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drbd_main.c
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linux-6.19.14/drivers/block/drbd/drbd_main.c
1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 drbd.c 4 5 This file is part of DRBD by Philipp Reisner and Lars Ellenberg. 6 7 Copyright (C) 2001-2008, LINBIT Information Technologies GmbH. 8 Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>. 9 Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>. 10 11 Thanks to Carter Burden, Bart Grantham and Gennadiy Nerubayev 12 from Logicworks, Inc. for making SDP replication support possible. 13 14 15 */ 16 17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 18 19#include <linux/module.h> 20#include <linux/jiffies.h> 21#include <linux/drbd.h> 22#include <linux/uaccess.h> 23#include <asm/types.h> 24#include <net/sock.h> 25#include <linux/ctype.h> 26#include <linux/mutex.h> 27#include <linux/fs.h> 28#include <linux/file.h> 29#include <linux/proc_fs.h> 30#include <linux/init.h> 31#include <linux/mm.h> 32#include <linux/memcontrol.h> 33#include <linux/mm_inline.h> 34#include <linux/slab.h> 35#include <linux/random.h> 36#include <linux/reboot.h> 37#include <linux/notifier.h> 38#include <linux/kthread.h> 39#include <linux/workqueue.h> 40#include <linux/unistd.h> 41#include <linux/vmalloc.h> 42#include <linux/sched/signal.h> 43 44#include <linux/drbd_limits.h> 45#include "drbd_int.h" 46#include "drbd_protocol.h" 47#include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */ 48#include "drbd_vli.h" 49#include "drbd_debugfs.h" 50 51static DEFINE_MUTEX(drbd_main_mutex); 52static int drbd_open(struct gendisk *disk, blk_mode_t mode); 53static void drbd_release(struct gendisk *gd); 54static void md_sync_timer_fn(struct timer_list *t); 55static int w_bitmap_io(struct drbd_work *w, int unused); 56 57MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, " 58 "Lars Ellenberg <lars@linbit.com>"); 59MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION); 60MODULE_VERSION(REL_VERSION); 61MODULE_LICENSE("GPL"); 62MODULE_PARM_DESC(minor_count, "Approximate number of drbd devices (" 63 __stringify(DRBD_MINOR_COUNT_MIN) "-" __stringify(DRBD_MINOR_COUNT_MAX) ")"); 64MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR); 65 66#include <linux/moduleparam.h> 67/* thanks to these macros, if compiled into the kernel (not-module), 68 * these become boot parameters (e.g., drbd.minor_count) */ 69 70#ifdef CONFIG_DRBD_FAULT_INJECTION 71int drbd_enable_faults; 72int drbd_fault_rate; 73static int drbd_fault_count; 74static int drbd_fault_devs; 75/* bitmap of enabled faults */ 76module_param_named(enable_faults, drbd_enable_faults, int, 0664); 77/* fault rate % value - applies to all enabled faults */ 78module_param_named(fault_rate, drbd_fault_rate, int, 0664); 79/* count of faults inserted */ 80module_param_named(fault_count, drbd_fault_count, int, 0664); 81/* bitmap of devices to insert faults on */ 82module_param_named(fault_devs, drbd_fault_devs, int, 0644); 83#endif 84 85/* module parameters we can keep static */ 86static bool drbd_allow_oos; /* allow_open_on_secondary */ 87static bool drbd_disable_sendpage; 88MODULE_PARM_DESC(allow_oos, "DONT USE!"); 89module_param_named(allow_oos, drbd_allow_oos, bool, 0); 90module_param_named(disable_sendpage, drbd_disable_sendpage, bool, 0644); 91 92/* module parameters we share */ 93int drbd_proc_details; /* Detail level in proc drbd*/ 94module_param_named(proc_details, drbd_proc_details, int, 0644); 95/* module parameters shared with defaults */ 96unsigned int drbd_minor_count = DRBD_MINOR_COUNT_DEF; 97/* Module parameter for setting the user mode helper program 98 * to run. Default is /sbin/drbdadm */ 99char drbd_usermode_helper[80] = "/sbin/drbdadm"; 100module_param_named(minor_count, drbd_minor_count, uint, 0444); 101module_param_string(usermode_helper, drbd_usermode_helper, sizeof(drbd_usermode_helper), 0644); 102 103/* in 2.6.x, our device mapping and config info contains our virtual gendisks 104 * as member "struct gendisk *vdisk;" 105 */ 106struct idr drbd_devices; 107struct list_head drbd_resources; 108struct mutex resources_mutex; 109 110struct kmem_cache *drbd_request_cache; 111struct kmem_cache *drbd_ee_cache; /* peer requests */ 112struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 113struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 114mempool_t drbd_request_mempool; 115mempool_t drbd_ee_mempool; 116mempool_t drbd_md_io_page_pool; 117mempool_t drbd_buffer_page_pool; 118struct bio_set drbd_md_io_bio_set; 119struct bio_set drbd_io_bio_set; 120 121DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5); 122 123static const struct block_device_operations drbd_ops = { 124 .owner = THIS_MODULE, 125 .submit_bio = drbd_submit_bio, 126 .open = drbd_open, 127 .release = drbd_release, 128}; 129 130#ifdef __CHECKER__ 131/* When checking with sparse, and this is an inline function, sparse will 132 give tons of false positives. When this is a real functions sparse works. 