1 /* 2 drbd.c 3 4 This file is part of DRBD by Philipp Reisner and Lars Ellenberg. 5 6 Copyright (C) 2001-2008, LINBIT Information Technologies GmbH. 7 Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>. 8 Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>. 9 10 Thanks to Carter Burden, Bart Grantham and Gennadiy Nerubayev 11 from Logicworks, Inc. for making SDP replication support possible. 12 13 drbd is free software; you can redistribute it and/or modify 14 it under the terms of the GNU General Public License as published by 15 the Free Software Foundation; either version 2, or (at your option) 16 any later version. 17 18 drbd is distributed in the hope that it will be useful, 19 but WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 GNU General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with drbd; see the file COPYING. If not, write to 25 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 26 27 */ 28 29 #include <linux/module.h> 30 #include <linux/drbd.h> 31 #include <asm/uaccess.h> 32 #include <asm/types.h> 33 #include <net/sock.h> 34 #include <linux/ctype.h> 35 #include <linux/smp_lock.h> 36 #include <linux/fs.h> 37 #include <linux/file.h> 38 #include <linux/proc_fs.h> 39 #include <linux/init.h> 40 #include <linux/mm.h> 41 #include <linux/memcontrol.h> 42 #include <linux/mm_inline.h> 43 #include <linux/slab.h> 44 #include <linux/random.h> 45 #include <linux/reboot.h> 46 #include <linux/notifier.h> 47 #include <linux/kthread.h> 48 49 #define __KERNEL_SYSCALLS__ 50 #include <linux/unistd.h> 51 #include <linux/vmalloc.h> 52 53 #include <linux/drbd_limits.h> 54 #include "drbd_int.h" 55 #include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */ 56 57 #include "drbd_vli.h" 58 59 struct after_state_chg_work { 60 struct drbd_work w; 61 union drbd_state os; 62 union drbd_state ns; 63 enum chg_state_flags flags; 64 struct completion *done; 65 }; 66 67 int drbdd_init(struct drbd_thread *); 68 int drbd_worker(struct drbd_thread *); 69 int drbd_asender(struct drbd_thread *); 70 71 int drbd_init(void); 72 static int drbd_open(struct block_device *bdev, fmode_t mode); 73 static int drbd_release(struct gendisk *gd, fmode_t mode); 74 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused); 75 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os, 76 union drbd_state ns, enum chg_state_flags flags); 77 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused); 78 static void md_sync_timer_fn(unsigned long data); 79 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused); 80 81 MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, " 82 "Lars Ellenberg <lars@linbit.com>"); 83 MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION); 84 MODULE_VERSION(REL_VERSION); 85 MODULE_LICENSE("GPL"); 86 MODULE_PARM_DESC(minor_count, "Maximum number of drbd devices (1-255)"); 87 MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR); 88 89 #include <linux/moduleparam.h> 90 /* allow_open_on_secondary */ 91 MODULE_PARM_DESC(allow_oos, "DONT USE!"); 92 /* thanks to these macros, if compiled into the kernel (not-module), 93 * this becomes the boot parameter drbd.minor_count */ 94 module_param(minor_count, uint, 0444); 95 module_param(disable_sendpage, bool, 0644); 96 module_param(allow_oos, bool, 0); 97 module_param(cn_idx, uint, 0444); 98 module_param(proc_details, int, 0644); 99 100 #ifdef CONFIG_DRBD_FAULT_INJECTION 101 int enable_faults; 102 int fault_rate; 103 static int fault_count; 104 int fault_devs; 105 /* bitmap of enabled faults */ 106 module_param(enable_faults, int, 0664); 107 /* fault rate % value - applies to all enabled faults */ 108 module_param(fault_rate, int, 0664); 109 /* count of faults inserted */ 110 module_param(fault_count, int, 0664); 111 /* bitmap of devices to insert faults on */ 112 module_param(fault_devs, int, 0644); 113 #endif 114 115 /* module parameter, defined */ 116 unsigned int minor_count = 32; 117 int disable_sendpage; 118 int allow_oos; 119 unsigned int cn_idx = CN_IDX_DRBD; 120 int proc_details; /* Detail level in proc drbd*/ 121 122 /* Module parameter for setting the user mode helper program 123 * to run. Default is /sbin/drbdadm */ 124 char usermode_helper[80] = "/sbin/drbdadm"; 125 126 module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644); 127 128 /* in 2.6.x, our device mapping and config info contains our virtual gendisks 129 * as member "struct gendisk *vdisk;" 130 */ 131 struct drbd_conf **minor_table; 132 133 struct kmem_cache *drbd_request_cache; 134 struct kmem_cache *drbd_ee_cache; /* epoch entries */ 135 struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 136 struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 137 mempool_t *drbd_request_mempool; 138 mempool_t *drbd_ee_mempool; 139 140 /* I do not use a standard mempool, because: 141 1) I want to hand out the pre-allocated objects first. 142 2) I want to be able to interrupt sleeping allocation with a signal. 143 Note: This is a single linked list, the next pointer is the private 144 member of struct page. 145 */ 146 struct page *drbd_pp_pool; 147 spinlock_t drbd_pp_lock; 148 int drbd_pp_vacant; 149 wait_queue_head_t drbd_pp_wait; 150 151 DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5); 152 153 static const struct block_device_operations drbd_ops = { 154 .owner = THIS_MODULE, 155 .open = drbd_open, 156 .release = drbd_release, 157 }; 158 159 #define ARRY_SIZE(A) (sizeof(A)/sizeof(A[0])) 160 161 #ifdef __CHECKER__ 162 /* When checking with sparse, and this is an inline function, sparse will 163 give tons of false positives. When this is a real functions sparse works. 164 */ 165 int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins) 166 { 167 int io_allowed; 168 169 atomic_inc(&mdev->local_cnt); 170 io_allowed = (mdev->state.disk >= mins); 171 if (!io_allowed) { 172 if (atomic_dec_and_test(&mdev->local_cnt)) 173 wake_up(&mdev->misc_wait); 174 } 175 return io_allowed; 176 } 177 178 #endif 179 180 /** 181 * DOC: The transfer log 182 * 183 * The transfer log is a single linked list of &struct drbd_tl_epoch objects. 184 * mdev->newest_tle points to the head, mdev->oldest_tle points to the tail 185 * of the list. There is always at least one &struct drbd_tl_epoch object. 186 * 187 * Each &struct drbd_tl_epoch has a circular double linked list of requests 188 * attached. 189 */ 190 static int tl_init(struct drbd_conf *mdev) 191 { 192 struct drbd_tl_epoch *b; 193 194 /* during device minor initialization, we may well use GFP_KERNEL */ 195 b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL); 196 if (!b) 197 return 0; 198 INIT_LIST_HEAD(&b->requests); 199 INIT_LIST_HEAD(&b->w.list); 200 b->next = NULL; 201 b->br_number = 4711; 202 b->n_req = 0; 203 b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */ 204 205 mdev->oldest_tle = b; 206 mdev->newest_tle = b; 207 INIT_LIST_HEAD(&mdev->out_of_sequence_requests); 208 209 mdev->tl_hash = NULL; 210 mdev->tl_hash_s = 0; 211 212 return 1; 213 } 214 215 static void tl_cleanup(struct drbd_conf *mdev) 216 { 217 D_ASSERT(mdev->oldest_tle == mdev->newest_tle); 218 D_ASSERT(list_empty(&mdev->out_of_sequence_requests)); 219 kfree(mdev->oldest_tle); 220 mdev->oldest_tle = NULL; 221 kfree(mdev->unused_spare_tle); 222 mdev->unused_spare_tle = NULL; 223 kfree(mdev->tl_hash); 224 mdev->tl_hash = NULL; 225 mdev->tl_hash_s = 0; 226 } 227 228 /** 229 * _tl_add_barrier() - Adds a barrier to the transfer log 230 * @mdev: DRBD device. 231 * @new: Barrier to be added before the current head of the TL. 232 * 233 * The caller must hold the req_lock. 234 */ 235 void _tl_add_barrier(struct drbd_conf *mdev, struct drbd_tl_epoch *new) 236 { 237 struct drbd_tl_epoch *newest_before; 238 239 INIT_LIST_HEAD(&new->requests); 240 INIT_LIST_HEAD(&new->w.list); 241 new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */ 242 new->next = NULL; 243 new->n_req = 0; 244 245 newest_before = mdev->newest_tle; 246 /* never send a barrier number == 0, because that is special-cased 247 * when using TCQ for our write ordering code */ 248 new->br_number = (newest_before->br_number+1) ?: 1; 249 if (mdev->newest_tle != new) { 250 mdev->newest_tle->next = new; 251 mdev->newest_tle = new; 252 } 253 } 254 255 /** 256 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL 257 * @mdev: DRBD device. 258 * @barrier_nr: Expected identifier of the DRBD write barrier packet. 259 * @set_size: Expected number of requests before that barrier. 260 * 261 * In case the passed barrier_nr or set_size does not match the oldest 262 * &struct drbd_tl_epoch objects this function will cause a termination 263 * of the connection. 264 */ 265 void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr, 266 unsigned int set_size) 267 { 268 struct drbd_tl_epoch *b, *nob; /* next old barrier */ 269 struct list_head *le, *tle; 270 struct drbd_request *r; 271 272 spin_lock_irq(&mdev->req_lock); 273 274 b = mdev->oldest_tle; 275 276 /* first some paranoia code */ 277 if (b == NULL) { 278 dev_err(DEV, "BAD! BarrierAck #%u received, but no epoch in tl!?\n", 279 barrier_nr); 280 goto bail; 281 } 282 if (b->br_number != barrier_nr) { 283 dev_err(DEV, "BAD! BarrierAck #%u received, expected #%u!\n", 284 barrier_nr, b->br_number); 285 goto bail; 286 } 287 if (b->n_req != set_size) { 288 dev_err(DEV, "BAD! BarrierAck #%u received with n_req=%u, expected n_req=%u!\n", 289 barrier_nr, set_size, b->n_req); 290 goto bail; 291 } 292 293 /* Clean up list of requests processed during current epoch */ 294 list_for_each_safe(le, tle, &b->requests) { 295 r = list_entry(le, struct drbd_request, tl_requests); 296 _req_mod(r, barrier_acked); 297 } 298 /* There could be requests on the list waiting for completion 299 of the write to the local disk. To avoid corruptions of 300 slab's data structures we have to remove the lists head. 301 302 Also there could have been a barrier ack out of sequence, overtaking 303 the write acks - which would be a bug and violating write ordering. 304 To not deadlock in case we lose connection while such requests are 305 still pending, we need some way to find them for the 306 _req_mode(connection_lost_while_pending). 307 308 These have been list_move'd to the out_of_sequence_requests list in 309 _req_mod(, barrier_acked) above. 310 */ 311 list_del_init(&b->requests); 312 313 nob = b->next; 314 if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) { 315 _tl_add_barrier(mdev, b); 316 if (nob) 317 mdev->oldest_tle = nob; 318 /* if nob == NULL b was the only barrier, and becomes the new 319 barrier. Therefore mdev->oldest_tle points already to b */ 320 } else { 321 D_ASSERT(nob != NULL); 322 mdev->oldest_tle = nob; 323 kfree(b); 324 } 325 326 spin_unlock_irq(&mdev->req_lock); 327 dec_ap_pending(mdev); 328 329 return; 330 331 bail: 332 spin_unlock_irq(&mdev->req_lock); 333 drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR)); 334 } 335 336 337 /** 338 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL 339 * @mdev: DRBD device. 340 * 341 * This is called after the connection to the peer was lost. The storage covered 342 * by the requests on the transfer gets marked as our of sync. Called from the 343 * receiver thread and the worker thread. 344 */ 345 void tl_clear(struct drbd_conf *mdev) 346 { 347 struct drbd_tl_epoch *b, *tmp; 348 struct list_head *le, *tle; 349 struct drbd_request *r; 350 int new_initial_bnr = net_random(); 351 352 spin_lock_irq(&mdev->req_lock); 353 354 b = mdev->oldest_tle; 355 while (b) { 356 list_for_each_safe(le, tle, &b->requests) { 357 r = list_entry(le, struct drbd_request, tl_requests); 358 /* It would be nice to complete outside of spinlock. 359 * But this is easier for now. */ 360 _req_mod(r, connection_lost_while_pending); 361 } 362 tmp = b->next; 363 364 /* there could still be requests on that ring list, 365 * in case local io is still pending */ 366 list_del(&b->requests); 367 368 /* dec_ap_pending corresponding to queue_barrier. 369 * the newest barrier may not have been queued yet, 370 * in which case w.cb is still NULL. */ 371 if (b->w.cb != NULL) 372 dec_ap_pending(mdev); 373 374 if (b == mdev->newest_tle) { 375 /* recycle, but reinit! */ 376 D_ASSERT(tmp == NULL); 377 INIT_LIST_HEAD(&b->requests); 378 INIT_LIST_HEAD(&b->w.list); 379 b->w.cb = NULL; 380 b->br_number = new_initial_bnr; 381 b->n_req = 0; 382 383 mdev->oldest_tle = b; 384 break; 385 } 386 kfree(b); 387 b = tmp; 388 } 389 390 /* we expect this list to be empty. */ 391 D_ASSERT(list_empty(&mdev->out_of_sequence_requests)); 392 393 /* but just in case, clean it up anyways! */ 394 list_for_each_safe(le, tle, &mdev->out_of_sequence_requests) { 395 r = list_entry(le, struct drbd_request, tl_requests); 396 /* It would be nice to complete outside of spinlock. 397 * But this is easier for now. */ 398 _req_mod(r, connection_lost_while_pending); 399 } 400 401 /* ensure bit indicating barrier is required is clear */ 402 clear_bit(CREATE_BARRIER, &mdev->flags); 403 404 spin_unlock_irq(&mdev->req_lock); 405 } 406 407 /** 408 * cl_wide_st_chg() - TRUE if the state change is a cluster wide one 409 * @mdev: DRBD device. 410 * @os: old (current) state. 411 * @ns: new (wanted) state. 412 */ 413 static int cl_wide_st_chg(struct drbd_conf *mdev, 414 union drbd_state os, union drbd_state ns) 415 { 416 return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED && 417 ((os.role != R_PRIMARY && ns.role == R_PRIMARY) || 418 (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) || 419 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) || 420 (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))) || 421 (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) || 422 (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S); 423 } 424 425 int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f, 426 union drbd_state mask, union drbd_state val) 427 { 428 unsigned long flags; 429 union drbd_state os, ns; 430 int rv; 431 432 spin_lock_irqsave(&mdev->req_lock, flags); 433 os = mdev->state; 434 ns.i = (os.i & ~mask.i) | val.i; 435 rv = _drbd_set_state(mdev, ns, f, NULL); 436 ns = mdev->state; 437 spin_unlock_irqrestore(&mdev->req_lock, flags); 438 439 return rv; 440 } 441 442 /** 443 * drbd_force_state() - Impose a change which happens outside our control on our state 444 * @mdev: DRBD device. 