static int nfs4_xdr_dec_getattr(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
				void *data)
{
	struct nfs4_getattr_res *res = data;
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (status)
		goto out;
	status = decode_sequence(xdr, &res->seq_res, rqstp);
	if (status)
		goto out;
	status = decode_putfh(xdr);
	if (status)
		goto out;
	status = decode_getfattr_label(xdr, res->fattr, res->label, res->server);
out:
	return status;
}


nfs: Fix getxattr kernel panic and memory overflow

Move the buffer size check to decode_attr_security_label() before memcpy()
Only call memcpy() if the buffer is large enough

Fixes: aa9c2669626c ("NFS: Client implementation of Labeled-NFS")
Signed-off-by: Jeffrey Mitchell <jeffrey.mitchell@starlab.io>
[Trond: clean up duplicate test of label->len != 0]
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

static int nfs40_open_expired(struct nfs4_state_owner *sp, struct nfs4_state *state)
{
	/* NFSv4.0 doesn't allow for delegation recovery on open expire */
	nfs40_clear_delegation_stateid(state);
	nfs_state_clear_open_state_flags(state);
	return nfs4_open_expired(sp, state);
}

A TOCTOU mismatch in the NFS client code in the Linux kernel before 5.8.3 could be used by local attackers to corrupt memory or possibly have unspecified other impact because a size check is in fs/nfs/nfs4proc.c instead of fs/nfs/nfs4xdr.c, aka CID-b4487b935452.


static void nfs41_sequence_release(void *data)
{
	struct nfs4_sequence_data *calldata = data;
	struct nfs_client *clp = calldata->clp;

	if (refcount_read(&clp->cl_count) > 1)
		nfs4_schedule_state_renewal(clp);
	nfs_put_client(clp);
	kfree(calldata);
}


static int nfs40_test_and_free_expired_stateid(struct nfs_server *server,
		nfs4_stateid *stateid,
		const struct cred *cred)
{
	return -NFS4ERR_BAD_STATEID;
}


static void encode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 op,
		uint32_t replen,
		struct compound_hdr *hdr)
{
	encode_uint32(xdr, op);
	hdr->nops++;
	hdr->replen += replen;
}


static int nfs4_verify_fore_channel_attrs(struct nfs41_create_session_args *args,
		struct nfs41_create_session_res *res)
{
	struct nfs4_channel_attrs *sent = &args->fc_attrs;
	struct nfs4_channel_attrs *rcvd = &res->fc_attrs;

	if (rcvd->max_resp_sz > sent->max_resp_sz)
		return -EINVAL;
	/*
	 * Our requested max_ops is the minimum we need; we're not
	 * prepared to break up compounds into smaller pieces than that.
	 * So, no point even trying to continue if the server won't
	 * cooperate:
	 */
	if (rcvd->max_ops < sent->max_ops)
		return -EINVAL;
	if (rcvd->max_reqs == 0)
		return -EINVAL;
	if (rcvd->max_reqs > NFS4_MAX_SLOT_TABLE)
		rcvd->max_reqs = NFS4_MAX_SLOT_TABLE;
	return 0;
}


static void nfs4_init_opendata_res(struct nfs4_opendata *p)
{
	p->o_res.f_attr = &p->f_attr;
	p->o_res.f_label = p->f_label;
	p->o_res.seqid = p->o_arg.seqid;
	p->c_res.seqid = p->c_arg.seqid;
	p->o_res.server = p->o_arg.server;
	p->o_res.access_request = p->o_arg.access;
	nfs_fattr_init(&p->f_attr);
	nfs_fattr_init_names(&p->f_attr, &p->owner_name, &p->group_name);
}


static void nfs4_xdr_enc_secinfo_no_name(struct rpc_rqst *req,
					struct xdr_stream *xdr,
					const void *data)
{
	const struct nfs41_secinfo_no_name_args *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putrootfh(xdr, &hdr);
	encode_secinfo_no_name(xdr, args, &hdr);
	encode_nops(&hdr);
}


static void encode_lock(struct xdr_stream *xdr, const struct nfs_lock_args *args, struct compound_hdr *hdr)
{
	__be32 *p;

	encode_op_hdr(xdr, OP_LOCK, decode_lock_maxsz, hdr);
	p = reserve_space(xdr, 28);
	*p++ = cpu_to_be32(nfs4_lock_type(args->fl, args->block));
	*p++ = cpu_to_be32(args->reclaim);
	p = xdr_encode_hyper(p, args->fl->fl_start);
	p = xdr_encode_hyper(p, nfs4_lock_length(args->fl));
	*p = cpu_to_be32(args->new_lock_owner);
	if (args->new_lock_owner){
		encode_nfs4_seqid(xdr, args->open_seqid);
		encode_nfs4_stateid(xdr, &args->open_stateid);
		encode_nfs4_seqid(xdr, args->lock_seqid);
		encode_lockowner(xdr, &args->lock_owner);
	}
	else {
		encode_nfs4_stateid(xdr, &args->lock_stateid);
		encode_nfs4_seqid(xdr, args->lock_seqid);
	}
}


static void encode_destroy_session(struct xdr_stream *xdr,
				   const struct nfs4_session *session,
				   struct compound_hdr *hdr)
{
	encode_op_hdr(xdr, OP_DESTROY_SESSION, decode_destroy_session_maxsz, hdr);
	encode_opaque_fixed(xdr, session->sess_id.data, NFS4_MAX_SESSIONID_LEN);
}


static void nfs4_xdr_enc_statfs(struct rpc_rqst *req, struct xdr_stream *xdr,
				const void *data)
{
	const struct nfs4_statfs_arg *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_getattr(xdr, nfs4_statfs_bitmap, args->bitmask,
			ARRAY_SIZE(nfs4_statfs_bitmap), &hdr);
	encode_nops(&hdr);
}


static void nfs4_xdr_enc_getattr(struct rpc_rqst *req, struct xdr_stream *xdr,
				 const void *data)
{
	const struct nfs4_getattr_arg *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_getfattr(xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
}


int nfs4_proc_getdeviceinfo(struct nfs_server *server,
		struct pnfs_device *pdev,
		const struct cred *cred)
{
	struct nfs4_exception exception = { };
	int err;

	do {
		err = nfs4_handle_exception(server,
					_nfs4_proc_getdeviceinfo(server, pdev, cred),
					&exception);
	} while (exception.retry);
	return err;
}


static int nfs4_xdr_dec_bind_conn_to_session(struct rpc_rqst *rqstp,
					struct xdr_stream *xdr,
					void *res)
{
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (!status)
		status = decode_bind_conn_to_session(xdr, res);
	return status;
}


static void nfs4_xdr_enc_release_lockowner(struct rpc_rqst *req,
					   struct xdr_stream *xdr,
					   const void *data)
{
	const struct nfs_release_lockowner_args *args = data;
	struct compound_hdr hdr = {
		.minorversion = 0,
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_release_lockowner(xdr, &args->lock_owner, &hdr);
	encode_nops(&hdr);
}


static void encode_exchange_id(struct xdr_stream *xdr,
			       const struct nfs41_exchange_id_args *args,
			       struct compound_hdr *hdr)
{
	__be32 *p;
	char impl_name[IMPL_NAME_LIMIT];
	int len = 0;

	encode_op_hdr(xdr, OP_EXCHANGE_ID, decode_exchange_id_maxsz, hdr);
	encode_nfs4_verifier(xdr, &args->verifier);

	encode_string(xdr, strlen(args->client->cl_owner_id),
			args->client->cl_owner_id);

	encode_uint32(xdr, args->flags);
	encode_uint32(xdr, args->state_protect.how);

	switch (args->state_protect.how) {
	case SP4_NONE:
		break;
	case SP4_MACH_CRED:
		encode_op_map(xdr, &args->state_protect.enforce);
		encode_op_map(xdr, &args->state_protect.allow);
		break;
	default:
		WARN_ON_ONCE(1);
		break;
	}

	if (send_implementation_id &&
	    sizeof(CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN) > 1 &&
	    sizeof(CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN)
		<= sizeof(impl_name) + 1)
		len = snprintf(impl_name, sizeof(impl_name), "%s %s %s %s",
			       utsname()->sysname, utsname()->release,
			       utsname()->version, utsname()->machine);

	if (len > 0) {
		encode_uint32(xdr, 1);	/* implementation id array length=1 */

		encode_string(xdr,
			sizeof(CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN) - 1,
			CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN);
		encode_string(xdr, len, impl_name);
		/* just send zeros for nii_date - the date is in nii_name */
		p = reserve_space(xdr, 12);
		p = xdr_encode_hyper(p, 0);
		*p = cpu_to_be32(0);
	} else
		encode_uint32(xdr, 0);	/* implementation id array length=0 */
}


static int nfs41_sequence_process(struct rpc_task *task,
		struct nfs4_sequence_res *res)
{
	struct nfs4_session *session;
	struct nfs4_slot *slot = res->sr_slot;
	struct nfs_client *clp;
	int status;
	int ret = 1;

	if (slot == NULL)
		goto out_noaction;
	/* don't increment the sequence number if the task wasn't sent */
	if (!RPC_WAS_SENT(task) || slot->seq_done)
		goto out;

	session = slot->table->session;

	trace_nfs4_sequence_done(session, res);

	status = res->sr_status;
	if (task->tk_status == -NFS4ERR_DEADSESSION)
		status = -NFS4ERR_DEADSESSION;

	/* Check the SEQUENCE operation status */
	switch (status) {
	case 0:
		/* Mark this sequence number as having been acked */
		nfs4_slot_sequence_acked(slot, slot->seq_nr);
		/* Update the slot's sequence and clientid lease timer */
		slot->seq_done = 1;
		clp = session->clp;
		do_renew_lease(clp, res->sr_timestamp);
		/* Check sequence flags */
		nfs41_handle_sequence_flag_errors(clp, res->sr_status_flags,
				!!slot->privileged);
		nfs41_update_target_slotid(slot->table, slot, res);
		break;
	case 1:
		/*
		 * sr_status remains 1 if an RPC level error occurred.
		 * The server may or may not have processed the sequence
		 * operation..
		 */
		nfs4_slot_sequence_record_sent(slot, slot->seq_nr);
		slot->seq_done = 1;
		goto out;
	case -NFS4ERR_DELAY:
		/* The server detected a resend of the RPC call and
		 * returned NFS4ERR_DELAY as per Section 2.10.6.2
		 * of RFC5661.
		 */
		dprintk("%s: slot=%u seq=%u: Operation in progress\n",
			__func__,
			slot->slot_nr,
			slot->seq_nr);
		nfs4_slot_sequence_acked(slot, slot->seq_nr);
		goto out_retry;
	case -NFS4ERR_RETRY_UNCACHED_REP:
	case -NFS4ERR_SEQ_FALSE_RETRY:
		/*
		 * The server thinks we tried to replay a request.
		 * Retry the call after bumping the sequence ID.
		 */
		nfs4_slot_sequence_acked(slot, slot->seq_nr);
		goto retry_new_seq;
	case -NFS4ERR_BADSLOT:
		/*
		 * The slot id we used was probably retired. Try again
		 * using a different slot id.
		 */
		if (slot->slot_nr < slot->table->target_highest_slotid)
			goto session_recover;
		goto retry_nowait;
	case -NFS4ERR_SEQ_MISORDERED:
		nfs4_slot_sequence_record_sent(slot, slot->seq_nr);
		/*
		 * Were one or more calls using this slot interrupted?
		 * If the server never received the request, then our
		 * transmitted slot sequence number may be too high.
		 */
		if ((s32)(slot->seq_nr - slot->seq_nr_last_acked) > 1) {
			slot->seq_nr--;
			goto retry_nowait;
		}
		/*
		 * RFC5661:
		 * A retry might be sent while the original request is
		 * still in progress on the replier. The replier SHOULD
		 * deal with the issue by returning NFS4ERR_DELAY as the
		 * reply to SEQUENCE or CB_SEQUENCE operation, but
		 * implementations MAY return NFS4ERR_SEQ_MISORDERED.
		 *
		 * Restart the search after a delay.
		 */
		slot->seq_nr = slot->seq_nr_highest_sent;
		goto out_retry;
	case -NFS4ERR_BADSESSION:
	case -NFS4ERR_DEADSESSION:
	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
		goto session_recover;
	default:
		/* Just update the slot sequence no. */
		slot->seq_done = 1;
	}
out:
	/* The session may be reset by one of the error handlers. */
	dprintk("%s: Error %d free the slot \n", __func__, res->sr_status);
out_noaction:
	return ret;
session_recover:
	nfs4_schedule_session_recovery(session, status);
	dprintk("%s ERROR: %d Reset session\n", __func__, status);
	nfs41_sequence_free_slot(res);
	goto out;
retry_new_seq:
	++slot->seq_nr;
retry_nowait:
	if (rpc_restart_call_prepare(task)) {
		nfs41_sequence_free_slot(res);
		task->tk_status = 0;
		ret = 0;
	}
	goto out;
out_retry:
	if (!rpc_restart_call(task))
		goto out;
	rpc_delay(task, NFS4_POLL_RETRY_MAX);
	return 0;
}


int nfs4_destroy_clientid(struct nfs_client *clp)
{
	const struct cred *cred;
	int ret = 0;

	if (clp->cl_mvops->minor_version < 1)
		goto out;
	if (clp->cl_exchange_flags == 0)
		goto out;
	if (clp->cl_preserve_clid)
		goto out;
	cred = nfs4_get_clid_cred(clp);
	ret = nfs4_proc_destroy_clientid(clp, cred);
	put_cred(cred);
	switch (ret) {
	case 0:
	case -NFS4ERR_STALE_CLIENTID:
		clp->cl_exchange_flags = 0;
	}
out:
	return ret;
}


static int nfs4_xattr_set_nfs4_user(const struct xattr_handler *handler,
				    struct dentry *unused, struct inode *inode,
				    const char *key, const void *buf,
				    size_t buflen, int flags)
{
	struct nfs_access_entry cache;
	int ret;

	if (!nfs_server_capable(inode, NFS_CAP_XATTR))
		return -EOPNOTSUPP;