133 */ 134int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins) 135{ 136 int io_allowed; 137 138 atomic_inc(&device->local_cnt); 139 io_allowed = (device->state.disk >= mins); 140 if (!io_allowed) { 141 if (atomic_dec_and_test(&device->local_cnt)) 142 wake_up(&device->misc_wait); 143 } 144 return io_allowed; 145} 146 147#endif 148 149/** 150 * tl_release() - mark as BARRIER_ACKED all requests in the corresponding transfer log epoch 151 * @connection: DRBD connection. 152 * @barrier_nr: Expected identifier of the DRBD write barrier packet. 153 * @set_size: Expected number of requests before that barrier. 154 * 155 * In case the passed barrier_nr or set_size does not match the oldest 156 * epoch of not yet barrier-acked requests, this function will cause a 157 * termination of the connection. 158 */ 159void tl_release(struct drbd_connection *connection, unsigned int barrier_nr, 160 unsigned int set_size) 161{ 162 struct drbd_request *r; 163 struct drbd_request *req = NULL, *tmp = NULL; 164 int expect_epoch = 0; 165 int expect_size = 0; 166 167 spin_lock_irq(&connection->resource->req_lock); 168 169 /* find oldest not yet barrier-acked write request, 170 * count writes in its epoch. */ 171 list_for_each_entry(r, &connection->transfer_log, tl_requests) { 172 const unsigned s = r->rq_state; 173 if (!req) { 174 if (!(s & RQ_WRITE)) 175 continue; 176 if (!(s & RQ_NET_MASK)) 177 continue; 178 if (s & RQ_NET_DONE) 179 continue; 180 req = r; 181 expect_epoch = req->epoch; 182 expect_size ++; 183 } else { 184 if (r->epoch != expect_epoch) 185 break; 186 if (!(s & RQ_WRITE)) 187 continue; 188 /* if (s & RQ_DONE): not expected */ 189 /* if (!(s & RQ_NET_MASK)): not expected */ 190 expect_size++; 191 } 192 } 193 194 /* first some paranoia code */ 195 if (req == NULL) { 196 drbd_err(connection, "BAD! BarrierAck #%u received, but no epoch in tl!?\n", 197 barrier_nr); 198 goto bail; 199 } 200 if (expect_epoch != barrier_nr) { 201 drbd_err(connection, "BAD! BarrierAck #%u received, expected #%u!\n", 202 barrier_nr, expect_epoch); 203 goto bail; 204 } 205 206 if (expect_size != set_size) { 207 drbd_err(connection, "BAD! BarrierAck #%u received with n_writes=%u, expected n_writes=%u!\n", 208 barrier_nr, set_size, expect_size); 209 goto bail; 210 } 211 212 /* Clean up list of requests processed during current epoch. */ 213 /* this extra list walk restart is paranoia, 214 * to catch requests being barrier-acked "unexpectedly". 215 * It usually should find the same req again, or some READ preceding it. */ 216 list_for_each_entry(req, &connection->transfer_log, tl_requests) 217 if (req->epoch == expect_epoch) { 218 tmp = req; 219 break; 220 } 221 req = list_prepare_entry(tmp, &connection->transfer_log, tl_requests); 222 list_for_each_entry_safe_from(req, r, &connection->transfer_log, tl_requests) { 223 struct drbd_peer_device *peer_device; 224 if (req->epoch != expect_epoch) 225 break; 226 peer_device = conn_peer_device(connection, req->device->vnr); 227 _req_mod(req, BARRIER_ACKED, peer_device); 228 } 229 spin_unlock_irq(&connection->resource->req_lock); 230 231 return; 232 233bail: 234 spin_unlock_irq(&connection->resource->req_lock); 235 conn_request_state(connection, NS(conn, C_PROTOCOL_ERROR), CS_HARD); 236} 237 238 239/** 240 * _tl_restart() - Walks the transfer log, and applies an action to all requests 241 * @connection: DRBD connection to operate on. 242 * @what: The action/event to perform with all request objects 243 * 244 * @what might be one of CONNECTION_LOST_WHILE_PENDING, RESEND, FAIL_FROZEN_DISK_IO, 245 * RESTART_FROZEN_DISK_IO. 246 */ 247/* must hold resource->req_lock */ 248void _tl_restart(struct drbd_connection *connection, enum drbd_req_event what) 249{ 250 struct drbd_peer_device *peer_device; 251 struct drbd_request *req, *r; 252 253 list_for_each_entry_safe(req, r, &connection->transfer_log, tl_requests) { 254 peer_device = conn_peer_device(connection, req->device->vnr); 255 _req_mod(req, what, peer_device); 256 } 257} 258 259void tl_restart(struct drbd_connection *connection, enum drbd_req_event what) 260{ 261 spin_lock_irq(&connection->resource->req_lock); 262 _tl_restart(connection, what); 263 spin_unlock_irq(&connection->resource->req_lock); 264} 265 266/** 267 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL 268 * @connection: DRBD connection. 269 * 270 * This is called after the connection to the peer was lost. The storage covered 271 * by the requests on the transfer gets marked as our of sync. Called from the 272 * receiver thread and the worker thread. 273 */ 274void tl_clear(struct drbd_connection *connection) 275{ 276 tl_restart(connection, CONNECTION_LOST_WHILE_PENDING); 277} 278 279/** 280 * tl_abort_disk_io() - Abort disk I/O for all requests for a certain device in the TL 281 * @device: DRBD device. 