445 * @mask: mask of state bits to change. 446 * @val: value of new state bits. 447 */ 448 void drbd_force_state(struct drbd_conf *mdev, 449 union drbd_state mask, union drbd_state val) 450 { 451 drbd_change_state(mdev, CS_HARD, mask, val); 452 } 453 454 static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns); 455 static int is_valid_state_transition(struct drbd_conf *, 456 union drbd_state, union drbd_state); 457 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os, 458 union drbd_state ns, int *warn_sync_abort); 459 int drbd_send_state_req(struct drbd_conf *, 460 union drbd_state, union drbd_state); 461 462 static enum drbd_state_ret_codes _req_st_cond(struct drbd_conf *mdev, 463 union drbd_state mask, union drbd_state val) 464 { 465 union drbd_state os, ns; 466 unsigned long flags; 467 int rv; 468 469 if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &mdev->flags)) 470 return SS_CW_SUCCESS; 471 472 if (test_and_clear_bit(CL_ST_CHG_FAIL, &mdev->flags)) 473 return SS_CW_FAILED_BY_PEER; 474 475 rv = 0; 476 spin_lock_irqsave(&mdev->req_lock, flags); 477 os = mdev->state; 478 ns.i = (os.i & ~mask.i) | val.i; 479 ns = sanitize_state(mdev, os, ns, NULL); 480 481 if (!cl_wide_st_chg(mdev, os, ns)) 482 rv = SS_CW_NO_NEED; 483 if (!rv) { 484 rv = is_valid_state(mdev, ns); 485 if (rv == SS_SUCCESS) { 486 rv = is_valid_state_transition(mdev, ns, os); 487 if (rv == SS_SUCCESS) 488 rv = 0; /* cont waiting, otherwise fail. */ 489 } 490 } 491 spin_unlock_irqrestore(&mdev->req_lock, flags); 492 493 return rv; 494 } 495 496 /** 497 * drbd_req_state() - Perform an eventually cluster wide state change 498 * @mdev: DRBD device. 499 * @mask: mask of state bits to change. 500 * @val: value of new state bits. 501 * @f: flags 502 * 503 * Should not be called directly, use drbd_request_state() or 504 * _drbd_request_state(). 505 */ 506 static int drbd_req_state(struct drbd_conf *mdev, 507 union drbd_state mask, union drbd_state val, 508 enum chg_state_flags f) 509 { 510 struct completion done; 511 unsigned long flags; 512 union drbd_state os, ns; 513 int rv; 514 515 init_completion(&done); 516 517 if (f & CS_SERIALIZE) 518 mutex_lock(&mdev->state_mutex); 519 520 spin_lock_irqsave(&mdev->req_lock, flags); 521 os = mdev->state; 522 ns.i = (os.i & ~mask.i) | val.i; 523 ns = sanitize_state(mdev, os, ns, NULL); 524 525 if (cl_wide_st_chg(mdev, os, ns)) { 526 rv = is_valid_state(mdev, ns); 527 if (rv == SS_SUCCESS) 528 rv = is_valid_state_transition(mdev, ns, os); 529 spin_unlock_irqrestore(&mdev->req_lock, flags); 530 531 if (rv < SS_SUCCESS) { 532 if (f & CS_VERBOSE) 533 print_st_err(mdev, os, ns, rv); 534 goto abort; 535 } 536 537 drbd_state_lock(mdev); 538 if (!drbd_send_state_req(mdev, mask, val)) { 539 drbd_state_unlock(mdev); 540 rv = SS_CW_FAILED_BY_PEER; 541 if (f & CS_VERBOSE) 542 print_st_err(mdev, os, ns, rv); 543 goto abort; 544 } 545 546 wait_event(mdev->state_wait, 547 (rv = _req_st_cond(mdev, mask, val))); 548 549 if (rv < SS_SUCCESS) { 550 drbd_state_unlock(mdev); 551 if (f & CS_VERBOSE) 552 print_st_err(mdev, os, ns, rv); 553 goto abort; 554 } 555 spin_lock_irqsave(&mdev->req_lock, flags); 556 os = mdev->state; 557 ns.i = (os.i & ~mask.i) | val.i; 558 rv = _drbd_set_state(mdev, ns, f, &done); 559 drbd_state_unlock(mdev); 560 } else { 561 rv = _drbd_set_state(mdev, ns, f, &done); 562 } 563 564 spin_unlock_irqrestore(&mdev->req_lock, flags); 565 566 if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) { 567 D_ASSERT(current != mdev->worker.task); 568 wait_for_completion(&done); 569 } 570 571 abort: 572 if (f & CS_SERIALIZE) 573 mutex_unlock(&mdev->state_mutex); 574 575 return rv; 576 } 577 578 /** 579 * _drbd_request_state() - Request a state change (with flags) 580 * @mdev: DRBD device. 581 * @mask: mask of state bits to change. 582 * @val: value of new state bits. 583 * @f: flags 584 * 585 * Cousin of drbd_request_state(), useful with the CS_WAIT_COMPLETE 586 * flag, or when logging of failed state change requests is not desired. 587 */ 588 int _drbd_request_state(struct drbd_conf *mdev, union drbd_state mask, 589 union drbd_state val, enum chg_state_flags f) 590 { 591 int rv; 592 593 wait_event(mdev->state_wait, 594 (rv = drbd_req_state(mdev, mask, val, f)) != SS_IN_TRANSIENT_STATE); 595 596 return rv; 597 } 598 599 static void print_st(struct drbd_conf *mdev, char *name, union drbd_state ns) 600 { 601 dev_err(DEV, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c }\n", 602 name, 603 drbd_conn_str(ns.conn), 604 drbd_role_str(ns.role), 605 drbd_role_str(ns.peer), 606 drbd_disk_str(ns.disk), 607 drbd_disk_str(ns.pdsk), 608 ns.susp ? 's' : 'r', 609 ns.aftr_isp ? 'a' : '-', 610 ns.peer_isp ? 'p' : '-', 611 ns.user_isp ? 'u' : '-' 612 ); 613 } 614 615 void print_st_err(struct drbd_conf *mdev, 616 union drbd_state os, union drbd_state ns, int err) 617 { 618 if (err == SS_IN_TRANSIENT_STATE) 619 return; 620 dev_err(DEV, "State change failed: %s\n", drbd_set_st_err_str(err)); 621 print_st(mdev, " state", os); 622 print_st(mdev, "wanted", ns); 623 } 624 625 626 #define drbd_peer_str drbd_role_str 627 #define drbd_pdsk_str drbd_disk_str 628 629 #define drbd_susp_str(A) ((A) ? "1" : "0") 630 #define drbd_aftr_isp_str(A) ((A) ? "1" : "0") 631 #define drbd_peer_isp_str(A) ((A) ? "1" : "0") 632 #define drbd_user_isp_str(A) ((A) ? "1" : "0") 633 634 #define PSC(A) \ 635 ({ if (ns.A != os.A) { \ 636 pbp += sprintf(pbp, #A "( %s -> %s ) ", \ 637 drbd_##A##_str(os.A), \ 638 drbd_##A##_str(ns.A)); \ 639 } }) 640 641 /** 642 * is_valid_state() - Returns an SS_ error code if ns is not valid 643 * @mdev: DRBD device. 644 * @ns: State to consider. 645 */ 646 static int is_valid_state(struct drbd_conf *mdev, union drbd_state ns) 647 { 648 /* See drbd_state_sw_errors in drbd_strings.c */ 649 650 enum drbd_fencing_p fp; 651 int rv = SS_SUCCESS; 652 653 fp = FP_DONT_CARE; 654 if (get_ldev(mdev)) { 655 fp = mdev->ldev->dc.fencing; 656 put_ldev(mdev); 657 } 658 659 if (get_net_conf(mdev)) { 660 if (!mdev->net_conf->two_primaries && 661 ns.role == R_PRIMARY && ns.peer == R_PRIMARY) 662 rv = SS_TWO_PRIMARIES; 663 put_net_conf(mdev); 664 } 665 666 if (rv <= 0) 667 /* already found a reason to abort */; 668 else if (ns.role == R_SECONDARY && mdev->open_cnt) 669 rv = SS_DEVICE_IN_USE; 670 671 else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE) 672 rv = SS_NO_UP_TO_DATE_DISK; 673 674 else if (fp >= FP_RESOURCE && 675 ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN) 676 rv = SS_PRIMARY_NOP; 677 678 else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT) 679 rv = SS_NO_UP_TO_DATE_DISK; 680 681 else if (ns.conn > C_CONNECTED && ns.disk < D_INCONSISTENT) 682 rv = SS_NO_LOCAL_DISK; 683 684 else if (ns.conn > C_CONNECTED && ns.pdsk < D_INCONSISTENT) 685 rv = SS_NO_REMOTE_DISK; 686 687 else if ((ns.conn == C_CONNECTED || 688 ns.conn == C_WF_BITMAP_S || 689 ns.conn == C_SYNC_SOURCE || 690 ns.conn == C_PAUSED_SYNC_S) && 691 ns.disk == D_OUTDATED) 692 rv = SS_CONNECTED_OUTDATES; 693 694 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && 695 (mdev->sync_conf.verify_alg[0] == 0)) 696 rv = SS_NO_VERIFY_ALG; 697 698 else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && 699 mdev->agreed_pro_version < 88) 700 rv = SS_NOT_SUPPORTED; 701 702 return rv; 703 } 704 705 /** 706 * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible 707 * @mdev: DRBD device. 708 * @ns: new state. 709 * @os: old state. 710 */ 711 static int is_valid_state_transition(struct drbd_conf *mdev, 712 union drbd_state ns, union drbd_state os) 713 { 714 int rv = SS_SUCCESS; 715 716 if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) && 717 os.conn > C_CONNECTED) 718 rv = SS_RESYNC_RUNNING; 719 720 if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE) 721 rv = SS_ALREADY_STANDALONE; 722 723 if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS) 724 rv = SS_IS_DISKLESS; 725 726 if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED) 727 rv = SS_NO_NET_CONFIG; 728 729 if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING) 730 rv = SS_LOWER_THAN_OUTDATED; 731 732 if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED) 733 rv = SS_IN_TRANSIENT_STATE; 734 735 if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS) 736 rv = SS_IN_TRANSIENT_STATE; 737 738 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED) 739 rv = SS_NEED_CONNECTION; 740 741 if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && 742 ns.conn != os.conn && os.conn > C_CONNECTED) 743 rv = SS_RESYNC_RUNNING; 744 745 if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) && 746 os.conn < C_CONNECTED) 747 rv = SS_NEED_CONNECTION; 748 749 return rv; 750 } 751 752 /** 753 * sanitize_state() - Resolves implicitly necessary additional changes to a state transition 754 * @mdev: DRBD device. 755 * @os: old state. 756 * @ns: new state. 757 * @warn_sync_abort: 758 * 759 * When we loose connection, we have to set the state of the peers disk (pdsk) 760 * to D_UNKNOWN. This rule and many more along those lines are in this function. 761 */ 762 static union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os, 763 union drbd_state ns, int *warn_sync_abort) 764 { 765 enum drbd_fencing_p fp; 766 767 fp = FP_DONT_CARE; 768 if (get_ldev(mdev)) { 769 fp = mdev->ldev->dc.fencing; 770 put_ldev(mdev); 771 } 772 773 /* Disallow Network errors to configure a device's network part */ 774 if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) && 775 os.conn <= C_DISCONNECTING) 776 ns.conn = os.conn; 777 778 /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow */ 779 if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN && 780 ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING) 781 ns.conn = os.conn; 782 783 /* After C_DISCONNECTING only C_STANDALONE may follow */ 784 if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE) 785 ns.conn = os.conn; 786 787 if (ns.conn < C_CONNECTED) { 788 ns.peer_isp = 0; 789 ns.peer = R_UNKNOWN; 790 if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT) 791 ns.pdsk = D_UNKNOWN; 792 } 793 794 /* Clear the aftr_isp when becoming unconfigured */ 795 if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY) 796 ns.aftr_isp = 0; 797 798 if (ns.conn <= C_DISCONNECTING && ns.disk == D_DISKLESS) 799 ns.pdsk = D_UNKNOWN; 800 801 /* Abort resync if a disk fails/detaches */ 802 if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED && 803 (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) { 804 if (warn_sync_abort) 805 *warn_sync_abort = 1; 806 ns.conn = C_CONNECTED; 807 } 808 809 if (ns.conn >= C_CONNECTED && 810 ((ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED) || 811 (ns.disk == D_NEGOTIATING && ns.conn == C_WF_BITMAP_T))) { 812 switch (ns.conn) { 813 case C_WF_BITMAP_T: 814 case C_PAUSED_SYNC_T: 815 ns.disk = D_OUTDATED; 816 break; 817 case C_CONNECTED: 818 case C_WF_BITMAP_S: 819 case C_SYNC_SOURCE: 820 case C_PAUSED_SYNC_S: 821 ns.disk = D_UP_TO_DATE; 822 break; 823 case C_SYNC_TARGET: 824 ns.disk = D_INCONSISTENT; 825 dev_warn(DEV, "Implicitly set disk state Inconsistent!\n"); 826 break; 827 } 828 if (os.disk == D_OUTDATED && ns.disk == D_UP_TO_DATE) 829 dev_warn(DEV, "Implicitly set disk from Outdated to UpToDate\n"); 830 } 831 832 if (ns.conn >= C_CONNECTED && 833 (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)) { 834 switch (ns.conn) { 835 case C_CONNECTED: 836 case C_WF_BITMAP_T: 837 case C_PAUSED_SYNC_T: 838 case C_SYNC_TARGET: 839 ns.pdsk = D_UP_TO_DATE; 840 break; 841 case C_WF_BITMAP_S: 842 case C_PAUSED_SYNC_S: 843 ns.pdsk = D_OUTDATED; 844 break; 845 case C_SYNC_SOURCE: 846 ns.pdsk = D_INCONSISTENT; 847 dev_warn(DEV, "Implicitly set pdsk Inconsistent!\n"); 848 break; 849 } 850 if (os.pdsk == D_OUTDATED && ns.pdsk == D_UP_TO_DATE) 851 dev_warn(DEV, "Implicitly set pdsk from Outdated to UpToDate\n"); 852 } 853 854 /* Connection breaks down before we finished "Negotiating" */ 855 if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING && 856 get_ldev_if_state(mdev, D_NEGOTIATING)) { 857 if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) { 858 ns.disk = mdev->new_state_tmp.disk; 859 ns.pdsk = mdev->new_state_tmp.pdsk; 860 } else { 861 dev_alert(DEV, "Connection lost while negotiating, no data!\n"); 862 ns.disk = D_DISKLESS; 863 ns.pdsk = D_UNKNOWN; 864 } 865 put_ldev(mdev); 866 } 867 868 if (fp == FP_STONITH && 869 (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) && 870 !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED)) 871 ns.susp = 1; 872 873 if (ns.aftr_isp || ns.peer_isp || ns.user_isp) { 874 if (ns.conn == C_SYNC_SOURCE) 875 ns.conn = C_PAUSED_SYNC_S; 876 if (ns.conn == C_SYNC_TARGET) 877 ns.conn = C_PAUSED_SYNC_T; 878 } else { 879 if (ns.conn == C_PAUSED_SYNC_S) 880 ns.conn = C_SYNC_SOURCE; 881 if (ns.conn == C_PAUSED_SYNC_T) 882 ns.conn = C_SYNC_TARGET; 883 } 884 885 return ns; 886 } 887 888 /* helper for __drbd_set_state */ 889 static void set_ov_position(struct drbd_conf *mdev, enum drbd_conns cs) 890 { 891 if (cs == C_VERIFY_T) { 892 /* starting online verify from an arbitrary position 893 * does not fit well into the existing protocol. 894 * on C_VERIFY_T, we initialize ov_left and friends 895 * implicitly in receive_DataRequest once the 896 * first P_OV_REQUEST is received */ 897 mdev->ov_start_sector = ~(sector_t)0; 898 } else { 899 unsigned long bit = BM_SECT_TO_BIT(mdev->ov_start_sector); 900 if (bit >= mdev->rs_total) 901 mdev->ov_start_sector = 902 BM_BIT_TO_SECT(mdev->rs_total - 1); 903 mdev->ov_position = mdev->ov_start_sector; 904 } 905 } 906 907 /** 908 * __drbd_set_state() - Set a new DRBD state 909 * @mdev: DRBD device. 