Message-ID: <51597453.4010106@parallels.com>
Date: Mon, 1 Apr 2013 15:49:39 +0400
From: Stanislav Kinsbursky <skinsbursky@parallels.com>
MIME-Version: 1.0
To: Jeff Layton <jlayton@redhat.com>
CC: <bfields@fieldses.org>, <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH] nfsd: remove support for nfsdcld
References: <1363957031-10579-1-git-send-email-jlayton@redhat.com> <51593D11.5070702@parallels.com> <20130401074149.51a4b4f2@tlielax.poochiereds.net>
In-Reply-To: <20130401074149.51a4b4f2@tlielax.poochiereds.net>
Content-Type: text/plain; charset="windows-1251"; format=flowed
Sender: linux-nfs-owner@vger.kernel.org

01.04.2013 15:41, Jeff Layton ?????:
> On Mon, 1 Apr 2013 11:53:53 +0400
> Stanislav Kinsbursky <skinsbursky@parallels.com> wrote:
>
>> 22.03.2013 16:57, Jeff Layton ?????:
>>> ...as advertised for 3.10.
>>>
>>
>> It looks like UMH should be containerised as fast as possible, doesn't it?
>> Bruce, don't you know, how much time left before 3.10 merge window?
>>
>
> Yes, that would be ideal. I'd estimate that we have about a month or so?
>
> Just from a quick look it doesn't look too hard to do this:
>
> Use call_usermodehelper_fns with an "init" function that changes the
> namespace(s) of the process before the do_execve call. The namespace
> info could be passed in via the "data" parm to call_usermodehelper_fns.
> Alternately, I guess you could add some namespace fields to struct
> subprocess_info...
>
> That said, I'm not clear on how you have to go about changing the
> namespace once the new process has been spawned...
>

Thanks, Jeff.

>
>>> Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
>>> Signed-off-by: Jeff Layton <jlayton@redhat.com>
>>> ---
>>>    fs/nfsd/nfs4recover.c          | 492 +----------------------------------------
>>>    fs/nfsd/nfsctl.c               |   8 +-
>>>    fs/nfsd/nfsd.h                 |   5 -
>>>    include/uapi/linux/nfsd/Kbuild |   1 -
>>>    include/uapi/linux/nfsd/cld.h  |  56 -----
>>>    5 files changed, 6 insertions(+), 556 deletions(-)
>>>    delete mode 100644 include/uapi/linux/nfsd/cld.h
>>>
>>> diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
>>> index 899ca26..4e7f47e 100644
>>> --- a/fs/nfsd/nfs4recover.c
>>> +++ b/fs/nfsd/nfs4recover.c
>>> @@ -42,7 +42,6 @@
>>>    #include <net/net_namespace.h>
>>>    #include <linux/sunrpc/rpc_pipe_fs.h>
>>>    #include <linux/sunrpc/clnt.h>
>>> -#include <linux/nfsd/cld.h>
>>>
>>>    #include "nfsd.h"
>>>    #include "state.h"
>>> @@ -625,426 +624,6 @@ static struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = {
>>>    	.grace_done	= nfsd4_recdir_purge_old,
>>>    };
>>>
>>> -/* Globals */
>>> -#define NFSD_PIPE_DIR		"nfsd"
>>> -#define NFSD_CLD_PIPE		"cld"
>>> -
>>> -/* per-net-ns structure for holding cld upcall info */
>>> -struct cld_net {
>>> -	struct rpc_pipe		*cn_pipe;
>>> -	spinlock_t		 cn_lock;
>>> -	struct list_head	 cn_list;
>>> -	unsigned int		 cn_xid;
>>> -};
>>> -
>>> -struct cld_upcall {
>>> -	struct list_head	 cu_list;
>>> -	struct cld_net		*cu_net;
>>> -	struct task_struct	*cu_task;
>>> -	struct cld_msg		 cu_msg;
>>> -};
>>> -
>>> -static int
>>> -__cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg)
>>> -{
>>> -	int ret;
>>> -	struct rpc_pipe_msg msg;
>>> -
>>> -	memset(&msg, 0, sizeof(msg));
>>> -	msg.data = cmsg;
>>> -	msg.len = sizeof(*cmsg);
>>> -
>>> -	/*
>>> -	 * Set task state before we queue the upcall. That prevents
>>> -	 * wake_up_process in the downcall from racing with schedule.