282 */ 283void tl_abort_disk_io(struct drbd_device *device) 284{ 285 struct drbd_connection *connection = first_peer_device(device)->connection; 286 struct drbd_request *req, *r; 287 288 spin_lock_irq(&connection->resource->req_lock); 289 list_for_each_entry_safe(req, r, &connection->transfer_log, tl_requests) { 290 if (!(req->rq_state & RQ_LOCAL_PENDING)) 291 continue; 292 if (req->device != device) 293 continue; 294 _req_mod(req, ABORT_DISK_IO, NULL); 295 } 296 spin_unlock_irq(&connection->resource->req_lock); 297} 298 299static int drbd_thread_setup(void *arg) 300{ 301 struct drbd_thread *thi = (struct drbd_thread *) arg; 302 struct drbd_resource *resource = thi->resource; 303 unsigned long flags; 304 int retval; 305 306 snprintf(current->comm, sizeof(current->comm), "drbd_%c_%s", 307 thi->name[0], 308 resource->name); 309 310 allow_kernel_signal(DRBD_SIGKILL); 311 allow_kernel_signal(SIGXCPU); 312restart: 313 retval = thi->function(thi); 314 315 spin_lock_irqsave(&thi->t_lock, flags); 316 317 /* if the receiver has been "EXITING", the last thing it did 318 * was set the conn state to "StandAlone", 319 * if now a re-connect request comes in, conn state goes C_UNCONNECTED, 320 * and receiver thread will be "started". 321 * drbd_thread_start needs to set "RESTARTING" in that case. 322 * t_state check and assignment needs to be within the same spinlock, 323 * so either thread_start sees EXITING, and can remap to RESTARTING, 324 * or thread_start see NONE, and can proceed as normal. 325 */ 326 327 if (thi->t_state == RESTARTING) { 328 drbd_info(resource, "Restarting %s thread\n", thi->name); 329 thi->t_state = RUNNING; 330 spin_unlock_irqrestore(&thi->t_lock, flags); 331 goto restart; 332 } 333 334 thi->task = NULL; 335 thi->t_state = NONE; 336 smp_mb(); 337 complete_all(&thi->stop); 338 spin_unlock_irqrestore(&thi->t_lock, flags); 339 340 drbd_info(resource, "Terminating %s\n", current->comm); 341 342 /* Release mod reference taken when thread was started */ 343 344 if (thi->connection) 345 kref_put(&thi->connection->kref, drbd_destroy_connection); 346 kref_put(&resource->kref, drbd_destroy_resource); 347 module_put(THIS_MODULE); 348 return retval; 349} 350 351static void drbd_thread_init(struct drbd_resource *resource, struct drbd_thread *thi, 352 int (*func) (struct drbd_thread *), const char *name) 353{ 354 spin_lock_init(&thi->t_lock); 355 thi->task = NULL; 356 thi->t_state = NONE; 357 thi->function = func; 358 thi->resource = resource; 359 thi->connection = NULL; 360 thi->name = name; 361} 362 363int drbd_thread_start(struct drbd_thread *thi) 364{ 365 struct drbd_resource *resource = thi->resource; 366 struct task_struct *nt; 367 unsigned long flags; 368 369 /* is used from state engine doing drbd_thread_stop_nowait, 370 * while holding the req lock irqsave */ 371 spin_lock_irqsave(&thi->t_lock, flags); 372 373 switch (thi->t_state) { 374 case NONE: 375 drbd_info(resource, "Starting %s thread (from %s [%d])\n", 376 thi->name, current->comm, current->pid); 377 378 /* Get ref on module for thread - this is released when thread exits */ 379 if (!try_module_get(THIS_MODULE)) { 380 drbd_err(resource, "Failed to get module reference in drbd_thread_start\n"); 381 spin_unlock_irqrestore(&thi->t_lock, flags); 382 return false; 383 } 384 385 kref_get(&resource->kref); 386 if (thi->connection) 387 kref_get(&thi->connection->kref); 388 389 init_completion(&thi->stop); 390 thi->reset_cpu_mask = 1; 391 thi->t_state = RUNNING; 392 spin_unlock_irqrestore(&thi->t_lock, flags); 393 flush_signals(current); /* otherw. may get -ERESTARTNOINTR */ 394 395 nt = kthread_create(drbd_thread_setup, (void *) thi, 396 "drbd_%c_%s", thi->name[0], thi->resource->name); 397 398 if (IS_ERR(nt)) { 399 drbd_err(resource, "Couldn't start thread\n"); 400 401 if (thi->connection) 402 kref_put(&thi->connection->kref, drbd_destroy_connection); 403 kref_put(&resource->kref, drbd_destroy_resource); 404 module_put(THIS_MODULE); 405 return false; 406 } 407 spin_lock_irqsave(&thi->t_lock, flags); 408 thi->task = nt; 409 thi->t_state = RUNNING; 410 spin_unlock_irqrestore(&thi->t_lock, flags); 411 wake_up_process(nt); 412 break; 413 case EXITING: 414 thi->t_state = RESTARTING; 415 drbd_info(resource, "Restarting %s thread (from %s [%d])\n", 416 thi->name, current->comm, current->pid); 417 fallthrough; 418 case RUNNING: 419 case RESTARTING: 420 default: 421 spin_unlock_irqrestore(&thi->t_lock, flags); 422 break; 423 } 424 425 return true; 426} 427 428 429void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait) 430{ 431 unsigned long flags; 432 433 enum drbd_thread_state ns = restart ? RESTARTING : EXITING; 434 435 /* may be called from state engine, holding the req lock irqsave */ 436 spin_lock_irqsave(&thi->t_lock, flags); 437 438 if (thi->t_state == NONE) { 439 spin_unlock_irqrestore(&thi->t_lock, flags); 440 if (restart) 441 drbd_thread_start(thi); 442 return; 443 } 444 445 if (thi->t_state != ns) { 446 if (thi->task == NULL) { 447 spin_unlock_irqrestore(&thi->t_lock, flags); 448 return; 449 } 450 451 thi->t_state = ns; 452 smp_mb(); 453 init_completion(&thi->stop); 454 if (thi->task != current) 455 send_sig(DRBD_SIGKILL, thi->task, 1); 456 } 457 458 spin_unlock_irqrestore(&thi->t_lock, flags); 459 460 if (wait) 461 wait_for_completion(&thi->stop); 462} 463 464#ifdef CONFIG_SMP 465/* 466 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs 467 * 468 * Forces all threads of a resource onto the same CPU. This is beneficial for 469 * DRBD's performance. May be overwritten by user's configuration. 