910 * @ns: new state. 911 * @flags: Flags 912 * @done: Optional completion, that will get completed after the after_state_ch() finished 913 * 914 * Caller needs to hold req_lock, and global_state_lock. Do not call directly. 915 */ 916 int __drbd_set_state(struct drbd_conf *mdev, 917 union drbd_state ns, enum chg_state_flags flags, 918 struct completion *done) 919 { 920 union drbd_state os; 921 int rv = SS_SUCCESS; 922 int warn_sync_abort = 0; 923 struct after_state_chg_work *ascw; 924 925 os = mdev->state; 926 927 ns = sanitize_state(mdev, os, ns, &warn_sync_abort); 928 929 if (ns.i == os.i) 930 return SS_NOTHING_TO_DO; 931 932 if (!(flags & CS_HARD)) { 933 /* pre-state-change checks ; only look at ns */ 934 /* See drbd_state_sw_errors in drbd_strings.c */ 935 936 rv = is_valid_state(mdev, ns); 937 if (rv < SS_SUCCESS) { 938 /* If the old state was illegal as well, then let 939 this happen...*/ 940 941 if (is_valid_state(mdev, os) == rv) { 942 dev_err(DEV, "Considering state change from bad state. " 943 "Error would be: '%s'\n", 944 drbd_set_st_err_str(rv)); 945 print_st(mdev, "old", os); 946 print_st(mdev, "new", ns); 947 rv = is_valid_state_transition(mdev, ns, os); 948 } 949 } else 950 rv = is_valid_state_transition(mdev, ns, os); 951 } 952 953 if (rv < SS_SUCCESS) { 954 if (flags & CS_VERBOSE) 955 print_st_err(mdev, os, ns, rv); 956 return rv; 957 } 958 959 if (warn_sync_abort) 960 dev_warn(DEV, "Resync aborted.\n"); 961 962 { 963 char *pbp, pb[300]; 964 pbp = pb; 965 *pbp = 0; 966 PSC(role); 967 PSC(peer); 968 PSC(conn); 969 PSC(disk); 970 PSC(pdsk); 971 PSC(susp); 972 PSC(aftr_isp); 973 PSC(peer_isp); 974 PSC(user_isp); 975 dev_info(DEV, "%s\n", pb); 976 } 977 978 /* solve the race between becoming unconfigured, 979 * worker doing the cleanup, and 980 * admin reconfiguring us: 981 * on (re)configure, first set CONFIG_PENDING, 982 * then wait for a potentially exiting worker, 983 * start the worker, and schedule one no_op. 984 * then proceed with configuration. 985 */ 986 if (ns.disk == D_DISKLESS && 987 ns.conn == C_STANDALONE && 988 ns.role == R_SECONDARY && 989 !test_and_set_bit(CONFIG_PENDING, &mdev->flags)) 990 set_bit(DEVICE_DYING, &mdev->flags); 991 992 mdev->state.i = ns.i; 993 wake_up(&mdev->misc_wait); 994 wake_up(&mdev->state_wait); 995 996 /* post-state-change actions */ 997 if (os.conn >= C_SYNC_SOURCE && ns.conn <= C_CONNECTED) { 998 set_bit(STOP_SYNC_TIMER, &mdev->flags); 999 mod_timer(&mdev->resync_timer, jiffies); 1000 } 1001 1002 /* aborted verify run. log the last position */ 1003 if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) && 1004 ns.conn < C_CONNECTED) { 1005 mdev->ov_start_sector = 1006 BM_BIT_TO_SECT(mdev->rs_total - mdev->ov_left); 1007 dev_info(DEV, "Online Verify reached sector %llu\n", 1008 (unsigned long long)mdev->ov_start_sector); 1009 } 1010 1011 if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) && 1012 (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) { 1013 dev_info(DEV, "Syncer continues.\n"); 1014 mdev->rs_paused += (long)jiffies-(long)mdev->rs_mark_time; 1015 if (ns.conn == C_SYNC_TARGET) { 1016 if (!test_and_clear_bit(STOP_SYNC_TIMER, &mdev->flags)) 1017 mod_timer(&mdev->resync_timer, jiffies); 1018 /* This if (!test_bit) is only needed for the case 1019 that a device that has ceased to used its timer, 1020 i.e. it is already in drbd_resync_finished() gets 1021 paused and resumed. */ 1022 } 1023 } 1024 1025 if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) && 1026 (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) { 1027 dev_info(DEV, "Resync suspended\n"); 1028 mdev->rs_mark_time = jiffies; 1029 if (ns.conn == C_PAUSED_SYNC_T) 1030 set_bit(STOP_SYNC_TIMER, &mdev->flags); 1031 } 1032 1033 if (os.conn == C_CONNECTED && 1034 (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) { 1035 mdev->ov_position = 0; 1036 mdev->rs_total = 1037 mdev->rs_mark_left = drbd_bm_bits(mdev); 1038 if (mdev->agreed_pro_version >= 90) 1039 set_ov_position(mdev, ns.conn); 1040 else 1041 mdev->ov_start_sector = 0; 1042 mdev->ov_left = mdev->rs_total 1043 - BM_SECT_TO_BIT(mdev->ov_position); 1044 mdev->rs_start = 1045 mdev->rs_mark_time = jiffies; 1046 mdev->ov_last_oos_size = 0; 1047 mdev->ov_last_oos_start = 0; 1048 1049 if (ns.conn == C_VERIFY_S) { 1050 dev_info(DEV, "Starting Online Verify from sector %llu\n", 1051 (unsigned long long)mdev->ov_position); 1052 mod_timer(&mdev->resync_timer, jiffies); 1053 } 1054 } 1055 1056 if (get_ldev(mdev)) { 1057 u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND| 1058 MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE| 1059 MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY); 1060 1061 if (test_bit(CRASHED_PRIMARY, &mdev->flags)) 1062 mdf |= MDF_CRASHED_PRIMARY; 1063 if (mdev->state.role == R_PRIMARY || 1064 (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY)) 1065 mdf |= MDF_PRIMARY_IND; 1066 if (mdev->state.conn > C_WF_REPORT_PARAMS) 1067 mdf |= MDF_CONNECTED_IND; 1068 if (mdev->state.disk > D_INCONSISTENT) 1069 mdf |= MDF_CONSISTENT; 1070 if (mdev->state.disk > D_OUTDATED) 1071 mdf |= MDF_WAS_UP_TO_DATE; 1072 if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT) 1073 mdf |= MDF_PEER_OUT_DATED; 1074 if (mdf != mdev->ldev->md.flags) { 1075 mdev->ldev->md.flags = mdf; 1076 drbd_md_mark_dirty(mdev); 1077 } 1078 if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT) 1079 drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]); 1080 put_ldev(mdev); 1081 } 1082 1083 /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */ 1084 if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT && 1085 os.peer == R_SECONDARY && ns.peer == R_PRIMARY) 1086 set_bit(CONSIDER_RESYNC, &mdev->flags); 1087 1088 /* Receiver should clean up itself */ 1089 if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING) 1090 drbd_thread_stop_nowait(&mdev->receiver); 1091 1092 /* Now the receiver finished cleaning up itself, it should die */ 1093 if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE) 1094 drbd_thread_stop_nowait(&mdev->receiver); 1095 1096 /* Upon network failure, we need to restart the receiver. */ 1097 if (os.conn > C_TEAR_DOWN && 1098 ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT) 1099 drbd_thread_restart_nowait(&mdev->receiver); 1100 1101 ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC); 1102 if (ascw) { 1103 ascw->os = os; 1104 ascw->ns = ns; 1105 ascw->flags = flags; 1106 ascw->w.cb = w_after_state_ch; 1107 ascw->done = done; 1108 drbd_queue_work(&mdev->data.work, &ascw->w); 1109 } else { 1110 dev_warn(DEV, "Could not kmalloc an ascw\n"); 1111 } 1112 1113 return rv; 1114 } 1115 1116 static int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused) 1117 { 1118 struct after_state_chg_work *ascw = 1119 container_of(w, struct after_state_chg_work, w); 1120 after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags); 1121 if (ascw->flags & CS_WAIT_COMPLETE) { 1122 D_ASSERT(ascw->done != NULL); 1123 complete(ascw->done); 1124 } 1125 kfree(ascw); 1126 1127 return 1; 1128 } 1129 1130 static void abw_start_sync(struct drbd_conf *mdev, int rv) 1131 { 1132 if (rv) { 1133 dev_err(DEV, "Writing the bitmap failed not starting resync.\n"); 1134 _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE); 1135 return; 1136 } 1137 1138 switch (mdev->state.conn) { 1139 case C_STARTING_SYNC_T: 1140 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE); 1141 break; 1142 case C_STARTING_SYNC_S: 1143 drbd_start_resync(mdev, C_SYNC_SOURCE); 1144 break; 1145 } 1146 } 1147 1148 /** 1149 * after_state_ch() - Perform after state change actions that may sleep 1150 * @mdev: DRBD device. 1151 * @os: old state. 1152 * @ns: new state. 1153 * @flags: Flags 1154 */ 1155 static void after_state_ch(struct drbd_conf *mdev, union drbd_state os, 1156 union drbd_state ns, enum chg_state_flags flags) 1157 { 1158 enum drbd_fencing_p fp; 1159 1160 if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) { 1161 clear_bit(CRASHED_PRIMARY, &mdev->flags); 1162 if (mdev->p_uuid) 1163 mdev->p_uuid[UI_FLAGS] &= ~((u64)2); 1164 } 1165 1166 fp = FP_DONT_CARE; 1167 if (get_ldev(mdev)) { 1168 fp = mdev->ldev->dc.fencing; 1169 put_ldev(mdev); 1170 } 1171 1172 /* Inform userspace about the change... */ 1173 drbd_bcast_state(mdev, ns); 1174 1175 if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) && 1176 (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE)) 1177 drbd_khelper(mdev, "pri-on-incon-degr"); 1178 1179 /* Here we have the actions that are performed after a 1180 state change. This function might sleep */ 1181 1182 if (fp == FP_STONITH && ns.susp) { 1183 /* case1: The outdate peer handler is successful: 1184 * case2: The connection was established again: */ 1185 if ((os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) || 1186 (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)) { 1187 tl_clear(mdev); 1188 spin_lock_irq(&mdev->req_lock); 1189 _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL); 1190 spin_unlock_irq(&mdev->req_lock); 1191 } 1192 } 1193 /* Do not change the order of the if above and the two below... */ 1194 if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */ 1195 drbd_send_uuids(mdev); 1196 drbd_send_state(mdev); 1197 } 1198 if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S) 1199 drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL, "send_bitmap (WFBitMapS)"); 1200 1201 /* Lost contact to peer's copy of the data */ 1202 if ((os.pdsk >= D_INCONSISTENT && 1203 os.pdsk != D_UNKNOWN && 1204 os.pdsk != D_OUTDATED) 1205 && (ns.pdsk < D_INCONSISTENT || 1206 ns.pdsk == D_UNKNOWN || 1207 ns.pdsk == D_OUTDATED)) { 1208 kfree(mdev->p_uuid); 1209 mdev->p_uuid = NULL; 1210 if (get_ldev(mdev)) { 1211 if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) && 1212 mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) { 1213 drbd_uuid_new_current(mdev); 1214 drbd_send_uuids(mdev); 1215 } 1216 put_ldev(mdev); 1217 } 1218 } 1219 1220 if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) { 1221 if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0) 1222 drbd_uuid_new_current(mdev); 1223 1224 /* D_DISKLESS Peer becomes secondary */ 1225 if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY) 1226 drbd_al_to_on_disk_bm(mdev); 1227 put_ldev(mdev); 1228 } 1229 1230 /* Last part of the attaching process ... */ 1231 if (ns.conn >= C_CONNECTED && 1232 os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) { 1233 kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */ 1234 mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */ 1235 drbd_send_sizes(mdev, 0); /* to start sync... */ 1236 drbd_send_uuids(mdev); 1237 drbd_send_state(mdev); 1238 } 1239 1240 /* We want to pause/continue resync, tell peer. */ 1241 if (ns.conn >= C_CONNECTED && 1242 ((os.aftr_isp != ns.aftr_isp) || 1243 (os.user_isp != ns.user_isp))) 1244 drbd_send_state(mdev); 1245 1246 /* In case one of the isp bits got set, suspend other devices. */ 1247 if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) && 1248 (ns.aftr_isp || ns.peer_isp || ns.user_isp)) 1249 suspend_other_sg(mdev); 1250 1251 /* Make sure the peer gets informed about eventual state 1252 changes (ISP bits) while we were in WFReportParams. */ 1253 if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED) 1254 drbd_send_state(mdev); 1255 1256 /* We are in the progress to start a full sync... */ 1257 if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) || 1258 (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S)) 1259 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync"); 1260 1261 /* We are invalidating our self... */ 1262 if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED && 1263 os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT) 1264 drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate"); 1265 1266 if (os.disk > D_FAILED && ns.disk == D_FAILED) { 1267 enum drbd_io_error_p eh; 1268 1269 eh = EP_PASS_ON; 1270 if (get_ldev_if_state(mdev, D_FAILED)) { 1271 eh = mdev->ldev->dc.on_io_error; 1272 put_ldev(mdev); 1273 } 1274 1275 drbd_rs_cancel_all(mdev); 1276 /* since get_ldev() only works as long as disk>=D_INCONSISTENT, 1277 and it is D_DISKLESS here, local_cnt can only go down, it can 1278 not increase... It will reach zero */ 1279 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt)); 1280 mdev->rs_total = 0; 1281 mdev->rs_failed = 0; 1282 atomic_set(&mdev->rs_pending_cnt, 0); 1283 1284 spin_lock_irq(&mdev->req_lock); 1285 _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL); 1286 spin_unlock_irq(&mdev->req_lock); 1287 1288 if (eh == EP_CALL_HELPER) 1289 drbd_khelper(mdev, "local-io-error"); 1290 } 1291 1292 if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) { 1293 1294 if (os.disk == D_FAILED) /* && ns.disk == D_DISKLESS*/ { 1295 if (drbd_send_state(mdev)) 1296 dev_warn(DEV, "Notified peer that my disk is broken.