	/*
	 * There is no mapping from the MAY_* flags to the NFS_ACCESS_XA*
	 * flags right now. Handling of xattr operations use the normal
	 * file read/write permissions.
	 *
	 * Just in case the server has other ideas (which RFC 8276 allows),
	 * do a cached access check for the XA* flags to possibly avoid
	 * doing an RPC and getting EACCES back.
	 */
	if (!nfs_access_get_cached(inode, current_cred(), &cache, true)) {
		if (!(cache.mask & NFS_ACCESS_XAWRITE))
			return -EACCES;
	}

	if (buf == NULL) {
		ret = nfs42_proc_removexattr(inode, key);
		if (!ret)
			nfs4_xattr_cache_remove(inode, key);
	} else {
		ret = nfs42_proc_setxattr(inode, key, buf, buflen, flags);
		if (!ret)
			nfs4_xattr_cache_add(inode, key, buf, NULL, buflen);
	}

	return ret;
}


static int decode_attr_space_avail(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 0;
	if (unlikely(bitmap[1] & (FATTR4_WORD1_SPACE_AVAIL - 1U)))
		return -EIO;
	if (likely(bitmap[1] & FATTR4_WORD1_SPACE_AVAIL)) {
		p = xdr_inline_decode(xdr, 8);
		if (unlikely(!p))
			return -EIO;
		xdr_decode_hyper(p, res);
		bitmap[1] &= ~FATTR4_WORD1_SPACE_AVAIL;
	}
	dprintk("%s: space avail=%Lu\n", __func__, (unsigned long long)*res);
	return status;
}


static void nfs4_xdr_enc_symlink(struct rpc_rqst *req, struct xdr_stream *xdr,
				 const void *data)
{
	const struct nfs4_create_arg *args = data;

	nfs4_xdr_enc_create(req, xdr, args);
}


static struct nfs4_opendata *nfs4_open_recoverdata_alloc(struct nfs_open_context *ctx,
		struct nfs4_state *state, enum open_claim_type4 claim)
{
	struct nfs4_opendata *opendata;

	opendata = nfs4_opendata_alloc(ctx->dentry, state->owner, 0, 0,
			NULL, claim, GFP_NOFS);
	if (opendata == NULL)
		return ERR_PTR(-ENOMEM);
	opendata->state = state;
	refcount_inc(&state->count);
	return opendata;
}


static int decode_attr_space_total(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 0;
	if (unlikely(bitmap[1] & (FATTR4_WORD1_SPACE_TOTAL - 1U)))
		return -EIO;
	if (likely(bitmap[1] & FATTR4_WORD1_SPACE_TOTAL)) {
		p = xdr_inline_decode(xdr, 8);
		if (unlikely(!p))
			return -EIO;
		xdr_decode_hyper(p, res);
		bitmap[1] &= ~FATTR4_WORD1_SPACE_TOTAL;
	}
	dprintk("%s: space total=%Lu\n", __func__, (unsigned long long)*res);
	return status;
}


static int nfs4_proc_lookupp(struct inode *inode, struct nfs_fh *fhandle,
			     struct nfs_fattr *fattr, struct nfs4_label *label)
{
	struct nfs4_exception exception = {
		.interruptible = true,
	};
	int err;
	do {
		err = _nfs4_proc_lookupp(inode, fhandle, fattr, label);
		trace_nfs4_lookupp(inode, err);
		err = nfs4_handle_exception(NFS_SERVER(inode), err,
				&exception);
	} while (exception.retry);
	return err;
}


nfs4_retry_setlk(struct nfs4_state *state, int cmd, struct file_lock *request)
{
	int status = -ERESTARTSYS;
	struct nfs4_lock_state *lsp = request->fl_u.nfs4_fl.owner;
	struct nfs_server *server = NFS_SERVER(state->inode);
	struct nfs_client *clp = server->nfs_client;
	wait_queue_head_t *q = &clp->cl_lock_waitq;
	struct nfs_lowner owner = { .clientid = clp->cl_clientid,
				    .id = lsp->ls_seqid.owner_id,
				    .s_dev = server->s_dev };
	struct nfs4_lock_waiter waiter = { .task  = current,
					   .inode = state->inode,
					   .owner = &owner};
	wait_queue_entry_t wait;

	/* Don't bother with waitqueue if we don't expect a callback */
	if (!test_bit(NFS_STATE_MAY_NOTIFY_LOCK, &state->flags))
		return nfs4_retry_setlk_simple(state, cmd, request);

	init_wait(&wait);
	wait.private = &waiter;
	wait.func = nfs4_wake_lock_waiter;

	while(!signalled()) {
		add_wait_queue(q, &wait);
		status = nfs4_proc_setlk(state, cmd, request);
		if ((status != -EAGAIN) || IS_SETLK(cmd)) {
			finish_wait(q, &wait);
			break;
		}

		status = -ERESTARTSYS;
		freezer_do_not_count();
		wait_woken(&wait, TASK_INTERRUPTIBLE, NFS4_LOCK_MAXTIMEOUT);
		freezer_count();
		finish_wait(q, &wait);
	}

	return status;
}


static void nfs4_locku_release_calldata(void *data)
{
	struct nfs4_unlockdata *calldata = data;
	nfs_free_seqid(calldata->arg.seqid);
	nfs4_put_lock_state(calldata->lsp);
	nfs_put_lock_context(calldata->l_ctx);
	put_nfs_open_context(calldata->ctx);
	kfree(calldata);
}


static int decode_ace(struct xdr_stream *xdr, void *ace)
{
	__be32 *p;
	unsigned int strlen;
	char *str;

	p = xdr_inline_decode(xdr, 12);
	if (unlikely(!p))
		return -EIO;
	return decode_opaque_inline(xdr, &strlen, &str);
}


static void renew_lease(const struct nfs_server *server, unsigned long timestamp)
{
	struct nfs_client *clp = server->nfs_client;

	if (!nfs4_has_session(clp))
		do_renew_lease(clp, timestamp);
}


static void nfs_test_and_clear_all_open_stateid(struct nfs4_state *state)
{
	struct nfs_client *clp = state->owner->so_server->nfs_client;
	bool need_recover = false;

	if (test_and_clear_bit(NFS_O_RDONLY_STATE, &state->flags) && state->n_rdonly)
		need_recover = true;
	if (test_and_clear_bit(NFS_O_WRONLY_STATE, &state->flags) && state->n_wronly)
		need_recover = true;
	if (test_and_clear_bit(NFS_O_RDWR_STATE, &state->flags) && state->n_rdwr)
		need_recover = true;
	if (need_recover)
		nfs4_state_mark_reclaim_nograce(clp, state);
}


static int nfs4_delay_killable(long *timeout)
{
	might_sleep();

	freezable_schedule_timeout_killable_unsafe(
		nfs4_update_delay(timeout));
	if (!__fatal_signal_pending(current))
		return 0;
	return -EINTR;
}


static void nfs41_delegation_recover_stateid(struct nfs4_state *state)
{
	nfs4_stateid tmp;

	if (test_bit(NFS_DELEGATED_STATE, &state->flags) &&
	    nfs4_copy_delegation_stateid(state->inode, state->state,
				&tmp, NULL) &&
	    nfs4_stateid_match_other(&state->stateid, &tmp))
		nfs_state_set_delegation(state, &tmp, state->state);
	else
		nfs_state_clear_delegation(state);
}


static inline void encode_claim_fh(struct xdr_stream *xdr)
{
	__be32 *p;

	p = reserve_space(xdr, 4);
	*p = cpu_to_be32(NFS4_OPEN_CLAIM_FH);
}


static int decode_change_info(struct xdr_stream *xdr, struct nfs4_change_info *cinfo)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 20);
	if (unlikely(!p))
		return -EIO;
	cinfo->atomic = be32_to_cpup(p++);
	p = xdr_decode_hyper(p, &cinfo->before);
	xdr_decode_hyper(p, &cinfo->after);
	return 0;
}


static int nfs41_reclaim_complete_handle_errors(struct rpc_task *task, struct nfs_client *clp)
{
	switch(task->tk_status) {
	case 0:
		wake_up_all(&clp->cl_lock_waitq);
		/* Fallthrough */
	case -NFS4ERR_COMPLETE_ALREADY:
	case -NFS4ERR_WRONG_CRED: /* What to do here? */
		break;
	case -NFS4ERR_DELAY:
		rpc_delay(task, NFS4_POLL_RETRY_MAX);
		/* fall through */
	case -NFS4ERR_RETRY_UNCACHED_REP:
		return -EAGAIN;
	case -NFS4ERR_BADSESSION:
	case -NFS4ERR_DEADSESSION:
	case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
		break;
	default:
		nfs4_schedule_lease_recovery(clp);
	}
	return 0;
}


static void nfs4_xdr_enc_setacl(struct rpc_rqst *req, struct xdr_stream *xdr,
				const void *data)
{
	const struct nfs_setaclargs *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_setacl(xdr, args, &hdr);
	encode_nops(&hdr);
}


static void nfs4_xdr_enc_getdeviceinfo(struct rpc_rqst *req,
				       struct xdr_stream *xdr,
				       const void *data)
{
	const struct nfs4_getdeviceinfo_args *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_getdeviceinfo(xdr, args, &hdr);

	/* set up reply kvec. Subtract notification bitmap max size (2)
	 * so that notification bitmap is put in xdr_buf tail */
	rpc_prepare_reply_pages(req, args->pdev->pages, args->pdev->pgbase,
				args->pdev->pglen, hdr.replen - 2);
	encode_nops(&hdr);
}


static void nfs4_lock_done(struct rpc_task *task, void *calldata)
{
	struct nfs4_lockdata *data = calldata;
	struct nfs4_lock_state *lsp = data->lsp;

	dprintk("%s: begin!\n", __func__);

	if (!nfs4_sequence_done(task, &data->res.seq_res))
		return;

	data->rpc_status = task->tk_status;
	switch (task->tk_status) {
	case 0:
		renew_lease(NFS_SERVER(d_inode(data->ctx->dentry)),
				data->timestamp);
		if (data->arg.new_lock && !data->cancelled) {
			data->fl.fl_flags &= ~(FL_SLEEP | FL_ACCESS);
			if (locks_lock_inode_wait(lsp->ls_state->inode, &data->fl) < 0)
				goto out_restart;
		}
		if (data->arg.new_lock_owner != 0) {
			nfs_confirm_seqid(&lsp->ls_seqid, 0);
			nfs4_stateid_copy(&lsp->ls_stateid, &data->res.stateid);
			set_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags);
		} else if (!nfs4_update_lock_stateid(lsp, &data->res.stateid))
			goto out_restart;
		break;
	case -NFS4ERR_BAD_STATEID:
	case -NFS4ERR_OLD_STATEID:
	case -NFS4ERR_STALE_STATEID:
	case -NFS4ERR_EXPIRED:
		if (data->arg.new_lock_owner != 0) {
			if (!nfs4_stateid_match(&data->arg.open_stateid,
						&lsp->ls_state->open_stateid))
				goto out_restart;
		} else if (!nfs4_stateid_match(&data->arg.lock_stateid,
						&lsp->ls_stateid))
				goto out_restart;
	}
out_done:
	dprintk("%s: done, ret = %d!\n", __func__, data->rpc_status);
	return;
out_restart:
	if (!data->cancelled)
		rpc_restart_call_prepare(task);
	goto out_done;
}


static void nfs4_xdr_enc_open_confirm(struct rpc_rqst *req,
				      struct xdr_stream *xdr,
				      const void *data)
{
	const struct nfs_open_confirmargs *args = data;
	struct compound_hdr hdr = {
		.nops   = 0,
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_open_confirm(xdr, args, &hdr);
	encode_nops(&hdr);
}


static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
{
	unsigned int savep;
	uint32_t attrlen, bitmap[3];
	int status;

	if ((status = decode_op_hdr(xdr, OP_GETATTR)) != 0)
		goto xdr_error;
	if ((status = decode_attr_bitmap(xdr, bitmap)) != 0)
		goto xdr_error;
	if ((status = decode_attr_length(xdr, &attrlen, &savep)) != 0)
		goto xdr_error;

	fsinfo->rtmult = fsinfo->wtmult = 512;	/* ??? */

	if ((status = decode_attr_lease_time(xdr, bitmap, &fsinfo->lease_time)) != 0)
		goto xdr_error;
	if ((status = decode_attr_maxfilesize(xdr, bitmap, &fsinfo->maxfilesize)) != 0)
		goto xdr_error;
	if ((status = decode_attr_maxread(xdr, bitmap, &fsinfo->rtmax)) != 0)
		goto xdr_error;
	fsinfo->rtpref = fsinfo->dtpref = fsinfo->rtmax;
	if ((status = decode_attr_maxwrite(xdr, bitmap, &fsinfo->wtmax)) != 0)
		goto xdr_error;
	fsinfo->wtpref = fsinfo->wtmax;

	status = -EIO;
	if (unlikely(bitmap[0]))
		goto xdr_error;

	status = decode_attr_time_delta(xdr, bitmap, &fsinfo->time_delta);
	if (status != 0)
		goto xdr_error;
	status = decode_attr_pnfstype(xdr, bitmap, fsinfo);
	if (status != 0)
		goto xdr_error;

	status = -EIO;
	if (unlikely(bitmap[1]))
		goto xdr_error;

	status = decode_attr_layout_blksize(xdr, bitmap, &fsinfo->blksize);
	if (status)
		goto xdr_error;
	status = decode_attr_clone_blksize(xdr, bitmap, &fsinfo->clone_blksize);
	if (status)
		goto xdr_error;

	status = decode_attr_xattrsupport(xdr, bitmap,
					  &fsinfo->xattr_support);
	if (status)
		goto xdr_error;

	status = verify_attr_len(xdr, savep, attrlen);
xdr_error:
	dprintk("%s: xdr returned %d!\n", __func__, -status);
	return status;
}


static void nfs4_init_channel_attrs(struct nfs41_create_session_args *args,
				    struct rpc_clnt *clnt)
{
	unsigned int max_rqst_sz, max_resp_sz;
	unsigned int max_bc_payload = rpc_max_bc_payload(clnt);
	unsigned int max_bc_slots = rpc_num_bc_slots(clnt);

	max_rqst_sz = NFS_MAX_FILE_IO_SIZE + nfs41_maxwrite_overhead;
	max_resp_sz = NFS_MAX_FILE_IO_SIZE + nfs41_maxread_overhead;

	/* Fore channel attributes */
	args->fc_attrs.max_rqst_sz = max_rqst_sz;
	args->fc_attrs.max_resp_sz = max_resp_sz;
	args->fc_attrs.max_ops = NFS4_MAX_OPS;
	args->fc_attrs.max_reqs = max_session_slots;

	dprintk("%s: Fore Channel : max_rqst_sz=%u max_resp_sz=%u "
		"max_ops=%u max_reqs=%u\n",
		__func__,
		args->fc_attrs.max_rqst_sz, args->fc_attrs.max_resp_sz,
		args->fc_attrs.max_ops, args->fc_attrs.max_reqs);

