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Message-ID: <2a59c1ce7320af8d645540522c87ae1b44f76a3d.camel@kernel.org>
Subject: Re: [PATCH v6 2/3] NFSD: add write_version to netlink command
From: Jeff Layton <jlayton@kernel.org>
To: Lorenzo Bianconi <lorenzo@kernel.org>, linux-nfs@vger.kernel.org
Cc: lorenzo.bianconi@redhat.com, neilb@suse.de, kuba@kernel.org, 
	chuck.lever@oracle.com, horms@kernel.org, netdev@vger.kernel.org
Date: Mon, 22 Jan 2024 08:27:01 -0500
In-Reply-To: <fd54905f4d66b84afbc9a8270261d27ad509f0a0.1705771400.git.lorenzo@kernel.org>
References: <cover.1705771400.git.lorenzo@kernel.org>
	 <fd54905f4d66b84afbc9a8270261d27ad509f0a0.1705771400.git.lorenzo@kernel.org>
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On Sat, 2024-01-20 at 18:33 +0100, Lorenzo Bianconi wrote:
> Introduce write_version netlink command. For version-set, userspace is
> expected to provide a NFS major/minor version list it wants to enable
> (all the other ones will be disabled).
>=20

To be clear, this is a departure from how the existing interface works.
The "versions" file was an imperative interface. You write "+3" to it,
and that just enables v3.

This is a declarative interface. If a version is not listed in the set,
then it will be _disabled_. I think this is a better way to do it, given
the way that rpc.nfsd works, but we should all be aware that this is a
change in behavior.

> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
> ---
>  Documentation/netlink/specs/nfsd.yaml |  34 +++++
>  fs/nfsd/netlink.c                     |  23 ++++
>  fs/nfsd/netlink.h                     |   5 +
>  fs/nfsd/nfsctl.c                      | 140 ++++++++++++++++++++
>  include/uapi/linux/nfsd_netlink.h     |  17 +++
>  tools/net/ynl/generated/nfsd-user.c   | 176 ++++++++++++++++++++++++++
>  tools/net/ynl/generated/nfsd-user.h   |  53 ++++++++
>  7 files changed, 448 insertions(+)
>=20
> diff --git a/Documentation/netlink/specs/nfsd.yaml b/Documentation/netlin=
k/specs/nfsd.yaml
> index c92e1425d316..30f18798e84e 100644
> --- a/Documentation/netlink/specs/nfsd.yaml
> +++ b/Documentation/netlink/specs/nfsd.yaml
> @@ -68,6 +68,23 @@ attribute-sets:
>        -
>          name: threads
>          type: u32
> +  -
> +    name: nfs-version
> +    attributes:
> +      -
> +        name: major
> +        type: u32
> +      -
> +        name: minor
> +        type: u32
> +  -
> +    name: server-proto
> +    attributes:
> +      -
> +        name: version
> +        type: nest
> +        nested-attributes: nfs-version
> +        multi-attr: true
> =20
>  operations:
>    list:
> @@ -110,3 +127,20 @@ operations:
>          reply:
>            attributes:
>              - threads
> +    -
> +      name: version-set
> +      doc: set nfs enabled versions
> +      attribute-set: server-proto
> +      flags: [ admin-perm ]
> +      do:
> +        request:
> +          attributes:
> +            - version
> +    -
> +      name: version-get
> +      doc: get nfs enabled versions
> +      attribute-set: server-proto
> +      do:
> +        reply:
> +          attributes:
