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 #include <linux/bitmap.h> 39 40 #include "heartbeat.h" 41 #include "tcp.h" 42 #include "nodemanager.h" 43 #include "quorum.h" 44 45 #include "masklog.h" 46 47 48 /* 49 * The first heartbeat pass had one global thread that would serialize all hb 50 * callback calls. This global serializing sem should only be removed once 51 * we've made sure that all callees can deal with being called concurrently 52 * from multiple hb region threads. 53 */ 54 static DECLARE_RWSEM(o2hb_callback_sem); 55 56 /* 57 * multiple hb threads are watching multiple regions. A node is live 58 * whenever any of the threads sees activity from the node in its region. 59 */ 60 static DEFINE_SPINLOCK(o2hb_live_lock); 61 static struct list_head o2hb_live_slots[O2NM_MAX_NODES]; 62 static unsigned long o2hb_live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)]; 63 static LIST_HEAD(o2hb_node_events); 64 static DECLARE_WAIT_QUEUE_HEAD(o2hb_steady_queue); 65 66 /* 67 * In global heartbeat, we maintain a series of region bitmaps. 68 * - o2hb_region_bitmap allows us to limit the region number to max region. 69 * - o2hb_live_region_bitmap tracks live regions (seen steady iterations). 70 * - o2hb_quorum_region_bitmap tracks live regions that have seen all nodes 71 * heartbeat on it. 72 * - o2hb_failed_region_bitmap tracks the regions that have seen io timeouts. 73 */ 74 static unsigned long o2hb_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)]; 75 static unsigned long o2hb_live_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)]; 76 static unsigned long o2hb_quorum_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)]; 77 static unsigned long o2hb_failed_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)]; 78 79 #define O2HB_DB_TYPE_LIVENODES 0 80 #define O2HB_DB_TYPE_LIVEREGIONS 1 81 #define O2HB_DB_TYPE_QUORUMREGIONS 2 82 #define O2HB_DB_TYPE_FAILEDREGIONS 3 83 #define O2HB_DB_TYPE_REGION_LIVENODES 4 84 #define O2HB_DB_TYPE_REGION_NUMBER 5 85 #define O2HB_DB_TYPE_REGION_ELAPSED_TIME 6 86 #define O2HB_DB_TYPE_REGION_PINNED 7 87 struct o2hb_debug_buf { 88 int db_type; 89 int db_size; 90 int db_len; 91 void *db_data; 92 }; 93 94 static struct o2hb_debug_buf *o2hb_db_livenodes; 95 static struct o2hb_debug_buf *o2hb_db_liveregions; 96 static struct o2hb_debug_buf *o2hb_db_quorumregions; 97 static struct o2hb_debug_buf *o2hb_db_failedregions; 98 99 #define O2HB_DEBUG_DIR "o2hb" 100 #define O2HB_DEBUG_LIVENODES "livenodes" 101 #define O2HB_DEBUG_LIVEREGIONS "live_regions" 102 #define O2HB_DEBUG_QUORUMREGIONS "quorum_regions" 103 #define O2HB_DEBUG_FAILEDREGIONS "failed_regions" 104 #define O2HB_DEBUG_REGION_NUMBER "num" 105 #define O2HB_DEBUG_REGION_ELAPSED_TIME "elapsed_time_in_ms" 106 #define O2HB_DEBUG_REGION_PINNED "pinned" 107 108 static struct dentry *o2hb_debug_dir; 109 static struct dentry *o2hb_debug_livenodes; 110 static struct dentry *o2hb_debug_liveregions; 111 static struct dentry *o2hb_debug_quorumregions; 112 static struct dentry *o2hb_debug_failedregions; 113 114 static LIST_HEAD(o2hb_all_regions); 115 116 static struct o2hb_callback { 117 struct list_head list; 118 } o2hb_callbacks[O2HB_NUM_CB]; 119 120 static struct o2hb_callback *hbcall_from_type(enum o2hb_callback_type type); 121 122 #define O2HB_DEFAULT_BLOCK_BITS 9 123 124 enum o2hb_heartbeat_modes { 125 O2HB_HEARTBEAT_LOCAL = 0, 126 O2HB_HEARTBEAT_GLOBAL, 127 O2HB_HEARTBEAT_NUM_MODES, 128 }; 129 130 char *o2hb_heartbeat_mode_desc[O2HB_HEARTBEAT_NUM_MODES] = { 131 "local", /* O2HB_HEARTBEAT_LOCAL */ 132 "global", /* O2HB_HEARTBEAT_GLOBAL */ 133 }; 134 135 unsigned int o2hb_dead_threshold = O2HB_DEFAULT_DEAD_THRESHOLD; 136 unsigned int o2hb_heartbeat_mode = O2HB_HEARTBEAT_LOCAL; 137 138 /* 139 * o2hb_dependent_users tracks the number of registered callbacks that depend 140 * on heartbeat. o2net and o2dlm are two entities that register this callback. 141 * However only o2dlm depends on the heartbeat. It does not want the heartbeat 142 * to stop while a dlm domain is still active. 143 */ 144 unsigned int o2hb_dependent_users; 145 146 /* 147 * In global heartbeat mode, all regions are pinned if there are one or more 148 * dependent users and the quorum region count is <= O2HB_PIN_CUT_OFF. All 149 * regions are unpinned if the region count exceeds the cut off or the number 150 * of dependent users falls to zero. 151 */ 152 #define O2HB_PIN_CUT_OFF 3 153 154 /* 155 * In local heartbeat mode, we assume the dlm domain name to be the same as 156 * region uuid. This is true for domains created for the file system but not 157 * necessarily true for userdlm domains. This is a known limitation. 158 * 159 * In global heartbeat mode, we pin/unpin all o2hb regions. This solution 160 * works for both file system and userdlm domains. 161 */ 162 static int o2hb_region_pin(const char *region_uuid); 163 static void o2hb_region_unpin(const char *region_uuid); 164 165 /* Only sets a new threshold if there are no active regions. 166 * 167 * No locking or otherwise interesting code is required for reading 168 * o2hb_dead_threshold as it can't change once regions are active and 169 * it's not interesting to anyone until then anyway. */ 170 static void o2hb_dead_threshold_set(unsigned int threshold) 171 { 172 if (threshold > O2HB_MIN_DEAD_THRESHOLD) { 173 spin_lock(&o2hb_live_lock); 174 if (list_empty(&o2hb_all_regions)) 175 o2hb_dead_threshold = threshold; 176 spin_unlock(&o2hb_live_lock); 177 } 178 } 179 180 static int o2hb_global_heartbeat_mode_set(unsigned int hb_mode) 181 { 182 int ret = -1; 183 184 if (hb_mode < O2HB_HEARTBEAT_NUM_MODES) { 185 spin_lock(&o2hb_live_lock); 186 if (list_empty(&o2hb_all_regions)) { 187 o2hb_heartbeat_mode = hb_mode; 188 ret = 0; 189 } 190 spin_unlock(&o2hb_live_lock); 191 } 192 193 return ret; 194 } 195 196 struct o2hb_node_event { 197 struct list_head hn_item; 198 enum o2hb_callback_type hn_event_type; 199 struct o2nm_node *hn_node; 200 int hn_node_num; 201 }; 202 203 struct o2hb_disk_slot { 204 struct o2hb_disk_heartbeat_block *ds_raw_block; 205 u8 ds_node_num; 206 u64 ds_last_time; 207 u64 ds_last_generation; 208 u16 ds_equal_samples; 209 u16 ds_changed_samples; 210 struct list_head ds_live_item; 211 }; 212 213 /* each thread owns a region.. when we're asked to tear down the region 214 * we ask the thread to stop, who cleans up the region */ 215 struct o2hb_region { 216 struct config_item hr_item; 217 218 struct list_head hr_all_item; 219 unsigned hr_unclean_stop:1, 220 hr_aborted_start:1, 221 hr_item_pinned:1, 222 hr_item_dropped:1; 223 224 /* protected by the hr_callback_sem */ 225 struct task_struct *hr_task; 226 227 unsigned int hr_blocks; 228 unsigned long long hr_start_block; 229 230 unsigned int hr_block_bits; 231 unsigned int hr_block_bytes; 232 233 unsigned int hr_slots_per_page; 234 unsigned int hr_num_pages; 235 236 struct page **hr_slot_data; 237 struct block_device *hr_bdev; 238 struct o2hb_disk_slot *hr_slots; 239 240 /* live node map of this region */ 241 unsigned long hr_live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)]; 242 unsigned int hr_region_num; 243 244 struct dentry *hr_debug_dir; 245 struct dentry *hr_debug_livenodes; 246 struct dentry *hr_debug_regnum; 247 struct dentry *hr_debug_elapsed_time; 248 struct dentry *hr_debug_pinned; 249 struct o2hb_debug_buf *hr_db_livenodes; 250 struct o2hb_debug_buf *hr_db_regnum; 251 struct o2hb_debug_buf *hr_db_elapsed_time; 252 struct o2hb_debug_buf *hr_db_pinned; 253 254 /* let the person setting up hb wait for it to return until it 255 * has reached a 'steady' state. This will be fixed when we have 256 * a more complete api that doesn't lead to this sort of fragility. */ 257 atomic_t hr_steady_iterations; 258 259 /* terminate o2hb thread if it does not reach steady state 260 * (hr_steady_iterations == 0) within hr_unsteady_iterations */ 261 atomic_t hr_unsteady_iterations; 262 263 char hr_dev_name[BDEVNAME_SIZE]; 264 265 unsigned int hr_timeout_ms; 266 267 /* randomized as the region goes up and down so that a node 268 * recognizes a node going up and down in one iteration */ 269 u64 hr_generation; 270 271 struct delayed_work hr_write_timeout_work; 272 unsigned long hr_last_timeout_start; 273 274 /* Used during o2hb_check_slot to hold a copy of the block 275 * being checked because we temporarily have to zero out the 276 * crc field. */ 277 struct o2hb_disk_heartbeat_block *hr_tmp_block; 278 }; 279 280 struct o2hb_bio_wait_ctxt { 281 atomic_t wc_num_reqs; 282 struct completion wc_io_complete; 283 int wc_error; 284 }; 285 286 static void o2hb_write_timeout(struct work_struct *work) 287 { 288 int failed, quorum; 289 unsigned long flags; 290 struct o2hb_region *reg = 291 container_of(work, struct o2hb_region, 292 hr_write_timeout_work.work); 293 294 mlog(ML_ERROR, "Heartbeat write timeout to device %s after %u " 295 "milliseconds\n", reg->hr_dev_name, 296 jiffies_to_msecs(jiffies - reg->hr_last_timeout_start)); 297 298 if (o2hb_global_heartbeat_active()) { 299 spin_lock_irqsave(&o2hb_live_lock, flags); 300 if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap)) 301 set_bit(reg->hr_region_num, o2hb_failed_region_bitmap); 302 failed = bitmap_weight(o2hb_failed_region_bitmap, 303 O2NM_MAX_REGIONS); 304 quorum = bitmap_weight(o2hb_quorum_region_bitmap, 305 O2NM_MAX_REGIONS); 306 spin_unlock_irqrestore(&o2hb_live_lock, flags); 307 308 mlog(ML_HEARTBEAT, "Number of regions %d, failed regions %d\n", 309 quorum, failed); 310 311 /* 312 * Fence if the number of failed regions >= half the number 313 * of quorum regions 314 */ 