	/* Back channel attributes */
	args->bc_attrs.max_rqst_sz = max_bc_payload;
	args->bc_attrs.max_resp_sz = max_bc_payload;
	args->bc_attrs.max_resp_sz_cached = 0;
	args->bc_attrs.max_ops = NFS4_MAX_BACK_CHANNEL_OPS;
	args->bc_attrs.max_reqs = max_t(unsigned short, max_session_cb_slots, 1);
	if (args->bc_attrs.max_reqs > max_bc_slots)
		args->bc_attrs.max_reqs = max_bc_slots;

	dprintk("%s: Back Channel : max_rqst_sz=%u max_resp_sz=%u "
		"max_resp_sz_cached=%u max_ops=%u max_reqs=%u\n",
		__func__,
		args->bc_attrs.max_rqst_sz, args->bc_attrs.max_resp_sz,
		args->bc_attrs.max_resp_sz_cached, args->bc_attrs.max_ops,
		args->bc_attrs.max_reqs);
}


encode_secinfo_no_name(struct xdr_stream *xdr,
		       const struct nfs41_secinfo_no_name_args *args,
		       struct compound_hdr *hdr)
{
	encode_op_hdr(xdr, OP_SECINFO_NO_NAME, decode_secinfo_no_name_maxsz, hdr);
	encode_uint32(xdr, args->style);
	return 0;
}


static int nfs4_proc_unlink_done(struct rpc_task *task, struct inode *dir)
{
	struct nfs_unlinkdata *data = task->tk_calldata;
	struct nfs_removeres *res = &data->res;

	if (!nfs4_sequence_done(task, &res->seq_res))
		return 0;
	if (nfs4_async_handle_error(task, res->server, NULL,
				    &data->timeout) == -EAGAIN)
		return 0;
	if (task->tk_status == 0)
		nfs4_update_changeattr(dir, &res->cinfo,
				res->dir_attr->time_start,
				NFS_INO_INVALID_DATA);
	return 1;
}


static int decode_op_map(struct xdr_stream *xdr, struct nfs4_op_map *op_map)
{
	__be32 *p;
	uint32_t bitmap_words;
	unsigned int i;

	p = xdr_inline_decode(xdr, 4);
	if (!p)
		return -EIO;
	bitmap_words = be32_to_cpup(p++);
	if (bitmap_words > NFS4_OP_MAP_NUM_WORDS)
		return -EIO;
	p = xdr_inline_decode(xdr, 4 * bitmap_words);
	for (i = 0; i < bitmap_words; i++)
		op_map->u.words[i] = be32_to_cpup(p++);

	return 0;
}


static int decode_space_limit(struct xdr_stream *xdr,
		unsigned long *pagemod_limit)
{
	__be32 *p;
	uint32_t limit_type, nblocks, blocksize;
	u64 maxsize = 0;

	p = xdr_inline_decode(xdr, 12);
	if (unlikely(!p))
		return -EIO;
	limit_type = be32_to_cpup(p++);
	switch (limit_type) {
	case NFS4_LIMIT_SIZE:
		xdr_decode_hyper(p, &maxsize);
		break;
	case NFS4_LIMIT_BLOCKS:
		nblocks = be32_to_cpup(p++);
		blocksize = be32_to_cpup(p);
		maxsize = (uint64_t)nblocks * (uint64_t)blocksize;
	}
	maxsize >>= PAGE_SHIFT;
	*pagemod_limit = min_t(u64, maxsize, ULONG_MAX);
	return 0;
}


static int nfs4_xdr_dec_read(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
			     void *data)
{
	struct nfs_pgio_res *res = data;
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	res->op_status = hdr.status;
	if (status)
		goto out;
	status = decode_sequence(xdr, &res->seq_res, rqstp);
	if (status)
		goto out;
	status = decode_putfh(xdr);
	if (status)
		goto out;
	status = decode_read(xdr, rqstp, res);
	if (!status)
		status = res->count;
out:
	return status;
}


static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
		int flags, struct nfs_open_context *ctx)
{
	struct nfs4_state_owner *sp = opendata->owner;
	struct nfs_server *server = sp->so_server;
	struct dentry *dentry;
	struct nfs4_state *state;
	fmode_t acc_mode = _nfs4_ctx_to_accessmode(ctx);
	struct inode *dir = d_inode(opendata->dir);
	unsigned long dir_verifier;
	unsigned int seq;
	int ret;

	seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
	dir_verifier = nfs_save_change_attribute(dir);

	ret = _nfs4_proc_open(opendata, ctx);
	if (ret != 0)
		goto out;

	state = _nfs4_opendata_to_nfs4_state(opendata);
	ret = PTR_ERR(state);
	if (IS_ERR(state))
		goto out;
	ctx->state = state;
	if (server->caps & NFS_CAP_POSIX_LOCK)
		set_bit(NFS_STATE_POSIX_LOCKS, &state->flags);
	if (opendata->o_res.rflags & NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK)
		set_bit(NFS_STATE_MAY_NOTIFY_LOCK, &state->flags);

	dentry = opendata->dentry;
	if (d_really_is_negative(dentry)) {
		struct dentry *alias;
		d_drop(dentry);
		alias = d_exact_alias(dentry, state->inode);
		if (!alias)
			alias = d_splice_alias(igrab(state->inode), dentry);
		/* d_splice_alias() can't fail here - it's a non-directory */
		if (alias) {
			dput(ctx->dentry);
			ctx->dentry = dentry = alias;
		}
	}

	switch(opendata->o_arg.claim) {
	default:
		break;
	case NFS4_OPEN_CLAIM_NULL:
	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
		if (!opendata->rpc_done)
			break;
		if (opendata->o_res.delegation_type != 0)
			dir_verifier = nfs_save_change_attribute(dir);
		nfs_set_verifier(dentry, dir_verifier);
	}

	/* Parse layoutget results before we check for access */
	pnfs_parse_lgopen(state->inode, opendata->lgp, ctx);

	ret = nfs4_opendata_access(sp->so_cred, opendata, state,
			acc_mode, flags);
	if (ret != 0)
		goto out;

	if (d_inode(dentry) == state->inode) {
		nfs_inode_attach_open_context(ctx);
		if (read_seqcount_retry(&sp->so_reclaim_seqcount, seq))
			nfs4_schedule_stateid_recovery(server, state);
	}

out:
	if (!opendata->cancelled)
		nfs4_sequence_free_slot(&opendata->o_res.seq_res);
	return ret;
}


static void nfs4_layoutreturn_release(void *calldata)
{
	struct nfs4_layoutreturn *lrp = calldata;
	struct pnfs_layout_hdr *lo = lrp->args.layout;

	dprintk("--> %s\n", __func__);
	pnfs_layoutreturn_free_lsegs(lo, &lrp->args.stateid, &lrp->args.range,
			lrp->res.lrs_present ? &lrp->res.stateid : NULL);
	nfs4_sequence_free_slot(&lrp->res.seq_res);
	if (lrp->ld_private.ops && lrp->ld_private.ops->free)
		lrp->ld_private.ops->free(&lrp->ld_private);
	pnfs_put_layout_hdr(lrp->args.layout);
	nfs_iput_and_deactive(lrp->inode);
	put_cred(lrp->cred);
	kfree(calldata);
	dprintk("<-- %s\n", __func__);
}


static int decode_invalid_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
{
	nfs4_stateid dummy;

	nfs4_stateid_copy(stateid, &invalid_stateid);
	return decode_stateid(xdr, &dummy);
}


static bool nfs4_clear_cap_atomic_open_v1(struct nfs_server *server,
		int err, struct nfs4_exception *exception)
{
	if (err != -EINVAL)
		return false;
	if (!(server->caps & NFS_CAP_ATOMIC_OPEN_V1))
		return false;
	server->caps &= ~NFS_CAP_ATOMIC_OPEN_V1;
	exception->retry = 1;
	return true;
}


static void encode_read(struct xdr_stream *xdr, const struct nfs_pgio_args *args,
			struct compound_hdr *hdr)
{
	__be32 *p;

	encode_op_hdr(xdr, OP_READ, decode_read_maxsz, hdr);
	encode_nfs4_stateid(xdr, &args->stateid);

	p = reserve_space(xdr, 12);
	p = xdr_encode_hyper(p, args->offset);
	*p = cpu_to_be32(args->count);
}


static void encode_getfattr(struct xdr_stream *xdr, const u32* bitmask, struct compound_hdr *hdr)
{
	encode_getattr(xdr, nfs4_fattr_bitmap, bitmask,
			ARRAY_SIZE(nfs4_fattr_bitmap), hdr);
}


static void nfs4_setup_readdir(u64 cookie, __be32 *verifier, struct dentry *dentry,
		struct nfs4_readdir_arg *readdir)
{
	unsigned int attrs = FATTR4_WORD0_FILEID | FATTR4_WORD0_TYPE;
	__be32 *start, *p;

	if (cookie > 2) {
		readdir->cookie = cookie;
		memcpy(&readdir->verifier, verifier, sizeof(readdir->verifier));
		return;
	}

	readdir->cookie = 0;
	memset(&readdir->verifier, 0, sizeof(readdir->verifier));
	if (cookie == 2)
		return;

	/*
	 * NFSv4 servers do not return entries for '.' and '..'
	 * Therefore, we fake these entries here.  We let '.'
	 * have cookie 0 and '..' have cookie 1.  Note that
	 * when talking to the server, we always send cookie 0
	 * instead of 1 or 2.
	 */
	start = p = kmap_atomic(*readdir->pages);

	if (cookie == 0) {
		*p++ = xdr_one;                                  /* next */
		*p++ = xdr_zero;                   /* cookie, first word */
		*p++ = xdr_one;                   /* cookie, second word */
		*p++ = xdr_one;                             /* entry len */
		memcpy(p, ".\0\0\0", 4);                        /* entry */
		p++;
		*p++ = xdr_one;                         /* bitmap length */
		*p++ = htonl(attrs);                           /* bitmap */
		*p++ = htonl(12);             /* attribute buffer length */
		*p++ = htonl(NF4DIR);
		p = xdr_encode_hyper(p, NFS_FILEID(d_inode(dentry)));
	}

	*p++ = xdr_one;                                  /* next */
	*p++ = xdr_zero;                   /* cookie, first word */
	*p++ = xdr_two;                   /* cookie, second word */
	*p++ = xdr_two;                             /* entry len */
	memcpy(p, "..\0\0", 4);                         /* entry */
	p++;
	*p++ = xdr_one;                         /* bitmap length */
	*p++ = htonl(attrs);                           /* bitmap */
	*p++ = htonl(12);             /* attribute buffer length */
	*p++ = htonl(NF4DIR);
	p = xdr_encode_hyper(p, NFS_FILEID(d_inode(dentry->d_parent)));

	readdir->pgbase = (char *)p - (char *)start;
	readdir->count -= readdir->pgbase;
	kunmap_atomic(start);
}


static int decode_lock_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
{
	stateid->type = NFS4_LOCK_STATEID_TYPE;
	return decode_stateid(xdr, stateid);
}


static int nfs4_xdr_dec_exchange_id(struct rpc_rqst *rqstp,
				    struct xdr_stream *xdr,
				    void *res)
{
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (!status)
		status = decode_exchange_id(xdr, res);
	return status;
}


int nfs4_proc_get_rootfh(struct nfs_server *server, struct nfs_fh *fhandle,
			 struct nfs_fsinfo *info,
			 bool auth_probe)
{
	int status = 0;

	if (!auth_probe)
		status = nfs4_lookup_root(server, fhandle, info);

	if (auth_probe || status == NFS4ERR_WRONGSEC)
		status = server->nfs_client->cl_mvops->find_root_sec(server,
				fhandle, info);

	if (status == 0)
		status = nfs4_server_capabilities(server, fhandle);
	if (status == 0)
		status = nfs4_do_fsinfo(server, fhandle, info);

	return nfs4_map_errors(status);
}


static void nfs41_release_slot(struct nfs4_slot *slot)
{
	struct nfs4_session *session;
	struct nfs4_slot_table *tbl;
	bool send_new_highest_used_slotid = false;

	if (!slot)
		return;
	tbl = slot->table;
	session = tbl->session;

	/* Bump the slot sequence number */
	if (slot->seq_done)
		slot->seq_nr++;
	slot->seq_done = 0;

	spin_lock(&tbl->slot_tbl_lock);
	/* Be nice to the server: try to ensure that the last transmitted
	 * value for highest_user_slotid <= target_highest_slotid
	 */
	if (tbl->highest_used_slotid > tbl->target_highest_slotid)
		send_new_highest_used_slotid = true;

	if (nfs41_wake_and_assign_slot(tbl, slot)) {
		send_new_highest_used_slotid = false;
		goto out_unlock;
	}
	nfs4_free_slot(tbl, slot);

	if (tbl->highest_used_slotid != NFS4_NO_SLOT)
		send_new_highest_used_slotid = false;
out_unlock:
	spin_unlock(&tbl->slot_tbl_lock);
	if (send_new_highest_used_slotid)
		nfs41_notify_server(session->clp);
	if (waitqueue_active(&tbl->slot_waitq))
		wake_up_all(&tbl->slot_waitq);
}


static void nfs4_exchange_id_release(void *data)
{
	struct nfs41_exchange_id_data *cdata =
					(struct nfs41_exchange_id_data *)data;

	nfs_put_client(cdata->args.client);
	kfree(cdata->res.impl_id);
	kfree(cdata->res.server_scope);
	kfree(cdata->res.server_owner);
	kfree(cdata);
}


static int decode_pathconf(struct xdr_stream *xdr, struct nfs_pathconf *pathconf)
{
	unsigned int savep;
	uint32_t attrlen, bitmap[3] = {0};
	int status;

	if ((status = decode_op_hdr(xdr, OP_GETATTR)) != 0)
		goto xdr_error;
	if ((status = decode_attr_bitmap(xdr, bitmap)) != 0)
		goto xdr_error;
	if ((status = decode_attr_length(xdr, &attrlen, &savep)) != 0)
		goto xdr_error;

	if ((status = decode_attr_maxlink(xdr, bitmap, &pathconf->max_link)) != 0)
		goto xdr_error;
	if ((status = decode_attr_maxname(xdr, bitmap, &pathconf->max_namelen)) != 0)
		goto xdr_error;

	status = verify_attr_len(xdr, savep, attrlen);
xdr_error:
	dprintk("%s: xdr returned %d!\n", __func__, -status);
	return status;
}


nfs4_map_atomic_open_claim(struct nfs_server *server,
		enum open_claim_type4 claim)
{
	if (server->caps & NFS_CAP_ATOMIC_OPEN_V1)
		return claim;
	switch (claim) {
	default:
		return claim;
	case NFS4_OPEN_CLAIM_FH:
		return NFS4_OPEN_CLAIM_NULL;
	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
		return NFS4_OPEN_CLAIM_DELEGATE_CUR;
	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
		return NFS4_OPEN_CLAIM_DELEGATE_PREV;
	}
}


static int decode_attr_xattrsupport(struct xdr_stream *xdr, uint32_t *bitmap,
				    uint32_t *res)
{
	__be32 *p;

	*res = 0;
	if (unlikely(bitmap[2] & (FATTR4_WORD2_XATTR_SUPPORT - 1U)))
		return -EIO;
	if (likely(bitmap[2] & FATTR4_WORD2_XATTR_SUPPORT)) {
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(!p))
			return -EIO;
		*res = be32_to_cpup(p);
		bitmap[2] &= ~FATTR4_WORD2_XATTR_SUPPORT;
	}
	dprintk("%s: XATTR support=%s\n", __func__,
		*res == 0 ? "false" : "true");
	return 0;
}


static void encode_lookup(struct xdr_stream *xdr, const struct qstr *name, struct compound_hdr *hdr)
{
	encode_op_hdr(xdr, OP_LOOKUP, decode_lookup_maxsz, hdr);
	encode_string(xdr, name->len, name->name);
}


static bool nfs4_stateid_is_current(nfs4_stateid *stateid,
		const struct nfs_open_context *ctx,
		const struct nfs_lock_context *l_ctx,
		fmode_t fmode)
{
	nfs4_stateid _current_stateid;

