1 | /* |
2 | * fs/nfs/nfs4renewd.c |
3 | * |
4 | * Copyright (c) 2002 The Regents of the University of Michigan. |
5 | * All rights reserved. |
6 | * |
7 | * Kendrick Smith <kmsmith@umich.edu> |
8 | * |
9 | * Redistribution and use in source and binary forms, with or without |
10 | * modification, are permitted provided that the following conditions |
11 | * are met: |
12 | * |
13 | * 1. Redistributions of source code must retain the above copyright |
14 | * notice, this list of conditions and the following disclaimer. |
15 | * 2. Redistributions in binary form must reproduce the above copyright |
16 | * notice, this list of conditions and the following disclaimer in the |
17 | * documentation and/or other materials provided with the distribution. |
18 | * 3. Neither the name of the University nor the names of its |
19 | * contributors may be used to endorse or promote products derived |
20 | * from this software without specific prior written permission. |
21 | * |
22 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED |
23 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
24 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
25 | * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
26 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
27 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
28 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
29 | * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
30 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
31 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
32 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
33 | * |
34 | * Implementation of the NFSv4 "renew daemon", which wakes up periodically to |
35 | * send a RENEW, to keep state alive on the server. The daemon is implemented |
36 | * as an rpc_task, not a real kernel thread, so it always runs in rpciod's |
37 | * context. There is one renewd per nfs_server. |
38 | * |
39 | */ |
40 | |
41 | #include <linux/mm.h> |
42 | #include <linux/pagemap.h> |
43 | #include <linux/sunrpc/sched.h> |
44 | #include <linux/sunrpc/clnt.h> |
45 | |
46 | #include <linux/nfs.h> |
47 | #include <linux/nfs4.h> |
48 | #include <linux/nfs_fs.h> |
49 | #include "nfs4_fs.h" |
50 | #include "delegation.h" |
51 | |
52 | #define NFSDBG_FACILITY NFSDBG_STATE |
53 | |
54 | void |
55 | nfs4_renew_state(struct work_struct *work) |
56 | { |
57 | const struct nfs4_state_maintenance_ops *ops; |
58 | struct nfs_client *clp = |
59 | container_of(work, struct nfs_client, cl_renewd.work); |
60 | const struct cred *cred; |
61 | long lease; |
62 | unsigned long last, now; |
63 | unsigned renew_flags = 0; |
64 | |
65 | ops = clp->cl_mvops->state_renewal_ops; |
66 | dprintk("%s: start\n" , __func__); |
67 | |
68 | if (test_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state)) |
69 | goto out; |
70 | |
71 | lease = clp->cl_lease_time; |
72 | last = clp->cl_last_renewal; |
73 | now = jiffies; |
74 | /* Are we close to a lease timeout? */ |
75 | if (time_after(now, last + lease/3)) |
76 | renew_flags |= NFS4_RENEW_TIMEOUT; |
77 | if (nfs_delegations_present(clp)) |
78 | renew_flags |= NFS4_RENEW_DELEGATION_CB; |
79 | |
80 | if (renew_flags != 0) { |
81 | cred = ops->get_state_renewal_cred(clp); |
82 | if (cred == NULL) { |
83 | if (!(renew_flags & NFS4_RENEW_DELEGATION_CB)) { |
84 | set_bit(nr: NFS4CLNT_LEASE_EXPIRED, addr: &clp->cl_state); |
85 | goto out; |
86 | } |
87 | nfs_expire_all_delegations(clp); |
88 | } else { |
89 | int ret; |
90 | |
91 | /* Queue an asynchronous RENEW. */ |
92 | ret = ops->sched_state_renewal(clp, cred, renew_flags); |
93 | put_cred(cred); |
94 | switch (ret) { |
95 | default: |
96 | goto out_exp; |
97 | case -EAGAIN: |
98 | case -ENOMEM: |
99 | break; |
100 | } |
101 | } |
102 | } else { |
103 | dprintk("%s: failed to call renewd. Reason: lease not expired \n" , |
104 | __func__); |
105 | } |
106 | nfs4_schedule_state_renewal(clp); |
107 | out_exp: |
108 | nfs_expire_unreferenced_delegations(clp); |
109 | out: |
110 | dprintk("%s: done\n" , __func__); |
111 | } |
112 | |
113 | void |
114 | nfs4_schedule_state_renewal(struct nfs_client *clp) |
115 | { |
116 | long timeout; |
117 | |
118 | spin_lock(lock: &clp->cl_lock); |
119 | timeout = (2 * clp->cl_lease_time) / 3 + (long)clp->cl_last_renewal |
120 | - (long)jiffies; |
121 | if (timeout < 5 * HZ) |
122 | timeout = 5 * HZ; |
123 | dprintk("%s: requeueing work. Lease period = %ld\n" , |
124 | __func__, (timeout + HZ - 1) / HZ); |
125 | mod_delayed_work(wq: system_wq, dwork: &clp->cl_renewd, delay: timeout); |
126 | set_bit(NFS_CS_RENEWD, addr: &clp->cl_res_state); |
127 | spin_unlock(lock: &clp->cl_lock); |
128 | } |
129 | |
130 | void |
131 | nfs4_kill_renewd(struct nfs_client *clp) |
132 | { |
133 | cancel_delayed_work_sync(dwork: &clp->cl_renewd); |
134 | } |
135 | |
136 | /** |
137 | * nfs4_set_lease_period - Sets the lease period on a nfs_client |
138 | * |
139 | * @clp: pointer to nfs_client |
140 | * @lease: new value for lease period |
141 | */ |
142 | void nfs4_set_lease_period(struct nfs_client *clp, |
143 | unsigned long lease) |
144 | { |
145 | spin_lock(lock: &clp->cl_lock); |
146 | clp->cl_lease_time = lease; |
147 | spin_unlock(lock: &clp->cl_lock); |
148 | |
149 | /* Cap maximum reconnect timeout at 1/2 lease period */ |
150 | rpc_set_connect_timeout(clnt: clp->cl_rpcclient, connect_timeout: lease, reconnect_timeout: lease >> 1); |
151 | } |
152 | |