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Merge tag 'v3.3.7' into 3.3/master
[zen-stable.git] / fs / ocfs2 / cluster / heartbeat.c
bloba4e855e3690e6ab844d37788b71649975321cb19
1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * Copyright (C) 2004, 2005 Oracle. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public
17 * License along with this program; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 021110-1307, USA.
20 */
21
22 #include <linux/kernel.h>
23 #include <linux/sched.h>
24 #include <linux/jiffies.h>
25 #include <linux/module.h>
26 #include <linux/fs.h>
27 #include <linux/bio.h>
28 #include <linux/blkdev.h>
29 #include <linux/delay.h>
30 #include <linux/file.h>
31 #include <linux/kthread.h>
32 #include <linux/configfs.h>
33 #include <linux/random.h>
34 #include <linux/crc32.h>
35 #include <linux/time.h>
36 #include <linux/debugfs.h>
37 #include <linux/slab.h>
38
39 #include "heartbeat.h"
40 #include "tcp.h"
41 #include "nodemanager.h"
42 #include "quorum.h"
43
44 #include "masklog.h"
45
46
47 /*
48 * The first heartbeat pass had one global thread that would serialize all hb
49 * callback calls. This global serializing sem should only be removed once
50 * we've made sure that all callees can deal with being called concurrently
51 * from multiple hb region threads.
52 */
53 static DECLARE_RWSEM(o2hb_callback_sem);
54
55 /*
56 * multiple hb threads are watching multiple regions. A node is live
57 * whenever any of the threads sees activity from the node in its region.
58 */
59 static DEFINE_SPINLOCK(o2hb_live_lock);
60 static struct list_head o2hb_live_slots[O2NM_MAX_NODES];
61 static unsigned long o2hb_live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
62 static LIST_HEAD(o2hb_node_events);
63 static DECLARE_WAIT_QUEUE_HEAD(o2hb_steady_queue);
64
65 /*
66 * In global heartbeat, we maintain a series of region bitmaps.
67 * - o2hb_region_bitmap allows us to limit the region number to max region.
68 * - o2hb_live_region_bitmap tracks live regions (seen steady iterations).
69 * - o2hb_quorum_region_bitmap tracks live regions that have seen all nodes
70 * heartbeat on it.
71 * - o2hb_failed_region_bitmap tracks the regions that have seen io timeouts.
72 */
73 static unsigned long o2hb_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
74 static unsigned long o2hb_live_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
75 static unsigned long o2hb_quorum_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
76 static unsigned long o2hb_failed_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
77
78 #define O2HB_DB_TYPE_LIVENODES 0
79 #define O2HB_DB_TYPE_LIVEREGIONS 1
80 #define O2HB_DB_TYPE_QUORUMREGIONS 2
81 #define O2HB_DB_TYPE_FAILEDREGIONS 3
82 #define O2HB_DB_TYPE_REGION_LIVENODES 4
83 #define O2HB_DB_TYPE_REGION_NUMBER 5
84 #define O2HB_DB_TYPE_REGION_ELAPSED_TIME 6
85 #define O2HB_DB_TYPE_REGION_PINNED 7
86 struct o2hb_debug_buf {
87 int db_type;
88 int db_size;
89 int db_len;
90 void *db_data;
91 };
92
93 static struct o2hb_debug_buf *o2hb_db_livenodes;
94 static struct o2hb_debug_buf *o2hb_db_liveregions;
95 static struct o2hb_debug_buf *o2hb_db_quorumregions;
96 static struct o2hb_debug_buf *o2hb_db_failedregions;
97
98 #define O2HB_DEBUG_DIR "o2hb"
99 #define O2HB_DEBUG_LIVENODES "livenodes"
100 #define O2HB_DEBUG_LIVEREGIONS "live_regions"
101 #define O2HB_DEBUG_QUORUMREGIONS "quorum_regions"
102 #define O2HB_DEBUG_FAILEDREGIONS "failed_regions"
103 #define O2HB_DEBUG_REGION_NUMBER "num"
104 #define O2HB_DEBUG_REGION_ELAPSED_TIME "elapsed_time_in_ms"
105 #define O2HB_DEBUG_REGION_PINNED "pinned"
106
107 static struct dentry *o2hb_debug_dir;
108 static struct dentry *o2hb_debug_livenodes;
109 static struct dentry *o2hb_debug_liveregions;
110 static struct dentry *o2hb_debug_quorumregions;
111 static struct dentry *o2hb_debug_failedregions;
112
113 static LIST_HEAD(o2hb_all_regions);
114
115 static struct o2hb_callback {
116 struct list_head list;
117 } o2hb_callbacks[O2HB_NUM_CB];
118
119 static struct o2hb_callback *hbcall_from_type(enum o2hb_callback_type type);
120
121 #define O2HB_DEFAULT_BLOCK_BITS 9
122
123 enum o2hb_heartbeat_modes {
124 O2HB_HEARTBEAT_LOCAL = 0,
125 O2HB_HEARTBEAT_GLOBAL,
126 O2HB_HEARTBEAT_NUM_MODES,
127 };
128
129 char *o2hb_heartbeat_mode_desc[O2HB_HEARTBEAT_NUM_MODES] = {
130 "local", /* O2HB_HEARTBEAT_LOCAL */
131 "global", /* O2HB_HEARTBEAT_GLOBAL */
132 };
133
134 unsigned int o2hb_dead_threshold = O2HB_DEFAULT_DEAD_THRESHOLD;
135 unsigned int o2hb_heartbeat_mode = O2HB_HEARTBEAT_LOCAL;
136
137 /*
138 * o2hb_dependent_users tracks the number of registered callbacks that depend
139 * on heartbeat. o2net and o2dlm are two entities that register this callback.
140 * However only o2dlm depends on the heartbeat. It does not want the heartbeat
141 * to stop while a dlm domain is still active.
142 */
143 unsigned int o2hb_dependent_users;
144
145 /*
146 * In global heartbeat mode, all regions are pinned if there are one or more
147 * dependent users and the quorum region count is <= O2HB_PIN_CUT_OFF. All
148 * regions are unpinned if the region count exceeds the cut off or the number
149 * of dependent users falls to zero.
150 */
151 #define O2HB_PIN_CUT_OFF 3
152
153 /*
154 * In local heartbeat mode, we assume the dlm domain name to be the same as
155 * region uuid. This is true for domains created for the file system but not
156 * necessarily true for userdlm domains. This is a known limitation.
157 *
158 * In global heartbeat mode, we pin/unpin all o2hb regions. This solution
159 * works for both file system and userdlm domains.
160 */
161 static int o2hb_region_pin(const char *region_uuid);
162 static void o2hb_region_unpin(const char *region_uuid);
163
164 /* Only sets a new threshold if there are no active regions.
165 *
166 * No locking or otherwise interesting code is required for reading
167 * o2hb_dead_threshold as it can't change once regions are active and
168 * it's not interesting to anyone until then anyway. */
169 static void o2hb_dead_threshold_set(unsigned int threshold)
170 {
171 if (threshold > O2HB_MIN_DEAD_THRESHOLD) {
172 spin_lock(&o2hb_live_lock);
173 if (list_empty(&o2hb_all_regions))
174 o2hb_dead_threshold = threshold;
175 spin_unlock(&o2hb_live_lock);
176 }
177 }
178
179 static int o2hb_global_hearbeat_mode_set(unsigned int hb_mode)
180 {
181 int ret = -1;
182
183 if (hb_mode < O2HB_HEARTBEAT_NUM_MODES) {
184 spin_lock(&o2hb_live_lock);
185 if (list_empty(&o2hb_all_regions)) {
186 o2hb_heartbeat_mode = hb_mode;
187 ret = 0;
188 }
189 spin_unlock(&o2hb_live_lock);
190 }
191
192 return ret;
193 }
194
195 struct o2hb_node_event {
196 struct list_head hn_item;
197 enum o2hb_callback_type hn_event_type;
198 struct o2nm_node *hn_node;
199 int hn_node_num;
200 };
201
202 struct o2hb_disk_slot {
203 struct o2hb_disk_heartbeat_block *ds_raw_block;
204 u8 ds_node_num;
205 u64 ds_last_time;
206 u64 ds_last_generation;
207 u16 ds_equal_samples;
208 u16 ds_changed_samples;
209 struct list_head ds_live_item;
210 };
211
212 /* each thread owns a region.. when we're asked to tear down the region
213 * we ask the thread to stop, who cleans up the region */
214 struct o2hb_region {
215 struct config_item hr_item;
216
217 struct list_head hr_all_item;
218 unsigned hr_unclean_stop:1,
219 hr_aborted_start:1,
220 hr_item_pinned:1,
221 hr_item_dropped:1;
222
223 /* protected by the hr_callback_sem */
224 struct task_struct *hr_task;
225
226 unsigned int hr_blocks;
227 unsigned long long hr_start_block;
228
229 unsigned int hr_block_bits;
230 unsigned int hr_block_bytes;
231
232 unsigned int hr_slots_per_page;
233 unsigned int hr_num_pages;
234
235 struct page **hr_slot_data;
236 struct block_device *hr_bdev;
237 struct o2hb_disk_slot *hr_slots;
238
239 /* live node map of this region */
240 unsigned long hr_live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
241 unsigned int hr_region_num;
242
243 struct dentry *hr_debug_dir;
244 struct dentry *hr_debug_livenodes;
245 struct dentry *hr_debug_regnum;
246 struct dentry *hr_debug_elapsed_time;
247 struct dentry *hr_debug_pinned;
248 struct o2hb_debug_buf *hr_db_livenodes;
249 struct o2hb_debug_buf *hr_db_regnum;
250 struct o2hb_debug_buf *hr_db_elapsed_time;
251 struct o2hb_debug_buf *hr_db_pinned;
252
253 /* let the person setting up hb wait for it to return until it
254 * has reached a 'steady' state. This will be fixed when we have
255 * a more complete api that doesn't lead to this sort of fragility. */
256 atomic_t hr_steady_iterations;
257
258 /* terminate o2hb thread if it does not reach steady state
259 * (hr_steady_iterations == 0) within hr_unsteady_iterations */
260 atomic_t hr_unsteady_iterations;
261
262 char hr_dev_name[BDEVNAME_SIZE];
263
264 unsigned int hr_timeout_ms;
265
266 /* randomized as the region goes up and down so that a node
267 * recognizes a node going up and down in one iteration */
268 u64 hr_generation;
269
270 struct delayed_work hr_write_timeout_work;
271 unsigned long hr_last_timeout_start;
272
273 /* Used during o2hb_check_slot to hold a copy of the block
274 * being checked because we temporarily have to zero out the
275 * crc field. */
276 struct o2hb_disk_heartbeat_block *hr_tmp_block;
277 };
278
279 struct o2hb_bio_wait_ctxt {
280 atomic_t wc_num_reqs;
281 struct completion wc_io_complete;
282 int wc_error;
283 };
284
285 static int o2hb_pop_count(void *map, int count)
286 {
287 int i = -1, pop = 0;
288
289 while ((i = find_next_bit(map, count, i + 1)) < count)
290 pop++;
291 return pop;
292 }
293
294 static void o2hb_write_timeout(struct work_struct *work)
295 {
296 int failed, quorum;
297 unsigned long flags;
298 struct o2hb_region *reg =
299 container_of(work, struct o2hb_region,
300 hr_write_timeout_work.work);
301
302 mlog(ML_ERROR, "Heartbeat write timeout to device %s after %u "
303 "milliseconds\n", reg->hr_dev_name,
304 jiffies_to_msecs(jiffies - reg->hr_last_timeout_start));
305
306 if (o2hb_global_heartbeat_active()) {
307 spin_lock_irqsave(&o2hb_live_lock, flags);
308 if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
309 set_bit(reg->hr_region_num, o2hb_failed_region_bitmap);
310 failed = o2hb_pop_count(&o2hb_failed_region_bitmap,
311 O2NM_MAX_REGIONS);
312 quorum = o2hb_pop_count(&o2hb_quorum_region_bitmap,
313 O2NM_MAX_REGIONS);
314 spin_unlock_irqrestore(&o2hb_live_lock, flags);
315
316 mlog(ML_HEARTBEAT, "Number of regions %d, failed regions %d\n",
317 quorum, failed);
318
319 /*
320 * Fence if the number of failed regions >= half the number
321 * of quorum regions
322 */
323 if ((failed << 1) < quorum)
324 return;
325 }
326
327 o2quo_disk_timeout();
328 }
329
330 static void o2hb_arm_write_timeout(struct o2hb_region *reg)
331 {
332 /* Arm writeout only after thread reaches steady state */
333 if (atomic_read(&reg->hr_steady_iterations) != 0)
334 return;
335
336 mlog(ML_HEARTBEAT, "Queue write timeout for %u ms\n",
337 O2HB_MAX_WRITE_TIMEOUT_MS);
338
339 if (o2hb_global_heartbeat_active()) {
340 spin_lock(&o2hb_live_lock);
341 clear_bit(reg->hr_region_num, o2hb_failed_region_bitmap);
342 spin_unlock(&o2hb_live_lock);
343 }
344 cancel_delayed_work(&reg->hr_write_timeout_work);
345 reg->hr_last_timeout_start = jiffies;
346 schedule_delayed_work(&reg->hr_write_timeout_work,
347 msecs_to_jiffies(O2HB_MAX_WRITE_TIMEOUT_MS));
348 }
349
350 static void o2hb_disarm_write_timeout(struct o2hb_region *reg)
351 {
352 cancel_delayed_work_sync(&reg->hr_write_timeout_work);
353 }
354
355 static inline void o2hb_bio_wait_init(struct o2hb_bio_wait_ctxt *wc)