	/* If the current stateid represents a lost lock, then exit */
	if (nfs4_set_rw_stateid(&_current_stateid, ctx, l_ctx, fmode) == -EIO)
		return true;
	return nfs4_stateid_match(stateid, &_current_stateid);
}


static int decode_rw_delegation(struct xdr_stream *xdr,
		uint32_t delegation_type,
		struct nfs_openres *res)
{
	__be32 *p;
	int status;

	status = decode_delegation_stateid(xdr, &res->delegation);
	if (unlikely(status))
		return status;
	p = xdr_inline_decode(xdr, 4);
	if (unlikely(!p))
		return -EIO;
	res->do_recall = be32_to_cpup(p);

	switch (delegation_type) {
	case NFS4_OPEN_DELEGATE_READ:
		res->delegation_type = FMODE_READ;
		break;
	case NFS4_OPEN_DELEGATE_WRITE:
		res->delegation_type = FMODE_WRITE|FMODE_READ;
		if (decode_space_limit(xdr, &res->pagemod_limit) < 0)
				return -EIO;
	}
	return decode_ace(xdr, NULL);
}


static void nfs4_handle_setlk_error(struct nfs_server *server, struct nfs4_lock_state *lsp, int new_lock_owner, int error)
{
	switch (error) {
	case -NFS4ERR_ADMIN_REVOKED:
	case -NFS4ERR_EXPIRED:
	case -NFS4ERR_BAD_STATEID:
		lsp->ls_seqid.flags &= ~NFS_SEQID_CONFIRMED;
		if (new_lock_owner != 0 ||
		   test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0)
			nfs4_schedule_stateid_recovery(server, lsp->ls_state);
		break;
	case -NFS4ERR_STALE_STATEID:
		lsp->ls_seqid.flags &= ~NFS_SEQID_CONFIRMED;
		nfs4_schedule_lease_recovery(server->nfs_client);
	}
}


static int decode_layoutcommit(struct xdr_stream *xdr,
			       struct rpc_rqst *req,
			       struct nfs4_layoutcommit_res *res)
{
	__be32 *p;
	__u32 sizechanged;
	int status;

	status = decode_op_hdr(xdr, OP_LAYOUTCOMMIT);
	res->status = status;
	if (status)
		return status;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(!p))
		return -EIO;
	sizechanged = be32_to_cpup(p);

	if (sizechanged) {
		/* throw away new size */
		p = xdr_inline_decode(xdr, 8);
		if (unlikely(!p))
			return -EIO;
	}
	return 0;
}


static void nfs41_sequence_res_init(struct nfs4_sequence_res *res)
{
	res->sr_timestamp = jiffies;
	res->sr_status_flags = 0;
	res->sr_status = 1;
}


static bool nfs_need_update_open_stateid(struct nfs4_state *state,
		const nfs4_stateid *stateid)
{
	if (test_bit(NFS_OPEN_STATE, &state->flags) == 0 ||
	    !nfs4_stateid_match_other(stateid, &state->open_stateid)) {
		if (stateid->seqid == cpu_to_be32(1))
			nfs_state_log_update_open_stateid(state);
		else
			set_bit(NFS_STATE_CHANGE_WAIT, &state->flags);
		return true;
	}

	if (nfs4_stateid_is_newer(stateid, &state->open_stateid)) {
		nfs_state_log_out_of_order_open_stateid(state, stateid);
		return true;
	}
	return false;
}


static int nfs4_xdr_dec_setattr(struct rpc_rqst *rqstp,
				struct xdr_stream *xdr,
				void *data)
{
	struct nfs_setattrres *res = data;
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (status)
		goto out;
	status = decode_sequence(xdr, &res->seq_res, rqstp);
	if (status)
		goto out;
	status = decode_putfh(xdr);
	if (status)
		goto out;
	status = decode_setattr(xdr);
	if (status)
		goto out;
	decode_getfattr_label(xdr, res->fattr, res->label, res->server);
out:
	return status;
}


static int _nfs40_proc_fsid_present(struct inode *inode, const struct cred *cred)
{
	struct nfs_server *server = NFS_SERVER(inode);
	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
	struct rpc_clnt *clnt = server->client;
	struct nfs4_fsid_present_arg args = {
		.fh		= NFS_FH(inode),
		.clientid	= clp->cl_clientid,
		.renew		= 1,		/* append RENEW */
	};
	struct nfs4_fsid_present_res res = {
		.renew		= 1,
	};
	struct rpc_message msg = {
		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_FSID_PRESENT],
		.rpc_argp	= &args,
		.rpc_resp	= &res,
		.rpc_cred	= cred,
	};
	unsigned long now = jiffies;
	int status;

	res.fh = nfs_alloc_fhandle();
	if (res.fh == NULL)
		return -ENOMEM;

	nfs4_init_sequence(&args.seq_args, &res.seq_res, 0, 1);
	status = nfs4_call_sync_sequence(clnt, server, &msg,
						&args.seq_args, &res.seq_res);
	nfs_free_fhandle(res.fh);
	if (status)
		return status;

	do_renew_lease(clp, now);
	return 0;
}


static void nfs4_open_confirm_release(void *calldata)
{
	struct nfs4_opendata *data = calldata;
	struct nfs4_state *state = NULL;

	/* If this request hasn't been cancelled, do nothing */
	if (!data->cancelled)
		goto out_free;
	/* In case of error, no cleanup! */
	if (!data->rpc_done)
		goto out_free;
	state = nfs4_opendata_to_nfs4_state(data);
	if (!IS_ERR(state))
		nfs4_close_state(state, data->o_arg.fmode);
out_free:
	nfs4_opendata_put(data);
}


static fmode_t _nfs4_ctx_to_openmode(const struct nfs_open_context *ctx)
{
	fmode_t ret = ctx->mode & (FMODE_READ|FMODE_WRITE);

	return (ctx->mode & FMODE_EXEC) ? FMODE_READ | ret : ret;
}


static bool nfs4_error_stateid_expired(int err)
{
	switch (err) {
	case -NFS4ERR_DELEG_REVOKED:
	case -NFS4ERR_ADMIN_REVOKED:
	case -NFS4ERR_BAD_STATEID:
	case -NFS4ERR_STALE_STATEID:
	case -NFS4ERR_OLD_STATEID:
	case -NFS4ERR_OPENMODE:
	case -NFS4ERR_EXPIRED:
		return true;
	}
	return false;
}


static int nfs4_proc_async_renew(struct nfs_client *clp, const struct cred *cred, unsigned renew_flags)
{
	struct rpc_message msg = {
		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_RENEW],
		.rpc_argp	= clp,
		.rpc_cred	= cred,
	};
	struct nfs4_renewdata *data;

	if (renew_flags == 0)
		return 0;
	if (!refcount_inc_not_zero(&clp->cl_count))
		return -EIO;
	data = kmalloc(sizeof(*data), GFP_NOFS);
	if (data == NULL) {
		nfs_put_client(clp);
		return -ENOMEM;
	}
	data->client = clp;
	data->timestamp = jiffies;
	return rpc_call_async(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT,
			&nfs4_renew_ops, data);
}


nfs4_layoutcommit_done(struct rpc_task *task, void *calldata)
{
	struct nfs4_layoutcommit_data *data = calldata;
	struct nfs_server *server = NFS_SERVER(data->args.inode);

	if (!nfs41_sequence_done(task, &data->res.seq_res))
		return;

	switch (task->tk_status) { /* Just ignore these failures */
	case -NFS4ERR_DELEG_REVOKED: /* layout was recalled */
	case -NFS4ERR_BADIOMODE:     /* no IOMODE_RW layout for range */
	case -NFS4ERR_BADLAYOUT:     /* no layout */
	case -NFS4ERR_GRACE:	    /* loca_recalim always false */
		task->tk_status = 0;
	case 0:
		break;
	default:
		if (nfs4_async_handle_error(task, server, NULL, NULL) == -EAGAIN) {
			rpc_restart_call_prepare(task);
			return;
		}
	}
}


static int decode_pnfs_layout_types(struct xdr_stream *xdr,
				    struct nfs_fsinfo *fsinfo)
{
	__be32 *p;
	uint32_t i;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(!p))
		return -EIO;
	fsinfo->nlayouttypes = be32_to_cpup(p);

	/* pNFS is not supported by the underlying file system */
	if (fsinfo->nlayouttypes == 0)
		return 0;

	/* Decode and set first layout type, move xdr->p past unused types */
	p = xdr_inline_decode(xdr, fsinfo->nlayouttypes * 4);
	if (unlikely(!p))
		return -EIO;

	/* If we get too many, then just cap it at the max */
	if (fsinfo->nlayouttypes > NFS_MAX_LAYOUT_TYPES) {
		printk(KERN_INFO "NFS: %s: Warning: Too many (%u) pNFS layout types\n",
			__func__, fsinfo->nlayouttypes);
		fsinfo->nlayouttypes = NFS_MAX_LAYOUT_TYPES;
	}

	for(i = 0; i < fsinfo->nlayouttypes; ++i)
		fsinfo->layouttype[i] = be32_to_cpup(p++);
	return 0;
}


static int nfs4_xdr_dec_lock(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
			     void *data)
{
	struct nfs_lock_res *res = data;
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (status)
		goto out;
	status = decode_sequence(xdr, &res->seq_res, rqstp);
	if (status)
		goto out;
	status = decode_putfh(xdr);
	if (status)
		goto out;
	status = decode_lock(xdr, res);
out:
	return status;
}


static void nfs40_clear_delegation_stateid(struct nfs4_state *state)
{
	if (rcu_access_pointer(NFS_I(state->inode)->delegation) != NULL)
		nfs_finish_clear_delegation_stateid(state, NULL);
}


static int _nfs4_lookup_root(struct nfs_server *server, struct nfs_fh *fhandle,
		struct nfs_fsinfo *info)
{
	u32 bitmask[3];
	struct nfs4_lookup_root_arg args = {
		.bitmask = bitmask,
	};
	struct nfs4_lookup_res res = {
		.server = server,
		.fattr = info->fattr,
		.fh = fhandle,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOOKUP_ROOT],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};

	bitmask[0] = nfs4_fattr_bitmap[0];
	bitmask[1] = nfs4_fattr_bitmap[1];
	/*
	 * Process the label in the upcoming getfattr
	 */
	bitmask[2] = nfs4_fattr_bitmap[2] & ~FATTR4_WORD2_SECURITY_LABEL;

	nfs_fattr_init(info->fattr);
	return nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 0);
}


encode_layoutreturn(struct xdr_stream *xdr,
		    const struct nfs4_layoutreturn_args *args,
		    struct compound_hdr *hdr)
{
}


_nfs4_proc_remove(struct inode *dir, const struct qstr *name, u32 ftype)
{
	struct nfs_server *server = NFS_SERVER(dir);
	struct nfs_removeargs args = {
		.fh = NFS_FH(dir),
		.name = *name,
	};
	struct nfs_removeres res = {
		.server = server,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_REMOVE],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};
	unsigned long timestamp = jiffies;
	int status;

	status = nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 1);
	if (status == 0) {
		spin_lock(&dir->i_lock);
		nfs4_update_changeattr_locked(dir, &res.cinfo, timestamp,
					      NFS_INO_INVALID_DATA);
		/* Removing a directory decrements nlink in the parent */
		if (ftype == NF4DIR && dir->i_nlink > 2)
			nfs4_dec_nlink_locked(dir);
		spin_unlock(&dir->i_lock);
	}
	return status;
}


static int nfs4_run_open_task(struct nfs4_opendata *data,
			      struct nfs_open_context *ctx)
{
	struct inode *dir = d_inode(data->dir);
	struct nfs_server *server = NFS_SERVER(dir);
	struct nfs_openargs *o_arg = &data->o_arg;
	struct nfs_openres *o_res = &data->o_res;
	struct rpc_task *task;
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_OPEN],
		.rpc_argp = o_arg,
		.rpc_resp = o_res,
		.rpc_cred = data->owner->so_cred,
	};
	struct rpc_task_setup task_setup_data = {
		.rpc_client = server->client,
		.rpc_message = &msg,
		.callback_ops = &nfs4_open_ops,
		.callback_data = data,
		.workqueue = nfsiod_workqueue,
		.flags = RPC_TASK_ASYNC | RPC_TASK_CRED_NOREF,
	};
	int status;

	kref_get(&data->kref);
	data->rpc_done = false;
	data->rpc_status = 0;
	data->cancelled = false;
	data->is_recover = false;
	if (!ctx) {
		nfs4_init_sequence(&o_arg->seq_args, &o_res->seq_res, 1, 1);
		data->is_recover = true;
		task_setup_data.flags |= RPC_TASK_TIMEOUT;
	} else {
		nfs4_init_sequence(&o_arg->seq_args, &o_res->seq_res, 1, 0);
		pnfs_lgopen_prepare(data, ctx);
	}
	task = rpc_run_task(&task_setup_data);
	if (IS_ERR(task))
		return PTR_ERR(task);
	status = rpc_wait_for_completion_task(task);
	if (status != 0) {
		data->cancelled = true;
		smp_wmb();
	} else
		status = data->rpc_status;
	rpc_put_task(task);

	return status;
}


static int decode_reclaim_complete(struct xdr_stream *xdr, void *dummy)
{
	return decode_op_hdr(xdr, OP_RECLAIM_COMPLETE);
}


static void nfs4_xdr_enc_lookup_root(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const void *data)
{
	const struct nfs4_lookup_root_arg *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putrootfh(xdr, &hdr);
	encode_getfh(xdr, &hdr);
	encode_getfattr(xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
}


static bool nfs_open_stateid_recover_openmode(struct nfs4_state *state)
{
	if (state->n_rdonly && !test_bit(NFS_O_RDONLY_STATE, &state->flags))
		return true;
	if (state->n_wronly && !test_bit(NFS_O_WRONLY_STATE, &state->flags))
		return true;
	if (state->n_rdwr && !test_bit(NFS_O_RDWR_STATE, &state->flags))
		return true;
	return false;
}


static int decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
{
	stateid->type = NFS4_LAYOUT_STATEID_TYPE;
	return decode_stateid(xdr, stateid);
}


static int nfs4_xdr_dec_symlink(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
				void *res)
{
	return nfs4_xdr_dec_create(rqstp, xdr, res);
}


static int _nfs4_do_setattr(struct inode *inode,
			    struct nfs_setattrargs *arg,
			    struct nfs_setattrres *res,
			    const struct cred *cred,
			    struct nfs_open_context *ctx)
{
	struct nfs_server *server = NFS_SERVER(inode);
	struct rpc_message msg = {
		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_SETATTR],
		.rpc_argp	= arg,
		.rpc_resp	= res,
		.rpc_cred	= cred,
	};
	const struct cred *delegation_cred = NULL;
	unsigned long timestamp = jiffies;
	bool truncate;
	int status;

	nfs_fattr_init(res->fattr);

