[PATCH v5 2/3] NFSD: convert write_version to netlink command

Lorenzo Bianconi
2023-11-29T17:13:16Z

Introduce write_version netlink command similar to the ones available
through the procfs.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
Documentation/netlink/specs/nfsd.yaml | 32 ++++++++
fs/nfsd/netlink.c | 19 +++++
fs/nfsd/netlink.h | 3 +
fs/nfsd/nfsctl.c | 105 ++++++++++++++++++++++++++
include/uapi/linux/nfsd_netlink.h | 11 +++
tools/net/ynl/generated/nfsd-user.c | 81 ++++++++++++++++++++
tools/net/ynl/generated/nfsd-user.h | 55 ++++++++++++++
7 files changed, 306 insertions(+)

diff --git a/Documentation/netlink/specs/nfsd.yaml b/Documentation/netlink/specs/nfsd.yaml
index c92e1425d316..6c5e42bb20f6 100644
--- a/Documentation/netlink/specs/nfsd.yaml
+++ b/Documentation/netlink/specs/nfsd.yaml
@@ -68,6 +68,18 @@ attribute-sets:
-
name: threads
type: u32
+ -
+ name: server-version
+ attributes:
+ -
+ name: major
+ type: u32
+ -
+ name: minor
+ type: u32
+ -
+ name: status
+ type: u8

operations:
list:
@@ -110,3 +122,23 @@ operations:
reply:
attributes:
- threads
+ -
+ name: version-set
+ doc: enable/disable server version
+ attribute-set: server-version
+ flags: [ admin-perm ]
+ do:
+ request:
+ attributes:
+ - major
+ - minor
+ - status
+ -
+ name: version-get
+ doc: dump server versions
+ attribute-set: server-version
+ dump:
+ reply:
+ attributes:
+ - major
+ - minor
diff --git a/fs/nfsd/netlink.c b/fs/nfsd/netlink.c
index 1a59a8e6c7e2..0608a7bd193b 100644
--- a/fs/nfsd/netlink.c
+++ b/fs/nfsd/netlink.c
@@ -15,6 +15,13 @@ static const struct nla_policy nfsd_threads_set_nl_policy[NFSD_A_SERVER_WORKER_T
[NFSD_A_SERVER_WORKER_THREADS] = { .type = NLA_U32, },
};

+/* NFSD_CMD_VERSION_SET - do */
+static const struct nla_policy nfsd_version_set_nl_policy[NFSD_A_SERVER_VERSION_STATUS + 1] = {
+ [NFSD_A_SERVER_VERSION_MAJOR] = { .type = NLA_U32, },
+ [NFSD_A_SERVER_VERSION_MINOR] = { .type = NLA_U32, },
+ [NFSD_A_SERVER_VERSION_STATUS] = { .type = NLA_U8, },
+};
+
/* Ops table for nfsd */
static const struct genl_split_ops nfsd_nl_ops[] = {
{
@@ -36,6 +43,18 @@ static const struct genl_split_ops nfsd_nl_ops[] = {
.doit = nfsd_nl_threads_get_doit,
.flags = GENL_CMD_CAP_DO,
},
+ {
+ .cmd = NFSD_CMD_VERSION_SET,
+ .doit = nfsd_nl_version_set_doit,
+ .policy = nfsd_version_set_nl_policy,
+ .maxattr = NFSD_A_SERVER_VERSION_STATUS,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = NFSD_CMD_VERSION_GET,
+ .dumpit = nfsd_nl_version_get_dumpit,
+ .flags = GENL_CMD_CAP_DUMP,
+ },
};

struct genl_family nfsd_nl_family __ro_after_init = {
diff --git a/fs/nfsd/netlink.h b/fs/nfsd/netlink.h
index 4137fac477e4..7d203cec08e4 100644
--- a/fs/nfsd/netlink.h
+++ b/fs/nfsd/netlink.h
@@ -18,6 +18,9 @@ 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_dumpit(struct sk_buff *skb,
+ struct netlink_callback *cb);

extern struct genl_family nfsd_nl_family;

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 130b3d937a79..f04430f79687 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -1757,6 +1757,111 @@ int nfsd_nl_threads_get_doit(struct sk_buff *skb, struct genl_info *info)
return err;
}