315 if ((failed << 1) < quorum) 316 return; 317 } 318 319 o2quo_disk_timeout(); 320 } 321 322 static void o2hb_arm_write_timeout(struct o2hb_region *reg) 323 { 324 /* Arm writeout only after thread reaches steady state */ 325 if (atomic_read(®->hr_steady_iterations) != 0) 326 return; 327 328 mlog(ML_HEARTBEAT, "Queue write timeout for %u ms\n", 329 O2HB_MAX_WRITE_TIMEOUT_MS); 330 331 if (o2hb_global_heartbeat_active()) { 332 spin_lock(&o2hb_live_lock); 333 clear_bit(reg->hr_region_num, o2hb_failed_region_bitmap); 334 spin_unlock(&o2hb_live_lock); 335 } 336 cancel_delayed_work(®->hr_write_timeout_work); 337 reg->hr_last_timeout_start = jiffies; 338 schedule_delayed_work(®->hr_write_timeout_work, 339 msecs_to_jiffies(O2HB_MAX_WRITE_TIMEOUT_MS)); 340 } 341 342 static void o2hb_disarm_write_timeout(struct o2hb_region *reg) 343 { 344 cancel_delayed_work_sync(®->hr_write_timeout_work); 345 } 346 347 static inline void o2hb_bio_wait_init(struct o2hb_bio_wait_ctxt *wc) 348 { 349 atomic_set(&wc->wc_num_reqs, 1); 350 init_completion(&wc->wc_io_complete); 351 wc->wc_error = 0; 352 } 353 354 /* Used in error paths too */ 355 static inline void o2hb_bio_wait_dec(struct o2hb_bio_wait_ctxt *wc, 356 unsigned int num) 357 { 358 /* sadly atomic_sub_and_test() isn't available on all platforms. The 359 * good news is that the fast path only completes one at a time */ 360 while(num--) { 361 if (atomic_dec_and_test(&wc->wc_num_reqs)) { 362 BUG_ON(num > 0); 363 complete(&wc->wc_io_complete); 364 } 365 } 366 } 367 368 static void o2hb_wait_on_io(struct o2hb_region *reg, 369 struct o2hb_bio_wait_ctxt *wc) 370 { 371 o2hb_bio_wait_dec(wc, 1); 372 wait_for_completion(&wc->wc_io_complete); 373 } 374 375 static void o2hb_bio_end_io(struct bio *bio, 376 int error) 377 { 378 struct o2hb_bio_wait_ctxt *wc = bio->bi_private; 379 380 if (error) { 381 mlog(ML_ERROR, "IO Error %d\n", error); 382 wc->wc_error = error; 383 } 384 385 o2hb_bio_wait_dec(wc, 1); 386 bio_put(bio); 387 } 388 389 /* Setup a Bio to cover I/O against num_slots slots starting at 390 * start_slot. */ 391 static struct bio *o2hb_setup_one_bio(struct o2hb_region *reg, 392 struct o2hb_bio_wait_ctxt *wc, 393 unsigned int *current_slot, 394 unsigned int max_slots) 395 { 396 int len, current_page; 397 unsigned int vec_len, vec_start; 398 unsigned int bits = reg->hr_block_bits; 399 unsigned int spp = reg->hr_slots_per_page; 400 unsigned int cs = *current_slot; 401 struct bio *bio; 402 struct page *page; 403 404 /* Testing has shown this allocation to take long enough under 405 * GFP_KERNEL that the local node can get fenced. It would be 406 * nicest if we could pre-allocate these bios and avoid this 407 * all together. */ 408 bio = bio_alloc(GFP_ATOMIC, 16); 409 if (!bio) { 410 mlog(ML_ERROR, "Could not alloc slots BIO!\n"); 411 bio = ERR_PTR(-ENOMEM); 412 goto bail; 413 } 414 415 /* Must put everything in 512 byte sectors for the bio... */ 416 bio->bi_iter.bi_sector = (reg->hr_start_block + cs) << (bits - 9); 417 bio->bi_bdev = reg->hr_bdev; 418 bio->bi_private = wc; 419 bio->bi_end_io = o2hb_bio_end_io; 420 421 vec_start = (cs << bits) % PAGE_CACHE_SIZE; 422 while(cs < max_slots) { 423 current_page = cs / spp; 424 page = reg->hr_slot_data[current_page]; 425 426 vec_len = min(PAGE_CACHE_SIZE - vec_start, 427 (max_slots-cs) * (PAGE_CACHE_SIZE/spp) ); 428 429 mlog(ML_HB_BIO, "page %d, vec_len = %u, vec_start = %u\n", 430 current_page, vec_len, vec_start); 431 432 len = bio_add_page(bio, page, vec_len, vec_start); 433 if (len != vec_len) break; 434 435 cs += vec_len / (PAGE_CACHE_SIZE/spp); 436 vec_start = 0; 437 } 438 439 bail: 440 *current_slot = cs; 441 return bio; 442 } 443 444 static int o2hb_read_slots(struct o2hb_region *reg, 445 unsigned int max_slots) 446 { 447 unsigned int current_slot=0; 448 int status; 449 struct o2hb_bio_wait_ctxt wc; 450 struct bio *bio; 451 452 o2hb_bio_wait_init(&wc); 453 454 while(current_slot < max_slots) { 455 bio = o2hb_setup_one_bio(reg, &wc, ¤t_slot, max_slots); 456 if (IS_ERR(bio)) { 457 status = PTR_ERR(bio); 458 mlog_errno(status); 459 goto bail_and_wait; 460 } 461 462 atomic_inc(&wc.wc_num_reqs); 463 submit_bio(READ, bio); 464 } 465 466 status = 0; 467 468 bail_and_wait: 469 o2hb_wait_on_io(reg, &wc); 470 if (wc.wc_error && !status) 471 status = wc.wc_error; 472 473 return status; 474 } 475 476 static int o2hb_issue_node_write(struct o2hb_region *reg, 477 struct o2hb_bio_wait_ctxt *write_wc) 478 { 479 int status; 480 unsigned int slot; 481 struct bio *bio; 482 483 o2hb_bio_wait_init(write_wc); 484 485 slot = o2nm_this_node(); 486 487 bio = o2hb_setup_one_bio(reg, write_wc, &slot, slot+1); 488 if (IS_ERR(bio)) { 489 status = PTR_ERR(bio); 490 mlog_errno(status); 491 goto bail; 492 } 493 494 atomic_inc(&write_wc->wc_num_reqs); 495 submit_bio(WRITE_SYNC, bio); 496 497 status = 0; 498 bail: 499 return status; 500 } 501 502 static u32 o2hb_compute_block_crc_le(struct o2hb_region *reg, 503 struct o2hb_disk_heartbeat_block *hb_block) 504 { 505 __le32 old_cksum; 506 u32 ret; 507 508 /* We want to compute the block crc with a 0 value in the 509 * hb_cksum field. Save it off here and replace after the 510 * crc. */ 511 old_cksum = hb_block->hb_cksum; 512 hb_block->hb_cksum = 0; 513 514 ret = crc32_le(0, (unsigned char *) hb_block, reg->hr_block_bytes); 515 516 hb_block->hb_cksum = old_cksum; 517 518 return ret; 519 } 520 521 static void o2hb_dump_slot(struct o2hb_disk_heartbeat_block *hb_block) 522 { 523 mlog(ML_ERROR, "Dump slot information: seq = 0x%llx, node = %u, " 524 "cksum = 0x%x, generation 0x%llx\n", 525 (long long)le64_to_cpu(hb_block->hb_seq), 526 hb_block->hb_node, le32_to_cpu(hb_block->hb_cksum), 527 (long long)le64_to_cpu(hb_block->hb_generation)); 528 } 529 530 static int o2hb_verify_crc(struct o2hb_region *reg, 531 struct o2hb_disk_heartbeat_block *hb_block) 532 { 533 u32 read, computed; 534 535 read = le32_to_cpu(hb_block->hb_cksum); 536 computed = o2hb_compute_block_crc_le(reg, hb_block); 537 538 return read == computed; 539 } 540 541 /* 542 * Compare the slot data with what we wrote in the last iteration. 543 * If the match fails, print an appropriate error message. This is to 544 * detect errors like... another node hearting on the same slot, 545 * flaky device that is losing writes, etc. 546 * Returns 1 if check succeeds, 0 otherwise. 547 */ 548 static int o2hb_check_own_slot(struct o2hb_region *reg) 549 { 550 struct o2hb_disk_slot *slot; 551 struct o2hb_disk_heartbeat_block *hb_block; 552 char *errstr; 553 554 slot = ®->hr_slots[o2nm_this_node()]; 555 /* Don't check on our 1st timestamp */ 556 if (!slot->ds_last_time) 557 return 0; 558 559 hb_block = slot->ds_raw_block; 560 if (le64_to_cpu(hb_block->hb_seq) == slot->ds_last_time && 561 le64_to_cpu(hb_block->hb_generation) == slot->ds_last_generation && 562 hb_block->hb_node == slot->ds_node_num) 563 return 1; 564 565 #define ERRSTR1 "Another node is heartbeating on device" 566 #define ERRSTR2 "Heartbeat generation mismatch on device" 567 #define ERRSTR3 "Heartbeat sequence mismatch on device" 568 569 if (hb_block->hb_node != slot->ds_node_num) 570 errstr = ERRSTR1; 571 else if (le64_to_cpu(hb_block->hb_generation) != 572 slot->ds_last_generation) 573 errstr = ERRSTR2; 574 else 575 errstr = ERRSTR3; 576 577 mlog(ML_ERROR, "%s (%s): expected(%u:0x%llx, 0x%llx), " 578 "ondisk(%u:0x%llx, 0x%llx)\n", errstr, reg->hr_dev_name, 579 slot->ds_node_num, (unsigned long long)slot->ds_last_generation, 580 (unsigned long long)slot->ds_last_time, hb_block->hb_node, 581 (unsigned long long)le64_to_cpu(hb_block->hb_generation), 582 (unsigned long long)le64_to_cpu(hb_block->hb_seq)); 583 584 return 0; 585 } 586 587 static inline void o2hb_prepare_block(struct o2hb_region *reg, 588 u64 generation) 589 { 590 int node_num; 591 u64 cputime; 592 struct o2hb_disk_slot *slot; 593 struct o2hb_disk_heartbeat_block *hb_block; 594 595 node_num = o2nm_this_node(); 596 slot = ®->hr_slots[node_num]; 597 598 hb_block = (struct o2hb_disk_heartbeat_block *)slot->ds_raw_block; 599 memset(hb_block, 0, reg->hr_block_bytes); 600 /* TODO: time stuff */ 601 cputime = CURRENT_TIME.tv_sec; 602 if (!cputime) 603 cputime = 1; 604 605 hb_block->hb_seq = cpu_to_le64(cputime); 606 hb_block->hb_node = node_num; 607 hb_block->hb_generation = cpu_to_le64(generation); 608 hb_block->hb_dead_ms = cpu_to_le32(o2hb_dead_threshold * O2HB_REGION_TIMEOUT_MS); 609 610 /* This step must always happen last! */ 611 hb_block->hb_cksum = cpu_to_le32(o2hb_compute_block_crc_le(reg, 612 hb_block)); 613 614 mlog(ML_HB_BIO, "our node generation = 0x%llx, cksum = 0x%x\n", 615 (long long)generation, 616 le32_to_cpu(hb_block->hb_cksum)); 617 } 618 619 static void o2hb_fire_callbacks(struct o2hb_callback *hbcall, 620 struct o2nm_node *node, 621 int idx) 622 { 623 struct o2hb_callback_func *f; 624 625 list_for_each_entry(f, &hbcall->list, hc_item) { 626 mlog(ML_HEARTBEAT, "calling funcs %p\n", f); 627 (f->hc_func)(node, idx, f->hc_data); 628 } 629 } 630 631 /* Will run the list in order until we process the passed event */ 632 static void o2hb_run_event_list(struct o2hb_node_event *queued_event) 633 { 634 struct o2hb_callback *hbcall; 635 struct o2hb_node_event *event; 636 637 /* Holding callback sem assures we don't alter the callback 638 * lists when doing this, and serializes ourselves with other 639 * processes wanting callbacks. */ 640 down_write(&o2hb_callback_sem); 641 642 spin_lock(&o2hb_live_lock); 643 while (!list_empty(&o2hb_node_events) 644 && !list_empty(&queued_event->hn_item)) { 645 event = list_entry(o2hb_node_events.next, 646 