nfs4proc.c

static int do_vfs_lock(struct file *file, struct file_lock *fl)
{
	int res = 0;
	switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
		case FL_POSIX:
			res = posix_lock_file_wait(file, fl);
			break;
		case FL_FLOCK:
			res = flock_lock_file_wait(file, fl);
			break;
		default:
			BUG();
	}
	return res;
}

struct nfs4_unlockdata {
	struct nfs_locku_args arg;
	struct nfs_locku_res res;
	struct nfs4_lock_state *lsp;
	struct nfs_open_context *ctx;
	struct file_lock fl;
	const struct nfs_server *server;
	unsigned long timestamp;
};

static struct nfs4_unlockdata *nfs4_alloc_unlockdata(struct file_lock *fl,
		struct nfs_open_context *ctx,
		struct nfs4_lock_state *lsp,
		struct nfs_seqid *seqid)
{
	struct nfs4_unlockdata *p;
	struct inode *inode = lsp->ls_state->inode;

	p = kzalloc(sizeof(*p), GFP_NOFS);
	if (p == NULL)
		return NULL;
	p->arg.fh = NFS_FH(inode);
	p->arg.fl = &p->fl;
	p->arg.seqid = seqid;
	p->res.seqid = seqid;
	p->arg.stateid = &lsp->ls_stateid;
	p->lsp = lsp;
	atomic_inc(&lsp->ls_count);
	/* Ensure we don't close file until we're done freeing locks! */
	p->ctx = get_nfs_open_context(ctx);
	memcpy(&p->fl, fl, sizeof(p->fl));
	p->server = NFS_SERVER(inode);
	return p;
}

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);
	put_nfs_open_context(calldata->ctx);
	kfree(calldata);
}

static void nfs4_locku_done(struct rpc_task *task, void *data)
{
	struct nfs4_unlockdata *calldata = data;

	if (!nfs4_sequence_done(task, &calldata->res.seq_res))
		return;
	switch (task->tk_status) {
		case 0:
			memcpy(calldata->lsp->ls_stateid.data,
					calldata->res.stateid.data,
					sizeof(calldata->lsp->ls_stateid.data));
			renew_lease(calldata->server, calldata->timestamp);
			break;
		case -NFS4ERR_BAD_STATEID:
		case -NFS4ERR_OLD_STATEID:
		case -NFS4ERR_STALE_STATEID:
		case -NFS4ERR_EXPIRED:
			break;
		default:
			if (nfs4_async_handle_error(task, calldata->server, NULL) == -EAGAIN)
				nfs_restart_rpc(task,
						 calldata->server->nfs_client);
	}
}

static void nfs4_locku_prepare(struct rpc_task *task, void *data)
{
	struct nfs4_unlockdata *calldata = data;

	if (nfs_wait_on_sequence(calldata->arg.seqid, task) != 0)
		return;
	if ((calldata->lsp->ls_flags & NFS_LOCK_INITIALIZED) == 0) {
		/* Note: exit _without_ running nfs4_locku_done */
		task->tk_action = NULL;
		return;
	}
	calldata->timestamp = jiffies;
	if (nfs4_setup_sequence(calldata->server,
				&calldata->arg.seq_args,
				&calldata->res.seq_res, 1, task))
		return;
	rpc_call_start(task);
}

static const struct rpc_call_ops nfs4_locku_ops = {
	.rpc_call_prepare = nfs4_locku_prepare,
	.rpc_call_done = nfs4_locku_done,
	.rpc_release = nfs4_locku_release_calldata,
};

static struct rpc_task *nfs4_do_unlck(struct file_lock *fl,
		struct nfs_open_context *ctx,
		struct nfs4_lock_state *lsp,
		struct nfs_seqid *seqid)
{
	struct nfs4_unlockdata *data;
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOCKU],
		.rpc_cred = ctx->cred,
	};
	struct rpc_task_setup task_setup_data = {
		.rpc_client = NFS_CLIENT(lsp->ls_state->inode),
		.rpc_message = &msg,
		.callback_ops = &nfs4_locku_ops,
		.workqueue = nfsiod_workqueue,
		.flags = RPC_TASK_ASYNC,
	};