+/**
+ * nfsd_nl_version_set_doit - enable/disable the provided nfs server version
+ * @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)
+{
+ struct nfsd_net *nn = net_generic(genl_info_net(info), nfsd_net_id);
+ enum vers_op cmd;
+ u32 major, minor;
+ u8 status;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, NFSD_A_SERVER_VERSION_MAJOR) ||
+ GENL_REQ_ATTR_CHECK(info, NFSD_A_SERVER_VERSION_MINOR) ||
+ GENL_REQ_ATTR_CHECK(info, NFSD_A_SERVER_VERSION_STATUS))
+ return -EINVAL;
+
+ major = nla_get_u32(info->attrs[NFSD_A_SERVER_VERSION_MAJOR]);
+ minor = nla_get_u32(info->attrs[NFSD_A_SERVER_VERSION_MINOR]);
+
+ status = nla_get_u32(info->attrs[NFSD_A_SERVER_VERSION_STATUS]);
+ cmd = !!status ? NFSD_SET : NFSD_CLEAR;
+
+ mutex_lock(&nfsd_mutex);
+ switch (major) {
+ case 4:
+ ret = nfsd_minorversion(nn, minor, cmd);
+ break;
+ case 2:
+ case 3:
+ if (!minor) {
+ ret = nfsd_vers(nn, major, cmd);
+ break;
+ }
+ fallthrough;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ mutex_unlock(&nfsd_mutex);
+
+ return ret;
+}
+
+/**
+ * nfsd_nl_version_get_doit - Handle verion_get dumpit
+ * @skb: reply buffer
+ * @cb: netlink metadata and command arguments
+ *
+ * Returns the size of the reply or a negative errno.
+ */
+int nfsd_nl_version_get_dumpit(struct sk_buff *skb,
+ struct netlink_callback *cb)
+{
+ struct nfsd_net *nn = net_generic(sock_net(skb->sk), nfsd_net_id);
+ int i, ret = -ENOMEM;
+
+ mutex_lock(&nfsd_mutex);
+
+ for (i = 2; i <= 4; i++) {
+ int j;
+
+ if (i < cb->args[0]) /* already consumed */
+ continue;
+
+ if (!nfsd_vers(nn, i, NFSD_AVAIL))
+ continue;
+
+ for (j = 0; j <= NFSD_SUPPORTED_MINOR_VERSION; j++) {
+ void *hdr;
+
+ if (!nfsd_vers(nn, i, NFSD_TEST))
+ continue;
+
+ /* NFSv{2,3} does not support minor numbers */
+ if (i < 4 && j)
+ continue;
+
+ if (i == 4 && !nfsd_minorversion(nn, j, NFSD_TEST))
+ continue;
+
+ hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, &nfsd_nl_family,
+ 0, NFSD_CMD_VERSION_GET);
+ if (!hdr)
+ goto out;
+
+ if (nla_put_u32(skb, NFSD_A_SERVER_VERSION_MAJOR, i) ||
+ nla_put_u32(skb, NFSD_A_SERVER_VERSION_MINOR, j))
+ goto out;
+
+ genlmsg_end(skb, hdr);
+ }
+ }
+ cb->args[0] = i;
+ ret = skb->len;
+out:
+ mutex_unlock(&nfsd_mutex);
+
+ return ret;
+}
+
/**
* 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..1b3340f31baa 100644
--- a/include/uapi/linux/nfsd_netlink.h
+++ b/include/uapi/linux/nfsd_netlink.h
@@ -36,10 +36,21 @@ enum {
NFSD_A_SERVER_WORKER_MAX = (__NFSD_A_SERVER_WORKER_MAX - 1)
};

+enum {
+ NFSD_A_SERVER_VERSION_MAJOR = 1,
+ NFSD_A_SERVER_VERSION_MINOR,
+ NFSD_A_SERVER_VERSION_STATUS,
+
+ __NFSD_A_SERVER_VERSION_MAX,
+ NFSD_A_SERVER_VERSION_MAX = (__NFSD_A_SERVER_VERSION_MAX - 1)
+};
+
enum {
NFSD_CMD_RPC_STATUS_GET = 1,
NFSD_CMD_THREADS_SET,
NFSD_CMD_THREADS_GET,
+ NFSD_CMD_VERSION_SET,
+ NFSD_CMD_VERSION_GET,

__NFSD_CMD_MAX,
NFSD_CMD_MAX = (__NFSD_CMD_MAX - 1)
diff --git a/tools/net/ynl/generated/nfsd-user.c b/tools/net/ynl/generated/nfsd-user.c
index 9768328a7751..4cb71c3cd18d 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[] = {
[NFSD_CMD_RPC_STATUS_GET] = "rpc-status-get",
[NFSD_CMD_THREADS_SET] = "threads-set",
[NFSD_CMD_THREADS_GET] = "threads-get",
+ [NFSD_CMD_VERSION_SET] = "version-set",
+ [NFSD_CMD_VERSION_GET] = "version-get",
};

const char *nfsd_op_str(int op)
@@ -58,6 +60,17 @@ struct ynl_policy_nest nfsd_server_worker_nest = {
.table = nfsd_server_worker_policy,
};

+struct ynl_policy_attr nfsd_server_version_policy[NFSD_A_SERVER_VERSION_MAX + 1] = {
+ [NFSD_A_SERVER_VERSION_MAJOR] = { .name = "major", .type = YNL_PT_U32, },
+ [NFSD_A_SERVER_VERSION_MINOR] = { .name = "minor", .type = YNL_PT_U32, },
+ [NFSD_A_SERVER_VERSION_STATUS] = { .name = "status", .type = YNL_PT_U8, },
+};
+
+struct ynl_policy_nest nfsd_server_version_nest = {
+ .max_attr = NFSD_A_SERVER_VERSION_MAX,
+ .table = nfsd_server_version_policy,
+};
+
/* Common nested types */
/* ============== NFSD_CMD_RPC_STATUS_GET ============== */
/* NFSD_CMD_RPC_STATUS_GET - dump */
@@ -290,6 +303,74 @@ struct nfsd_threads_get_rsp *nfsd_threads_get(struct ynl_sock *ys)
return NULL;
}