356 {
357 atomic_set(&wc->wc_num_reqs, 1);
358 init_completion(&wc->wc_io_complete);
359 wc->wc_error = 0;
360 }
361
362 /* Used in error paths too */
363 static inline void o2hb_bio_wait_dec(struct o2hb_bio_wait_ctxt *wc,
364 unsigned int num)
365 {
366 /* sadly atomic_sub_and_test() isn't available on all platforms. The
367 * good news is that the fast path only completes one at a time */
368 while(num--) {
369 if (atomic_dec_and_test(&wc->wc_num_reqs)) {
370 BUG_ON(num > 0);
371 complete(&wc->wc_io_complete);
372 }
373 }
374 }
375
376 static void o2hb_wait_on_io(struct o2hb_region *reg,
377 struct o2hb_bio_wait_ctxt *wc)
378 {
379 o2hb_bio_wait_dec(wc, 1);
380 wait_for_completion(&wc->wc_io_complete);
381 }
382
383 static void o2hb_bio_end_io(struct bio *bio,
384 int error)
385 {
386 struct o2hb_bio_wait_ctxt *wc = bio->bi_private;
387
388 if (error) {
389 mlog(ML_ERROR, "IO Error %d\n", error);
390 wc->wc_error = error;
391 }
392
393 o2hb_bio_wait_dec(wc, 1);
394 bio_put(bio);
395 }
396
397 /* Setup a Bio to cover I/O against num_slots slots starting at
398 * start_slot. */
399 static struct bio *o2hb_setup_one_bio(struct o2hb_region *reg,
400 struct o2hb_bio_wait_ctxt *wc,
401 unsigned int *current_slot,
402 unsigned int max_slots)
403 {
404 int len, current_page;
405 unsigned int vec_len, vec_start;
406 unsigned int bits = reg->hr_block_bits;
407 unsigned int spp = reg->hr_slots_per_page;
408 unsigned int cs = *current_slot;
409 struct bio *bio;
410 struct page *page;
411
412 /* Testing has shown this allocation to take long enough under
413 * GFP_KERNEL that the local node can get fenced. It would be
414 * nicest if we could pre-allocate these bios and avoid this
415 * all together. */
416 bio = bio_alloc(GFP_ATOMIC, 16);
417 if (!bio) {
418 mlog(ML_ERROR, "Could not alloc slots BIO!\n");
419 bio = ERR_PTR(-ENOMEM);
420 goto bail;
421 }
422
423 /* Must put everything in 512 byte sectors for the bio... */
424 bio->bi_sector = (reg->hr_start_block + cs) << (bits - 9);
425 bio->bi_bdev = reg->hr_bdev;
426 bio->bi_private = wc;
427 bio->bi_end_io = o2hb_bio_end_io;
428
429 vec_start = (cs << bits) % PAGE_CACHE_SIZE;
430 while(cs < max_slots) {
431 current_page = cs / spp;
432 page = reg->hr_slot_data[current_page];
433
434 vec_len = min(PAGE_CACHE_SIZE - vec_start,
435 (max_slots-cs) * (PAGE_CACHE_SIZE/spp) );
436
437 mlog(ML_HB_BIO, "page %d, vec_len = %u, vec_start = %u\n",
438 current_page, vec_len, vec_start);
439
440 len = bio_add_page(bio, page, vec_len, vec_start);
441 if (len != vec_len) break;
442
443 cs += vec_len / (PAGE_CACHE_SIZE/spp);
444 vec_start = 0;
445 }
446
447 bail:
448 *current_slot = cs;
449 return bio;
450 }
451
452 static int o2hb_read_slots(struct o2hb_region *reg,
453 unsigned int max_slots)
454 {
455 unsigned int current_slot=0;
456 int status;
457 struct o2hb_bio_wait_ctxt wc;
458 struct bio *bio;
459
460 o2hb_bio_wait_init(&wc);
461
462 while(current_slot < max_slots) {
463 bio = o2hb_setup_one_bio(reg, &wc, &current_slot, max_slots);
464 if (IS_ERR(bio)) {
465 status = PTR_ERR(bio);
466 mlog_errno(status);
467 goto bail_and_wait;
468 }
469
470 atomic_inc(&wc.wc_num_reqs);
471 submit_bio(READ, bio);
472 }
473
474 status = 0;
475
476 bail_and_wait:
477 o2hb_wait_on_io(reg, &wc);
478 if (wc.wc_error && !status)
479 status = wc.wc_error;
480
481 return status;
482 }
483
484 static int o2hb_issue_node_write(struct o2hb_region *reg,
485 struct o2hb_bio_wait_ctxt *write_wc)
486 {
487 int status;
488 unsigned int slot;
489 struct bio *bio;
490
491 o2hb_bio_wait_init(write_wc);
492
493 slot = o2nm_this_node();
494
495 bio = o2hb_setup_one_bio(reg, write_wc, &slot, slot+1);
496 if (IS_ERR(bio)) {
497 status = PTR_ERR(bio);
498 mlog_errno(status);
499 goto bail;
500 }
501
502 atomic_inc(&write_wc->wc_num_reqs);
503 submit_bio(WRITE, bio);
504
505 status = 0;
506 bail:
507 return status;
508 }
509
510 static u32 o2hb_compute_block_crc_le(struct o2hb_region *reg,
511 struct o2hb_disk_heartbeat_block *hb_block)
512 {
513 __le32 old_cksum;
514 u32 ret;
515
516 /* We want to compute the block crc with a 0 value in the
517 * hb_cksum field. Save it off here and replace after the
518 * crc. */
519 old_cksum = hb_block->hb_cksum;
520 hb_block->hb_cksum = 0;
521
522 ret = crc32_le(0, (unsigned char *) hb_block, reg->hr_block_bytes);
523
524 hb_block->hb_cksum = old_cksum;
525
526 return ret;
527 }
528
529 static void o2hb_dump_slot(struct o2hb_disk_heartbeat_block *hb_block)
530 {
531 mlog(ML_ERROR, "Dump slot information: seq = 0x%llx, node = %u, "
532 "cksum = 0x%x, generation 0x%llx\n",
533 (long long)le64_to_cpu(hb_block->hb_seq),
534 hb_block->hb_node, le32_to_cpu(hb_block->hb_cksum),
535 (long long)le64_to_cpu(hb_block->hb_generation));
536 }
537
538 static int o2hb_verify_crc(struct o2hb_region *reg,
539 struct o2hb_disk_heartbeat_block *hb_block)
540 {
541 u32 read, computed;
542
543 read = le32_to_cpu(hb_block->hb_cksum);
544 computed = o2hb_compute_block_crc_le(reg, hb_block);
545
546 return read == computed;
547 }
548
549 /*
550 * Compare the slot data with what we wrote in the last iteration.
551 * If the match fails, print an appropriate error message. This is to
552 * detect errors like... another node hearting on the same slot,
553 * flaky device that is losing writes, etc.
554 * Returns 1 if check succeeds, 0 otherwise.
555 */
556 static int o2hb_check_own_slot(struct o2hb_region *reg)
557 {
558 struct o2hb_disk_slot *slot;
559 struct o2hb_disk_heartbeat_block *hb_block;
560 char *errstr;
561
562 slot = &reg->hr_slots[o2nm_this_node()];
563 /* Don't check on our 1st timestamp */
564 if (!slot->ds_last_time)
565 return 0;
566
567 hb_block = slot->ds_raw_block;
568 if (le64_to_cpu(hb_block->hb_seq) == slot->ds_last_time &&
569 le64_to_cpu(hb_block->hb_generation) == slot->ds_last_generation &&
570 hb_block->hb_node == slot->ds_node_num)
571 return 1;
572
573 #define ERRSTR1 "Another node is heartbeating on device"
574 #define ERRSTR2 "Heartbeat generation mismatch on device"
575 #define ERRSTR3 "Heartbeat sequence mismatch on device"
576
577 if (hb_block->hb_node != slot->ds_node_num)
578 errstr = ERRSTR1;
579 else if (le64_to_cpu(hb_block->hb_generation) !=
580 slot->ds_last_generation)
581 errstr = ERRSTR2;
582 else
583 errstr = ERRSTR3;
584
585 mlog(ML_ERROR, "%s (%s): expected(%u:0x%llx, 0x%llx), "
586 "ondisk(%u:0x%llx, 0x%llx)\n", errstr, reg->hr_dev_name,
587 slot->ds_node_num, (unsigned long long)slot->ds_last_generation,
588 (unsigned long long)slot->ds_last_time, hb_block->hb_node,
589 (unsigned long long)le64_to_cpu(hb_block->hb_generation),
590 (unsigned long long)le64_to_cpu(hb_block->hb_seq));
591
592 return 0;
593 }
594
595 static inline void o2hb_prepare_block(struct o2hb_region *reg,
596 u64 generation)
597 {
598 int node_num;
599 u64 cputime;
600 struct o2hb_disk_slot *slot;
601 struct o2hb_disk_heartbeat_block *hb_block;
602
603 node_num = o2nm_this_node();
604 slot = &reg->hr_slots[node_num];
605
606 hb_block = (struct o2hb_disk_heartbeat_block *)slot->ds_raw_block;
607 memset(hb_block, 0, reg->hr_block_bytes);
608 /* TODO: time stuff */
609 cputime = CURRENT_TIME.tv_sec;
610 if (!cputime)
611 cputime = 1;
612
613 hb_block->hb_seq = cpu_to_le64(cputime);
614 hb_block->hb_node = node_num;
615 hb_block->hb_generation = cpu_to_le64(generation);
616 hb_block->hb_dead_ms = cpu_to_le32(o2hb_dead_threshold * O2HB_REGION_TIMEOUT_MS);
617
618 /* This step must always happen last! */
619 hb_block->hb_cksum = cpu_to_le32(o2hb_compute_block_crc_le(reg,
620 hb_block));
621
622 mlog(ML_HB_BIO, "our node generation = 0x%llx, cksum = 0x%x\n",
623 (long long)generation,
624 le32_to_cpu(hb_block->hb_cksum));
625 }
626
627 static void o2hb_fire_callbacks(struct o2hb_callback *hbcall,
628 struct o2nm_node *node,
629 int idx)
630 {
631 struct list_head *iter;
632 struct o2hb_callback_func *f;
633
634 list_for_each(iter, &hbcall->list) {
635 f = list_entry(iter, struct o2hb_callback_func, hc_item);
636 mlog(ML_HEARTBEAT, "calling funcs %p\n", f);
637 (f->hc_func)(node, idx, f->hc_data);
638 }
639 }
640
641 /* Will run the list in order until we process the passed event */
642 static void o2hb_run_event_list(struct o2hb_node_event *queued_event)
643 {
644 int empty;
645 struct o2hb_callback *hbcall;
646 struct o2hb_node_event *event;
647
648 spin_lock(&o2hb_live_lock);
649 empty = list_empty(&queued_event->hn_item);
650 spin_unlock(&o2hb_live_lock);
651 if (empty)
652 return;
653
654 /* Holding callback sem assures we don't alter the callback
655 * lists when doing this, and serializes ourselves with other
656 * processes wanting callbacks. */
657 down_write(&o2hb_callback_sem);
658
659 spin_lock(&o2hb_live_lock);
660 while (!list_empty(&o2hb_node_events)
661 && !list_empty(&queued_event->hn_item)) {
662 event = list_entry(o2hb_node_events.next,
663 struct o2hb_node_event,
664 hn_item);
665 list_del_init(&event->hn_item);
666 spin_unlock(&o2hb_live_lock);
667
668 mlog(ML_HEARTBEAT, "Node %s event for %d\n",
669 event->hn_event_type == O2HB_NODE_UP_CB ? "UP" : "DOWN",
670 event->hn_node_num);
671
672 hbcall = hbcall_from_type(event->hn_event_type);
673
674 /* We should *never* have gotten on to the list with a
675 * bad type... This isn't something that we should try
676 * to recover from. */
677 BUG_ON(IS_ERR(hbcall));
678
679 o2hb_fire_callbacks(hbcall, event->hn_node, event->hn_node_num);
680
681 spin_lock(&o2hb_live_lock);
682 }
683 spin_unlock(&o2hb_live_lock);
684
685 up_write(&o2hb_callback_sem);
686 }
687
688 static void o2hb_queue_node_event(struct o2hb_node_event *event,
689 enum o2hb_callback_type type,
690 struct o2nm_node *node,
691 int node_num)
692 {
693 assert_spin_locked(&o2hb_live_lock);
694
695 BUG_ON((!node) && (type != O2HB_NODE_DOWN_CB));
696
697 event->hn_event_type = type;
698 event->hn_node = node;
699 event->hn_node_num = node_num;
700
701 mlog(ML_HEARTBEAT, "Queue node %s event for node %d\n",
702 type == O2HB_NODE_UP_CB ? "UP" : "DOWN", node_num);
703
704 list_add_tail(&event->hn_item, &o2hb_node_events);
705 }
706
707 static void o2hb_shutdown_slot(struct o2hb_disk_slot *slot)
708 {
709 struct o2hb_node_event event =
710 { .hn_item = LIST_HEAD_INIT(event.hn_item), };
711 struct o2nm_node *node;
712
713 node = o2nm_get_node_by_num(slot->ds_node_num);
714 if (!node)
715 return;
716
717 spin_lock(&o2hb_live_lock);
718 if (!list_empty(&slot->ds_live_item)) {
719 mlog(ML_HEARTBEAT, "Shutdown, node %d leaves region\n",
720 slot->ds_node_num);
721
722 list_del_init(&slot->ds_live_item);
723
724 if (list_empty(&o2hb_live_slots[slot->ds_node_num])) {
725 clear_bit(slot->ds_node_num, o2hb_live_node_bitmap);
726
727 o2hb_queue_node_event(&event, O2HB_NODE_DOWN_CB, node,
728 slot->ds_node_num);
729 }
730 }
731 spin_unlock(&o2hb_live_lock);
732
733 o2hb_run_event_list(&event);
734
735 o2nm_node_put(node);
736 }
737
738 static void o2hb_set_quorum_device(struct o2hb_region *reg)
739 {
740 if (!o2hb_global_heartbeat_active())
741 return;
742
743 /* Prevent race with o2hb_heartbeat_group_drop_item() */
744 if (kthread_should_stop())
745 return;
746
747 /* Tag region as quorum only after thread reaches steady state */
748 if (atomic_read(&reg->hr_steady_iterations) != 0)
749 return;
750
751 spin_lock(&o2hb_live_lock);
752
753 if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
754 goto unlock;
755
756 /*
757 * A region can be added to the quorum only when it sees all
758 * live nodes heartbeat on it. In other words, the region has been
759 * added to all nodes.
