xref: /linux/fs/ocfs2/heartbeat.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * heartbeat.c
5  *
6  * Register ourselves with the heartbaet service, keep our node maps
7  * up to date, and fire off recovery when needed.
8  *
9  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public
13  * License as published by the Free Software Foundation; either
14  * version 2 of the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  * General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public
22  * License along with this program; if not, write to the
23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24  * Boston, MA 021110-1307, USA.
25  */
26 
27 #include <linux/fs.h>
28 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/highmem.h>
31 #include <linux/kmod.h>
32 
33 #include <cluster/heartbeat.h>
34 #include <cluster/nodemanager.h>
35 
36 #include <dlm/dlmapi.h>
37 
38 #define MLOG_MASK_PREFIX ML_SUPER
39 #include <cluster/masklog.h>
40 
41 #include "ocfs2.h"
42 
43 #include "alloc.h"
44 #include "heartbeat.h"
45 #include "inode.h"
46 #include "journal.h"
47 #include "vote.h"
48 
49 #include "buffer_head_io.h"
50 
51 #define OCFS2_HB_NODE_DOWN_PRI     (0x0000002)
52 #define OCFS2_HB_NODE_UP_PRI	   OCFS2_HB_NODE_DOWN_PRI
53 
54 static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
55 					    int bit);
56 static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
57 					      int bit);
58 static inline int __ocfs2_node_map_is_empty(struct ocfs2_node_map *map);
59 static void __ocfs2_node_map_dup(struct ocfs2_node_map *target,
60 				 struct ocfs2_node_map *from);
61 static void __ocfs2_node_map_set(struct ocfs2_node_map *target,
62 				 struct ocfs2_node_map *from);
63 
64 void ocfs2_init_node_maps(struct ocfs2_super *osb)
65 {
66 	spin_lock_init(&osb->node_map_lock);
67 	ocfs2_node_map_init(&osb->mounted_map);
68 	ocfs2_node_map_init(&osb->recovery_map);
69 	ocfs2_node_map_init(&osb->umount_map);
70 	ocfs2_node_map_init(&osb->osb_recovering_orphan_dirs);
71 }
72 
73 static void ocfs2_do_node_down(int node_num,
74 			       struct ocfs2_super *osb)
75 {
76 	BUG_ON(osb->node_num == node_num);
77 
78 	mlog(0, "ocfs2: node down event for %d\n", node_num);
79 
80 	if (!osb->dlm) {
81 		/*
82 		 * No DLM means we're not even ready to participate yet.
83 		 * We check the slots after the DLM comes up, so we will
84 		 * notice the node death then.  We can safely ignore it
85 		 * here.
86 		 */
87 		return;
88 	}
89 
90 	if (ocfs2_node_map_test_bit(osb, &osb->umount_map, node_num)) {
91 		/* If a node is in the umount map, then we've been
92 		 * expecting him to go down and we know ahead of time
93 		 * that recovery is not necessary. */
94 		ocfs2_node_map_clear_bit(osb, &osb->umount_map, node_num);
95 		return;
96 	}
97 
98 	ocfs2_recovery_thread(osb, node_num);
99 
100 	ocfs2_remove_node_from_vote_queues(osb, node_num);
101 }
102 
103 static void ocfs2_hb_node_down_cb(struct o2nm_node *node,
104 				  int node_num,
105 				  void *data)
106 {
107 	ocfs2_do_node_down(node_num, (struct ocfs2_super *) data);
108 }
109 
110 /* Called from the dlm when it's about to evict a node. We may also
111  * get a heartbeat callback later. */
112 static void ocfs2_dlm_eviction_cb(int node_num,
113 				  void *data)
114 {
115 	struct ocfs2_super *osb = (struct ocfs2_super *) data;
116 	struct super_block *sb = osb->sb;
117 
118 	mlog(ML_NOTICE, "device (%u,%u): dlm has evicted node %d\n",
119 	     MAJOR(sb->s_dev), MINOR(sb->s_dev), node_num);
