diff options
Diffstat (limited to 'fs/nfs/nfs4renewd.c')
| -rw-r--r-- | fs/nfs/nfs4renewd.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c new file mode 100644 index 000000000..ff876dda7 --- /dev/null +++ b/fs/nfs/nfs4renewd.c @@ -0,0 +1,157 @@ +/* + * fs/nfs/nfs4renewd.c + * + * Copyright (c) 2002 The Regents of the University of Michigan. + * All rights reserved. + * + * Kendrick Smith <kmsmith@umich.edu> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Implementation of the NFSv4 "renew daemon", which wakes up periodically to + * send a RENEW, to keep state alive on the server. The daemon is implemented + * as an rpc_task, not a real kernel thread, so it always runs in rpciod's + * context. There is one renewd per nfs_server. + * + */ + +#include <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/sunrpc/sched.h> +#include <linux/sunrpc/clnt.h> + +#include <linux/nfs.h> +#include <linux/nfs4.h> +#include <linux/nfs_fs.h> +#include "nfs4_fs.h" +#include "delegation.h" + +#define NFSDBG_FACILITY NFSDBG_STATE + +void +nfs4_renew_state(struct work_struct *work) +{ + const struct nfs4_state_maintenance_ops *ops; + struct nfs_client *clp = + container_of(work, struct nfs_client, cl_renewd.work); + const struct cred *cred; + long lease; + unsigned long last, now; + unsigned renew_flags = 0; + + ops = clp->cl_mvops->state_renewal_ops; + dprintk("%s: start\n", __func__); + + if (test_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state)) + goto out; + + lease = clp->cl_lease_time; + last = clp->cl_last_renewal; + now = jiffies; + /* Are we close to a lease timeout? */ + if (time_after(now, last + lease/3)) + renew_flags |= NFS4_RENEW_TIMEOUT; + if (nfs_delegations_present(clp)) + renew_flags |= NFS4_RENEW_DELEGATION_CB; + + if (renew_flags != 0) { + cred = ops->get_state_renewal_cred(clp); + if (cred == NULL) { + if (!(renew_flags & NFS4_RENEW_DELEGATION_CB)) { + set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); + goto out; + } + nfs_expire_all_delegations(clp); + } else { + int ret; + + /* Queue an asynchronous RENEW. */ + ret = ops->sched_state_renewal(clp, cred, renew_flags); + put_cred(cred); + switch (ret) { + default: + goto out_exp; + case -EAGAIN: + case -ENOMEM: + break; + } + } + } else { + dprintk("%s: failed to call renewd. Reason: lease not expired \n", + __func__); + } + nfs4_schedule_state_renewal(clp); +out_exp: + nfs_expire_unreferenced_delegations(clp); +out: + dprintk("%s: done\n", __func__); +} + +void +nfs4_schedule_state_renewal(struct nfs_client *clp) +{ + long timeout; + + spin_lock(&clp->cl_lock); + timeout = (2 * clp->cl_lease_time) / 3 + (long)clp->cl_last_renewal + - (long)jiffies; + if (timeout < 5 * HZ) + timeout = 5 * HZ; + dprintk("%s: requeueing work. Lease period = %ld\n", + __func__, (timeout + HZ - 1) / HZ); + mod_delayed_work(system_wq, &clp->cl_renewd, timeout); + set_bit(NFS_CS_RENEWD, &clp->cl_res_state); + spin_unlock(&clp->cl_lock); +} + +void +nfs4_kill_renewd(struct nfs_client *clp) +{ + cancel_delayed_work_sync(&clp->cl_renewd); +} + +/** + * nfs4_set_lease_period - Sets the lease period on a nfs_client + * + * @clp: pointer to nfs_client + * @lease: new value for lease period + */ +void nfs4_set_lease_period(struct nfs_client *clp, + unsigned long lease) +{ + spin_lock(&clp->cl_lock); + clp->cl_lease_time = lease; + spin_unlock(&clp->cl_lock); + + /* Cap maximum reconnect timeout at 1/2 lease period */ + rpc_set_connect_timeout(clp->cl_rpcclient, lease, lease >> 1); +} + +/* + * Local variables: + * c-basic-offset: 8 + * End: + */ |