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, ret = %d\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, ret); 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 (IS_ERR_OR_NULL(o2hb_debug_dir)) { 1316 ret = o2hb_debug_dir ? 1317 PTR_ERR(o2hb_debug_dir) : -ENOMEM; 1318 mlog_errno(ret); 1319 goto bail; 1320 } 1321 1322 o2hb_debug_livenodes = o2hb_debug_create(O2HB_DEBUG_LIVENODES, 1323 o2hb_debug_dir, 1324 &o2hb_db_livenodes, 1325 sizeof(*o2hb_db_livenodes), 1326 O2HB_DB_TYPE_LIVENODES, 1327 sizeof(o2hb_live_node_bitmap), 1328 O2NM_MAX_NODES, 1329 o2hb_live_node_bitmap); 1330 if (IS_ERR_OR_NULL(o2hb_debug_livenodes)) { 1331 ret = o2hb_debug_livenodes ? 1332 PTR_ERR(o2hb_debug_livenodes) : -ENOMEM; 1333 mlog_errno(ret); 1334 goto bail; 1335 } 1336 1337 o2hb_debug_liveregions = o2hb_debug_create(O2HB_DEBUG_LIVEREGIONS, 1338 o2hb_debug_dir, 1339 &o2hb_db_liveregions, 1340 sizeof(*o2hb_db_liveregions), 1341 O2HB_DB_TYPE_LIVEREGIONS, 1342 sizeof(o2hb_live_region_bitmap), 1343 O2NM_MAX_REGIONS, 1344 o2hb_live_region_bitmap); 1345 if (IS_ERR_OR_NULL(o2hb_debug_liveregions)) { 1346 ret = o2hb_debug_liveregions ? 1347 PTR_ERR(o2hb_debug_liveregions) : -ENOMEM; 1348 mlog_errno(ret); 1349 goto bail; 1350 } 1351 1352 o2hb_debug_quorumregions = 1353 o2hb_debug_create(O2HB_DEBUG_QUORUMREGIONS, 1354 o2hb_debug_dir, 1355 &o2hb_db_quorumregions, 1356 sizeof(*o2hb_db_quorumregions), 1357 O2HB_DB_TYPE_QUORUMREGIONS, 1358 sizeof(o2hb_quorum_region_bitmap), 1359 O2NM_MAX_REGIONS, 1360 o2hb_quorum_region_bitmap); 1361 if (IS_ERR_OR_NULL(o2hb_debug_quorumregions)) { 1362 ret = o2hb_debug_quorumregions ? 1363 PTR_ERR(o2hb_debug_quorumregions) : -ENOMEM; 1364 mlog_errno(ret); 1365 goto bail; 1366 } 1367 1368 o2hb_debug_failedregions = 1369 o2hb_debug_create(O2HB_DEBUG_FAILEDREGIONS, 1370 o2hb_debug_dir, 1371 &o2hb_db_failedregions, 1372 sizeof(*o2hb_db_failedregions), 1373 O2HB_DB_TYPE_FAILEDREGIONS, 1374 sizeof(o2hb_failed_region_bitmap), 1375 O2NM_MAX_REGIONS, 1376 o2hb_failed_region_bitmap); 1377 if (IS_ERR_OR_NULL(o2hb_debug_failedregions)) { 1378 ret = o2hb_debug_failedregions ? 1379 PTR_ERR(o2hb_debug_failedregions) : -ENOMEM; 1380 mlog_errno(ret); 1381 goto bail; 1382 } 1383 1384 ret = 0; 1385 bail: 1386 if (ret) 1387 o2hb_exit(); 1388 1389 return ret; 1390 } 1391 1392 int o2hb_init(void) 1393 { 1394 int i; 1395 1396 for (i = 0; i < ARRAY_SIZE(o2hb_callbacks); i++) 1397 INIT_LIST_HEAD(&o2hb_callbacks[i].list); 1398 1399 for (i = 0; i < ARRAY_SIZE(o2hb_live_slots); i++) 1400 INIT_LIST_HEAD(&o2hb_live_slots[i]); 1401 1402 INIT_LIST_HEAD(&o2hb_node_events); 1403 1404 memset(o2hb_live_node_bitmap, 0, sizeof(o2hb_live_node_bitmap)); 1405 memset(o2hb_region_bitmap, 0, sizeof(o2hb_region_bitmap)); 1406 memset(o2hb_live_region_bitmap, 0, sizeof(o2hb_live_region_bitmap)); 1407 memset(o2hb_quorum_region_bitmap, 0, sizeof(o2hb_quorum_region_bitmap)); 1408 memset(o2hb_failed_region_bitmap, 0, sizeof(o2hb_failed_region_bitmap)); 1409 1410 o2hb_dependent_users = 0; 1411 1412 return o2hb_debug_init(); 1413 } 1414 1415 /* if we're already in a callback then we're already serialized by the sem */ 1416 static void o2hb_fill_node_map_from_callback(unsigned long *map, 1417 unsigned bytes) 1418 { 1419 BUG_ON(bytes < (BITS_TO_LONGS(O2NM_MAX_NODES) * sizeof(unsigned long))); 1420 1421 memcpy(map, &o2hb_live_node_bitmap, bytes); 1422 } 1423 1424 /* 1425 * get a map of all nodes that are heartbeating in any regions 1426 */ 1427 void o2hb_fill_node_map(unsigned long *map, unsigned bytes) 1428 { 1429 /* callers want to serialize this map and callbacks so that they 1430 * can trust that they don't miss nodes coming to the party */ 1431 down_read(&o2hb_callback_sem); 1432 spin_lock(&o2hb_live_lock); 1433 o2hb_fill_node_map_from_callback(map, bytes); 1434 spin_unlock(&o2hb_live_lock); 1435 up_read(&o2hb_callback_sem); 1436 } 1437 EXPORT_SYMBOL_GPL(o2hb_fill_node_map); 1438 1439 /* 1440 * heartbeat configfs bits. The heartbeat set is a default set under 1441 * the cluster set in nodemanager.c. 1442 */ 1443 1444 static struct o2hb_region *to_o2hb_region(struct config_item *item) 1445 { 1446 return item ? container_of(item, struct o2hb_region, hr_item) : NULL; 1447 } 1448 1449 /* drop_item only drops its ref after killing the thread, nothing should 1450 * be using the region anymore. this has to clean up any state that 1451 * attributes might have built up. */ 1452 static void o2hb_region_release(struct config_item *item) 1453 { 1454 int i; 1455 struct page *page; 1456 struct o2hb_region *reg = to_o2hb_region(item); 1457 1458 mlog(ML_HEARTBEAT, "hb region release (%s)\n", reg->hr_dev_name); 1459 1460 kfree(reg->hr_tmp_block); 1461 