120 
121 	ocfs2_do_node_down(node_num, osb);
122 }
123 
124 static void ocfs2_hb_node_up_cb(struct o2nm_node *node,
125 				int node_num,
126 				void *data)
127 {
128 	struct ocfs2_super *osb = data;
129 
130 	BUG_ON(osb->node_num == node_num);
131 
132 	mlog(0, "node up event for %d\n", node_num);
133 	ocfs2_node_map_clear_bit(osb, &osb->umount_map, node_num);
134 }
135 
136 void ocfs2_setup_hb_callbacks(struct ocfs2_super *osb)
137 {
138 	o2hb_setup_callback(&osb->osb_hb_down, O2HB_NODE_DOWN_CB,
139 			    ocfs2_hb_node_down_cb, osb,
140 			    OCFS2_HB_NODE_DOWN_PRI);
141 
142 	o2hb_setup_callback(&osb->osb_hb_up, O2HB_NODE_UP_CB,
143 			    ocfs2_hb_node_up_cb, osb, OCFS2_HB_NODE_UP_PRI);
144 
145 	/* Not exactly a heartbeat callback, but leads to essentially
146 	 * the same path so we set it up here. */
147 	dlm_setup_eviction_cb(&osb->osb_eviction_cb,
148 			      ocfs2_dlm_eviction_cb,
149 			      osb);
150 }
151 
152 /* Most functions here are just stubs for now... */
153 int ocfs2_register_hb_callbacks(struct ocfs2_super *osb)
154 {
155 	int status;
156 
157 	status = o2hb_register_callback(&osb->osb_hb_down);
158 	if (status < 0) {
159 		mlog_errno(status);
160 		goto bail;
161 	}
162 
163 	status = o2hb_register_callback(&osb->osb_hb_up);
164 	if (status < 0)
165 		mlog_errno(status);
166 
167 bail:
168 	return status;
169 }
170 
171 void ocfs2_clear_hb_callbacks(struct ocfs2_super *osb)
172 {
173 	int status;
174 
175 	status = o2hb_unregister_callback(&osb->osb_hb_down);
176 	if (status < 0)
177 		mlog_errno(status);
178 
179 	status = o2hb_unregister_callback(&osb->osb_hb_up);
180 	if (status < 0)
181 		mlog_errno(status);
182 }
183 
184 void ocfs2_stop_heartbeat(struct ocfs2_super *osb)
185 {
186 	int ret;
187 	char *argv[5], *envp[3];
188 
189 	if (!osb->uuid_str) {
190 		/* This can happen if we don't get far enough in mount... */
191 		mlog(0, "No UUID with which to stop heartbeat!\n\n");
192 		return;
193 	}
194 
195 	argv[0] = (char *)o2nm_get_hb_ctl_path();
196 	argv[1] = "-K";
197 	argv[2] = "-u";
198 	argv[3] = osb->uuid_str;
199 	argv[4] = NULL;
200 
201 	mlog(0, "Run: %s %s %s %s\n", argv[0], argv[1], argv[2], argv[3]);
202 
203 	/* minimal command environment taken from cpu_run_sbin_hotplug */
204 	envp[0] = "HOME=/";
205 	envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
206 	envp[2] = NULL;
207 
208 	ret = call_usermodehelper(argv[0], argv, envp, 1);
209 	if (ret < 0)
210 		mlog_errno(ret);
211 }
212 
213 /* special case -1 for now
214  * TODO: should *really* make sure the calling func never passes -1!!  */
215 void ocfs2_node_map_init(struct ocfs2_node_map *map)
216 {
217 	map->num_nodes = OCFS2_NODE_MAP_MAX_NODES;
218 	memset(map->map, 0, BITS_TO_LONGS(OCFS2_NODE_MAP_MAX_NODES) *
219 	       sizeof(unsigned long));
220 }
221 
222 static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
223 					    int bit)
224 {
225 	set_bit(bit, map->map);
226 }
227 
228 void ocfs2_node_map_set_bit(struct ocfs2_super *osb,
229 			    struct ocfs2_node_map *map,
230 			    int bit)
231 {
232 	if (bit==-1)
233 		return;
234 	BUG_ON(bit >= map->num_nodes);
235 	spin_lock(&osb->node_map_lock);
236 	__ocfs2_node_map_set_bit(map, bit);
237 	spin_unlock(&osb->node_map_lock);
238 }
239 
240 static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
241 					      int bit)
242 {
243 	clear_bit(bit, map->map);
244 }
245 
246 void ocfs2_node_map_clear_bit(struct ocfs2_super *osb,
