blob: 5e2e4af1a0e6c016237448b8e810165da63190d3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 * TODO: If the send queue gets backlogged (e.g., if the server goes down),
40 * we will keep filling the queue with periodic RENEW requests. We need a
41 * mechanism for ensuring that if renewd successfully sends off a request,
42 * then it only wakes up when the request is finished. Maybe use the
43 * child task framework of the RPC layer?
44 */
45
Linus Torvalds1da177e2005-04-16 15:20:36 -070046#include <linux/mm.h>
47#include <linux/pagemap.h>
48#include <linux/sunrpc/sched.h>
49#include <linux/sunrpc/clnt.h>
50
51#include <linux/nfs.h>
52#include <linux/nfs4.h>
53#include <linux/nfs_fs.h>
Trond Myklebust4ce79712005-06-22 17:16:21 +000054#include "nfs4_fs.h"
Trond Myklebust58d9714a2006-01-03 09:55:24 +010055#include "delegation.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57#define NFSDBG_FACILITY NFSDBG_PROC
58
59void
David Howells65f27f32006-11-22 14:55:48 +000060nfs4_renew_state(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -070061{
David Howells65f27f32006-11-22 14:55:48 +000062 struct nfs_client *clp =
63 container_of(work, struct nfs_client, cl_renewd.work);
Trond Myklebustb4454fe2006-01-03 09:55:25 +010064 struct rpc_cred *cred;
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 long lease, timeout;
66 unsigned long last, now;
67
68 down_read(&clp->cl_sem);
69 dprintk("%s: start\n", __FUNCTION__);
70 /* Are there any active superblocks? */
71 if (list_empty(&clp->cl_superblocks))
Trond Myklebust58d9714a2006-01-03 09:55:24 +010072 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 spin_lock(&clp->cl_lock);
74 lease = clp->cl_lease_time;
75 last = clp->cl_last_renewal;
76 now = jiffies;
77 timeout = (2 * lease) / 3 + (long)last - (long)now;
78 /* Are we close to a lease timeout? */
79 if (time_after(now, last + lease/3)) {
Trond Myklebustb4454fe2006-01-03 09:55:25 +010080 cred = nfs4_get_renew_cred(clp);
81 if (cred == NULL) {
Trond Myklebust58d9714a2006-01-03 09:55:24 +010082 set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
83 spin_unlock(&clp->cl_lock);
84 nfs_expire_all_delegations(clp);
85 goto out;
86 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 spin_unlock(&clp->cl_lock);
88 /* Queue an asynchronous RENEW. */
Trond Myklebustb4454fe2006-01-03 09:55:25 +010089 nfs4_proc_async_renew(clp, cred);
90 put_rpccred(cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 timeout = (2 * lease) / 3;
92 spin_lock(&clp->cl_lock);
93 } else
94 dprintk("%s: failed to call renewd. Reason: lease not expired \n",
95 __FUNCTION__);
96 if (timeout < 5 * HZ) /* safeguard */
97 timeout = 5 * HZ;
98 dprintk("%s: requeueing work. Lease period = %ld\n",
99 __FUNCTION__, (timeout + HZ - 1) / HZ);
100 cancel_delayed_work(&clp->cl_renewd);
101 schedule_delayed_work(&clp->cl_renewd, timeout);
102 spin_unlock(&clp->cl_lock);
103out:
104 up_read(&clp->cl_sem);
105 dprintk("%s: done\n", __FUNCTION__);
106}
107
108/* Must be called with clp->cl_sem locked for writes */
109void
David Howellsadfa6f92006-08-22 20:06:08 -0400110nfs4_schedule_state_renewal(struct nfs_client *clp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111{
112 long timeout;
113
114 spin_lock(&clp->cl_lock);
115 timeout = (2 * clp->cl_lease_time) / 3 + (long)clp->cl_last_renewal
116 - (long)jiffies;
117 if (timeout < 5 * HZ)
118 timeout = 5 * HZ;
119 dprintk("%s: requeueing work. Lease period = %ld\n",
120 __FUNCTION__, (timeout + HZ - 1) / HZ);
121 cancel_delayed_work(&clp->cl_renewd);
122 schedule_delayed_work(&clp->cl_renewd, timeout);
Trond Myklebust5dd31772006-08-24 01:03:05 -0400123 set_bit(NFS_CS_RENEWD, &clp->cl_res_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 spin_unlock(&clp->cl_lock);
125}
126
127void
128nfs4_renewd_prepare_shutdown(struct nfs_server *server)
129{
Trond Myklebust3d39c692007-08-07 15:28:33 -0400130 cancel_delayed_work(&server->nfs_client->cl_renewd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131}
132
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133void
David Howellsadfa6f92006-08-22 20:06:08 -0400134nfs4_kill_renewd(struct nfs_client *clp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135{
Trond Myklebust3d39c692007-08-07 15:28:33 -0400136 cancel_delayed_work_sync(&clp->cl_renewd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137}
138
139/*
140 * Local variables:
141 * c-basic-offset: 8
142 * End:
143 */