1462 if (reg->hr_slot_data) { 1463 for (i = 0; i < reg->hr_num_pages; i++) { 1464 page = reg->hr_slot_data[i]; 1465 if (page) 1466 __free_page(page); 1467 } 1468 kfree(reg->hr_slot_data); 1469 } 1470 1471 if (reg->hr_bdev) 1472 blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE); 1473 1474 kfree(reg->hr_slots); 1475 1476 kfree(reg->hr_db_regnum); 1477 kfree(reg->hr_db_livenodes); 1478 debugfs_remove(reg->hr_debug_livenodes); 1479 debugfs_remove(reg->hr_debug_regnum); 1480 debugfs_remove(reg->hr_debug_elapsed_time); 1481 debugfs_remove(reg->hr_debug_pinned); 1482 debugfs_remove(reg->hr_debug_dir); 1483 1484 spin_lock(&o2hb_live_lock); 1485 list_del(®->hr_all_item); 1486 spin_unlock(&o2hb_live_lock); 1487 1488 kfree(reg); 1489 } 1490 1491 static int o2hb_read_block_input(struct o2hb_region *reg, 1492 const char *page, 1493 size_t count, 1494 unsigned long *ret_bytes, 1495 unsigned int *ret_bits) 1496 { 1497 unsigned long bytes; 1498 char *p = (char *)page; 1499 1500 bytes = simple_strtoul(p, &p, 0); 1501 if (!p || (*p && (*p != '\n'))) 1502 return -EINVAL; 1503 1504 /* Heartbeat and fs min / max block sizes are the same. */ 1505 if (bytes > 4096 || bytes < 512) 1506 return -ERANGE; 1507 if (hweight16(bytes) != 1) 1508 return -EINVAL; 1509 1510 if (ret_bytes) 1511 *ret_bytes = bytes; 1512 if (ret_bits) 1513 *ret_bits = ffs(bytes) - 1; 1514 1515 return 0; 1516 } 1517 1518 static ssize_t o2hb_region_block_bytes_read(struct o2hb_region *reg, 1519 char *page) 1520 { 1521 return sprintf(page, "%u\n", reg->hr_block_bytes); 1522 } 1523 1524 static ssize_t o2hb_region_block_bytes_write(struct o2hb_region *reg, 1525 const char *page, 1526 size_t count) 1527 { 1528 int status; 1529 unsigned long block_bytes; 1530 unsigned int block_bits; 1531 1532 if (reg->hr_bdev) 1533 return -EINVAL; 1534 1535 status = o2hb_read_block_input(reg, page, count, 1536 &block_bytes, &block_bits); 1537 if (status) 1538 return status; 1539 1540 reg->hr_block_bytes = (unsigned int)block_bytes; 1541 reg->hr_block_bits = block_bits; 1542 1543 return count; 1544 } 1545 1546 static ssize_t o2hb_region_start_block_read(struct o2hb_region *reg, 1547 char *page) 1548 { 1549 return sprintf(page, "%llu\n", reg->hr_start_block); 1550 } 1551 1552 static ssize_t o2hb_region_start_block_write(struct o2hb_region *reg, 1553 const char *page, 1554 size_t count) 1555 { 1556 unsigned long long tmp; 1557 char *p = (char *)page; 1558 1559 if (reg->hr_bdev) 1560 return -EINVAL; 1561 1562 tmp = simple_strtoull(p, &p, 0); 1563 if (!p || (*p && (*p != '\n'))) 1564 return -EINVAL; 1565 1566 reg->hr_start_block = tmp; 1567 1568 return count; 1569 } 1570 1571 static ssize_t o2hb_region_blocks_read(struct o2hb_region *reg, 1572 char *page) 1573 { 1574 return sprintf(page, "%d\n", reg->hr_blocks); 1575 } 1576 1577 static ssize_t o2hb_region_blocks_write(struct o2hb_region *reg, 1578 const char *page, 1579 size_t count) 1580 { 1581 unsigned long tmp; 1582 char *p = (char *)page; 1583 1584 if (reg->hr_bdev) 1585 return -EINVAL; 1586 1587 tmp = simple_strtoul(p, &p, 0); 1588 if (!p || (*p && (*p != '\n'))) 1589 return -EINVAL; 1590 1591 if (tmp > O2NM_MAX_NODES || tmp == 0) 1592 return -ERANGE; 1593 1594 reg->hr_blocks = (unsigned int)tmp; 1595 1596 return count; 1597 } 1598 1599 static ssize_t o2hb_region_dev_read(struct o2hb_region *reg, 1600 char *page) 1601 { 1602 unsigned int ret = 0; 1603 1604 if (reg->hr_bdev) 1605 ret = sprintf(page, "%s\n", reg->hr_dev_name); 1606 1607 return ret; 1608 } 1609 1610 static void o2hb_init_region_params(struct o2hb_region *reg) 1611 { 1612 reg->hr_slots_per_page = PAGE_CACHE_SIZE >> reg->hr_block_bits; 1613 reg->hr_timeout_ms = O2HB_REGION_TIMEOUT_MS; 1614 1615 mlog(ML_HEARTBEAT, "hr_start_block = %llu, hr_blocks = %u\n", 1616 reg->hr_start_block, reg->hr_blocks); 1617 mlog(ML_HEARTBEAT, "hr_block_bytes = %u, hr_block_bits = %u\n", 1618 reg->hr_block_bytes, reg->hr_block_bits); 1619 mlog(ML_HEARTBEAT, "hr_timeout_ms = %u\n", reg->hr_timeout_ms); 1620 mlog(ML_HEARTBEAT, "dead threshold = %u\n", o2hb_dead_threshold); 1621 } 1622 1623 static int o2hb_map_slot_data(struct o2hb_region *reg) 1624 { 1625 int i, j; 1626 unsigned int last_slot; 1627 unsigned int spp = reg->hr_slots_per_page; 1628 struct page *page; 1629 char *raw; 1630 struct o2hb_disk_slot *slot; 1631 1632 reg->hr_tmp_block = kmalloc(reg->hr_block_bytes, GFP_KERNEL); 1633 if (reg->hr_tmp_block == NULL) { 1634 mlog_errno(-ENOMEM); 1635 return -ENOMEM; 1636 } 1637 1638 reg->hr_slots = kcalloc(reg->hr_blocks, 1639 sizeof(struct o2hb_disk_slot), GFP_KERNEL); 1640 if (reg->hr_slots == NULL) { 1641 mlog_errno(-ENOMEM); 1642 return -ENOMEM; 1643 } 1644 1645 for(i = 0; i < reg->hr_blocks; i++) { 1646 slot = ®->hr_slots[i]; 1647 slot->ds_node_num = i; 1648 INIT_LIST_HEAD(&slot->ds_live_item); 1649 slot->ds_raw_block = NULL; 1650 } 1651 1652 reg->hr_num_pages = (reg->hr_blocks + spp - 1) / spp; 1653 mlog(ML_HEARTBEAT, "Going to require %u pages to cover %u blocks " 1654 "at %u blocks per page\n", 1655 reg->hr_num_pages, reg->hr_blocks, spp); 1656 1657 reg->hr_slot_data = kcalloc(reg->hr_num_pages, sizeof(struct page *), 1658 GFP_KERNEL); 1659 if (!reg->hr_slot_data) { 1660 mlog_errno(-ENOMEM); 1661 return -ENOMEM; 1662 } 1663 1664 for(i = 0; i < reg->hr_num_pages; i++) { 1665 page = alloc_page(GFP_KERNEL); 1666 if (!page) { 1667 mlog_errno(-ENOMEM); 1668 return -ENOMEM; 1669 } 1670 1671 reg->hr_slot_data[i] = page; 1672 1673 last_slot = i * spp; 1674 raw = page_address(page); 1675 for (j = 0; 1676 (j < spp) && ((j + last_slot) < reg->hr_blocks); 1677 j++) { 1678 BUG_ON((j + last_slot) >= reg->hr_blocks); 1679 1680 slot = ®->hr_slots[j + last_slot]; 1681 slot->ds_raw_block = 1682 (struct o2hb_disk_heartbeat_block *) raw; 1683 1684 raw += reg->hr_block_bytes; 1685 } 1686 } 1687 1688 return 0; 1689 } 1690 1691 /* Read in all the slots available and populate the tracking 1692 * structures so that we can start with a baseline idea of what's 1693 * there. */ 1694 static int o2hb_populate_slot_data(struct o2hb_region *reg) 1695 { 1696 int ret, i; 1697 struct o2hb_disk_slot *slot; 1698 struct o2hb_disk_heartbeat_block *hb_block; 1699 1700 ret = o2hb_read_slots(reg, reg->hr_blocks); 1701 if (ret) { 1702 mlog_errno(ret); 1703 goto out; 1704 } 1705 1706 /* We only want to get an idea of the values initially in each 1707 * slot, so we do no verification - o2hb_check_slot will 1708 * actually determine if each configured slot is valid and 1709 * whether any values have changed. */ 1710 for(i = 0; i < reg->hr_blocks; i++) { 1711 slot = ®->hr_slots[i]; 1712 hb_block = (struct o2hb_disk_heartbeat_block *) slot->ds_raw_block; 1713 1714 /* Only fill the values that o2hb_check_slot uses to 1715 * determine changing slots */ 1716 slot->ds_last_time = le64_to_cpu(hb_block->hb_seq); 1717 slot->ds_last_generation = le64_to_cpu(hb_block->hb_generation); 1718 } 1719 1720 out: 1721 return ret; 1722 } 1723 1724 /* this is acting as commit; we set up all of hr_bdev and hr_task or nothing */ 1725 static ssize_t o2hb_region_dev_write(struct o2hb_region *reg, 1726 const char *page, 1727 size_t count) 1728 { 1729 struct task_struct *hb_task; 1730 long fd; 1731 int sectsize; 1732 char *p = (char *)page; 1733 struct fd f; 1734 struct inode *inode; 1735 ssize_t ret = -EINVAL; 1736 int live_threshold; 1737 1738 if (reg->hr_bdev) 1739 goto out; 1740 1741 /* We can't heartbeat without having had our node number 1742 * configured yet. */ 1743 if (o2nm_this_node() == O2NM_MAX_NODES) 1744 goto out; 1745 1746 fd = simple_strtol(p, &p, 0); 1747 if (!p || (*p && (*p != '\n'))) 1748 goto out; 1749 1750 if (fd < 0 || fd >= INT_MAX) 1751 goto out; 1752 1753 f = fdget(fd); 1754 if (f.file == NULL) 1755 goto out; 1756 1757 if (reg->hr_blocks == 0 || reg->hr_start_block == 0 || 1758 reg->hr_block_bytes == 0) 1759 goto out2; 1760 1761 inode = igrab(f.file->f_mapping->host); 1762 if (inode == NULL) 1763 goto out2; 1764 1765 if (!S_ISBLK(inode->i_mode)) 1766 goto out3; 1767 1768 reg->hr_bdev = I_BDEV(f.file->f_mapping->host); 1769 ret = blkdev_get(reg->hr_bdev, FMODE_WRITE | FMODE_READ, NULL); 1770 if (ret) { 1771 reg->hr_bdev = NULL; 1772 goto out3; 1773 } 1774 inode = NULL; 1775 1776 bdevname(reg->hr_bdev, reg->hr_dev_name); 1777 1778 sectsize = bdev_logical_block_size(reg->hr_bdev); 1779 if (sectsize != reg->hr_block_bytes) { 1780 mlog(ML_ERROR, 1781 "blocksize %u incorrect for device, expected %d", 1782 reg->hr_block_bytes, sectsize); 1783 ret = -EINVAL; 1784 goto out3; 1785 } 1786 1787 o2hb_init_region_params(reg); 1788 1789 /* Generation of zero is invalid */ 1790 do { 1791 get_random_bytes(®->hr_generation, 1792 sizeof(reg->hr_generation)); 1793 } while (reg->hr_generation == 0); 1794 1795 ret = o2hb_map_slot_data(reg); 1796 if (ret) { 1797 mlog_errno(ret); 1798 goto out3; 1799 } 1800 1801 ret = o2hb_populate_slot_data(reg); 1802 if (ret) { 1803 mlog_errno(ret); 1804 goto out3; 1805 } 1806 1807 INIT_DELAYED_WORK(®->hr_write_timeout_work, o2hb_write_timeout); 1808 1809 /* 1810 * A node is considered live after it has beat LIVE_THRESHOLD 1811 * times. We're not steady until we've given them a chance 1812 * _after_ our first read. 1813 * The default threshold is bare minimum so as to limit the delay 1814 * during mounts. For global heartbeat, the threshold doubled for the 1815 * first region. 