	/* Ensure this is an unlock - when canceling a lock, the
	 * canceled lock is passed in, and it won't be an unlock.
	 */
	fl->fl_type = F_UNLCK;

	data = nfs4_alloc_unlockdata(fl, ctx, lsp, seqid);
	if (data == NULL) {
		nfs_free_seqid(seqid);
		return ERR_PTR(-ENOMEM);
	}

	msg.rpc_argp = &data->arg;
	msg.rpc_resp = &data->res;
	task_setup_data.callback_data = data;
	return rpc_run_task(&task_setup_data);
}

static int nfs4_proc_unlck(struct nfs4_state *state, int cmd, struct file_lock *request)
{
	struct nfs_inode *nfsi = NFS_I(state->inode);
	struct nfs_seqid *seqid;
	struct nfs4_lock_state *lsp;
	struct rpc_task *task;
	int status = 0;
	unsigned char fl_flags = request->fl_flags;

	status = nfs4_set_lock_state(state, request);
	/* Unlock _before_ we do the RPC call */
	request->fl_flags |= FL_EXISTS;
	down_read(&nfsi->rwsem);
	if (do_vfs_lock(request->fl_file, request) == -ENOENT) {
		up_read(&nfsi->rwsem);
		goto out;
	}
	up_read(&nfsi->rwsem);
	if (status != 0)
		goto out;
	/* Is this a delegated lock? */
	if (test_bit(NFS_DELEGATED_STATE, &state->flags))
		goto out;
	lsp = request->fl_u.nfs4_fl.owner;
	seqid = nfs_alloc_seqid(&lsp->ls_seqid, GFP_KERNEL);
	status = -ENOMEM;
	if (seqid == NULL)
		goto out;
	task = nfs4_do_unlck(request, nfs_file_open_context(request->fl_file), lsp, seqid);
	status = PTR_ERR(task);
	if (IS_ERR(task))
		goto out;
	status = nfs4_wait_for_completion_rpc_task(task);
	rpc_put_task(task);
out:
	request->fl_flags = fl_flags;
	return status;
}

struct nfs4_lockdata {
	struct nfs_lock_args arg;
	struct nfs_lock_res res;
	struct nfs4_lock_state *lsp;
	struct nfs_open_context *ctx;
	struct file_lock fl;
	unsigned long timestamp;
	int rpc_status;
	int cancelled;
	struct nfs_server *server;
};

static struct nfs4_lockdata *nfs4_alloc_lockdata(struct file_lock *fl,
		struct nfs_open_context *ctx, struct nfs4_lock_state *lsp,
		gfp_t gfp_mask)
{
	struct nfs4_lockdata *p;
	struct inode *inode = lsp->ls_state->inode;
	struct nfs_server *server = NFS_SERVER(inode);

	p = kzalloc(sizeof(*p), gfp_mask);
	if (p == NULL)
		return NULL;

	p->arg.fh = NFS_FH(inode);
	p->arg.fl = &p->fl;
	p->arg.open_seqid = nfs_alloc_seqid(&lsp->ls_state->owner->so_seqid, gfp_mask);
	if (p->arg.open_seqid == NULL)
		goto out_free;
	p->arg.lock_seqid = nfs_alloc_seqid(&lsp->ls_seqid, gfp_mask);
	if (p->arg.lock_seqid == NULL)
		goto out_free_seqid;
	p->arg.lock_stateid = &lsp->ls_stateid;
	p->arg.lock_owner.clientid = server->nfs_client->cl_clientid;
	p->arg.lock_owner.id = lsp->ls_id.id;
	p->arg.lock_owner.s_dev = server->s_dev;
	p->res.lock_seqid = p->arg.lock_seqid;
	p->lsp = lsp;
	p->server = server;
	atomic_inc(&lsp->ls_count);
	p->ctx = get_nfs_open_context(ctx);
	memcpy(&p->fl, fl, sizeof(p->fl));
	return p;
out_free_seqid:
	nfs_free_seqid(p->arg.open_seqid);
out_free:
	kfree(p);
	return NULL;
}

static void nfs4_lock_prepare(struct rpc_task *task, void *calldata)
{
	struct nfs4_lockdata *data = calldata;
	struct nfs4_state *state = data->lsp->ls_state;