	/* Servers should only apply open mode checks for file size changes */
	truncate = (arg->iap->ia_valid & ATTR_SIZE) ? true : false;
	if (!truncate)
		goto zero_stateid;

	if (nfs4_copy_delegation_stateid(inode, FMODE_WRITE, &arg->stateid, &delegation_cred)) {
		/* Use that stateid */
	} else if (ctx != NULL && ctx->state) {
		struct nfs_lock_context *l_ctx;
		if (!nfs4_valid_open_stateid(ctx->state))
			return -EBADF;
		l_ctx = nfs_get_lock_context(ctx);
		if (IS_ERR(l_ctx))
			return PTR_ERR(l_ctx);
		status = nfs4_select_rw_stateid(ctx->state, FMODE_WRITE, l_ctx,
						&arg->stateid, &delegation_cred);
		nfs_put_lock_context(l_ctx);
		if (status == -EIO)
			return -EBADF;
		else if (status == -EAGAIN)
			goto zero_stateid;
	} else {
zero_stateid:
		nfs4_stateid_copy(&arg->stateid, &zero_stateid);
	}
	if (delegation_cred)
		msg.rpc_cred = delegation_cred;

	status = nfs4_call_sync(server->client, server, &msg, &arg->seq_args, &res->seq_res, 1);

	put_cred(delegation_cred);
	if (status == 0 && ctx != NULL)
		renew_lease(server, timestamp);
	trace_nfs4_setattr(inode, &arg->stateid, status);
	return status;
}


static u32 nfs4_xdr_minorversion(const struct nfs4_sequence_args *args)
{
#if defined(CONFIG_NFS_V4_1)
	struct nfs4_session *session = args->sa_slot->table->session;
	if (session)
		return session->clp->cl_mvops->minor_version;
#endif /* CONFIG_NFS_V4_1 */
	return 0;
}


static void nfs4_xdr_enc_readdir(struct rpc_rqst *req, struct xdr_stream *xdr,
				 const void *data)
{
	const struct nfs4_readdir_arg *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_readdir(xdr, args, req, &hdr);

	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
				args->count, hdr.replen);
	encode_nops(&hdr);
}


static void encode_setclientid_confirm(struct xdr_stream *xdr, const struct nfs4_setclientid_res *arg, struct compound_hdr *hdr)
{
	encode_op_hdr(xdr, OP_SETCLIENTID_CONFIRM,
			decode_setclientid_confirm_maxsz, hdr);
	encode_uint64(xdr, arg->clientid);
	encode_nfs4_verifier(xdr, &arg->confirm);
}


static int _nfs4_proc_lookup(struct rpc_clnt *clnt, struct inode *dir,
		struct dentry *dentry, struct nfs_fh *fhandle,
		struct nfs_fattr *fattr, struct nfs4_label *label)
{
	struct nfs_server *server = NFS_SERVER(dir);
	int		       status;
	struct nfs4_lookup_arg args = {
		.bitmask = server->attr_bitmask,
		.dir_fh = NFS_FH(dir),
		.name = &dentry->d_name,
	};
	struct nfs4_lookup_res res = {
		.server = server,
		.fattr = fattr,
		.label = label,
		.fh = fhandle,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOOKUP],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};
	unsigned short task_flags = 0;

	/* Is this is an attribute revalidation, subject to softreval? */
	if (nfs_lookup_is_soft_revalidate(dentry))
		task_flags |= RPC_TASK_TIMEOUT;

	args.bitmask = nfs4_bitmask(server, label);

	nfs_fattr_init(fattr);

	dprintk("NFS call  lookup %pd2\n", dentry);
	nfs4_init_sequence(&args.seq_args, &res.seq_res, 0, 0);
	status = nfs4_do_call_sync(clnt, server, &msg,
			&args.seq_args, &res.seq_res, task_flags);
	dprintk("NFS reply lookup: %d\n", status);
	return status;
}


int nfs4_buf_to_pages_noslab(const void *buf, size_t buflen,
		struct page **pages)
{
	struct page *newpage, **spages;
	int rc = 0;
	size_t len;
	spages = pages;

	do {
		len = min_t(size_t, PAGE_SIZE, buflen);
		newpage = alloc_page(GFP_KERNEL);

		if (newpage == NULL)
			goto unwind;
		memcpy(page_address(newpage), buf, len);
		buf += len;
		buflen -= len;
		*pages++ = newpage;
		rc++;
	} while (buflen != 0);

	return rc;

unwind:
	for(; rc > 0; rc--)
		__free_page(spages[rc-1]);
	return -ENOMEM;
}


static int nfs4_lock_expired(struct nfs4_state *state, struct file_lock *request)
{
	struct nfs_server *server = NFS_SERVER(state->inode);
	struct nfs4_exception exception = {
		.inode = state->inode,
	};
	int err;

	err = nfs4_set_lock_state(state, request);
	if (err != 0)
		return err;
	if (!recover_lost_locks) {
		set_bit(NFS_LOCK_LOST, &request->fl_u.nfs4_fl.owner->ls_flags);
		return 0;
	}
	do {
		if (test_bit(NFS_DELEGATED_STATE, &state->flags) != 0)
			return 0;
		err = _nfs4_do_setlk(state, F_SETLK, request, NFS_LOCK_EXPIRED);
		switch (err) {
		default:
			goto out;
		case -NFS4ERR_GRACE:
		case -NFS4ERR_DELAY:
			nfs4_handle_exception(server, err, &exception);
			err = 0;
		}
	} while (exception.retry);
out:
	return err;
}


static int nfs4_xdr_dec_sequence(struct rpc_rqst *rqstp,
				 struct xdr_stream *xdr,
				 void *res)
{
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (!status)
		status = decode_sequence(xdr, res, rqstp);
	return status;
}


int nfs4_proc_destroy_session(struct nfs4_session *session,
		const struct cred *cred)
{
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_DESTROY_SESSION],
		.rpc_argp = session,
		.rpc_cred = cred,
	};
	int status = 0;

	dprintk("--> nfs4_proc_destroy_session\n");

	/* session is still being setup */
	if (!test_and_clear_bit(NFS4_SESSION_ESTABLISHED, &session->session_state))
		return 0;

	status = rpc_call_sync(session->clp->cl_rpcclient, &msg,
			       RPC_TASK_TIMEOUT | RPC_TASK_NO_ROUND_ROBIN);
	trace_nfs4_destroy_session(session->clp, status);

	if (status)
		dprintk("NFS: Got error %d from the server on DESTROY_SESSION. "
			"Session has been destroyed regardless...\n", status);

	dprintk("<-- nfs4_proc_destroy_session\n");
	return status;
}


static int _nfs4_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
				struct nfs_fattr *fattr, struct nfs4_label *label,
				struct inode *inode)
{
	__u32 bitmask[NFS4_BITMASK_SZ];
	struct nfs4_getattr_arg args = {
		.fh = fhandle,
		.bitmask = bitmask,
	};
	struct nfs4_getattr_res res = {
		.fattr = fattr,
		.label = label,
		.server = server,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_GETATTR],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};
	unsigned short task_flags = 0;

	/* Is this is an attribute revalidation, subject to softreval? */
	if (inode && (server->flags & NFS_MOUNT_SOFTREVAL))
		task_flags |= RPC_TASK_TIMEOUT;

	nfs4_bitmap_copy_adjust(bitmask, nfs4_bitmask(server, label), inode);

	nfs_fattr_init(fattr);
	nfs4_init_sequence(&args.seq_args, &res.seq_res, 0, 0);
	return nfs4_do_call_sync(server->client, server, &msg,
			&args.seq_args, &res.seq_res, task_flags);
}


static inline void encode_claim_delegate_cur(struct xdr_stream *xdr, const struct qstr *name, const nfs4_stateid *stateid)
{
	__be32 *p;

	p = reserve_space(xdr, 4);
	*p = cpu_to_be32(NFS4_OPEN_CLAIM_DELEGATE_CUR);
	encode_nfs4_stateid(xdr, stateid);
	encode_string(xdr, name->len, name->name);
}


nfs4_label_release_security(struct nfs4_label *label)
{
	if (label)
		security_release_secctx(label->label, label->len);
}


static int nfs4_do_open_reclaim(struct nfs_open_context *ctx, struct nfs4_state *state)
{
	struct nfs_server *server = NFS_SERVER(state->inode);
	struct nfs4_exception exception = { };
	int err;
	do {
		err = _nfs4_do_open_reclaim(ctx, state);
		trace_nfs4_open_reclaim(ctx, 0, err);
		if (nfs4_clear_cap_atomic_open_v1(server, err, &exception))
			continue;
		if (err != -NFS4ERR_DELAY)
			break;
		nfs4_handle_exception(server, err, &exception);
	} while (exception.retry);
	return err;
}


nfs4_wait_on_layoutreturn(struct inode *inode, struct rpc_task *task)
{
	if (inode == NULL || !nfs_have_layout(inode))
		return false;

	return pnfs_wait_on_layoutreturn(inode, task);
}


static int decode_statfs(struct xdr_stream *xdr, struct nfs_fsstat *fsstat)
{
	unsigned int savep;
	uint32_t attrlen, bitmap[3] = {0};
	int status;

	if ((status = decode_op_hdr(xdr, OP_GETATTR)) != 0)
		goto xdr_error;
	if ((status = decode_attr_bitmap(xdr, bitmap)) != 0)
		goto xdr_error;
	if ((status = decode_attr_length(xdr, &attrlen, &savep)) != 0)
		goto xdr_error;

	if ((status = decode_attr_files_avail(xdr, bitmap, &fsstat->afiles)) != 0)
		goto xdr_error;
	if ((status = decode_attr_files_free(xdr, bitmap, &fsstat->ffiles)) != 0)
		goto xdr_error;
	if ((status = decode_attr_files_total(xdr, bitmap, &fsstat->tfiles)) != 0)
		goto xdr_error;

	status = -EIO;
	if (unlikely(bitmap[0]))
		goto xdr_error;

	if ((status = decode_attr_space_avail(xdr, bitmap, &fsstat->abytes)) != 0)
		goto xdr_error;
	if ((status = decode_attr_space_free(xdr, bitmap, &fsstat->fbytes)) != 0)
		goto xdr_error;
	if ((status = decode_attr_space_total(xdr, bitmap, &fsstat->tbytes)) != 0)
		goto xdr_error;

	status = verify_attr_len(xdr, savep, attrlen);
xdr_error:
	dprintk("%s: xdr returned %d!\n", __func__, -status);
	return status;
}


static void nfs4_slot_sequence_record_sent(struct nfs4_slot *slot,
		u32 seqnr)
{
	if ((s32)(seqnr - slot->seq_nr_highest_sent) > 0)
		slot->seq_nr_highest_sent = seqnr;
}


static int decode_attr_maxname(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *maxname)
{
	__be32 *p;
	int status = 0;

	*maxname = 1024;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXNAME - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_MAXNAME)) {
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(!p))
			return -EIO;
		*maxname = be32_to_cpup(p);
		bitmap[0] &= ~FATTR4_WORD0_MAXNAME;
	}
	dprintk("%s: maxname=%u\n", __func__, *maxname);
	return status;
}


static bool nfs4_write_stateid_changed(struct rpc_task *task,
		struct nfs_pgio_args *args)
{

	if (!nfs4_error_stateid_expired(task->tk_status) ||
		nfs4_stateid_is_current(&args->stateid,
				args->context,
				args->lock_context,
				FMODE_WRITE))
		return false;
	rpc_restart_call_prepare(task);
	return true;
}


static void nfs4_proc_write_setup(struct nfs_pgio_header *hdr,
				  struct rpc_message *msg,
				  struct rpc_clnt **clnt)
{
	struct nfs_server *server = NFS_SERVER(hdr->inode);

	if (!nfs4_write_need_cache_consistency_data(hdr)) {
		hdr->args.bitmask = NULL;
		hdr->res.fattr = NULL;
	} else
		hdr->args.bitmask = server->cache_consistency_bitmask;

	if (!hdr->pgio_done_cb)
		hdr->pgio_done_cb = nfs4_write_done_cb;
	hdr->res.server = server;
	hdr->timestamp   = jiffies;

	msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_WRITE];
	nfs4_init_sequence(&hdr->args.seq_args, &hdr->res.seq_res, 0, 0);
	nfs4_state_protect_write(server->nfs_client, clnt, msg, hdr);
}


_nfs4_proc_getdeviceinfo(struct nfs_server *server,
		struct pnfs_device *pdev,
		const struct cred *cred)
{
	struct nfs4_getdeviceinfo_args args = {
		.pdev = pdev,
		.notify_types = NOTIFY_DEVICEID4_CHANGE |
			NOTIFY_DEVICEID4_DELETE,
	};
	struct nfs4_getdeviceinfo_res res = {
		.pdev = pdev,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_GETDEVICEINFO],
		.rpc_argp = &args,
		.rpc_resp = &res,
		.rpc_cred = cred,
	};
	int status;

	dprintk("--> %s\n", __func__);
	status = nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 0);
	if (res.notification & ~args.notify_types)
		dprintk("%s: unsupported notification\n", __func__);
	if (res.notification != args.notify_types)
		pdev->nocache = 1;

	dprintk("<-- %s status=%d\n", __func__, status);

	return status;
}


decode_restorefh(struct xdr_stream *xdr)
{
	return decode_op_hdr(xdr, OP_RESTOREFH);
}


static int nfs4_xdr_dec_rename(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
			       void *data)
{
	struct nfs_renameres *res = data;
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (status)
		goto out;
	status = decode_sequence(xdr, &res->seq_res, rqstp);
	if (status)
		goto out;
	status = decode_putfh(xdr);
	if (status)
		goto out;
	status = decode_savefh(xdr);
	if (status)
		goto out;
	status = decode_putfh(xdr);
	if (status)
		goto out;
	status = decode_rename(xdr, &res->old_cinfo, &res->new_cinfo);
out:
	return status;
}


int nfs4_proc_commit(struct file *dst, __u64 offset, __u32 count, struct nfs_commitres *res)
{
	struct nfs_commitargs args = {
		.offset = offset,
		.count = count,
	};
	struct nfs_server *dst_server = NFS_SERVER(file_inode(dst));
	struct nfs4_exception exception = { };
	int status;

	do {
		status = _nfs4_proc_commit(dst, &args, res);
		status = nfs4_handle_exception(dst_server, status, &exception);
	} while (exception.retry);

	return status;
}


nfs4_label_release_security(struct nfs4_label *label)
{ return; }


static void encode_create(struct xdr_stream *xdr, const struct nfs4_create_arg *create, struct compound_hdr *hdr)
{
	__be32 *p;

	encode_op_hdr(xdr, OP_CREATE, decode_create_maxsz, hdr);
	encode_uint32(xdr, create->ftype);

	switch (create->ftype) {
	case NF4LNK:
		p = reserve_space(xdr, 4);
		*p = cpu_to_be32(create->u.symlink.len);
		xdr_write_pages(xdr, create->u.symlink.pages, 0,
				create->u.symlink.len);
		xdr->buf->flags |= XDRBUF_WRITE;
		break;

	case NF4BLK: case NF4CHR:
		p = reserve_space(xdr, 8);
		*p++ = cpu_to_be32(create->u.device.specdata1);
		*p = cpu_to_be32(create->u.device.specdata2);
		break;

	default:
		break;
	}

	encode_string(xdr, create->name->len, create->name->name);
	encode_attrs(xdr, create->attrs, create->label, &create->umask,
			create->server, create->server->attr_bitmask);
}


static int decode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
{
	int retval;