1816 */ 1817 live_threshold = O2HB_LIVE_THRESHOLD; 1818 if (o2hb_global_heartbeat_active()) { 1819 spin_lock(&o2hb_live_lock); 1820 if (bitmap_weight(o2hb_region_bitmap, O2NM_MAX_REGIONS) == 1) 1821 live_threshold <<= 1; 1822 spin_unlock(&o2hb_live_lock); 1823 } 1824 ++live_threshold; 1825 atomic_set(®->hr_steady_iterations, live_threshold); 1826 /* unsteady_iterations is double the steady_iterations */ 1827 atomic_set(®->hr_unsteady_iterations, (live_threshold << 1)); 1828 1829 hb_task = kthread_run(o2hb_thread, reg, "o2hb-%s", 1830 reg->hr_item.ci_name); 1831 if (IS_ERR(hb_task)) { 1832 ret = PTR_ERR(hb_task); 1833 mlog_errno(ret); 1834 goto out3; 1835 } 1836 1837 spin_lock(&o2hb_live_lock); 1838 reg->hr_task = hb_task; 1839 spin_unlock(&o2hb_live_lock); 1840 1841 ret = wait_event_interruptible(o2hb_steady_queue, 1842 atomic_read(®->hr_steady_iterations) == 0); 1843 if (ret) { 1844 atomic_set(®->hr_steady_iterations, 0); 1845 reg->hr_aborted_start = 1; 1846 } 1847 1848 if (reg->hr_aborted_start) { 1849 ret = -EIO; 1850 goto out3; 1851 } 1852 1853 /* Ok, we were woken. Make sure it wasn't by drop_item() */ 1854 spin_lock(&o2hb_live_lock); 1855 hb_task = reg->hr_task; 1856 if (o2hb_global_heartbeat_active()) 1857 set_bit(reg->hr_region_num, o2hb_live_region_bitmap); 1858 spin_unlock(&o2hb_live_lock); 1859 1860 if (hb_task) 1861 ret = count; 1862 else 1863 ret = -EIO; 1864 1865 if (hb_task && o2hb_global_heartbeat_active()) 1866 printk(KERN_NOTICE "o2hb: Heartbeat started on region %s (%s)\n", 1867 config_item_name(®->hr_item), reg->hr_dev_name); 1868 1869 out3: 1870 iput(inode); 1871 out2: 1872 fdput(f); 1873 out: 1874 if (ret < 0) { 1875 if (reg->hr_bdev) { 1876 blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE); 1877 reg->hr_bdev = NULL; 1878 } 1879 } 1880 return ret; 1881 } 1882 1883 static ssize_t o2hb_region_pid_read(struct o2hb_region *reg, 1884 char *page) 1885 { 1886 pid_t pid = 0; 1887 1888 spin_lock(&o2hb_live_lock); 1889 if (reg->hr_task) 1890 pid = task_pid_nr(reg->hr_task); 1891 spin_unlock(&o2hb_live_lock); 1892 1893 if (!pid) 1894 return 0; 1895 1896 return sprintf(page, "%u\n", pid); 1897 } 1898 1899 struct o2hb_region_attribute { 1900 struct configfs_attribute attr; 1901 ssize_t (*show)(struct o2hb_region *, char *); 1902 ssize_t (*store)(struct o2hb_region *, const char *, size_t); 1903 }; 1904 1905 static struct o2hb_region_attribute o2hb_region_attr_block_bytes = { 1906 .attr = { .ca_owner = THIS_MODULE, 1907 .ca_name = "block_bytes", 1908 .ca_mode = S_IRUGO | S_IWUSR }, 1909 .show = o2hb_region_block_bytes_read, 1910 .store = o2hb_region_block_bytes_write, 1911 }; 1912 1913 static struct o2hb_region_attribute o2hb_region_attr_start_block = { 1914 .attr = { .ca_owner = THIS_MODULE, 1915 .ca_name = "start_block", 1916 .ca_mode = S_IRUGO | S_IWUSR }, 1917 .show = o2hb_region_start_block_read, 1918 .store = o2hb_region_start_block_write, 1919 }; 1920 1921 static struct o2hb_region_attribute o2hb_region_attr_blocks = { 1922 .attr = { .ca_owner = THIS_MODULE, 1923 .ca_name = "blocks", 1924 .ca_mode = S_IRUGO | S_IWUSR }, 1925 .show = o2hb_region_blocks_read, 1926 .store = o2hb_region_blocks_write, 1927 }; 1928 1929 static struct o2hb_region_attribute o2hb_region_attr_dev = { 1930 .attr = { .ca_owner = THIS_MODULE, 1931 .ca_name = "dev", 1932 .ca_mode = S_IRUGO | S_IWUSR }, 1933 .show = o2hb_region_dev_read, 1934 .store = o2hb_region_dev_write, 1935 }; 1936 1937 static struct o2hb_region_attribute o2hb_region_attr_pid = { 1938 .attr = { .ca_owner = THIS_MODULE, 1939 .ca_name = "pid", 1940 .ca_mode = S_IRUGO | S_IRUSR }, 1941 .show = o2hb_region_pid_read, 1942 }; 1943 1944 static struct configfs_attribute *o2hb_region_attrs[] = { 1945 &o2hb_region_attr_block_bytes.attr, 1946 &o2hb_region_attr_start_block.attr, 1947 &o2hb_region_attr_blocks.attr, 1948 &o2hb_region_attr_dev.attr, 1949 &o2hb_region_attr_pid.attr, 1950 NULL, 1951 }; 1952 1953 static ssize_t o2hb_region_show(struct config_item *item, 1954 struct configfs_attribute *attr, 1955 char *page) 1956 { 1957 struct o2hb_region *reg = to_o2hb_region(item); 1958 struct o2hb_region_attribute *o2hb_region_attr = 1959 container_of(attr, struct o2hb_region_attribute, attr); 1960 ssize_t ret = 0; 1961 1962 if (o2hb_region_attr->show) 1963 ret = o2hb_region_attr->show(reg, page); 1964 return ret; 1965 } 1966 1967 static ssize_t o2hb_region_store(struct config_item *item, 1968 struct configfs_attribute *attr, 1969 const char *page, size_t count) 1970 { 1971 struct o2hb_region *reg = to_o2hb_region(item); 1972 struct o2hb_region_attribute *o2hb_region_attr = 1973 container_of(attr, struct o2hb_region_attribute, attr); 1974 ssize_t ret = -EINVAL; 1975 