nfs4state.c

			case -NFS4ERR_RECLAIM_BAD:
			case -NFS4ERR_RECLAIM_CONFLICT:
				/* kill_proc(fl->fl_pid, SIGLOST, 1); */
				status = 0;
		}
		lock_kernel();
	}
	unlock_kernel();
out:
	up_write(&nfsi->rwsem);
	return status;
}

static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops)
{
	struct nfs4_state *state;
	struct nfs4_lock_state *lock;
	int status = 0;

	/* Note: we rely on the sp->so_states list being ordered 
	 * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
	 * states first.
	 * This is needed to ensure that the server won't give us any
	 * read delegations that we have to return if, say, we are
	 * recovering after a network partition or a reboot from a
	 * server that doesn't support a grace period.
	 */
restart:
	spin_lock(&sp->so_lock);
	list_for_each_entry(state, &sp->so_states, open_states) {
		if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
			continue;
		if (state->state == 0)
			continue;
		atomic_inc(&state->count);
		spin_unlock(&sp->so_lock);
		status = ops->recover_open(sp, state);
		if (status >= 0) {
			status = nfs4_reclaim_locks(state, ops);
			if (status >= 0) {
				list_for_each_entry(lock, &state->lock_states, ls_locks) {
					if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
						printk("%s: Lock reclaim failed!\n",
							__func__);
				}
				nfs4_put_open_state(state);
				goto restart;
			}
		}
		switch (status) {
			default:
				printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
						__func__, status);
			case -ENOENT:
			case -ENOMEM:
			case -ESTALE:
				/*
				 * Open state on this file cannot be recovered
				 * All we can do is revert to using the zero stateid.
				 */
				memset(state->stateid.data, 0,
					sizeof(state->stateid.data));
				/* Mark the file as being 'closed' */
				state->state = 0;
				break;
			case -EKEYEXPIRED:
				/*
				 * User RPCSEC_GSS context has expired.
				 * We cannot recover this stateid now, so
				 * skip it and allow recovery thread to
				 * proceed.
				 */
				break;
			case -NFS4ERR_ADMIN_REVOKED:
			case -NFS4ERR_STALE_STATEID:
			case -NFS4ERR_BAD_STATEID:
			case -NFS4ERR_RECLAIM_BAD:
			case -NFS4ERR_RECLAIM_CONFLICT:
				nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
				break;
			case -NFS4ERR_EXPIRED:
			case -NFS4ERR_NO_GRACE:
				nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
			case -NFS4ERR_STALE_CLIENTID:
			case -NFS4ERR_BADSESSION:
			case -NFS4ERR_BADSLOT:
			case -NFS4ERR_BAD_HIGH_SLOT:
			case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
				goto out_err;
		}
		nfs4_put_open_state(state);
		goto restart;
	}
	spin_unlock(&sp->so_lock);
	return 0;
out_err:
	nfs4_put_open_state(state);
	return status;
}

static void nfs4_clear_open_state(struct nfs4_state *state)
{
	struct nfs4_lock_state *lock;

	clear_bit(NFS_DELEGATED_STATE, &state->flags);
	clear_bit(NFS_O_RDONLY_STATE, &state->flags);
	clear_bit(NFS_O_WRONLY_STATE, &state->flags);
	clear_bit(NFS_O_RDWR_STATE, &state->flags);
	list_for_each_entry(lock, &state->lock_states, ls_locks) {
		lock->ls_seqid.flags = 0;
		lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
	}
}

static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
{
	struct nfs4_state_owner *sp;
	struct rb_node *pos;
	struct nfs4_state *state;

	/* Reset all sequence ids to zero */
	for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
		sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
		sp->so_seqid.flags = 0;
		spin_lock(&sp->so_lock);
		list_for_each_entry(state, &sp->so_states, open_states) {
			if (mark_reclaim(clp, state))
				nfs4_clear_open_state(state);
		}
		spin_unlock(&sp->so_lock);
	}
}

static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
{
	/* Mark all delegations for reclaim */
	nfs_delegation_mark_reclaim(clp);
	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
}

static void nfs4_reclaim_complete(struct nfs_client *clp,
				 const struct nfs4_state_recovery_ops *ops)
{
	/* Notify the server we're done reclaiming our state */
	if (ops->reclaim_complete)
		(void)ops->reclaim_complete(clp);
}

static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
{
	struct nfs4_state_owner *sp;
	struct rb_node *pos;
	struct nfs4_state *state;

	if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
		return 0;

	for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
		sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
		spin_lock(&sp->so_lock);
		list_for_each_entry(state, &sp->so_states, open_states) {
			if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
				continue;
			nfs4_state_mark_reclaim_nograce(clp, state);
		}
		spin_unlock(&sp->so_lock);
	}

	nfs_delegation_reap_unclaimed(clp);
	return 1;
}

static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
{
	if (!nfs4_state_clear_reclaim_reboot(clp))
		return;
	nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
}

static void nfs_delegation_clear_all(struct nfs_client *clp)
{
	nfs_delegation_mark_reclaim(clp);
	nfs_delegation_reap_unclaimed(clp);
}

