static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data) if (parent == NULL) goto out_free; dir = parent->d_inode; - if (nfs_copy_dname(dentry, data) != 0) - goto out_dput; /* Non-exclusive lock protects against concurrent lookup() calls */ spin_lock(&dir->i_lock); if (atomic_inc_not_zero(&NFS_I(dir)->silly_count) == 0) { @@ -366,6 +365,8 @@ static void nfs_async_rename_done(struct rpc_task *task, void *calldata) struct nfs_renamedata *data = calldata; struct inode *old_dir = data->old_dir; struct inode *new_dir = data->new_dir; + struct dentry *old_dentry = data->old_dentry; + struct dentry *new_dentry = data->new_dentry; if (!NFS_PROTO(old_dir)->rename_done(task, old_dir, new_dir)) { nfs_restart_rpc(task, NFS_SERVER(old_dir)->nfs_client); @@ -373,12 +374,12 @@ static void nfs_async_rename_done(struct rpc_task *task, void *calldata) } if (task->tk_status != 0) { - nfs_cancel_async_unlink(data->old_dentry); + nfs_cancel_async_unlink(old_dentry); return; } - nfs_set_verifier(data->old_dentry, nfs_save_change_attribute(old_dir)); - d_move(data->old_dentry, data->new_dentry); + d_drop(old_dentry); + d_drop(new_dentry); } /** @@ -560,6 +561,14 @@ nfs_sillyrename(struct inode *dir, struct dentry *dentry) if (error) goto out_dput; + /* populate unlinkdata with the right dname */ + error = nfs_copy_dname(sdentry, + (struct nfs_unlinkdata *)dentry->d_fsdata); + if (error) { + nfs_cancel_async_unlink(dentry); + goto out_dput; + } + /* run the rename task, undo unlink if it fails */ task = nfs_async_rename(dir, dir, dentry, sdentry); if (IS_ERR(task)) {