\n"); 1297 else 1298 dev_err(DEV, "Sending state in drbd_io_error() failed\n"); 1299 } 1300 1301 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt)); 1302 lc_destroy(mdev->resync); 1303 mdev->resync = NULL; 1304 lc_destroy(mdev->act_log); 1305 mdev->act_log = NULL; 1306 __no_warn(local, 1307 drbd_free_bc(mdev->ldev); 1308 mdev->ldev = NULL;); 1309 1310 if (mdev->md_io_tmpp) 1311 __free_page(mdev->md_io_tmpp); 1312 } 1313 1314 /* Disks got bigger while they were detached */ 1315 if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING && 1316 test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) { 1317 if (ns.conn == C_CONNECTED) 1318 resync_after_online_grow(mdev); 1319 } 1320 1321 /* A resync finished or aborted, wake paused devices... */ 1322 if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) || 1323 (os.peer_isp && !ns.peer_isp) || 1324 (os.user_isp && !ns.user_isp)) 1325 resume_next_sg(mdev); 1326 1327 /* Upon network connection, we need to start the receiver */ 1328 if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED) 1329 drbd_thread_start(&mdev->receiver); 1330 1331 /* Terminate worker thread if we are unconfigured - it will be 1332 restarted as needed... */ 1333 if (ns.disk == D_DISKLESS && 1334 ns.conn == C_STANDALONE && 1335 ns.role == R_SECONDARY) { 1336 if (os.aftr_isp != ns.aftr_isp) 1337 resume_next_sg(mdev); 1338 /* set in __drbd_set_state, unless CONFIG_PENDING was set */ 1339 if (test_bit(DEVICE_DYING, &mdev->flags)) 1340 drbd_thread_stop_nowait(&mdev->worker); 1341 } 1342 1343 drbd_md_sync(mdev); 1344 } 1345 1346 1347 static int drbd_thread_setup(void *arg) 1348 { 1349 struct drbd_thread *thi = (struct drbd_thread *) arg; 1350 struct drbd_conf *mdev = thi->mdev; 1351 unsigned long flags; 1352 int retval; 1353 1354 restart: 1355 retval = thi->function(thi); 1356 1357 spin_lock_irqsave(&thi->t_lock, flags); 1358 1359 /* if the receiver has been "Exiting", the last thing it did 1360 * was set the conn state to "StandAlone", 1361 * if now a re-connect request comes in, conn state goes C_UNCONNECTED, 1362 * and receiver thread will be "started". 1363 * drbd_thread_start needs to set "Restarting" in that case. 1364 * t_state check and assignment needs to be within the same spinlock, 1365 * so either thread_start sees Exiting, and can remap to Restarting, 1366 * or thread_start see None, and can proceed as normal. 1367 */ 1368 1369 if (thi->t_state == Restarting) { 1370 dev_info(DEV, "Restarting %s\n", current->comm); 1371 thi->t_state = Running; 1372 spin_unlock_irqrestore(&thi->t_lock, flags); 1373 goto restart; 1374 } 1375 1376 thi->task = NULL; 1377 thi->t_state = None; 1378 smp_mb(); 1379 complete(&thi->stop); 1380 spin_unlock_irqrestore(&thi->t_lock, flags); 1381 1382 dev_info(DEV, "Terminating %s\n", current->comm); 1383 1384 /* Release mod reference taken when thread was started */ 1385 module_put(THIS_MODULE); 1386 return retval; 1387 } 1388 1389 static void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi, 1390 int (*func) (struct drbd_thread *)) 1391 { 1392 spin_lock_init(&thi->t_lock); 1393 thi->task = NULL; 1394 thi->t_state = None; 1395 thi->function = func; 1396 thi->mdev = mdev; 1397 } 1398 1399 int drbd_thread_start(struct drbd_thread *thi) 1400 { 1401 struct drbd_conf *mdev = thi->mdev; 1402 struct task_struct *nt; 1403 unsigned long flags; 1404 1405 const char *me = 1406 thi == &mdev->receiver ? "receiver" : 1407 thi == &mdev->asender ? "asender" : 1408 thi == &mdev->worker ? "worker" : "NONSENSE"; 1409 1410 /* is used from state engine doing drbd_thread_stop_nowait, 1411 * while holding the req lock irqsave */ 1412 spin_lock_irqsave(&thi->t_lock, flags); 1413 1414 switch (thi->t_state) { 1415 case None: 1416 dev_info(DEV, "Starting %s thread (from %s [%d])\n", 1417 me, current->comm, current->pid); 1418 1419 /* Get ref on module for thread - this is released when thread exits */ 1420 if (!try_module_get(THIS_MODULE)) { 1421 dev_err(DEV, "Failed to get module reference in drbd_thread_start\n"); 1422 spin_unlock_irqrestore(&thi->t_lock, flags); 1423 return FALSE; 1424 } 1425 1426 init_completion(&thi->stop); 1427 D_ASSERT(thi->task == NULL); 1428 thi->reset_cpu_mask = 1; 1429 thi->t_state = Running; 1430 spin_unlock_irqrestore(&thi->t_lock, flags); 1431 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */ 1432 1433 nt = kthread_create(drbd_thread_setup, (void *) thi, 1434 "drbd%d_%s", mdev_to_minor(mdev), me); 1435 1436 if (IS_ERR(nt)) { 1437 dev_err(DEV, "Couldn't start thread\n"); 1438 1439 module_put(THIS_MODULE); 1440 return FALSE; 1441 } 1442 spin_lock_irqsave(&thi->t_lock, flags); 1443 thi->task = nt; 1444 thi->t_state = Running; 1445 spin_unlock_irqrestore(&thi->t_lock, flags); 1446 wake_up_process(nt); 1447 break; 1448 case Exiting: 1449 thi->t_state = Restarting; 1450 dev_info(DEV, "Restarting %s thread (from %s [%d])\n", 1451 me, current->comm, current->pid); 1452 /* fall through */ 1453 case Running: 1454 case Restarting: 1455 default: 1456 spin_unlock_irqrestore(&thi->t_lock, flags); 1457 break; 1458 } 1459 1460 return TRUE; 1461 } 1462 1463 1464 void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait) 1465 { 1466 unsigned long flags; 1467 1468 enum drbd_thread_state ns = restart ? Restarting : Exiting; 1469 1470 /* may be called from state engine, holding the req lock irqsave */ 1471 spin_lock_irqsave(&thi->t_lock, flags); 1472 1473 if (thi->t_state == None) { 1474 spin_unlock_irqrestore(&thi->t_lock, flags); 1475 if (restart) 1476 drbd_thread_start(thi); 1477 return; 1478 } 1479 1480 if (thi->t_state != ns) { 1481 if (thi->task == NULL) { 1482 spin_unlock_irqrestore(&thi->t_lock, flags); 1483 return; 1484 } 1485 1486 thi->t_state = ns; 1487 smp_mb(); 1488 init_completion(&thi->stop); 1489 if (thi->task != current) 1490 force_sig(DRBD_SIGKILL, thi->task); 1491 1492 } 1493 1494 spin_unlock_irqrestore(&thi->t_lock, flags); 1495 1496 if (wait) 1497 wait_for_completion(&thi->stop); 1498 } 1499 1500 #ifdef CONFIG_SMP 1501 /** 1502 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs 1503 * @mdev: DRBD device. 1504 * 1505 * Forces all threads of a device onto the same CPU. This is beneficial for 1506 * DRBD's performance. May be overwritten by user's configuration. 1507 */ 1508 void drbd_calc_cpu_mask(struct drbd_conf *mdev) 1509 { 1510 int ord, cpu; 1511 1512 /* user override. */ 1513 if (cpumask_weight(mdev->cpu_mask)) 1514 return; 1515 1516 ord = mdev_to_minor(mdev) % cpumask_weight(cpu_online_mask); 1517 for_each_online_cpu(cpu) { 1518 if (ord-- == 0) { 1519 cpumask_set_cpu(cpu, mdev->cpu_mask); 1520 return; 1521 } 1522 } 1523 /* should not be reached */ 1524 cpumask_setall(mdev->cpu_mask); 1525 } 1526 1527 /** 1528 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread 1529 * @mdev: DRBD device. 1530 * 1531 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die 1532 * prematurely. 1533 */ 1534 void drbd_thread_current_set_cpu(struct drbd_conf *mdev) 1535 { 1536 struct task_struct *p = current; 1537 struct drbd_thread *thi = 1538 p == mdev->asender.task ? &mdev->asender : 1539 p == mdev->receiver.task ? &mdev->receiver : 1540 p == mdev->worker.task ? &mdev->worker : 1541 NULL; 1542 ERR_IF(thi == NULL) 1543 return; 1544 if (!thi->reset_cpu_mask) 1545 return; 1546 thi->reset_cpu_mask = 0; 1547 set_cpus_allowed_ptr(p, mdev->cpu_mask); 1548 } 1549 #endif 1550 1551 /* the appropriate socket mutex must be held already */ 1552 int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock, 1553 enum drbd_packets cmd, struct p_header *h, 1554 size_t size, unsigned msg_flags) 1555 { 1556 int sent, ok; 1557 1558 ERR_IF(!h) return FALSE; 1559 ERR_IF(!size) return FALSE; 1560 1561 h->magic = BE_DRBD_MAGIC; 1562 h->command = cpu_to_be16(cmd); 1563 h->length = cpu_to_be16(size-sizeof(struct p_header)); 1564 1565 sent = drbd_send(mdev, sock, h, size, msg_flags); 1566 1567 ok = (sent == size); 1568 if (!ok) 1569 dev_err(DEV, "short sent %s size=%d sent=%d\n", 1570 cmdname(cmd), (int)size, sent); 1571 return ok; 1572 } 1573 1574 /* don't pass the socket. we may only look at it 1575 * when we hold the appropriate socket mutex. 1576 */ 1577 int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket, 1578 enum drbd_packets cmd, struct p_header *h, size_t size) 1579 { 1580 int ok = 0; 1581 struct socket *sock; 1582 1583 if (use_data_socket) { 1584 mutex_lock(&mdev->data.mutex); 1585 sock = mdev->data.socket; 1586 } else { 1587 mutex_lock(&mdev->meta.mutex); 1588 sock = mdev->meta.socket; 1589 } 1590 1591 /* drbd_disconnect() could have called drbd_free_sock() 1592 * while we were waiting in down()... */ 1593 if (likely(sock != NULL)) 1594 ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0); 1595 1596 if (use_data_socket) 1597 mutex_unlock(&mdev->data.mutex); 1598 else 1599 mutex_unlock(&mdev->meta.mutex); 1600 return ok; 1601 } 1602 1603 int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data, 1604 size_t size) 1605 { 1606 struct p_header h; 1607 int ok; 1608 1609 h.magic = BE_DRBD_MAGIC; 1610 h.command = cpu_to_be16(cmd); 1611 h.length = cpu_to_be16(size); 1612 1613 if (!drbd_get_data_sock(mdev)) 1614 return 0; 1615 1616 ok = (sizeof(h) == 1617 drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0)); 1618 ok = ok && (size == 1619 drbd_send(mdev, mdev->data.socket, data, size, 0)); 1620 1621 drbd_put_data_sock(mdev); 1622 1623 return ok; 1624 } 1625 1626 int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc) 1627 { 1628 struct p_rs_param_89 *p; 1629 struct socket *sock; 1630 int size, rv; 1631 const int apv = mdev->agreed_pro_version; 1632 1633 size = apv <= 87 ? sizeof(struct p_rs_param) 1634 : apv == 88 ? sizeof(struct p_rs_param) 1635 + strlen(mdev->sync_conf.verify_alg) + 1 1636 : /* 89 */ sizeof(struct p_rs_param_89); 1637 1638 /* used from admin command context and receiver/worker context. 1639 * to avoid kmalloc, grab the socket right here, 1640 * then use the pre-allocated sbuf there */ 1641 mutex_lock(&mdev->data.mutex); 1642 sock = mdev->data.socket; 1643 1644 if (likely(sock != NULL)) { 1645 enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM; 1646 1647 p = &mdev->data.sbuf.rs_param_89; 1648 1649 /* initialize verify_alg and csums_alg */ 1650 memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX); 1651 1652 p->rate = cpu_to_be32(sc->rate); 1653 1654 if (apv >= 88) 1655 strcpy(p->verify_alg, mdev->sync_conf.verify_alg); 1656 if (apv >= 89) 1657 strcpy(p->csums_alg, mdev->sync_conf.csums_alg); 1658 1659 rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0); 1660 } else 1661 rv = 0; /* not ok */ 1662 1663 mutex_unlock(&mdev->data.mutex); 1664 1665 return rv; 1666 } 1667 1668 int drbd_send_protocol(struct drbd_conf *mdev) 1669 { 1670 struct p_protocol *p; 1671 int size, cf, rv; 1672 1673 size = sizeof(struct p_protocol); 1674 1675 if (mdev->agreed_pro_version >= 87) 1676 size += strlen(mdev->net_conf->integrity_alg) + 1; 1677 1678 /* we must not recurse into our own queue, 1679 * as that is blocked during handshake */ 1680 p = kmalloc(size, GFP_NOIO); 1681 if (p == NULL) 1682 return 0; 1683 1684 p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol); 1685 p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p); 1686 p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p); 1687 p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p); 1688 p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries); 1689 1690 cf = 0; 1691 if (mdev->net_conf->want_lose) 1692 cf |= CF_WANT_LOSE; 1693 if (mdev->net_conf->dry_run) { 1694 if (mdev->agreed_pro_version >= 92) 1695 cf |= CF_DRY_RUN; 1696 else { 1697 dev_err(DEV, "--dry-run is not supported by peer"); 1698 kfree(p); 1699 return 0; 1700 } 1701 } 1702 p->conn_flags = cpu_to_be32(cf); 1703 1704 if (mdev->agreed_pro_version >= 87) 1705 strcpy(p->integrity_alg, mdev->net_conf->integrity_alg); 1706 1707 rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL, 1708 (struct p_header *)p, size); 1709 kfree(p); 1710 return rv; 1711 } 1712 1713 int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags) 1714 { 1715 struct p_uuids p; 1716 int i; 1717 1718 if (!get_ldev_if_state(mdev, D_NEGOTIATING)) 1719 return 1; 1720 1721 for (i = UI_CURRENT; i < UI_SIZE; i++) 1722 p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0; 1723 1724 mdev->comm_bm_set = drbd_bm_total_weight(mdev); 1725 p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set); 1726 uuid_flags |= mdev->net_conf->want_lose ? 1 : 0; 1727 uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0; 1728 uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0; 1729 p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags); 1730 1731 put_ldev(mdev); 1732 1733 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS, 1734 (struct p_header *)&p, sizeof(p)); 1735 } 1736 1737 int drbd_send_uuids(struct drbd_conf *mdev) 1738 { 1739 return _drbd_send_uuids(mdev, 0); 1740 } 1741 1742 int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev) 1743 { 1744 return _drbd_send_uuids(mdev, 8); 1745 } 1746 1747 1748 int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val) 1749 { 1750 struct p_rs_uuid p; 1751 1752 p.uuid = cpu_to_be64(val); 1753 1754 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID, 1755 (struct p_header *)&p, sizeof(p)); 1756 } 1757 1758 int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply) 1759 { 1760 struct p_sizes p; 1761 sector_t d_size, u_size; 1762 int q_order_type; 1763 int ok; 1764 1765 if (get_ldev_if_state(mdev, D_NEGOTIATING)) { 1766 D_ASSERT(mdev->ldev->backing_bdev); 1767 d_size = drbd_get_max_capacity(mdev->ldev); 1768 u_size = mdev->ldev->dc.disk_size; 1769 q_order_type = drbd_queue_order_type(mdev); 1770 p.queue_order_type = cpu_to_be32(drbd_queue_order_type(mdev)); 1771 put_ldev(mdev); 1772 } else { 1773 d_size = 0; 1774 u_size = 0; 1775 q_order_type = QUEUE_ORDERED_NONE; 1776 } 1777 1778 p.d_size = cpu_to_be64(d_size); 1779 p.u_size = cpu_to_be64(u_size); 1780 p.c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev)); 1781 p.max_segment_size = cpu_to_be32(queue_max_segment_size(mdev->rq_queue)); 1782 p.queue_order_type = cpu_to_be32(q_order_type); 1783 1784 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES, 1785 (struct p_header *)&p, sizeof(p)); 1786 return ok; 1787 } 1788 1789 /** 1790 * drbd_send_state() - Sends the drbd state to the peer 1791 * @mdev: DRBD device. 