>>> -	 */
>>> -	set_current_state(TASK_UNINTERRUPTIBLE);
>>> -	ret = rpc_queue_upcall(pipe, &msg);
>>> -	if (ret < 0) {
>>> -		set_current_state(TASK_RUNNING);
>>> -		goto out;
>>> -	}
>>> -
>>> -	schedule();
>>> -	set_current_state(TASK_RUNNING);
>>> -
>>> -	if (msg.errno < 0)
>>> -		ret = msg.errno;
>>> -out:
>>> -	return ret;
>>> -}
>>> -
>>> -static int
>>> -cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg)
>>> -{
>>> -	int ret;
>>> -
>>> -	/*
>>> -	 * -EAGAIN occurs when pipe is closed and reopened while there are
>>> -	 *  upcalls queued.
>>> -	 */
>>> -	do {
>>> -		ret = __cld_pipe_upcall(pipe, cmsg);
>>> -	} while (ret == -EAGAIN);
>>> -
>>> -	return ret;
>>> -}
>>> -
>>> -static ssize_t
>>> -cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
>>> -{
>>> -	struct cld_upcall *tmp, *cup;
>>> -	struct cld_msg __user *cmsg = (struct cld_msg __user *)src;
>>> -	uint32_t xid;
>>> -	struct nfsd_net *nn = net_generic(filp->f_dentry->d_sb->s_fs_info,
>>> -						nfsd_net_id);
>>> -	struct cld_net *cn = nn->cld_net;
>>> -
>>> -	if (mlen != sizeof(*cmsg)) {
>>> -		dprintk("%s: got %zu bytes, expected %zu\n", __func__, mlen,
>>> -			sizeof(*cmsg));
>>> -		return -EINVAL;
>>> -	}
>>> -
>>> -	/* copy just the xid so we can try to find that */
>>> -	if (copy_from_user(&xid, &cmsg->cm_xid, sizeof(xid)) != 0) {
>>> -		dprintk("%s: error when copying xid from userspace", __func__);
>>> -		return -EFAULT;
>>> -	}
>>> -
>>> -	/* walk the list and find corresponding xid */
>>> -	cup = NULL;
>>> -	spin_lock(&cn->cn_lock);
>>> -	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
>>> -		if (get_unaligned(&tmp->cu_msg.cm_xid) == xid) {
>>> -			cup = tmp;
>>> -			list_del_init(&cup->cu_list);
>>> -			break;
>>> -		}
>>> -	}
>>> -	spin_unlock(&cn->cn_lock);
>>> -
>>> -	/* couldn't find upcall? */
>>> -	if (!cup) {
>>> -		dprintk("%s: couldn't find upcall -- xid=%u\n", __func__, xid);
>>> -		return -EINVAL;
>>> -	}
>>> -
>>> -	if (copy_from_user(&cup->cu_msg, src, mlen) != 0)
>>> -		return -EFAULT;
>>> -
>>> -	wake_up_process(cup->cu_task);
>>> -	return mlen;
>>> -}
>>> -
>>> -static void
>>> -cld_pipe_destroy_msg(struct rpc_pipe_msg *msg)
>>> -{
>>> -	struct cld_msg *cmsg = msg->data;
>>> -	struct cld_upcall *cup = container_of(cmsg, struct cld_upcall,
>>> -						 cu_msg);
>>> -
>>> -	/* errno >= 0 means we got a downcall */
>>> -	if (msg->errno >= 0)
>>> -		return;
>>> -
>>> -	wake_up_process(cup->cu_task);
>>> -}
>>> -
>>> -static const struct rpc_pipe_ops cld_upcall_ops = {
>>> -	.upcall		= rpc_pipe_generic_upcall,
>>> -	.downcall	= cld_pipe_downcall,
>>> -	.destroy_msg	= cld_pipe_destroy_msg,
>>> -};
>>> -
>>> -static struct dentry *
