On Mon, Mar 23, 2015 at 10:09 AM, Trond Myklebust
<trond.myklebust@xxxxxxxxxxxxxxx> wrote:
> 8<---------------------------------------------------------------
> From 21fb62639ad69ecc5c443dba5b41ad2bd64c6e76 Mon Sep 17 00:00:00 2001
> From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> Date: Mon, 23 Mar 2015 09:51:41 -0400
> Subject: [PATCH] NFSv4: Ensure that we drain the session before shutting it
> down
>
> Kinglong Mee reports that the call to DESTROY_SESSION in NFSv4.1
> are racing with the asynchronous DELEGRETURN calls that precede it.
> This points to the root cause being that we're not waiting for the
> session to drain before we destroy it.
>
> This patch ensures that we do so for both NFSv4 and NFSv4.1.
>
> Reported-by: Kinglong Mee <kinglongmee@xxxxxxxxx>
> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> ---
> fs/nfs/nfs4_fs.h | 3 +++
> fs/nfs/nfs4client.c | 7 ++-----
> fs/nfs/nfs4state.c | 18 ++++++++++++++++++
> 3 files changed, 23 insertions(+), 5 deletions(-)
>
> diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
> index fdef424b0cd3..594f53c3aee5 100644
> --- a/fs/nfs/nfs4_fs.h
> +++ b/fs/nfs/nfs4_fs.h
> @@ -257,6 +257,8 @@ extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
> const struct nfs_lock_context *l_ctx,
> fmode_t fmode);
>
> +extern void nfs40_shutdown_session(struct nfs_client *clp);
> +
> #if defined(CONFIG_NFS_V4_1)
> static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
> {
> @@ -269,6 +271,7 @@ extern int nfs41_setup_sequence(struct nfs4_session *session,
> extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
> extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
> extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
> +extern void nfs41_shutdown_session(struct nfs_client *clp, struct nfs4_session *session);
> extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
> struct nfs_fsinfo *fsinfo);
> extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
> diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
> index 86d6214ea022..bdabbf9b6322 100644
> --- a/fs/nfs/nfs4client.c
> +++ b/fs/nfs/nfs4client.c
> @@ -160,7 +160,7 @@ void nfs41_shutdown_client(struct nfs_client *clp)
> {
> if (nfs4_has_session(clp)) {
> nfs4_shutdown_ds_clients(clp);
> - nfs4_destroy_session(clp->cl_session);
> + nfs41_shutdown_session(clp, clp->cl_session);
> nfs4_destroy_clientid(clp);
> }
>
> @@ -169,10 +169,7 @@ void nfs41_shutdown_client(struct nfs_client *clp)
>
> void nfs40_shutdown_client(struct nfs_client *clp)
> {
> - if (clp->cl_slot_tbl) {
> - nfs4_shutdown_slot_table(clp->cl_slot_tbl);
> - kfree(clp->cl_slot_tbl);
> - }
> + nfs40_shutdown_session(clp);
> }
>
> struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
> diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
> index f95e3b58bbc3..54fa7e2bc3e3 100644
> --- a/fs/nfs/nfs4state.c
> +++ b/fs/nfs/nfs4state.c
> @@ -2134,6 +2134,18 @@ out_unlock:
> return status;
> }
>
> +void nfs40_shutdown_session(struct nfs_client *clp)
> +{
> + struct nfs4_slot_table *tbl = clp->cl_slot_tbl;
> +
> + if (tbl) {
> + nfs4_drain_slot_tbl(tbl);
> + nfs4_shutdown_slot_table(tbl);
> + clp->cl_slot_tbl = NULL;
> + kfree(tbl);
> + }
> +}
> +
> #ifdef CONFIG_NFS_V4_1
> void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
> {
> @@ -2314,6 +2326,12 @@ static int nfs4_bind_conn_to_session(struct nfs_client *clp)
> }
> return 0;
> }
> +
> +void nfs41_shutdown_session(struct nfs_client *clp, struct nfs4_session *session)
> +{
> + nfs4_begin_drain_session(clp);
Argh. We can't quite do this, because we do want all outstanding RPC
calls to complete, not just the ones that have already been allocated
slots. Let me respin.
> + nfs4_destroy_session(session);
> +}
> #else /* CONFIG_NFS_V4_1 */
> static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
>
> --
> 2.1.0
>
>
>
>
--
Trond Myklebust
Linux NFS client maintainer, PrimaryData
trond.myklebust@xxxxxxxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