static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
{
	nfs_delegation_clear_all(clp);
	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
}

static void nfs4_warn_keyexpired(const char *s)
{
	printk_ratelimited(KERN_WARNING "Error: state manager"
			" encountered RPCSEC_GSS session"
			" expired against NFSv4 server %s.\n",
			s);
}

static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
{
	switch (error) {
		case -NFS4ERR_CB_PATH_DOWN:
			nfs_handle_cb_pathdown(clp);
			return 0;
		case -NFS4ERR_NO_GRACE:
			nfs4_state_end_reclaim_reboot(clp);
			return 0;
		case -NFS4ERR_STALE_CLIENTID:
		case -NFS4ERR_LEASE_MOVED:
			set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
			nfs4_state_clear_reclaim_reboot(clp);
			nfs4_state_start_reclaim_reboot(clp);
			break;
		case -NFS4ERR_EXPIRED:
			set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
			nfs4_state_start_reclaim_nograce(clp);
			break;
		case -NFS4ERR_BADSESSION:
		case -NFS4ERR_BADSLOT:
		case -NFS4ERR_BAD_HIGH_SLOT:
		case -NFS4ERR_DEADSESSION:
		case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
		case -NFS4ERR_SEQ_FALSE_RETRY:
		case -NFS4ERR_SEQ_MISORDERED:
			set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
			/* Zero session reset errors */
			return 0;
		case -EKEYEXPIRED:
			/* Nothing we can do */
			nfs4_warn_keyexpired(clp->cl_hostname);
			return 0;
	}
	return error;
}

static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
{
	struct rb_node *pos;
	int status = 0;

restart:
	spin_lock(&clp->cl_lock);
	for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
		struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
		if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
			continue;
		atomic_inc(&sp->so_count);
		spin_unlock(&clp->cl_lock);
		status = nfs4_reclaim_open_state(sp, ops);
		if (status < 0) {
			set_bit(ops->owner_flag_bit, &sp->so_flags);
			nfs4_put_state_owner(sp);
			return nfs4_recovery_handle_error(clp, status);
		}
		nfs4_put_state_owner(sp);
		goto restart;
	}
	spin_unlock(&clp->cl_lock);
	return status;
}

static int nfs4_check_lease(struct nfs_client *clp)
{
	struct rpc_cred *cred;
	const struct nfs4_state_maintenance_ops *ops =
		clp->cl_mvops->state_renewal_ops;
	int status = -NFS4ERR_EXPIRED;

	/* Is the client already known to have an expired lease? */
	if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
		return 0;
	spin_lock(&clp->cl_lock);
	cred = ops->get_state_renewal_cred_locked(clp);
	spin_unlock(&clp->cl_lock);
	if (cred == NULL) {
		cred = nfs4_get_setclientid_cred(clp);
		if (cred == NULL)
			goto out;
	}
	status = ops->renew_lease(clp, cred);
	put_rpccred(cred);
out:
	return nfs4_recovery_handle_error(clp, status);
}

static int nfs4_reclaim_lease(struct nfs_client *clp)
{
	struct rpc_cred *cred;
	const struct nfs4_state_recovery_ops *ops =
		clp->cl_mvops->reboot_recovery_ops;
	int status = -ENOENT;

	cred = ops->get_clid_cred(clp);
	if (cred != NULL) {
		status = ops->establish_clid(clp, cred);
		put_rpccred(cred);
		/* Handle case where the user hasn't set up machine creds */
		if (status == -EACCES && cred == clp->cl_machine_cred) {
			nfs4_clear_machine_cred(clp);
			status = -EAGAIN;
		}
		if (status == -NFS4ERR_MINOR_VERS_MISMATCH)
			status = -EPROTONOSUPPORT;
	}
	return status;
}

#ifdef CONFIG_NFS_V4_1
void nfs41_handle_recall_slot(struct nfs_client *clp)
{
	set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
	nfs4_schedule_state_recovery(clp);
}

static void nfs4_reset_all_state(struct nfs_client *clp)
{
	if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
		clp->cl_boot_time = CURRENT_TIME;
		nfs4_state_start_reclaim_nograce(clp);
		nfs4_schedule_state_recovery(clp);
	}
}

static void nfs41_handle_server_reboot(struct nfs_client *clp)
{
	if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
		nfs4_state_start_reclaim_reboot(clp);
		nfs4_schedule_state_recovery(clp);
	}
}

static void nfs41_handle_state_revoked(struct nfs_client *clp)
{
	/* Temporary */
	nfs4_reset_all_state(clp);
}

static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
{
	/* This will need to handle layouts too */
	nfs_expire_all_delegations(clp);
}

static void nfs41_handle_cb_path_down(struct nfs_client *clp)
{
	nfs_expire_all_delegations(clp);
	if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
		nfs4_schedule_state_recovery(clp);
}

void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
{
	if (!flags)
		return;
	else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
		nfs41_handle_server_reboot(clp);
	else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
			    SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
			    SEQ4_STATUS_ADMIN_STATE_REVOKED |
			    SEQ4_STATUS_LEASE_MOVED))
		nfs41_handle_state_revoked(clp);
	else if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
		nfs41_handle_recallable_state_revoked(clp);
	else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
			    SEQ4_STATUS_BACKCHANNEL_FAULT |
			    SEQ4_STATUS_CB_PATH_DOWN_SESSION))
		nfs41_handle_cb_path_down(clp);
}