>>> -nfsd4_cld_register_sb(struct super_block *sb, struct rpc_pipe *pipe)
>>> -{
>>> -	struct dentry *dir, *dentry;
>>> -
>>> -	dir = rpc_d_lookup_sb(sb, NFSD_PIPE_DIR);
>>> -	if (dir == NULL)
>>> -		return ERR_PTR(-ENOENT);
>>> -	dentry = rpc_mkpipe_dentry(dir, NFSD_CLD_PIPE, NULL, pipe);
>>> -	dput(dir);
>>> -	return dentry;
>>> -}
>>> -
>>> -static void
>>> -nfsd4_cld_unregister_sb(struct rpc_pipe *pipe)
>>> -{
>>> -	if (pipe->dentry)
>>> -		rpc_unlink(pipe->dentry);
>>> -}
>>> -
>>> -static struct dentry *
>>> -nfsd4_cld_register_net(struct net *net, struct rpc_pipe *pipe)
>>> -{
>>> -	struct super_block *sb;
>>> -	struct dentry *dentry;
>>> -
>>> -	sb = rpc_get_sb_net(net);
>>> -	if (!sb)
>>> -		return NULL;
>>> -	dentry = nfsd4_cld_register_sb(sb, pipe);
>>> -	rpc_put_sb_net(net);
>>> -	return dentry;
>>> -}
>>> -
>>> -static void
>>> -nfsd4_cld_unregister_net(struct net *net, struct rpc_pipe *pipe)
>>> -{
>>> -	struct super_block *sb;
>>> -
>>> -	sb = rpc_get_sb_net(net);
>>> -	if (sb) {
>>> -		nfsd4_cld_unregister_sb(pipe);
>>> -		rpc_put_sb_net(net);
>>> -	}
>>> -}
>>> -
>>> -/* Initialize rpc_pipefs pipe for communication with client tracking daemon */
>>> -static int
>>> -nfsd4_init_cld_pipe(struct net *net)
>>> -{
>>> -	int ret;
>>> -	struct dentry *dentry;
>>> -	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
>>> -	struct cld_net *cn;
>>> -
>>> -	if (nn->cld_net)
>>> -		return 0;
>>> -
>>> -	cn = kzalloc(sizeof(*cn), GFP_KERNEL);
>>> -	if (!cn) {
>>> -		ret = -ENOMEM;
>>> -		goto err;
>>> -	}
>>> -
>>> -	cn->cn_pipe = rpc_mkpipe_data(&cld_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
>>> -	if (IS_ERR(cn->cn_pipe)) {
>>> -		ret = PTR_ERR(cn->cn_pipe);
>>> -		goto err;
>>> -	}
>>> -	spin_lock_init(&cn->cn_lock);
>>> -	INIT_LIST_HEAD(&cn->cn_list);
>>> -
>>> -	dentry = nfsd4_cld_register_net(net, cn->cn_pipe);
>>> -	if (IS_ERR(dentry)) {
>>> -		ret = PTR_ERR(dentry);
>>> -		goto err_destroy_data;
>>> -	}
>>> -
>>> -	cn->cn_pipe->dentry = dentry;
>>> -	nn->cld_net = cn;
>>> -	return 0;
>>> -
>>> -err_destroy_data:
>>> -	rpc_destroy_pipe_data(cn->cn_pipe);
>>> -err:
>>> -	kfree(cn);
>>> -	printk(KERN_ERR "NFSD: unable to create nfsdcld upcall pipe (%d)\n",
>>> -			ret);
>>> -	return ret;
>>> -}
>>> -
>>> -static void
>>> -nfsd4_remove_cld_pipe(struct net *net)
>>> -{
>>> -	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
>>> -	struct cld_net *cn = nn->cld_net;
>>> -
>>> -	nfsd4_cld_unregister_net(net, cn->cn_pipe);
>>> -	rpc_destroy_pipe_data(cn->cn_pipe);
>>> -	kfree(nn->cld_net);
>>> -	nn->cld_net = NULL;
>>> -}
>>> -
>>> -static struct cld_upcall *
>>> -alloc_cld_upcall(struct cld_net *cn)
>>> -{
>>> -	struct cld_upcall *new, *tmp;
>>> -
>>> -	new = kzalloc(sizeof(*new), GFP_KERNEL);