struct o2hb_node_event, 647 hn_item); 648 list_del_init(&event->hn_item); 649 spin_unlock(&o2hb_live_lock); 650 651 mlog(ML_HEARTBEAT, "Node %s event for %d\n", 652 event->hn_event_type == O2HB_NODE_UP_CB ? "UP" : "DOWN", 653 event->hn_node_num); 654 655 hbcall = hbcall_from_type(event->hn_event_type); 656 657 /* We should *never* have gotten on to the list with a 658 * bad type... This isn't something that we should try 659 * to recover from. */ 660 BUG_ON(IS_ERR(hbcall)); 661 662 o2hb_fire_callbacks(hbcall, event->hn_node, event->hn_node_num); 663 664 spin_lock(&o2hb_live_lock); 665 } 666 spin_unlock(&o2hb_live_lock); 667 668 up_write(&o2hb_callback_sem); 669 } 670 671 static void o2hb_queue_node_event(struct o2hb_node_event *event, 672 enum o2hb_callback_type type, 673 struct o2nm_node *node, 674 int node_num) 675 { 676 assert_spin_locked(&o2hb_live_lock); 677 678 BUG_ON((!node) && (type != O2HB_NODE_DOWN_CB)); 679 680 event->hn_event_type = type; 681 event->hn_node = node; 682 event->hn_node_num = node_num; 683 684 mlog(ML_HEARTBEAT, "Queue node %s event for node %d\n", 685 type == O2HB_NODE_UP_CB ? "UP" : "DOWN", node_num); 686 687 list_add_tail(&event->hn_item, &o2hb_node_events); 688 } 689 690 static void o2hb_shutdown_slot(struct o2hb_disk_slot *slot) 691 { 692 struct o2hb_node_event event = 693 { .hn_item = LIST_HEAD_INIT(event.hn_item), }; 694 struct o2nm_node *node; 695 int queued = 0; 696 697 node = o2nm_get_node_by_num(slot->ds_node_num); 698 if (!node) 699 return; 700 701 spin_lock(&o2hb_live_lock); 702 if (!list_empty(&slot->ds_live_item)) { 703 mlog(ML_HEARTBEAT, "Shutdown, node %d leaves region\n", 704 slot->ds_node_num); 705 706 list_del_init(&slot->ds_live_item); 707 708 if (list_empty(&o2hb_live_slots[slot->ds_node_num])) { 709 clear_bit(slot->ds_node_num, o2hb_live_node_bitmap); 710 711 o2hb_queue_node_event(&event, O2HB_NODE_DOWN_CB, node, 712 slot->ds_node_num); 713 queued = 1; 714 } 715 } 716 spin_unlock(&o2hb_live_lock); 717 718 if (queued) 719 o2hb_run_event_list(&event); 720 721 o2nm_node_put(node); 722 } 723 724 static void o2hb_set_quorum_device(struct o2hb_region *reg) 725 { 726 if (!o2hb_global_heartbeat_active()) 727 return; 728 729 /* Prevent race with o2hb_heartbeat_group_drop_item() */ 730 if (kthread_should_stop()) 731 return; 732 733 /* Tag region as quorum only after thread reaches steady state */ 734 if (atomic_read(®->hr_steady_iterations) != 0) 735 return; 736 737 spin_lock(&o2hb_live_lock); 738 739 if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap)) 740 goto unlock; 741 742 /* 743 * A region can be added to the quorum only when it sees all 744 * live nodes heartbeat on it. In other words, the region has been 745 * added to all nodes. 746 */ 747 if (memcmp(reg->hr_live_node_bitmap, o2hb_live_node_bitmap, 748 sizeof(o2hb_live_node_bitmap))) 749 goto unlock; 750 751 printk(KERN_NOTICE "o2hb: Region %s (%s) is now a quorum device\n", 752 config_item_name(®->hr_item), reg->hr_dev_name); 753 754 set_bit(reg->hr_region_num, o2hb_quorum_region_bitmap); 755 756 /* 757 * If global heartbeat active, unpin all regions if the 758 * region count > CUT_OFF 759 */ 760 if (bitmap_weight(o2hb_quorum_region_bitmap, 761 O2NM_MAX_REGIONS) > O2HB_PIN_CUT_OFF) 762 o2hb_region_unpin(NULL); 763 unlock: 764 spin_unlock(&o2hb_live_lock); 765 } 766 767 static int o2hb_check_slot(struct o2hb_region *reg, 768 struct o2hb_disk_slot *slot) 769 { 770 int changed = 0, gen_changed = 0; 771 struct o2hb_node_event event = 772 { .hn_item = LIST_HEAD_INIT(event.hn_item), }; 773 struct o2nm_node *node; 774 struct o2hb_disk_heartbeat_block *hb_block = reg->hr_tmp_block; 775 u64 cputime; 776 unsigned int dead_ms = o2hb_dead_threshold * O2HB_REGION_TIMEOUT_MS; 777 unsigned int slot_dead_ms; 778 int tmp; 779 int queued = 0; 780 781 memcpy(hb_block, slot->ds_raw_block, reg->hr_block_bytes); 782 783 /* 784 * If a node is no longer configured but is still in the livemap, we 785 * may need to clear that bit from the livemap. 786 */ 787 node = o2nm_get_node_by_num(slot->ds_node_num); 788 if (!node) { 789 spin_lock(&o2hb_live_lock); 790 tmp = test_bit(slot->ds_node_num, o2hb_live_node_bitmap); 791 spin_unlock(&o2hb_live_lock); 792 if (!tmp) 793 return 0; 794 } 795 796 if (!o2hb_verify_crc(reg, hb_block)) { 797 /* all paths from here will drop o2hb_live_lock for 798 * us. */ 799 spin_lock(&o2hb_live_lock); 800 801 /* Don't print an error on the console in this case - 802 * a freshly formatted heartbeat area will not have a 803 * crc set on it. */ 804 if (list_empty(&slot->ds_live_item)) 805 goto out; 806 807 /* The node is live but pushed out a bad crc. We 808 * consider it a transient miss but don't populate any 809 * other values as they may be junk. */ 810 mlog(ML_ERROR, "Node %d has written a bad crc to %s\n", 811 slot->ds_node_num, reg->hr_dev_name); 812 o2hb_dump_slot(hb_block); 813 814 slot->ds_equal_samples++; 815 goto fire_callbacks; 816 } 817 818 /* we don't care if these wrap.. the state transitions below 819 * clear at the right places */ 820 cputime = le64_to_cpu(hb_block->hb_seq); 821 if (slot->ds_last_time != cputime) 822 slot->ds_changed_samples++; 823 else 824 slot->ds_equal_samples++; 825 slot->ds_last_time = cputime; 826 827 /* The node changed heartbeat generations. We assume this to 828 * mean it dropped off but came back before we timed out. We 829 * want to consider it down for the time being but don't want 830 * to lose any changed_samples state we might build up to 831 * considering it live again. */ 832 if (slot->ds_last_generation != le64_to_cpu(hb_block->hb_generation)) { 833 gen_changed = 1; 834 slot->ds_equal_samples = 0; 835 mlog(ML_HEARTBEAT, "Node %d changed generation (0x%llx " 836 "to 0x%llx)\n", slot->ds_node_num, 837 (long long)slot->ds_last_generation, 838 (long long)le64_to_cpu(hb_block->hb_generation)); 839 } 840 841 slot->ds_last_generation = le64_to_cpu(hb_block->hb_generation); 842 843 mlog(ML_HEARTBEAT, "Slot %d gen 0x%llx cksum 0x%x " 844 "seq %llu last %llu changed %u equal %u\n", 845 slot->ds_node_num, (long long)slot->ds_last_generation, 846 le32_to_cpu(hb_block->hb_cksum), 847 (unsigned long long)le64_to_cpu(hb_block->hb_seq), 848 (unsigned long long)slot->ds_last_time, slot->ds_changed_samples, 849 slot->ds_equal_samples); 850 851 spin_lock(&o2hb_live_lock); 852 853 fire_callbacks: 854 /* dead nodes only come to life after some number of 855 * changes at any time during their dead time */ 856 if (list_empty(&slot->ds_live_item) && 857 slot->ds_changed_samples >= O2HB_LIVE_THRESHOLD) { 858 mlog(ML_HEARTBEAT, "Node %d (id 0x%llx) joined my region\n", 859 slot->ds_node_num, (long long)slot->ds_last_generation); 860 861 set_bit(slot->ds_node_num, reg->hr_live_node_bitmap); 862 863 /* first on the list generates a callback */ 864 if (list_empty(&o2hb_live_slots[slot->ds_node_num])) { 865 mlog(ML_HEARTBEAT, "o2hb: Add node %d to live nodes " 866 "bitmap\n", slot->ds_node_num); 867 set_bit(slot->ds_node_num, o2hb_live_node_bitmap); 868 869 o2hb_queue_node_event(&event, O2HB_NODE_UP_CB, node, 870 slot->ds_node_num); 871 872 changed = 1; 873 queued = 1; 874 } 875 876 list_add_tail(&slot->ds_live_item, 877 &o2hb_live_slots[slot->ds_node_num]); 878 879 slot->ds_equal_samples = 0; 880 881 /* We want to be sure that all nodes agree on the 882 * number of milliseconds before a node will be 883 * considered dead. The self-fencing timeout is 884 * computed from this value, and a discrepancy might 885 * result in heartbeat calling a node dead when it 886 * hasn't self-fenced yet. */ 887 slot_dead_ms = le32_to_cpu(hb_block->hb_dead_ms); 888 if (slot_dead_ms && slot_dead_ms != dead_ms) { 889 /* TODO: Perhaps we can fail the region here. */ 890 mlog(ML_ERROR, "Node %d on device %s has a dead count " 891 "of %u ms, but our count is %u ms.\n" 892 "Please double check your configuration values " 893 "for 'O2CB_HEARTBEAT_THRESHOLD'\n", 894 slot->ds_node_num, reg->hr_dev_name, slot_dead_ms, 895 dead_ms); 896 } 897 goto out; 898 } 899 900 /* if the list is dead, we're done.. */ 901 if (list_empty(&slot->ds_live_item)) 902 goto out; 903 904 /* live nodes only go dead after enough consequtive missed 905 * samples.. reset the missed counter whenever we see 906 * activity */ 907 if (slot->ds_equal_samples >= o2hb_dead_threshold || gen_changed) { 908 mlog(ML_HEARTBEAT, "Node %d left my region\n", 909 slot->ds_node_num); 910 911 clear_bit(slot->ds_node_num, reg->hr_live_node_bitmap); 912 913 /* last off the live_slot generates a callback */ 914 list_del_init(&slot->ds_live_item); 915 if (list_empty(&o2hb_live_slots[slot->ds_node_num])) { 916 mlog(ML_HEARTBEAT, "o2hb: Remove node %d from live " 917 "nodes bitmap\n", slot->ds_node_num); 918 clear_bit(slot->ds_node_num, o2hb_live_node_bitmap); 919 920 /* node can be null */ 921 o2hb_queue_node_event(&event, O2HB_NODE_DOWN_CB, 922 node, slot->ds_node_num); 923 924 changed = 1; 925 queued = 1; 926 } 927 928 /* We don't clear this because the node is still 929 * actually writing new blocks. */ 930 if (!gen_changed) 931 slot->ds_changed_samples = 0; 932 goto out; 933 } 934 if (slot->ds_changed_samples) { 935 slot->ds_changed_samples = 0; 936 slot->ds_equal_samples = 0; 937 } 938 out: 939 spin_unlock(&o2hb_live_lock); 940 941 if (queued) 942 o2hb_run_event_list(&event); 943 944 if (node) 945 o2nm_node_put(node); 946 return changed; 947 } 948 949 static int o2hb_highest_node(unsigned long *nodes, int numbits) 950 { 951 return find_last_bit(nodes, numbits); 952 } 953 954 static int o2hb_do_disk_heartbeat(struct o2hb_region *reg) 955 { 956 int i, ret, highest_node; 957 int membership_change = 0, own_slot_ok = 0; 958 unsigned long configured_nodes[BITS_TO_LONGS(O2NM_MAX_NODES)]; 959 unsigned long live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)]; 960 struct o2hb_bio_wait_ctxt write_wc; 961 962 ret = o2nm_configured_node_map(configured_nodes, 963 sizeof(configured_nodes)); 964 if (ret) { 965 mlog_errno(ret); 966 goto bail; 967 } 968 969 /* 970 * If a node is not configured but is in the livemap, we still need 971 * to read the slot so as to be able to remove it from the livemap. 