> +            - version
> diff --git a/fs/nfsd/netlink.c b/fs/nfsd/netlink.c
> index 1a59a8e6c7e2..5cbbd3295543 100644
> --- a/fs/nfsd/netlink.c
> +++ b/fs/nfsd/netlink.c
> @@ -10,11 +10,22 @@
> =20
>  #include <uapi/linux/nfsd_netlink.h>
> =20
> +/* Common nested types */
> +const struct nla_policy nfsd_nfs_version_nl_policy[NFSD_A_NFS_VERSION_MI=
NOR + 1] =3D {
> +	[NFSD_A_NFS_VERSION_MAJOR] =3D { .type =3D NLA_U32, },
> +	[NFSD_A_NFS_VERSION_MINOR] =3D { .type =3D NLA_U32, },
> +};
> +
>  /* NFSD_CMD_THREADS_SET - do */
>  static const struct nla_policy nfsd_threads_set_nl_policy[NFSD_A_SERVER_=
WORKER_THREADS + 1] =3D {
>  	[NFSD_A_SERVER_WORKER_THREADS] =3D { .type =3D NLA_U32, },
>  };
> =20
> +/* NFSD_CMD_VERSION_SET - do */
> +static const struct nla_policy nfsd_version_set_nl_policy[NFSD_A_SERVER_=
PROTO_VERSION + 1] =3D {
> +	[NFSD_A_SERVER_PROTO_VERSION] =3D NLA_POLICY_NESTED(nfsd_nfs_version_nl=
_policy),
> +};
> +
>  /* Ops table for nfsd */
>  static const struct genl_split_ops nfsd_nl_ops[] =3D {
>  	{
> @@ -36,6 +47,18 @@ static const struct genl_split_ops nfsd_nl_ops[] =3D {
>  		.doit	=3D nfsd_nl_threads_get_doit,
>  		.flags	=3D GENL_CMD_CAP_DO,
>  	},
> +	{
> +		.cmd		=3D NFSD_CMD_VERSION_SET,
> +		.doit		=3D nfsd_nl_version_set_doit,
> +		.policy		=3D nfsd_version_set_nl_policy,
> +		.maxattr	=3D NFSD_A_SERVER_PROTO_VERSION,
> +		.flags		=3D GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
> +	},
> +	{
> +		.cmd	=3D NFSD_CMD_VERSION_GET,
> +		.doit	=3D nfsd_nl_version_get_doit,
> +		.flags	=3D GENL_CMD_CAP_DO,
> +	},
>  };
> =20
>  struct genl_family nfsd_nl_family __ro_after_init =3D {
> diff --git a/fs/nfsd/netlink.h b/fs/nfsd/netlink.h
> index 4137fac477e4..c9a1be693fef 100644
> --- a/fs/nfsd/netlink.h
> +++ b/fs/nfsd/netlink.h
> @@ -11,6 +11,9 @@
> =20
>  #include <uapi/linux/nfsd_netlink.h>
> =20
> +/* Common nested types */
> +extern const struct nla_policy nfsd_nfs_version_nl_policy[NFSD_A_NFS_VER=
SION_MINOR + 1];
> +
>  int nfsd_nl_rpc_status_get_start(struct netlink_callback *cb);
>  int nfsd_nl_rpc_status_get_done(struct netlink_callback *cb);
> =20
> @@ -18,6 +21,8 @@ int nfsd_nl_rpc_status_get_dumpit(struct sk_buff *skb,
>  				  struct netlink_callback *cb);
>  int nfsd_nl_threads_set_doit(struct sk_buff *skb, struct genl_info *info=
);
>  int nfsd_nl_threads_get_doit(struct sk_buff *skb, struct genl_info *info=
);
> +int nfsd_nl_version_set_doit(struct sk_buff *skb, struct genl_info *info=
);
> +int nfsd_nl_version_get_doit(struct sk_buff *skb, struct genl_info *info=
);
> =20
>  extern struct genl_family nfsd_nl_family;
> =20
> diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
> index 68718448d660..53af82303f93 100644
> --- a/fs/nfsd/nfsctl.c
> +++ b/fs/nfsd/nfsctl.c
> @@ -1756,6 +1756,146 @@ int nfsd_nl_threads_get_doit(struct sk_buff *skb,=
 struct genl_info *info)
>  	return err;
>  }
> =20
> +/**
> + * nfsd_nl_version_set_doit - set the nfs enabled versions
> + * @skb: reply buffer
> + * @info: netlink metadata and command arguments
> + *
> + * Return 0 on success or a negative errno.