470 */ 471static void drbd_calc_cpu_mask(cpumask_var_t *cpu_mask) 472{ 473 unsigned int *resources_per_cpu, min_index = ~0; 474 475 resources_per_cpu = kcalloc(nr_cpu_ids, sizeof(*resources_per_cpu), 476 GFP_KERNEL); 477 if (resources_per_cpu) { 478 struct drbd_resource *resource; 479 unsigned int cpu, min = ~0; 480 481 rcu_read_lock(); 482 for_each_resource_rcu(resource, &drbd_resources) { 483 for_each_cpu(cpu, resource->cpu_mask) 484 resources_per_cpu[cpu]++; 485 } 486 rcu_read_unlock(); 487 for_each_online_cpu(cpu) { 488 if (resources_per_cpu[cpu] < min) { 489 min = resources_per_cpu[cpu]; 490 min_index = cpu; 491 } 492 } 493 kfree(resources_per_cpu); 494 } 495 if (min_index == ~0) { 496 cpumask_setall(*cpu_mask); 497 return; 498 } 499 cpumask_set_cpu(min_index, *cpu_mask); 500} 501 502/** 503 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread 504 * @thi: drbd_thread object 505 * 506 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die 507 * prematurely. 508 */ 509void drbd_thread_current_set_cpu(struct drbd_thread *thi) 510{ 511 struct drbd_resource *resource = thi->resource; 512 struct task_struct *p = current; 513 514 if (!thi->reset_cpu_mask) 515 return; 516 thi->reset_cpu_mask = 0; 517 set_cpus_allowed_ptr(p, resource->cpu_mask); 518} 519#else 520#define drbd_calc_cpu_mask(A) ({}) 521#endif 522 523/* 524 * drbd_header_size - size of a packet header 525 * 526 * The header size is a multiple of 8, so any payload following the header is 527 * word aligned on 64-bit architectures. (The bitmap send and receive code 528 * relies on this.) 529 */ 530unsigned int drbd_header_size(struct drbd_connection *connection) 531{ 532 if (connection->agreed_pro_version >= 100) { 533 BUILD_BUG_ON(!IS_ALIGNED(sizeof(struct p_header100), 8)); 534 return sizeof(struct p_header100); 535 } else { 536 BUILD_BUG_ON(sizeof(struct p_header80) != 537 sizeof(struct p_header95)); 538 BUILD_BUG_ON(!IS_ALIGNED(sizeof(struct p_header80), 8)); 539 return sizeof(struct p_header80); 540 } 541} 542 543static unsigned int prepare_header80(struct p_header80 *h, enum drbd_packet cmd, int size) 544{ 545 h->magic = cpu_to_be32(DRBD_MAGIC); 546 h->command = cpu_to_be16(cmd); 547 h->length = cpu_to_be16(size); 548 return sizeof(struct p_header80); 549} 550 551static unsigned int prepare_header95(struct p_header95 *h, enum drbd_packet cmd, int size) 552{ 553 h->magic = cpu_to_be16(DRBD_MAGIC_BIG); 554 h->command = cpu_to_be16(cmd); 555 h->length = cpu_to_be32(size); 556 return sizeof(struct p_header95); 557} 558 559static unsigned int prepare_header100(struct p_header100 *h, enum drbd_packet cmd, 560 int size, int vnr) 561{ 562 h->magic = cpu_to_be32(DRBD_MAGIC_100); 563 h->volume = cpu_to_be16(vnr); 564 h->command = cpu_to_be16(cmd); 565 h->length = cpu_to_be32(size); 566 h->pad = 0; 567 return sizeof(struct p_header100); 568} 569 570static unsigned int prepare_header(struct drbd_connection *connection, int vnr, 571 void *buffer, enum drbd_packet cmd, int size) 572{ 573 if (connection->agreed_pro_version >= 100) 574 return prepare_header100(buffer, cmd, size, vnr); 575 else if (connection->agreed_pro_version >= 95 && 576 size > DRBD_MAX_SIZE_H80_PACKET) 577 return prepare_header95(buffer, cmd, size); 578 else 579 return prepare_header80(buffer, cmd, size); 580} 581 582static void *__conn_prepare_command(struct drbd_connection *connection, 583 struct drbd_socket *sock) 584{ 585 if (!sock->socket) 586 return NULL; 587 return sock->sbuf + drbd_header_size(connection); 588} 589 590void *conn_prepare_command(struct drbd_connection *connection, struct drbd_socket *sock) 591{ 592 void *p; 593 594 mutex_lock(&sock->mutex); 595 p = __conn_prepare_command(connection, sock); 596 if (!p) 597 mutex_unlock(&sock->mutex); 598 599 return p; 600} 601 602void *drbd_prepare_command(struct drbd_peer_device *peer_device, struct drbd_socket *sock) 603{ 604 return conn_prepare_command(peer_device->connection, sock); 605} 606 607static int __send_command(struct drbd_connection *connection, int vnr, 608 struct drbd_socket *sock, enum drbd_packet cmd, 609 unsigned int header_size, void *data, 610 unsigned int size) 611{ 612 int msg_flags; 613 int err; 614 615 /* 616 * Called with @data == NULL and the size of the data blocks in @size 617 * for commands that send data blocks. For those commands, omit the 618 * MSG_MORE flag: this will increase the likelihood that data blocks 619 * which are page aligned on the sender will end up page aligned on the 620 * receiver. 