1976 if (o2hb_region_attr->store) 1977 ret = o2hb_region_attr->store(reg, page, count); 1978 return ret; 1979 } 1980 1981 static struct configfs_item_operations o2hb_region_item_ops = { 1982 .release = o2hb_region_release, 1983 .show_attribute = o2hb_region_show, 1984 .store_attribute = o2hb_region_store, 1985 }; 1986 1987 static struct config_item_type o2hb_region_type = { 1988 .ct_item_ops = &o2hb_region_item_ops, 1989 .ct_attrs = o2hb_region_attrs, 1990 .ct_owner = THIS_MODULE, 1991 }; 1992 1993 /* heartbeat set */ 1994 1995 struct o2hb_heartbeat_group { 1996 struct config_group hs_group; 1997 /* some stuff? */ 1998 }; 1999 2000 static struct o2hb_heartbeat_group *to_o2hb_heartbeat_group(struct config_group *group) 2001 { 2002 return group ? 2003 container_of(group, struct o2hb_heartbeat_group, hs_group) 2004 : NULL; 2005 } 2006 2007 static int o2hb_debug_region_init(struct o2hb_region *reg, struct dentry *dir) 2008 { 2009 int ret = -ENOMEM; 2010 2011 reg->hr_debug_dir = 2012 debugfs_create_dir(config_item_name(®->hr_item), dir); 2013 if (IS_ERR_OR_NULL(reg->hr_debug_dir)) { 2014 ret = reg->hr_debug_dir ? PTR_ERR(reg->hr_debug_dir) : -ENOMEM; 2015 mlog_errno(ret); 2016 goto bail; 2017 } 2018 2019 reg->hr_debug_livenodes = 2020 o2hb_debug_create(O2HB_DEBUG_LIVENODES, 2021 reg->hr_debug_dir, 2022 &(reg->hr_db_livenodes), 2023 sizeof(*(reg->hr_db_livenodes)), 2024 O2HB_DB_TYPE_REGION_LIVENODES, 2025 sizeof(reg->hr_live_node_bitmap), 2026 O2NM_MAX_NODES, reg); 2027 if (IS_ERR_OR_NULL(reg->hr_debug_livenodes)) { 2028 ret = reg->hr_debug_livenodes ? 2029 PTR_ERR(reg->hr_debug_livenodes) : -ENOMEM; 2030 mlog_errno(ret); 2031 goto bail; 2032 } 2033 2034 reg->hr_debug_regnum = 2035 o2hb_debug_create(O2HB_DEBUG_REGION_NUMBER, 2036 reg->hr_debug_dir, 2037 &(reg->hr_db_regnum), 2038 sizeof(*(reg->hr_db_regnum)), 2039 O2HB_DB_TYPE_REGION_NUMBER, 2040 0, O2NM_MAX_NODES, reg); 2041 if (IS_ERR_OR_NULL(reg->hr_debug_regnum)) { 2042 ret = reg->hr_debug_regnum ? 2043 PTR_ERR(reg->hr_debug_regnum) : -ENOMEM; 2044 mlog_errno(ret); 2045 goto bail; 2046 } 2047 2048 reg->hr_debug_elapsed_time = 2049 o2hb_debug_create(O2HB_DEBUG_REGION_ELAPSED_TIME, 2050 reg->hr_debug_dir, 2051 &(reg->hr_db_elapsed_time), 2052 sizeof(*(reg->hr_db_elapsed_time)), 2053 O2HB_DB_TYPE_REGION_ELAPSED_TIME, 2054 0, 0, reg); 2055 if (IS_ERR_OR_NULL(reg->hr_debug_elapsed_time)) { 2056 ret = reg->hr_debug_elapsed_time ? 2057 PTR_ERR(reg->hr_debug_elapsed_time) : -ENOMEM; 2058 mlog_errno(ret); 2059 goto bail; 2060 } 2061 2062 reg->hr_debug_pinned = 2063 o2hb_debug_create(O2HB_DEBUG_REGION_PINNED, 2064 reg->hr_debug_dir, 2065 &(reg->hr_db_pinned), 2066 sizeof(*(reg->hr_db_pinned)), 2067 O2HB_DB_TYPE_REGION_PINNED, 2068 0, 0, reg); 2069 if (IS_ERR_OR_NULL(reg->hr_debug_pinned)) { 2070 ret = reg->hr_debug_pinned ? 2071 PTR_ERR(reg->hr_debug_pinned) : -ENOMEM; 2072 mlog_errno(ret); 2073 goto bail; 2074 } 2075 2076 return 0; 2077 bail: 2078 debugfs_remove_recursive(reg->hr_debug_dir); 2079 return ret; 2080 } 2081 2082 static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *group, 2083 const char *name) 2084 { 2085 struct o2hb_region *reg = NULL; 2086 int ret; 2087 2088 reg = kzalloc(sizeof(struct o2hb_region), GFP_KERNEL); 2089 if (reg == NULL) 2090 return ERR_PTR(-ENOMEM); 2091 2092 if (strlen(name) > O2HB_MAX_REGION_NAME_LEN) { 2093 ret = -ENAMETOOLONG; 2094 goto free; 2095 } 2096 2097 spin_lock(&o2hb_live_lock); 2098 reg->hr_region_num = 0; 2099 if (o2hb_global_heartbeat_active()) { 2100 reg->hr_region_num = find_first_zero_bit(o2hb_region_bitmap, 2101 O2NM_MAX_REGIONS); 2102 if (reg->hr_region_num >= O2NM_MAX_REGIONS) { 2103 spin_unlock(&o2hb_live_lock); 2104 ret = -EFBIG; 2105 goto free; 2106 } 2107 set_bit(reg->hr_region_num, o2hb_region_bitmap); 2108 } 2109 list_add_tail(®->hr_all_item, &o2hb_all_regions); 2110 spin_unlock(&o2hb_live_lock); 2111 2112 config_item_init_type_name(®->hr_item, name, &o2hb_region_type); 2113 2114 ret = o2hb_debug_region_init(reg, o2hb_debug_dir); 2115 if (ret) { 2116 config_item_put(®->hr_item); 2117 goto free; 2118 } 2119 2120 return ®->hr_item; 2121 free: 2122 kfree(reg); 2123 return ERR_PTR(ret); 2124 } 2125 2126 static void o2hb_heartbeat_group_drop_item(struct config_group *group, 2127 struct config_item *item) 2128 { 2129 struct task_struct *hb_task; 2130 struct o2hb_region *reg = to_o2hb_region(item); 2131 int quorum_region = 0; 2132 2133 /* stop the thread when the user removes the region dir */ 2134 spin_lock(&o2hb_live_lock); 2135 hb_task = reg->hr_task; 2136 reg->hr_task = NULL; 2137 reg->hr_item_dropped = 1; 2138 spin_unlock(&o2hb_live_lock); 2139 2140 if (hb_task) 2141 kthread_stop(hb_task); 2142 2143 if (o2hb_global_heartbeat_active()) { 2144 spin_lock(&o2hb_live_lock); 2145 clear_bit(reg->hr_region_num, o2hb_region_bitmap); 2146 clear_bit(reg->hr_region_num, o2hb_live_region_bitmap); 2147 if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap)) 2148 quorum_region = 1; 2149 clear_bit(reg->hr_region_num, o2hb_quorum_region_bitmap); 2150 spin_unlock(&o2hb_live_lock); 2151 printk(KERN_NOTICE "o2hb: Heartbeat %s on region %s (%s)\n", 2152 ((atomic_read(®->hr_steady_iterations) == 0) ? 