> + */
> +int nfsd_nl_version_set_doit(struct sk_buff *skb, struct genl_info *info=
)
> +{
> +	const struct nlattr *attr;
> +	struct nfsd_net *nn;
> +	int i, rem;
> +
> +	if (GENL_REQ_ATTR_CHECK(info, NFSD_A_SERVER_PROTO_VERSION))
> +		return -EINVAL;
> +
> +	mutex_lock(&nfsd_mutex);
> +
> +	nn =3D net_generic(genl_info_net(info), nfsd_net_id);
> +	if (nn->nfsd_serv) {
> +		mutex_unlock(&nfsd_mutex);
> +		return -EBUSY;
> +	}
> +
> +	/* clear current supported versions. */
> +	nfsd_vers(nn, 2, NFSD_CLEAR);
> +	nfsd_vers(nn, 3, NFSD_CLEAR);
> +	for (i =3D 0; i <=3D NFSD_SUPPORTED_MINOR_VERSION; i++)
> +		nfsd_minorversion(nn, i, NFSD_CLEAR);
> +
> +	nlmsg_for_each_attr(attr, info->nlhdr, GENL_HDRLEN, rem) {
> +		struct nlattr *tb[ARRAY_SIZE(nfsd_nfs_version_nl_policy)];
> +		u32 major, minor =3D 0;
> +
> +		if (nla_type(attr) !=3D NFSD_A_SERVER_PROTO_VERSION)
> +			continue;
> +
> +		if (nla_parse_nested(tb, ARRAY_SIZE(tb), attr,
> +				     nfsd_nfs_version_nl_policy,
> +				     info->extack) < 0)
> +			continue;
> +
> +		if (!tb[NFSD_A_NFS_VERSION_MAJOR])
> +			continue;
> +
> +		major =3D nla_get_u32(tb[NFSD_A_NFS_VERSION_MAJOR]);
> +		if (tb[NFSD_A_NFS_VERSION_MINOR])
> +			minor =3D nla_get_u32(tb[NFSD_A_NFS_VERSION_MINOR]);
> +
> +		switch (major) {
> +		case 4:
> +			nfsd_minorversion(nn, minor, NFSD_SET);
> +			break;
> +		case 3:
> +		case 2:
> +			if (!minor)
> +				nfsd_vers(nn, major, NFSD_SET);
> +			break;
> +		default:
> +			break;
> +		}
> +	}
> +
> +	mutex_unlock(&nfsd_mutex);
> +
> +	return 0;
> +}
> +
> +/**
> + * nfsd_nl_version_get_doit - get the nfs enabled versions
> + * @skb: reply buffer
> + * @info: netlink metadata and command arguments
> + *
> + * Return 0 on success or a negative errno.