1792 */ 1793 int drbd_send_state(struct drbd_conf *mdev) 1794 { 1795 struct socket *sock; 1796 struct p_state p; 1797 int ok = 0; 1798 1799 /* Grab state lock so we wont send state if we're in the middle 1800 * of a cluster wide state change on another thread */ 1801 drbd_state_lock(mdev); 1802 1803 mutex_lock(&mdev->data.mutex); 1804 1805 p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */ 1806 sock = mdev->data.socket; 1807 1808 if (likely(sock != NULL)) { 1809 ok = _drbd_send_cmd(mdev, sock, P_STATE, 1810 (struct p_header *)&p, sizeof(p), 0); 1811 } 1812 1813 mutex_unlock(&mdev->data.mutex); 1814 1815 drbd_state_unlock(mdev); 1816 return ok; 1817 } 1818 1819 int drbd_send_state_req(struct drbd_conf *mdev, 1820 union drbd_state mask, union drbd_state val) 1821 { 1822 struct p_req_state p; 1823 1824 p.mask = cpu_to_be32(mask.i); 1825 p.val = cpu_to_be32(val.i); 1826 1827 return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ, 1828 (struct p_header *)&p, sizeof(p)); 1829 } 1830 1831 int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode) 1832 { 1833 struct p_req_state_reply p; 1834 1835 p.retcode = cpu_to_be32(retcode); 1836 1837 return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY, 1838 (struct p_header *)&p, sizeof(p)); 1839 } 1840 1841 int fill_bitmap_rle_bits(struct drbd_conf *mdev, 1842 struct p_compressed_bm *p, 1843 struct bm_xfer_ctx *c) 1844 { 1845 struct bitstream bs; 1846 unsigned long plain_bits; 1847 unsigned long tmp; 1848 unsigned long rl; 1849 unsigned len; 1850 unsigned toggle; 1851 int bits; 1852 1853 /* may we use this feature? */ 1854 if ((mdev->sync_conf.use_rle == 0) || 1855 (mdev->agreed_pro_version < 90)) 1856 return 0; 1857 1858 if (c->bit_offset >= c->bm_bits) 1859 return 0; /* nothing to do. */ 1860 1861 /* use at most thus many bytes */ 1862 bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0); 1863 memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX); 1864 /* plain bits covered in this code string */ 1865 plain_bits = 0; 1866 1867 /* p->encoding & 0x80 stores whether the first run length is set. 1868 * bit offset is implicit. 1869 * start with toggle == 2 to be able to tell the first iteration */ 1870 toggle = 2; 1871 1872 /* see how much plain bits we can stuff into one packet 1873 * using RLE and VLI. */ 1874 do { 1875 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset) 1876 : _drbd_bm_find_next(mdev, c->bit_offset); 1877 if (tmp == -1UL) 1878 tmp = c->bm_bits; 1879 rl = tmp - c->bit_offset; 1880 1881 if (toggle == 2) { /* first iteration */ 1882 if (rl == 0) { 1883 /* the first checked bit was set, 1884 * store start value, */ 1885 DCBP_set_start(p, 1); 1886 /* but skip encoding of zero run length */ 1887 toggle = !toggle; 1888 continue; 1889 } 1890 DCBP_set_start(p, 0); 1891 } 1892 1893 /* paranoia: catch zero runlength. 1894 * can only happen if bitmap is modified while we scan it. */ 1895 if (rl == 0) { 1896 dev_err(DEV, "unexpected zero runlength while encoding bitmap " 1897 "t:%u bo:%lu\n", toggle, c->bit_offset); 1898 return -1; 1899 } 1900 1901 bits = vli_encode_bits(&bs, rl); 1902 if (bits == -ENOBUFS) /* buffer full */ 1903 break; 1904 if (bits <= 0) { 1905 dev_err(DEV, "error while encoding bitmap: %d\n", bits); 1906 return 0; 1907 } 1908 1909 toggle = !toggle; 1910 plain_bits += rl; 1911 c->bit_offset = tmp; 1912 } while (c->bit_offset < c->bm_bits); 1913 1914 len = bs.cur.b - p->code + !!bs.cur.bit; 1915 1916 if (plain_bits < (len << 3)) { 1917 /* incompressible with this method. 1918 * we need to rewind both word and bit position. */ 1919 c->bit_offset -= plain_bits; 1920 bm_xfer_ctx_bit_to_word_offset(c); 1921 c->bit_offset = c->word_offset * BITS_PER_LONG; 1922 return 0; 1923 } 1924 1925 /* RLE + VLI was able to compress it just fine. 1926 * update c->word_offset. */ 1927 bm_xfer_ctx_bit_to_word_offset(c); 1928 1929 /* store pad_bits */ 1930 DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7); 1931 1932 return len; 1933 } 1934 1935 enum { OK, FAILED, DONE } 1936 send_bitmap_rle_or_plain(struct drbd_conf *mdev, 1937 struct p_header *h, struct bm_xfer_ctx *c) 1938 { 1939 struct p_compressed_bm *p = (void*)h; 1940 unsigned long num_words; 1941 int len; 1942 int ok; 1943 1944 len = fill_bitmap_rle_bits(mdev, p, c); 1945 1946 if (len < 0) 1947 return FAILED; 1948 1949 if (len) { 1950 DCBP_set_code(p, RLE_VLI_Bits); 1951 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h, 1952 sizeof(*p) + len, 0); 1953 1954 c->packets[0]++; 1955 c->bytes[0] += sizeof(*p) + len; 1956 1957 if (c->bit_offset >= c->bm_bits) 1958 len = 0; /* DONE */ 1959 } else { 1960 /* was not compressible. 1961 * send a buffer full of plain text bits instead. */ 1962 num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset); 1963 len = num_words * sizeof(long); 1964 if (len) 1965 drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload); 1966 ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP, 1967 h, sizeof(struct p_header) + len, 0); 1968 c->word_offset += num_words; 1969 c->bit_offset = c->word_offset * BITS_PER_LONG; 1970 1971 c->packets[1]++; 1972 c->bytes[1] += sizeof(struct p_header) + len; 1973 1974 if (c->bit_offset > c->bm_bits) 1975 c->bit_offset = c->bm_bits; 1976 } 1977 ok = ok ? ((len == 0) ? DONE : OK) : FAILED; 1978 1979 if (ok == DONE) 1980 INFO_bm_xfer_stats(mdev, "send", c); 1981 return ok; 1982 } 1983 1984 /* See the comment at receive_bitmap() */ 1985 int _drbd_send_bitmap(struct drbd_conf *mdev) 1986 { 1987 struct bm_xfer_ctx c; 1988 struct p_header *p; 1989 int ret; 1990 1991 ERR_IF(!mdev->bitmap) return FALSE; 1992 1993 /* maybe we should use some per thread scratch page, 1994 * and allocate that during initial device creation? */ 1995 p = (struct p_header *) __get_free_page(GFP_NOIO); 1996 if (!p) { 1997 dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__); 1998 return FALSE; 1999 } 2000 2001 if (get_ldev(mdev)) { 2002 if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) { 2003 dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n"); 2004 drbd_bm_set_all(mdev); 2005 if (drbd_bm_write(mdev)) { 2006 /* write_bm did fail! Leave full sync flag set in Meta P_DATA 2007 * but otherwise process as per normal - need to tell other 2008 * side that a full resync is required! */ 2009 dev_err(DEV, "Failed to write bitmap to disk!\n"); 2010 } else { 2011 drbd_md_clear_flag(mdev, MDF_FULL_SYNC); 2012 drbd_md_sync(mdev); 2013 } 2014 } 2015 put_ldev(mdev); 2016 } 2017 2018 c = (struct bm_xfer_ctx) { 2019 .bm_bits = drbd_bm_bits(mdev), 2020 .bm_words = drbd_bm_words(mdev), 2021 }; 2022 2023 do { 2024 ret = send_bitmap_rle_or_plain(mdev, p, &c); 2025 } while (ret == OK); 2026 2027 free_page((unsigned long) p); 2028 return (ret == DONE); 2029 } 2030 2031 int drbd_send_bitmap(struct drbd_conf *mdev) 2032 { 2033 int err; 2034 2035 if (!drbd_get_data_sock(mdev)) 2036 return -1; 2037 err = !_drbd_send_bitmap(mdev); 2038 drbd_put_data_sock(mdev); 2039 return err; 2040 } 2041 2042 int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size) 2043 { 2044 int ok; 2045 struct p_barrier_ack p; 2046 2047 p.barrier = barrier_nr; 2048 p.set_size = cpu_to_be32(set_size); 2049 2050 if (mdev->state.conn < C_CONNECTED) 2051 return FALSE; 2052 ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK, 2053 (struct p_header *)&p, sizeof(p)); 2054 return ok; 2055 } 2056 2057 /** 2058 * _drbd_send_ack() - Sends an ack packet 2059 * @mdev: DRBD device. 2060 * @cmd: Packet command code. 2061 * @sector: sector, needs to be in big endian byte order 2062 * @blksize: size in byte, needs to be in big endian byte order 2063 * @block_id: Id, big endian byte order 2064 */ 2065 static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd, 2066 u64 sector, 2067 u32 blksize, 2068 u64 block_id) 2069 { 2070 int ok; 2071 struct p_block_ack p; 2072 2073 p.sector = sector; 2074 p.block_id = block_id; 2075 p.blksize = blksize; 2076 p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq)); 2077 2078 if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED) 2079 return FALSE; 2080 ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd, 2081 (struct p_header *)&p, sizeof(p)); 2082 return ok; 2083 } 2084 2085 int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd, 2086 struct p_data *dp) 2087 { 2088 const int header_size = sizeof(struct p_data) 2089 - sizeof(struct p_header); 2090 int data_size = ((struct p_header *)dp)->length - header_size; 2091 2092 return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size), 2093 dp->block_id); 2094 } 2095 2096 int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd, 2097 struct p_block_req *rp) 2098 { 2099 return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id); 2100 } 2101 2102 /** 2103 * drbd_send_ack() - Sends an ack packet 2104 * @mdev: DRBD device. 2105 * @cmd: Packet command code. 2106 * @e: Epoch entry. 2107 */ 2108 int drbd_send_ack(struct drbd_conf *mdev, 2109 enum drbd_packets cmd, struct drbd_epoch_entry *e) 2110 { 2111 return _drbd_send_ack(mdev, cmd, 2112 cpu_to_be64(e->sector), 2113 cpu_to_be32(e->size), 2114 e->block_id); 2115 } 2116 2117 /* This function misuses the block_id field to signal if the blocks 2118 * are is sync or not. */ 2119 int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd, 2120 sector_t sector, int blksize, u64 block_id) 2121 { 2122 return _drbd_send_ack(mdev, cmd, 2123 cpu_to_be64(sector), 2124 cpu_to_be32(blksize), 2125 cpu_to_be64(block_id)); 2126 } 2127 2128 int drbd_send_drequest(struct drbd_conf *mdev, int cmd, 2129 sector_t sector, int size, u64 block_id) 2130 { 2131 int ok; 2132 struct p_block_req p; 2133 2134 p.sector = cpu_to_be64(sector); 2135 p.block_id = block_id; 2136 p.blksize = cpu_to_be32(size); 2137 2138 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, 2139 (struct p_header *)&p, sizeof(p)); 2140 return ok; 2141 } 2142 2143 int drbd_send_drequest_csum(struct drbd_conf *mdev, 2144 sector_t sector, int size, 2145 void *digest, int digest_size, 2146 enum drbd_packets cmd) 2147 { 2148 int ok; 2149 struct p_block_req p; 2150 2151 p.sector = cpu_to_be64(sector); 2152 p.block_id = BE_DRBD_MAGIC + 0xbeef; 2153 p.blksize = cpu_to_be32(size); 2154 2155 p.head.magic = BE_DRBD_MAGIC; 2156 p.head.command = cpu_to_be16(cmd); 2157 p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size); 2158 2159 mutex_lock(&mdev->data.mutex); 2160 2161 ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0)); 2162 ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0)); 2163 2164 mutex_unlock(&mdev->data.mutex); 2165 2166 return ok; 2167 } 2168 2169 int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size) 2170 { 2171 int ok; 2172 struct p_block_req p; 2173 2174 p.sector = cpu_to_be64(sector); 2175 p.block_id = BE_DRBD_MAGIC + 0xbabe; 2176 p.blksize = cpu_to_be32(size); 2177 2178 ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST, 2179 (struct p_header *)&p, sizeof(p)); 2180 return ok; 2181 } 2182 2183 /* called on sndtimeo 2184 * returns FALSE if we should retry, 2185 * TRUE if we think connection is dead 2186 */ 2187 static int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock) 2188 { 2189 int drop_it; 2190 /* long elapsed = (long)(jiffies - mdev->last_received); */ 2191 2192 drop_it = mdev->meta.socket == sock 2193 || !mdev->asender.task 2194 || get_t_state(&mdev->asender) != Running 2195 || mdev->state.conn < C_CONNECTED; 2196 2197 if (drop_it) 2198 return TRUE; 2199 2200 drop_it = !--mdev->ko_count; 2201 if (!drop_it) { 2202 dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n", 2203 current->comm, current->pid, mdev->ko_count); 2204 request_ping(mdev); 2205 } 2206 2207 return drop_it; /* && (mdev->state == R_PRIMARY) */; 2208 } 2209 2210 /* The idea of sendpage seems to be to put some kind of reference 2211 * to the page into the skb, and to hand it over to the NIC. In 2212 * this process get_page() gets called. 2213 * 2214 * As soon as the page was really sent over the network put_page() 2215 * gets called by some part of the network layer. [ NIC driver? ] 2216 * 2217 * [ get_page() / put_page() increment/decrement the count. If count 2218 * reaches 0 the page will be freed. ] 2219 * 2220 * This works nicely with pages from FSs. 2221 * But this means that in protocol A we might signal IO completion too early! 2222 * 2223 * In order not to corrupt data during a resync we must make sure 2224 * that we do not reuse our own buffer pages (EEs) to early, therefore 2225 * we have the net_ee list. 2226 * 2227 * XFS seems to have problems, still, it submits pages with page_count == 0! 2228 * As a workaround, we disable sendpage on pages 2229 * with page_count == 0 or PageSlab. 2230 */ 2231 static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page, 2232 int offset, size_t size) 2233 { 2234 int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0); 2235 kunmap(page); 2236 if (sent == size) 2237 mdev->send_cnt += size>>9; 2238 return sent == size; 2239 } 2240 2241 static int _drbd_send_page(struct drbd_conf *mdev, struct page *page, 2242 int offset, size_t size) 2243 { 2244 mm_segment_t oldfs = get_fs(); 2245 int sent, ok; 2246 int len = size; 2247 2248 /* e.g. XFS meta- & log-data is in slab pages, which have a 2249 * page_count of 0 and/or have PageSlab() set. 2250 * we cannot use send_page for those, as that does get_page(); 2251 * put_page(); and would cause either a VM_BUG directly, or 2252 * __page_cache_release a page that would actually still be referenced 2253 * by someone, leading to some obscure delayed Oops somewhere else. */ 2254 if (disable_sendpage || (page_count(page) < 1) || PageSlab(page)) 2255 return _drbd_no_send_page(mdev, page, offset, size); 2256 2257 drbd_update_congested(mdev); 2258 set_fs(KERNEL_DS); 2259 do { 2260 sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page, 2261 offset, len, 2262 MSG_NOSIGNAL); 2263 if (sent == -EAGAIN) { 2264 if (we_should_drop_the_connection(mdev, 2265 mdev->data.socket)) 2266 break; 2267 else 2268 continue; 2269 } 2270 if (sent <= 0) { 2271 dev_warn(DEV, "%s: size=%d len=%d sent=%d\n", 2272 __func__, (int)size, len, sent); 2273 break; 2274 } 2275 len -= sent; 2276 offset += sent; 2277 } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/); 2278 set_fs(oldfs); 2279 clear_bit(NET_CONGESTED, &mdev->flags); 2280 2281 ok = (len == 0); 2282 if (likely(ok)) 2283 mdev->send_cnt += size>>9; 2284 return ok; 2285 } 2286 2287 static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio) 2288 { 2289 struct bio_vec *bvec; 2290 int i; 2291 __bio_for_each_segment(bvec, bio, i, 0) { 2292 if (!