760 */
761 if (memcmp(reg->hr_live_node_bitmap, o2hb_live_node_bitmap,
762 sizeof(o2hb_live_node_bitmap)))
763 goto unlock;
764
765 printk(KERN_NOTICE "o2hb: Region %s (%s) is now a quorum device\n",
766 config_item_name(&reg->hr_item), reg->hr_dev_name);
767
768 set_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
769
770 /*
771 * If global heartbeat active, unpin all regions if the
772 * region count > CUT_OFF
773 */
774 if (o2hb_pop_count(&o2hb_quorum_region_bitmap,
775 O2NM_MAX_REGIONS) > O2HB_PIN_CUT_OFF)
776 o2hb_region_unpin(NULL);
777 unlock:
778 spin_unlock(&o2hb_live_lock);
779 }
780
781 static int o2hb_check_slot(struct o2hb_region *reg,
782 struct o2hb_disk_slot *slot)
783 {
784 int changed = 0, gen_changed = 0;
785 struct o2hb_node_event event =
786 { .hn_item = LIST_HEAD_INIT(event.hn_item), };
787 struct o2nm_node *node;
788 struct o2hb_disk_heartbeat_block *hb_block = reg->hr_tmp_block;
789 u64 cputime;
790 unsigned int dead_ms = o2hb_dead_threshold * O2HB_REGION_TIMEOUT_MS;
791 unsigned int slot_dead_ms;
792 int tmp;
793
794 memcpy(hb_block, slot->ds_raw_block, reg->hr_block_bytes);
795
796 /*
797 * If a node is no longer configured but is still in the livemap, we
798 * may need to clear that bit from the livemap.
799 */
800 node = o2nm_get_node_by_num(slot->ds_node_num);
801 if (!node) {
802 spin_lock(&o2hb_live_lock);
803 tmp = test_bit(slot->ds_node_num, o2hb_live_node_bitmap);
804 spin_unlock(&o2hb_live_lock);
805 if (!tmp)
806 return 0;
807 }
808
809 if (!o2hb_verify_crc(reg, hb_block)) {
810 /* all paths from here will drop o2hb_live_lock for
811 * us. */
812 spin_lock(&o2hb_live_lock);
813
814 /* Don't print an error on the console in this case -
815 * a freshly formatted heartbeat area will not have a
816 * crc set on it. */
817 if (list_empty(&slot->ds_live_item))
818 goto out;
819
820 /* The node is live but pushed out a bad crc. We
821 * consider it a transient miss but don't populate any
822 * other values as they may be junk. */
823 mlog(ML_ERROR, "Node %d has written a bad crc to %s\n",
824 slot->ds_node_num, reg->hr_dev_name);
825 o2hb_dump_slot(hb_block);
826
827 slot->ds_equal_samples++;
828 goto fire_callbacks;
829 }
830
831 /* we don't care if these wrap.. the state transitions below
832 * clear at the right places */
833 cputime = le64_to_cpu(hb_block->hb_seq);
834 if (slot->ds_last_time != cputime)
835 slot->ds_changed_samples++;
836 else
837 slot->ds_equal_samples++;
838 slot->ds_last_time = cputime;
839
840 /* The node changed heartbeat generations. We assume this to
841 * mean it dropped off but came back before we timed out. We
842 * want to consider it down for the time being but don't want
843 * to lose any changed_samples state we might build up to
844 * considering it live again. */
845 if (slot->ds_last_generation != le64_to_cpu(hb_block->hb_generation)) {
846 gen_changed = 1;
847 slot->ds_equal_samples = 0;
848 mlog(ML_HEARTBEAT, "Node %d changed generation (0x%llx "
849 "to 0x%llx)\n", slot->ds_node_num,
850 (long long)slot->ds_last_generation,
851 (long long)le64_to_cpu(hb_block->hb_generation));
852 }
853
854 slot->ds_last_generation = le64_to_cpu(hb_block->hb_generation);
855
856 mlog(ML_HEARTBEAT, "Slot %d gen 0x%llx cksum 0x%x "
857 "seq %llu last %llu changed %u equal %u\n",
858 slot->ds_node_num, (long long)slot->ds_last_generation,
859 le32_to_cpu(hb_block->hb_cksum),
860 (unsigned long long)le64_to_cpu(hb_block->hb_seq),
861 (unsigned long long)slot->ds_last_time, slot->ds_changed_samples,
862 slot->ds_equal_samples);
863
864 spin_lock(&o2hb_live_lock);
865
866 fire_callbacks:
867 /* dead nodes only come to life after some number of
868 * changes at any time during their dead time */
869 if (list_empty(&slot->ds_live_item) &&
870 slot->ds_changed_samples >= O2HB_LIVE_THRESHOLD) {
871 mlog(ML_HEARTBEAT, "Node %d (id 0x%llx) joined my region\n",
872 slot->ds_node_num, (long long)slot->ds_last_generation);
873
874 set_bit(slot->ds_node_num, reg->hr_live_node_bitmap);
875
876 /* first on the list generates a callback */
877 if (list_empty(&o2hb_live_slots[slot->ds_node_num])) {
878 mlog(ML_HEARTBEAT, "o2hb: Add node %d to live nodes "
879 "bitmap\n", slot->ds_node_num);
880 set_bit(slot->ds_node_num, o2hb_live_node_bitmap);
881
882 o2hb_queue_node_event(&event, O2HB_NODE_UP_CB, node,
883 slot->ds_node_num);
884
885 changed = 1;
886 }
887
888 list_add_tail(&slot->ds_live_item,
889 &o2hb_live_slots[slot->ds_node_num]);
890
891 slot->ds_equal_samples = 0;
892
893 /* We want to be sure that all nodes agree on the
894 * number of milliseconds before a node will be
895 * considered dead. The self-fencing timeout is
896 * computed from this value, and a discrepancy might
897 * result in heartbeat calling a node dead when it
898 * hasn't self-fenced yet. */
899 slot_dead_ms = le32_to_cpu(hb_block->hb_dead_ms);
900 if (slot_dead_ms && slot_dead_ms != dead_ms) {
901 /* TODO: Perhaps we can fail the region here. */
902 mlog(ML_ERROR, "Node %d on device %s has a dead count "
903 "of %u ms, but our count is %u ms.\n"
904 "Please double check your configuration values "
905 "for 'O2CB_HEARTBEAT_THRESHOLD'\n",
906 slot->ds_node_num, reg->hr_dev_name, slot_dead_ms,
907 dead_ms);
908 }
909 goto out;
910 }
911
912 /* if the list is dead, we're done.. */
913 if (list_empty(&slot->ds_live_item))
914 goto out;
915
916 /* live nodes only go dead after enough consequtive missed
917 * samples.. reset the missed counter whenever we see
918 * activity */
919 if (slot->ds_equal_samples >= o2hb_dead_threshold || gen_changed) {
920 mlog(ML_HEARTBEAT, "Node %d left my region\n",
921 slot->ds_node_num);
922
923 clear_bit(slot->ds_node_num, reg->hr_live_node_bitmap);
924
925 /* last off the live_slot generates a callback */
926 list_del_init(&slot->ds_live_item);
927 if (list_empty(&o2hb_live_slots[slot->ds_node_num])) {
928 mlog(ML_HEARTBEAT, "o2hb: Remove node %d from live "
929 "nodes bitmap\n", slot->ds_node_num);
930 clear_bit(slot->ds_node_num, o2hb_live_node_bitmap);
931
932 /* node can be null */
933 o2hb_queue_node_event(&event, O2HB_NODE_DOWN_CB,
934 node, slot->ds_node_num);
935
936 changed = 1;
937 }
938
939 /* We don't clear this because the node is still
940 * actually writing new blocks. */
941 if (!gen_changed)
942 slot->ds_changed_samples = 0;
943 goto out;
944 }
945 if (slot->ds_changed_samples) {
946 slot->ds_changed_samples = 0;
947 slot->ds_equal_samples = 0;
948 }
949 out:
950 spin_unlock(&o2hb_live_lock);
951
952 o2hb_run_event_list(&event);
953
954 if (node)
955 o2nm_node_put(node);
956 return changed;
957 }
958
959 /* This could be faster if we just implmented a find_last_bit, but I
960 * don't think the circumstances warrant it. */
961 static int o2hb_highest_node(unsigned long *nodes,
962 int numbits)
963 {
964 int highest, node;
965
966 highest = numbits;
967 node = -1;
968 while ((node = find_next_bit(nodes, numbits, node + 1)) != -1) {
969 if (node >= numbits)
970 break;
971
972 highest = node;
973 }
974
975 return highest;
976 }
977
978 static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
979 {
980 int i, ret, highest_node;
981 int membership_change = 0, own_slot_ok = 0;
982 unsigned long configured_nodes[BITS_TO_LONGS(O2NM_MAX_NODES)];
983 unsigned long live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
984 struct o2hb_bio_wait_ctxt write_wc;
985
986 ret = o2nm_configured_node_map(configured_nodes,
987 sizeof(configured_nodes));
988 if (ret) {
989 mlog_errno(ret);
990 goto bail;
991 }
992
993 /*
994 * If a node is not configured but is in the livemap, we still need
995 * to read the slot so as to be able to remove it from the livemap.
