nfsd4: don't sleep in lease-break callback
[safe/jmp/linux-2.6] / fs / nfsd / nfs4state.c
index c97fddb..adc51d1 100644 (file)
@@ -44,8 +44,8 @@
 #define NFSDDBG_FACILITY                NFSDDBG_PROC
 
 /* Globals */
-static time_t lease_time = 90;     /* default lease time */
-static time_t user_lease_time = 90;
+time_t nfsd4_lease = 90;     /* default lease time */
+time_t nfsd4_grace = 90;
 static time_t boot_time;
 static u32 current_ownerid = 1;
 static u32 current_fileid = 1;
@@ -198,6 +198,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_stateid *stp, struct svc_f
        atomic_set(&dp->dl_count, 1);
        list_add(&dp->dl_perfile, &fp->fi_delegations);
        list_add(&dp->dl_perclnt, &clp->cl_delegations);
+       INIT_WORK(&dp->dl_recall.cb_work, nfsd4_do_callback_rpc);
        return dp;
 }
 
@@ -679,27 +680,9 @@ static struct nfs4_client *alloc_client(struct xdr_netobj name)
        return clp;
 }
 
-static void
-shutdown_callback_client(struct nfs4_client *clp)
-{
-       struct rpc_clnt *clnt = clp->cl_cb_conn.cb_client;
-
-       if (clnt) {
-               /*
-                * Callback threads take a reference on the client, so there
-                * should be no outstanding callbacks at this point.
-                */
-               clp->cl_cb_conn.cb_client = NULL;
-               rpc_shutdown_client(clnt);
-       }
-}
-
 static inline void
 free_client(struct nfs4_client *clp)
 {
-       shutdown_callback_client(clp);
-       if (clp->cl_cb_xprt)
-               svc_xprt_put(clp->cl_cb_xprt);
        if (clp->cl_cred.cr_group_info)
                put_group_info(clp->cl_cred.cr_group_info);
        kfree(clp->cl_principal);
@@ -721,9 +704,6 @@ expire_client(struct nfs4_client *clp)
        struct nfs4_delegation *dp;
        struct list_head reaplist;
 
-       dprintk("NFSD: expire_client cl_count %d\n",
-                           atomic_read(&clp->cl_count));
-
        INIT_LIST_HEAD(&reaplist);
        spin_lock(&recall_lock);
        while (!list_empty(&clp->cl_delegations)) {
@@ -752,6 +732,9 @@ expire_client(struct nfs4_client *clp)
                                 se_perclnt);
                release_session(ses);
        }
+       nfsd4_set_callback_client(clp, NULL);
+       if (clp->cl_cb_xprt)
+               svc_xprt_put(clp->cl_cb_xprt);
        put_nfs4_client(clp);
 }
 
@@ -1326,12 +1309,6 @@ nfsd4_create_session(struct svc_rqst *rqstp,
                cs_slot->sl_seqid++; /* from 0 to 1 */
                move_to_confirmed(unconf);
 
-               /*
-                * We do not support RDMA or persistent sessions
-                */
-               cr_ses->flags &= ~SESSION4_PERSIST;
-               cr_ses->flags &= ~SESSION4_RDMA;
-
                if (cr_ses->flags & SESSION4_BACK_CHAN) {
                        unconf->cl_cb_xprt = rqstp->rq_xprt;
                        svc_xprt_get(unconf->cl_cb_xprt);
@@ -1351,6 +1328,12 @@ nfsd4_create_session(struct svc_rqst *rqstp,
                goto out;
        }
 
+       /*
+        * We do not support RDMA or persistent sessions
+        */
+       cr_ses->flags &= ~SESSION4_PERSIST;
+       cr_ses->flags &= ~SESSION4_RDMA;
+
        status = alloc_init_session(rqstp, conf, cr_ses);
        if (status)
                goto out;
@@ -1395,7 +1378,7 @@ nfsd4_destroy_session(struct svc_rqst *r,
        spin_unlock(&sessionid_lock);
 
