summaryrefslogtreecommitdiff
path: root/source4/cluster/ctdb/ctdb_cluster.c
blob: 6bac35080521dde3ccfe503973d36fc4d540f357 (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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
/* 
   Unix SMB/CIFS implementation.

   ctdb clustering hooks

   Copyright (C) Andrew Tridgell 2006
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "lib/events/events.h"
#include "cluster/cluster.h"
#include "system/filesys.h"
#include "cluster/cluster_private.h"
#include "lib/tdb/include/tdb.h"
#include "include/ctdb.h"
#include "tdb_wrap.h"
#include "lib/util/dlinklist.h"
#include "param/param.h"
#include "librpc/gen_ndr/misc.h"

/* a linked list of messaging handlers, allowing incoming messages
   to be directed to the right messaging context */
struct cluster_messaging_list {
	struct cluster_messaging_list *next, *prev;
	struct cluster_state *state;
	struct messaging_context *msg;
	struct server_id server;
	cluster_message_fn_t handler;
};

struct cluster_state {
	struct ctdb_context *ctdb;
	struct cluster_messaging_list *list;
	uint32_t vnn;
};



/*
  return a server_id for a ctdb node
*/
static struct server_id ctdb_id(struct cluster_ops *ops, uint32_t id)
{
	struct cluster_state *state = (struct cluster_state *)ops->private;
	struct ctdb_context *ctdb = state->ctdb;
	struct server_id server_id;
	server_id.node = ctdb_get_vnn(ctdb);
	server_id.id = id;
	return server_id;
}


/*
  return a server_id as a string
*/
static const char *ctdb_id_string(struct cluster_ops *ops, 
				  TALLOC_CTX *mem_ctx, struct server_id id)
{
	return talloc_asprintf(mem_ctx, "%u.%u", id.node, id.id);
}

/*
  this is an interim method for subsystems that have not yet been
  converted to use the ctdb api. It opens a shared database in the
  cluster temporary area, using TDB_CLEAR_IF_FIRST which relies on
  correct operation of fcntl locks on the shared fileystem.
*/
static struct tdb_wrap *ctdb_tdb_tmp_open(struct cluster_ops *ops,
					  TALLOC_CTX *mem_ctx, 
					  const char *dbname, int flags)
{
	const char *dir = lp_parm_string(global_loadparm, NULL, "ctdb", "shared data");
	char *path;
	struct tdb_wrap *w;
	if (dir == NULL) {
		DEBUG(0,("ERROR: You must set 'ctdb:shared data' to a cluster shared path\n"));
		return NULL;
	}
	path = talloc_asprintf(mem_ctx, "%s/%s", dir, dbname);
	w = tdb_wrap_open(mem_ctx, path, 0,  
			  flags | TDB_CLEAR_IF_FIRST,
			  O_RDWR|O_CREAT, 0600);
	talloc_free(path);
	return w;
}

/*
  get at the ctdb handle
*/
static void *ctdb_backend_handle(struct cluster_ops *ops)
{
	struct cluster_state *state = (struct cluster_state *)ops->private;
	return (void *)state->ctdb;
}

struct ctdb_handler_state {
	struct cluster_state *state;
	cluster_message_fn_t handler;
	struct messaging_context *msg;
};

/*
  dispatch incoming ctdb messages
*/
static void ctdb_message_handler(struct ctdb_context *ctdb, uint64_t srvid, 
				 TDB_DATA data, void *private)
{
	struct ctdb_handler_state *s = talloc_get_type(private, 
						       struct ctdb_handler_state);
	DATA_BLOB blob;
	blob.data = data.dptr;
	blob.length = data.dsize;
	s->handler(s->msg, blob);
}

static int ctdb_handler_destructor(struct ctdb_handler_state *s)
{
	/* XXX - tell ctdb to de-register the message handler */
	return 0;
}

/*
  setup a handler for ctdb messages
*/
static NTSTATUS ctdb_message_init(struct cluster_ops *ops,
				  struct messaging_context *msg, 
				  struct server_id server,
				  cluster_message_fn_t handler)
{
	struct cluster_state *state = (struct cluster_state *)ops->private;
	struct ctdb_handler_state *h;
	int ret;

	h = talloc(msg, struct ctdb_handler_state);
	NT_STATUS_HAVE_NO_MEMORY(h);

	h->state = state;
	h->handler = handler;
	h->msg = msg;

	talloc_set_destructor(h, ctdb_handler_destructor);

	/* setup a message handler */
	ret = ctdb_set_message_handler(state->ctdb, server.id, 
				       ctdb_message_handler, h);
        if (ret == -1) {
                DEBUG(0,("ctdb_set_message_handler failed - %s\n", 
			 ctdb_errstr(state->ctdb)));
		exit(1);
        }

	return NT_STATUS_OK;
}

/*
  send a ctdb message to another node
*/
static NTSTATUS ctdb_message_send(struct cluster_ops *ops,
				  struct server_id server, DATA_BLOB *data)
{
	struct cluster_state *state = (struct cluster_state *)ops->private;
	struct ctdb_context *ctdb = state->ctdb;
	TDB_DATA tdata;
	int ret;

	tdata.dptr = data->data;
	tdata.dsize = data->length;

	ret = ctdb_send_message(ctdb, server.node, server.id, tdata);
	if (ret != 0) {
		return NT_STATUS_INTERNAL_DB_CORRUPTION;
	}
	return NT_STATUS_OK;
}

static struct cluster_ops cluster_ctdb_ops = {
	.cluster_id           = ctdb_id,
	.cluster_id_string    = ctdb_id_string,
	.cluster_tdb_tmp_open = ctdb_tdb_tmp_open,
	.backend_handle       = ctdb_backend_handle,
	.message_init         = ctdb_message_init,
	.message_send         = ctdb_message_send,
	.private           = NULL
};

/* initialise ctdb */
void cluster_ctdb_init(struct loadparm_context *lp_ctx, 
		       struct event_context *ev, const char *model)
{
	struct cluster_state *state;
	int ret;

	if (!lp_parm_bool(lp_ctx, NULL, "ctdb", "enable", false)) {
		return;
	}

	state = talloc(ev, struct cluster_state);
	if (state == NULL) goto failed;

	state->ctdb = ctdb_init(ev);
	if (state->ctdb == NULL) goto failed;

	ret = ctdb_socket_connect(state->ctdb);
	if (ret == -1) {
		DEBUG(0,(__location__ " Failed to connect to ctdb socket\n"));
		goto failed;
	}

	/* get our vnn */
	state->vnn = ctdb_ctrl_getvnn(state->ctdb, timeval_zero(), CTDB_CURRENT_NODE);
	if (state->vnn == (uint32_t)-1) {
		DEBUG(0,(__location__ " Failed to get ctdb vnn\n"));
		goto failed;
	}

	state->list = NULL;

	cluster_ctdb_ops.private = state;

	cluster_set_ops(&cluster_ctdb_ops);

#if 0
	/* nasty hack for now ... */
	{
		void brl_ctdb_init_ops(void);
		brl_ctdb_init_ops();
	}
#endif

	return;
	
failed:
	DEBUG(0,("cluster_ctdb_init failed\n"));
	talloc_free(state);
}