996 */
997 o2hb_fill_node_map(live_node_bitmap, sizeof(live_node_bitmap));
998 i = -1;
999 while ((i = find_next_bit(live_node_bitmap,
1000 O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) {
1001 set_bit(i, configured_nodes);
1002 }
1003
1004 highest_node = o2hb_highest_node(configured_nodes, O2NM_MAX_NODES);
1005 if (highest_node >= O2NM_MAX_NODES) {
1006 mlog(ML_NOTICE, "o2hb: No configured nodes found!\n");
1007 ret = -EINVAL;
1008 goto bail;
1009 }
1010
1011 /* No sense in reading the slots of nodes that don't exist
1012 * yet. Of course, if the node definitions have holes in them
1013 * then we're reading an empty slot anyway... Consider this
1014 * best-effort. */
1015 ret = o2hb_read_slots(reg, highest_node + 1);
1016 if (ret < 0) {
1017 mlog_errno(ret);
1018 goto bail;
1019 }
1020
1021 /* With an up to date view of the slots, we can check that no
1022 * other node has been improperly configured to heartbeat in
1023 * our slot. */
1024 own_slot_ok = o2hb_check_own_slot(reg);
1025
1026 /* fill in the proper info for our next heartbeat */
1027 o2hb_prepare_block(reg, reg->hr_generation);
1028
1029 ret = o2hb_issue_node_write(reg, &write_wc);
1030 if (ret < 0) {
1031 mlog_errno(ret);
1032 goto bail;
1033 }
1034
1035 i = -1;
1036 while((i = find_next_bit(configured_nodes,
1037 O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) {
1038 membership_change |= o2hb_check_slot(reg, &reg->hr_slots[i]);
1039 }
1040
1041 /*
1042 * We have to be sure we've advertised ourselves on disk
1043 * before we can go to steady state. This ensures that
1044 * people we find in our steady state have seen us.
1045 */
1046 o2hb_wait_on_io(reg, &write_wc);
1047 if (write_wc.wc_error) {
1048 /* Do not re-arm the write timeout on I/O error - we
1049 * can't be sure that the new block ever made it to
1050 * disk */
1051 mlog(ML_ERROR, "Write error %d on device \"%s\"\n",
1052 write_wc.wc_error, reg->hr_dev_name);
1053 ret = write_wc.wc_error;
1054 goto bail;
1055 }
1056
1057 /* Skip disarming the timeout if own slot has stale/bad data */
1058 if (own_slot_ok) {
1059 o2hb_set_quorum_device(reg);
1060 o2hb_arm_write_timeout(reg);
1061 }
1062
1063 bail:
1064 /* let the person who launched us know when things are steady */
1065 if (atomic_read(&reg->hr_steady_iterations) != 0) {
1066 if (!ret && own_slot_ok && !membership_change) {
1067 if (atomic_dec_and_test(&reg->hr_steady_iterations))
1068 wake_up(&o2hb_steady_queue);
1069 }
1070 }
1071
1072 if (atomic_read(&reg->hr_steady_iterations) != 0) {
1073 if (atomic_dec_and_test(&reg->hr_unsteady_iterations)) {
1074 printk(KERN_NOTICE "o2hb: Unable to stabilize "
1075 "heartbeart on region %s (%s)\n",
1076 config_item_name(&reg->hr_item),
1077 reg->hr_dev_name);
1078 atomic_set(&reg->hr_steady_iterations, 0);
1079 reg->hr_aborted_start = 1;
1080 wake_up(&o2hb_steady_queue);
1081 ret = -EIO;
1082 }
1083 }
1084
1085 return ret;
1086 }
1087
1088 /* Subtract b from a, storing the result in a. a *must* have a larger
1089 * value than b. */
1090 static void o2hb_tv_subtract(struct timeval *a,
1091 struct timeval *b)
1092 {
1093 /* just return 0 when a is after b */
1094 if (a->tv_sec < b->tv_sec ||
1095 (a->tv_sec == b->tv_sec && a->tv_usec < b->tv_usec)) {
1096 a->tv_sec = 0;
1097 a->tv_usec = 0;
1098 return;
1099 }
1100
1101 a->tv_sec -= b->tv_sec;
1102 a->tv_usec -= b->tv_usec;
1103 while ( a->tv_usec < 0 ) {
1104 a->tv_sec--;
1105 a->tv_usec += 1000000;
1106 }
1107 }
1108
1109 static unsigned int o2hb_elapsed_msecs(struct timeval *start,
1110 struct timeval *end)
1111 {
1112 struct timeval res = *end;
1113
1114 o2hb_tv_subtract(&res, start);
1115
1116 return res.tv_sec * 1000 + res.tv_usec / 1000;
1117 }
1118
1119 /*
1120 * we ride the region ref that the region dir holds. before the region
1121 * dir is removed and drops it ref it will wait to tear down this
1122 * thread.
1123 */
1124 static int o2hb_thread(void *data)
1125 {
1126 int i, ret;
1127 struct o2hb_region *reg = data;
1128 struct o2hb_bio_wait_ctxt write_wc;
1129 struct timeval before_hb, after_hb;
1130 unsigned int elapsed_msec;
1131
1132 mlog(ML_HEARTBEAT|ML_KTHREAD, "hb thread running\n");
1133
1134 set_user_nice(current, -20);
1135
1136 /* Pin node */
1137 o2nm_depend_this_node();
1138
1139 while (!kthread_should_stop() &&
1140 !reg->hr_unclean_stop && !reg->hr_aborted_start) {
1141 /* We track the time spent inside
1142 * o2hb_do_disk_heartbeat so that we avoid more than
1143 * hr_timeout_ms between disk writes. On busy systems
1144 * this should result in a heartbeat which is less
1145 * likely to time itself out. */
1146 do_gettimeofday(&before_hb);
1147
1148 ret = o2hb_do_disk_heartbeat(reg);
1149
1150 do_gettimeofday(&after_hb);
1151 elapsed_msec = o2hb_elapsed_msecs(&before_hb, &after_hb);
1152
1153 mlog(ML_HEARTBEAT,
1154 "start = %lu.%lu, end = %lu.%lu, msec = %u\n",
1155 before_hb.tv_sec, (unsigned long) before_hb.tv_usec,
1156 after_hb.tv_sec, (unsigned long) after_hb.tv_usec,
1157 elapsed_msec);
1158
1159 if (!kthread_should_stop() &&
1160 elapsed_msec < reg->hr_timeout_ms) {
1161 /* the kthread api has blocked signals for us so no
1162 * need to record the return value. */
1163 msleep_interruptible(reg->hr_timeout_ms - elapsed_msec);
1164 }
1165 }
1166
1167 o2hb_disarm_write_timeout(reg);
1168
1169 /* unclean stop is only used in very bad situation */
1170 for(i = 0; !reg->hr_unclean_stop && i < reg->hr_blocks; i++)
1171 o2hb_shutdown_slot(&reg->hr_slots[i]);
1172
1173 /* Explicit down notification - avoid forcing the other nodes
1174 * to timeout on this region when we could just as easily
1175 * write a clear generation - thus indicating to them that
1176 * this node has left this region.
1177 */
1178 if (!reg->hr_unclean_stop && !reg->hr_aborted_start) {
1179 o2hb_prepare_block(reg, 0);
1180 ret = o2hb_issue_node_write(reg, &write_wc);
1181 if (ret == 0)
1182 o2hb_wait_on_io(reg, &write_wc);
1183 else
1184 mlog_errno(ret);
1185 }
1186
1187 /* Unpin node */
1188 o2nm_undepend_this_node();
1189
1190 mlog(ML_HEARTBEAT|ML_KTHREAD, "o2hb thread exiting\n");
1191
1192 return 0;
1193 }
1194
1195 #ifdef CONFIG_DEBUG_FS
1196 static int o2hb_debug_open(struct inode *inode, struct file *file)
1197 {
1198 struct o2hb_debug_buf *db = inode->i_private;
1199 struct o2hb_region *reg;
1200 unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)];
1201 unsigned long lts;
1202 char *buf = NULL;
1203 int i = -1;
1204 int out = 0;
1205
1206 /* max_nodes should be the largest bitmap we pass here */
1207 BUG_ON(sizeof(map) < db->db_size);
1208
1209 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1210 if (!buf)
1211 goto bail;
1212
1213 switch (db->db_type) {
1214 case O2HB_DB_TYPE_LIVENODES:
1215 case O2HB_DB_TYPE_LIVEREGIONS:
1216 case O2HB_DB_TYPE_QUORUMREGIONS:
1217 case O2HB_DB_TYPE_FAILEDREGIONS:
1218 spin_lock(&o2hb_live_lock);
1219 memcpy(map, db->db_data, db->db_size);
1220 spin_unlock(&o2hb_live_lock);
1221 break;
1222
1223 case O2HB_DB_TYPE_REGION_LIVENODES:
1224 spin_lock(&o2hb_live_lock);
1225 reg = (struct o2hb_region *)db->db_data;
1226 memcpy(map, reg->hr_live_node_bitmap, db->db_size);
1227 spin_unlock(&o2hb_live_lock);
1228 break;
1229
1230 case O2HB_DB_TYPE_REGION_NUMBER:
1231 reg = (struct o2hb_region *)db->db_data;
1232 out += snprintf(buf + out, PAGE_SIZE - out, "%d\n",
1233 reg->hr_region_num);
1234 goto done;
1235
1236 case O2HB_DB_TYPE_REGION_ELAPSED_TIME:
1237 reg = (struct o2hb_region *)db->db_data;
1238 lts = reg->hr_last_timeout_start;
1239 /* If 0, it has never been set before */
1240 if (lts)
1241 lts = jiffies_to_msecs(jiffies - lts);
1242 out += snprintf(buf + out, PAGE_SIZE - out, "%lu\n", lts);
1243 goto done;
1244
1245 case O2HB_DB_TYPE_REGION_PINNED:
1246 reg = (struct o2hb_region *)db->db_data;
1247 out += snprintf(buf + out, PAGE_SIZE - out, "%u\n",
1248 !!reg->hr_item_pinned);
1249 goto done;
1250
1251 default:
1252 goto done;
1253 }
1254
1255 while ((i = find_next_bit(map, db->db_len, i + 1)) < db->db_len)
1256 out += snprintf(buf + out, PAGE_SIZE - out, "%d ", i);
1257 out += snprintf(buf + out, PAGE_SIZE - out, "\n");
1258
1259 done:
1260 i_size_write(inode, out);
1261
1262 file->private_data = buf;
1263
1264 return 0;
1265 bail:
1266 return -ENOMEM;
1267 }
1268
1269 static int o2hb_debug_release(struct inode *inode, struct file *file)
1270 {
1271 kfree(file->private_data);
1272 return 0;
1273 }
1274
1275 static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
1276 size_t nbytes, loff_t *ppos)
1277 {
1278 return simple_read_from_buffer(buf, nbytes, ppos, file->private_data,
1279 i_size_read(file->f_mapping->host));
1280 }
1281 #else
1282 static int o2hb_debug_open(struct inode *inode, struct file *file)
1283 {
1284 return 0;
1285 }
1286 static int o2hb_debug_release(struct inode *inode, struct file *file)
1287 {
1288 return 0;
1289 }
1290 static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
1291 size_t nbytes, loff_t *ppos)
1292 {
1293 return 0;
1294 }
1295 #endif /* CONFIG_DEBUG_FS */
1296
1297 static const struct file_operations o2hb_debug_fops = {
1298 .open = o2hb_debug_open,
1299 .release = o2hb_debug_release,
1300 .read = o2hb_debug_read,
1301 .llseek = generic_file_llseek,
1302 };
1303
1304 void o2hb_exit(void)
1305 {
1306 kfree(o2hb_db_livenodes);
1307 kfree(o2hb_db_liveregions);
1308 kfree(o2hb_db_quorumregions);
1309 kfree(o2hb_db_failedregions);
1310 debugfs_remove(o2hb_debug_failedregions);
1311 debugfs_remove(o2hb_debug_quorumregions);
1312 debugfs_remove(o2hb_debug_liveregions);
1313 debugfs_remove(o2hb_debug_livenodes);
1314 debugfs_remove(o2hb_debug_dir);
1315 }
1316
1317 static struct dentry *o2hb_debug_create(const char *name, struct dentry *dir,
1318 struct o2hb_debug_buf **db, int db_len,
