1 /*
2  * Copyright (C) 2007 Red Hat, Inc.  All rights reserved.
3  *
4  * This copyrighted material is made available to anyone wishing to use,
5  * modify, copy, or redistribute it subject to the terms and conditions
6  * of the GNU General Public License v.2.
7  */
8 
9 #include <net/genetlink.h>
10 #include <linux/dlm.h>
11 #include <linux/dlm_netlink.h>
12 #include <linux/gfp.h>
13 
14 #include "dlm_internal.h"
15 
16 static uint32_t dlm_nl_seqnum;
17 static uint32_t listener_nlportid;
18 
19 static struct genl_family family;
20 
prepare_data(u8 cmd,struct sk_buff ** skbp,size_t size)21 static int prepare_data(u8 cmd, struct sk_buff **skbp, size_t size)
22 {
23 	struct sk_buff *skb;
24 	void *data;
25 
26 	skb = genlmsg_new(size, GFP_NOFS);
27 	if (!skb)
28 		return -ENOMEM;
29 
30 	/* add the message headers */
31 	data = genlmsg_put(skb, 0, dlm_nl_seqnum++, &family, 0, cmd);
32 	if (!data) {
33 		nlmsg_free(skb);
34 		return -EINVAL;
35 	}
36 
37 	*skbp = skb;
38 	return 0;
39 }
40 
mk_data(struct sk_buff * skb)41 static struct dlm_lock_data *mk_data(struct sk_buff *skb)
42 {
43 	struct nlattr *ret;
44 
45 	ret = nla_reserve(skb, DLM_TYPE_LOCK, sizeof(struct dlm_lock_data));
46 	if (!ret)
47 		return NULL;
48 	return nla_data(ret);
49 }
50 
send_data(struct sk_buff * skb)51 static int send_data(struct sk_buff *skb)
52 {
53 	struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data);
54 	void *data = genlmsg_data(genlhdr);
55 
56 	genlmsg_end(skb, data);
57 
58 	return genlmsg_unicast(&init_net, skb, listener_nlportid);
59 }
60 
user_cmd(struct sk_buff * skb,struct genl_info * info)61 static int user_cmd(struct sk_buff *skb, struct genl_info *info)
62 {
63 	listener_nlportid = info->snd_portid;
64 	printk("user_cmd nlpid %u\n", listener_nlportid);
65 	return 0;
66 }
67 
68 static const struct genl_ops dlm_nl_ops[] = {
69 	{
70 		.cmd	= DLM_CMD_HELLO,
71 		.doit	= user_cmd,
72 	},
73 };
74 
75 static struct genl_family family __ro_after_init = {
76 	.name		= DLM_GENL_NAME,
77 	.version	= DLM_GENL_VERSION,
78 	.ops		= dlm_nl_ops,
79 	.n_ops		= ARRAY_SIZE(dlm_nl_ops),
80 	.module		= THIS_MODULE,
81 };
82 
dlm_netlink_init(void)83 int __init dlm_netlink_init(void)
84 {
85 	return genl_register_family(&family);
86 }
87 
dlm_netlink_exit(void)88 void dlm_netlink_exit(void)
89 {
90 	genl_unregister_family(&family);
91 }
92 
fill_data(struct dlm_lock_data * data,struct dlm_lkb * lkb)93 static void fill_data(struct dlm_lock_data *data, struct dlm_lkb *lkb)
94 {
95 	struct dlm_rsb *r = lkb->lkb_resource;
96 
97 	memset(data, 0, sizeof(struct dlm_lock_data));
98 
99 	data->version = DLM_LOCK_DATA_VERSION;
100 	data->nodeid = lkb->lkb_nodeid;
101 	data->ownpid = lkb->lkb_ownpid;
102 	data->id = lkb->lkb_id;
103 	data->remid = lkb->lkb_remid;
104 	data->status = lkb->lkb_status;
105 	data->grmode = lkb->lkb_grmode;
106 	data->rqmode = lkb->lkb_rqmode;
107 	if (lkb->lkb_ua)
108 		data->xid = lkb->lkb_ua->xid;
109 	if (r) {
110 		data->lockspace_id = r->res_ls->ls_global_id;
111 		data->resource_namelen = r->res_length;
112 		memcpy(data->resource_name, r->res_name, r->res_length);
113 	}
114 }
115 
dlm_timeout_warn(struct dlm_lkb * lkb)116 void dlm_timeout_warn(struct dlm_lkb *lkb)
117 {
118 	struct sk_buff *send_skb;
119 	struct dlm_lock_data *data;
120 	size_t size;
121 	int rv;
122 
123 	size = nla_total_size(sizeof(struct dlm_lock_data)) +
124 	       nla_total_size(0); /* why this? */
125 
126 	rv = prepare_data(DLM_CMD_TIMEOUT, &send_skb, size);
127 	if (rv < 0)
128 		return;
129 
130 	data = mk_data(send_skb);
131 	if (!data) {
132 		nlmsg_free(send_skb);
133 		return;
134 	}
135 
136 	fill_data(data, lkb);
137 
138 	send_data(send_skb);
139 }
140 
141