621 */ 622 msg_flags = data ? MSG_MORE : 0; 623 624 header_size += prepare_header(connection, vnr, sock->sbuf, cmd, 625 header_size + size); 626 err = drbd_send_all(connection, sock->socket, sock->sbuf, header_size, 627 msg_flags); 628 if (data && !err) 629 err = drbd_send_all(connection, sock->socket, data, size, 0); 630 /* DRBD protocol "pings" are latency critical. 631 * This is supposed to trigger tcp_push_pending_frames() */ 632 if (!err && (cmd == P_PING || cmd == P_PING_ACK)) 633 tcp_sock_set_nodelay(sock->socket->sk); 634 635 return err; 636} 637 638static int __conn_send_command(struct drbd_connection *connection, struct drbd_socket *sock, 639 enum drbd_packet cmd, unsigned int header_size, 640 void *data, unsigned int size) 641{ 642 return __send_command(connection, 0, sock, cmd, header_size, data, size); 643} 644 645int conn_send_command(struct drbd_connection *connection, struct drbd_socket *sock, 646 enum drbd_packet cmd, unsigned int header_size, 647 void *data, unsigned int size) 648{ 649 int err; 650 651 err = __conn_send_command(connection, sock, cmd, header_size, data, size); 652 mutex_unlock(&sock->mutex); 653 return err; 654} 655 656int drbd_send_command(struct drbd_peer_device *peer_device, struct drbd_socket *sock, 657 enum drbd_packet cmd, unsigned int header_size, 658 void *data, unsigned int size) 659{ 660 int err; 661 662 err = __send_command(peer_device->connection, peer_device->device->vnr, 663 sock, cmd, header_size, data, size); 664 mutex_unlock(&sock->mutex); 665 return err; 666} 667 668int drbd_send_ping(struct drbd_connection *connection) 669{ 670 struct drbd_socket *sock; 671 672 sock = &connection->meta; 673 if (!conn_prepare_command(connection, sock)) 674 return -EIO; 675 return conn_send_command(connection, sock, P_PING, 0, NULL, 0); 676} 677 678int drbd_send_ping_ack(struct drbd_connection *connection) 679{ 680 struct drbd_socket *sock; 681 682 sock = &connection->meta; 683 if (!conn_prepare_command(connection, sock)) 684 return -EIO; 685 return conn_send_command(connection, sock, P_PING_ACK, 0, NULL, 0); 686} 687 688int drbd_send_sync_param(struct drbd_peer_device *peer_device) 689{ 690 struct drbd_socket *sock; 691 struct p_rs_param_95 *p; 692 int size; 693 const int apv = peer_device->connection->agreed_pro_version; 694 enum drbd_packet cmd; 695 struct net_conf *nc; 696 struct disk_conf *dc; 697 698 sock = &peer_device->connection->data; 699 p = drbd_prepare_command(peer_device, sock); 700 if (!p) 701 return -EIO; 702 703 rcu_read_lock(); 704 nc = rcu_dereference(peer_device->connection->net_conf); 705 706 size = apv <= 87 ? sizeof(struct p_rs_param) 707 : apv == 88 ? sizeof(struct p_rs_param) 708 + strlen(nc->verify_alg) + 1 709 : apv <= 94 ? sizeof(struct p_rs_param_89) 710 : /* apv >= 95 */ sizeof(struct p_rs_param_95); 711 712 cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM; 713 714 /* initialize verify_alg and csums_alg */ 715 BUILD_BUG_ON(sizeof(p->algs) != 2 * SHARED_SECRET_MAX); 716 memset(&p->algs, 0, sizeof(p->algs)); 717 718 if (get_ldev(peer_device->device)) { 719 dc = rcu_dereference(peer_device->device->ldev->disk_conf); 720 p->resync_rate = cpu_to_be32(dc->resync_rate); 721 p->c_plan_ahead = cpu_to_be32(dc->c_plan_ahead); 722 p->c_delay_target = cpu_to_be32(dc->c_delay_target); 723 p->c_fill_target = cpu_to_be32(dc->c_fill_target); 724 p->c_max_rate = cpu_to_be32(dc->c_max_rate); 725 put_ldev(peer_device->device); 726 } else { 727 p->resync_rate = cpu_to_be32(DRBD_RESYNC_RATE_DEF); 728 p->c_plan_ahead = cpu_to_be32(DRBD_C_PLAN_AHEAD_DEF); 729 p->c_delay_target = cpu_to_be32(DRBD_C_DELAY_TARGET_DEF); 730 p->c_fill_target = cpu_to_be32(DRBD_C_FILL_TARGET_DEF); 731 p->c_max_rate = cpu_to_be32(DRBD_C_MAX_RATE_DEF); 732 } 733 734 if (apv >= 88) 735 strcpy(p->verify_alg, nc->verify_alg); 736 if (apv >= 89) 737 strcpy(p->csums_alg, nc->csums_alg); 738 rcu_read_unlock(); 739 740 return drbd_send_command(peer_device, sock, cmd, size, NULL, 0); 741} 742 743int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cmd) 744{ 745 struct drbd_socket *sock; 746 struct p_protocol *p; 747 struct net_conf *nc; 748 int size, cf; 749 750 sock = &connection->data; 751 p = __conn_prepare_command(connection, sock); 752 if (!p) 753 return -EIO; 754 755 rcu_read_lock(); 756 nc = rcu_dereference(connection->net_conf); 757 758 if (nc->tentative && connection->agreed_pro_version < 92) { 759 rcu_read_unlock(); 760 drbd_err(connection, "--dry-run is not supported by peer"); 761 return -EOPNOTSUPP; 762 } 763 764 size = sizeof(*p); 765 if (connection->agreed_pro_version >= 87) 766 size += strlen(nc->integrity_alg) + 1; 767 768 p->protocol = cpu_to_be32(nc->wire_protocol); 769 p->after_sb_0p = cpu_to_be32(nc->after_sb_0p); 770 p->after_sb_1p = cpu_to_be32(nc->after_sb_1p); 771 p->after_sb_2p = cpu_to_be32(nc->after_sb_2p); 772 p->two_primaries = cpu_to_be32(nc->two_primaries); 773 cf = 0; 774 if (nc->discard_my_data) 775 cf |= CF_DISCARD_MY_DATA; 776 if (nc->tentative) 777 cf |= CF_DRY_RUN; 778 p->conn_flags = cpu_to_be32(cf); 779 780 if (connection->agreed_pro_version >= 87) 781 strcpy(p->integrity_alg, nc->integrity_alg); 782 rcu_read_unlock(); 783 784 return __conn_send_command(connection, sock, cmd, size, NULL, 0); 785} 786 787int drbd_send_protocol(struct drbd_connection *connection) 788{ 789 int err; 790 791 mutex_lock(&connection->data.mutex); 792 err = __drbd_send_protocol(connection, P_PROTOCOL); 793 mutex_unlock(&connection->data.mutex); 794 795 return err; 796} 797 798static int _drbd_send_uuids(struct drbd_peer_device *peer_device, u64 uuid_flags) 799{ 800 struct drbd_device *device = peer_device->device; 801 struct drbd_socket *sock; 802 struct p_uuids *p; 803 int i; 804 805 if (!get_ldev_if_state(device, D_NEGOTIATING)) 806 return 0; 807 808 sock = &peer_device->connection->data; 809 p = drbd_prepare_command(peer_device, sock); 810 if (!p) { 811 put_ldev(device); 812 return -EIO; 813 } 814 spin_lock_irq(&device->ldev->md.uuid_lock); 815 for (i = UI_CURRENT; i < UI_SIZE; i++) 816 p->uuid[i] = cpu_to_be64(device->ldev->md.uuid[i]); 817 spin_unlock_irq(&device->ldev->md.uuid_lock); 818 819 device->comm_bm_set = drbd_bm_total_weight(device); 820 p->uuid[UI_SIZE] = cpu_to_be64(device->comm_bm_set); 821 rcu_read_lock(); 822 uuid_flags |= rcu_dereference(peer_device->connection->net_conf)->discard_my_data ? 1 : 0; 823 rcu_read_unlock(); 824 uuid_flags |= test_bit(CRASHED_PRIMARY, &device->flags) ? 2 : 0; 825 uuid_flags |= device->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0; 826 p->uuid[UI_FLAGS] = cpu_to_be64(uuid_flags); 827 828 put_ldev(device); 829 return drbd_send_command(peer_device, sock, P_UUIDS, sizeof(*p), NULL, 0); 830} 831 832int drbd_send_uuids(struct drbd_peer_device *peer_device) 833{ 834 return _drbd_send_uuids(peer_device, 0); 835} 836 837int drbd_send_uuids_skip_initial_sync(struct drbd_peer_device *peer_device) 838{ 839 return _drbd_send_uuids(peer_device, 8); 840} 841 842void drbd_print_uuids(struct drbd_device *device, const char *text) 843{ 844 if (get_ldev_if_state(device, D_NEGOTIATING)) { 845 u64 *uuid = device->ldev->md.uuid; 846 drbd_info(device, "%s %016llX:%016llX:%016llX:%016llX\n", 847 text, 848 (unsigned long long)uuid[UI_CURRENT], 849 (unsigned long long)uuid[UI_BITMAP], 850 (unsigned long long)uuid[UI_HISTORY_START], 851 (unsigned long long)uuid[UI_HISTORY_END]); 852 put_ldev(device); 853 } else { 854 drbd_info(device, "%s effective data uuid: %016llX\n", 855 text, 856 (unsigned long long)device->ed_uuid); 857 } 858} 859 860void drbd_gen_and_send_sync_uuid(struct drbd_peer_device *peer_device) 861{ 862 struct drbd_device *device = peer_device->device; 863 struct drbd_socket *sock; 864 struct p_rs_uuid *p; 865 u64 uuid; 866 867 D_ASSERT(device, device->state.disk == D_UP_TO_DATE); 868 869 uuid = device->ldev->md.uuid[UI_BITMAP]; 870 if (uuid && uuid != UUID_JUST_CREATED) 871 uuid = uuid + UUID_NEW_BM_OFFSET; 872 else 873 get_random_bytes(&uuid, sizeof(u64)); 874 drbd_uuid_set(device, UI_BITMAP, uuid); 875 drbd_print_uuids(device, "updated sync UUID"); 876 drbd_md_sync(device); 877 878 sock = &peer_device->connection->data; 879 p = drbd_prepare_command(peer_device, sock); 880 if (p) { 881 p->uuid = cpu_to_be64(uuid); 882 drbd_send_command(peer_device, sock, P_SYNC_UUID, sizeof(*p), NULL, 0); 883 } 884} 885 886int drbd_send_sizes(struct drbd_peer_device *peer_device, int trigger_reply, enum dds_flags flags) 887{ 888 struct drbd_device *device = peer_device->device; 889 struct drbd_socket *sock; 890 struct p_sizes *p; 891 sector_t d_size, u_size; 892 int q_order_type; 893 unsigned int max_bio_size; 894 unsigned int packet_size; 895 896 sock = &peer_device->connection->data; 897 p = drbd_prepare_command(peer_device, sock); 898 if (!p) 899 return -EIO; 900 901 packet_size = sizeof(*p); 902 if (peer_device->connection->agreed_features & DRBD_FF_WSAME) 903 packet_size += sizeof(p->qlim[0]); 904 905 memset(p, 0, packet_size); 906 if (get_ldev_if_state(device, D_NEGOTIATING)) { 907 struct block_device *bdev = device->ldev->backing_bdev; 908 struct request_queue *q = bdev_get_queue(bdev); 909 910 d_size = drbd_get_max_capacity(device->ldev); 911 rcu_read_lock(); 912 u_size = rcu_dereference(device->ldev->disk_conf)->disk_size; 913 rcu_read_unlock(); 914 q_order_type = drbd_queue_order_type(device); 915 max_bio_size = queue_max_hw_sectors(q) << 9; 916 max_bio_size = min(max_bio_size, DRBD_MAX_BIO_SIZE); 