972 */ 973 o2hb_fill_node_map(live_node_bitmap, sizeof(live_node_bitmap)); 974 i = -1; 975 while ((i = find_next_bit(live_node_bitmap, 976 O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) { 977 set_bit(i, configured_nodes); 978 } 979 980 highest_node = o2hb_highest_node(configured_nodes, O2NM_MAX_NODES); 981 if (highest_node >= O2NM_MAX_NODES) { 982 mlog(ML_NOTICE, "o2hb: No configured nodes found!\n"); 983 ret = -EINVAL; 984 goto bail; 985 } 986 987 /* No sense in reading the slots of nodes that don't exist 988 * yet. Of course, if the node definitions have holes in them 989 * then we're reading an empty slot anyway... Consider this 990 * best-effort. */ 991 ret = o2hb_read_slots(reg, highest_node + 1); 992 if (ret < 0) { 993 mlog_errno(ret); 994 goto bail; 995 } 996 997 /* With an up to date view of the slots, we can check that no 998 * other node has been improperly configured to heartbeat in 999 * our slot. */ 1000 own_slot_ok = o2hb_check_own_slot(reg); 1001 1002 /* fill in the proper info for our next heartbeat */ 1003 o2hb_prepare_block(reg, reg->hr_generation); 1004 1005 ret = o2hb_issue_node_write(reg, &write_wc); 1006 if (ret < 0) { 1007 mlog_errno(ret); 1008 goto bail; 1009 } 1010 1011 i = -1; 1012 while((i = find_next_bit(configured_nodes, 1013 O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) { 1014 membership_change |= o2hb_check_slot(reg, ®->hr_slots[i]); 1015 } 1016 1017 /* 1018 * We have to be sure we've advertised ourselves on disk 1019 * before we can go to steady state. This ensures that 1020 * people we find in our steady state have seen us. 1021 */ 1022 o2hb_wait_on_io(reg, &write_wc); 1023 if (write_wc.wc_error) { 1024 /* Do not re-arm the write timeout on I/O error - we 1025 * can't be sure that the new block ever made it to 1026 * disk */ 1027 mlog(ML_ERROR, "Write error %d on device \"%s\"\n", 1028 write_wc.wc_error, reg->hr_dev_name); 1029 ret = write_wc.wc_error; 1030 goto bail; 1031 } 1032 1033 /* Skip disarming the timeout if own slot has stale/bad data */ 1034 if (own_slot_ok) { 1035 o2hb_set_quorum_device(reg); 1036 o2hb_arm_write_timeout(reg); 1037 } 1038 1039 bail: 1040 /* let the person who launched us know when things are steady */ 1041 if (atomic_read(®->hr_steady_iterations) != 0) { 1042 if (!ret && own_slot_ok && !membership_change) { 1043 if (atomic_dec_and_test(®->hr_steady_iterations)) 1044 wake_up(&o2hb_steady_queue); 1045 } 1046 } 1047 1048 if (atomic_read(®->hr_steady_iterations) != 0) { 1049 if (atomic_dec_and_test(®->hr_unsteady_iterations)) { 1050 printk(KERN_NOTICE "o2hb: Unable to stabilize " 1051 "heartbeart on region %s (%s)\n", 1052 config_item_name(®->hr_item), 1053 reg->hr_dev_name); 1054 atomic_set(®->hr_steady_iterations, 0); 1055 reg->hr_aborted_start = 1; 1056 wake_up(&o2hb_steady_queue); 1057 ret = -EIO; 1058 } 1059 } 1060 1061 return ret; 1062 } 1063 1064 /* Subtract b from a, storing the result in a. a *must* have a larger 1065 * value than b. */ 1066 static void o2hb_tv_subtract(struct timeval *a, 1067 struct timeval *b) 1068 { 1069 /* just return 0 when a is after b */ 1070 if (a->tv_sec < b->tv_sec || 1071 (a->tv_sec == b->tv_sec && a->tv_usec < b->tv_usec)) { 1072 a->tv_sec = 0; 1073 a->tv_usec = 0; 1074 return; 1075 } 1076 1077 a->tv_sec -= b->tv_sec; 1078 a->tv_usec -= b->tv_usec; 1079 while ( a->tv_usec < 0 ) { 1080 a->tv_sec--; 1081 a->tv_usec += 1000000; 1082 } 1083 } 1084 1085 static unsigned int o2hb_elapsed_msecs(struct timeval *start, 1086 struct timeval *end) 1087 { 1088 struct timeval res = *end; 1089 1090 o2hb_tv_subtract(&res, start); 1091 1092 return res.tv_sec * 1000 + res.tv_usec / 1000; 1093 } 1094 1095 /* 1096 * we ride the region ref that the region dir holds. before the region 1097 * dir is removed and drops it ref it will wait to tear down this 1098 * thread. 1099 */ 1100 static int o2hb_thread(void *data) 1101 { 1102 int i, ret; 1103 struct o2hb_region *reg = data; 1104 struct o2hb_bio_wait_ctxt write_wc; 1105 struct timeval before_hb, after_hb; 1106 unsigned int elapsed_msec; 1107 1108 mlog(ML_HEARTBEAT|ML_KTHREAD, "hb thread running\n"); 1109 1110 set_user_nice(current, MIN_NICE); 1111 1112 /* Pin node */ 1113 o2nm_depend_this_node(); 1114 1115 while (!kthread_should_stop() && 1116 !reg->hr_unclean_stop && !reg->hr_aborted_start) { 1117 /* We track the time spent inside 1118 * o2hb_do_disk_heartbeat so that we avoid more than 1119 * hr_timeout_ms between disk writes. On busy systems 1120 * this should result in a heartbeat which is less 1121 * likely to time itself out. */ 1122 do_gettimeofday(&before_hb); 1123 1124 ret = o2hb_do_disk_heartbeat(reg); 1125 1126 do_gettimeofday(&after_hb); 1127 elapsed_msec = o2hb_elapsed_msecs(&before_hb, &after_hb); 1128 1129 mlog(ML_HEARTBEAT, 1130 "start = %lu.%lu, end = %lu.%lu, msec = %u\n", 1131 before_hb.tv_sec, (unsigned long) before_hb.tv_usec, 1132 after_hb.tv_sec, (unsigned long) after_hb.tv_usec, 1133 elapsed_msec); 1134 1135 if (!kthread_should_stop() && 1136 elapsed_msec < reg->hr_timeout_ms) { 1137 /* the kthread api has blocked signals for us so no 1138 * need to record the return value. */ 1139 msleep_interruptible(reg->hr_timeout_ms - elapsed_msec); 1140 } 1141 } 1142 1143 o2hb_disarm_write_timeout(reg); 1144 1145 /* unclean stop is only used in very bad situation */ 1146 for(i = 0; !reg->hr_unclean_stop && i < reg->hr_blocks; i++) 1147 o2hb_shutdown_slot(®->hr_slots[i]); 1148 1149 /* Explicit down notification - avoid forcing the other nodes 1150 * to timeout on this region when we could just as easily 1151 * write a clear generation - thus indicating to them that 1152 * this node has left this region. 1153 */ 1154 if (!reg->hr_unclean_stop && !reg->hr_aborted_start) { 1155 o2hb_prepare_block(reg, 0); 1156 ret = o2hb_issue_node_write(reg, &write_wc); 1157 if (ret == 0) 1158 o2hb_wait_on_io(reg, &write_wc); 1159 else 1160 mlog_errno(ret); 1161 } 1162 1163 /* Unpin node */ 1164 o2nm_undepend_this_node(); 1165 1166 mlog(ML_HEARTBEAT|ML_KTHREAD, "o2hb thread exiting\n"); 1167 1168 return 0; 1169 } 1170 1171 #ifdef CONFIG_DEBUG_FS 1172 static int o2hb_debug_open(struct inode *inode, struct file *file) 1173 { 1174 struct o2hb_debug_buf *db = inode->i_private; 1175 struct o2hb_region *reg; 1176 unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)]; 1177 unsigned long lts; 1178 char *buf = NULL; 1179 int i = -1; 1180 int out = 0; 1181 1182 /* max_nodes should be the largest bitmap we pass here */ 1183 BUG_ON(sizeof(map) < db->db_size); 1184 1185 buf = kmalloc(PAGE_SIZE, GFP_KERNEL); 1186 if (!buf) 1187 goto bail; 1188 1189 switch (db->db_type) { 1190 case O2HB_DB_TYPE_LIVENODES: 1191 case O2HB_DB_TYPE_LIVEREGIONS: 1192 case O2HB_DB_TYPE_QUORUMREGIONS: 1193 case O2HB_DB_TYPE_FAILEDREGIONS: 1194 spin_lock(&o2hb_live_lock); 1195 memcpy(map, db->db_data, db->db_size); 1196 spin_unlock(&o2hb_live_lock); 1197 break; 1198 1199 case O2HB_DB_TYPE_REGION_LIVENODES: 1200 spin_lock(&o2hb_live_lock); 1201 reg = (struct o2hb_region *)db->db_data; 1202 memcpy(map, reg->hr_live_node_bitmap, db->db_size); 1203 spin_unlock(&o2hb_live_lock); 1204 break; 1205 1206 case O2HB_DB_TYPE_REGION_NUMBER: 1207 reg = (struct o2hb_region *)db->db_data; 1208 out += snprintf(buf + out, PAGE_SIZE - out, "%d\n", 1209 reg->hr_region_num); 1210 goto done; 1211 1212 case O2HB_DB_TYPE_REGION_ELAPSED_TIME: 1213 reg = (struct o2hb_region *)db->db_data; 1214 lts = reg->hr_last_timeout_start; 1215 /* If 0, it has never been set before */ 1216 if (lts) 1217 lts = jiffies_to_msecs(jiffies - lts); 1218 out += snprintf(buf + out, PAGE_SIZE - out, "%lu\n", lts); 1219 goto done; 1220 1221 case O2HB_DB_TYPE_REGION_PINNED: 1222 reg = (struct o2hb_region *)db->db_data; 1223 out += snprintf(buf + out, PAGE_SIZE - out, "%u\n", 1224 !!reg->hr_item_pinned); 1225 goto done; 1226 1227 default: 1228 goto done; 1229 } 1230 1231 while ((i = find_next_bit(map, db->db_len, i + 1)) < db->db_len) 1232 out += snprintf(buf + out, PAGE_SIZE - out, "%d ", i); 1233 out += snprintf(buf + out, PAGE_SIZE - out, "\n"); 1234 1235 done: 1236 i_size_write(inode, out); 1237 1238 file->private_data = buf; 1239 1240 return 0; 1241 bail: 1242 return -ENOMEM; 1243 } 1244 1245 static int o2hb_debug_release(struct inode *inode, struct file *file) 1246 { 1247 kfree(file->private_data); 1248 return 0; 1249 } 1250 1251 static ssize_t o2hb_debug_read(struct file *file, char __user *buf, 1252 size_t nbytes, loff_t *ppos) 1253 { 1254 return simple_read_from_buffer(buf, nbytes, ppos, file->private_data, 1255 i_size_read(file->f_mapping->host)); 1256 } 1257 #else 1258 static int o2hb_debug_open(struct inode *inode, struct file *file) 1259 { 1260 return 0; 1261 } 1262 static int o2hb_debug_release(struct inode *inode, struct file *file) 1263 { 1264 return 0; 1265 } 1266 static ssize_t o2hb_debug_read(struct file *file, char __user *buf, 1267 size_t nbytes, loff_t *ppos) 1268 { 1269 return 0; 1270 } 1271 #endif /* CONFIG_DEBUG_FS */ 1272 1273 static const struct file_operations o2hb_debug_fops = { 1274 .open = o2hb_debug_open, 1275 .release = o2hb_debug_release, 1276 .read = o2hb_debug_read, 1277 .llseek = generic_file_llseek, 1278 }; 1279 1280 void o2hb_exit(void) 1281 { 1282 kfree(o2hb_db_livenodes); 1283 kfree(o2hb_db_liveregions); 1284 kfree(o2hb_db_quorumregions); 1285 kfree(o2hb_db_failedregions); 1286 debugfs_remove(o2hb_debug_failedregions); 1287 debugfs_remove(o2hb_debug_quorumregions); 1288 debugfs_remove(o2hb_debug_liveregions); 1289 debugfs_remove(o2hb_debug_livenodes); 1290 debugfs_remove(o2hb_debug_dir); 1291 } 1292 1293 static struct dentry *o2hb_debug_create(const char *name, struct dentry *dir, 1294 struct o2hb_debug_buf **db, int db_len, 1295 int type, int size, int len, void *data) 1296 { 1297 *db = kmalloc(db_len, GFP_KERNEL); 1298 if (!