	dprintk("%s: begin!\n", __func__);
	if (nfs_wait_on_sequence(data->arg.lock_seqid, task) != 0)
		return;
	/* Do we need to do an open_to_lock_owner? */
	if (!(data->arg.lock_seqid->sequence->flags & NFS_SEQID_CONFIRMED)) {
		if (nfs_wait_on_sequence(data->arg.open_seqid, task) != 0)
			return;
		data->arg.open_stateid = &state->stateid;
		data->arg.new_lock_owner = 1;
		data->res.open_seqid = data->arg.open_seqid;
	} else
		data->arg.new_lock_owner = 0;
	data->timestamp = jiffies;
	if (nfs4_setup_sequence(data->server,
				&data->arg.seq_args,
				&data->res.seq_res, 1, task))
		return;
	rpc_call_start(task);
	dprintk("%s: done!, ret = %d\n", __func__, data->rpc_status);
}

static void nfs4_recover_lock_prepare(struct rpc_task *task, void *calldata)
{
	rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
	nfs4_lock_prepare(task, calldata);
}

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

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

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

	data->rpc_status = task->tk_status;
	if (data->arg.new_lock_owner != 0) {
		if (data->rpc_status == 0)
			nfs_confirm_seqid(&data->lsp->ls_seqid, 0);
		else
			goto out;
	}
	if (data->rpc_status == 0) {
		memcpy(data->lsp->ls_stateid.data, data->res.stateid.data,
					sizeof(data->lsp->ls_stateid.data));
		data->lsp->ls_flags |= NFS_LOCK_INITIALIZED;
		renew_lease(NFS_SERVER(data->ctx->path.dentry->d_inode), data->timestamp);
	}
out:
	dprintk("%s: done, ret = %d!\n", __func__, data->rpc_status);
}

static void nfs4_lock_release(void *calldata)
{
	struct nfs4_lockdata *data = calldata;

	dprintk("%s: begin!\n", __func__);
	nfs_free_seqid(data->arg.open_seqid);
	if (data->cancelled != 0) {
		struct rpc_task *task;
		task = nfs4_do_unlck(&data->fl, data->ctx, data->lsp,
				data->arg.lock_seqid);
		if (!IS_ERR(task))
			rpc_put_task_async(task);
		dprintk("%s: cancelling lock!\n", __func__);
	} else
		nfs_free_seqid(data->arg.lock_seqid);
	nfs4_put_lock_state(data->lsp);
	put_nfs_open_context(data->ctx);
	kfree(data);
	dprintk("%s: done!\n", __func__);
}

static const struct rpc_call_ops nfs4_lock_ops = {
	.rpc_call_prepare = nfs4_lock_prepare,
	.rpc_call_done = nfs4_lock_done,
	.rpc_release = nfs4_lock_release,
};

static const struct rpc_call_ops nfs4_recover_lock_ops = {
	.rpc_call_prepare = nfs4_recover_lock_prepare,
	.rpc_call_done = nfs4_lock_done,
	.rpc_release = nfs4_lock_release,
};

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_BAD_STATEID:
		lsp->ls_seqid.flags &= ~NFS_SEQID_CONFIRMED;
		if (new_lock_owner != 0 ||
		   (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0)
			nfs4_schedule_stateid_recovery(server, lsp->ls_state);
		break;
	case -NFS4ERR_STALE_STATEID:
		lsp->ls_seqid.flags &= ~NFS_SEQID_CONFIRMED;
	case -NFS4ERR_EXPIRED:
		nfs4_schedule_lease_recovery(server->nfs_client);
	};
}

static int _nfs4_do_setlk(struct nfs4_state *state, int cmd, struct file_lock *fl, int recovery_type)
{
	struct nfs4_lockdata *data;
	struct rpc_task *task;
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOCK],
		.rpc_cred = state->owner->so_cred,
	};
	struct rpc_task_setup task_setup_data = {
		.rpc_client = NFS_CLIENT(state->inode),
		.rpc_message = &msg,
		.callback_ops = &nfs4_lock_ops,
		.workqueue = nfsiod_workqueue,
		.flags = RPC_TASK_ASYNC,
	};
	int ret;