_drbd_no_send_page(mdev, bvec->bv_page, 2293 bvec->bv_offset, bvec->bv_len)) 2294 return 0; 2295 } 2296 return 1; 2297 } 2298 2299 static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio) 2300 { 2301 struct bio_vec *bvec; 2302 int i; 2303 __bio_for_each_segment(bvec, bio, i, 0) { 2304 if (!_drbd_send_page(mdev, bvec->bv_page, 2305 bvec->bv_offset, bvec->bv_len)) 2306 return 0; 2307 } 2308 2309 return 1; 2310 } 2311 2312 /* Used to send write requests 2313 * R_PRIMARY -> Peer (P_DATA) 2314 */ 2315 int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req) 2316 { 2317 int ok = 1; 2318 struct p_data p; 2319 unsigned int dp_flags = 0; 2320 void *dgb; 2321 int dgs; 2322 2323 if (!drbd_get_data_sock(mdev)) 2324 return 0; 2325 2326 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ? 2327 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0; 2328 2329 p.head.magic = BE_DRBD_MAGIC; 2330 p.head.command = cpu_to_be16(P_DATA); 2331 p.head.length = 2332 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size); 2333 2334 p.sector = cpu_to_be64(req->sector); 2335 p.block_id = (unsigned long)req; 2336 p.seq_num = cpu_to_be32(req->seq_num = 2337 atomic_add_return(1, &mdev->packet_seq)); 2338 dp_flags = 0; 2339 2340 /* NOTE: no need to check if barriers supported here as we would 2341 * not pass the test in make_request_common in that case 2342 */ 2343 if (bio_rw_flagged(req->master_bio, BIO_RW_BARRIER)) { 2344 dev_err(DEV, "ASSERT FAILED would have set DP_HARDBARRIER\n"); 2345 /* dp_flags |= DP_HARDBARRIER; */ 2346 } 2347 if (bio_rw_flagged(req->master_bio, BIO_RW_SYNCIO)) 2348 dp_flags |= DP_RW_SYNC; 2349 /* for now handle SYNCIO and UNPLUG 2350 * as if they still were one and the same flag */ 2351 if (bio_rw_flagged(req->master_bio, BIO_RW_UNPLUG)) 2352 dp_flags |= DP_RW_SYNC; 2353 if (mdev->state.conn >= C_SYNC_SOURCE && 2354 mdev->state.conn <= C_PAUSED_SYNC_T) 2355 dp_flags |= DP_MAY_SET_IN_SYNC; 2356 2357 p.dp_flags = cpu_to_be32(dp_flags); 2358 set_bit(UNPLUG_REMOTE, &mdev->flags); 2359 ok = (sizeof(p) == 2360 drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE)); 2361 if (ok && dgs) { 2362 dgb = mdev->int_dig_out; 2363 drbd_csum(mdev, mdev->integrity_w_tfm, req->master_bio, dgb); 2364 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE); 2365 } 2366 if (ok) { 2367 if (mdev->net_conf->wire_protocol == DRBD_PROT_A) 2368 ok = _drbd_send_bio(mdev, req->master_bio); 2369 else 2370 ok = _drbd_send_zc_bio(mdev, req->master_bio); 2371 } 2372 2373 drbd_put_data_sock(mdev); 2374 return ok; 2375 } 2376 2377 /* answer packet, used to send data back for read requests: 2378 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY) 2379 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY) 2380 */ 2381 int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd, 2382 struct drbd_epoch_entry *e) 2383 { 2384 int ok; 2385 struct p_data p; 2386 void *dgb; 2387 int dgs; 2388 2389 dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ? 2390 crypto_hash_digestsize(mdev->integrity_w_tfm) : 0; 2391 2392 p.head.magic = BE_DRBD_MAGIC; 2393 p.head.command = cpu_to_be16(cmd); 2394 p.head.length = 2395 cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size); 2396 2397 p.sector = cpu_to_be64(e->sector); 2398 p.block_id = e->block_id; 2399 /* p.seq_num = 0; No sequence numbers here.. */ 2400 2401 /* Only called by our kernel thread. 2402 * This one may be interrupted by DRBD_SIG and/or DRBD_SIGKILL 2403 * in response to admin command or module unload. 2404 */ 2405 if (!drbd_get_data_sock(mdev)) 2406 return 0; 2407 2408 ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, 2409 sizeof(p), MSG_MORE); 2410 if (ok && dgs) { 2411 dgb = mdev->int_dig_out; 2412 drbd_csum(mdev, mdev->integrity_w_tfm, e->private_bio, dgb); 2413 ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE); 2414 } 2415 if (ok) 2416 ok = _drbd_send_zc_bio(mdev, e->private_bio); 2417 2418 drbd_put_data_sock(mdev); 2419 return ok; 2420 } 2421 2422 /* 2423 drbd_send distinguishes two cases: 2424 2425 Packets sent via the data socket "sock" 2426 and packets sent via the meta data socket "msock" 2427 2428 sock msock 2429 -----------------+-------------------------+------------------------------ 2430 timeout conf.timeout / 2 conf.timeout / 2 2431 timeout action send a ping via msock Abort communication 2432 and close all sockets 2433 */ 2434 2435 /* 2436 * you must have down()ed the appropriate [m]sock_mutex elsewhere! 2437 */ 2438 int drbd_send(struct drbd_conf *mdev, struct socket *sock, 2439 void *buf, size_t size, unsigned msg_flags) 2440 { 2441 struct kvec iov; 2442 struct msghdr msg; 2443 int rv, sent = 0; 2444 2445 if (!sock) 2446 return -1000; 2447 2448 /* THINK if (signal_pending) return ... ? */ 2449 2450 iov.iov_base = buf; 2451 iov.iov_len = size; 2452 2453 msg.msg_name = NULL; 2454 msg.msg_namelen = 0; 2455 msg.msg_control = NULL; 2456 msg.msg_controllen = 0; 2457 msg.msg_flags = msg_flags | MSG_NOSIGNAL; 2458 2459 if (sock == mdev->data.socket) { 2460 mdev->ko_count = mdev->net_conf->ko_count; 2461 drbd_update_congested(mdev); 2462 } 2463 do { 2464 /* STRANGE 2465 * tcp_sendmsg does _not_ use its size parameter at all ? 2466 * 2467 * -EAGAIN on timeout, -EINTR on signal. 2468 */ 2469 /* THINK 2470 * do we need to block DRBD_SIG if sock == &meta.socket ?? 2471 * otherwise wake_asender() might interrupt some send_*Ack ! 2472 */ 2473 rv = kernel_sendmsg(sock, &msg, &iov, 1, size); 2474 if (rv == -EAGAIN) { 2475 if (we_should_drop_the_connection(mdev, sock)) 2476 break; 2477 else 2478 continue; 2479 } 2480 D_ASSERT(rv != 0); 2481 if (rv == -EINTR) { 2482 flush_signals(current); 2483 rv = 0; 2484 } 2485 if (rv < 0) 2486 break; 2487 sent += rv; 2488 iov.iov_base += rv; 2489 iov.iov_len -= rv; 2490 } while (sent < size); 2491 2492 if (sock == mdev->data.socket) 2493 clear_bit(NET_CONGESTED, &mdev->flags); 2494 2495 if (rv <= 0) { 2496 if (rv != -EAGAIN) { 2497 dev_err(DEV, "%s_sendmsg returned %d\n", 2498 sock == mdev->meta.socket ? "msock" : "sock", 2499 rv); 2500 drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE)); 2501 } else 2502 drbd_force_state(mdev, NS(conn, C_TIMEOUT)); 2503 } 2504 2505 return sent; 2506 } 2507 2508 static int drbd_open(struct block_device *bdev, fmode_t mode) 2509 { 2510 struct drbd_conf *mdev = bdev->bd_disk->private_data; 2511 unsigned long flags; 2512 int rv = 0; 2513 2514 spin_lock_irqsave(&mdev->req_lock, flags); 2515 /* to have a stable mdev->state.role 2516 * and no race with updating open_cnt */ 2517 2518 if (mdev->state.role != R_PRIMARY) { 2519 if (mode & FMODE_WRITE) 2520 rv = -EROFS; 2521 else if (!allow_oos) 2522 rv = -EMEDIUMTYPE; 2523 } 2524 2525 if (!rv) 2526 mdev->open_cnt++; 2527 spin_unlock_irqrestore(&mdev->req_lock, flags); 2528 2529 return rv; 2530 } 2531 2532 static int drbd_release(struct gendisk *gd, fmode_t mode) 2533 { 2534 struct drbd_conf *mdev = gd->private_data; 2535 mdev->open_cnt--; 2536 return 0; 2537 } 2538 2539 static void drbd_unplug_fn(struct request_queue *q) 2540 { 2541 struct drbd_conf *mdev = q->queuedata; 2542 2543 /* unplug FIRST */ 2544 spin_lock_irq(q->queue_lock); 2545 blk_remove_plug(q); 2546 spin_unlock_irq(q->queue_lock); 2547 2548 /* only if connected */ 2549 spin_lock_irq(&mdev->req_lock); 2550 if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) { 2551 D_ASSERT(mdev->state.role == R_PRIMARY); 2552 if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) { 2553 /* add to the data.work queue, 2554 * unless already queued. 2555 * XXX this might be a good addition to drbd_queue_work 2556 * anyways, to detect "double queuing" ... */ 2557 if (list_empty(&mdev->unplug_work.list)) 2558 drbd_queue_work(&mdev->data.work, 2559 &mdev->unplug_work); 2560 } 2561 } 2562 spin_unlock_irq(&mdev->req_lock); 2563 2564 if (mdev->state.disk >= D_INCONSISTENT) 2565 drbd_kick_lo(mdev); 2566 } 2567 2568 static void drbd_set_defaults(struct drbd_conf *mdev) 2569 { 2570 mdev->sync_conf.after = DRBD_AFTER_DEF; 2571 mdev->sync_conf.rate = DRBD_RATE_DEF; 2572 mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF; 2573 mdev->state = (union drbd_state) { 2574 { .role = R_SECONDARY, 2575 .peer = R_UNKNOWN, 2576 .conn = C_STANDALONE, 2577 .disk = D_DISKLESS, 2578 .pdsk = D_UNKNOWN, 2579 .susp = 0 2580 } }; 2581 } 2582 2583 void drbd_init_set_defaults(struct drbd_conf *mdev) 2584 { 2585 /* the memset(,0,) did most of this. 2586 * note: only assignments, no allocation in here */ 2587 2588 drbd_set_defaults(mdev); 2589 2590 /* for now, we do NOT yet support it, 2591 * even though we start some framework 2592 * to eventually support barriers */ 2593 set_bit(NO_BARRIER_SUPP, &mdev->flags); 2594 2595 atomic_set(&mdev->ap_bio_cnt, 0); 2596 atomic_set(&mdev->ap_pending_cnt, 0); 2597 atomic_set(&mdev->rs_pending_cnt, 0); 2598 atomic_set(&mdev->unacked_cnt, 0); 2599 atomic_set(&mdev->local_cnt, 0); 2600 atomic_set(&mdev->net_cnt, 0); 2601 atomic_set(&mdev->packet_seq, 0); 2602 atomic_set(&mdev->pp_in_use, 0); 2603 2604 mutex_init(&mdev->md_io_mutex); 2605 mutex_init(&mdev->data.mutex); 2606 mutex_init(&mdev->meta.mutex); 2607 sema_init(&mdev->data.work.s, 0); 2608 sema_init(&mdev->meta.work.s, 0); 2609 mutex_init(&mdev->state_mutex); 2610 2611 spin_lock_init(&mdev->data.work.q_lock); 2612 spin_lock_init(&mdev->meta.work.q_lock); 2613 2614 spin_lock_init(&mdev->al_lock); 2615 spin_lock_init(&mdev->req_lock); 2616 spin_lock_init(&mdev->peer_seq_lock); 2617 spin_lock_init(&mdev->epoch_lock); 2618 2619 INIT_LIST_HEAD(&mdev->active_ee); 2620 INIT_LIST_HEAD(&mdev->sync_ee); 2621 INIT_LIST_HEAD(&mdev->done_ee); 2622 INIT_LIST_HEAD(&mdev->read_ee); 2623 INIT_LIST_HEAD(&mdev->net_ee); 2624 INIT_LIST_HEAD(&mdev->resync_reads); 2625 INIT_LIST_HEAD(&mdev->data.work.q); 2626 INIT_LIST_HEAD(&mdev->meta.work.q); 2627 INIT_LIST_HEAD(&mdev->resync_work.list); 2628 INIT_LIST_HEAD(&mdev->unplug_work.list); 2629 INIT_LIST_HEAD(&mdev->md_sync_work.list); 2630 INIT_LIST_HEAD(&mdev->bm_io_work.w.list); 2631 mdev->resync_work.cb = w_resync_inactive; 2632 mdev->unplug_work.cb = w_send_write_hint; 2633 mdev->md_sync_work.cb = w_md_sync; 2634 mdev->bm_io_work.w.cb = w_bitmap_io; 2635 init_timer(&mdev->resync_timer); 2636 init_timer(&mdev->md_sync_timer); 2637 mdev->resync_timer.function = resync_timer_fn; 2638 mdev->resync_timer.data = (unsigned long) mdev; 2639 mdev->md_sync_timer.function = md_sync_timer_fn; 2640 mdev->md_sync_timer.data = (unsigned long) mdev; 2641 2642 init_waitqueue_head(&mdev->misc_wait); 2643 init_waitqueue_head(&mdev->state_wait); 2644 init_waitqueue_head(&mdev->ee_wait); 2645 init_waitqueue_head(&mdev->al_wait); 2646 init_waitqueue_head(&mdev->seq_wait); 2647 2648 drbd_thread_init(mdev, &mdev->receiver, drbdd_init); 2649 drbd_thread_init(mdev, &mdev->worker, drbd_worker); 2650 drbd_thread_init(mdev, &mdev->asender, drbd_asender); 2651 2652 mdev->agreed_pro_version = PRO_VERSION_MAX; 2653 mdev->write_ordering = WO_bio_barrier; 2654 mdev->resync_wenr = LC_FREE; 2655 } 2656 2657 void drbd_mdev_cleanup(struct drbd_conf *mdev) 2658 { 2659 if (mdev->receiver.t_state != None) 2660 dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n", 2661 mdev->receiver.t_state); 2662 2663 /* no need to lock it, I'm the only thread alive */ 2664 if (atomic_read(&mdev->current_epoch->epoch_size) != 0) 2665 dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size)); 2666 mdev->al_writ_cnt = 2667 mdev->bm_writ_cnt = 2668 mdev->read_cnt = 2669 mdev->recv_cnt = 2670 mdev->send_cnt = 2671 mdev->writ_cnt = 2672 mdev->p_size = 2673 mdev->rs_start = 2674 mdev->rs_total = 2675 mdev->rs_failed = 2676 mdev->rs_mark_left = 2677 mdev->rs_mark_time = 0; 2678 D_ASSERT(mdev->net_conf == NULL); 2679 2680 drbd_set_my_capacity(mdev, 0); 2681 if (mdev->bitmap) { 2682 /* maybe never allocated. */ 2683 drbd_bm_resize(mdev, 0); 2684 drbd_bm_cleanup(mdev); 2685 } 2686 2687 drbd_free_resources(mdev); 2688 2689 /* 2690 * currently we drbd_init_ee only on module load, so 2691 * we may do drbd_release_ee only on module unload! 