> + */
> +int nfsd_nl_version_get_doit(struct sk_buff *skb, struct genl_info *info=
)
> +{
> +	struct nfsd_net *nn;
> +	int i, err;
> +	void *hdr;
> +
> +	skb =3D genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
> +	if (!skb)
> +		return -ENOMEM;
> +
> +	hdr =3D genlmsg_iput(skb, info);
> +	if (!hdr) {
> +		err =3D -EMSGSIZE;
> +		goto err_free_msg;
> +	}
> +
> +	mutex_lock(&nfsd_mutex);
> +	nn =3D net_generic(genl_info_net(info), nfsd_net_id);
> +
> +	for (i =3D 2; i <=3D 4; i++) {
> +		int j;
> +
> +		for (j =3D 0; j <=3D NFSD_SUPPORTED_MINOR_VERSION; j++) {
> +			struct nlattr *attr;
> +
> +			if (!nfsd_vers(nn, i, NFSD_TEST))
> +				continue;
> +
> +			/* NFSv{2,3} does not support minor numbers */
> +			if (i < 4 && j)
> +				continue;
> +
> +			if (i =3D=3D 4 && !nfsd_minorversion(nn, j, NFSD_TEST))
> +				continue;
> +
> +			attr =3D nla_nest_start_noflag(skb,
> +					NFSD_A_SERVER_PROTO_VERSION);
> +			if (!attr) {
> +				err =3D -EINVAL;
> +				goto err_nfsd_unlock;
> +			}
> +
> +			if (nla_put_u32(skb, NFSD_A_NFS_VERSION_MAJOR, i) ||
> +			    nla_put_u32(skb, NFSD_A_NFS_VERSION_MINOR, j)) {
> +				err =3D -EINVAL;
> +				goto err_nfsd_unlock;
> +			}
> +
> +			nla_nest_end(skb, attr);
> +		}
> +	}
> +
> +	mutex_unlock(&nfsd_mutex);
> +	genlmsg_end(skb, hdr);
> +
> +	return genlmsg_reply(skb, info);
> +
> +err_nfsd_unlock:
> +	mutex_unlock(&nfsd_mutex);
> +err_free_msg:
> +	nlmsg_free(skb);
> +
> +	return err;
> +}
> +
>  /**
>   * nfsd_net_init - Prepare the nfsd_net portion of a new net namespace
>   * @net: a freshly-created network namespace
> diff --git a/include/uapi/linux/nfsd_netlink.h b/include/uapi/linux/nfsd_=
netlink.h
> index 1b6fe1f9ed0e..2a06f9fe6fe9 100644
> --- a/include/uapi/linux/nfsd_netlink.h
> +++ b/include/uapi/linux/nfsd_netlink.h
> @@ -36,10 +36,27 @@ enum {
>  	NFSD_A_SERVER_WORKER_MAX =3D (__NFSD_A_SERVER_WORKER_MAX - 1)
>  };
> =20
> +enum {
> +	NFSD_A_NFS_VERSION_MAJOR =3D 1,
> +	NFSD_A_NFS_VERSION_MINOR,
> +
> +	__NFSD_A_NFS_VERSION_MAX,
> +	NFSD_A_NFS_VERSION_MAX =3D (__NFSD_A_NFS_VERSION_MAX - 1)
> +};
> +
> +enum {
> +	NFSD_A_SERVER_PROTO_VERSION =3D 1,
> +
> +	__NFSD_A_SERVER_PROTO_MAX,
> +	NFSD_A_SERVER_PROTO_MAX =3D (__NFSD_A_SERVER_PROTO_MAX - 1)
> +};
> +
>  enum {
>  	NFSD_CMD_RPC_STATUS_GET =3D 1,
>  	NFSD_CMD_THREADS_SET,
>  	NFSD_CMD_THREADS_GET,
> +	NFSD_CMD_VERSION_SET,
> +	NFSD_CMD_VERSION_GET,
> =20
>  	__NFSD_CMD_MAX,
>  	NFSD_CMD_MAX =3D (__NFSD_CMD_MAX - 1)
> diff --git a/tools/net/ynl/generated/nfsd-user.c b/tools/net/ynl/generate=
d/nfsd-user.c
> index f4121a52ccf8..ad498543f464 100644
> --- a/tools/net/ynl/generated/nfsd-user.c
> +++ b/tools/net/ynl/generated/nfsd-user.c
> @@ -17,6 +17,8 @@ static const char * const nfsd_op_strmap[] =3D {
>  	[NFSD_CMD_RPC_STATUS_GET] =3D "rpc-status-get",
>  	[NFSD_CMD_THREADS_SET] =3D "threads-set",
>  	[NFSD_CMD_THREADS_GET] =3D "threads-get",