1319 int type, int size, int len, void *data)
1320 {
1321 *db = kmalloc(db_len, GFP_KERNEL);
1322 if (!*db)
1323 return NULL;
1324
1325 (*db)->db_type = type;
1326 (*db)->db_size = size;
1327 (*db)->db_len = len;
1328 (*db)->db_data = data;
1329
1330 return debugfs_create_file(name, S_IFREG|S_IRUSR, dir, *db,
1331 &o2hb_debug_fops);
1332 }
1333
1334 static int o2hb_debug_init(void)
1335 {
1336 int ret = -ENOMEM;
1337
1338 o2hb_debug_dir = debugfs_create_dir(O2HB_DEBUG_DIR, NULL);
1339 if (!o2hb_debug_dir) {
1340 mlog_errno(ret);
1341 goto bail;
1342 }
1343
1344 o2hb_debug_livenodes = o2hb_debug_create(O2HB_DEBUG_LIVENODES,
1345 o2hb_debug_dir,
1346 &o2hb_db_livenodes,
1347 sizeof(*o2hb_db_livenodes),
1348 O2HB_DB_TYPE_LIVENODES,
1349 sizeof(o2hb_live_node_bitmap),
1350 O2NM_MAX_NODES,
1351 o2hb_live_node_bitmap);
1352 if (!o2hb_debug_livenodes) {
1353 mlog_errno(ret);
1354 goto bail;
1355 }
1356
1357 o2hb_debug_liveregions = o2hb_debug_create(O2HB_DEBUG_LIVEREGIONS,
1358 o2hb_debug_dir,
1359 &o2hb_db_liveregions,
1360 sizeof(*o2hb_db_liveregions),
1361 O2HB_DB_TYPE_LIVEREGIONS,
1362 sizeof(o2hb_live_region_bitmap),
1363 O2NM_MAX_REGIONS,
1364 o2hb_live_region_bitmap);
1365 if (!o2hb_debug_liveregions) {
1366 mlog_errno(ret);
1367 goto bail;
1368 }
1369
1370 o2hb_debug_quorumregions =
1371 o2hb_debug_create(O2HB_DEBUG_QUORUMREGIONS,
1372 o2hb_debug_dir,
1373 &o2hb_db_quorumregions,
1374 sizeof(*o2hb_db_quorumregions),
1375 O2HB_DB_TYPE_QUORUMREGIONS,
1376 sizeof(o2hb_quorum_region_bitmap),
1377 O2NM_MAX_REGIONS,
1378 o2hb_quorum_region_bitmap);
1379 if (!o2hb_debug_quorumregions) {
1380 mlog_errno(ret);
1381 goto bail;
1382 }
1383
1384 o2hb_debug_failedregions =
1385 o2hb_debug_create(O2HB_DEBUG_FAILEDREGIONS,
1386 o2hb_debug_dir,
1387 &o2hb_db_failedregions,
1388 sizeof(*o2hb_db_failedregions),
1389 O2HB_DB_TYPE_FAILEDREGIONS,
1390 sizeof(o2hb_failed_region_bitmap),
1391 O2NM_MAX_REGIONS,
1392 o2hb_failed_region_bitmap);
1393 if (!o2hb_debug_failedregions) {
1394 mlog_errno(ret);
1395 goto bail;
1396 }
1397
1398 ret = 0;
1399 bail:
1400 if (ret)
1401 o2hb_exit();
1402
1403 return ret;
1404 }
1405
1406 int o2hb_init(void)
1407 {
1408 int i;
1409
1410 for (i = 0; i < ARRAY_SIZE(o2hb_callbacks); i++)
1411 INIT_LIST_HEAD(&o2hb_callbacks[i].list);
1412
1413 for (i = 0; i < ARRAY_SIZE(o2hb_live_slots); i++)
1414 INIT_LIST_HEAD(&o2hb_live_slots[i]);
1415
1416 INIT_LIST_HEAD(&o2hb_node_events);
1417
1418 memset(o2hb_live_node_bitmap, 0, sizeof(o2hb_live_node_bitmap));
1419 memset(o2hb_region_bitmap, 0, sizeof(o2hb_region_bitmap));
1420 memset(o2hb_live_region_bitmap, 0, sizeof(o2hb_live_region_bitmap));
1421 memset(o2hb_quorum_region_bitmap, 0, sizeof(o2hb_quorum_region_bitmap));
1422 memset(o2hb_failed_region_bitmap, 0, sizeof(o2hb_failed_region_bitmap));
1423
1424 o2hb_dependent_users = 0;
1425
1426 return o2hb_debug_init();
1427 }
1428
1429 /* if we're already in a callback then we're already serialized by the sem */
1430 static void o2hb_fill_node_map_from_callback(unsigned long *map,
1431 unsigned bytes)
1432 {
1433 BUG_ON(bytes < (BITS_TO_LONGS(O2NM_MAX_NODES) * sizeof(unsigned long)));
1434
1435 memcpy(map, &o2hb_live_node_bitmap, bytes);
1436 }
1437
1438 /*
1439 * get a map of all nodes that are heartbeating in any regions
1440 */
1441 void o2hb_fill_node_map(unsigned long *map, unsigned bytes)
1442 {
1443 /* callers want to serialize this map and callbacks so that they
1444 * can trust that they don't miss nodes coming to the party */
1445 down_read(&o2hb_callback_sem);
1446 spin_lock(&o2hb_live_lock);
1447 o2hb_fill_node_map_from_callback(map, bytes);
1448 spin_unlock(&o2hb_live_lock);
1449 up_read(&o2hb_callback_sem);
1450 }
1451 EXPORT_SYMBOL_GPL(o2hb_fill_node_map);
1452
1453 /*
1454 * heartbeat configfs bits. The heartbeat set is a default set under
1455 * the cluster set in nodemanager.c.
1456 */
1457
1458 static struct o2hb_region *to_o2hb_region(struct config_item *item)
1459 {
1460 return item ? container_of(item, struct o2hb_region, hr_item) : NULL;
1461 }
1462
1463 /* drop_item only drops its ref after killing the thread, nothing should
1464 * be using the region anymore. this has to clean up any state that
1465 * attributes might have built up. */
1466 static void o2hb_region_release(struct config_item *item)
1467 {
1468 int i;
1469 struct page *page;
1470 struct o2hb_region *reg = to_o2hb_region(item);
1471
1472 mlog(ML_HEARTBEAT, "hb region release (%s)\n", reg->hr_dev_name);
1473
1474 if (reg->hr_tmp_block)
1475 kfree(reg->hr_tmp_block);
1476
1477 if (reg->hr_slot_data) {
1478 for (i = 0; i < reg->hr_num_pages; i++) {
1479 page = reg->hr_slot_data[i];
1480 if (page)
1481 __free_page(page);
1482 }
1483 kfree(reg->hr_slot_data);
1484 }
1485
1486 if (reg->hr_bdev)
1487 blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE);
1488
1489 if (reg->hr_slots)
1490 kfree(reg->hr_slots);
1491
1492 kfree(reg->hr_db_regnum);
1493 kfree(reg->hr_db_livenodes);
1494 debugfs_remove(reg->hr_debug_livenodes);
1495 debugfs_remove(reg->hr_debug_regnum);
1496 debugfs_remove(reg->hr_debug_elapsed_time);
1497 debugfs_remove(reg->hr_debug_pinned);
1498 debugfs_remove(reg->hr_debug_dir);
1499
1500 spin_lock(&o2hb_live_lock);
1501 list_del(&reg->hr_all_item);
1502 spin_unlock(&o2hb_live_lock);
1503
1504 kfree(reg);
1505 }
1506
1507 static int o2hb_read_block_input(struct o2hb_region *reg,
1508 const char *page,
1509 size_t count,
1510 unsigned long *ret_bytes,
1511 unsigned int *ret_bits)
1512 {
1513 unsigned long bytes;
1514 char *p = (char *)page;
1515
1516 bytes = simple_strtoul(p, &p, 0);
1517 if (!p || (*p && (*p != '\n')))
1518 return -EINVAL;
1519
1520 /* Heartbeat and fs min / max block sizes are the same. */
1521 if (bytes > 4096 || bytes < 512)
1522 return -ERANGE;
1523 if (hweight16(bytes) != 1)
1524 return -EINVAL;
1525
1526 if (ret_bytes)
1527 *ret_bytes = bytes;
1528 if (ret_bits)
1529 *ret_bits = ffs(bytes) - 1;
1530
1531 return 0;
1532 }
1533
1534 static ssize_t o2hb_region_block_bytes_read(struct o2hb_region *reg,
1535 char *page)
1536 {
1537 return sprintf(page, "%u\n", reg->hr_block_bytes);
1538 }
1539
1540 static ssize_t o2hb_region_block_bytes_write(struct o2hb_region *reg,
1541 const char *page,
1542 size_t count)
1543 {
1544 int status;
1545 unsigned long block_bytes;
1546 unsigned int block_bits;
1547
1548 if (reg->hr_bdev)
1549 return -EINVAL;
1550
1551 status = o2hb_read_block_input(reg, page, count,
1552 &block_bytes, &block_bits);
1553 if (status)
1554 return status;
1555
1556 reg->hr_block_bytes = (unsigned int)block_bytes;
1557 reg->hr_block_bits = block_bits;
1558
1559 return count;
1560 }
1561
1562 static ssize_t o2hb_region_start_block_read(struct o2hb_region *reg,
1563 char *page)
1564 {
1565 return sprintf(page, "%llu\n", reg->hr_start_block);
1566 }
1567
1568 static ssize_t o2hb_region_start_block_write(struct o2hb_region *reg,
1569 const char *page,
1570 size_t count)
1571 {
1572 unsigned long long tmp;
1573 char *p = (char *)page;
1574
1575 if (reg->hr_bdev)
1576 return -EINVAL;
1577
1578 tmp = simple_strtoull(p, &p, 0);
1579 if (!p || (*p && (*p != '\n')))
1580 return -EINVAL;
1581
1582 reg->hr_start_block = tmp;
1583
1584 return count;
1585 }
1586
1587 static ssize_t o2hb_region_blocks_read(struct o2hb_region *reg,
1588 char *page)
1589 {
1590 return sprintf(page, "%d\n", reg->hr_blocks);
1591 }
1592
1593 static ssize_t o2hb_region_blocks_write(struct o2hb_region *reg,
1594 const char *page,
1595 size_t count)
1596 {
1597 unsigned long tmp;
1598 char *p = (char *)page;
1599
1600 if (reg->hr_bdev)
1601 return -EINVAL;
1602
1603 tmp = simple_strtoul(p, &p, 0);
1604 if (!p || (*p && (*p != '\n')))
1605 return -EINVAL;
1606
1607 if (tmp > O2NM_MAX_NODES || tmp == 0)
1608 return -ERANGE;
1609
1610 reg->hr_blocks = (unsigned int)tmp;
1611
1612 return count;
1613 }
1614
1615 static ssize_t o2hb_region_dev_read(struct o2hb_region *reg,
1616 char *page)
1617 {
1618 unsigned int ret = 0;
1619
1620 if (reg->hr_bdev)
1621 ret = sprintf(page, "%s\n", reg->hr_dev_name);
1622
1623 return ret;
1624 }
1625
1626 static void o2hb_init_region_params(struct o2hb_region *reg)
1627 {
1628 reg->hr_slots_per_page = PAGE_CACHE_SIZE >> reg->hr_block_bits;
1629 reg->hr_timeout_ms = O2HB_REGION_TIMEOUT_MS;
1630
1631 mlog(ML_HEARTBEAT, "hr_start_block = %llu, hr_blocks = %u\n",
1632 reg->hr_start_block, reg->hr_blocks);
1633 mlog(ML_HEARTBEAT, "hr_block_bytes = %u, hr_block_bits = %u\n",
1634 reg->hr_block_bytes, reg->hr_block_bits);
1635 mlog(ML_HEARTBEAT, "hr_timeout_ms = %u\n", reg->hr_timeout_ms);
1636 mlog(ML_HEARTBEAT, "dead threshold = %u\n", o2hb_dead_threshold);
1637 }
1638
1639 static int o2hb_map_slot_data(struct o2hb_region *reg)
1640 {
1641 int i, j;
1642 unsigned int last_slot;
1643 unsigned int spp = reg->hr_slots_per_page;
1644 struct page *page;
1645 char *raw;
1646 struct o2hb_disk_slot *slot;
1647
1648 reg->hr_tmp_block = kmalloc(reg->hr_block_bytes, GFP_KERNEL);
1649 if (reg->hr_tmp_block == NULL) {
1650 mlog_errno(-ENOMEM);
1651 return -ENOMEM;
1652 }
1653
1654 reg->hr_slots = kcalloc(reg->hr_blocks,
1655 sizeof(struct o2hb_disk_slot), GFP_KERNEL);
1656 if (reg->hr_slots == NULL) {
1657 mlog_errno(-ENOMEM);
1658 return -ENOMEM;
1659 }
1660
1661 for(i = 0; i < reg->hr_blocks; i++) {
1662 slot = &reg->hr_slots[i];
1663 slot->ds_node_num = i;
1664 INIT_LIST_HEAD(&slot->ds_live_item);
1665 slot->ds_raw_block = NULL;
1666 }
1667
1668 reg->hr_num_pages = (reg->hr_blocks + spp - 1) / spp;
1669 mlog(ML_HEARTBEAT, "Going to require %u pages to cover %u blocks "
1670 "at %u blocks per page\n",
1671 reg->hr_num_pages, reg->hr_blocks, spp);
1672
1673 reg->hr_slot_data = kcalloc(reg->hr_num_pages, sizeof(struct page *),