	dprintk("%s: begin!\n", __func__);
	data = nfs4_alloc_lockdata(fl, nfs_file_open_context(fl->fl_file),
			fl->fl_u.nfs4_fl.owner,
			recovery_type == NFS_LOCK_NEW ? GFP_KERNEL : GFP_NOFS);
	if (data == NULL)
		return -ENOMEM;
	if (IS_SETLKW(cmd))
		data->arg.block = 1;
	if (recovery_type > NFS_LOCK_NEW) {
		if (recovery_type == NFS_LOCK_RECLAIM)
			data->arg.reclaim = NFS_LOCK_RECLAIM;
		task_setup_data.callback_ops = &nfs4_recover_lock_ops;
	}
	msg.rpc_argp = &data->arg;
	msg.rpc_resp = &data->res;
	task_setup_data.callback_data = data;
	task = rpc_run_task(&task_setup_data);
	if (IS_ERR(task))
		return PTR_ERR(task);
	ret = nfs4_wait_for_completion_rpc_task(task);
	if (ret == 0) {
		ret = data->rpc_status;
		if (ret)
			nfs4_handle_setlk_error(data->server, data->lsp,
					data->arg.new_lock_owner, ret);
	} else
		data->cancelled = 1;
	rpc_put_task(task);
	dprintk("%s: done, ret = %d!\n", __func__, ret);
	return ret;
}

static int nfs4_lock_reclaim(struct nfs4_state *state, struct file_lock *request)
{
	struct nfs_server *server = NFS_SERVER(state->inode);
	struct nfs4_exception exception = { };
	int err;

	do {
		/* Cache the lock if possible... */
		if (test_bit(NFS_DELEGATED_STATE, &state->flags) != 0)
			return 0;
		err = _nfs4_do_setlk(state, F_SETLK, request, NFS_LOCK_RECLAIM);
		if (err != -NFS4ERR_DELAY)
			break;
		nfs4_handle_exception(server, err, &exception);
	} while (exception.retry);
	return err;
}

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 = { };
	int err;

	err = nfs4_set_lock_state(state, request);
	if (err != 0)
		return err;
	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_proc_setlk(struct nfs4_state *state, int cmd, struct file_lock *request)
{
	struct nfs_inode *nfsi = NFS_I(state->inode);
	unsigned char fl_flags = request->fl_flags;
	int status = -ENOLCK;

	if ((fl_flags & FL_POSIX) &&
			!test_bit(NFS_STATE_POSIX_LOCKS, &state->flags))
		goto out;
	/* Is this a delegated open? */
	status = nfs4_set_lock_state(state, request);
	if (status != 0)
		goto out;
	request->fl_flags |= FL_ACCESS;
	status = do_vfs_lock(request->fl_file, request);
	if (status < 0)
		goto out;
	down_read(&nfsi->rwsem);
	if (test_bit(NFS_DELEGATED_STATE, &state->flags)) {
		/* Yes: cache locks! */
		/* ...but avoid races with delegation recall... */
		request->fl_flags = fl_flags & ~FL_SLEEP;
		status = do_vfs_lock(request->fl_file, request);
		goto out_unlock;
	}
	status = _nfs4_do_setlk(state, cmd, request, NFS_LOCK_NEW);
	if (status != 0)
		goto out_unlock;
	/* Note: we always want to sleep here! */
	request->fl_flags = fl_flags | FL_SLEEP;
	if (do_vfs_lock(request->fl_file, request) < 0)
		printk(KERN_WARNING "%s: VFS is out of sync with lock manager!\n", __func__);
out_unlock:
	up_read(&nfsi->rwsem);
out:
	request->fl_flags = fl_flags;
	return status;
}

static int nfs4_proc_setlk(struct nfs4_state *state, int cmd, struct file_lock *request)
{
	struct nfs4_exception exception = { };
	int err;

	do {
		err = _nfs4_proc_setlk(state, cmd, request);
		if (err == -NFS4ERR_DENIED)
			err = -EAGAIN;
		err = nfs4_handle_exception(NFS_SERVER(state->inode),
				err, &exception);
	} while (exception.retry);
	return err;
}

static int
nfs4_proc_lock(struct file *filp, int cmd, struct file_lock *request)
{
	struct nfs_open_context *ctx;
	struct nfs4_state *state;
	unsigned long timeout = NFS4_LOCK_MINTIMEOUT;
	int status;