> +	[NFSD_CMD_VERSION_SET] =3D "version-set",
> +	[NFSD_CMD_VERSION_GET] =3D "version-get",
>  };
> =20
>  const char *nfsd_op_str(int op)
> @@ -27,6 +29,16 @@ const char *nfsd_op_str(int op)
>  }
> =20
>  /* Policies */
> +struct ynl_policy_attr nfsd_nfs_version_policy[NFSD_A_NFS_VERSION_MAX + =
1] =3D {
> +	[NFSD_A_NFS_VERSION_MAJOR] =3D { .name =3D "major", .type =3D YNL_PT_U3=
2, },
> +	[NFSD_A_NFS_VERSION_MINOR] =3D { .name =3D "minor", .type =3D YNL_PT_U3=
2, },
> +};
> +
> +struct ynl_policy_nest nfsd_nfs_version_nest =3D {
> +	.max_attr =3D NFSD_A_NFS_VERSION_MAX,
> +	.table =3D nfsd_nfs_version_policy,
> +};
> +
>  struct ynl_policy_attr nfsd_rpc_status_policy[NFSD_A_RPC_STATUS_MAX + 1]=
 =3D {
>  	[NFSD_A_RPC_STATUS_XID] =3D { .name =3D "xid", .type =3D YNL_PT_U32, },
>  	[NFSD_A_RPC_STATUS_FLAGS] =3D { .name =3D "flags", .type =3D YNL_PT_U32=
, },
> @@ -58,7 +70,60 @@ struct ynl_policy_nest nfsd_server_worker_nest =3D {
>  	.table =3D nfsd_server_worker_policy,
>  };
> =20
> +struct ynl_policy_attr nfsd_server_proto_policy[NFSD_A_SERVER_PROTO_MAX =
+ 1] =3D {
> +	[NFSD_A_SERVER_PROTO_VERSION] =3D { .name =3D "version", .type =3D YNL_=
PT_NEST, .nest =3D &nfsd_nfs_version_nest, },
> +};
> +
> +struct ynl_policy_nest nfsd_server_proto_nest =3D {
> +	.max_attr =3D NFSD_A_SERVER_PROTO_MAX,
> +	.table =3D nfsd_server_proto_policy,
> +};
> +
>  /* Common nested types */
> +void nfsd_nfs_version_free(struct nfsd_nfs_version *obj)
> +{
> +}
> +
> +int nfsd_nfs_version_put(struct nlmsghdr *nlh, unsigned int attr_type,
> +			 struct nfsd_nfs_version *obj)
> +{
> +	struct nlattr *nest;
> +
> +	nest =3D mnl_attr_nest_start(nlh, attr_type);
> +	if (obj->_present.major)
> +		mnl_attr_put_u32(nlh, NFSD_A_NFS_VERSION_MAJOR, obj->major);
> +	if (obj->_present.minor)
> +		mnl_attr_put_u32(nlh, NFSD_A_NFS_VERSION_MINOR, obj->minor);
> +	mnl_attr_nest_end(nlh, nest);
> +
> +	return 0;
> +}
> +
> +int nfsd_nfs_version_parse(struct ynl_parse_arg *yarg,
> +			   const struct nlattr *nested)
> +{
> +	struct nfsd_nfs_version *dst =3D yarg->data;
> +	const struct nlattr *attr;
> +
> +	mnl_attr_for_each_nested(attr, nested) {
> +		unsigned int type =3D mnl_attr_get_type(attr);
> +
> +		if (type =3D=3D NFSD_A_NFS_VERSION_MAJOR) {
> +			if (ynl_attr_validate(yarg, attr))
> +				return MNL_CB_ERROR;
> +			dst->_present.major =3D 1;
> +			dst->major =3D mnl_attr_get_u32(attr);
> +		} else if (type =3D=3D NFSD_A_NFS_VERSION_MINOR) {
> +			if (ynl_attr_validate(yarg, attr))
> +				return MNL_CB_ERROR;
> +			dst->_present.minor =3D 1;
> +			dst->minor =3D mnl_attr_get_u32(attr);
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  /* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D NFSD_CMD_RPC_STATUS_GET =
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D */
>  /* NFSD_CMD_RPC_STATUS_GET - dump */
>  int nfsd_rpc_status_get_rsp_dump_parse(const struct nlmsghdr *nlh, void =
*data)