static int nfs4_reset_session(struct nfs_client *clp)
{
	int status;

	nfs4_begin_drain_session(clp);
	status = nfs4_proc_destroy_session(clp->cl_session);
	if (status && status != -NFS4ERR_BADSESSION &&
	    status != -NFS4ERR_DEADSESSION) {
		status = nfs4_recovery_handle_error(clp, status);
		goto out;
	}

	memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
	status = nfs4_proc_create_session(clp);
	if (status) {
		status = nfs4_recovery_handle_error(clp, status);
		goto out;
	}
	/* create_session negotiated new slot table */
	clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);

	 /* Let the state manager reestablish state */
	if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
		nfs41_setup_state_renewal(clp);
out:
	return status;
}

static int nfs4_recall_slot(struct nfs_client *clp)
{
	struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
	struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
	struct nfs4_slot *new, *old;
	int i;

	nfs4_begin_drain_session(clp);
	new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
		      GFP_NOFS);
        if (!new)
		return -ENOMEM;

	spin_lock(&fc_tbl->slot_tbl_lock);
	for (i = 0; i < fc_tbl->target_max_slots; i++)
		new[i].seq_nr = fc_tbl->slots[i].seq_nr;
	old = fc_tbl->slots;
	fc_tbl->slots = new;
	fc_tbl->max_slots = fc_tbl->target_max_slots;
	fc_tbl->target_max_slots = 0;
	fc_attrs->max_reqs = fc_tbl->max_slots;
	spin_unlock(&fc_tbl->slot_tbl_lock);

	kfree(old);
	nfs4_end_drain_session(clp);
	return 0;
}

#else /* CONFIG_NFS_V4_1 */
static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
#endif /* CONFIG_NFS_V4_1 */

/* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
 * on EXCHANGE_ID for v4.1
 */
static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
{
	if (nfs4_has_session(clp)) {
		switch (status) {
		case -NFS4ERR_DELAY:
		case -NFS4ERR_CLID_INUSE:
		case -EAGAIN:
			break;

		case -EKEYEXPIRED:
			nfs4_warn_keyexpired(clp->cl_hostname);
		case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
					 * in nfs4_exchange_id */
		default:
			return;
		}
	}
	set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
}

static void nfs4_state_manager(struct nfs_client *clp)
{
	int status = 0;

	/* Ensure exclusive access to NFSv4 state */
	for(;;) {
		if (test_and_clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
			/* We're going to have to re-establish a clientid */
			status = nfs4_reclaim_lease(clp);
			if (status) {
				nfs4_set_lease_expired(clp, status);
				if (test_bit(NFS4CLNT_LEASE_EXPIRED,
							&clp->cl_state))
					continue;
				if (clp->cl_cons_state ==
							NFS_CS_SESSION_INITING)
					nfs_mark_client_ready(clp, status);
				goto out_error;
			}
			clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
			set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
		}

		if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
			status = nfs4_check_lease(clp);
			if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
				continue;
			if (status < 0 && status != -NFS4ERR_CB_PATH_DOWN)
				goto out_error;
		}

		/* Initialize or reset the session */
		if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
		   && nfs4_has_session(clp)) {
			status = nfs4_reset_session(clp);
			if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
				continue;
			if (status < 0)
				goto out_error;
		}

		/* First recover reboot state... */
		if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
			status = nfs4_do_reclaim(clp,
				clp->cl_mvops->reboot_recovery_ops);
			if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
			    test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
				continue;
			nfs4_state_end_reclaim_reboot(clp);
			if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
				continue;
			if (status < 0)
				goto out_error;
		}

		/* Now recover expired state... */
		if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
			status = nfs4_do_reclaim(clp,
				clp->cl_mvops->nograce_recovery_ops);
			if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
			    test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
			    test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
				continue;
			if (status < 0)
				goto out_error;
		}

		nfs4_end_drain_session(clp);
		if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
			nfs_client_return_marked_delegations(clp);
			continue;
		}
		/* Recall session slots */
		if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
		   && nfs4_has_session(clp)) {
			status = nfs4_recall_slot(clp);
			if (status < 0)
				goto out_error;
			continue;
		}


		nfs4_clear_state_manager_bit(clp);
		/* Did we race with an attempt to give us more work? */
		if (clp->cl_state == 0)
			break;
		if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
			break;
	}
	return;
out_error:
	printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
			" with error %d\n", clp->cl_hostname, -status);
	nfs4_end_drain_session(clp);
	nfs4_clear_state_manager_bit(clp);
}

static int nfs4_run_state_manager(void *ptr)
{
	struct nfs_client *clp = ptr;

	allow_signal(SIGKILL);
	nfs4_state_manager(clp);
	nfs_put_client(clp);
	module_put_and_exit(0);
	return 0;
}

/*
 * Local variables:
 *  c-basic-offset: 8
 * End:
 */