>>> -	if (!new)
>>> -		return new;
>>> -
>>> -	/* FIXME: hard cap on number in flight? */
>>> -restart_search:
>>> -	spin_lock(&cn->cn_lock);
>>> -	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
>>> -		if (tmp->cu_msg.cm_xid == cn->cn_xid) {
>>> -			cn->cn_xid++;
>>> -			spin_unlock(&cn->cn_lock);
>>> -			goto restart_search;
>>> -		}
>>> -	}
>>> -	new->cu_task = current;
>>> -	new->cu_msg.cm_vers = CLD_UPCALL_VERSION;
>>> -	put_unaligned(cn->cn_xid++, &new->cu_msg.cm_xid);
>>> -	new->cu_net = cn;
>>> -	list_add(&new->cu_list, &cn->cn_list);
>>> -	spin_unlock(&cn->cn_lock);
>>> -
>>> -	dprintk("%s: allocated xid %u\n", __func__, new->cu_msg.cm_xid);
>>> -
>>> -	return new;
>>> -}
>>> -
>>> -static void
>>> -free_cld_upcall(struct cld_upcall *victim)
>>> -{
>>> -	struct cld_net *cn = victim->cu_net;
>>> -
>>> -	spin_lock(&cn->cn_lock);
>>> -	list_del(&victim->cu_list);
>>> -	spin_unlock(&cn->cn_lock);
>>> -	kfree(victim);
>>> -}
>>> -
>>> -/* Ask daemon to create a new record */
>>> -static void
>>> -nfsd4_cld_create(struct nfs4_client *clp)
>>> -{
>>> -	int ret;
>>> -	struct cld_upcall *cup;
>>> -	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
>>> -	struct cld_net *cn = nn->cld_net;
>>> -
>>> -	/* Don't upcall if it's already stored */
>>> -	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
>>> -		return;
>>> -
>>> -	cup = alloc_cld_upcall(cn);
>>> -	if (!cup) {
>>> -		ret = -ENOMEM;
>>> -		goto out_err;
>>> -	}
>>> -
>>> -	cup->cu_msg.cm_cmd = Cld_Create;
>>> -	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
>>> -	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
>>> -			clp->cl_name.len);
>>> -
>>> -	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
>>> -	if (!ret) {
>>> -		ret = cup->cu_msg.cm_status;
>>> -		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
>>> -	}
>>> -
>>> -	free_cld_upcall(cup);
>>> -out_err:
>>> -	if (ret)
>>> -		printk(KERN_ERR "NFSD: Unable to create client "
>>> -				"record on stable storage: %d\n", ret);
>>> -}
>>> -
>>> -/* Ask daemon to create a new record */
>>> -static void
>>> -nfsd4_cld_remove(struct nfs4_client *clp)
>>> -{
>>> -	int ret;
>>> -	struct cld_upcall *cup;
>>> -	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
>>> -	struct cld_net *cn = nn->cld_net;
>>> -
>>> -	/* Don't upcall if it's already removed */
>>> -	if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
>>> -		return;
>>> -
>>> -	cup = alloc_cld_upcall(cn);
>>> -	if (!cup) {
>>> -		ret = -ENOMEM;
>>> -		goto out_err;
>>> -	}
>>> -
>>> -	cup->cu_msg.cm_cmd = Cld_Remove;
>>> -	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
>>> -	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