247 			      struct ocfs2_node_map *map,
248 			      int bit)
249 {
250 	if (bit==-1)
251 		return;
252 	BUG_ON(bit >= map->num_nodes);
253 	spin_lock(&osb->node_map_lock);
254 	__ocfs2_node_map_clear_bit(map, bit);
255 	spin_unlock(&osb->node_map_lock);
256 }
257 
258 int ocfs2_node_map_test_bit(struct ocfs2_super *osb,
259 			    struct ocfs2_node_map *map,
260 			    int bit)
261 {
262 	int ret;
263 	if (bit >= map->num_nodes) {
264 		mlog(ML_ERROR, "bit=%d map->num_nodes=%d\n", bit, map->num_nodes);
265 		BUG();
266 	}
267 	spin_lock(&osb->node_map_lock);
268 	ret = test_bit(bit, map->map);
269 	spin_unlock(&osb->node_map_lock);
270 	return ret;
271 }
272 
273 static inline int __ocfs2_node_map_is_empty(struct ocfs2_node_map *map)
274 {
275 	int bit;
276 	bit = find_next_bit(map->map, map->num_nodes, 0);
277 	if (bit < map->num_nodes)
278 		return 0;
279 	return 1;
280 }
281 
282 int ocfs2_node_map_is_empty(struct ocfs2_super *osb,
283 			    struct ocfs2_node_map *map)
284 {
285 	int ret;
286 	BUG_ON(map->num_nodes == 0);
287 	spin_lock(&osb->node_map_lock);
288 	ret = __ocfs2_node_map_is_empty(map);
289 	spin_unlock(&osb->node_map_lock);
290 	return ret;
291 }
292 
293 static void __ocfs2_node_map_dup(struct ocfs2_node_map *target,
294 				 struct ocfs2_node_map *from)
295 {
296 	BUG_ON(from->num_nodes == 0);
297 	ocfs2_node_map_init(target);
298 	__ocfs2_node_map_set(target, from);
299 }
300 
301 /* returns 1 if bit is the only bit set in target, 0 otherwise */
302 int ocfs2_node_map_is_only(struct ocfs2_super *osb,
303 			   struct ocfs2_node_map *target,
304 			   int bit)
305 {
306 	struct ocfs2_node_map temp;
307 	int ret;
308 
309 	spin_lock(&osb->node_map_lock);
310 	__ocfs2_node_map_dup(&temp, target);
311 	__ocfs2_node_map_clear_bit(&temp, bit);
312 	ret = __ocfs2_node_map_is_empty(&temp);
313 	spin_unlock(&osb->node_map_lock);
314 
315 	return ret;
316 }
317 
318 static void __ocfs2_node_map_set(struct ocfs2_node_map *target,
319 				 struct ocfs2_node_map *from)
320 {
321 	int num_longs, i;
322 
323 	BUG_ON(target->num_nodes != from->num_nodes);
324 	BUG_ON(target->num_nodes == 0);
325 
326 	num_longs = BITS_TO_LONGS(target->num_nodes);
327 	for (i = 0; i < num_longs; i++)
328 		target->map[i] = from->map[i];
329 }
330 
331 /* Returns whether the recovery bit was actually set - it may not be
332  * if a node is still marked as needing recovery */
333 int ocfs2_recovery_map_set(struct ocfs2_super *osb,
334 			   int num)
335 {
336 	int set = 0;
337 
338 	spin_lock(&osb->node_map_lock);
339 
340 	__ocfs2_node_map_clear_bit(&osb->mounted_map, num);
341 
342 	if (!test_bit(num, osb->recovery_map.map)) {
343 	    __ocfs2_node_map_set_bit(&osb->recovery_map, num);
344 	    set = 1;
345 	}
346 
347 	spin_unlock(&osb->node_map_lock);
348 
349 	return set;
350 }
351 
352 void ocfs2_recovery_map_clear(struct ocfs2_super *osb,
353 			      int num)
354 {
355 	ocfs2_node_map_clear_bit(osb, &osb->recovery_map, num);
356 }
357 
358 int ocfs2_node_map_iterate(struct ocfs2_super *osb,
359 			   struct ocfs2_node_map *map,
360 			   int idx)
361 {
362 	int i = idx;
363 
364 	idx = O2NM_INVALID_NODE_NUM;
365 	spin_lock(&osb->node_map_lock);
366 	if ((i != O2NM_INVALID_NODE_NUM) &&
367 	    (i >= 0) &&
368 	    (i < map->num_nodes)) {
369 		while(i < map->num_nodes) {
370 			if (test_bit(i, map->map)) {
371 				idx = i;
372 				break;
373 			}
374 			i++;
375 		}
376 	}
377 	spin_unlock(&osb->node_map_lock);
378 	return idx;
379 }
380