	/* verify open state */
	ctx = nfs_file_open_context(filp);
	state = ctx->state;

	if (request->fl_start < 0 || request->fl_end < 0)
		return -EINVAL;

	if (IS_GETLK(cmd)) {
		if (state != NULL)
			return nfs4_proc_getlk(state, F_GETLK, request);
		return 0;
	}

	if (!(IS_SETLK(cmd) || IS_SETLKW(cmd)))
		return -EINVAL;

	if (request->fl_type == F_UNLCK) {
		if (state != NULL)
			return nfs4_proc_unlck(state, cmd, request);
		return 0;
	}

	if (state == NULL)
		return -ENOLCK;
	do {
		status = nfs4_proc_setlk(state, cmd, request);
		if ((status != -EAGAIN) || IS_SETLK(cmd))
			break;
		timeout = nfs4_set_lock_task_retry(timeout);
		status = -ERESTARTSYS;
		if (signalled())
			break;
	} while(status < 0);
	return status;
}

int nfs4_lock_delegation_recall(struct nfs4_state *state, struct file_lock *fl)
{
	struct nfs_server *server = NFS_SERVER(state->inode);
	struct nfs4_exception exception = { };
	int err;

	err = nfs4_set_lock_state(state, fl);
	if (err != 0)
		goto out;
	do {
		err = _nfs4_do_setlk(state, F_SETLK, fl, NFS_LOCK_NEW);
		switch (err) {
			default:
				printk(KERN_ERR "%s: unhandled error %d.\n",
						__func__, err);
			case 0:
			case -ESTALE:
				goto out;
			case -NFS4ERR_EXPIRED:
			case -NFS4ERR_STALE_CLIENTID:
			case -NFS4ERR_STALE_STATEID:
				nfs4_schedule_lease_recovery(server->nfs_client);
				goto out;
			case -NFS4ERR_BADSESSION:
			case -NFS4ERR_BADSLOT:
			case -NFS4ERR_BAD_HIGH_SLOT:
			case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
			case -NFS4ERR_DEADSESSION:
				nfs4_schedule_session_recovery(server->nfs_client->cl_session);
				goto out;
			case -ERESTARTSYS:
				/*
				 * The show must go on: exit, but mark the
				 * stateid as needing recovery.
				 */
			case -NFS4ERR_ADMIN_REVOKED:
			case -NFS4ERR_BAD_STATEID:
			case -NFS4ERR_OPENMODE:
				nfs4_schedule_stateid_recovery(server, state);
				err = 0;
				goto out;
			case -EKEYEXPIRED:
				/*
				 * User RPCSEC_GSS context has expired.
				 * We cannot recover this stateid now, so
				 * skip it and allow recovery thread to
				 * proceed.
				 */
				err = 0;
				goto out;
			case -ENOMEM:
			case -NFS4ERR_DENIED:
				/* kill_proc(fl->fl_pid, SIGLOST, 1); */
				err = 0;
				goto out;
			case -NFS4ERR_DELAY:
				break;
		}
		err = nfs4_handle_exception(server, err, &exception);
	} while (exception.retry);
out:
	return err;
}

static void nfs4_release_lockowner_release(void *calldata)
{
	kfree(calldata);
}

const struct rpc_call_ops nfs4_release_lockowner_ops = {
	.rpc_release = nfs4_release_lockowner_release,
};

void nfs4_release_lockowner(const struct nfs4_lock_state *lsp)
{
	struct nfs_server *server = lsp->ls_state->owner->so_server;
	struct nfs_release_lockowner_args *args;
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_RELEASE_LOCKOWNER],
	};

	if (server->nfs_client->cl_mvops->minor_version != 0)
		return;
	args = kmalloc(sizeof(*args), GFP_NOFS);
	if (!args)
		return;
	args->lock_owner.clientid = server->nfs_client->cl_clientid;
	args->lock_owner.id = lsp->ls_id.id;
	args->lock_owner.s_dev = server->s_dev;
	msg.rpc_argp = args;
	rpc_call_async(server->client, &msg, 0, &nfs4_release_lockowner_ops, args);
}