> @@ -291,6 +356,117 @@ struct nfsd_threads_get_rsp *nfsd_threads_get(struc=
t ynl_sock *ys)
>  	return NULL;
>  }
> =20
> +/* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D NFSD_CMD_VERSION_SET =3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D */
> +/* NFSD_CMD_VERSION_SET - do */
> +void nfsd_version_set_req_free(struct nfsd_version_set_req *req)
> +{
> +	unsigned int i;
> +
> +	for (i =3D 0; i < req->n_version; i++)
> +		nfsd_nfs_version_free(&req->version[i]);
> +	free(req->version);
> +	free(req);
> +}
> +
> +int nfsd_version_set(struct ynl_sock *ys, struct nfsd_version_set_req *r=
eq)
> +{
> +	struct ynl_req_state yrs =3D { .yarg =3D { .ys =3D ys, }, };
> +	struct nlmsghdr *nlh;
> +	int err;
> +
> +	nlh =3D ynl_gemsg_start_req(ys, ys->family_id, NFSD_CMD_VERSION_SET, 1)=
;
> +	ys->req_policy =3D &nfsd_server_proto_nest;
> +
> +	for (unsigned int i =3D 0; i < req->n_version; i++)
> +		nfsd_nfs_version_put(nlh, NFSD_A_SERVER_PROTO_VERSION, &req->version[i=
]);
> +
> +	err =3D ynl_exec(ys, nlh, &yrs);
> +	if (err < 0)
> +		return -1;
> +
> +	return 0;
> +}
> +
> +/* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D NFSD_CMD_VERSION_GET =3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D */
> +/* NFSD_CMD_VERSION_GET - do */
> +void nfsd_version_get_rsp_free(struct nfsd_version_get_rsp *rsp)
> +{
> +	unsigned int i;
> +
> +	for (i =3D 0; i < rsp->n_version; i++)
> +		nfsd_nfs_version_free(&rsp->version[i]);
> +	free(rsp->version);
> +	free(rsp);
> +}
> +
> +int nfsd_version_get_rsp_parse(const struct nlmsghdr *nlh, void *data)
> +{
> +	struct ynl_parse_arg *yarg =3D data;
> +	struct nfsd_version_get_rsp *dst;
> +	unsigned int n_version =3D 0;
> +	const struct nlattr *attr;
> +	struct ynl_parse_arg parg;
> +	int i;
> +
> +	dst =3D yarg->data;
> +	parg.ys =3D yarg->ys;
> +
> +	if (dst->version)
> +		return ynl_error_parse(yarg, "attribute already present (server-proto.=
version)");
> +
> +	mnl_attr_for_each(attr, nlh, sizeof(struct genlmsghdr)) {
> +		unsigned int type =3D mnl_attr_get_type(attr);
> +
> +		if (type =3D=3D NFSD_A_SERVER_PROTO_VERSION) {
> +			n_version++;
> +		}
> +	}
> +
> +	if (n_version) {
> +		dst->version =3D calloc(n_version, sizeof(*dst->version));
> +		dst->n_version =3D n_version;
> +		i =3D 0;
> +		parg.rsp_policy =3D &nfsd_nfs_version_nest;
> +		mnl_attr_for_each(attr, nlh, sizeof(struct genlmsghdr)) {
> +			if (mnl_attr_get_type(attr) =3D=3D NFSD_A_SERVER_PROTO_VERSION) {
> +				parg.data =3D &dst->version[i];
> +				if (nfsd_nfs_version_parse(&parg, attr))
> +					return MNL_CB_ERROR;
> +				i++;
> +			}
> +		}
> +	}
> +
> +	return MNL_CB_OK;
> +}
> +
> +struct nfsd_version_get_rsp *nfsd_version_get(struct ynl_sock *ys)
> +{
> +	struct ynl_req_state yrs =3D { .yarg =3D { .ys =3D ys, }, };
> +	struct nfsd_version_get_rsp *rsp;
> +	struct nlmsghdr *nlh;
> +	int err;
> +
> +	nlh =3D ynl_gemsg_start_req(ys, ys->family_id, NFSD_CMD_VERSION_GET, 1)=