>>> -			clp->cl_name.len);
>>> -
>>> -	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
>>> -	if (!ret) {
>>> -		ret = cup->cu_msg.cm_status;
>>> -		clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
>>> -	}
>>> -
>>> -	free_cld_upcall(cup);
>>> -out_err:
>>> -	if (ret)
>>> -		printk(KERN_ERR "NFSD: Unable to remove client "
>>> -				"record from stable storage: %d\n", ret);
>>> -}
>>> -
>>> -/* Check for presence of a record, and update its timestamp */
>>> -static int
>>> -nfsd4_cld_check(struct nfs4_client *clp)
>>> -{
>>> -	int ret;
>>> -	struct cld_upcall *cup;
>>> -	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
>>> -	struct cld_net *cn = nn->cld_net;
>>> -
>>> -	/* Don't upcall if one was already stored during this grace pd */
>>> -	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
>>> -		return 0;
>>> -
>>> -	cup = alloc_cld_upcall(cn);
>>> -	if (!cup) {
>>> -		printk(KERN_ERR "NFSD: Unable to check client record on "
>>> -				"stable storage: %d\n", -ENOMEM);
>>> -		return -ENOMEM;
>>> -	}
>>> -
>>> -	cup->cu_msg.cm_cmd = Cld_Check;
>>> -	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
>>> -	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
>>> -			clp->cl_name.len);
>>> -
>>> -	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
>>> -	if (!ret) {
>>> -		ret = cup->cu_msg.cm_status;
>>> -		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
>>> -	}
>>> -
>>> -	free_cld_upcall(cup);
>>> -	return ret;
>>> -}
>>> -
>>> -static void
>>> -nfsd4_cld_grace_done(struct nfsd_net *nn, time_t boot_time)
>>> -{
>>> -	int ret;
>>> -	struct cld_upcall *cup;
>>> -	struct cld_net *cn = nn->cld_net;
>>> -
>>> -	cup = alloc_cld_upcall(cn);
>>> -	if (!cup) {
>>> -		ret = -ENOMEM;
>>> -		goto out_err;
>>> -	}
>>> -
>>> -	cup->cu_msg.cm_cmd = Cld_GraceDone;
>>> -	cup->cu_msg.cm_u.cm_gracetime = (int64_t)boot_time;
>>> -	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
>>> -	if (!ret)
>>> -		ret = cup->cu_msg.cm_status;
>>> -
>>> -	free_cld_upcall(cup);
>>> -out_err:
>>> -	if (ret)
>>> -		printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret);
>>> -}
>>> -
>>> -static struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = {
>>> -	.init		= nfsd4_init_cld_pipe,
>>> -	.exit		= nfsd4_remove_cld_pipe,
>>> -	.create		= nfsd4_cld_create,
>>> -	.remove		= nfsd4_cld_remove,
>>> -	.check		= nfsd4_cld_check,
>>> -	.grace_done	= nfsd4_cld_grace_done,
>>> -};
>>> -
>>>    /* upcall via usermodehelper */
>>>    static char cltrack_prog[PATH_MAX] = "/sbin/nfsdcltrack";
>>>    module_param_string(cltrack_prog, cltrack_prog, sizeof(cltrack_prog),
>>> @@ -1287,21 +866,14 @@ nfsd4_client_tracking_init(struct net *net)
>>>    	 * then use the legacy ops.