2692 */ 2693 D_ASSERT(list_empty(&mdev->active_ee)); 2694 D_ASSERT(list_empty(&mdev->sync_ee)); 2695 D_ASSERT(list_empty(&mdev->done_ee)); 2696 D_ASSERT(list_empty(&mdev->read_ee)); 2697 D_ASSERT(list_empty(&mdev->net_ee)); 2698 D_ASSERT(list_empty(&mdev->resync_reads)); 2699 D_ASSERT(list_empty(&mdev->data.work.q)); 2700 D_ASSERT(list_empty(&mdev->meta.work.q)); 2701 D_ASSERT(list_empty(&mdev->resync_work.list)); 2702 D_ASSERT(list_empty(&mdev->unplug_work.list)); 2703 2704 } 2705 2706 2707 static void drbd_destroy_mempools(void) 2708 { 2709 struct page *page; 2710 2711 while (drbd_pp_pool) { 2712 page = drbd_pp_pool; 2713 drbd_pp_pool = (struct page *)page_private(page); 2714 __free_page(page); 2715 drbd_pp_vacant--; 2716 } 2717 2718 /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */ 2719 2720 if (drbd_ee_mempool) 2721 mempool_destroy(drbd_ee_mempool); 2722 if (drbd_request_mempool) 2723 mempool_destroy(drbd_request_mempool); 2724 if (drbd_ee_cache) 2725 kmem_cache_destroy(drbd_ee_cache); 2726 if (drbd_request_cache) 2727 kmem_cache_destroy(drbd_request_cache); 2728 if (drbd_bm_ext_cache) 2729 kmem_cache_destroy(drbd_bm_ext_cache); 2730 if (drbd_al_ext_cache) 2731 kmem_cache_destroy(drbd_al_ext_cache); 2732 2733 drbd_ee_mempool = NULL; 2734 drbd_request_mempool = NULL; 2735 drbd_ee_cache = NULL; 2736 drbd_request_cache = NULL; 2737 drbd_bm_ext_cache = NULL; 2738 drbd_al_ext_cache = NULL; 2739 2740 return; 2741 } 2742 2743 static int drbd_create_mempools(void) 2744 { 2745 struct page *page; 2746 const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count; 2747 int i; 2748 2749 /* prepare our caches and mempools */ 2750 drbd_request_mempool = NULL; 2751 drbd_ee_cache = NULL; 2752 drbd_request_cache = NULL; 2753 drbd_bm_ext_cache = NULL; 2754 drbd_al_ext_cache = NULL; 2755 drbd_pp_pool = NULL; 2756 2757 /* caches */ 2758 drbd_request_cache = kmem_cache_create( 2759 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL); 2760 if (drbd_request_cache == NULL) 2761 goto Enomem; 2762 2763 drbd_ee_cache = kmem_cache_create( 2764 "drbd_ee", sizeof(struct drbd_epoch_entry), 0, 0, NULL); 2765 if (drbd_ee_cache == NULL) 2766 goto Enomem; 2767 2768 drbd_bm_ext_cache = kmem_cache_create( 2769 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL); 2770 if (drbd_bm_ext_cache == NULL) 2771 goto Enomem; 2772 2773 drbd_al_ext_cache = kmem_cache_create( 2774 "drbd_al", sizeof(struct lc_element), 0, 0, NULL); 2775 if (drbd_al_ext_cache == NULL) 2776 goto Enomem; 2777 2778 /* mempools */ 2779 drbd_request_mempool = mempool_create(number, 2780 mempool_alloc_slab, mempool_free_slab, drbd_request_cache); 2781 if (drbd_request_mempool == NULL) 2782 goto Enomem; 2783 2784 drbd_ee_mempool = mempool_create(number, 2785 mempool_alloc_slab, mempool_free_slab, drbd_ee_cache); 2786 if (drbd_request_mempool == NULL) 2787 goto Enomem; 2788 2789 /* drbd's page pool */ 2790 spin_lock_init(&drbd_pp_lock); 2791 2792 for (i = 0; i < number; i++) { 2793 page = alloc_page(GFP_HIGHUSER); 2794 if (!page) 2795 goto Enomem; 2796 set_page_private(page, (unsigned long)drbd_pp_pool); 2797 drbd_pp_pool = page; 2798 } 2799 drbd_pp_vacant = number; 2800 2801 return 0; 2802 2803 Enomem: 2804 drbd_destroy_mempools(); /* in case we allocated some */ 2805 return -ENOMEM; 2806 } 2807 2808 static int drbd_notify_sys(struct notifier_block *this, unsigned long code, 2809 void *unused) 2810 { 2811 /* just so we have it. you never know what interesting things we 2812 * might want to do here some day... 2813 */ 2814 2815 return NOTIFY_DONE; 2816 } 2817 2818 static struct notifier_block drbd_notifier = { 2819 .notifier_call = drbd_notify_sys, 2820 }; 2821 2822 static void drbd_release_ee_lists(struct drbd_conf *mdev) 2823 { 2824 int rr; 2825 2826 rr = drbd_release_ee(mdev, &mdev->active_ee); 2827 if (rr) 2828 dev_err(DEV, "%d EEs in active list found!\n", rr); 2829 2830 rr = drbd_release_ee(mdev, &mdev->sync_ee); 2831 if (rr) 2832 dev_err(DEV, "%d EEs in sync list found!\n", rr); 2833 2834 rr = drbd_release_ee(mdev, &mdev->read_ee); 2835 if (rr) 2836 dev_err(DEV, "%d EEs in read list found!\n", rr); 2837 2838 rr = drbd_release_ee(mdev, &mdev->done_ee); 2839 if (rr) 2840 dev_err(DEV, "%d EEs in done list found!\n", rr); 2841 2842 rr = drbd_release_ee(mdev, &mdev->net_ee); 2843 if (rr) 2844 dev_err(DEV, "%d EEs in net list found!\n", rr); 2845 } 2846 2847 /* caution. no locking. 2848 * currently only used from module cleanup code. */ 2849 static void drbd_delete_device(unsigned int minor) 2850 { 2851 struct drbd_conf *mdev = minor_to_mdev(minor); 2852 2853 if (!mdev) 2854 return; 2855 2856 /* paranoia asserts */ 2857 if (mdev->open_cnt != 0) 2858 dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt, 2859 __FILE__ , __LINE__); 2860 2861 ERR_IF (!list_empty(&mdev->data.work.q)) { 2862 struct list_head *lp; 2863 list_for_each(lp, &mdev->data.work.q) { 2864 dev_err(DEV, "lp = %p\n", lp); 2865 } 2866 }; 2867 /* end paranoia asserts */ 2868 2869 del_gendisk(mdev->vdisk); 2870 2871 /* cleanup stuff that may have been allocated during 2872 * device (re-)configuration or state changes */ 2873 2874 if (mdev->this_bdev) 2875 bdput(mdev->this_bdev); 2876 2877 drbd_free_resources(mdev); 2878 2879 drbd_release_ee_lists(mdev); 2880 2881 /* should be free'd on disconnect? */ 2882 kfree(mdev->ee_hash); 2883 /* 2884 mdev->ee_hash_s = 0; 2885 mdev->ee_hash = NULL; 2886 */ 2887 2888 lc_destroy(mdev->act_log); 2889 lc_destroy(mdev->resync); 2890 2891 kfree(mdev->p_uuid); 2892 /* mdev->p_uuid = NULL; */ 2893 2894 kfree(mdev->int_dig_out); 2895 kfree(mdev->int_dig_in); 2896 kfree(mdev->int_dig_vv); 2897 2898 /* cleanup the rest that has been 2899 * allocated from drbd_new_device 2900 * and actually free the mdev itself */ 2901 drbd_free_mdev(mdev); 2902 } 2903 2904 static void drbd_cleanup(void) 2905 { 2906 unsigned int i; 2907 2908 unregister_reboot_notifier(&drbd_notifier); 2909 2910 drbd_nl_cleanup(); 2911 2912 if (minor_table) { 2913 if (drbd_proc) 2914 remove_proc_entry("drbd", NULL); 2915 i = minor_count; 2916 while (i--) 2917 drbd_delete_device(i); 2918 drbd_destroy_mempools(); 2919 } 2920 2921 kfree(minor_table); 2922 2923 unregister_blkdev(DRBD_MAJOR, "drbd"); 2924 2925 printk(KERN_INFO "drbd: module cleanup done.\n"); 2926 } 2927 2928 /** 2929 * drbd_congested() - Callback for pdflush 2930 * @congested_data: User data 2931 * @bdi_bits: Bits pdflush is currently interested in 2932 * 2933 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested. 2934 */ 2935 static int drbd_congested(void *congested_data, int bdi_bits) 2936 { 2937 struct drbd_conf *mdev = congested_data; 2938 struct request_queue *q; 2939 char reason = '-'; 2940 int r = 0; 2941 2942 if (!__inc_ap_bio_cond(mdev)) { 2943 /* DRBD has frozen IO */ 2944 r = bdi_bits; 2945 reason = 'd'; 2946 goto out; 2947 } 2948 2949 if (get_ldev(mdev)) { 2950 q = bdev_get_queue(mdev->ldev->backing_bdev); 2951 r = bdi_congested(&q->backing_dev_info, bdi_bits); 2952 put_ldev(mdev); 2953 if (r) 2954 reason = 'b'; 2955 } 2956 2957 if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) { 2958 r |= (1 << BDI_async_congested); 2959 reason = reason == 'b' ? 'a' : 'n'; 2960 } 2961 2962 out: 2963 mdev->congestion_reason = reason; 2964 return r; 2965 } 2966 2967 struct drbd_conf *drbd_new_device(unsigned int minor) 2968 { 2969 struct drbd_conf *mdev; 2970 struct gendisk *disk; 2971 struct request_queue *q; 2972 2973 /* GFP_KERNEL, we are outside of all write-out paths */ 2974 mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL); 2975 if (!mdev) 2976 return NULL; 2977 if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL)) 2978 goto out_no_cpumask; 2979 2980 mdev->minor = minor; 2981 2982 drbd_init_set_defaults(mdev); 2983 2984 q = blk_alloc_queue(GFP_KERNEL); 2985 if (!q) 2986 goto out_no_q; 2987 mdev->rq_queue = q; 2988 q->queuedata = mdev; 2989 2990 disk = alloc_disk(1); 2991 if (!disk) 2992 goto out_no_disk; 2993 mdev->vdisk = disk; 2994 2995 set_disk_ro(disk, TRUE); 2996 2997 disk->queue = q; 2998 disk->major = DRBD_MAJOR; 2999 disk->first_minor = minor; 3000 disk->fops = &drbd_ops; 3001 sprintf(disk->disk_name, "drbd%d", minor); 3002 disk->private_data = mdev; 3003 3004 mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor)); 3005 /* we have no partitions. we contain only ourselves. */ 3006 mdev->this_bdev->bd_contains = mdev->this_bdev; 3007 3008 q->backing_dev_info.congested_fn = drbd_congested; 3009 q->backing_dev_info.congested_data = mdev; 3010 3011 blk_queue_make_request(q, drbd_make_request_26); 3012 blk_queue_max_segment_size(q, DRBD_MAX_SEGMENT_SIZE); 3013 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY); 3014 blk_queue_merge_bvec(q, drbd_merge_bvec); 3015 q->queue_lock = &mdev->req_lock; /* needed since we use */ 3016 /* plugging on a queue, that actually has no requests! */ 3017 q->unplug_fn = drbd_unplug_fn; 3018 3019 mdev->md_io_page = alloc_page(GFP_KERNEL); 3020 if (!mdev->md_io_page) 3021 goto out_no_io_page; 3022 3023 if (drbd_bm_init(mdev)) 3024 goto out_no_bitmap; 3025 /* no need to lock access, we are still initializing this minor device. */ 3026 if (!tl_init(mdev)) 3027 goto out_no_tl; 3028 3029 mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL); 3030 if (!mdev->app_reads_hash) 3031 goto out_no_app_reads; 3032 3033 mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL); 3034 if (!mdev->current_epoch) 3035 goto out_no_epoch; 3036 3037 INIT_LIST_HEAD(&mdev->current_epoch->list); 3038 mdev->epochs = 1; 3039 3040 return mdev; 3041 3042 /* out_whatever_else: 3043 kfree(mdev->current_epoch); */ 3044 out_no_epoch: 3045 kfree(mdev->app_reads_hash); 3046 out_no_app_reads: 3047 tl_cleanup(mdev); 3048 out_no_tl: 3049 drbd_bm_cleanup(mdev); 3050 out_no_bitmap: 3051 __free_page(mdev->md_io_page); 3052 out_no_io_page: 3053 put_disk(disk); 3054 out_no_disk: 3055 blk_cleanup_queue(q); 3056 out_no_q: 3057 free_cpumask_var(mdev->cpu_mask); 3058 out_no_cpumask: 3059 kfree(mdev); 3060 return NULL; 3061 } 3062 3063 /* counterpart of drbd_new_device. 3064 * last part of drbd_delete_device. */ 3065 void drbd_free_mdev(struct drbd_conf *mdev) 3066 { 3067 kfree(mdev->current_epoch); 3068 kfree(mdev->app_reads_hash); 3069 tl_cleanup(mdev); 3070 if (mdev->bitmap) /* should no longer be there. */ 3071 drbd_bm_cleanup(mdev); 3072 __free_page(mdev->md_io_page); 3073 put_disk(mdev->vdisk); 3074 blk_cleanup_queue(mdev->rq_queue); 3075 free_cpumask_var(mdev->cpu_mask); 3076 kfree(mdev); 3077 } 3078 3079 3080 int __init drbd_init(void) 3081 { 3082 int err; 3083 3084 if (sizeof(struct p_handshake) != 80) { 3085 printk(KERN_ERR 3086 "drbd: never change the size or layout " 3087 "of the HandShake packet.\n"); 3088 return -EINVAL; 3089 } 3090 3091 if (1 > minor_count || minor_count > 255) { 3092 printk(KERN_ERR 3093 "drbd: invalid minor_count (%d)\n", minor_count); 3094 #ifdef MODULE 3095 return -EINVAL; 3096 #else 3097 minor_count = 8; 3098 #endif 3099 } 3100 3101 err = drbd_nl_init(); 3102 if (err) 3103 return err; 3104 3105 err = register_blkdev(DRBD_MAJOR, "drbd"); 3106 if (err) { 3107 printk(KERN_ERR 3108 "drbd: unable to register block device major %d\n", 3109 DRBD_MAJOR); 3110 return err; 3111 } 3112 3113 register_reboot_notifier(&drbd_notifier); 3114 3115 /* 3116 * allocate all necessary structs 3117 */ 3118 err = -ENOMEM; 3119 3120 init_waitqueue_head(&drbd_pp_wait); 3121 3122 drbd_proc = NULL; /* play safe for drbd_cleanup */ 3123 minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count, 3124 GFP_KERNEL); 3125 if (!minor_table) 3126 goto Enomem; 3127 3128 err = drbd_create_mempools(); 3129 if (err) 3130 goto Enomem; 3131 3132 drbd_proc = proc_create("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops); 3133 if (!drbd_proc) { 3134 printk(KERN_ERR "drbd: unable to register proc file\n"); 3135 goto Enomem; 3136 } 3137 3138 rwlock_init(&global_state_lock); 3139 3140 printk(KERN_INFO "drbd: initialized. " 3141 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n", 3142 API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX); 3143 printk(KERN_INFO "drbd: %s\n", drbd_buildtag()); 3144 printk(KERN_INFO "drbd: registered as block device major %d\n", 3145 DRBD_MAJOR); 3146 printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table); 3147 3148 return 0; /* Success! */ 3149 3150 Enomem: 3151 drbd_cleanup(); 3152 if (err == -ENOMEM) 3153 /* currently always the case */ 3154 printk(KERN_ERR "drbd: ran out of memory\n"); 3155 else 3156 printk(KERN_ERR "drbd: initialization failure\n"); 3157 return err; 3158 } 3159 3160 void drbd_free_bc(struct drbd_backing_dev *ldev) 3161 { 3162 if (ldev == NULL) 3163 return; 3164 3165 bd_release(ldev->backing_bdev); 3166 bd_release(ldev->md_bdev); 3167 3168 fput(ldev->lo_file); 3169 fput(ldev->md_file); 3170 3171 kfree(ldev); 3172 } 3173 3174 void drbd_free_sock(struct drbd_conf *mdev) 3175 { 3176 if (mdev->data.socket) { 3177 mutex_lock(&mdev->data.mutex); 3178 kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR); 3179 sock_release(mdev->data.socket); 3180 mdev->data.socket = NULL; 3181 mutex_unlock(&mdev->data.mutex); 3182 } 3183 if (mdev->meta.socket) { 3184 mutex_lock(&mdev->meta.mutex); 3185 kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR); 3186 sock_release(mdev->meta.socket); 3187 mdev->meta.socket = NULL; 3188 mutex_unlock(&mdev->meta.mutex); 3189 } 3190 } 3191 3192 3193 void drbd_free_resources(struct drbd_conf *mdev) 3194 { 3195 crypto_free_hash(mdev->csums_tfm); 3196 mdev->csums_tfm = NULL; 3197 crypto_free_hash(mdev->verify_tfm); 3198 mdev->verify_tfm = NULL; 3199 crypto_free_hash(mdev->cram_hmac_tfm); 3200 mdev->cram_hmac_tfm = NULL; 3201 crypto_free_hash(mdev->integrity_w_tfm); 3202 mdev->integrity_w_tfm = NULL; 3203 crypto_free_hash(mdev->integrity_r_tfm); 3204 mdev->integrity_r_tfm = NULL; 3205 3206 drbd_free_sock(mdev); 3207 3208 __no_warn(local, 3209 drbd_free_bc(mdev->ldev); 3210 mdev->ldev = NULL;); 3211 } 3212 3213 /* meta data management */ 3214 3215 struct meta_data_on_disk { 3216 u64 la_size; /* last agreed size. */ 3217 u64 uuid[UI_SIZE]; /* UUIDs. */ 3218 u64 device_uuid; 3219 u64 reserved_u64_1; 3220 u32 flags; /* MDF */ 3221 u32 magic; 3222 u32 md_size_sect; 3223 u32 al_offset; /* offset to this block */ 3224 u32 al_nr_extents; /* important for restoring the AL */ 3225 /* `-- act_log->nr_elements <-- sync_conf.al_extents */ 3226 u32 bm_offset; /* offset to the bitmap, from here */ 3227 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */ 3228 u32 reserved_u32[4]; 3229 3230 } __packed; 3231 3232 /** 3233 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set 3234 * @mdev: DRBD device. 