;
> +	ys->req_policy =3D &nfsd_server_proto_nest;
> +	yrs.yarg.rsp_policy =3D &nfsd_server_proto_nest;
> +
> +	rsp =3D calloc(1, sizeof(*rsp));
> +	yrs.yarg.data =3D rsp;
> +	yrs.cb =3D nfsd_version_get_rsp_parse;
> +	yrs.rsp_cmd =3D NFSD_CMD_VERSION_GET;
> +
> +	err =3D ynl_exec(ys, nlh, &yrs);
> +	if (err < 0)
> +		goto err_free;
> +
> +	return rsp;
> +
> +err_free:
> +	nfsd_version_get_rsp_free(rsp);
> +	return NULL;
> +}
> +
>  const struct ynl_family ynl_nfsd_family =3D  {
>  	.name		=3D "nfsd",
>  };
> diff --git a/tools/net/ynl/generated/nfsd-user.h b/tools/net/ynl/generate=
d/nfsd-user.h
> index e162a4f20d91..d062ee8fa8b6 100644
> --- a/tools/net/ynl/generated/nfsd-user.h
> +++ b/tools/net/ynl/generated/nfsd-user.h
> @@ -19,6 +19,16 @@ extern const struct ynl_family ynl_nfsd_family;
>  const char *nfsd_op_str(int op);
> =20
>  /* Common nested types */
> +struct nfsd_nfs_version {
> +	struct {
> +		__u32 major:1;
> +		__u32 minor:1;
> +	} _present;
> +
> +	__u32 major;
> +	__u32 minor;
> +};
> +
>  /* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D NFSD_CMD_RPC_STATUS_GET =
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D */
>  /* NFSD_CMD_RPC_STATUS_GET - dump */
>  struct nfsd_rpc_status_get_rsp_dump {
> @@ -111,4 +121,47 @@ void nfsd_threads_get_rsp_free(struct nfsd_threads_g=
et_rsp *rsp);
>   */
>  struct nfsd_threads_get_rsp *nfsd_threads_get(struct ynl_sock *ys);
> =20
> +/* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D NFSD_CMD_VERSION_SET =3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D */
> +/* NFSD_CMD_VERSION_SET - do */
> +struct nfsd_version_set_req {
> +	unsigned int n_version;
> +	struct nfsd_nfs_version *version;
> +};
> +
> +static inline struct nfsd_version_set_req *nfsd_version_set_req_alloc(vo=
id)
> +{
> +	return calloc(1, sizeof(struct nfsd_version_set_req));
> +}
> +void nfsd_version_set_req_free(struct nfsd_version_set_req *req);
> +
> +static inline void
> +__nfsd_version_set_req_set_version(struct nfsd_version_set_req *req,
> +				   struct nfsd_nfs_version *version,
> +				   unsigned int n_version)
> +{
> +	free(req->version);
> +	req->version =3D version;
> +	req->n_version =3D n_version;
> +}
> +
> +/*
> + * set nfs enabled versions
> + */
> +int nfsd_version_set(struct ynl_sock *ys, struct nfsd_version_set_req *r=
eq);
> +
> +/* =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D NFSD_CMD_VERSION_GET =3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D */
> +/* NFSD_CMD_VERSION_GET - do */
> +
> +struct nfsd_version_get_rsp {
> +	unsigned int n_version;
> +	struct nfsd_nfs_version *version;
> +};
> +
> +void nfsd_version_get_rsp_free(struct nfsd_version_get_rsp *rsp);
> +
> +/*
> + * get nfs enabled versions
> + */
> +struct nfsd_version_get_rsp *nfsd_version_get(struct ynl_sock *ys);
> +
>  #endif /* _LINUX_NFSD_GEN_H */

--=20
Jeff Layton <jlayton@kernel.org>