summaryrefslogtreecommitdiff
path: root/fs/dlm/netlink.c
blob: 46e582c8d6032091df798102b1b17e69e3e993d1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
/*
 * Copyright (C) 2007 Red Hat, Inc.  All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License v.2.
 */

#include <net/genetlink.h>
#include <linux/dlm.h>
#include <linux/dlm_netlink.h>

#include "dlm_internal.h"

static uint32_t dlm_nl_seqnum;
static uint32_t listener_nlpid;

static struct genl_family family = {
	.id		= GENL_ID_GENERATE,
	.name		= DLM_GENL_NAME,
	.version	= DLM_GENL_VERSION,
};

static int prepare_data(u8 cmd, struct sk_buff **skbp, size_t size)
{
	struct sk_buff *skb;
	void *data;

	skb = genlmsg_new(size, GFP_KERNEL);
	if (!skb)
		return -ENOMEM;

	/* add the message headers */
	data = genlmsg_put(skb, 0, dlm_nl_seqnum++, &family, 0, cmd);
	if (!data) {
		nlmsg_free(skb);
		return -EINVAL;
	}

	*skbp = skb;
	return 0;
}

static struct dlm_lock_data *mk_data(struct sk_buff *skb)
{
	struct nlattr *ret;

	ret = nla_reserve(skb, DLM_TYPE_LOCK, sizeof(struct dlm_lock_data));
	if (!ret)
		return NULL;
	return nla_data(ret);
}

static int send_data(struct sk_buff *skb)
{
	struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data);
	void *data = genlmsg_data(genlhdr);
	int rv;

	rv = genlmsg_end(skb, data);
	if (rv < 0) {
		nlmsg_free(skb);
		return rv;
	}

	return genlmsg_unicast(skb, listener_nlpid);
}

static int user_cmd(struct sk_buff *skb, struct genl_info *info)
{
	listener_nlpid = info->snd_pid;
	printk("user_cmd nlpid %u\n", listener_nlpid);
	return 0;
}

static struct genl_ops dlm_nl_ops = {
	.cmd		= DLM_CMD_HELLO,
	.doit		= user_cmd,
};

int __init dlm_netlink_init(void)
{
	int rv;

	rv = genl_register_family(&family);
	if (rv)
		return rv;

	rv = genl_register_ops(&family, &dlm_nl_ops);
	if (rv < 0)
		goto err;
	return 0;
 err:
	genl_unregister_family(&family);
	return rv;
}

void dlm_netlink_exit(void)
{
	genl_unregister_ops(&family, &dlm_nl_ops);
	genl_unregister_family(&family);
}

static void fill_data(struct dlm_lock_data *data, struct dlm_lkb *lkb)
{
	struct dlm_rsb *r = lkb->lkb_resource;

	memset(data, 0, sizeof(struct dlm_lock_data));

	data->version = DLM_LOCK_DATA_VERSION;
	data->nodeid = lkb->lkb_nodeid;
	data->ownpid = lkb->lkb_ownpid;
	data->id = lkb->lkb_id;
	data->remid = lkb->lkb_remid;
	data->status = lkb->lkb_status;
	data->grmode = lkb->lkb_grmode;
	data->rqmode = lkb->lkb_rqmode;
	if (lkb->lkb_ua)
		data->xid = lkb->lkb_ua->xid;
	if (r) {
		data->lockspace_id = r->res_ls->ls_global_id;
		data->resource_namelen = r->res_length;
		memcpy(data->resource_name, r->res_name, r->res_length);
	}
}

void dlm_timeout_warn(struct dlm_lkb *lkb)
{
	struct dlm_lock_data *data;
	struct sk_buff *send_skb;
	size_t size;
	int rv;

	size = nla_total_size(sizeof(struct dlm_lock_data)) +
	       nla_total_size(0); /* why this? */

	rv = prepare_data(DLM_CMD_TIMEOUT, &send_skb, size);
	if (rv < 0)
		return;

	data = mk_data(send_skb);
	if (!data) {
		nlmsg_free(send_skb);
		return;
	}

	fill_data(data, lkb);

	send_data(send_skb);
}