2153 "stopped" : "start aborted"), config_item_name(item), 2154 reg->hr_dev_name); 2155 } 2156 2157 /* 2158 * If we're racing a dev_write(), we need to wake them. They will 2159 * check reg->hr_task 2160 */ 2161 if (atomic_read(®->hr_steady_iterations) != 0) { 2162 reg->hr_aborted_start = 1; 2163 atomic_set(®->hr_steady_iterations, 0); 2164 wake_up(&o2hb_steady_queue); 2165 } 2166 2167 config_item_put(item); 2168 2169 if (!o2hb_global_heartbeat_active() || !quorum_region) 2170 return; 2171 2172 /* 2173 * If global heartbeat active and there are dependent users, 2174 * pin all regions if quorum region count <= CUT_OFF 2175 */ 2176 spin_lock(&o2hb_live_lock); 2177 2178 if (!o2hb_dependent_users) 2179 goto unlock; 2180 2181 if (bitmap_weight(o2hb_quorum_region_bitmap, 2182 O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF) 2183 o2hb_region_pin(NULL); 2184 2185 unlock: 2186 spin_unlock(&o2hb_live_lock); 2187 } 2188 2189 struct o2hb_heartbeat_group_attribute { 2190 struct configfs_attribute attr; 2191 ssize_t (*show)(struct o2hb_heartbeat_group *, char *); 2192 ssize_t (*store)(struct o2hb_heartbeat_group *, const char *, size_t); 2193 }; 2194 2195 static ssize_t o2hb_heartbeat_group_show(struct config_item *item, 2196 struct configfs_attribute *attr, 2197 char *page) 2198 { 2199 struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item)); 2200 struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr = 2201 container_of(attr, struct o2hb_heartbeat_group_attribute, attr); 2202 ssize_t ret = 0; 2203 2204 if (o2hb_heartbeat_group_attr->show) 2205 ret = o2hb_heartbeat_group_attr->show(reg, page); 2206 return ret; 2207 } 2208 2209 static ssize_t o2hb_heartbeat_group_store(struct config_item *item, 2210 struct configfs_attribute *attr, 2211 const char *page, size_t count) 2212 { 2213 struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item)); 2214 struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr = 2215 container_of(attr, struct o2hb_heartbeat_group_attribute, attr); 2216 ssize_t ret = -EINVAL; 2217 2218 if (o2hb_heartbeat_group_attr->store) 2219 ret = o2hb_heartbeat_group_attr->store(reg, page, count); 2220 return ret; 2221 } 2222 2223 static ssize_t o2hb_heartbeat_group_threshold_show(struct o2hb_heartbeat_group *group, 2224 char *page) 2225 { 2226 return sprintf(page, "%u\n", o2hb_dead_threshold); 2227 } 2228 2229 static ssize_t o2hb_heartbeat_group_threshold_store(struct o2hb_heartbeat_group *group, 2230 const char *page, 2231 size_t count) 2232 { 2233 unsigned long tmp; 2234 char *p = (char *)page; 2235 2236 tmp = simple_strtoul(p, &p, 10); 2237 if (!p || (*p && (*p != '\n'))) 2238 return -EINVAL; 2239 2240 /* this will validate ranges for us. */ 2241 o2hb_dead_threshold_set((unsigned int) tmp); 2242 2243 return count; 2244 } 2245 2246 static 2247 ssize_t o2hb_heartbeat_group_mode_show(struct o2hb_heartbeat_group *group, 2248 char *page) 2249 { 2250 return sprintf(page, "%s\n", 2251 o2hb_heartbeat_mode_desc[o2hb_heartbeat_mode]); 2252 } 2253 2254 static 2255 ssize_t o2hb_heartbeat_group_mode_store(struct o2hb_heartbeat_group *group, 2256 const char *page, size_t count) 2257 { 2258 unsigned int i; 2259 int ret; 2260 size_t len; 2261 2262 len = (page[count - 1] == '\n') ? count - 1 : count; 2263 if (!len) 2264 return -EINVAL; 2265 2266 for (i = 0; i < O2HB_HEARTBEAT_NUM_MODES; ++i) { 2267 if (strncasecmp(page, o2hb_heartbeat_mode_desc[i], len)) 2268 continue; 2269 2270 ret = o2hb_global_heartbeat_mode_set(i); 2271 if (!ret) 2272 printk(KERN_NOTICE "o2hb: Heartbeat mode set to %s\n", 2273 o2hb_heartbeat_mode_desc[i]); 2274 return count; 2275 } 2276 2277 return -EINVAL; 2278 2279 } 2280 2281 static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_threshold = { 2282 .attr = { .ca_owner = THIS_MODULE, 2283 .ca_name = "dead_threshold", 2284 .ca_mode = S_IRUGO | S_IWUSR }, 2285 .show = o2hb_heartbeat_group_threshold_show, 2286 .store = o2hb_heartbeat_group_threshold_store, 2287 }; 2288 2289 static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_mode = { 2290 .attr = { .ca_owner = THIS_MODULE, 2291 .ca_name = "mode", 2292 .ca_mode = S_IRUGO | S_IWUSR }, 2293 .show = o2hb_heartbeat_group_mode_show, 