#define XATTR_NAME_NFSV4_ACL "system.nfs4_acl"

static int nfs4_xattr_set_nfs4_acl(struct dentry *dentry, const char *key,
				   const void *buf, size_t buflen,
				   int flags, int type)
{
	if (strcmp(key, "") != 0)
		return -EINVAL;

	return nfs4_proc_set_acl(dentry->d_inode, buf, buflen);
}

static int nfs4_xattr_get_nfs4_acl(struct dentry *dentry, const char *key,
				   void *buf, size_t buflen, int type)
{
	if (strcmp(key, "") != 0)
		return -EINVAL;

	return nfs4_proc_get_acl(dentry->d_inode, buf, buflen);
}

static size_t nfs4_xattr_list_nfs4_acl(struct dentry *dentry, char *list,
				       size_t list_len, const char *name,
				       size_t name_len, int type)
{
	size_t len = sizeof(XATTR_NAME_NFSV4_ACL);

	if (!nfs4_server_supports_acls(NFS_SERVER(dentry->d_inode)))
		return 0;

	if (list && len <= list_len)
		memcpy(list, XATTR_NAME_NFSV4_ACL, len);
	return len;
}

static void nfs_fixup_referral_attributes(struct nfs_fattr *fattr)
{
	if (!((fattr->valid & NFS_ATTR_FATTR_FILEID) &&
		(fattr->valid & NFS_ATTR_FATTR_FSID) &&
		(fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)))
		return;

	fattr->valid |= NFS_ATTR_FATTR_TYPE | NFS_ATTR_FATTR_MODE |
		NFS_ATTR_FATTR_NLINK;
	fattr->mode = S_IFDIR | S_IRUGO | S_IXUGO;
	fattr->nlink = 2;
}

int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
		struct nfs4_fs_locations *fs_locations, struct page *page)
{
	struct nfs_server *server = NFS_SERVER(dir);
	u32 bitmask[2] = {
		[0] = FATTR4_WORD0_FSID | FATTR4_WORD0_FS_LOCATIONS,
		[1] = FATTR4_WORD1_MOUNTED_ON_FILEID,
	};
	struct nfs4_fs_locations_arg args = {
		.dir_fh = NFS_FH(dir),
		.name = name,
		.page = page,
		.bitmask = bitmask,
	};
	struct nfs4_fs_locations_res res = {
		.fs_locations = fs_locations,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_FS_LOCATIONS],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};
	int status;

	dprintk("%s: start\n", __func__);
	nfs_fattr_init(&fs_locations->fattr);
	fs_locations->server = server;
	fs_locations->nlocations = 0;
	status = nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 0);
	nfs_fixup_referral_attributes(&fs_locations->fattr);
	dprintk("%s: returned status = %d\n", __func__, status);
	return status;
}

static int _nfs4_proc_secinfo(struct inode *dir, const struct qstr *name, struct nfs4_secinfo_flavors *flavors)
{
	int status;
	struct nfs4_secinfo_arg args = {
		.dir_fh = NFS_FH(dir),
		.name   = name,
	};
	struct nfs4_secinfo_res res = {
		.flavors     = flavors,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SECINFO],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};

	dprintk("NFS call  secinfo %s\n", name->name);
	status = nfs4_call_sync(NFS_SERVER(dir)->client, NFS_SERVER(dir), &msg, &args.seq_args, &res.seq_res, 0);
	dprintk("NFS reply  secinfo: %d\n", status);
	return status;
}

int nfs4_proc_secinfo(struct inode *dir, const struct qstr *name, struct nfs4_secinfo_flavors *flavors)
{
	struct nfs4_exception exception = { };
	int err;
	do {
		err = nfs4_handle_exception(NFS_SERVER(dir),
				_nfs4_proc_secinfo(dir, name, flavors),
				&exception);
	} while (exception.retry);
	return err;
}