917 p->qlim->physical_block_size = 918 cpu_to_be32(bdev_physical_block_size(bdev)); 919 p->qlim->logical_block_size = 920 cpu_to_be32(bdev_logical_block_size(bdev)); 921 p->qlim->alignment_offset = 922 cpu_to_be32(bdev_alignment_offset(bdev)); 923 p->qlim->io_min = cpu_to_be32(bdev_io_min(bdev)); 924 p->qlim->io_opt = cpu_to_be32(bdev_io_opt(bdev)); 925 p->qlim->discard_enabled = !!bdev_max_discard_sectors(bdev); 926 put_ldev(device); 927 } else { 928 struct request_queue *q = device->rq_queue; 929 930 p->qlim->physical_block_size = 931 cpu_to_be32(queue_physical_block_size(q)); 932 p->qlim->logical_block_size = 933 cpu_to_be32(queue_logical_block_size(q)); 934 p->qlim->alignment_offset = 0; 935 p->qlim->io_min = cpu_to_be32(queue_io_min(q)); 936 p->qlim->io_opt = cpu_to_be32(queue_io_opt(q)); 937 p->qlim->discard_enabled = 0; 938 939 d_size = 0; 940 u_size = 0; 941 q_order_type = QUEUE_ORDERED_NONE; 942 max_bio_size = DRBD_MAX_BIO_SIZE; /* ... multiple BIOs per peer_request */ 943 } 944 945 if (peer_device->connection->agreed_pro_version <= 94) 946 max_bio_size = min(max_bio_size, DRBD_MAX_SIZE_H80_PACKET); 947 else if (peer_device->connection->agreed_pro_version < 100) 948 max_bio_size = min(max_bio_size, DRBD_MAX_BIO_SIZE_P95); 949 950 p->d_size = cpu_to_be64(d_size); 951 p->u_size = cpu_to_be64(u_size); 952 if (trigger_reply) 953 p->c_size = 0; 954 else 955 p->c_size = cpu_to_be64(get_capacity(device->vdisk)); 956 p->max_bio_size = cpu_to_be32(max_bio_size); 957 p->queue_order_type = cpu_to_be16(q_order_type); 958 p->dds_flags = cpu_to_be16(flags); 959 960 return drbd_send_command(peer_device, sock, P_SIZES, packet_size, NULL, 0); 961} 962 963/** 964 * drbd_send_current_state() - Sends the drbd state to the peer 965 * @peer_device: DRBD peer device. 966 */ 967int drbd_send_current_state(struct drbd_peer_device *peer_device) 968{ 969 struct drbd_socket *sock; 970 struct p_state *p; 971 972 sock = &peer_device->connection->data; 973 p = drbd_prepare_command(peer_device, sock); 974 if (!p) 975 return -EIO; 976 p->state = cpu_to_be32(peer_device->device->state.i); /* Within the send mutex */ 977 return drbd_send_command(peer_device, sock, P_STATE, sizeof(*p), NULL, 0); 978} 979 980/** 981 * drbd_send_state() - After a state change, sends the new state to the peer 982 * @peer_device: DRBD peer device. 983 * @state: the state to send, not necessarily the current state. 984 * 985 * Each state change queues an "after_state_ch" work, which will eventually 986 * send the resulting new state to the peer. If more state changes happen 987 * between queuing and processing of the after_state_ch work, we still 988 * want to send each intermediary state in the order it occurred. 989 */ 990int drbd_send_state(struct drbd_peer_device *peer_device, union drbd_state state) 991{ 992 struct drbd_socket *sock; 993 struct p_state *p; 994 995 sock = &peer_device->connection->data; 996 p = drbd_prepare_command(peer_device, sock); 997 if (!p) 998 return -EIO; 999 p->state = cpu_to_be32(state.i); /* Within the send mutex */ 1000 return drbd_send_command(peer_device, sock, P_STATE, sizeof(*p), NULL, 0); 1001} 1002 1003int drbd_send_state_req(struct drbd_peer_device *peer_device, union drbd_state mask, union drbd_state val) 1004{ 1005 struct drbd_socket *sock; 1006 struct p_req_state *p; 1007 1008 sock = &peer_device->connection->data; 1009 p = drbd_prepare_command(peer_device, sock); 1010 if (!p) 1011 return -EIO; 1012 p->mask = cpu_to_be32(mask.i); 1013 p->val = cpu_to_be32(val.i); 1014 return drbd_send_command(peer_device, sock, P_STATE_CHG_REQ, sizeof(*p), NULL, 0); 1015} 1016 1017int conn_send_state_req(struct drbd_connection *connection, union drbd_state mask, union drbd_state val) 1018{ 1019 enum drbd_packet cmd; 1020 struct drbd_socket *sock; 1021 struct p_req_state *p; 1022 1023 cmd = connection->agreed_pro_version < 100 ? P_STATE_CHG_REQ : P_CONN_ST_CHG_REQ; 1024 sock = &connection->data; 1025 p = conn_prepare_command(connection, sock); 1026 if (!p) 1027 return -EIO; 1028 p->mask = cpu_to_be32(mask.i); 1029 p->val = cpu_to_be32(val.i); 1030 return conn_send_command(connection, sock, cmd, sizeof(*p), NULL, 0); 1031} 1032 1033void drbd_send_sr_reply(struct drbd_peer_device *peer_device, enum drbd_state_rv retcode) 1034{ 1035 struct drbd_socket *sock; 1036 struct p_req_state_reply *p; 1037 1038 sock = &peer_device->connection->meta; 1039 p = drbd_prepare_command(peer_device, sock); 1040 if (p) { 1041 p->retcode = cpu_to_be32(retcode); 1042 drbd_send_command(peer_device, sock, P_STATE_CHG_REPLY, sizeof(*p), NULL, 0); 1043 } 1044} 1045 1046void conn_send_sr_reply(struct drbd_connection *connection, enum drbd_state_rv retcode) 1047{ 1048 struct drbd_socket *sock; 1049 struct p_req_state_reply *p; 1050 enum drbd_packet cmd = connection->agreed_pro_version < 100 ? P_STATE_CHG_REPLY : P_CONN_ST_CHG_REPLY; 1051 1052 