1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2007 Red Hat, Inc. All rights reserved.
4 */
5
6 #include <net/genetlink.h>
7 #include <linux/dlm.h>
8 #include <linux/dlm_netlink.h>
9 #include <linux/gfp.h>
10
11 #include "dlm_internal.h"
12
13 static uint32_t dlm_nl_seqnum;
14 static uint32_t listener_nlportid;
15
16 static struct genl_family family;
17
prepare_data(u8 cmd,struct sk_buff ** skbp,size_t size)18 static int prepare_data(u8 cmd, struct sk_buff **skbp, size_t size)
19 {
20 struct sk_buff *skb;
21 void *data;
22
23 skb = genlmsg_new(size, GFP_NOFS);
24 if (!skb)
25 return -ENOMEM;
26
27 /* add the message headers */
28 data = genlmsg_put(skb, 0, dlm_nl_seqnum++, &family, 0, cmd);
29 if (!data) {
30 nlmsg_free(skb);
31 return -EINVAL;
32 }
33
34 *skbp = skb;
35 return 0;
36 }
37
mk_data(struct sk_buff * skb)38 static struct dlm_lock_data *mk_data(struct sk_buff *skb)
39 {
40 struct nlattr *ret;
41
42 ret = nla_reserve(skb, DLM_TYPE_LOCK, sizeof(struct dlm_lock_data));
43 if (!ret)
44 return NULL;
45 return nla_data(ret);
46 }
47
send_data(struct sk_buff * skb)48 static int send_data(struct sk_buff *skb)
49 {
50 struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data);
51 void *data = genlmsg_data(genlhdr);
52
53 genlmsg_end(skb, data);
54
55 return genlmsg_unicast(&init_net, skb, listener_nlportid);
56 }
57
user_cmd(struct sk_buff * skb,struct genl_info * info)58 static int user_cmd(struct sk_buff *skb, struct genl_info *info)
59 {
60 listener_nlportid = info->snd_portid;
61 printk("user_cmd nlpid %u\n", listener_nlportid);
62 return 0;
63 }
64
65 static const struct genl_small_ops dlm_nl_ops[] = {
66 {
67 .cmd = DLM_CMD_HELLO,
68 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
69 .doit = user_cmd,
70 },
71 };
72
73 static struct genl_family family __ro_after_init = {
74 .name = DLM_GENL_NAME,
75 .version = DLM_GENL_VERSION,
76 .small_ops = dlm_nl_ops,
77 .n_small_ops = ARRAY_SIZE(dlm_nl_ops),
78 .resv_start_op = DLM_CMD_HELLO + 1,
79 .module = THIS_MODULE,
80 };
81
dlm_netlink_init(void)82 int __init dlm_netlink_init(void)
83 {
84 return genl_register_family(&family);
85 }
86
dlm_netlink_exit(void)87 void dlm_netlink_exit(void)
88 {
89 genl_unregister_family(&family);
90 }
91
fill_data(struct dlm_lock_data * data,struct dlm_lkb * lkb)92 static void fill_data(struct dlm_lock_data *data, struct dlm_lkb *lkb)
93 {
94 struct dlm_rsb *r = lkb->lkb_resource;
95
96 memset(data, 0, sizeof(struct dlm_lock_data));
97
98 data->version = DLM_LOCK_DATA_VERSION;
99 data->nodeid = lkb->lkb_nodeid;
100 data->ownpid = lkb->lkb_ownpid;
101 data->id = lkb->lkb_id;
102 data->remid = lkb->lkb_remid;
103 data->status = lkb->lkb_status;
104 data->grmode = lkb->lkb_grmode;
105 data->rqmode = lkb->lkb_rqmode;
106 if (lkb->lkb_ua)
107 data->xid = lkb->lkb_ua->xid;
108 if (r) {
109 data->lockspace_id = r->res_ls->ls_global_id;
110 data->resource_namelen = r->res_length;
111 memcpy(data->resource_name, r->res_name, r->res_length);
112 }
113 }
114
dlm_timeout_warn(struct dlm_lkb * lkb)115 void dlm_timeout_warn(struct dlm_lkb *lkb)
116 {
117 struct sk_buff *send_skb;
118 struct dlm_lock_data *data;
119 size_t size;
120 int rv;
121
122 size = nla_total_size(sizeof(struct dlm_lock_data)) +
123 nla_total_size(0); /* why this? */
124
125 rv = prepare_data(DLM_CMD_TIMEOUT, &send_skb, size);
126 if (rv < 0)
127 return;
128
129 data = mk_data(send_skb);
130 if (!data) {
131 nlmsg_free(send_skb);
132 return;
133 }
134
135 fill_data(data, lkb);
136
137 send_data(send_skb);
138 }
139
140