1674 GFP_KERNEL);
1675 if (!reg->hr_slot_data) {
1676 mlog_errno(-ENOMEM);
1677 return -ENOMEM;
1678 }
1679
1680 for(i = 0; i < reg->hr_num_pages; i++) {
1681 page = alloc_page(GFP_KERNEL);
1682 if (!page) {
1683 mlog_errno(-ENOMEM);
1684 return -ENOMEM;
1685 }
1686
1687 reg->hr_slot_data[i] = page;
1688
1689 last_slot = i * spp;
1690 raw = page_address(page);
1691 for (j = 0;
1692 (j < spp) && ((j + last_slot) < reg->hr_blocks);
1693 j++) {
1694 BUG_ON((j + last_slot) >= reg->hr_blocks);
1695
1696 slot = &reg->hr_slots[j + last_slot];
1697 slot->ds_raw_block =
1698 (struct o2hb_disk_heartbeat_block *) raw;
1699
1700 raw += reg->hr_block_bytes;
1701 }
1702 }
1703
1704 return 0;
1705 }
1706
1707 /* Read in all the slots available and populate the tracking
1708 * structures so that we can start with a baseline idea of what's
1709 * there. */
1710 static int o2hb_populate_slot_data(struct o2hb_region *reg)
1711 {
1712 int ret, i;
1713 struct o2hb_disk_slot *slot;
1714 struct o2hb_disk_heartbeat_block *hb_block;
1715
1716 ret = o2hb_read_slots(reg, reg->hr_blocks);
1717 if (ret) {
1718 mlog_errno(ret);
1719 goto out;
1720 }
1721
1722 /* We only want to get an idea of the values initially in each
1723 * slot, so we do no verification - o2hb_check_slot will
1724 * actually determine if each configured slot is valid and
1725 * whether any values have changed. */
1726 for(i = 0; i < reg->hr_blocks; i++) {
1727 slot = &reg->hr_slots[i];
1728 hb_block = (struct o2hb_disk_heartbeat_block *) slot->ds_raw_block;
1729
1730 /* Only fill the values that o2hb_check_slot uses to
1731 * determine changing slots */
1732 slot->ds_last_time = le64_to_cpu(hb_block->hb_seq);
1733 slot->ds_last_generation = le64_to_cpu(hb_block->hb_generation);
1734 }
1735
1736 out:
1737 return ret;
1738 }
1739
1740 /* this is acting as commit; we set up all of hr_bdev and hr_task or nothing */
1741 static ssize_t o2hb_region_dev_write(struct o2hb_region *reg,
1742 const char *page,
1743 size_t count)
1744 {
1745 struct task_struct *hb_task;
1746 long fd;
1747 int sectsize;
1748 char *p = (char *)page;
1749 struct file *filp = NULL;
1750 struct inode *inode = NULL;
1751 ssize_t ret = -EINVAL;
1752 int live_threshold;
1753
1754 if (reg->hr_bdev)
1755 goto out;
1756
1757 /* We can't heartbeat without having had our node number
1758 * configured yet. */
1759 if (o2nm_this_node() == O2NM_MAX_NODES)
1760 goto out;
1761
1762 fd = simple_strtol(p, &p, 0);
1763 if (!p || (*p && (*p != '\n')))
1764 goto out;
1765
1766 if (fd < 0 || fd >= INT_MAX)
1767 goto out;
1768
1769 filp = fget(fd);
1770 if (filp == NULL)
1771 goto out;
1772
1773 if (reg->hr_blocks == 0 || reg->hr_start_block == 0 ||
1774 reg->hr_block_bytes == 0)
1775 goto out;
1776
1777 inode = igrab(filp->f_mapping->host);
1778 if (inode == NULL)
1779 goto out;
1780
1781 if (!S_ISBLK(inode->i_mode))
1782 goto out;
1783
1784 reg->hr_bdev = I_BDEV(filp->f_mapping->host);
1785 ret = blkdev_get(reg->hr_bdev, FMODE_WRITE | FMODE_READ, NULL);
1786 if (ret) {
1787 reg->hr_bdev = NULL;
1788 goto out;
1789 }
1790 inode = NULL;
1791
1792 bdevname(reg->hr_bdev, reg->hr_dev_name);
1793
1794 sectsize = bdev_logical_block_size(reg->hr_bdev);
1795 if (sectsize != reg->hr_block_bytes) {
1796 mlog(ML_ERROR,
1797 "blocksize %u incorrect for device, expected %d",
1798 reg->hr_block_bytes, sectsize);
1799 ret = -EINVAL;
1800 goto out;
1801 }
1802
1803 o2hb_init_region_params(reg);
1804
1805 /* Generation of zero is invalid */
1806 do {
1807 get_random_bytes(&reg->hr_generation,
1808 sizeof(reg->hr_generation));
1809 } while (reg->hr_generation == 0);
1810
1811 ret = o2hb_map_slot_data(reg);
1812 if (ret) {
1813 mlog_errno(ret);
1814 goto out;
1815 }
1816
1817 ret = o2hb_populate_slot_data(reg);
1818 if (ret) {
1819 mlog_errno(ret);
1820 goto out;
1821 }
1822
1823 INIT_DELAYED_WORK(&reg->hr_write_timeout_work, o2hb_write_timeout);
1824
1825 /*
1826 * A node is considered live after it has beat LIVE_THRESHOLD
1827 * times. We're not steady until we've given them a chance
1828 * _after_ our first read.
1829 * The default threshold is bare minimum so as to limit the delay
1830 * during mounts. For global heartbeat, the threshold doubled for the
1831 * first region.
1832 */
1833 live_threshold = O2HB_LIVE_THRESHOLD;
1834 if (o2hb_global_heartbeat_active()) {
1835 spin_lock(&o2hb_live_lock);
1836 if (o2hb_pop_count(&o2hb_region_bitmap, O2NM_MAX_REGIONS) == 1)
1837 live_threshold <<= 1;
1838 spin_unlock(&o2hb_live_lock);
1839 }
1840 ++live_threshold;
1841 atomic_set(&reg->hr_steady_iterations, live_threshold);
1842 /* unsteady_iterations is double the steady_iterations */
1843 atomic_set(&reg->hr_unsteady_iterations, (live_threshold << 1));
1844
1845 hb_task = kthread_run(o2hb_thread, reg, "o2hb-%s",
1846 reg->hr_item.ci_name);
1847 if (IS_ERR(hb_task)) {
1848 ret = PTR_ERR(hb_task);
1849 mlog_errno(ret);
1850 goto out;
1851 }
1852
1853 spin_lock(&o2hb_live_lock);
1854 reg->hr_task = hb_task;
1855 spin_unlock(&o2hb_live_lock);
1856
1857 ret = wait_event_interruptible(o2hb_steady_queue,
1858 atomic_read(&reg->hr_steady_iterations) == 0);
1859 if (ret) {
1860 atomic_set(&reg->hr_steady_iterations, 0);
1861 reg->hr_aborted_start = 1;
1862 }
1863
1864 if (reg->hr_aborted_start) {
1865 ret = -EIO;
1866 goto out;
1867 }
1868
1869 /* Ok, we were woken. Make sure it wasn't by drop_item() */
1870 spin_lock(&o2hb_live_lock);
1871 hb_task = reg->hr_task;
1872 if (o2hb_global_heartbeat_active())
1873 set_bit(reg->hr_region_num, o2hb_live_region_bitmap);
1874 spin_unlock(&o2hb_live_lock);
1875
1876 if (hb_task)
1877 ret = count;
1878 else
1879 ret = -EIO;
1880
1881 if (hb_task && o2hb_global_heartbeat_active())
1882 printk(KERN_NOTICE "o2hb: Heartbeat started on region %s (%s)\n",
1883 config_item_name(&reg->hr_item), reg->hr_dev_name);
1884
1885 out:
1886 if (filp)
1887 fput(filp);
1888 if (inode)
1889 iput(inode);
1890 if (ret < 0) {
1891 if (reg->hr_bdev) {
1892 blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE);
1893 reg->hr_bdev = NULL;
1894 }
1895 }
1896 return ret;
1897 }
1898
1899 static ssize_t o2hb_region_pid_read(struct o2hb_region *reg,
1900 char *page)
1901 {
1902 pid_t pid = 0;
1903
1904 spin_lock(&o2hb_live_lock);
1905 if (reg->hr_task)
1906 pid = task_pid_nr(reg->hr_task);
1907 spin_unlock(&o2hb_live_lock);
1908
1909 if (!pid)
1910 return 0;
1911
1912 return sprintf(page, "%u\n", pid);
1913 }
1914
1915 struct o2hb_region_attribute {
1916 struct configfs_attribute attr;
1917 ssize_t (*show)(struct o2hb_region *, char *);
1918 ssize_t (*store)(struct o2hb_region *, const char *, size_t);
1919 };
1920
1921 static struct o2hb_region_attribute o2hb_region_attr_block_bytes = {
1922 .attr = { .ca_owner = THIS_MODULE,
1923 .ca_name = "block_bytes",
1924 .ca_mode = S_IRUGO | S_IWUSR },
1925 .show = o2hb_region_block_bytes_read,
1926 .store = o2hb_region_block_bytes_write,
1927 };
1928
1929 static struct o2hb_region_attribute o2hb_region_attr_start_block = {
1930 .attr = { .ca_owner = THIS_MODULE,
1931 .ca_name = "start_block",
1932 .ca_mode = S_IRUGO | S_IWUSR },
1933 .show = o2hb_region_start_block_read,
1934 .store = o2hb_region_start_block_write,
1935 };
1936
1937 static struct o2hb_region_attribute o2hb_region_attr_blocks = {
1938 .attr = { .ca_owner = THIS_MODULE,
1939 .ca_name = "blocks",
1940 .ca_mode = S_IRUGO | S_IWUSR },
1941 .show = o2hb_region_blocks_read,
1942 .store = o2hb_region_blocks_write,
1943 };
1944
1945 static struct o2hb_region_attribute o2hb_region_attr_dev = {
1946 .attr = { .ca_owner = THIS_MODULE,
1947 .ca_name = "dev",
1948 .ca_mode = S_IRUGO | S_IWUSR },
1949 .show = o2hb_region_dev_read,
1950 .store = o2hb_region_dev_write,
1951 };
1952
1953 static struct o2hb_region_attribute o2hb_region_attr_pid = {
1954 .attr = { .ca_owner = THIS_MODULE,
1955 .ca_name = "pid",
1956 .ca_mode = S_IRUGO | S_IRUSR },
1957 .show = o2hb_region_pid_read,
1958 };
1959
1960 static struct configfs_attribute *o2hb_region_attrs[] = {
1961 &o2hb_region_attr_block_bytes.attr,
1962 &o2hb_region_attr_start_block.attr,
1963 &o2hb_region_attr_blocks.attr,
1964 &o2hb_region_attr_dev.attr,
1965 &o2hb_region_attr_pid.attr,
1966 NULL,
1967 };
1968
1969 static ssize_t o2hb_region_show(struct config_item *item,
1970 struct configfs_attribute *attr,
1971 char *page)
1972 {
1973 struct o2hb_region *reg = to_o2hb_region(item);
1974 struct o2hb_region_attribute *o2hb_region_attr =
1975 container_of(attr, struct o2hb_region_attribute, attr);
1976 ssize_t ret = 0;
1977
1978 if (o2hb_region_attr->show)
1979 ret = o2hb_region_attr->show(reg, page);
1980 return ret;
1981 }
1982
1983 static ssize_t o2hb_region_store(struct config_item *item,
1984 struct configfs_attribute *attr,
1985 const char *page, size_t count)
1986 {
1987 struct o2hb_region *reg = to_o2hb_region(item);
1988 struct o2hb_region_attribute *o2hb_region_attr =
1989 container_of(attr, struct o2hb_region_attribute, attr);
1990 ssize_t ret = -EINVAL;
1991
1992 if (o2hb_region_attr->store)
1993 ret = o2hb_region_attr->store(reg, page, count);
1994 return ret;
1995 }
1996
1997 static struct configfs_item_operations o2hb_region_item_ops = {
1998 .release = o2hb_region_release,
1999 .show_attribute = o2hb_region_show,
2000 .store_attribute = o2hb_region_store,
2001 };
2002
2003 static struct config_item_type o2hb_region_type = {
2004 .ct_item_ops = &o2hb_region_item_ops,
2005 .ct_attrs = o2hb_region_attrs,
2006 .ct_owner = THIS_MODULE,
2007 };
2008
2009 /* heartbeat set */
2010
2011 struct o2hb_heartbeat_group {
2012 struct config_group hs_group;
2013 /* some stuff? */
2014 };
2015
2016 static struct o2hb_heartbeat_group *to_o2hb_heartbeat_group(struct config_group *group)
2017 {
2018 return group ?