	__decode_op_hdr(xdr, expected, &retval);
	return retval;
}


static int nfs4_xattr_get_nfs4_user(const struct xattr_handler *handler,
				    struct dentry *unused, struct inode *inode,
				    const char *key, void *buf, size_t buflen)
{
	struct nfs_access_entry cache;
	ssize_t ret;

	if (!nfs_server_capable(inode, NFS_CAP_XATTR))
		return -EOPNOTSUPP;

	if (!nfs_access_get_cached(inode, current_cred(), &cache, true)) {
		if (!(cache.mask & NFS_ACCESS_XAREAD))
			return -EACCES;
	}

	ret = nfs_revalidate_inode(NFS_SERVER(inode), inode);
	if (ret)
		return ret;

	ret = nfs4_xattr_cache_get(inode, key, buf, buflen);
	if (ret >= 0 || (ret < 0 && ret != -ENOENT))
		return ret;

	ret = nfs42_proc_getxattr(inode, key, buf, buflen);

	return ret;
}


static int can_open_cached(struct nfs4_state *state, fmode_t mode,
		int open_mode, enum open_claim_type4 claim)
{
	int ret = 0;

	if (open_mode & (O_EXCL|O_TRUNC))
		goto out;
	switch (claim) {
	case NFS4_OPEN_CLAIM_NULL:
	case NFS4_OPEN_CLAIM_FH:
		goto out;
	default:
		break;
	}
	switch (mode & (FMODE_READ|FMODE_WRITE)) {
		case FMODE_READ:
			ret |= test_bit(NFS_O_RDONLY_STATE, &state->flags) != 0
				&& state->n_rdonly != 0;
			break;
		case FMODE_WRITE:
			ret |= test_bit(NFS_O_WRONLY_STATE, &state->flags) != 0
				&& state->n_wronly != 0;
			break;
		case FMODE_READ|FMODE_WRITE:
			ret |= test_bit(NFS_O_RDWR_STATE, &state->flags) != 0
				&& state->n_rdwr != 0;
	}
out:
	return ret;
}


static void nfs4_xdr_enc_setattr(struct rpc_rqst *req, struct xdr_stream *xdr,
				 const void *data)
{
	const struct nfs_setattrargs *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_setattr(xdr, args, args->server, &hdr);
	encode_getfattr(xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
}


static int nfs4_xattr_get_nfs4_label(const struct xattr_handler *handler,
				     struct dentry *unused, struct inode *inode,
				     const char *key, void *buf, size_t buflen)
{
	if (security_ismaclabel(key))
		return nfs4_get_security_label(inode, buf, buflen);
	return -EOPNOTSUPP;
}


static void nfs4_xdr_enc_pathconf(struct rpc_rqst *req, struct xdr_stream *xdr,
				  const void *data)
{
	const struct nfs4_pathconf_arg *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_getattr(xdr, nfs4_pathconf_bitmap, args->bitmask,
			ARRAY_SIZE(nfs4_pathconf_bitmap), &hdr);
	encode_nops(&hdr);
}


static int decode_attr_error(struct xdr_stream *xdr, uint32_t *bitmap, int32_t *res)
{
	__be32 *p;

	if (unlikely(bitmap[0] & (FATTR4_WORD0_RDATTR_ERROR - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_RDATTR_ERROR)) {
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(!p))
			return -EIO;
		bitmap[0] &= ~FATTR4_WORD0_RDATTR_ERROR;
		*res = -be32_to_cpup(p);
	}
	return 0;
}


static int _nfs4_proc_lookupp(struct inode *inode,
		struct nfs_fh *fhandle, struct nfs_fattr *fattr,
		struct nfs4_label *label)
{
	struct rpc_clnt *clnt = NFS_CLIENT(inode);
	struct nfs_server *server = NFS_SERVER(inode);
	int		       status;
	struct nfs4_lookupp_arg args = {
		.bitmask = server->attr_bitmask,
		.fh = NFS_FH(inode),
	};
	struct nfs4_lookupp_res res = {
		.server = server,
		.fattr = fattr,
		.label = label,
		.fh = fhandle,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOOKUPP],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};

	args.bitmask = nfs4_bitmask(server, label);

	nfs_fattr_init(fattr);

	dprintk("NFS call  lookupp ino=0x%lx\n", inode->i_ino);
	status = nfs4_call_sync(clnt, server, &msg, &args.seq_args,
				&res.seq_res, 0);
	dprintk("NFS reply lookupp: %d\n", status);
	return status;
}


static inline uint64_t nfs4_lock_length(struct file_lock *fl)
{
	if (fl->fl_end == OFFSET_MAX)
		return ~(uint64_t)0;
	return fl->fl_end - fl->fl_start + 1;
}


static int nfs4_call_sync_sequence(struct rpc_clnt *clnt,
				   struct nfs_server *server,
				   struct rpc_message *msg,
				   struct nfs4_sequence_args *args,
				   struct nfs4_sequence_res *res)
{
	return nfs4_do_call_sync(clnt, server, msg, args, res, 0);
}


nfs4_update_changeattr_locked(struct inode *inode,
		struct nfs4_change_info *cinfo,
		unsigned long timestamp, unsigned long cache_validity)
{
	struct nfs_inode *nfsi = NFS_I(inode);

	nfsi->cache_validity |= NFS_INO_INVALID_CTIME
		| NFS_INO_INVALID_MTIME
		| cache_validity;

	if (cinfo->atomic && cinfo->before == inode_peek_iversion_raw(inode)) {
		nfsi->cache_validity &= ~NFS_INO_REVAL_PAGECACHE;
		nfsi->attrtimeo_timestamp = jiffies;
	} else {
		if (S_ISDIR(inode->i_mode)) {
			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
			nfs_force_lookup_revalidate(inode);
		} else {
			if (!NFS_PROTO(inode)->have_delegation(inode,
							       FMODE_READ))
				nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE;
		}

		if (cinfo->before != inode_peek_iversion_raw(inode))
			nfsi->cache_validity |= NFS_INO_INVALID_ACCESS |
						NFS_INO_INVALID_ACL |
						NFS_INO_INVALID_XATTR;
	}
	inode_set_iversion_raw(inode, cinfo->after);
	nfsi->read_cache_jiffies = timestamp;
	nfsi->attr_gencount = nfs_inc_attr_generation_counter();
	nfsi->cache_validity &= ~NFS_INO_INVALID_CHANGE;

	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
		nfs_fscache_invalidate(inode);
}


static int nfs4_write_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
{
	if (!nfs4_sequence_done(task, &hdr->res.seq_res))
		return -EAGAIN;
	if (nfs4_write_stateid_changed(task, &hdr->args))
		return -EAGAIN;
	return hdr->pgio_done_cb ? hdr->pgio_done_cb(task, hdr) :
		nfs4_write_done_cb(task, hdr);
}


static int decode_write_verifier(struct xdr_stream *xdr, struct nfs_write_verifier *verifier)
{
	return decode_opaque_fixed(xdr, verifier->data, NFS4_VERIFIER_SIZE);
}


static bool nfs4_update_lock_stateid(struct nfs4_lock_state *lsp,
		const nfs4_stateid *stateid)
{
	struct nfs4_state *state = lsp->ls_state;
	bool ret = false;

	spin_lock(&state->state_lock);
	if (!nfs4_stateid_match_other(stateid, &lsp->ls_stateid))
		goto out_noupdate;
	if (!nfs4_stateid_is_newer(stateid, &lsp->ls_stateid))
		goto out_noupdate;
	nfs4_stateid_copy(&lsp->ls_stateid, stateid);
	ret = true;
out_noupdate:
	spin_unlock(&state->state_lock);
	return ret;
}


int nfs4_proc_delegreturn(struct inode *inode, const struct cred *cred, const nfs4_stateid *stateid, int issync)
{
	struct nfs_server *server = NFS_SERVER(inode);
	struct nfs4_exception exception = { };
	int err;
	do {
		err = _nfs4_proc_delegreturn(inode, cred, stateid, issync);
		trace_nfs4_delegreturn(inode, stateid, err);
		switch (err) {
			case -NFS4ERR_STALE_STATEID:
			case -NFS4ERR_EXPIRED:
			case 0:
				return 0;
		}
		err = nfs4_handle_exception(server, err, &exception);
	} while (exception.retry);
	return err;
}


static int decode_lock(struct xdr_stream *xdr, struct nfs_lock_res *res)
{
	int status;

	status = decode_op_hdr(xdr, OP_LOCK);
	if (status == -EIO)
		goto out;
	if (status == 0) {
		status = decode_lock_stateid(xdr, &res->stateid);
		if (unlikely(status))
			goto out;
	} else if (status == -NFS4ERR_DENIED)
		status = decode_lock_denied(xdr, NULL);
	if (res->open_seqid != NULL)
		nfs_increment_open_seqid(status, res->open_seqid);
	nfs_increment_lock_seqid(status, res->lock_seqid);
out:
	return status;
}


static void nfs_resync_open_stateid_locked(struct nfs4_state *state)
{
	if (!(state->n_wronly || state->n_rdonly || state->n_rdwr))
		return;
	if (state->n_wronly)
		set_bit(NFS_O_WRONLY_STATE, &state->flags);
	if (state->n_rdonly)
		set_bit(NFS_O_RDONLY_STATE, &state->flags);
	if (state->n_rdwr)
		set_bit(NFS_O_RDWR_STATE, &state->flags);
	set_bit(NFS_OPEN_STATE, &state->flags);
}


nfs4_opendata_find_nfs4_state(struct nfs4_opendata *data)
{
	struct nfs4_state *state;
	struct inode *inode;

	inode = nfs4_opendata_get_inode(data);
	if (IS_ERR(inode))
		return ERR_CAST(inode);
	if (data->state != NULL && data->state->inode == inode) {
		state = data->state;
		refcount_inc(&state->count);
	} else
		state = nfs4_get_open_state(inode, data->owner);
	iput(inode);
	if (state == NULL)
		state = ERR_PTR(-ENOMEM);
	return state;
}


static void nfs4_layoutget_done(struct rpc_task *task, void *calldata)
{
	struct nfs4_layoutget *lgp = calldata;

	dprintk("--> %s\n", __func__);
	nfs41_sequence_process(task, &lgp->res.seq_res);
	dprintk("<-- %s\n", __func__);
}


static void nfs4_xdr_enc_remove(struct rpc_rqst *req, struct xdr_stream *xdr,
				const void *data)
{
	const struct nfs_removeargs *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_remove(xdr, &args->name, &hdr);
	encode_nops(&hdr);
}


static void encode_close(struct xdr_stream *xdr, const struct nfs_closeargs *arg, struct compound_hdr *hdr)
{
	encode_op_hdr(xdr, OP_CLOSE, decode_close_maxsz, hdr);
	encode_nfs4_seqid(xdr, arg->seqid);
	encode_nfs4_stateid(xdr, &arg->stateid);
}


static int decode_attr_type(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *type)
{
	__be32 *p;
	int ret = 0;

	*type = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_TYPE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_TYPE)) {
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(!p))
			return -EIO;
		*type = be32_to_cpup(p);
		if (*type < NF4REG || *type > NF4NAMEDATTR) {
			dprintk("%s: bad type %d\n", __func__, *type);
			return -EIO;
		}
		bitmap[0] &= ~FATTR4_WORD0_TYPE;
		ret = NFS_ATTR_FATTR_TYPE;
	}
	dprintk("%s: type=0%o\n", __func__, nfs_type2fmt[*type]);
	return ret;
}


nfs41_same_server_scope(struct nfs41_server_scope *a,
			struct nfs41_server_scope *b)
{
	if (a->server_scope_sz != b->server_scope_sz)
		return false;
	return memcmp(a->server_scope, b->server_scope, a->server_scope_sz) == 0;
}


static int decode_chan_attrs(struct xdr_stream *xdr,
			     struct nfs4_channel_attrs *attrs)
{
	__be32 *p;
	u32 nr_attrs, val;

	p = xdr_inline_decode(xdr, 28);
	if (unlikely(!p))
		return -EIO;
	val = be32_to_cpup(p++);	/* headerpadsz */
	if (val)
		return -EINVAL;		/* no support for header padding yet */
	attrs->max_rqst_sz = be32_to_cpup(p++);
	attrs->max_resp_sz = be32_to_cpup(p++);
	attrs->max_resp_sz_cached = be32_to_cpup(p++);
	attrs->max_ops = be32_to_cpup(p++);
	attrs->max_reqs = be32_to_cpup(p++);
	nr_attrs = be32_to_cpup(p);
	if (unlikely(nr_attrs > 1)) {
		printk(KERN_WARNING "NFS: %s: Invalid rdma channel attrs "
			"count %u\n", __func__, nr_attrs);
		return -EINVAL;
	}
	if (nr_attrs == 1) {
		p = xdr_inline_decode(xdr, 4); /* skip rdma_attrs */
		if (unlikely(!p))
			return -EIO;
	}
	return 0;
}


int nfs4_proc_bind_conn_to_session(struct nfs_client *clp, const struct cred *cred)
{
	struct rpc_bind_conn_calldata data = {
		.clp = clp,
		.cred = cred,
	};
	return rpc_clnt_iterate_for_each_xprt(clp->cl_rpcclient,
			nfs4_proc_bind_conn_to_session_callback, &data);
}


nfs4_opendata_to_nfs4_state(struct nfs4_opendata *data)
{
	struct nfs4_state *ret;

	if (data->o_arg.claim == NFS4_OPEN_CLAIM_PREVIOUS)
		ret =_nfs4_opendata_reclaim_to_nfs4_state(data);
	else
		ret = _nfs4_opendata_to_nfs4_state(data);
	nfs4_sequence_free_slot(&data->o_res.seq_res);
	return ret;
}


static void nfs4_delegreturn_prepare(struct rpc_task *task, void *data)
{
	struct nfs4_delegreturndata *d_data;
	struct pnfs_layout_hdr *lo;

	d_data = (struct nfs4_delegreturndata *)data;

	if (!d_data->lr.roc && nfs4_wait_on_layoutreturn(d_data->inode, task)) {
		nfs4_sequence_done(task, &d_data->res.seq_res);
		return;
	}

	lo = d_data->args.lr_args ? d_data->args.lr_args->layout : NULL;
	if (lo && !pnfs_layout_is_valid(lo)) {
		d_data->args.lr_args = NULL;
		d_data->res.lr_res = NULL;
	}

