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	2f60ea6b8c
	
	
	
		
			
			RFC3530 states that if the client holds a delegation, then it is obliged to continue to send RENEW calls once every lease period in order to allow the server to return NFS4ERR_CB_PATH_DOWN if the callback path is unreachable. This is not required for NFSv4.1, since the server can at any time set the SEQ4_STATUS_CB_PATH_DOWN_SESSION in any SEQUENCE operation. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
		
			
				
	
	
		
			136 lines
		
	
	
	
		
			4.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			136 lines
		
	
	
	
		
			4.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  fs/nfs/nfs4renewd.c
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|  *
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|  *  Copyright (c) 2002 The Regents of the University of Michigan.
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|  *  All rights reserved.
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|  *
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|  *  Kendrick Smith <kmsmith@umich.edu>
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|  *
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|  *  Redistribution and use in source and binary forms, with or without
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|  *  modification, are permitted provided that the following conditions
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|  *  are met:
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|  *
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|  *  1. Redistributions of source code must retain the above copyright
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|  *     notice, this list of conditions and the following disclaimer.
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|  *  2. Redistributions in binary form must reproduce the above copyright
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|  *     notice, this list of conditions and the following disclaimer in the
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|  *     documentation and/or other materials provided with the distribution.
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|  *  3. Neither the name of the University nor the names of its
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|  *     contributors may be used to endorse or promote products derived
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|  *     from this software without specific prior written permission.
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|  *
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|  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
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|  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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|  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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|  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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|  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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|  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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|  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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|  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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|  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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|  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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|  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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|  *
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|  * Implementation of the NFSv4 "renew daemon", which wakes up periodically to
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|  * send a RENEW, to keep state alive on the server.  The daemon is implemented
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|  * as an rpc_task, not a real kernel thread, so it always runs in rpciod's
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|  * context.  There is one renewd per nfs_server.
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|  *
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|  */
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| 
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| #include <linux/mm.h>
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| #include <linux/pagemap.h>
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| #include <linux/sunrpc/sched.h>
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| #include <linux/sunrpc/clnt.h>
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| 
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| #include <linux/nfs.h>
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| #include <linux/nfs4.h>
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| #include <linux/nfs_fs.h>
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| #include "nfs4_fs.h"
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| #include "delegation.h"
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| 
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| #define NFSDBG_FACILITY	NFSDBG_PROC
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| 
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| void
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| nfs4_renew_state(struct work_struct *work)
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| {
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| 	const struct nfs4_state_maintenance_ops *ops;
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| 	struct nfs_client *clp =
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| 		container_of(work, struct nfs_client, cl_renewd.work);
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| 	struct rpc_cred *cred;
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| 	long lease;
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| 	unsigned long last, now;
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| 	unsigned renew_flags = 0;
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| 
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| 	ops = clp->cl_mvops->state_renewal_ops;
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| 	dprintk("%s: start\n", __func__);
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| 
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| 	if (test_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state))
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| 		goto out;
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| 
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| 	spin_lock(&clp->cl_lock);
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| 	lease = clp->cl_lease_time;
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| 	last = clp->cl_last_renewal;
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| 	now = jiffies;
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| 	/* Are we close to a lease timeout? */
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| 	if (time_after(now, last + lease/3))
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| 		renew_flags |= NFS4_RENEW_TIMEOUT;
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| 	if (nfs_delegations_present(clp))
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| 		renew_flags |= NFS4_RENEW_DELEGATION_CB;
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| 
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| 	if (renew_flags != 0) {
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| 		cred = ops->get_state_renewal_cred_locked(clp);
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| 		spin_unlock(&clp->cl_lock);
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| 		if (cred == NULL) {
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| 			if (!(renew_flags & NFS4_RENEW_DELEGATION_CB)) {
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| 				set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
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| 				goto out;
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| 			}
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| 			nfs_expire_all_delegations(clp);
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| 		} else {
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| 			/* Queue an asynchronous RENEW. */
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| 			ops->sched_state_renewal(clp, cred, renew_flags);
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| 			put_rpccred(cred);
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| 			goto out_exp;
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| 		}
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| 	} else {
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| 		dprintk("%s: failed to call renewd. Reason: lease not expired \n",
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| 				__func__);
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| 		spin_unlock(&clp->cl_lock);
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| 	}
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| 	nfs4_schedule_state_renewal(clp);
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| out_exp:
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| 	nfs_expire_unreferenced_delegations(clp);
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| out:
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| 	dprintk("%s: done\n", __func__);
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| }
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| 
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| void
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| nfs4_schedule_state_renewal(struct nfs_client *clp)
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| {
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| 	long timeout;
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| 
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| 	spin_lock(&clp->cl_lock);
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| 	timeout = (2 * clp->cl_lease_time) / 3 + (long)clp->cl_last_renewal
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| 		- (long)jiffies;
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| 	if (timeout < 5 * HZ)
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| 		timeout = 5 * HZ;
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| 	dprintk("%s: requeueing work. Lease period = %ld\n",
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| 			__func__, (timeout + HZ - 1) / HZ);
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| 	cancel_delayed_work(&clp->cl_renewd);
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| 	schedule_delayed_work(&clp->cl_renewd, timeout);
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| 	set_bit(NFS_CS_RENEWD, &clp->cl_res_state);
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| 	spin_unlock(&clp->cl_lock);
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| }
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| 
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| void
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| nfs4_kill_renewd(struct nfs_client *clp)
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| {
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| 	cancel_delayed_work_sync(&clp->cl_renewd);
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| }
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| 
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| /*
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|  * Local variables:
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|  *   c-basic-offset: 8
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|  * End:
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|  */
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