#ifdef CONFIG_NFS_V4_1
/*
 * Check the exchange flags returned by the server for invalid flags, having
 * both PNFS and NON_PNFS flags set, and not having one of NON_PNFS, PNFS, or
 * DS flags set.
 */
static int nfs4_check_cl_exchange_flags(u32 flags)
{
	if (flags & ~EXCHGID4_FLAG_MASK_R)
		goto out_inval;
	if ((flags & EXCHGID4_FLAG_USE_PNFS_MDS) &&
	    (flags & EXCHGID4_FLAG_USE_NON_PNFS))
		goto out_inval;
	if (!(flags & (EXCHGID4_FLAG_MASK_PNFS)))
		goto out_inval;
	return NFS_OK;
out_inval:
	return -NFS4ERR_INVAL;
}

/*
 * nfs4_proc_exchange_id()
 *
 * Since the clientid has expired, all compounds using sessions
 * associated with the stale clientid will be returning
 * NFS4ERR_BADSESSION in the sequence operation, and will therefore
 * be in some phase of session reset.
 */
int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
{
	nfs4_verifier verifier;
	struct nfs41_exchange_id_args args = {
		.client = clp,
		.flags = EXCHGID4_FLAG_SUPP_MOVED_REFER,
	};
	struct nfs41_exchange_id_res res = {
		.client = clp,
	};
	int status;
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_EXCHANGE_ID],
		.rpc_argp = &args,
		.rpc_resp = &res,
		.rpc_cred = cred,
	};
	__be32 *p;

	dprintk("--> %s\n", __func__);
	BUG_ON(clp == NULL);

	p = (u32 *)verifier.data;
	*p++ = htonl((u32)clp->cl_boot_time.tv_sec);
	*p = htonl((u32)clp->cl_boot_time.tv_nsec);
	args.verifier = &verifier;

	args.id_len = scnprintf(args.id, sizeof(args.id),
				"%s/%s.%s/%u",
				clp->cl_ipaddr,
				init_utsname()->nodename,
				init_utsname()->domainname,
				clp->cl_rpcclient->cl_auth->au_flavor);

	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
	if (!status)
		status = nfs4_check_cl_exchange_flags(clp->cl_exchange_flags);
	dprintk("<-- %s status= %d\n", __func__, status);
	return status;
}

struct nfs4_get_lease_time_data {
	struct nfs4_get_lease_time_args *args;
	struct nfs4_get_lease_time_res *res;
	struct nfs_client *clp;
};

static void nfs4_get_lease_time_prepare(struct rpc_task *task,
					void *calldata)
{
	int ret;
	struct nfs4_get_lease_time_data *data =
			(struct nfs4_get_lease_time_data *)calldata;

	dprintk("--> %s\n", __func__);
	rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
	/* just setup sequence, do not trigger session recovery
	   since we're invoked within one */
	ret = nfs41_setup_sequence(data->clp->cl_session,
				   &data->args->la_seq_args,
				   &data->res->lr_seq_res, 0, task);

	BUG_ON(ret == -EAGAIN);
	rpc_call_start(task);
	dprintk("<-- %s\n", __func__);
}

/*
 * Called from nfs4_state_manager thread for session setup, so don't recover
 * from sequence operation or clientid errors.
 */
static void nfs4_get_lease_time_done(struct rpc_task *task, void *calldata)
{
	struct nfs4_get_lease_time_data *data =
			(struct nfs4_get_lease_time_data *)calldata;

	dprintk("--> %s\n", __func__);
	if (!nfs41_sequence_done(task, &data->res->lr_seq_res))
		return;
	switch (task->tk_status) {
	case -NFS4ERR_DELAY:
	case -NFS4ERR_GRACE:
		dprintk("%s Retry: tk_status %d\n", __func__, task->tk_status);
		rpc_delay(task, NFS4_POLL_RETRY_MIN);
		task->tk_status = 0;
		/* fall through */
	case -NFS4ERR_RETRY_UNCACHED_REP:
		nfs_restart_rpc(task, data->clp);
		return;
	}
	dprintk("<-- %s\n", __func__);
}

struct rpc_call_ops nfs4_get_lease_time_ops = {
	.rpc_call_prepare = nfs4_get_lease_time_prepare,
	.rpc_call_done = nfs4_get_lease_time_done,
};