>>>    	 */
>>>    	nn->client_tracking_ops = &nfsd4_legacy_tracking_ops;
>>> -	status = kern_path(nfs4_recoverydir(), LOOKUP_FOLLOW, &path);
>>> -	if (!status) {
>>> -		status = S_ISDIR(path.dentry->d_inode->i_mode);
>>> -		path_put(&path);
>>> -		if (status)
>>> -			goto do_init;
>>> -	}
>>> +	status = kern_path(nfs4_recoverydir(),
>>> +				LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &path);
>>> +	if (status)
>>> +		goto out_err;
>>>
>>> -	/* Finally, try to use nfsdcld */
>>> -	nn->client_tracking_ops = &nfsd4_cld_tracking_ops;
>>> -	printk(KERN_WARNING "NFSD: the nfsdcld client tracking upcall will be "
>>> -			"removed in 3.10. Please transition to using "
>>> -			"nfsdcltrack.\n");
>>>    do_init:
>>>    	status = nn->client_tracking_ops->init(net);
>>> +out_err:
>>>    	if (status) {
>>>    		printk(KERN_WARNING "NFSD: Unable to initialize client "
>>>    				    "recovery tracking! (%d)\n", status);
>>> @@ -1358,57 +930,3 @@ nfsd4_record_grace_done(struct nfsd_net *nn, time_t boot_time)
>>>    		nn->client_tracking_ops->grace_done(nn, boot_time);
>>>    }
>>>
>>> -static int
>>> -rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr)
>>> -{
>>> -	struct super_block *sb = ptr;
>>> -	struct net *net = sb->s_fs_info;
>>> -	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
>>> -	struct cld_net *cn = nn->cld_net;
>>> -	struct dentry *dentry;
>>> -	int ret = 0;
>>> -
>>> -	if (!try_module_get(THIS_MODULE))
>>> -		return 0;
>>> -
>>> -	if (!cn) {
>>> -		module_put(THIS_MODULE);
>>> -		return 0;
>>> -	}
>>> -
>>> -	switch (event) {
>>> -	case RPC_PIPEFS_MOUNT:
>>> -		dentry = nfsd4_cld_register_sb(sb, cn->cn_pipe);
>>> -		if (IS_ERR(dentry)) {
>>> -			ret = PTR_ERR(dentry);
>>> -			break;
>>> -		}
>>> -		cn->cn_pipe->dentry = dentry;
>>> -		break;
>>> -	case RPC_PIPEFS_UMOUNT:
>>> -		if (cn->cn_pipe->dentry)
>>> -			nfsd4_cld_unregister_sb(cn->cn_pipe);
>>> -		break;
>>> -	default:
>>> -		ret = -ENOTSUPP;
>>> -		break;
>>> -	}
>>> -	module_put(THIS_MODULE);
>>> -	return ret;
>>> -}
>>> -
>>> -static struct notifier_block nfsd4_cld_block = {
>>> -	.notifier_call = rpc_pipefs_event,
>>> -};
>>> -
>>> -int
>>> -register_cld_notifier(void)
>>> -{
>>> -	return rpc_pipefs_notifier_register(&nfsd4_cld_block);
>>> -}
>>> -
>>> -void
>>> -unregister_cld_notifier(void)
>>> -{
>>> -	rpc_pipefs_notifier_unregister(&nfsd4_cld_block);
>>> -}
>>> diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
>>> index a830f33..f0aeb93 100644
>>> --- a/fs/nfsd/nfsctl.c
>>> +++ b/fs/nfsd/nfsctl.c
>>> @@ -1163,12 +1163,9 @@ static int __init init_nfsd(void)
>>>    	int retval;
>>>    	printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
>>>
>>> -	retval = register_cld_notifier();
>>> -	if (retval)
>>> -		return retval;
>>>    	retval = register_pernet_subsys(&nfsd_net_ops);
>>>    	if (retval < 0)
>>> -		goto out_unregister_notifier;
>>> +		return retval;
>>>    	retval = nfsd4_init_slabs();
>>>    	if (retval)
>>>    		goto out_unregister_pernet;
>>> @@ -1201,8 +1198,6 @@ out_free_slabs:
>>>    	nfsd4_free_slabs();
>>>    out_unregister_pernet:
>>>    	unregister_pernet_subsys(&nfsd_net_ops);
>>> -out_unregister_notifier:
>>> -	unregister_cld_notifier();
>>>    	return retval;
>>>    }
>>>
>>> @@ -1217,7 +1212,6 @@ static void __exit exit_nfsd(void)
>>>    	nfsd_fault_inject_cleanup();
>>>    	unregister_filesystem(&nfsd_fs_type);
>>>    	unregister_pernet_subsys(&nfsd_net_ops);
>>> -	unregister_cld_notifier();
>>>    }
>>>
