Return-Path: Received: from daytona.panasas.com ([67.152.220.89]:40093 "EHLO daytona.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751768Ab1EVSJI (ORCPT ); Sun, 22 May 2011 14:09:08 -0400 Message-ID: <4DD9513B.9070003@panasas.com> Date: Sun, 22 May 2011 21:08:59 +0300 From: Benny Halevy To: Boaz Harrosh CC: Trond Myklebust , NFS list Subject: Re: [PATCH 10/13] [RFC] Bugs in new pnfs write path References: <4DD79273.9030202@panasas.com> <1305973982-17499-1-git-send-email-bharrosh@panasas.com> In-Reply-To: <1305973982-17499-1-git-send-email-bharrosh@panasas.com> Content-Type: text/plain; charset=windows-1255 Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On 2011-05-21 13:33, Boaz Harrosh wrote: > 1. In nfs4_write_done_cb: data->write_done_cb comes with a NULL. what's the call path? > Just as a guess I call nfs4_write_done_cb() just above it > it looked like the right thing todo. With that in, I'm able > to write things to file When converting pnfs.c:258 to a WARN_ON. > > Benny we might want to set data->write_done_cb somewhere in the > none-rpc path? where is it best to do that? we're not supposed to get there in the non-rpc path... The non-rpc drivers must call pnfs_ld_write_done. > > 2. In pnfs_ld_write_done: > put_lseg(data->lseg); > data->lseg = NULL; > was done before the call to pnfs_set_layoutcommit() > which trys to get_lseg() on that same data->lseg. good catch, thanks! > > 3. In pnfs_ld_write_done: > data->mds_ops->rpc_call_done(NULL, data); > crashes with a NULL task. Just pass it with &data->task As we don't go through nfs_initiate_write data->task is not initialized. Where's the crash exactly? We better fix it than fake a task structure... Benny > > Which calls for a cleanup. There is bunch of functions > with [task, write_data] API. And the task is always > write_data->task > > Signed-off-by: Boaz Harrosh > --- > fs/nfs/nfs4proc.c | 3 ++- > fs/nfs/pnfs.c | 10 ++++++---- > 2 files changed, 8 insertions(+), 5 deletions(-) > > diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c > index 759523a..1a53187 100644 > --- a/fs/nfs/nfs4proc.c > +++ b/fs/nfs/nfs4proc.c > @@ -3250,7 +3250,8 @@ static int nfs4_write_done(struct rpc_task *task, struct nfs_write_data *data) > { > if (!nfs4_sequence_done(task, &data->res.seq_res)) > return -EAGAIN; > - return data->write_done_cb(task, data); > + return data->write_done_cb ? data->write_done_cb(task, data) : > + nfs4_write_done_cb(task, data); > } > > /* Reset the the nfs_write_data to send the write to the MDS. */ > diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c > index 17d0c4c..b04cdb4 100644 > --- a/fs/nfs/pnfs.c > +++ b/fs/nfs/pnfs.c > @@ -255,7 +255,7 @@ put_lseg_common(struct pnfs_layout_segment *lseg) > { > struct inode *inode = lseg->pls_layout->plh_inode; > > - BUG_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags)); > + WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags)); > list_del_init(&lseg->pls_list); > if (list_empty(&lseg->pls_layout->plh_segs)) { > set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags); > @@ -1124,15 +1124,17 @@ pnfs_ld_write_done(struct nfs_write_data *data) > { > int status; > > - put_lseg(data->lseg); > - data->lseg = NULL; > if (!data->pnfs_error) { > pnfs_set_layoutcommit(data); > - data->mds_ops->rpc_call_done(NULL, data); > + data->mds_ops->rpc_call_done(&data->task, data); > data->mds_ops->rpc_release(data); > + put_lseg(data->lseg); > + data->lseg = NULL; > return 0; > } > > + put_lseg(data->lseg); > + data->lseg = NULL; > dprintk("%s: pnfs_error=%d, retry via MDS\n", __func__, > data->pnfs_error); > status = nfs_initiate_write(data, NFS_CLIENT(data->inode), data->mds_ops, NFS_FILE_SYNC);