int nfs4_proc_get_lease_time(struct nfs_client *clp, struct nfs_fsinfo *fsinfo)
{
	struct rpc_task *task;
	struct nfs4_get_lease_time_args args;
	struct nfs4_get_lease_time_res res = {
		.lr_fsinfo = fsinfo,
	};
	struct nfs4_get_lease_time_data data = {
		.args = &args,
		.res = &res,
		.clp = clp,
	};
	struct rpc_message msg = {
		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_GET_LEASE_TIME],
		.rpc_argp = &args,
		.rpc_resp = &res,
	};
	struct rpc_task_setup task_setup = {
		.rpc_client = clp->cl_rpcclient,
		.rpc_message = &msg,
		.callback_ops = &nfs4_get_lease_time_ops,
		.callback_data = &data,
		.flags = RPC_TASK_TIMEOUT,
	};
	int status;

	dprintk("--> %s\n", __func__);
	task = rpc_run_task(&task_setup);

	if (IS_ERR(task))
		status = PTR_ERR(task);
	else {
		status = task->tk_status;
		rpc_put_task(task);
	}
	dprintk("<-- %s return %d\n", __func__, status);

	return status;
}

/*
 * Reset a slot table
 */
static int nfs4_reset_slot_table(struct nfs4_slot_table *tbl, u32 max_reqs,
				 int ivalue)
{
	struct nfs4_slot *new = NULL;
	int i;
	int ret = 0;

	dprintk("--> %s: max_reqs=%u, tbl->max_slots %d\n", __func__,
		max_reqs, tbl->max_slots);

	/* Does the newly negotiated max_reqs match the existing slot table? */
	if (max_reqs != tbl->max_slots) {
		ret = -ENOMEM;
		new = kmalloc(max_reqs * sizeof(struct nfs4_slot),
			      GFP_NOFS);
		if (!new)
			goto out;
		ret = 0;
		kfree(tbl->slots);
	}
	spin_lock(&tbl->slot_tbl_lock);
	if (new) {
		tbl->slots = new;
		tbl->max_slots = max_reqs;
	}
	for (i = 0; i < tbl->max_slots; ++i)
		tbl->slots[i].seq_nr = ivalue;
	spin_unlock(&tbl->slot_tbl_lock);
	dprintk("%s: tbl=%p slots=%p max_slots=%d\n", __func__,
		tbl, tbl->slots, tbl->max_slots);
out:
	dprintk("<-- %s: return %d\n", __func__, ret);
	return ret;
}

/*
 * Reset the forechannel and backchannel slot tables
 */
static int nfs4_reset_slot_tables(struct nfs4_session *session)
{
	int status;

	status = nfs4_reset_slot_table(&session->fc_slot_table,
			session->fc_attrs.max_reqs, 1);
	if (status)
		return status;

	status = nfs4_reset_slot_table(&session->bc_slot_table,
			session->bc_attrs.max_reqs, 0);
	return status;
}

/* Destroy the slot table */
static void nfs4_destroy_slot_tables(struct nfs4_session *session)
{
	if (session->fc_slot_table.slots != NULL) {
		kfree(session->fc_slot_table.slots);
		session->fc_slot_table.slots = NULL;
	}
	if (session->bc_slot_table.slots != NULL) {
		kfree(session->bc_slot_table.slots);
		session->bc_slot_table.slots = NULL;
	}
	return;
}

/*
 * Initialize slot table
 */
static int nfs4_init_slot_table(struct nfs4_slot_table *tbl,
		int max_slots, int ivalue)
{
	struct nfs4_slot *slot;
	int ret = -ENOMEM;

	BUG_ON(max_slots > NFS4_MAX_SLOT_TABLE);

	dprintk("--> %s: max_reqs=%u\n", __func__, max_slots);

	slot = kcalloc(max_slots, sizeof(struct nfs4_slot), GFP_NOFS);
	if (!slot)
		goto out;
	ret = 0;

	spin_lock(&tbl->slot_tbl_lock);
	tbl->max_slots = max_slots;
	tbl->slots = slot;
	tbl->highest_used_slotid = -1;  /* no slot is currently used */
	spin_unlock(&tbl->slot_tbl_lock);