	nfs4_setup_sequence(d_data->res.server->nfs_client,
			&d_data->args.seq_args,
			&d_data->res.seq_res,
			task);
}


static int nfs41_proc_async_sequence(struct nfs_client *clp, const struct cred *cred, unsigned renew_flags)
{
	struct rpc_task *task;
	int ret = 0;

	if ((renew_flags & NFS4_RENEW_TIMEOUT) == 0)
		return -EAGAIN;
	task = _nfs41_proc_sequence(clp, cred, NULL, false);
	if (IS_ERR(task))
		ret = PTR_ERR(task);
	else
		rpc_put_task_async(task);
	dprintk("<-- %s status=%d\n", __func__, ret);
	return ret;
}


static void nfs4_proc_rename_rpc_prepare(struct rpc_task *task, struct nfs_renamedata *data)
{
	nfs4_setup_sequence(NFS_SERVER(data->old_dir)->nfs_client,
			&data->args.seq_args,
			&data->res.seq_res,
			task);
}


static int decode_open(struct xdr_stream *xdr, struct nfs_openres *res)
{
	__be32 *p;
	uint32_t savewords, bmlen, i;
	int status;

	if (!__decode_op_hdr(xdr, OP_OPEN, &status))
		return status;
	nfs_increment_open_seqid(status, res->seqid);
	if (status)
		return status;
	status = decode_open_stateid(xdr, &res->stateid);
	if (unlikely(status))
		return status;

	decode_change_info(xdr, &res->cinfo);

	p = xdr_inline_decode(xdr, 8);
	if (unlikely(!p))
		return -EIO;
	res->rflags = be32_to_cpup(p++);
	bmlen = be32_to_cpup(p);
	if (bmlen > 10)
		goto xdr_error;

	p = xdr_inline_decode(xdr, bmlen << 2);
	if (unlikely(!p))
		return -EIO;
	savewords = min_t(uint32_t, bmlen, NFS4_BITMAP_SIZE);
	for (i = 0; i < savewords; ++i)
		res->attrset[i] = be32_to_cpup(p++);
	for (; i < NFS4_BITMAP_SIZE; i++)
		res->attrset[i] = 0;

	return decode_delegation(xdr, res);
xdr_error:
	dprintk("%s: Bitmap too large! Length = %u\n", __func__, bmlen);
	return -EIO;
}


static void encode_nfs4_stateid(struct xdr_stream *xdr, const nfs4_stateid *stateid)
{
	encode_opaque_fixed(xdr, stateid, NFS4_STATEID_SIZE);
}


static unsigned nfs4_exclusive_attrset(struct nfs4_opendata *opendata,
				struct iattr *sattr, struct nfs4_label **label)
{
	const __u32 *bitmask = opendata->o_arg.server->exclcreat_bitmask;
	__u32 attrset[3];
	unsigned ret;
	unsigned i;

	for (i = 0; i < ARRAY_SIZE(attrset); i++) {
		attrset[i] = opendata->o_res.attrset[i];
		if (opendata->o_arg.createmode == NFS4_CREATE_EXCLUSIVE4_1)
			attrset[i] &= ~bitmask[i];
	}

	ret = (opendata->o_arg.createmode == NFS4_CREATE_EXCLUSIVE) ?
		sattr->ia_valid : 0;

	if ((attrset[1] & (FATTR4_WORD1_TIME_ACCESS|FATTR4_WORD1_TIME_ACCESS_SET))) {
		if (sattr->ia_valid & ATTR_ATIME_SET)
			ret |= ATTR_ATIME_SET;
		else
			ret |= ATTR_ATIME;
	}

	if ((attrset[1] & (FATTR4_WORD1_TIME_MODIFY|FATTR4_WORD1_TIME_MODIFY_SET))) {
		if (sattr->ia_valid & ATTR_MTIME_SET)
			ret |= ATTR_MTIME_SET;
		else
			ret |= ATTR_MTIME;
	}

	if (!(attrset[2] & FATTR4_WORD2_SECURITY_LABEL))
		*label = NULL;
	return ret;
}


static int decode_attr_maxwrite(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 1024;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXWRITE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_MAXWRITE)) {
		uint64_t maxwrite;
		p = xdr_inline_decode(xdr, 8);
		if (unlikely(!p))
			return -EIO;
		xdr_decode_hyper(p, &maxwrite);
		if (maxwrite > 0x7FFFFFFF)
			maxwrite = 0x7FFFFFFF;
		*res = (uint32_t)maxwrite;
		bitmap[0] &= ~FATTR4_WORD0_MAXWRITE;
	}
	dprintk("%s: maxwrite=%lu\n", __func__, (unsigned long)*res);
	return status;
}


static void encode_opentype(struct xdr_stream *xdr, const struct nfs_openargs *arg)
{
	__be32 *p;

	p = reserve_space(xdr, 4);
	switch (arg->open_flags & O_CREAT) {
	case 0:
		*p = cpu_to_be32(NFS4_OPEN_NOCREATE);
		break;
	default:
		*p = cpu_to_be32(NFS4_OPEN_CREATE);
		encode_createmode(xdr, arg);
	}
}


static int decode_getfattr_label(struct xdr_stream *xdr, struct nfs_fattr *fattr,
		struct nfs4_label *label, const struct nfs_server *server)
{
	return decode_getfattr_generic(xdr, fattr, NULL, NULL, label, server);
}


static size_t mask_bitmap4(const __u32 *bitmap, const __u32 *mask,
		__u32 *res, size_t len)
{
	size_t i;
	__u32 tmp;

	while (len > 0 && (bitmap[len-1] == 0 || mask[len-1] == 0))
		len--;
	for (i = len; i-- > 0;) {
		tmp = bitmap[i] & mask[i];
		res[i] = tmp;
	}
	return len;
}


nfs4_retry_setlk(struct nfs4_state *state, int cmd, struct file_lock *request)
{
	return nfs4_retry_setlk_simple(state, cmd, request);
}


static int decode_exchange_id(struct xdr_stream *xdr,
			      struct nfs41_exchange_id_res *res)
{
	__be32 *p;
	uint32_t dummy;
	char *dummy_str;
	int status;
	uint32_t impl_id_count;

	status = decode_op_hdr(xdr, OP_EXCHANGE_ID);
	if (status)
		return status;

	p = xdr_inline_decode(xdr, 8);
	if (unlikely(!p))
		return -EIO;
	xdr_decode_hyper(p, &res->clientid);
	p = xdr_inline_decode(xdr, 12);
	if (unlikely(!p))
		return -EIO;
	res->seqid = be32_to_cpup(p++);
	res->flags = be32_to_cpup(p++);

	res->state_protect.how = be32_to_cpup(p);
	switch (res->state_protect.how) {
	case SP4_NONE:
		break;
	case SP4_MACH_CRED:
		status = decode_op_map(xdr, &res->state_protect.enforce);
		if (status)
			return status;
		status = decode_op_map(xdr, &res->state_protect.allow);
		if (status)
			return status;
		break;
	default:
		WARN_ON_ONCE(1);
		return -EIO;
	}

	/* server_owner4.so_minor_id */
	p = xdr_inline_decode(xdr, 8);
	if (unlikely(!p))
		return -EIO;
	p = xdr_decode_hyper(p, &res->server_owner->minor_id);

	/* server_owner4.so_major_id */
	status = decode_opaque_inline(xdr, &dummy, &dummy_str);
	if (unlikely(status))
		return status;
	memcpy(res->server_owner->major_id, dummy_str, dummy);
	res->server_owner->major_id_sz = dummy;

	/* server_scope4 */
	status = decode_opaque_inline(xdr, &dummy, &dummy_str);
	if (unlikely(status))
		return status;
	memcpy(res->server_scope->server_scope, dummy_str, dummy);
	res->server_scope->server_scope_sz = dummy;

	/* Implementation Id */
	p = xdr_inline_decode(xdr, 4);
	if (unlikely(!p))
		return -EIO;
	impl_id_count = be32_to_cpup(p++);

	if (impl_id_count) {
		/* nii_domain */
		status = decode_opaque_inline(xdr, &dummy, &dummy_str);
		if (unlikely(status))
			return status;
		memcpy(res->impl_id->domain, dummy_str, dummy);

		/* nii_name */
		status = decode_opaque_inline(xdr, &dummy, &dummy_str);
		if (unlikely(status))
			return status;
		memcpy(res->impl_id->name, dummy_str, dummy);

		/* nii_date */
		p = xdr_inline_decode(xdr, 12);
		if (unlikely(!p))
			return -EIO;
		p = xdr_decode_hyper(p, &res->impl_id->date.seconds);
		res->impl_id->date.nseconds = be32_to_cpup(p);

		/* if there's more than one entry, ignore the rest */
	}
	return 0;
}


static void nfs4_xdr_enc_close(struct rpc_rqst *req, struct xdr_stream *xdr,
			       const void *data)
{
	const struct nfs_closeargs *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	if (args->lr_args)
		encode_layoutreturn(xdr, args->lr_args, &hdr);
	if (args->bitmask != NULL)
		encode_getfattr(xdr, args->bitmask, &hdr);
	encode_close(xdr, args, &hdr);
	encode_nops(&hdr);
}


static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t buflen)
{
	struct page **pages;
	struct nfs_getaclargs args = {
		.fh = NFS_FH(inode),
		.acl_len = buflen,
	};
	struct nfs_getaclres res = {
		.acl_len = buflen,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_GETACL],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};
	unsigned int npages;
	int ret = -ENOMEM, i;
	struct nfs_server *server = NFS_SERVER(inode);

	if (buflen == 0)
		buflen = server->rsize;

	npages = DIV_ROUND_UP(buflen, PAGE_SIZE) + 1;
	pages = kmalloc_array(npages, sizeof(struct page *), GFP_NOFS);
	if (!pages)
		return -ENOMEM;

	args.acl_pages = pages;

	for (i = 0; i < npages; i++) {
		pages[i] = alloc_page(GFP_KERNEL);
		if (!pages[i])
			goto out_free;
	}

	/* for decoding across pages */
	res.acl_scratch = alloc_page(GFP_KERNEL);
	if (!res.acl_scratch)
		goto out_free;

	args.acl_len = npages * PAGE_SIZE;

	dprintk("%s  buf %p buflen %zu npages %d args.acl_len %zu\n",
		__func__, buf, buflen, npages, args.acl_len);
	ret = nfs4_call_sync(NFS_SERVER(inode)->client, NFS_SERVER(inode),
			     &msg, &args.seq_args, &res.seq_res, 0);
	if (ret)
		goto out_free;

	/* Handle the case where the passed-in buffer is too short */
	if (res.acl_flags & NFS4_ACL_TRUNC) {
		/* Did the user only issue a request for the acl length? */
		if (buf == NULL)
			goto out_ok;
		ret = -ERANGE;
		goto out_free;
	}
	nfs4_write_cached_acl(inode, pages, res.acl_data_offset, res.acl_len);
	if (buf) {
		if (res.acl_len > buflen) {
			ret = -ERANGE;
			goto out_free;
		}
		_copy_from_pages(buf, pages, res.acl_data_offset, res.acl_len);
	}
out_ok:
	ret = res.acl_len;
out_free:
	for (i = 0; i < npages; i++)
		if (pages[i])
			__free_page(pages[i]);
	if (res.acl_scratch)
		__free_page(res.acl_scratch);
	kfree(pages);
	return ret;
}


static void nfs4_xdr_enc_fsinfo(struct rpc_rqst *req, struct xdr_stream *xdr,
				const void *data)
{
	const struct nfs4_fsinfo_arg *args = data;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_sequence(xdr, &args->seq_args, &hdr);
	encode_putfh(xdr, args->fh, &hdr);
	encode_fsinfo(xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
}


static struct nfs4_state *nfs4_do_open(struct inode *dir,
					struct nfs_open_context *ctx,
					int flags,
					struct iattr *sattr,
					struct nfs4_label *label,
					int *opened)
{
	struct nfs_server *server = NFS_SERVER(dir);
	struct nfs4_exception exception = {
		.interruptible = true,
	};
	struct nfs4_state *res;
	struct nfs4_open_createattrs c = {
		.label = label,
		.sattr = sattr,
		.verf = {
			[0] = (__u32)jiffies,
			[1] = (__u32)current->pid,
		},
	};
	int status;

	do {
		status = _nfs4_do_open(dir, ctx, flags, &c, opened);
		res = ctx->state;
		trace_nfs4_open_file(ctx, flags, status);
		if (status == 0)
			break;
		/* NOTE: BAD_SEQID means the server and client disagree about the
		 * book-keeping w.r.t. state-changing operations
		 * (OPEN/CLOSE/LOCK/LOCKU...)
		 * It is actually a sign of a bug on the client or on the server.
		 *
		 * If we receive a BAD_SEQID error in the particular case of
		 * doing an OPEN, we assume that nfs_increment_open_seqid() will
		 * have unhashed the old state_owner for us, and that we can
		 * therefore safely retry using a new one. We should still warn
		 * the user though...
		 */
		if (status == -NFS4ERR_BAD_SEQID) {
			pr_warn_ratelimited("NFS: v4 server %s "
					" returned a bad sequence-id error!\n",
					NFS_SERVER(dir)->nfs_client->cl_hostname);
			exception.retry = 1;
			continue;
		}
		/*
		 * BAD_STATEID on OPEN means that the server cancelled our
		 * state before it received the OPEN_CONFIRM.
		 * Recover by retrying the request as per the discussion
		 * on Page 181 of RFC3530.
		 */
		if (status == -NFS4ERR_BAD_STATEID) {
			exception.retry = 1;
			continue;
		}
		if (status == -NFS4ERR_EXPIRED) {
			nfs4_schedule_lease_recovery(server->nfs_client);
			exception.retry = 1;
			continue;
		}
		if (status == -EAGAIN) {
			/* We must have found a delegation */
			exception.retry = 1;
			continue;
		}
		if (nfs4_clear_cap_atomic_open_v1(server, status, &exception))
			continue;
		res = ERR_PTR(nfs4_handle_exception(server,
					status, &exception));
	} while (exception.retry);
	return res;
}


static void nfs4_init_boot_verifier(const struct nfs_client *clp,
				    nfs4_verifier *bootverf)
{
	__be32 verf[2];

	if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
		/* An impossible timestamp guarantees this value
		 * will never match a generated boot time. */
		verf[0] = cpu_to_be32(U32_MAX);
		verf[1] = cpu_to_be32(U32_MAX);
	} else {
		struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
		u64 ns = ktime_to_ns(nn->boot_time);

		verf[0] = cpu_to_be32(ns >> 32);
		verf[1] = cpu_to_be32(ns);
	}
	memcpy(bootverf->data, verf, sizeof(bootverf->data));
}


encode_layoutget(struct xdr_stream *xdr,
		      const struct nfs4_layoutget_args *args,
		      struct compound_hdr *hdr)
{
}


static int decode_attr_mdsthreshold(struct xdr_stream *xdr,
				    uint32_t *bitmap,
				    struct nfs4_threshold *res)
{
	__be32 *p;
	int status = 0;
	uint32_t num;

