nfs4state.c

/*
 *  fs/nfs/nfs4state.c
 *
 *  Client-side XDR for NFSv4.
 *
 *  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 state model.  For the time being,
 * this is minimal, but will be made much more complex in a
 * subsequent patch.
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_idmap.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/ratelimit.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>

#include <linux/sunrpc/clnt.h>

#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "internal.h"
#include "nfs4session.h"
#include "pnfs.h"
#include "netns.h"

#define NFSDBG_FACILITY		NFSDBG_STATE

#define OPENOWNER_POOL_SIZE	8

const nfs4_stateid zero_stateid;
static DEFINE_MUTEX(nfs_clid_init_mutex);

int nfs4_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
{
	struct nfs4_setclientid_res clid = {
		.clientid = clp->cl_clientid,
		.confirm = clp->cl_confirm,
	};
	unsigned short port;
	int status;
	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);

	if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
		goto do_confirm;
	port = nn->nfs_callback_tcpport;
	if (clp->cl_addr.ss_family == AF_INET6)
		port = nn->nfs_callback_tcpport6;

	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
	if (status != 0)
		goto out;
	clp->cl_clientid = clid.clientid;
	clp->cl_confirm = clid.confirm;
	set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
do_confirm:
	status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
	if (status != 0)
		goto out;
	clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
	nfs4_schedule_state_renewal(clp);
out:
	return status;
}

/**
 * nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
 *
 * @clp: nfs_client under test
 * @result: OUT: found nfs_client, or clp
 * @cred: credential to use for trunking test
 *
 * Returns zero, a negative errno, or a negative NFS4ERR status.
 * If zero is returned, an nfs_client pointer is planted in
 * "result".
 *
 * Note: The returned client may not yet be marked ready.
 */
int nfs40_discover_server_trunking(struct nfs_client *clp,
				   struct nfs_client **result,
				   struct rpc_cred *cred)
{
	struct nfs4_setclientid_res clid = {
		.clientid = clp->cl_clientid,
		.confirm = clp->cl_confirm,
	};
	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
	unsigned short port;
	int status;

	port = nn->nfs_callback_tcpport;
	if (clp->cl_addr.ss_family == AF_INET6)
		port = nn->nfs_callback_tcpport6;

	status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
	if (status != 0)
		goto out;
	clp->cl_clientid = clid.clientid;
	clp->cl_confirm = clid.confirm;

	status = nfs40_walk_client_list(clp, result, cred);
	if (status == 0) {
		/* Sustain the lease, even if it's empty.  If the clientid4
		 * goes stale it's of no use for trunking discovery. */
		nfs4_schedule_state_renewal(*result);
	}
out:
	return status;
}

struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
{
	struct rpc_cred *cred = NULL;

	if (clp->cl_machine_cred != NULL)
		cred = get_rpccred(clp->cl_machine_cred);
	return cred;
}

static void nfs4_root_machine_cred(struct nfs_client *clp)
{
	struct rpc_cred *cred, *new;

	new = rpc_lookup_machine_cred(NULL);
	spin_lock(&clp->cl_lock);
	cred = clp->cl_machine_cred;
	clp->cl_machine_cred = new;
	spin_unlock(&clp->cl_lock);
	if (cred != NULL)
		put_rpccred(cred);
}

static struct rpc_cred *
nfs4_get_renew_cred_server_locked(struct nfs_server *server)
{
	struct rpc_cred *cred = NULL;
	struct nfs4_state_owner *sp;
	struct rb_node *pos;

	for (pos = rb_first(&server->state_owners);
	     pos != NULL;
	     pos = rb_next(pos)) {
		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
		if (list_empty(&sp->so_states))
			continue;
		cred = get_rpccred(sp->so_cred);
		break;
	}
	return cred;
}

/**
 * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
 * @clp: client state handle
 *
 * Returns an rpc_cred with reference count bumped, or NULL.
 * Caller must hold clp->cl_lock.
 */
struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
{
	struct rpc_cred *cred = NULL;
	struct nfs_server *server;