2294 .store = o2hb_heartbeat_group_mode_store, 2295 }; 2296 2297 static struct configfs_attribute *o2hb_heartbeat_group_attrs[] = { 2298 &o2hb_heartbeat_group_attr_threshold.attr, 2299 &o2hb_heartbeat_group_attr_mode.attr, 2300 NULL, 2301 }; 2302 2303 static struct configfs_item_operations o2hb_heartbeat_group_item_ops = { 2304 .show_attribute = o2hb_heartbeat_group_show, 2305 .store_attribute = o2hb_heartbeat_group_store, 2306 }; 2307 2308 static struct configfs_group_operations o2hb_heartbeat_group_group_ops = { 2309 .make_item = o2hb_heartbeat_group_make_item, 2310 .drop_item = o2hb_heartbeat_group_drop_item, 2311 }; 2312 2313 static struct config_item_type o2hb_heartbeat_group_type = { 2314 .ct_group_ops = &o2hb_heartbeat_group_group_ops, 2315 .ct_item_ops = &o2hb_heartbeat_group_item_ops, 2316 .ct_attrs = o2hb_heartbeat_group_attrs, 2317 .ct_owner = THIS_MODULE, 2318 }; 2319 2320 /* this is just here to avoid touching group in heartbeat.h which the 2321 * entire damn world #includes */ 2322 struct config_group *o2hb_alloc_hb_set(void) 2323 { 2324 struct o2hb_heartbeat_group *hs = NULL; 2325 struct config_group *ret = NULL; 2326 2327 hs = kzalloc(sizeof(struct o2hb_heartbeat_group), GFP_KERNEL); 2328 if (hs == NULL) 2329 goto out; 2330 2331 config_group_init_type_name(&hs->hs_group, "heartbeat", 2332 &o2hb_heartbeat_group_type); 2333 2334 ret = &hs->hs_group; 2335 out: 2336 if (ret == NULL) 2337 kfree(hs); 2338 return ret; 2339 } 2340 2341 void o2hb_free_hb_set(struct config_group *group) 2342 { 2343 struct o2hb_heartbeat_group *hs = to_o2hb_heartbeat_group(group); 2344 kfree(hs); 2345 } 2346 2347 /* hb callback registration and issuing */ 2348 2349 static struct o2hb_callback *hbcall_from_type(enum o2hb_callback_type type) 2350 { 2351 if (type == O2HB_NUM_CB) 2352 return ERR_PTR(-EINVAL); 2353 2354 return &o2hb_callbacks[type]; 2355 } 2356 2357 void o2hb_setup_callback(struct o2hb_callback_func *hc, 2358 enum o2hb_callback_type type, 2359 o2hb_cb_func *func, 2360 void *data, 2361 int priority) 2362 { 2363 INIT_LIST_HEAD(&hc->hc_item); 2364 hc->hc_func = func; 2365 hc->hc_data = data; 2366 hc->hc_priority = priority; 2367 hc->hc_type = type; 2368 hc->hc_magic = O2HB_CB_MAGIC; 2369 } 2370 EXPORT_SYMBOL_GPL(o2hb_setup_callback); 2371 2372 /* 2373 * In local heartbeat mode, region_uuid passed matches the dlm domain name. 2374 * In global heartbeat mode, region_uuid passed is NULL. 2375 * 2376 * In local, we only pin the matching region. In global we pin all the active 2377 * regions. 2378 */ 2379 static int o2hb_region_pin(const char *region_uuid) 2380 { 2381 int ret = 0, found = 0; 2382 struct o2hb_region *reg; 2383 char *uuid; 2384 2385 assert_spin_locked(&o2hb_live_lock); 2386 2387 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) { 2388 if (reg->hr_item_dropped) 2389 continue; 2390 2391 uuid = config_item_name(®->hr_item); 2392 2393 /* local heartbeat */ 2394 if (region_uuid) { 2395 if (strcmp(region_uuid, uuid)) 2396 continue; 2397 found = 1; 2398 } 2399 2400 if (reg->hr_item_pinned || reg->hr_item_dropped) 2401 goto skip_pin; 2402 2403 /* Ignore ENOENT only for local hb (userdlm domain) */ 2404 ret = o2nm_depend_item(®->hr_item); 2405 if (!ret) { 2406 mlog(ML_CLUSTER, "Pin region %s\n", uuid); 2407 reg->hr_item_pinned = 1; 2408 } else { 2409 if (ret == -ENOENT && found) 2410 ret = 0; 2411 else { 2412 mlog(ML_ERROR, "Pin region %s fails with %d\n", 2413 uuid, ret); 2414 break; 2415 } 2416 } 2417 skip_pin: 2418 if (found) 2419 break; 2420 } 2421 2422 return ret; 2423 } 2424 2425 /* 2426 * In local heartbeat mode, region_uuid passed matches the dlm domain name. 2427 * In global heartbeat mode, region_uuid passed is NULL. 2428 * 2429 * In local, we only unpin the matching region. In global we unpin all the 2430 * active regions. 2431 */ 2432 static void o2hb_region_unpin(const char *region_uuid) 2433 { 2434 struct o2hb_region *reg; 2435 char *uuid; 2436 int found = 0; 2437 2438 assert_spin_locked(&o2hb_live_lock); 2439 2440 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) { 2441 if (reg->hr_item_dropped) 2442 continue; 2443 2444 uuid = config_item_name(®->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(®->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 (bitmap_weight(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 *f; 2516 struct o2hb_callback *hbcall; 2517 int ret; 2518 2519 BUG_ON(hc->hc_magic != O2HB_CB_MAGIC); 2520 BUG_ON(!list_empty(&hc->hc_item)); 2521 2522 hbcall = hbcall_from_type(hc->hc_type); 2523 if (IS_ERR(hbcall)) { 2524 ret = PTR_ERR(hbcall); 2525 goto out; 2526 } 2527 2528 if (region_uuid) { 2529 ret = o2hb_region_inc_user(region_uuid); 2530 if (ret) { 2531 mlog_errno(ret); 2532 goto out; 2533 } 2534 } 2535 2536 down_write(&o2hb_callback_sem); 2537 2538 list_for_each_entry(f, &hbcall->list, hc_item) { 2539 if (hc->hc_priority < f->hc_priority) { 2540 list_add_tail(&hc->hc_item, &f->hc_item); 2541 break; 2542 } 2543 } 2544 if (list_empty(&hc->hc_item)) 2545 list_add_tail(&hc->hc_item, &hbcall->list); 2546 2547 up_write(&o2hb_callback_sem); 2548 ret = 0; 2549 out: 2550 mlog(ML_CLUSTER, "returning %d on behalf of %p for funcs %p\n", 2551 ret, __builtin_return_address(0), hc); 2552 return ret; 2553 } 2554 EXPORT_SYMBOL_GPL(o2hb_register_callback); 2555 2556 void o2hb_unregister_callback(const char *region_uuid, 2557 struct o2hb_callback_func *hc) 2558 { 2559 BUG_ON(hc->hc_magic != O2HB_CB_MAGIC); 2560 2561 mlog(ML_CLUSTER, "on behalf of %p for funcs %p\n", 2562 __builtin_return_address(0), hc); 2563 2564 /* XXX Can this happen _with_ a region reference? */ 2565 if (list_empty(&hc->hc_item)) 2566 return; 2567 2568 if (region_uuid) 2569 o2hb_region_dec_user(region_uuid); 2570 2571 down_write(&o2hb_callback_sem); 2572 2573 list_del_init(&hc->hc_item); 2574 2575 up_write(&o2hb_callback_sem); 2576 } 2577 EXPORT_SYMBOL_GPL(o2hb_unregister_callback); 2578 2579 int o2hb_check_node_heartbeating(u8 node_num) 2580 { 2581 unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; 2582 2583 o2hb_fill_node_map(testing_map, sizeof(testing_map)); 2584 if (!test_bit(node_num, testing_map)) { 2585 mlog(ML_HEARTBEAT, 2586 "node (%u) does not have heartbeating enabled.\n", 2587 node_num); 2588 return 0; 2589 } 2590 2591 return 1; 2592 } 2593 EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating); 2594 2595 int o2hb_check_node_heartbeating_no_sem(u8 node_num) 2596 { 2597 unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; 2598 unsigned long flags; 2599 2600 spin_lock_irqsave(&o2hb_live_lock, flags); 2601 o2hb_fill_node_map_from_callback(testing_map, sizeof(testing_map)); 2602 spin_unlock_irqrestore(&o2hb_live_lock, flags); 2603 if (!test_bit(node_num, testing_map)) { 2604 mlog(ML_HEARTBEAT, 2605 "node (%u) does not have heartbeating enabled.\n", 2606 node_num); 2607 return 0; 2608 } 2609 2610 return 1; 2611 } 2612 EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating_no_sem); 2613 2614 int o2hb_check_node_heartbeating_from_callback(u8 node_num) 2615 { 2616 unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)]; 2617 2618 o2hb_fill_node_map_from_callback(testing_map, sizeof(testing_map)); 2619 if (!test_bit(node_num, testing_map)) { 2620 mlog(ML_HEARTBEAT, 2621 "node (%u) does not have heartbeating enabled.\n", 2622 node_num); 2623 return 0; 2624 } 2625 2626 return 1; 2627 } 2628 EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating_from_callback); 2629 2630 /* Makes sure our local node is configured with a node number, and is 2631 * heartbeating. */ 2632 int o2hb_check_local_node_heartbeating(void) 2633 { 2634 u8 node_num; 2635 2636 /* if this node was set then we have networking */ 2637 node_num = o2nm_this_node(); 2638 if (node_num == O2NM_MAX_NODES) { 2639 mlog(ML_HEARTBEAT, "this node has not been configured.\n"); 2640 return 0; 2641 } 2642 2643 return o2hb_check_node_heartbeating(node_num); 2644 } 2645 EXPORT_SYMBOL_GPL(o2hb_check_local_node_heartbeating); 2646 2647 /* 2648 * this is just a hack until we get the plumbing which flips file systems 2649 * read only and drops the hb ref instead of killing the node dead. 2650 */ 2651 void o2hb_stop_all_regions(void) 2652 { 2653 struct o2hb_region *reg; 2654 2655 mlog(ML_ERROR, "stopping heartbeat on all active regions.\n"); 2656 2657 spin_lock(&o2hb_live_lock); 2658 2659 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) 2660 reg->hr_unclean_stop = 1; 2661 2662 spin_unlock(&o2hb_live_lock); 2663 } 2664 EXPORT_SYMBOL_GPL(o2hb_stop_all_regions); 2665 2666 int o2hb_get_all_regions(char *region_uuids, u8 max_regions) 2667 { 2668 struct o2hb_region *reg; 2669 int numregs = 0; 2670 char *p; 2671 2672 spin_lock(&o2hb_live_lock); 2673 2674 p = region_uuids; 2675 list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) { 2676 if (reg->hr_item_dropped) 2677 continue; 2678 2679 mlog(0, "Region: %s\n", config_item_name(®->hr_item)); 2680 if (numregs < max_regions) { 2681 memcpy(p, config_item_name(®->hr_item), 2682 O2HB_MAX_REGION_NAME_LEN); 2683 p += O2HB_MAX_REGION_NAME_LEN; 2684 } 2685 numregs++; 2686 } 2687 2688 spin_unlock(&o2hb_live_lock); 2689 2690 return numregs; 2691 } 2692 EXPORT_SYMBOL_GPL(o2hb_get_all_regions); 2693 2694 int o2hb_global_heartbeat_active(void) 2695 { 2696 return (o2hb_heartbeat_mode == O2HB_HEARTBEAT_GLOBAL); 2697 } 2698 EXPORT_SYMBOL(o2hb_global_heartbeat_active); 2699