+/* ============== NFSD_CMD_VERSION_SET ============== */
+/* NFSD_CMD_VERSION_SET - do */
+void nfsd_version_set_req_free(struct nfsd_version_set_req *req)
+{
+ free(req);
+}
+
+int nfsd_version_set(struct ynl_sock *ys, struct nfsd_version_set_req *req)
+{
+ struct nlmsghdr *nlh;
+ int err;
+
+ nlh = ynl_gemsg_start_req(ys, ys->family_id, NFSD_CMD_VERSION_SET, 1);
+ ys->req_policy = &nfsd_server_version_nest;
+
+ if (req->_present.major)
+ mnl_attr_put_u32(nlh, NFSD_A_SERVER_VERSION_MAJOR, req->major);
+ if (req->_present.minor)
+ mnl_attr_put_u32(nlh, NFSD_A_SERVER_VERSION_MINOR, req->minor);
+ if (req->_present.status)
+ mnl_attr_put_u8(nlh, NFSD_A_SERVER_VERSION_STATUS, req->status);
+
+ err = ynl_exec(ys, nlh, NULL);
+ if (err < 0)
+ return -1;
+
+ return 0;
+}
+
+/* ============== NFSD_CMD_VERSION_GET ============== */
+/* NFSD_CMD_VERSION_GET - dump */
+void nfsd_version_get_list_free(struct nfsd_version_get_list *rsp)
+{
+ struct nfsd_version_get_list *next = rsp;
+
+ while ((void *)next != YNL_LIST_END) {
+ rsp = next;
+ next = rsp->next;
+
+ free(rsp);
+ }
+}
+
+struct nfsd_version_get_list *nfsd_version_get_dump(struct ynl_sock *ys)
+{
+ struct ynl_dump_state yds = {};
+ struct nlmsghdr *nlh;
+ int err;
+
+ yds.ys = ys;
+ yds.alloc_sz = sizeof(struct nfsd_version_get_list);
+ yds.cb = nfsd_version_get_rsp_parse;
+ yds.rsp_cmd = NFSD_CMD_VERSION_GET;
+ yds.rsp_policy = &nfsd_server_version_nest;
+
+ nlh = ynl_gemsg_start_dump(ys, ys->family_id, NFSD_CMD_VERSION_GET, 1);
+
+ err = ynl_exec_dump(ys, nlh, &yds);
+ if (err < 0)
+ goto free_list;
+
+ return yds.first;
+
+free_list:
+ nfsd_version_get_list_free(yds.first);
+ return NULL;
+}
+
const struct ynl_family ynl_nfsd_family = {
.name = "nfsd",
};
diff --git a/tools/net/ynl/generated/nfsd-user.h b/tools/net/ynl/generated/nfsd-user.h
index e162a4f20d91..e61c5a9e46fb 100644
--- a/tools/net/ynl/generated/nfsd-user.h
+++ b/tools/net/ynl/generated/nfsd-user.h
@@ -111,4 +111,59 @@ void nfsd_threads_get_rsp_free(struct nfsd_threads_get_rsp *rsp);
*/
struct nfsd_threads_get_rsp *nfsd_threads_get(struct ynl_sock *ys);

+/* ============== NFSD_CMD_VERSION_SET ============== */
+/* NFSD_CMD_VERSION_SET - do */
+struct nfsd_version_set_req {
+ struct {
+ __u32 major:1;
+ __u32 minor:1;
+ __u32 status:1;
+ } _present;
+
+ __u32 major;
+ __u32 minor;
+ __u8 status;
+};
+
+static inline struct nfsd_version_set_req *nfsd_version_set_req_alloc(void)
+{
+ 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_major(struct nfsd_version_set_req *req, __u32 major)
+{
+ req->_present.major = 1;
+ req->major = major;
+}
+static inline void
+nfsd_version_set_req_set_minor(struct nfsd_version_set_req *req, __u32 minor)
+{
+ req->_present.minor = 1;
+ req->minor = minor;
+}
+static inline void
+nfsd_version_set_req_set_status(struct nfsd_version_set_req *req, __u8 status)
+{
+ req->_present.status = 1;
+ req->status = status;
+}
+
+/*
+ * enable/disable server version
+ */
+int nfsd_version_set(struct ynl_sock *ys, struct nfsd_version_set_req *req);
+
+/* ============== NFSD_CMD_VERSION_GET ============== */
+/* NFSD_CMD_VERSION_GET - dump */
+struct nfsd_version_get_list {
+ struct nfsd_version_get_list *next;
+ struct nfsd_version_get_rsp obj __attribute__ ((aligned (8)));
+};
+
+void nfsd_version_get_list_free(struct nfsd_version_get_list *rsp);
+
+struct nfsd_version_get_list *nfsd_version_get_dump(struct ynl_sock *ys);
+
#endif /* _LINUX_NFSD_GEN_H */
--
2.43.0