*db) 1299 return NULL; 1300 1301 (*db)->db_type = type; 1302 (*db)->db_size = size; 1303 (*db)->db_len = len; 1304 (*db)->db_data = data; 1305 1306 return debugfs_create_file(name, S_IFREG|S_IRUSR, dir, *db, 1307 &o2hb_debug_fops); 1308 } 1309 1310 static int o2hb_debug_init(void) 1311 { 1312 int ret = -ENOMEM; 1313 1314 o2hb_debug_dir = debugfs_create_dir(O2HB_DEBUG_DIR, NULL); 1315 if (!o2hb_debug_dir) { 1316 mlog_errno(ret); 1317 goto bail; 1318 } 1319 1320 o2hb_debug_livenodes = o2hb_debug_create(O2HB_DEBUG_LIVENODES, 1321 o2hb_debug_dir, 1322 &o2hb_db_livenodes, 1323 sizeof(*o2hb_db_livenodes), 1324 O2HB_DB_TYPE_LIVENODES, 1325 sizeof(o2hb_live_node_bitmap), 1326 O2NM_MAX_NODES, 1327 o2hb_live_node_bitmap); 1328 if (!o2hb_debug_livenodes) { 1329 mlog_errno(ret); 1330 goto bail; 1331 } 1332 1333 o2hb_debug_liveregions = o2hb_debug_create(O2HB_DEBUG_LIVEREGIONS, 1334 o2hb_debug_dir, 1335 &o2hb_db_liveregions, 1336 sizeof(*o2hb_db_liveregions), 1337 O2HB_DB_TYPE_LIVEREGIONS, 1338 sizeof(o2hb_live_region_bitmap), 1339 O2NM_MAX_REGIONS, 1340 o2hb_live_region_bitmap); 1341 if (!o2hb_debug_liveregions) { 1342 mlog_errno(ret); 1343 goto bail; 1344 } 1345 1346 o2hb_debug_quorumregions = 1347 o2hb_debug_create(O2HB_DEBUG_QUORUMREGIONS, 1348 o2hb_debug_dir, 1349 &o2hb_db_quorumregions, 1350 sizeof(*o2hb_db_quorumregions), 1351 O2HB_DB_TYPE_QUORUMREGIONS, 1352 sizeof(o2hb_quorum_region_bitmap), 1353 O2NM_MAX_REGIONS, 1354 o2hb_quorum_region_bitmap); 1355 if (!o2hb_debug_quorumregions) { 1356 mlog_errno(ret); 1357 goto bail; 1358 } 1359 1360 o2hb_debug_failedregions = 1361 o2hb_debug_create(O2HB_DEBUG_FAILEDREGIONS, 1362 o2hb_debug_dir, 1363 &o2hb_db_failedregions, 1364 sizeof(*o2hb_db_failedregions), 1365 O2HB_DB_TYPE_FAILEDREGIONS, 1366 sizeof(o2hb_failed_region_bitmap), 1367 O2NM_MAX_REGIONS, 1368 o2hb_failed_region_bitmap); 1369 if (!o2hb_debug_failedregions) { 1370 mlog_errno(ret); 1371 goto bail; 1372 } 1373 1374 ret = 0; 1375 bail: 1376 if (ret) 1377 o2hb_exit(); 1378 1379 return ret; 1380 } 1381 1382 int o2hb_init(void) 1383 { 1384 int i; 1385 1386 for (i = 0; i < ARRAY_SIZE(o2hb_callbacks); i++) 1387 INIT_LIST_HEAD(&o2hb_callbacks[i].list); 1388 1389 for (i = 0; i < ARRAY_SIZE(o2hb_live_slots); i++) 1390 INIT_LIST_HEAD(&o2hb_live_slots[i]); 1391 1392 INIT_LIST_HEAD(&o2hb_node_events); 1393 1394 memset(o2hb_live_node_bitmap, 0, sizeof(o2hb_live_node_bitmap)); 1395 memset(o2hb_region_bitmap, 0, sizeof(o2hb_region_bitmap)); 1396 memset(o2hb_live_region_bitmap, 0, sizeof(o2hb_live_region_bitmap)); 1397 memset(o2hb_quorum_region_bitmap, 0, sizeof(o2hb_quorum_region_bitmap)); 1398 memset(o2hb_failed_region_bitmap, 0, sizeof(o2hb_failed_region_bitmap)); 1399 1400 o2hb_dependent_users = 0; 1401 1402 return o2hb_debug_init(); 1403 } 1404 1405 /* if we're already in a callback then we're already serialized by the sem */ 1406 static void o2hb_fill_node_map_from_callback(unsigned long *map, 1407 unsigned bytes) 1408 { 1409 BUG_ON(bytes < (BITS_TO_LONGS(O2NM_MAX_NODES) * sizeof(unsigned long))); 1410 1411 memcpy(map, &o2hb_live_node_bitmap, bytes); 1412 } 1413 1414 /* 1415 * get a map of all nodes that are heartbeating in any regions 1416 */ 1417 void o2hb_fill_node_map(unsigned long *map, unsigned bytes) 1418 { 1419 /* callers want to serialize this map and callbacks so that they 1420 * can trust that they don't miss nodes coming to the party */ 1421 down_read(&o2hb_callback_sem); 1422 spin_lock(&o2hb_live_lock); 1423 o2hb_fill_node_map_from_callback(map, bytes); 1424 spin_unlock(&o2hb_live_lock); 1425 up_read(&o2hb_callback_sem); 1426 } 1427 EXPORT_SYMBOL_GPL(o2hb_fill_node_map); 1428 1429 /* 1430 * heartbeat configfs bits. The heartbeat set is a default set under 1431 * the cluster set in nodemanager.c. 1432 */ 1433 1434 static struct o2hb_region *to_o2hb_region(struct config_item *item) 1435 { 1436 return item ? container_of(item, struct o2hb_region, hr_item) : NULL; 1437 } 1438 1439 /* drop_item only drops its ref after killing the thread, nothing should 1440 * be using the region anymore. this has to clean up any state that 1441 * attributes might have built up. */ 1442 static void o2hb_region_release(struct config_item *item) 1443 { 1444 int i; 1445 struct page *page; 1446 struct o2hb_region *reg = to_o2hb_region(item); 1447 1448 mlog(ML_HEARTBEAT, "hb region release (%s)\n", reg->hr_dev_name); 1449 1450 kfree(reg->hr_tmp_block); 1451 1452 if (reg->hr_slot_data) { 1453 for (i = 0; i < reg->hr_num_pages; i++) { 1454 page = reg->hr_slot_data[i]; 1455 if (page) 1456 __free_page(page); 1457 } 1458 kfree(reg->hr_slot_data); 1459 } 1460 1461 if (reg->hr_bdev) 1462 blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE); 1463 1464 kfree(reg->hr_slots); 1465 1466 kfree(reg->hr_db_regnum); 1467 kfree(reg->hr_db_livenodes); 1468 debugfs_remove(reg->hr_debug_livenodes); 1469 debugfs_remove(reg->hr_debug_regnum); 1470 debugfs_remove(reg->hr_debug_elapsed_time); 1471 debugfs_remove(reg->hr_debug_pinned); 1472 debugfs_remove(reg->hr_debug_dir); 1473 1474 spin_lock(&o2hb_live_lock); 1475 list_del(®->hr_all_item); 1476 spin_unlock(&o2hb_live_lock); 1477 1478 kfree(reg); 1479 } 1480 1481 static int o2hb_read_block_input(struct o2hb_region *reg, 1482 const char *page, 1483 size_t count, 1484 unsigned long *ret_bytes, 1485 unsigned int *ret_bits) 1486 { 1487 unsigned long bytes; 1488 char *p = (char *)page; 1489 1490 bytes = simple_strtoul(p, &p, 0); 1491 if (!p || (*p && (*p != '\n'))) 1492 return -EINVAL; 1493 1494 /* Heartbeat and fs min / max block sizes are the same. */ 1495 if (bytes > 4096 || bytes < 512) 1496 return -ERANGE; 1497 if (hweight16(bytes) != 1) 1498 return -EINVAL; 1499 1500 if (ret_bytes) 1501 *ret_bytes = bytes; 1502 if (ret_bits) 1503 *ret_bits = ffs(bytes) - 1; 1504 1505 return 0; 1506 } 1507 1508 static ssize_t o2hb_region_block_bytes_read(struct o2hb_region *reg, 1509 char *page) 1510 { 1511 return sprintf(page, "%u\n", reg->hr_block_bytes); 1512 } 1513 1514 static ssize_t o2hb_region_block_bytes_write(struct o2hb_region *reg, 1515 const char *page, 1516 size_t count) 1517 { 1518 int status; 1519 unsigned long block_bytes; 1520 unsigned int block_bits; 1521 1522 if (reg->hr_bdev) 1523 return -EINVAL; 1524 1525 status = o2hb_read_block_input(reg, page, count, 1526 &block_bytes, &block_bits); 1527 if (status) 1528 return status; 1529 1530 reg->hr_block_bytes = (unsigned int)block_bytes; 1531 reg->hr_block_bits = block_bits; 1532 1533 return count; 1534 } 1535 1536 static ssize_t o2hb_region_start_block_read(struct o2hb_region *reg, 1537 char *page) 1538 { 1539 return sprintf(page, "%llu\n", reg->hr_start_block); 1540 } 1541 1542 static ssize_t o2hb_region_start_block_write(struct o2hb_region *reg, 1543 const char *page, 1544 size_t count) 1545 { 1546 unsigned long long tmp; 1547 char *p = (char *)page; 1548 1549 if (reg->hr_bdev) 1550 return -EINVAL; 1551 1552 tmp = simple_strtoull(p, &p, 0); 1553 if (!p || (*p && (*p != '\n'))) 1554 return -EINVAL; 1555 1556 reg->hr_start_block = tmp; 1557 1558 return count; 1559 } 1560 1561 static ssize_t o2hb_region_blocks_read(struct o2hb_region *reg, 1562 char *page) 1563 { 1564 return sprintf(page, "%d\n", reg->hr_blocks); 1565 } 1566 1567 static ssize_t o2hb_region_blocks_write(struct o2hb_region *reg, 1568 const char *page, 1569 size_t count) 1570 { 1571 unsigned long tmp; 1572 char *p = (char *)page; 1573 1574 if (reg->hr_bdev) 1575 return -EINVAL; 1576 1577 tmp = simple_strtoul(p, &p, 0); 1578 if (!p || (*p && (*p != '\n'))) 1579 return -EINVAL; 1580 1581 if (tmp > O2NM_MAX_NODES || tmp == 0) 1582 return -ERANGE; 1583 1584 reg->hr_blocks = (unsigned int)tmp; 1585 1586 return count; 1587 } 1588 1589 static ssize_t o2hb_region_dev_read(struct o2hb_region *reg, 1590 char *page) 1591 { 1592 unsigned int ret = 0; 1593 1594 if (reg->hr_bdev) 1595 ret = sprintf(page, "%s\n", reg->hr_dev_name); 1596 1597 return ret; 1598 } 1599 1600 static void o2hb_init_region_params(struct o2hb_region *reg) 1601 { 1602 reg->hr_slots_per_page = PAGE_CACHE_SIZE >> reg->hr_block_bits; 1603 reg->hr_timeout_ms = O2HB_REGION_TIMEOUT_MS; 1604 1605 mlog(ML_HEARTBEAT, "hr_start_block = %llu, hr_blocks = %u\n", 1606 reg->hr_start_block, reg->hr_blocks); 1607 mlog(ML_HEARTBEAT, "hr_block_bytes = %u, hr_block_bits = %u\n", 1608 reg->hr_block_bytes, reg->hr_block_bits); 1609 mlog(ML_HEARTBEAT, "hr_timeout_ms = %u\n", reg->hr_timeout_ms); 1610 mlog(ML_HEARTBEAT, "dead threshold = %u\n", o2hb_dead_threshold); 1611 } 1612 1613 static int o2hb_map_slot_data(struct o2hb_region *reg) 1614 { 1615 int i, j; 1616 unsigned int last_slot; 1617 unsigned int spp = reg->hr_slots_per_page; 1618 struct page *page; 1619 char *raw; 1620 struct o2hb_disk_slot *slot; 1621 1622 reg->hr_tmp_block = kmalloc(reg->hr_block_bytes, GFP_KERNEL); 1623 if (reg->hr_tmp_block == NULL) { 1624 mlog_errno(-ENOMEM); 1625 return -ENOMEM; 1626 } 1627 1628 reg->hr_slots = kcalloc(reg->hr_blocks, 1629 sizeof(struct o2hb_disk_slot), GFP_KERNEL); 1630 if (reg->hr_slots == NULL) { 1631 mlog_errno(-ENOMEM); 1632 return -ENOMEM; 1633 } 1634 1635 for(i = 0; i < reg->hr_blocks; i++) { 1636 slot = ®->hr_slots[i]; 1637 slot->ds_node_num = i; 1638 INIT_LIST_HEAD(&slot->ds_live_item); 1639 slot->ds_raw_block = NULL; 1640 } 1641 1642 reg->hr_num_pages = (reg->hr_blocks + spp - 1) / spp; 1643 mlog(ML_HEARTBEAT, "Going to require %u pages to cover %u blocks " 1644 "at %u blocks per page\n", 1645 reg->hr_num_pages, reg->hr_blocks, spp); 1646 1647 reg->hr_slot_data = kcalloc(reg->hr_num_pages, sizeof(struct page *), 1648 GFP_KERNEL); 1649 if (!reg->hr_slot_data) { 1650 mlog_errno(-ENOMEM); 1651 return -ENOMEM; 1652 } 1653 1654 for(i = 0; i < reg->hr_num_pages; i++) { 1655 page = alloc_page(GFP_KERNEL); 1656 if (!page) { 1657 mlog_errno(-ENOMEM); 1658 return -ENOMEM; 1659 } 1660 1661 reg->hr_slot_data[i] = page; 1662 1663 last_slot = i * spp; 1664 raw = page_address(page); 1665 for (j = 0; 1666 (j < spp) && ((j + last_slot) < reg->hr_blocks); 1667 j++) { 1668 BUG_ON((j + last_slot) >= reg->hr_blocks); 1669 1670 slot = ®->hr_slots[j + last_slot]; 1671 slot->ds_raw_block = 1672 (struct o2hb_disk_heartbeat_block *) raw; 1673 1674 raw += reg->hr_block_bytes; 1675 } 1676 } 1677 1678 return 0; 1679 } 1680 1681 /* Read in all the slots available and populate the tracking 1682 * structures so that we can start with a baseline idea of what's 1683 * there. */ 1684 static int o2hb_populate_slot_data(struct o2hb_region *reg) 1685 { 1686 int ret, i; 1687 struct o2hb_disk_slot *slot; 1688 struct o2hb_disk_heartbeat_block *hb_block; 1689 1690 ret = o2hb_read_slots(reg, reg->hr_blocks); 1691 if (ret) { 1692 mlog_errno(ret); 1693 goto out; 1694 } 1695 1696 /* We only want to get an idea of the values initially in each 1697 * slot, so we do no verification - o2hb_check_slot will 1698 * actually determine if each configured slot is valid and 1699 * whether any values have changed. */ 1700 for(i = 0; i < reg->hr_blocks; i++) { 1701 slot = ®->hr_slots[i]; 1702 hb_block = (struct o2hb_disk_heartbeat_block *) slot->ds_raw_block; 1703 1704 /* Only fill the values that o2hb_check_slot uses to 1705 * determine changing slots */ 1706 slot->ds_last_time = le64_to_cpu(hb_block->hb_seq); 1707 slot->ds_last_generation = le64_to_cpu(hb_block->hb_generation); 1708 } 1709 1710 out: 1711 return ret; 1712 } 1713 1714 /* this is acting as commit; we set up all of hr_bdev and hr_task or nothing */ 1715 static ssize_t o2hb_region_dev_write(struct o2hb_region *reg, 1716 const char *page, 1717 size_t count) 1718 { 1719 struct task_struct *hb_task; 1720 long fd; 1721 int sectsize; 1722 char *p = (char *)page; 1723 struct fd f; 1724 struct inode *inode; 1725 ssize_t ret = -EINVAL; 1726 int live_threshold; 1727 1728 if (reg->hr_bdev) 1729 goto out; 1730 1731 /* We can't heartbeat without having had our node number 1732 * configured yet. */ 1733 if (o2nm_this_node() == O2NM_MAX_NODES) 1734 goto out; 1735 1736 fd = simple_strtol(p, &p, 0); 1737 if (!p || (*p && (*p != '\n'))) 1738 goto out; 1739 1740 if (fd < 0 || fd >= INT_MAX) 1741 goto out; 1742 1743 f = fdget(fd); 1744 if (f.file == NULL) 1745 goto out; 1746 1747 if (reg->hr_blocks == 0 || reg->hr_start_block == 0 || 1748 reg->hr_block_bytes == 0) 1749 goto out2; 1750 1751 inode = igrab(f.file->f_mapping->host); 1752 if (inode == NULL) 1753 goto out2; 1754 1755 if (!S_ISBLK(inode->i_mode)) 1756 goto out3; 1757 1758 reg->hr_bdev = I_BDEV(f.file->f_mapping->host); 1759 ret = blkdev_get(reg->hr_bdev, FMODE_WRITE | FMODE_READ, NULL); 1760 if (ret) { 1761 reg->hr_bdev = NULL; 1762 goto out3; 1763 } 1764 inode = NULL; 1765 1766 bdevname(reg->hr_bdev, reg->hr_dev_name); 1767 1768 sectsize = bdev_logical_block_size(reg->hr_bdev); 1769 if (sectsize != reg->hr_block_bytes) { 1770 mlog(ML_ERROR, 1771 "blocksize %u incorrect for device, expected %d", 1772 reg->hr_block_bytes, sectsize); 1773 ret = -EINVAL; 1774 goto out3; 1775 } 1776 1777 o2hb_init_region_params(reg); 1778 1779 /* Generation of zero is invalid */ 1780 do { 1781 get_random_bytes(®->hr_generation, 1782 sizeof(reg->hr_generation)); 1783 } while (reg->hr_generation == 0); 1784 1785 ret = o2hb_map_slot_data(reg); 1786 if (ret) { 1787 mlog_errno(ret); 1788 goto out3; 1789 } 1790 1791 ret = o2hb_populate_slot_data(reg); 1792 if (ret) { 1793 mlog_errno(ret); 1794 goto out3; 1795 } 1796 1797 INIT_DELAYED_WORK(®->hr_write_timeout_work, o2hb_write_timeout); 1798 1799 /* 1800 * A node is considered live after it has beat LIVE_THRESHOLD 1801 * times. We're not steady until we've given them a chance 1802 * _after_ our first read. 1803 * The default threshold is bare minimum so as to limit the delay 1804 * during mounts. For global heartbeat, the threshold doubled for the 1805 * first region. 1806 */ 1807 live_threshold = O2HB_LIVE_THRESHOLD; 1808 if (o2hb_global_heartbeat_active()) { 1809 spin_lock(&o2hb_live_lock); 1810 if (bitmap_weight(o2hb_region_bitmap, O2NM_MAX_REGIONS) == 1) 1811 live_threshold <<= 1; 1812 spin_unlock(&o2hb_live_lock); 1813 } 1814 ++live_threshold; 1815 atomic_set(®->hr_steady_iterations, live_threshold); 1816 /* unsteady_iterations is double the steady_iterations */ 1817 atomic_set(®->hr_unsteady_iterations, (live_threshold << 1)); 1818 1819 hb_task = kthread_run(o2hb_thread, reg, "o2hb-%s", 1820 reg->hr_item.ci_name); 1821 if (IS_ERR(hb_task)) { 1822 ret = PTR_ERR(hb_task); 1823 mlog_errno(ret); 1824 goto out3; 1825 } 1826 1827 spin_lock(&o2hb_live_lock); 1828 reg->hr_task = hb_task; 1829 spin_unlock(&o2hb_live_lock); 1830 1831 ret = wait_event_interruptible(o2hb_steady_queue, 1832 atomic_read(®->hr_steady_iterations) == 0); 1833 if (ret) { 1834 atomic_set(®->hr_steady_iterations, 0); 1835 reg->hr_aborted_start = 1; 1836 } 1837 1838 if (reg->hr_aborted_start) { 1839 ret = -EIO; 1840 goto out3; 1841 } 1842 1843 /* Ok, we were woken. Make sure it wasn't by drop_item() */ 1844 spin_lock(&o2hb_live_lock); 1845 hb_task = reg->hr_task; 1846 if (o2hb_global_heartbeat_active()) 1847 set_bit(reg->hr_region_num, o2hb_live_region_bitmap); 1848 spin_unlock(&o2hb_live_lock); 1849 1850 if (hb_task) 1851 ret = count; 1852 else 1853 ret = -EIO; 1854 1855 if (hb_task && o2hb_global_heartbeat_active()) 1856 printk(KERN_NOTICE "o2hb: Heartbeat started on region %s (%s)\n", 1857 config_item_name(®->hr_item), reg->hr_dev_name); 1858 1859 out3: 1860 iput(inode); 1861 out2: 1862 fdput(f); 1863 out: 1864 if (ret < 0) { 1865 if (reg->hr_bdev) { 1866 blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE); 1867 reg->hr_bdev = NULL; 1868 } 1869 } 1870 return ret; 1871 } 1872 1873 static ssize_t o2hb_region_pid_read(struct o2hb_region *reg, 1874 char *page) 1875 { 1876 pid_t pid = 0; 1877 1878 spin_lock(&o2hb_live_lock); 1879 if (reg->hr_task) 1880 pid = task_pid_nr(reg->hr_task); 1881 spin_unlock(&o2hb_live_lock); 1882 1883 if (!pid) 1884 return 0; 1885 1886 return sprintf(page, "%u\n", pid); 1887 } 1888 1889 struct o2hb_region_attribute { 1890 struct configfs_attribute attr; 1891 ssize_t (*show)(struct o2hb_region *, char *); 1892 ssize_t (*store)(struct o2hb_region *, const char *, size_t); 1893 }; 1894 1895 static struct o2hb_region_attribute o2hb_region_attr_block_bytes = { 1896 .attr = { .ca_owner = THIS_MODULE, 1897 .ca_name = "block_bytes", 1898 .ca_mode = S_IRUGO | S_IWUSR }, 1899 .show = o2hb_region_block_bytes_read, 1900 .store = o2hb_region_block_bytes_write, 1901 }; 1902 1903 static struct o2hb_region_attribute o2hb_region_attr_start_block = { 1904 .attr = { .ca_owner = THIS_MODULE, 1905 .ca_name = "start_block", 1906 .ca_mode = S_IRUGO | S_IWUSR }, 1907 .show = o2hb_region_start_block_read, 1908 .store = o2hb_region_start_block_write, 1909 }; 1910 1911 static struct o2hb_region_attribute o2hb_region_attr_blocks = { 1912 .attr = { .ca_owner = THIS_MODULE, 1913 .ca_name = "blocks", 1914 .ca_mode = S_IRUGO | S_IWUSR }, 1915 .show = o2hb_region_blocks_read, 1916 .store = o2hb_region_blocks_write, 1917 }; 1918 1919 static struct o2hb_region_attribute o2hb_region_attr_dev = { 1920 .attr = { .ca_owner = THIS_MODULE, 1921 .ca_name = "dev", 1922 .ca_mode = S_IRUGO | S_IWUSR }, 1923 .show = o2hb_region_dev_read, 1924 .store = o2hb_region_dev_write, 1925 }; 1926 1927 static struct o2hb_region_attribute o2hb_region_attr_pid = { 1928 .attr = { .ca_owner = THIS_MODULE, 1929 .ca_name = "pid", 1930 .ca_mode = S_IRUGO | S_IRUSR }, 1931 .show = o2hb_region_pid_read, 1932 }; 1933 1934 static struct configfs_attribute *o2hb_region_attrs[] = { 1935 &o2hb_region_attr_block_bytes.attr, 1936 &o2hb_region_attr_start_block.attr, 1937 &o2hb_region_attr_blocks.attr, 1938 &o2hb_region_attr_dev.attr, 1939 &o2hb_region_attr_pid.attr, 1940 NULL, 1941 }; 1942 1943 static ssize_t o2hb_region_show(struct config_item *item, 1944 struct configfs_attribute *attr, 1945 char *page) 1946 { 1947 struct o2hb_region *reg = to_o2hb_region(item); 1948 struct o2hb_region_attribute *o2hb_region_attr = 1949 container_of(attr, struct o2hb_region_attribute, attr); 1950 ssize_t ret = 0; 1951 1952 if (o2hb_region_attr->show) 1953 ret = o2hb_region_attr->show(reg, page); 1954 return ret; 1955 } 1956 1957 static ssize_t o2hb_region_store(struct config_item *item, 1958 struct configfs_attribute *attr, 1959 const char *page, size_t count) 1960 { 1961 struct o2hb_region *reg = to_o2hb_region(item); 1962 struct o2hb_region_attribute *o2hb_region_attr = 1963 container_of(attr, struct o2hb_region_attribute, attr); 1964 ssize_t ret = -EINVAL; 1965 1966 if (o2hb_region_attr->store) 1967 ret = o2hb_region_attr->store(reg, page, count); 1968 return ret; 1969 } 1970 1971 static struct configfs_item_operations o2hb_region_item_ops = { 1972 .release = o2hb_region_release, 1973 .show_attribute = o2hb_region_show, 1974 .store_attribute = o2hb_region_store, 1975 }; 1976 1977 static struct config_item_type o2hb_region_type = { 1978 .ct_item_ops = &o2hb_region_item_ops, 1979 .ct_attrs = o2hb_region_attrs, 1980 .ct_owner = THIS_MODULE, 1981 }; 1982 1983 /* heartbeat set */ 1984 1985 struct o2hb_heartbeat_group { 1986 struct config_group hs_group; 1987 /* some stuff? */ 1988 }; 1989 1990 static struct o2hb_heartbeat_group *to_o2hb_heartbeat_group(struct config_group *group) 1991 { 1992 return group ? 