2019 container_of(group, struct o2hb_heartbeat_group, hs_group)
2020 : NULL;
2021 }
2022
2023 static int o2hb_debug_region_init(struct o2hb_region *reg, struct dentry *dir)
2024 {
2025 int ret = -ENOMEM;
2026
2027 reg->hr_debug_dir =
2028 debugfs_create_dir(config_item_name(&reg->hr_item), dir);
2029 if (!reg->hr_debug_dir) {
2030 mlog_errno(ret);
2031 goto bail;
2032 }
2033
2034 reg->hr_debug_livenodes =
2035 o2hb_debug_create(O2HB_DEBUG_LIVENODES,
2036 reg->hr_debug_dir,
2037 &(reg->hr_db_livenodes),
2038 sizeof(*(reg->hr_db_livenodes)),
2039 O2HB_DB_TYPE_REGION_LIVENODES,
2040 sizeof(reg->hr_live_node_bitmap),
2041 O2NM_MAX_NODES, reg);
2042 if (!reg->hr_debug_livenodes) {
2043 mlog_errno(ret);
2044 goto bail;
2045 }
2046
2047 reg->hr_debug_regnum =
2048 o2hb_debug_create(O2HB_DEBUG_REGION_NUMBER,
2049 reg->hr_debug_dir,
2050 &(reg->hr_db_regnum),
2051 sizeof(*(reg->hr_db_regnum)),
2052 O2HB_DB_TYPE_REGION_NUMBER,
2053 0, O2NM_MAX_NODES, reg);
2054 if (!reg->hr_debug_regnum) {
2055 mlog_errno(ret);
2056 goto bail;
2057 }
2058
2059 reg->hr_debug_elapsed_time =
2060 o2hb_debug_create(O2HB_DEBUG_REGION_ELAPSED_TIME,
2061 reg->hr_debug_dir,
2062 &(reg->hr_db_elapsed_time),
2063 sizeof(*(reg->hr_db_elapsed_time)),
2064 O2HB_DB_TYPE_REGION_ELAPSED_TIME,
2065 0, 0, reg);
2066 if (!reg->hr_debug_elapsed_time) {
2067 mlog_errno(ret);
2068 goto bail;
2069 }
2070
2071 reg->hr_debug_pinned =
2072 o2hb_debug_create(O2HB_DEBUG_REGION_PINNED,
2073 reg->hr_debug_dir,
2074 &(reg->hr_db_pinned),
2075 sizeof(*(reg->hr_db_pinned)),
2076 O2HB_DB_TYPE_REGION_PINNED,
2077 0, 0, reg);
2078 if (!reg->hr_debug_pinned) {
2079 mlog_errno(ret);
2080 goto bail;
2081 }
2082
2083 ret = 0;
2084 bail:
2085 return ret;
2086 }
2087
2088 static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *group,
2089 const char *name)
2090 {
2091 struct o2hb_region *reg = NULL;
2092 int ret;
2093
2094 reg = kzalloc(sizeof(struct o2hb_region), GFP_KERNEL);
2095 if (reg == NULL)
2096 return ERR_PTR(-ENOMEM);
2097
2098 if (strlen(name) > O2HB_MAX_REGION_NAME_LEN) {
2099 ret = -ENAMETOOLONG;
2100 goto free;
2101 }
2102
2103 spin_lock(&o2hb_live_lock);
2104 reg->hr_region_num = 0;
2105 if (o2hb_global_heartbeat_active()) {
2106 reg->hr_region_num = find_first_zero_bit(o2hb_region_bitmap,
2107 O2NM_MAX_REGIONS);
2108 if (reg->hr_region_num >= O2NM_MAX_REGIONS) {
2109 spin_unlock(&o2hb_live_lock);
2110 ret = -EFBIG;
2111 goto free;
2112 }
2113 set_bit(reg->hr_region_num, o2hb_region_bitmap);
2114 }
2115 list_add_tail(&reg->hr_all_item, &o2hb_all_regions);
2116 spin_unlock(&o2hb_live_lock);
2117
2118 config_item_init_type_name(&reg->hr_item, name, &o2hb_region_type);
2119
2120 ret = o2hb_debug_region_init(reg, o2hb_debug_dir);
2121 if (ret) {
2122 config_item_put(&reg->hr_item);
2123 goto free;
2124 }
2125
2126 return &reg->hr_item;
2127 free:
2128 kfree(reg);
2129 return ERR_PTR(ret);
2130 }
2131
2132 static void o2hb_heartbeat_group_drop_item(struct config_group *group,
2133 struct config_item *item)
2134 {
2135 struct task_struct *hb_task;
2136 struct o2hb_region *reg = to_o2hb_region(item);
2137 int quorum_region = 0;
2138
2139 /* stop the thread when the user removes the region dir */
2140 spin_lock(&o2hb_live_lock);
2141 hb_task = reg->hr_task;
2142 reg->hr_task = NULL;
2143 reg->hr_item_dropped = 1;
2144 spin_unlock(&o2hb_live_lock);
2145
2146 if (hb_task)
2147 kthread_stop(hb_task);
2148
2149 if (o2hb_global_heartbeat_active()) {
2150 spin_lock(&o2hb_live_lock);
2151 clear_bit(reg->hr_region_num, o2hb_region_bitmap);
2152 clear_bit(reg->hr_region_num, o2hb_live_region_bitmap);
2153 if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
2154 quorum_region = 1;
2155 clear_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
2156 spin_unlock(&o2hb_live_lock);
2157 printk(KERN_NOTICE "o2hb: Heartbeat %s on region %s (%s)\n",
2158 ((atomic_read(&reg->hr_steady_iterations) == 0) ?
2159 "stopped" : "start aborted"), config_item_name(item),
2160 reg->hr_dev_name);
2161 }
2162
2163 /*
2164 * If we're racing a dev_write(), we need to wake them. They will
2165 * check reg->hr_task
2166 */
2167 if (atomic_read(&reg->hr_steady_iterations) != 0) {
2168 reg->hr_aborted_start = 1;
2169 atomic_set(&reg->hr_steady_iterations, 0);
2170 wake_up(&o2hb_steady_queue);
2171 }
2172
2173 config_item_put(item);
2174
2175 if (!o2hb_global_heartbeat_active() || !quorum_region)
2176 return;
2177
2178 /*
2179 * If global heartbeat active and there are dependent users,
2180 * pin all regions if quorum region count <= CUT_OFF
2181 */
2182 spin_lock(&o2hb_live_lock);
2183
2184 if (!o2hb_dependent_users)
2185 goto unlock;
2186
2187 if (o2hb_pop_count(&o2hb_quorum_region_bitmap,
2188 O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF)
2189 o2hb_region_pin(NULL);
2190
2191 unlock:
2192 spin_unlock(&o2hb_live_lock);
2193 }
2194
2195 struct o2hb_heartbeat_group_attribute {
2196 struct configfs_attribute attr;
2197 ssize_t (*show)(struct o2hb_heartbeat_group *, char *);
2198 ssize_t (*store)(struct o2hb_heartbeat_group *, const char *, size_t);
2199 };
2200
2201 static ssize_t o2hb_heartbeat_group_show(struct config_item *item,
2202 struct configfs_attribute *attr,
2203 char *page)
2204 {
2205 struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item));
2206 struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr =
2207 container_of(attr, struct o2hb_heartbeat_group_attribute, attr);
2208 ssize_t ret = 0;
2209
2210 if (o2hb_heartbeat_group_attr->show)
2211 ret = o2hb_heartbeat_group_attr->show(reg, page);
2212 return ret;
2213 }
2214
2215 static ssize_t o2hb_heartbeat_group_store(struct config_item *item,
2216 struct configfs_attribute *attr,
2217 const char *page, size_t count)
2218 {
2219 struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item));
2220 struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr =
2221 container_of(attr, struct o2hb_heartbeat_group_attribute, attr);
2222 ssize_t ret = -EINVAL;
2223
2224 if (o2hb_heartbeat_group_attr->store)
2225 ret = o2hb_heartbeat_group_attr->store(reg, page, count);
2226 return ret;
2227 }
2228
2229 static ssize_t o2hb_heartbeat_group_threshold_show(struct o2hb_heartbeat_group *group,
2230 char *page)
2231 {
2232 return sprintf(page, "%u\n", o2hb_dead_threshold);
2233 }
2234
2235 static ssize_t o2hb_heartbeat_group_threshold_store(struct o2hb_heartbeat_group *group,
2236 const char *page,
2237 size_t count)
2238 {
2239 unsigned long tmp;
2240 char *p = (char *)page;
2241
2242 tmp = simple_strtoul(p, &p, 10);
2243 if (!p || (*p && (*p != '\n')))
2244 return -EINVAL;
2245
2246 /* this will validate ranges for us. */
2247 o2hb_dead_threshold_set((unsigned int) tmp);
2248
2249 return count;
2250 }
2251
2252 static
2253 ssize_t o2hb_heartbeat_group_mode_show(struct o2hb_heartbeat_group *group,
2254 char *page)
2255 {
2256 return sprintf(page, "%s\n",
2257 o2hb_heartbeat_mode_desc[o2hb_heartbeat_mode]);
2258 }
2259
2260 static
2261 ssize_t o2hb_heartbeat_group_mode_store(struct o2hb_heartbeat_group *group,
2262 const char *page, size_t count)
2263 {
2264 unsigned int i;
2265 int ret;
2266 size_t len;
2267
2268 len = (page[count - 1] == '\n') ? count - 1 : count;
2269 if (!len)
2270 return -EINVAL;
2271
2272 for (i = 0; i < O2HB_HEARTBEAT_NUM_MODES; ++i) {
2273 if (strnicmp(page, o2hb_heartbeat_mode_desc[i], len))
2274 continue;
2275
2276 ret = o2hb_global_hearbeat_mode_set(i);
2277 if (!ret)
2278 printk(KERN_NOTICE "o2hb: Heartbeat mode set to %s\n",
2279 o2hb_heartbeat_mode_desc[i]);
2280 return count;
2281 }
2282
2283 return -EINVAL;
2284
2285 }
2286
2287 static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_threshold = {
2288 .attr = { .ca_owner = THIS_MODULE,
2289 .ca_name = "dead_threshold",
2290 .ca_mode = S_IRUGO | S_IWUSR },
2291 .show = o2hb_heartbeat_group_threshold_show,
2292 .store = o2hb_heartbeat_group_threshold_store,
2293 };
2294
2295 static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_mode = {
2296 .attr = { .ca_owner = THIS_MODULE,
2297 .ca_name = "mode",
2298 .ca_mode = S_IRUGO | S_IWUSR },
2299 .show = o2hb_heartbeat_group_mode_show,
2300 .store = o2hb_heartbeat_group_mode_store,
2301 };
2302
2303 static struct configfs_attribute *o2hb_heartbeat_group_attrs[] = {
2304 &o2hb_heartbeat_group_attr_threshold.attr,
2305 &o2hb_heartbeat_group_attr_mode.attr,
2306 NULL,
2307 };
2308
2309 static struct configfs_item_operations o2hb_hearbeat_group_item_ops = {
2310 .show_attribute = o2hb_heartbeat_group_show,
2311 .store_attribute = o2hb_heartbeat_group_store,
2312 };
2313
2314 static struct configfs_group_operations o2hb_heartbeat_group_group_ops = {
2315 .make_item = o2hb_heartbeat_group_make_item,
2316 .drop_item = o2hb_heartbeat_group_drop_item,
2317 };
2318
2319 static struct config_item_type o2hb_heartbeat_group_type = {
2320 .ct_group_ops = &o2hb_heartbeat_group_group_ops,
2321 .ct_item_ops = &o2hb_hearbeat_group_item_ops,
2322 .ct_attrs = o2hb_heartbeat_group_attrs,
2323 .ct_owner = THIS_MODULE,
2324 };
2325
2326 /* this is just here to avoid touching group in heartbeat.h which the
2327 * entire damn world #includes */
2328 struct config_group *o2hb_alloc_hb_set(void)
2329 {
2330 struct o2hb_heartbeat_group *hs = NULL;
2331 struct config_group *ret = NULL;
2332
2333 hs = kzalloc(sizeof(struct o2hb_heartbeat_group), GFP_KERNEL);
2334 if (hs == NULL)
2335 goto out;
2336
2337 config_group_init_type_name(&hs->hs_group, "heartbeat",
2338 &o2hb_heartbeat_group_type);
2339
2340 ret = &hs->hs_group;
2341 out:
2342 if (ret == NULL)
2343 kfree(hs);
2344 return ret;
2345 }
2346
2347 void o2hb_free_hb_set(struct config_group *group)
2348 {
2349 struct o2hb_heartbeat_group *hs = to_o2hb_heartbeat_group(group);
2350 kfree(hs);
2351 }
2352
2353 /* hb callback registration and issuing */
2354
2355 static struct o2hb_callback *hbcall_from_type(enum o2hb_callback_type type)
2356 {
2357 if (type == O2HB_NUM_CB)
2358 return ERR_PTR(-EINVAL);
2359
2360 return &o2hb_callbacks[type];
2361 }
2362
2363 void o2hb_setup_callback(struct o2hb_callback_func *hc,
2364 enum o2hb_callback_type type,
2365 o2hb_cb_func *func,
2366 void *data,
2367 int priority)
2368 {
2369 INIT_LIST_HEAD(&hc->hc_item);
2370 hc->hc_func = func;
2371 hc->hc_data = data;
2372 hc->hc_priority = priority;
2373 hc->hc_type = type;
2374 hc->hc_magic = O2HB_CB_MAGIC;
2375 }
2376 EXPORT_SYMBOL_GPL(o2hb_setup_callback);
2377
2378 /*
2379 * In local heartbeat mode, region_uuid passed matches the dlm domain name.