>>>    MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
>>> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
>>> index 07a473f..8eb2aac 100644
>>> --- a/fs/nfsd/nfsd.h
>>> +++ b/fs/nfsd/nfsd.h
>>> @@ -365,17 +365,12 @@ static inline u32 nfsd_suppattrs2(u32 minorversion)
>>>    	NFSD_WRITEABLE_ATTRS_WORD2
>>>
>>>    extern int nfsd4_is_junction(struct dentry *dentry);
>>> -extern int register_cld_notifier(void);
>>> -extern void unregister_cld_notifier(void);
>>>    #else /* CONFIG_NFSD_V4 */
>>>    static inline int nfsd4_is_junction(struct dentry *dentry)
>>>    {
>>>    	return 0;
>>>    }
>>>
>>> -#define register_cld_notifier() 0
>>> -#define unregister_cld_notifier() do { } while(0)
>>> -
>>>    #endif /* CONFIG_NFSD_V4 */
>>>
>>>    #endif /* LINUX_NFSD_NFSD_H */
>>> diff --git a/include/uapi/linux/nfsd/Kbuild b/include/uapi/linux/nfsd/Kbuild
>>> index c11bc40..88589ac 100644
>>> --- a/include/uapi/linux/nfsd/Kbuild
>>> +++ b/include/uapi/linux/nfsd/Kbuild
>>> @@ -1,5 +1,4 @@
>>>    # UAPI Header export list
>>> -header-y += cld.h
>>>    header-y += debug.h
>>>    header-y += export.h
>>>    header-y += nfsfh.h
>>> diff --git a/include/uapi/linux/nfsd/cld.h b/include/uapi/linux/nfsd/cld.h
>>> deleted file mode 100644
>>> index f14a9ab..0000000
>>> --- a/include/uapi/linux/nfsd/cld.h
>>> +++ /dev/null
>>> @@ -1,56 +0,0 @@
>>> -/*
>>> - * Upcall description for nfsdcld communication
>>> - *
>>> - * Copyright (c) 2012 Red Hat, Inc.
>>> - * Author(s): Jeff Layton <jlayton@redhat.com>
>>> - *
>>> - *  This program is free software; you can redistribute it and/or modify
>>> - *  it under the terms of the GNU General Public License as published by
>>> - *  the Free Software Foundation; either version 2 of the License, or
>>> - *  (at your option) any later version.
>>> - *
>>> - *  This program is distributed in the hope that it will be useful,
>>> - *  but WITHOUT ANY WARRANTY; without even the implied warranty of
>>> - *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>>> - *  GNU General Public License for more details.
>>> - *
>>> - *  You should have received a copy of the GNU General Public License
>>> - *  along with this program; if not, write to the Free Software
>>> - *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
>>> - */
>>> -
>>> -#ifndef _NFSD_CLD_H
>>> -#define _NFSD_CLD_H
>>> -
>>> -/* latest upcall version available */
>>> -#define CLD_UPCALL_VERSION 1
>>> -
>>> -/* defined by RFC3530 */
>>> -#define NFS4_OPAQUE_LIMIT 1024
>>> -
>>> -enum cld_command {
>>> -	Cld_Create,		/* create a record for this cm_id */
>>> -	Cld_Remove,		/* remove record of this cm_id */
>>> -	Cld_Check,		/* is this cm_id allowed? */
>>> -	Cld_GraceDone,		/* grace period is complete */
>>> -};
>>> -
>>> -/* representation of long-form NFSv4 client ID */
>>> -struct cld_name {
>>> -	uint16_t	cn_len;				/* length of cm_id */
>>> -	unsigned char	cn_id[NFS4_OPAQUE_LIMIT];	/* client-provided */
>>> -} __attribute__((packed));
>>> -
>>> -/* message struct for communication with userspace */
>>> -struct cld_msg {
>>> -	uint8_t		cm_vers;		/* upcall version */
>>> -	uint8_t		cm_cmd;			/* upcall command */
>>> -	int16_t		cm_status;		/* return code */
>>> -	uint32_t	cm_xid;			/* transaction id */
>>> -	union {
>>> -		int64_t		cm_gracetime;	/* grace period start time */
>>> -		struct cld_name	cm_name;
>>> -	} __attribute__((packed)) cm_u;
>>> -} __attribute__((packed));
>>> -
>>> -#endif /* !_NFSD_CLD_H */
>>>
>>
>>
>
>


-- 
Best regards,
Stanislav Kinsbursky