1993 container_of(group, struct o2hb_heartbeat_group, hs_group) 1994 : NULL; 1995 } 1996 1997 static int o2hb_debug_region_init(struct o2hb_region *reg, struct dentry *dir) 1998 { 1999 int ret = -ENOMEM; 2000 2001 reg->hr_debug_dir = 2002 debugfs_create_dir(config_item_name(®->hr_item), dir); 2003 if (!reg->hr_debug_dir) { 2004 mlog_errno(ret); 2005 goto bail; 2006 } 2007 2008 reg->hr_debug_livenodes = 2009 o2hb_debug_create(O2HB_DEBUG_LIVENODES, 2010 reg->hr_debug_dir, 2011 &(reg->hr_db_livenodes), 2012 sizeof(*(reg->hr_db_livenodes)), 2013 O2HB_DB_TYPE_REGION_LIVENODES, 2014 sizeof(reg->hr_live_node_bitmap), 2015 O2NM_MAX_NODES, reg); 2016 if (!reg->hr_debug_livenodes) { 2017 mlog_errno(ret); 2018 goto bail; 2019 } 2020 2021 reg->hr_debug_regnum = 2022 o2hb_debug_create(O2HB_DEBUG_REGION_NUMBER, 2023 reg->hr_debug_dir, 2024 &(reg->hr_db_regnum), 2025 sizeof(*(reg->hr_db_regnum)), 2026 O2HB_DB_TYPE_REGION_NUMBER, 2027 0, O2NM_MAX_NODES, reg); 2028 if (!reg->hr_debug_regnum) { 2029 mlog_errno(ret); 2030 goto bail; 2031 } 2032 2033 reg->hr_debug_elapsed_time = 2034 o2hb_debug_create(O2HB_DEBUG_REGION_ELAPSED_TIME, 2035 reg->hr_debug_dir, 2036 &(reg->hr_db_elapsed_time), 2037 sizeof(*(reg->hr_db_elapsed_time)), 2038 O2HB_DB_TYPE_REGION_ELAPSED_TIME, 2039 0, 0, reg); 2040 if (!reg->hr_debug_elapsed_time) { 2041 mlog_errno(ret); 2042 goto bail; 2043 } 2044 2045 reg->hr_debug_pinned = 2046 o2hb_debug_create(O2HB_DEBUG_REGION_PINNED, 2047 reg->hr_debug_dir, 2048 &(reg->hr_db_pinned), 2049 sizeof(*(reg->hr_db_pinned)), 2050 O2HB_DB_TYPE_REGION_PINNED, 2051 0, 0, reg); 2052 if (!reg->hr_debug_pinned) { 2053 mlog_errno(ret); 2054 goto bail; 2055 } 2056 2057 ret = 0; 2058 bail: 2059 return ret; 2060 } 2061 2062 static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *group, 2063 const char *name) 2064 { 2065 struct o2hb_region *reg = NULL; 2066 int ret; 2067 2068 reg = kzalloc(sizeof(struct o2hb_region), GFP_KERNEL); 2069 if (reg == NULL) 2070 return ERR_PTR(-ENOMEM); 2071 2072 if (strlen(name) > O2HB_MAX_REGION_NAME_LEN) { 2073 ret = -ENAMETOOLONG; 2074 goto free; 2075 } 2076 2077 spin_lock(&o2hb_live_lock); 2078 reg->hr_region_num = 0; 2079 if (o2hb_global_heartbeat_active()) { 2080 reg->hr_region_num = find_first_zero_bit(o2hb_region_bitmap, 2081 O2NM_MAX_REGIONS); 2082 if (reg->hr_region_num >= O2NM_MAX_REGIONS) { 2083 spin_unlock(&o2hb_live_lock); 2084 ret = -EFBIG; 2085 goto free; 2086 } 2087 set_bit(reg->hr_region_num, o2hb_region_bitmap); 2088 } 2089 list_add_tail(®->hr_all_item, &o2hb_all_regions); 2090 spin_unlock(&o2hb_live_lock); 2091 2092 config_item_init_type_name(®->hr_item, name, &o2hb_region_type); 2093 2094 ret = o2hb_debug_region_init(reg, o2hb_debug_dir); 2095 if (ret) { 2096 config_item_put(®->hr_item); 2097 goto free; 2098 } 2099 2100 return ®->hr_item; 2101 free: 2102 kfree(reg); 2103 return ERR_PTR(ret); 2104 } 2105 2106 static void o2hb_heartbeat_group_drop_item(struct config_group *group, 2107 struct config_item *item) 2108 { 2109 struct task_struct *hb_task; 2110 struct o2hb_region *reg = to_o2hb_region(item); 2111 int quorum_region = 0; 2112 2113 /* stop the thread when the user removes the region dir */ 2114 spin_lock(&o2hb_live_lock); 2115 hb_task = reg->hr_task; 2116 reg->hr_task = NULL; 2117 reg->hr_item_dropped = 1; 2118 spin_unlock(&o2hb_live_lock); 2119 2120 if (hb_task) 2121 kthread_stop(hb_task); 2122 2123 if (o2hb_global_heartbeat_active()) { 2124 spin_lock(&o2hb_live_lock); 2125 clear_bit(reg->hr_region_num, o2hb_region_bitmap); 2126 clear_bit(reg->hr_region_num, o2hb_live_region_bitmap); 2127 if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap)) 2128 quorum_region = 1; 2129 clear_bit(reg->hr_region_num, o2hb_quorum_region_bitmap); 2130 spin_unlock(&o2hb_live_lock); 2131 printk(KERN_NOTICE "o2hb: Heartbeat %s on region %s (%s)\n", 2132 ((atomic_read(®->hr_steady_iterations) == 0) ? 2133 "stopped" : "start aborted"), config_item_name(item), 2134 reg->hr_dev_name); 2135 } 2136 2137 /* 2138 * If we're racing a dev_write(), we need to wake them. They will 2139 * check reg->hr_task 2140 */ 2141 if (atomic_read(®->hr_steady_iterations) != 0) { 2142 reg->hr_aborted_start = 1; 2143 atomic_set(®->hr_steady_iterations, 0); 2144 wake_up(&o2hb_steady_queue); 2145 } 2146 2147 config_item_put(item); 2148 2149 if (!o2hb_global_heartbeat_active() || !quorum_region) 2150 return; 2151 2152 /* 2153 * If global heartbeat active and there are dependent users, 2154 * pin all regions if quorum region count <= CUT_OFF 2155 */ 2156 spin_lock(&o2hb_live_lock); 2157 2158 if (!o2hb_dependent_users) 2159 goto unlock; 2160 2161 if (bitmap_weight(o2hb_quorum_region_bitmap, 2162 O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF) 2163 o2hb_region_pin(NULL); 2164 2165 unlock: 2166 spin_unlock(&o2hb_live_lock); 2167 } 2168 2169 struct o2hb_heartbeat_group_attribute { 2170 struct configfs_attribute attr; 2171 ssize_t (*show)(struct o2hb_heartbeat_group *, char *); 2172 ssize_t (*store)(struct o2hb_heartbeat_group *, const char *, size_t); 2173 }; 2174 2175 static ssize_t o2hb_heartbeat_group_show(struct config_item *item, 2176 struct configfs_attribute *attr, 2177 char *page) 2178 { 2179 struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item)); 2180 struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr = 2181 container_of(attr, struct o2hb_heartbeat_group_attribute, attr); 2182 ssize_t ret = 0; 2183 2184 if (o2hb_heartbeat_group_attr->show) 2185 ret = o2hb_heartbeat_group_attr->show(reg, page); 2186 return ret; 2187 } 2188 2189 static ssize_t o2hb_heartbeat_group_store(struct config_item *item, 2190 struct configfs_attribute *attr, 2191 const char *page, size_t count) 2192 { 2193 struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item)); 2194 struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr = 2195 container_of(attr, struct o2hb_heartbeat_group_attribute, attr); 2196 ssize_t ret = -EINVAL; 2197 2198 if (o2hb_heartbeat_group_attr->store) 2199 ret = o2hb_heartbeat_group_attr->store(reg, page, count); 2200 return ret; 2201 } 2202 2203 static ssize_t o2hb_heartbeat_group_threshold_show(struct o2hb_heartbeat_group *group, 2204 char *page) 2205 { 2206 return sprintf(page, "%u\n", o2hb_dead_threshold); 2207 } 2208 2209 static ssize_t o2hb_heartbeat_group_threshold_store(struct o2hb_heartbeat_group *group, 2210 const char *page, 2211 size_t count) 2212 { 2213 unsigned long tmp; 2214 char *p = (char *)page; 2215 2216 tmp = simple_strtoul(p, &p, 10); 2217 if (!p || (*p && (*p != '\n'))) 2218 return -EINVAL; 2219 2220 /* this will validate ranges for us. */ 2221 o2hb_dead_threshold_set((unsigned int) tmp); 2222 2223 return count; 2224 } 2225 2226 static 2227 ssize_t o2hb_heartbeat_group_mode_show(struct o2hb_heartbeat_group *group, 2228 char *page) 2229 { 2230 return sprintf(page, "%s\n", 2231 o2hb_heartbeat_mode_desc[o2hb_heartbeat_mode]); 2232 } 2233 2234 static 2235 ssize_t o2hb_heartbeat_group_mode_store(struct o2hb_heartbeat_group *group, 2236 const char *page, size_t count) 2237 { 2238 unsigned int i; 2239 int ret; 2240 size_t len; 2241 2242 len = (page[count - 1] == '\n') ? count - 1 : count; 2243 if (!len) 2244 return -EINVAL; 2245 2246 for (i = 0; i < O2HB_HEARTBEAT_NUM_MODES; ++i) { 2247 if (strnicmp(page, o2hb_heartbeat_mode_desc[i], len)) 2248 continue; 2249 2250 ret = o2hb_global_heartbeat_mode_set(i); 2251 if (!ret) 2252 printk(KERN_NOTICE "o2hb: Heartbeat mode set to %s\n", 2253 o2hb_heartbeat_mode_desc[i]); 2254 return count; 2255 } 2256 2257 return -EINVAL; 2258 2259 } 2260 2261 static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_threshold = { 2262 .attr = { .ca_owner = THIS_MODULE, 2263 .ca_name = "dead_threshold", 2264 .ca_mode = S_IRUGO | S_IWUSR }, 2265 .show = o2hb_heartbeat_group_threshold_show, 2266 .store = o2hb_heartbeat_group_threshold_store, 2267 }; 2268 2269 static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_mode = { 2270 .attr = { .ca_owner = THIS_MODULE, 2271 .ca_name = "mode", 2272 .ca_mode = S_IRUGO | S_IWUSR }, 2273 .show = o2hb_heartbeat_group_mode_show, 2274 .store = o2hb_heartbeat_group_mode_store, 2275 }; 2276 2277 static struct configfs_attribute *o2hb_heartbeat_group_attrs[] = { 2278 &o2hb_heartbeat_group_attr_threshold.attr, 2279 &o2hb_heartbeat_group_attr_mode.attr, 2280 NULL, 2281 }; 2282 2283 static struct configfs_item_operations o2hb_heartbeat_group_item_ops = { 2284 .show_attribute = o2hb_heartbeat_group_show, 2285 .store_attribute = o2hb_heartbeat_group_store, 2286 }; 2287 2288 static struct configfs_group_operations o2hb_heartbeat_group_group_ops = { 2289 .make_item = o2hb_heartbeat_group_make_item, 2290 .drop_item = o2hb_heartbeat_group_drop_item, 2291 }; 2292 2293 static struct config_item_type o2hb_heartbeat_group_type = { 2294 .ct_group_ops = &o2hb_heartbeat_group_group_ops, 2295 .ct_item_ops = &o2hb_heartbeat_group_item_ops, 2296 .ct_attrs = o2hb_heartbeat_group_attrs, 2297 .ct_owner = THIS_MODULE, 2298 }; 2299 2300 /* this is just here to avoid touching group in heartbeat.h which the 2301 * entire damn world #includes */ 2302 struct config_group *o2hb_alloc_hb_set(void) 2303 { 2304 struct o2hb_heartbeat_group *hs = NULL; 2305 struct config_group *ret = NULL; 2306 2307 hs = kzalloc(sizeof(struct o2hb_heartbeat_group), GFP_KERNEL); 2308 if (hs == NULL) 2309 goto out; 2310 2311 config_group_init_type_name(&hs->hs_group, "heartbeat", 2312 &o2hb_heartbeat_group_type); 2313 2314 ret = &hs->hs_group; 2315 out: 2316 if (ret == NULL) 2317 kfree(hs); 2318 return ret; 2319 } 2320 2321 void o2hb_free_hb_set(struct config_group *group) 2322 { 2323 struct o2hb_heartbeat_group *hs = to_o2hb_heartbeat_group(group); 2324 kfree(hs); 2325 } 2326 2327 /* hb callback registration and issuing */ 2328 2329 static struct o2hb_callback *hbcall_from_type(enum o2hb_callback_type type) 2330 { 2331 if (type == O2HB_NUM_CB) 2332 return ERR_PTR(-EINVAL); 2333 2334 return &o2hb_callbacks[type]; 2335 } 2336 2337 void o2hb_setup_callback(struct o2hb_callback_func *hc, 2338 enum o2hb_callback_type type, 2339 o2hb_cb_func *func, 2340 void *data, 2341 int priority) 2342 { 2343 INIT_LIST_HEAD(&hc->hc_item); 2344 hc->hc_func = func; 2345 hc->hc_data = data; 2346 hc->hc_priority = priority; 2347 hc->hc_type = type; 2348 hc->hc_magic = O2HB_CB_MAGIC; 2349 } 2350 EXPORT_SYMBOL_GPL(o2hb_setup_callback); 2351 2352 /* 2353 * In local heartbeat mode, region_uuid passed matches the dlm domain name. 2354 * In global heartbeat mode, region_uuid passed is NULL. 2355 * 2356 * In local, we only pin the matching region. In global we pin all the active 2357 * regions. 2358 */ 2359 static int o2hb_region_pin(const char *region_uuid) 2360 { 2361 int ret = 0, found = 0; 2362 struct o2hb_region *reg; 2363 char *uuid; 2364 2365 assert_spin_locked(&o2hb_live_lock); 2366 2367 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) { 2368 if (reg->hr_item_dropped) 2369 continue; 2370 2371 uuid = config_item_name(®->hr_item); 2372 2373 /* local heartbeat */ 2374 if (region_uuid) { 2375 if (strcmp(region_uuid, uuid)) 2376 continue; 2377 found = 1; 2378 } 2379 2380 if (reg->hr_item_pinned || reg->hr_item_dropped) 2381 goto skip_pin; 2382 2383 /* Ignore ENOENT only for local hb (userdlm domain) */ 2384 ret = o2nm_depend_item(®->hr_item); 2385 if (!ret) { 2386 mlog(ML_CLUSTER, "Pin region %s\n", uuid); 2387 reg->hr_item_pinned = 1; 2388 } else { 2389 if (ret == -ENOENT && found) 2390 ret = 0; 2391 else { 2392 mlog(ML_ERROR, "Pin region %s fails with %d\n", 2393 uuid, ret); 2394 break; 2395 } 2396 } 2397 skip_pin: 2398 if (found) 2399 break; 2400 } 2401 2402 return ret; 2403 } 2404 2405 /* 2406 * In local heartbeat mode, region_uuid passed matches the dlm domain name. 2407 * In global heartbeat mode, region_uuid passed is NULL. 2408 * 2409 * In local, we only unpin the matching region. In global we unpin all the 2410 * active regions. 2411 */ 2412 static void o2hb_region_unpin(const char *region_uuid) 2413 { 2414 struct o2hb_region *reg; 2415 char *uuid; 2416 int found = 0; 2417 2418 assert_spin_locked(&o2hb_live_lock); 2419 2420 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) { 2421 if (reg->hr_item_dropped) 2422 continue; 2423 2424 uuid = config_item_name(®->hr_item); 2425 if (region_uuid) { 2426 if (strcmp(region_uuid, uuid)) 2427 continue; 2428 found = 1; 2429 } 2430 2431 if (reg->hr_item_pinned) { 2432 mlog(ML_CLUSTER, "Unpin region %s\n", uuid); 2433 o2nm_undepend_item(®->hr_item); 2434 reg->hr_item_pinned = 0; 2435 } 2436 if (found) 2437 break; 2438 } 2439 } 2440 2441 static int o2hb_region_inc_user(const char *region_uuid) 2442 { 2443 int ret = 0; 2444 2445 spin_lock(&o2hb_live_lock); 2446 2447 /* local heartbeat */ 2448 if (!o2hb_global_heartbeat_active()) { 2449 ret = o2hb_region_pin(region_uuid); 2450 goto unlock; 2451 } 2452 2453 /* 2454 * if global heartbeat active and this is the first dependent user, 2455 * pin all regions if quorum region count <= CUT_OFF 2456 */ 2457 o2hb_dependent_users++; 2458 if (o2hb_dependent_users > 1) 2459 goto unlock; 2460 2461 if (bitmap_weight(o2hb_quorum_region_bitmap, 2462 O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF) 2463 ret = o2hb_region_pin(NULL); 2464 2465 unlock: 2466 spin_unlock(&o2hb_live_lock); 2467 return ret; 2468 } 2469 2470 void o2hb_region_dec_user(const char *region_uuid) 2471 { 2472 spin_lock(&o2hb_live_lock); 2473 2474 /* local heartbeat */ 2475 if (!o2hb_global_heartbeat_active()) { 2476 o2hb_region_unpin(region_uuid); 2477 goto unlock; 2478 } 2479 2480 /* 2481 * if global heartbeat active and there are no dependent users, 2482 * unpin all quorum regions 2483 */ 2484 o2hb_dependent_users--; 2485 if (!o2hb_dependent_users) 2486 o2hb_region_unpin(NULL); 2487 2488 unlock: 2489 spin_unlock(&o2hb_live_lock); 2490 } 2491 2492 int o2hb_register_callback(const char *region_uuid, 2493 struct o2hb_callback_func *hc) 2494 { 2495 struct o2hb_callback_func *f; 2496 struct o2hb_callback *hbcall; 2497 int ret; 2498 2499 BUG_ON(hc->hc_magic != O2HB_CB_MAGIC); 2500 BUG_ON(!list_empty(&hc->hc_item)); 2501 2502 hbcall = hbcall_from_type(hc->hc_type); 2503 if (IS_ERR(hbcall)) { 2504 ret = PTR_ERR(hbcall); 2505 goto out; 2506 } 2507 2508 if (region_uuid) { 2509 ret = o2hb_region_inc_user(region_uuid); 2510 if (ret) { 2511 mlog_errno(ret); 2512 goto out; 2513 } 2514 } 2515 2516 down_write(&o2hb_callback_sem); 2517 2518 list_for_each_entry(f, &hbcall->list, hc_item) { 2519 if (hc->hc_priority < f->hc_priority) { 2520 list_add_tail(&hc->hc_item, &f->hc_item); 2521 break; 2522 } 2523 } 2524 if (list_empty(&hc->hc_item)) 2525 list_add_tail(&hc->hc_item, &hbcall->list); 2526 2527 up_write(&o2hb_callback_sem); 2528 ret = 0; 2529 out: 2530 mlog(ML_CLUSTER, "returning %d on behalf of %p for funcs %p\n", 2531 ret, __builtin_return_address(0), hc); 2532 return ret; 2533 } 2534 EXPORT_SYMBOL_GPL(o2hb_register_callback); 2535 2536 void o2hb_unregister_callback(const char *region_uuid, 2537 struct o2hb_callback_func *hc) 2538 { 2539 BUG_ON(hc->hc_magic != O2HB_CB_MAGIC); 2540 2541 mlog(ML_CLUSTER, "on behalf of %p for funcs %p\n", 2542 __builtin_return_address(0), hc); 2543 2544 /* XXX Can this happen _with_ a region reference? */ 2545 if (list_empty(&hc->hc_item)) 2546 return; 2547 2548 if (region_uuid) 2549 o2hb_region_dec_user(region_uuid); 2550 2551 down_write(&o2hb_callback_sem); 2552 2553 list_del_init(&hc->hc_item); 2554 2555 up_write(&o2hb_callback_sem); 2556 } 2557 EXPORT_SYMBOL_GPL(o2hb_unregister_callback); 2558 2559 int o2hb_check_node_heartbeating(u8 node_num) 2560 { 2561 unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; 2562 2563 o2hb_fill_node_map(testing_map, sizeof(testing_map)); 2564 if (!test_bit(node_num, testing_map)) { 2565 mlog(ML_HEARTBEAT, 2566 "node (%u) does not have heartbeating enabled.\n", 2567 node_num); 2568 return 0; 2569 } 2570 2571 return 1; 2572 } 2573 EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating); 2574 2575 int o2hb_check_node_heartbeating_from_callback(u8 node_num) 2576 { 2577 unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; 2578 2579 o2hb_fill_node_map_from_callback(testing_map, sizeof(testing_map)); 2580 if (!test_bit(node_num, testing_map)) { 2581 mlog(ML_HEARTBEAT, 2582 "node (%u) does not have heartbeating enabled.\n", 2583 node_num); 2584 return 0; 2585 } 2586 2587 return 1; 2588 } 2589 EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating_from_callback); 2590 2591 /* Makes sure our local node is configured with a node number, and is 2592 * heartbeating. */ 2593 int o2hb_check_local_node_heartbeating(void) 2594 { 2595 u8 node_num; 2596 2597 /* if this node was set then we have networking */ 2598 node_num = o2nm_this_node(); 2599 if (node_num == O2NM_MAX_NODES) { 2600 mlog(ML_HEARTBEAT, "this node has not been configured.\n"); 2601 return 0; 2602 } 2603 2604 return o2hb_check_node_heartbeating(node_num); 2605 } 2606 EXPORT_SYMBOL_GPL(o2hb_check_local_node_heartbeating); 2607 2608 /* 2609 * this is just a hack until we get the plumbing which flips file systems 2610 * read only and drops the hb ref instead of killing the node dead. 2611 */ 2612 void o2hb_stop_all_regions(void) 2613 { 2614 struct o2hb_region *reg; 2615 2616 mlog(ML_ERROR, "stopping heartbeat on all active regions.\n"); 2617 2618 spin_lock(&o2hb_live_lock); 2619 2620 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) 2621 reg->hr_unclean_stop = 1; 2622 2623 spin_unlock(&o2hb_live_lock); 2624 } 2625 EXPORT_SYMBOL_GPL(o2hb_stop_all_regions); 2626 2627 int o2hb_get_all_regions(char *region_uuids, u8 max_regions) 2628 { 2629 struct o2hb_region *reg; 2630 int numregs = 0; 2631 char *p; 2632 2633 spin_lock(&o2hb_live_lock); 2634 2635 p = region_uuids; 2636 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) { 2637 if (reg->hr_item_dropped) 2638 continue; 2639 2640 mlog(0, "Region: %s\n", config_item_name(®->hr_item)); 2641 if (numregs < max_regions) { 2642 memcpy(p, config_item_name(®->hr_item), 2643 O2HB_MAX_REGION_NAME_LEN); 2644 p += O2HB_MAX_REGION_NAME_LEN; 2645 } 2646 numregs++; 2647 } 2648 2649 spin_unlock(&o2hb_live_lock); 2650 2651 return numregs; 2652 } 2653 EXPORT_SYMBOL_GPL(o2hb_get_all_regions); 2654 2655 int o2hb_global_heartbeat_active(void) 2656 { 2657 return (o2hb_heartbeat_mode == O2HB_HEARTBEAT_GLOBAL); 2658 } 2659 EXPORT_SYMBOL(o2hb_global_heartbeat_active); 2660