	if (unlikely(bitmap[2] & (FATTR4_WORD2_MDSTHRESHOLD - 1U)))
		return -EIO;
	if (bitmap[2] & FATTR4_WORD2_MDSTHRESHOLD) {
		/* Did the server return an unrequested attribute? */
		if (unlikely(res == NULL))
			return -EREMOTEIO;
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(!p))
			return -EIO;
		num = be32_to_cpup(p);
		if (num == 0)
			return 0;
		if (num > 1)
			printk(KERN_INFO "%s: Warning: Multiple pNFS layout "
				"drivers per filesystem not supported\n",
				__func__);

		status = decode_first_threshold_item4(xdr, res);
		bitmap[2] &= ~FATTR4_WORD2_MDSTHRESHOLD;
	}
	return status;
}


static void nfs4_bitmap_copy_adjust(__u32 *dst, const __u32 *src,
		struct inode *inode)
{
	unsigned long cache_validity;

	memcpy(dst, src, NFS4_BITMASK_SZ*sizeof(*dst));
	if (!inode || !nfs4_have_delegation(inode, FMODE_READ))
		return;

	cache_validity = READ_ONCE(NFS_I(inode)->cache_validity);
	if (!(cache_validity & NFS_INO_REVAL_FORCED))
		cache_validity &= ~(NFS_INO_INVALID_CHANGE
				| NFS_INO_INVALID_SIZE);

	if (!(cache_validity & NFS_INO_INVALID_SIZE))
		dst[0] &= ~FATTR4_WORD0_SIZE;

	if (!(cache_validity & NFS_INO_INVALID_CHANGE))
		dst[0] &= ~FATTR4_WORD0_CHANGE;
}


static int decode_lookupp(struct xdr_stream *xdr)
{
	return decode_op_hdr(xdr, OP_LOOKUPP);
}


static int nfs4_xattr_set_nfs4_acl(const struct xattr_handler *handler,
				   struct dentry *unused, struct inode *inode,
				   const char *key, const void *buf,
				   size_t buflen, int flags)
{
	return nfs4_proc_set_acl(inode, buf, buflen);
}


nfs4_init_uniform_client_string(struct nfs_client *clp)
{
	size_t len;
	char *str;

	if (clp->cl_owner_id != NULL)
		return 0;

	if (nfs4_client_id_uniquifier[0] != '\0')
		return nfs4_init_uniquifier_client_string(clp);

	len = 10 + 10 + 1 + 10 + 1 +
		strlen(clp->cl_rpcclient->cl_nodename) + 1;

	if (len > NFS4_OPAQUE_LIMIT + 1)
		return -EINVAL;

	/*
	 * Since this string is allocated at mount time, and held until the
	 * nfs_client is destroyed, we can use GFP_KERNEL here w/o worrying
	 * about a memory-reclaim deadlock.
	 */
	str = kmalloc(len, GFP_KERNEL);
	if (!str)
		return -ENOMEM;

	scnprintf(str, len, "Linux NFSv%u.%u %s",
			clp->rpc_ops->version, clp->cl_minorversion,
			clp->cl_rpcclient->cl_nodename);
	clp->cl_owner_id = str;
	return 0;
}


static void nfs4_xdr_enc_destroy_session(struct rpc_rqst *req,
					 struct xdr_stream *xdr,
					 const void *data)
{
	const struct nfs4_session *session = data;
	struct compound_hdr hdr = {
		.minorversion = session->clp->cl_mvops->minor_version,
	};

	encode_compound_hdr(xdr, req, &hdr);
	encode_destroy_session(xdr, session, &hdr);
	encode_nops(&hdr);
}


static int decode_attr_exclcreat_supported(struct xdr_stream *xdr,
				 uint32_t *bitmap, uint32_t *bitmask)
{
	if (likely(bitmap[2] & FATTR4_WORD2_SUPPATTR_EXCLCREAT)) {
		int ret;
		ret = decode_attr_bitmap(xdr, bitmask);
		if (unlikely(ret < 0))
			return ret;
		bitmap[2] &= ~FATTR4_WORD2_SUPPATTR_EXCLCREAT;
	} else
		bitmask[0] = bitmask[1] = bitmask[2] = 0;
	dprintk("%s: bitmask=%08x:%08x:%08x\n", __func__,
		bitmask[0], bitmask[1], bitmask[2]);
	return 0;
}


static int nfs4_proc_mknod(struct inode *dir, struct dentry *dentry,
		struct iattr *sattr, dev_t rdev)
{
	struct nfs_server *server = NFS_SERVER(dir);
	struct nfs4_exception exception = {
		.interruptible = true,
	};
	struct nfs4_label l, *label = NULL;
	int err;

	label = nfs4_label_init_security(dir, dentry, sattr, &l);

	if (!(server->attr_bitmask[2] & FATTR4_WORD2_MODE_UMASK))
		sattr->ia_mode &= ~current_umask();
	do {
		err = _nfs4_proc_mknod(dir, dentry, sattr, label, rdev);
		trace_nfs4_mknod(dir, &dentry->d_name, err);
		err = nfs4_handle_exception(NFS_SERVER(dir), err,
				&exception);
	} while (exception.retry);

	nfs4_label_release_security(label);

	return err;
}


static int nfs4_proc_link(struct inode *inode, struct inode *dir, const struct qstr *name)
{
	struct nfs4_exception exception = {
		.interruptible = true,
	};
	int err;
	do {
		err = nfs4_handle_exception(NFS_SERVER(inode),
				_nfs4_proc_link(inode, dir, name),
				&exception);
	} while (exception.retry);
	return err;
}


nfs4_label_init_security(struct inode *dir, struct dentry *dentry,
	struct iattr *sattr, struct nfs4_label *l)
{ return NULL; }


static int nfs4_xdr_dec_open_confirm(struct rpc_rqst *rqstp,
				     struct xdr_stream *xdr,
				     void *data)
{
	struct nfs_open_confirmres *res = data;
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (status)
		goto out;
	status = decode_putfh(xdr);
	if (status)
		goto out;
	status = decode_open_confirm(xdr, res);
out:
	return status;
}


static bool nfs4_read_stateid_changed(struct rpc_task *task,
		struct nfs_pgio_args *args)
{

	if (!nfs4_error_stateid_expired(task->tk_status) ||
		nfs4_stateid_is_current(&args->stateid,
				args->context,
				args->lock_context,
				FMODE_READ))
		return false;
	rpc_restart_call_prepare(task);
	return true;
}


int nfs4_proc_fs_locations(struct rpc_clnt *client, struct inode *dir,
			   const struct qstr *name,
			   struct nfs4_fs_locations *fs_locations,
			   struct page *page)
{
	struct nfs4_exception exception = {
		.interruptible = true,
	};
	int err;
	do {
		err = _nfs4_proc_fs_locations(client, dir, name,
				fs_locations, page);
		trace_nfs4_get_fs_locations(dir, name, err);
		err = nfs4_handle_exception(NFS_SERVER(dir), err,
				&exception);
	} while (exception.retry);
	return err;
}


static int nfs4_xdr_dec_setclientid(struct rpc_rqst *req,
				    struct xdr_stream *xdr,
				    void *data)
{
	struct nfs4_setclientid_res *res = data;
	struct compound_hdr hdr;
	int status;

	status = decode_compound_hdr(xdr, &hdr);
	if (!status)
		status = decode_setclientid(xdr, res);
	return status;
}


static int decode_create(struct xdr_stream *xdr, struct nfs4_change_info *cinfo)
{
	__be32 *p;
	uint32_t bmlen;
	int status;

	status = decode_op_hdr(xdr, OP_CREATE);
	if (status)
		return status;
	if ((status = decode_change_info(xdr, cinfo)))
		return status;
	p = xdr_inline_decode(xdr, 4);
	if (unlikely(!p))
		return -EIO;
	bmlen = be32_to_cpup(p);
	p = xdr_inline_decode(xdr, bmlen << 2);
	if (likely(p))
		return 0;
	return -EIO;
}


static int nfs4_commit_done_cb(struct rpc_task *task, struct nfs_commit_data *data)
{
	struct inode *inode = data->inode;

	trace_nfs4_commit(data, task->tk_status);
	if (nfs4_async_handle_error(task, NFS_SERVER(inode),
				    NULL, NULL) == -EAGAIN) {
		rpc_restart_call_prepare(task);
		return -EAGAIN;
	}
	return 0;
}


static ssize_t xdr_encode_bitmap4(struct xdr_stream *xdr,
		const __u32 *bitmap, size_t len)
{
	ssize_t ret;

	/* Trim empty words */
	while (len > 0 && bitmap[len-1] == 0)
		len--;
	ret = xdr_stream_encode_uint32_array(xdr, bitmap, len);
	if (WARN_ON_ONCE(ret < 0))
		return ret;
	return len;
}


int nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
		       bool plus)
{
	unsigned int savep;
	uint32_t bitmap[3] = {0};
	uint32_t len;
	uint64_t new_cookie;
	__be32 *p = xdr_inline_decode(xdr, 4);
	if (unlikely(!p))
		return -EAGAIN;
	if (*p == xdr_zero) {
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(!p))
			return -EAGAIN;
		if (*p == xdr_zero)
			return -EAGAIN;
		entry->eof = 1;
		return -EBADCOOKIE;
	}

	p = xdr_inline_decode(xdr, 12);
	if (unlikely(!p))
		return -EAGAIN;
	p = xdr_decode_hyper(p, &new_cookie);
	entry->len = be32_to_cpup(p);

	p = xdr_inline_decode(xdr, entry->len);
	if (unlikely(!p))
		return -EAGAIN;
	entry->name = (const char *) p;

	/*
	 * In case the server doesn't return an inode number,
	 * we fake one here.  (We don't use inode number 0,
	 * since glibc seems to choke on it...)
	 */
	entry->ino = 1;
	entry->fattr->valid = 0;

	if (decode_attr_bitmap(xdr, bitmap) < 0)
		return -EAGAIN;

	if (decode_attr_length(xdr, &len, &savep) < 0)
		return -EAGAIN;

	if (decode_getfattr_attrs(xdr, bitmap, entry->fattr, entry->fh,
			NULL, entry->label, entry->server) < 0)
		return -EAGAIN;
	if (entry->fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
		entry->ino = entry->fattr->mounted_on_fileid;
	else if (entry->fattr->valid & NFS_ATTR_FATTR_FILEID)
		entry->ino = entry->fattr->fileid;

	entry->d_type = DT_UNKNOWN;
	if (entry->fattr->valid & NFS_ATTR_FATTR_TYPE)
		entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);

	entry->prev_cookie = entry->cookie;
	entry->cookie = new_cookie;

	return 0;
}


static void nfs4_layoutcommit_release(void *calldata)
{
	struct nfs4_layoutcommit_data *data = calldata;

	pnfs_cleanup_layoutcommit(data);
	nfs_post_op_update_inode_force_wcc(data->args.inode,
					   data->res.fattr);
	put_cred(data->cred);
	nfs_iput_and_deactive(data->inode);
	kfree(data);
}


static void nfs41_sequence_call_done(struct rpc_task *task, void *data)
{
	struct nfs4_sequence_data *calldata = data;
	struct nfs_client *clp = calldata->clp;

	if (!nfs41_sequence_done(task, task->tk_msg.rpc_resp))
		return;

	trace_nfs4_sequence(clp, task->tk_status);
	if (task->tk_status < 0) {
		dprintk("%s ERROR %d\n", __func__, task->tk_status);
		if (refcount_read(&clp->cl_count) == 1)
			goto out;

		if (nfs41_sequence_handle_errors(task, clp) == -EAGAIN) {
			rpc_restart_call_prepare(task);
			return;
		}
	}
	dprintk("%s rpc_cred %p\n", __func__, task->tk_msg.rpc_cred);
out:
	dprintk("<-- %s\n", __func__);
}


nfs41_find_root_sec(struct nfs_server *server, struct nfs_fh *fhandle,
		    struct nfs_fsinfo *info)
{
	int err;
	struct page *page;
	rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
	struct nfs4_secinfo_flavors *flavors;
	struct nfs4_secinfo4 *secinfo;
	int i;

	page = alloc_page(GFP_KERNEL);
	if (!page) {
		err = -ENOMEM;
		goto out;
	}

	flavors = page_address(page);
	err = nfs41_proc_secinfo_no_name(server, fhandle, info, flavors);

	/*
	 * Fall back on "guess and check" method if
	 * the server doesn't support SECINFO_NO_NAME
	 */
	if (err == -NFS4ERR_WRONGSEC || err == -ENOTSUPP) {
		err = nfs4_find_root_sec(server, fhandle, info);
		goto out_freepage;
	}
	if (err)
		goto out_freepage;

	for (i = 0; i < flavors->num_flavors; i++) {
		secinfo = &flavors->flavors[i];

		switch (secinfo->flavor) {
		case RPC_AUTH_NULL:
		case RPC_AUTH_UNIX:
		case RPC_AUTH_GSS:
			flavor = rpcauth_get_pseudoflavor(secinfo->flavor,
					&secinfo->flavor_info);
			break;
		default:
			flavor = RPC_AUTH_MAXFLAVOR;
			break;
		}

		if (!nfs_auth_info_match(&server->auth_info, flavor))
			flavor = RPC_AUTH_MAXFLAVOR;

		if (flavor != RPC_AUTH_MAXFLAVOR) {
			err = nfs4_lookup_root_sec(server, fhandle,
						   info, flavor);
			if (!err)
				break;
		}
	}

	if (flavor == RPC_AUTH_MAXFLAVOR)
		err = -EPERM;

out_freepage:
	put_page(page);
	if (err == -EACCES)
		return -EPERM;
out:
	return err;
}


static void nfs4_release_lockowner_done(struct rpc_task *task, void *calldata)
{
	struct nfs_release_lockowner_data *data = calldata;
	struct nfs_server *server = data->server;

	nfs40_sequence_done(task, &data->res.seq_res);

	switch (task->tk_status) {
	case 0:
		renew_lease(server, data->timestamp);
		break;
	case -NFS4ERR_STALE_CLIENTID:
	case -NFS4ERR_EXPIRED:
		nfs4_schedule_lease_recovery(server->nfs_client);
		break;
	case -NFS4ERR_LEASE_MOVED:
	case -NFS4ERR_DELAY:
		if (nfs4_async_handle_error(task, server,
					    NULL, NULL) == -EAGAIN)
			rpc_restart_call_prepare(task);
	}
}


static int nfs4_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle, struct nfs_fsstat *fsstat)
{
	struct nfs4_exception exception = {
		.interruptible = true,
	};
	int err;
	do {
		err = nfs4_handle_exception(server,
				_nfs4_proc_statfs(server, fhandle, fsstat),
				&exception);
	} while (exception.retry);
	return err;
}


static void nfs4_setclientid_done(struct rpc_task *task, void *calldata)
{
	struct nfs4_setclientid *sc = calldata;

	if (task->tk_status == 0)
		sc->sc_cred = get_rpccred(task->tk_rqstp->rq_cred);
}