        /* wait for callbacks */
-       shutdown_callback_client(ses->se_client);
+       nfsd4_set_callback_client(ses->se_client, NULL);
        nfsd4_put_session(ses);
        status = nfs_ok;
 out:
@@ -2553,6 +2536,12 @@ nfsd4_end_grace(void)
        dprintk("NFSD: end of grace period\n");
        nfsd4_recdir_purge_old();
        locks_end_grace(&nfsd4_manager);
+       /*
+        * Now that every NFSv4 client has had the chance to recover and
+        * to see the (possibly new, possibly shorter) lease time, we
+        * can safely set the next grace time to the current lease time:
+        */
+       nfsd4_grace = nfsd4_lease;
 }
 
 static time_t
@@ -2562,9 +2551,9 @@ nfs4_laundromat(void)
        struct nfs4_stateowner *sop;
        struct nfs4_delegation *dp;
        struct list_head *pos, *next, reaplist;
-       time_t cutoff = get_seconds() - NFSD_LEASE_TIME;
-       time_t t, clientid_val = NFSD_LEASE_TIME;
-       time_t u, test_val = NFSD_LEASE_TIME;
+       time_t cutoff = get_seconds() - nfsd4_lease;
+       time_t t, clientid_val = nfsd4_lease;
+       time_t u, test_val = nfsd4_lease;
 
        nfs4_lock_state();
 
@@ -2604,7 +2593,7 @@ nfs4_laundromat(void)
                list_del_init(&dp->dl_recall_lru);
                unhash_delegation(dp);
        }
-       test_val = NFSD_LEASE_TIME;
+       test_val = nfsd4_lease;
        list_for_each_safe(pos, next, &close_lru) {
                sop = list_entry(pos, struct nfs4_stateowner, so_close_lru);
                if (time_after((unsigned long)sop->so_time, (unsigned long)cutoff)) {
@@ -2674,7 +2663,7 @@ EXPIRED_STATEID(stateid_t *stateid)
 {
        if (time_before((unsigned long)boot_time,
                        ((unsigned long)stateid->si_boot)) &&
-           time_before((unsigned long)(stateid->si_boot + lease_time), get_seconds())) {
+           time_before((unsigned long)(stateid->si_boot + nfsd4_lease), get_seconds())) {
                dprintk("NFSD: expired stateid " STATEID_FMT "!\n",
                        STATEID_VAL(stateid));
                return 1;
@@ -3975,12 +3964,6 @@ nfsd4_load_reboot_recovery_data(void)
                printk("NFSD: Failure reading reboot recovery data\n");
 }
 
-unsigned long
-get_nfs4_grace_period(void)
-{
-       return max(user_lease_time, lease_time) * HZ;
-}
-
 /*
  * Since the lifetime of a delegation isn't limited to that of an open, a
  * client may quite reasonably hang on to a delegation as long as it has
@@ -4007,20 +3990,27 @@ set_max_delegations(void)
 static int
 __nfs4_state_start(void)
 {
-       unsigned long grace_time;
+       int ret;
 
        boot_time = get_seconds();
-       grace_time = get_nfs4_grace_period();
-       lease_time = user_lease_time;
        locks_start_grace(&nfsd4_manager);
        printk(KERN_INFO "NFSD: starting %ld-second grace period\n",
-              grace_time/HZ);
+              nfsd4_grace);
+       ret = set_callback_cred();
+       if (ret)
+               return -ENOMEM;
        laundry_wq = create_singlethread_workqueue("nfsd4");
        if (laundry_wq == NULL)
                return -ENOMEM;
-       queue_delayed_work(laundry_wq, &laundromat_work, grace_time);
+       ret = nfsd4_create_callback_queue();
+       if (ret)
+               goto out_free_laundry;
+       queue_delayed_work(laundry_wq, &laundromat_work, nfsd4_grace * HZ);
        set_max_delegations();
-       return set_callback_cred();
+       return 0;
+out_free_laundry:
+       destroy_workqueue(laundry_wq);
+       return ret;
 }
 
 int
@@ -4038,12 +4028,6 @@ nfs4_state_start(void)
        return 0;
 }
 
-time_t
-nfs4_lease_time(void)
-{
-       return lease_time;
-}
-
 static void
 __nfs4_state_shutdown(void)
 {
@@ -4088,6 +4072,7 @@ nfs4_state_shutdown(void)
        nfs4_lock_state();
        nfs4_release_reclaim();
        __nfs4_state_shutdown();
+       nfsd4_destroy_callback_queue();
        nfs4_unlock_state();
 }
 
@@ -4127,21 +4112,3 @@ nfs4_recoverydir(void)
 {
        return user_recovery_dirname;
 }
-
-/*
- * Called when leasetime is changed.
- *
- * The only way the protocol gives us to handle on-the-fly lease changes is to
- * simulate a reboot.  Instead of doing that, we just wait till the next time
- * we start to register any changes in lease time.  If the administrator
- * really wants to change the lease time *now*, they can go ahead and bring
- * nfsd down and then back up again after changing the lease time.
- *
- * user_lease_time is protected by nfsd_mutex since it's only really accessed
- * when nfsd is starting
- */
-void
-nfs4_reset_lease(time_t leasetime)
-{
-       user_lease_time = leasetime;
-}