2380 * In global heartbeat mode, region_uuid passed is NULL.
2381 *
2382 * In local, we only pin the matching region. In global we pin all the active
2383 * regions.
2384 */
2385 static int o2hb_region_pin(const char *region_uuid)
2386 {
2387 int ret = 0, found = 0;
2388 struct o2hb_region *reg;
2389 char *uuid;
2390
2391 assert_spin_locked(&o2hb_live_lock);
2392
2393 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) {
2394 uuid = config_item_name(&reg->hr_item);
2395
2396 /* local heartbeat */
2397 if (region_uuid) {
2398 if (strcmp(region_uuid, uuid))
2399 continue;
2400 found = 1;
2401 }
2402
2403 if (reg->hr_item_pinned || reg->hr_item_dropped)
2404 goto skip_pin;
2405
2406 /* Ignore ENOENT only for local hb (userdlm domain) */
2407 ret = o2nm_depend_item(&reg->hr_item);
2408 if (!ret) {
2409 mlog(ML_CLUSTER, "Pin region %s\n", uuid);
2410 reg->hr_item_pinned = 1;
2411 } else {
2412 if (ret == -ENOENT && found)
2413 ret = 0;
2414 else {
2415 mlog(ML_ERROR, "Pin region %s fails with %d\n",
2416 uuid, ret);
2417 break;
2418 }
2419 }
2420 skip_pin:
2421 if (found)
2422 break;
2423 }
2424
2425 return ret;
2426 }
2427
2428 /*
2429 * In local heartbeat mode, region_uuid passed matches the dlm domain name.
2430 * In global heartbeat mode, region_uuid passed is NULL.
2431 *
2432 * In local, we only unpin the matching region. In global we unpin all the
2433 * active regions.
2434 */
2435 static void o2hb_region_unpin(const char *region_uuid)
2436 {
2437 struct o2hb_region *reg;
2438 char *uuid;
2439 int found = 0;
2440
2441 assert_spin_locked(&o2hb_live_lock);
2442
2443 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) {
2444 uuid = config_item_name(&reg->hr_item);
2445 if (region_uuid) {
2446 if (strcmp(region_uuid, uuid))
2447 continue;
2448 found = 1;
2449 }
2450
2451 if (reg->hr_item_pinned) {
2452 mlog(ML_CLUSTER, "Unpin region %s\n", uuid);
2453 o2nm_undepend_item(&reg->hr_item);
2454 reg->hr_item_pinned = 0;
2455 }
2456 if (found)
2457 break;
2458 }
2459 }
2460
2461 static int o2hb_region_inc_user(const char *region_uuid)
2462 {
2463 int ret = 0;
2464
2465 spin_lock(&o2hb_live_lock);
2466
2467 /* local heartbeat */
2468 if (!o2hb_global_heartbeat_active()) {
2469 ret = o2hb_region_pin(region_uuid);
2470 goto unlock;
2471 }
2472
2473 /*
2474 * if global heartbeat active and this is the first dependent user,
2475 * pin all regions if quorum region count <= CUT_OFF
2476 */
2477 o2hb_dependent_users++;
2478 if (o2hb_dependent_users > 1)
2479 goto unlock;
2480
2481 if (o2hb_pop_count(&o2hb_quorum_region_bitmap,
2482 O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF)
2483 ret = o2hb_region_pin(NULL);
2484
2485 unlock:
2486 spin_unlock(&o2hb_live_lock);
2487 return ret;
2488 }
2489
2490 void o2hb_region_dec_user(const char *region_uuid)
2491 {
2492 spin_lock(&o2hb_live_lock);
2493
2494 /* local heartbeat */
2495 if (!o2hb_global_heartbeat_active()) {
2496 o2hb_region_unpin(region_uuid);
2497 goto unlock;
2498 }
2499
2500 /*
2501 * if global heartbeat active and there are no dependent users,
2502 * unpin all quorum regions
2503 */
2504 o2hb_dependent_users--;
2505 if (!o2hb_dependent_users)
2506 o2hb_region_unpin(NULL);
2507
2508 unlock:
2509 spin_unlock(&o2hb_live_lock);
2510 }
2511
2512 int o2hb_register_callback(const char *region_uuid,
2513 struct o2hb_callback_func *hc)
2514 {
2515 struct o2hb_callback_func *tmp;
2516 struct list_head *iter;
2517 struct o2hb_callback *hbcall;
2518 int ret;
2519
2520 BUG_ON(hc->hc_magic != O2HB_CB_MAGIC);
2521 BUG_ON(!list_empty(&hc->hc_item));
2522
2523 hbcall = hbcall_from_type(hc->hc_type);
2524 if (IS_ERR(hbcall)) {
2525 ret = PTR_ERR(hbcall);
2526 goto out;
2527 }
2528
2529 if (region_uuid) {
2530 ret = o2hb_region_inc_user(region_uuid);
2531 if (ret) {
2532 mlog_errno(ret);
2533 goto out;
2534 }
2535 }
2536
2537 down_write(&o2hb_callback_sem);
2538
2539 list_for_each(iter, &hbcall->list) {
2540 tmp = list_entry(iter, struct o2hb_callback_func, hc_item);
2541 if (hc->hc_priority < tmp->hc_priority) {
2542 list_add_tail(&hc->hc_item, iter);
2543 break;
2544 }
2545 }
2546 if (list_empty(&hc->hc_item))
2547 list_add_tail(&hc->hc_item, &hbcall->list);
2548
2549 up_write(&o2hb_callback_sem);
2550 ret = 0;
2551 out:
2552 mlog(ML_CLUSTER, "returning %d on behalf of %p for funcs %p\n",
2553 ret, __builtin_return_address(0), hc);
2554 return ret;
2555 }
2556 EXPORT_SYMBOL_GPL(o2hb_register_callback);
2557
2558 void o2hb_unregister_callback(const char *region_uuid,
2559 struct o2hb_callback_func *hc)
2560 {
2561 BUG_ON(hc->hc_magic != O2HB_CB_MAGIC);
2562
2563 mlog(ML_CLUSTER, "on behalf of %p for funcs %p\n",
2564 __builtin_return_address(0), hc);
2565
2566 /* XXX Can this happen _with_ a region reference? */
2567 if (list_empty(&hc->hc_item))
2568 return;
2569
2570 if (region_uuid)
2571 o2hb_region_dec_user(region_uuid);
2572
2573 down_write(&o2hb_callback_sem);
2574
2575 list_del_init(&hc->hc_item);
2576
2577 up_write(&o2hb_callback_sem);
2578 }
2579 EXPORT_SYMBOL_GPL(o2hb_unregister_callback);
2580
2581 int o2hb_check_node_heartbeating(u8 node_num)
2582 {
2583 unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
2584
2585 o2hb_fill_node_map(testing_map, sizeof(testing_map));
2586 if (!test_bit(node_num, testing_map)) {
2587 mlog(ML_HEARTBEAT,
2588 "node (%u) does not have heartbeating enabled.\n",
2589 node_num);
2590 return 0;
2591 }
2592
2593 return 1;
2594 }
2595 EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating);
2596
2597 int o2hb_check_node_heartbeating_from_callback(u8 node_num)
2598 {
2599 unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
2600
2601 o2hb_fill_node_map_from_callback(testing_map, sizeof(testing_map));
2602 if (!test_bit(node_num, testing_map)) {
2603 mlog(ML_HEARTBEAT,
2604 "node (%u) does not have heartbeating enabled.\n",
2605 node_num);
2606 return 0;
2607 }
2608
2609 return 1;
2610 }
2611 EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating_from_callback);
2612
2613 /* Makes sure our local node is configured with a node number, and is
2614 * heartbeating. */
2615 int o2hb_check_local_node_heartbeating(void)
2616 {
2617 u8 node_num;
2618
2619 /* if this node was set then we have networking */
2620 node_num = o2nm_this_node();
2621 if (node_num == O2NM_MAX_NODES) {
2622 mlog(ML_HEARTBEAT, "this node has not been configured.\n");
2623 return 0;
2624 }
2625
2626 return o2hb_check_node_heartbeating(node_num);
2627 }
2628 EXPORT_SYMBOL_GPL(o2hb_check_local_node_heartbeating);
2629
2630 /*
2631 * this is just a hack until we get the plumbing which flips file systems
2632 * read only and drops the hb ref instead of killing the node dead.
2633 */
2634 void o2hb_stop_all_regions(void)
2635 {
2636 struct o2hb_region *reg;
2637
2638 mlog(ML_ERROR, "stopping heartbeat on all active regions.\n");
2639
2640 spin_lock(&o2hb_live_lock);
2641
2642 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item)
2643 reg->hr_unclean_stop = 1;
2644
2645 spin_unlock(&o2hb_live_lock);
2646 }
2647 EXPORT_SYMBOL_GPL(o2hb_stop_all_regions);
2648
2649 int o2hb_get_all_regions(char *region_uuids, u8 max_regions)
2650 {
2651 struct o2hb_region *reg;
2652 int numregs = 0;
2653 char *p;
2654
2655 spin_lock(&o2hb_live_lock);
2656
2657 p = region_uuids;
2658 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) {
2659 mlog(0, "Region: %s\n", config_item_name(&reg->hr_item));
2660 if (numregs < max_regions) {
2661 memcpy(p, config_item_name(&reg->hr_item),
2662 O2HB_MAX_REGION_NAME_LEN);
2663 p += O2HB_MAX_REGION_NAME_LEN;
2664 }
2665 numregs++;
2666 }
2667
2668 spin_unlock(&o2hb_live_lock);
2669
2670 return numregs;
2671 }
2672 EXPORT_SYMBOL_GPL(o2hb_get_all_regions);
2673
2674 int o2hb_global_heartbeat_active(void)
2675 {
2676 return (o2hb_heartbeat_mode == O2HB_HEARTBEAT_GLOBAL);
2677 }
2678 EXPORT_SYMBOL(o2hb_global_heartbeat_active);