3235 */ 3236 void drbd_md_sync(struct drbd_conf *mdev) 3237 { 3238 struct meta_data_on_disk *buffer; 3239 sector_t sector; 3240 int i; 3241 3242 if (!test_and_clear_bit(MD_DIRTY, &mdev->flags)) 3243 return; 3244 del_timer(&mdev->md_sync_timer); 3245 3246 /* We use here D_FAILED and not D_ATTACHING because we try to write 3247 * metadata even if we detach due to a disk failure! */ 3248 if (!get_ldev_if_state(mdev, D_FAILED)) 3249 return; 3250 3251 mutex_lock(&mdev->md_io_mutex); 3252 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page); 3253 memset(buffer, 0, 512); 3254 3255 buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev)); 3256 for (i = UI_CURRENT; i < UI_SIZE; i++) 3257 buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]); 3258 buffer->flags = cpu_to_be32(mdev->ldev->md.flags); 3259 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC); 3260 3261 buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect); 3262 buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset); 3263 buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements); 3264 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE); 3265 buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid); 3266 3267 buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset); 3268 3269 D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset); 3270 sector = mdev->ldev->md.md_offset; 3271 3272 if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) { 3273 clear_bit(MD_DIRTY, &mdev->flags); 3274 } else { 3275 /* this was a try anyways ... */ 3276 dev_err(DEV, "meta data update failed!\n"); 3277 3278 drbd_chk_io_error(mdev, 1, TRUE); 3279 } 3280 3281 /* Update mdev->ldev->md.la_size_sect, 3282 * since we updated it on metadata. */ 3283 mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev); 3284 3285 mutex_unlock(&mdev->md_io_mutex); 3286 put_ldev(mdev); 3287 } 3288 3289 /** 3290 * drbd_md_read() - Reads in the meta data super block 3291 * @mdev: DRBD device. 3292 * @bdev: Device from which the meta data should be read in. 3293 * 3294 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case 3295 * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID. 3296 */ 3297 int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev) 3298 { 3299 struct meta_data_on_disk *buffer; 3300 int i, rv = NO_ERROR; 3301 3302 if (!get_ldev_if_state(mdev, D_ATTACHING)) 3303 return ERR_IO_MD_DISK; 3304 3305 mutex_lock(&mdev->md_io_mutex); 3306 buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page); 3307 3308 if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) { 3309 /* NOTE: cant do normal error processing here as this is 3310 called BEFORE disk is attached */ 3311 dev_err(DEV, "Error while reading metadata.\n"); 3312 rv = ERR_IO_MD_DISK; 3313 goto err; 3314 } 3315 3316 if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) { 3317 dev_err(DEV, "Error while reading metadata, magic not found.\n"); 3318 rv = ERR_MD_INVALID; 3319 goto err; 3320 } 3321 if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) { 3322 dev_err(DEV, "unexpected al_offset: %d (expected %d)\n", 3323 be32_to_cpu(buffer->al_offset), bdev->md.al_offset); 3324 rv = ERR_MD_INVALID; 3325 goto err; 3326 } 3327 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) { 3328 dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n", 3329 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset); 3330 rv = ERR_MD_INVALID; 3331 goto err; 3332 } 3333 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) { 3334 dev_err(DEV, "unexpected md_size: %u (expected %u)\n", 3335 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect); 3336 rv = ERR_MD_INVALID; 3337 goto err; 3338 } 3339 3340 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) { 3341 dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n", 3342 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE); 3343 rv = ERR_MD_INVALID; 3344 goto err; 3345 } 3346 3347 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size); 3348 for (i = UI_CURRENT; i < UI_SIZE; i++) 3349 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]); 3350 bdev->md.flags = be32_to_cpu(buffer->flags); 3351 mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents); 3352 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid); 3353 3354 if (mdev->sync_conf.al_extents < 7) 3355 mdev->sync_conf.al_extents = 127; 3356 3357 err: 3358 mutex_unlock(&mdev->md_io_mutex); 3359 put_ldev(mdev); 3360 3361 return rv; 3362 } 3363 3364 /** 3365 * drbd_md_mark_dirty() - Mark meta data super block as dirty 3366 * @mdev: DRBD device. 3367 * 3368 * Call this function if you change anything that should be written to 3369 * the meta-data super block. This function sets MD_DIRTY, and starts a 3370 * timer that ensures that within five seconds you have to call drbd_md_sync(). 3371 */ 3372 void drbd_md_mark_dirty(struct drbd_conf *mdev) 3373 { 3374 set_bit(MD_DIRTY, &mdev->flags); 3375 mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ); 3376 } 3377 3378 3379 static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local) 3380 { 3381 int i; 3382 3383 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++) 3384 mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i]; 3385 } 3386 3387 void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local) 3388 { 3389 if (idx == UI_CURRENT) { 3390 if (mdev->state.role == R_PRIMARY) 3391 val |= 1; 3392 else 3393 val &= ~((u64)1); 3394 3395 drbd_set_ed_uuid(mdev, val); 3396 } 3397 3398 mdev->ldev->md.uuid[idx] = val; 3399 drbd_md_mark_dirty(mdev); 3400 } 3401 3402 3403 void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local) 3404 { 3405 if (mdev->ldev->md.uuid[idx]) { 3406 drbd_uuid_move_history(mdev); 3407 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx]; 3408 } 3409 _drbd_uuid_set(mdev, idx, val); 3410 } 3411 3412 /** 3413 * drbd_uuid_new_current() - Creates a new current UUID 3414 * @mdev: DRBD device. 3415 * 3416 * Creates a new current UUID, and rotates the old current UUID into 3417 * the bitmap slot. Causes an incremental resync upon next connect. 3418 */ 3419 void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local) 3420 { 3421 u64 val; 3422 3423 dev_info(DEV, "Creating new current UUID\n"); 3424 D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0); 3425 mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT]; 3426 3427 get_random_bytes(&val, sizeof(u64)); 3428 _drbd_uuid_set(mdev, UI_CURRENT, val); 3429 } 3430 3431 void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local) 3432 { 3433 if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0) 3434 return; 3435 3436 if (val == 0) { 3437 drbd_uuid_move_history(mdev); 3438 mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP]; 3439 mdev->ldev->md.uuid[UI_BITMAP] = 0; 3440 } else { 3441 if (mdev->ldev->md.uuid[UI_BITMAP]) 3442 dev_warn(DEV, "bm UUID already set"); 3443 3444 mdev->ldev->md.uuid[UI_BITMAP] = val; 3445 mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1); 3446 3447 } 3448 drbd_md_mark_dirty(mdev); 3449 } 3450 3451 /** 3452 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io() 3453 * @mdev: DRBD device. 3454 * 3455 * Sets all bits in the bitmap and writes the whole bitmap to stable storage. 3456 */ 3457 int drbd_bmio_set_n_write(struct drbd_conf *mdev) 3458 { 3459 int rv = -EIO; 3460 3461 if (get_ldev_if_state(mdev, D_ATTACHING)) { 3462 drbd_md_set_flag(mdev, MDF_FULL_SYNC); 3463 drbd_md_sync(mdev); 3464 drbd_bm_set_all(mdev); 3465 3466 rv = drbd_bm_write(mdev); 3467 3468 if (!rv) { 3469 drbd_md_clear_flag(mdev, MDF_FULL_SYNC); 3470 drbd_md_sync(mdev); 3471 } 3472 3473 put_ldev(mdev); 3474 } 3475 3476 return rv; 3477 } 3478 3479 /** 3480 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io() 3481 * @mdev: DRBD device. 3482 * 3483 * Clears all bits in the bitmap and writes the whole bitmap to stable storage. 3484 */ 3485 int drbd_bmio_clear_n_write(struct drbd_conf *mdev) 3486 { 3487 int rv = -EIO; 3488 3489 if (get_ldev_if_state(mdev, D_ATTACHING)) { 3490 drbd_bm_clear_all(mdev); 3491 rv = drbd_bm_write(mdev); 3492 put_ldev(mdev); 3493 } 3494 3495 return rv; 3496 } 3497 3498 static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused) 3499 { 3500 struct bm_io_work *work = container_of(w, struct bm_io_work, w); 3501 int rv; 3502 3503 D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0); 3504 3505 drbd_bm_lock(mdev, work->why); 3506 rv = work->io_fn(mdev); 3507 drbd_bm_unlock(mdev); 3508 3509 clear_bit(BITMAP_IO, &mdev->flags); 3510 wake_up(&mdev->misc_wait); 3511 3512 if (work->done) 3513 work->done(mdev, rv); 3514 3515 clear_bit(BITMAP_IO_QUEUED, &mdev->flags); 3516 work->why = NULL; 3517 3518 return 1; 3519 } 3520 3521 /** 3522 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap 3523 * @mdev: DRBD device. 3524 * @io_fn: IO callback to be called when bitmap IO is possible 3525 * @done: callback to be called after the bitmap IO was performed 3526 * @why: Descriptive text of the reason for doing the IO 3527 * 3528 * While IO on the bitmap happens we freeze application IO thus we ensure 3529 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be 3530 * called from worker context. It MUST NOT be used while a previous such 3531 * work is still pending! 3532 */ 3533 void drbd_queue_bitmap_io(struct drbd_conf *mdev, 3534 int (*io_fn)(struct drbd_conf *), 3535 void (*done)(struct drbd_conf *, int), 3536 char *why) 3537 { 3538 D_ASSERT(current == mdev->worker.task); 3539 3540 D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags)); 3541 D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags)); 3542 D_ASSERT(list_empty(&mdev->bm_io_work.w.list)); 3543 if (mdev->bm_io_work.why) 3544 dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n", 3545 why, mdev->bm_io_work.why); 3546 3547 mdev->bm_io_work.io_fn = io_fn; 3548 mdev->bm_io_work.done = done; 3549 mdev->bm_io_work.why = why; 3550 3551 set_bit(BITMAP_IO, &mdev->flags); 3552 if (atomic_read(&mdev->ap_bio_cnt) == 0) { 3553 if (list_empty(&mdev->bm_io_work.w.list)) { 3554 set_bit(BITMAP_IO_QUEUED, &mdev->flags); 3555 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w); 3556 } else 3557 dev_err(DEV, "FIXME avoided double queuing bm_io_work\n"); 3558 } 3559 } 3560 3561 /** 3562 * drbd_bitmap_io() - Does an IO operation on the whole bitmap 3563 * @mdev: DRBD device. 3564 * @io_fn: IO callback to be called when bitmap IO is possible 3565 * @why: Descriptive text of the reason for doing the IO 3566 * 3567 * freezes application IO while that the actual IO operations runs. This 3568 * functions MAY NOT be called from worker context. 3569 */ 3570 int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why) 3571 { 3572 int rv; 3573 3574 D_ASSERT(current != mdev->worker.task); 3575 3576 drbd_suspend_io(mdev); 3577 3578 drbd_bm_lock(mdev, why); 3579 rv = io_fn(mdev); 3580 drbd_bm_unlock(mdev); 3581 3582 drbd_resume_io(mdev); 3583 3584 return rv; 3585 } 3586 3587 void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local) 3588 { 3589 if ((mdev->ldev->md.flags & flag) != flag) { 3590 drbd_md_mark_dirty(mdev); 3591 mdev->ldev->md.flags |= flag; 3592 } 3593 } 3594 3595 void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local) 3596 { 3597 if ((mdev->ldev->md.flags & flag) != 0) { 3598 drbd_md_mark_dirty(mdev); 3599 mdev->ldev->md.flags &= ~flag; 3600 } 3601 } 3602 int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag) 3603 { 3604 return (bdev->md.flags & flag) != 0; 3605 } 3606 3607 static void md_sync_timer_fn(unsigned long data) 3608 { 3609 struct drbd_conf *mdev = (struct drbd_conf *) data; 3610 3611 drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work); 3612 } 3613 3614 static int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused) 3615 { 3616 dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n"); 3617 drbd_md_sync(mdev); 3618 3619 return 1; 3620 } 3621 3622 #ifdef CONFIG_DRBD_FAULT_INJECTION 3623 /* Fault insertion support including random number generator shamelessly 3624 * stolen from kernel/rcutorture.c */ 3625 struct fault_random_state { 3626 unsigned long state; 3627 unsigned long count; 3628 }; 3629 3630 #define FAULT_RANDOM_MULT 39916801 /* prime */ 3631 #define FAULT_RANDOM_ADD 479001701 /* prime */ 3632 #define FAULT_RANDOM_REFRESH 10000 3633 3634 /* 3635 * Crude but fast random-number generator. Uses a linear congruential 3636 * generator, with occasional help from get_random_bytes(). 3637 */ 3638 static unsigned long 3639 _drbd_fault_random(struct fault_random_state *rsp) 3640 { 3641 long refresh; 3642 3643 if (!rsp->count--) { 3644 get_random_bytes(&refresh, sizeof(refresh)); 3645 rsp->state += refresh; 3646 rsp->count = FAULT_RANDOM_REFRESH; 3647 } 3648 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD; 3649 return swahw32(rsp->state); 3650 } 3651 3652 static char * 3653 _drbd_fault_str(unsigned int type) { 3654 static char *_faults[] = { 3655 [DRBD_FAULT_MD_WR] = "Meta-data write", 3656 [DRBD_FAULT_MD_RD] = "Meta-data read", 3657 [DRBD_FAULT_RS_WR] = "Resync write", 3658 [DRBD_FAULT_RS_RD] = "Resync read", 3659 [DRBD_FAULT_DT_WR] = "Data write", 3660 [DRBD_FAULT_DT_RD] = "Data read", 3661 [DRBD_FAULT_DT_RA] = "Data read ahead", 3662 [DRBD_FAULT_BM_ALLOC] = "BM allocation", 3663 [DRBD_FAULT_AL_EE] = "EE allocation" 3664 }; 3665 3666 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**"; 3667 } 3668 3669 unsigned int 3670 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) 3671 { 3672 static struct fault_random_state rrs = {0, 0}; 3673 3674 unsigned int ret = ( 3675 (fault_devs == 0 || 3676 ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) && 3677 (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate)); 3678 3679 if (ret) { 3680 fault_count++; 3681 3682 if (printk_ratelimit()) 3683 dev_warn(DEV, "***Simulating %s failure\n", 3684 _drbd_fault_str(type)); 3685 } 3686 3687 return ret; 3688 } 3689 #endif 3690 3691 const char *drbd_buildtag(void) 3692 { 3693 /* DRBD built from external sources has here a reference to the 3694 git hash of the source code. */ 3695 3696 static char buildtag[38] = "\0uilt-in"; 3697 3698 if (buildtag[0] == 0) { 3699 #ifdef CONFIG_MODULES 3700 if (THIS_MODULE != NULL) 3701 sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion); 3702 else 3703 #endif 3704 buildtag[0] = 'b'; 3705 } 3706 3707 return buildtag; 3708 } 3709 3710 module_init(drbd_init) 3711 module_exit(drbd_cleanup) 3712 3713 EXPORT_SYMBOL(drbd_conn_str); 3714 EXPORT_SYMBOL(drbd_role_str); 3715 EXPORT_SYMBOL(drbd_disk_str); 3716 EXPORT_SYMBOL(drbd_set_st_err_str); 3717