sock = &connection->meta; 1053 p = conn_prepare_command(connection, sock); 1054 if (p) { 1055 p->retcode = cpu_to_be32(retcode); 1056 conn_send_command(connection, sock, cmd, sizeof(*p), NULL, 0); 1057 } 1058} 1059 1060static void dcbp_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code) 1061{ 1062 BUG_ON(code & ~0xf); 1063 p->encoding = (p->encoding & ~0xf) | code; 1064} 1065 1066static void dcbp_set_start(struct p_compressed_bm *p, int set) 1067{ 1068 p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0); 1069} 1070 1071static void dcbp_set_pad_bits(struct p_compressed_bm *p, int n) 1072{ 1073 BUG_ON(n & ~0x7); 1074 p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4); 1075} 1076 1077static int fill_bitmap_rle_bits(struct drbd_device *device, 1078 struct p_compressed_bm *p, 1079 unsigned int size, 1080 struct bm_xfer_ctx *c) 1081{ 1082 struct bitstream bs; 1083 unsigned long plain_bits; 1084 unsigned long tmp; 1085 unsigned long rl; 1086 unsigned len; 1087 unsigned toggle; 1088 int bits, use_rle; 1089 1090 /* may we use this feature? */ 1091 rcu_read_lock(); 1092 use_rle = rcu_dereference(first_peer_device(device)->connection->net_conf)->use_rle; 1093 rcu_read_unlock(); 1094 if (!use_rle || first_peer_device(device)->connection->agreed_pro_version < 90) 1095 return 0; 1096 1097 if (c->bit_offset >= c->bm_bits) 1098 return 0; /* nothing to do. */ 1099 1100 /* use at most thus many bytes */ 1101 bitstream_init(&bs, p->code, size, 0); 1102 memset(p->code, 0, size); 1103 /* plain bits covered in this code string */ 1104 plain_bits = 0; 1105 1106 /* p->encoding & 0x80 stores whether the first run length is set. 1107 * bit offset is implicit. 1108 * start with toggle == 2 to be able to tell the first iteration */ 1109 toggle = 2; 1110 1111 /* see how much plain bits we can stuff into one packet 1112 * using RLE and VLI. */ 1113 do { 1114 tmp = (toggle == 0) ? _drbd_bm_find_next_zero(device, c->bit_offset) 1115 : _drbd_bm_find_next(device, c->bit_offset); 1116 if (tmp == -1UL) 1117 tmp = c->bm_bits; 1118 rl = tmp - c->bit_offset; 1119 1120 if (toggle == 2) { /* first iteration */ 1121 if (rl == 0) { 1122 /* the first checked bit was set, 1123 * store start value, */ 1124 dcbp_set_start(p, 1); 1125 /* but skip encoding of zero run length */ 1126 toggle = !toggle; 1127 continue; 1128 } 1129 dcbp_set_start(p, 0); 1130 } 1131 1132 /* paranoia: catch zero runlength. 1133 * can only happen if bitmap is modified while we scan it. */ 1134 if (rl == 0) { 1135 drbd_err(device, "unexpected zero runlength while encoding bitmap " 1136 "t:%u bo:%lu\n", toggle, c->bit_offset); 1137 return -1; 1138 } 1139 1140 bits = vli_encode_bits(&bs, rl); 1141 if (bits == -ENOBUFS) /* buffer full */ 1142 break; 1143 if (bits <= 0) { 1144 drbd_err(device, "error while encoding bitmap: %d\n", bits); 1145 return 0; 1146 } 1147 1148 toggle = !toggle; 1149 plain_bits += rl; 1150 c->bit_offset = tmp; 1151 } while (c->bit_offset < c->bm_bits); 1152 1153 len = bs.cur.b - p->code + !!bs.cur.bit; 1154 1155 if (plain_bits < (len << 3)) { 1156 /* incompressible with this method. 1157 * we need to rewind both word and bit position. */ 1158 c->bit_offset -= plain_bits; 1159 bm_xfer_ctx_bit_to_word_offset(c); 1160 c->bit_offset = c->word_offset * BITS_PER_LONG; 1161 return 0; 1162 } 1163 1164 /* RLE + VLI was able to compress it just fine. 1165 * update c->word_offset. */ 1166 bm_xfer_ctx_bit_to_word_offset(c); 1167 1168 /* store pad_bits */ 1169 dcbp_set_pad_bits(p, (8 - bs.cur.bit) & 0x7); 1170 1171 return len; 1172} 1173 1174/* 1175 * send_bitmap_rle_or_plain 1176 * 1177 * Return 0 when done, 1 when another iteration is needed, and a negative error 1178 * code upon failure. 1179 */ 1180static int 1181send_bitmap_rle_or_plain(struct drbd_peer_device *peer_device, struct bm_xfer_ctx *c) 1182{ 1183 struct drbd_device *device = peer_device->device; 1184 struct drbd_socket *sock = &peer_device->connection->data; 1185 unsigned int header_size = drbd_header_size(peer_device->connection); 1186 struct p_compressed_bm *p = sock->sbuf + header_size; 1187 int len, err; 1188 1189 len = fill_bitmap_rle_bits(device, p, 1190 DRBD_SOCKET_BUFFER_SIZE - header_size - sizeof(*p), c); 1191 if (len < 0) 1192 return -EIO; 1193 1194 if (len) { 1195 dcbp_set_code(p, RLE_VLI_Bits); 1196 err = __send_command(peer_device->connection, device->vnr, sock, 1197 P_COMPRESSED_BITMAP, sizeof(*p) + len, 1198 NULL, 0); 1199 c->packets[0]++; 1200 c->bytes[0] += header_size + sizeof(*p) + len; 1201 1202 if (c->bit_offset >= c->bm_bits) 1203 len = 0; /* DONE */ 1204 } else { 1205 /* was not compressible. 1206 * send a buffer full of plain text bits instead. */ 1207 unsigned int data_size; 1208 unsigned long num_words; 1209 unsigned long *p = sock->sbuf + header_size; 1210 1211 data_size = DRBD_SOCKET_BUFFER_SIZE - header_size; 1212 num_words = min_t(size_t, data_size / sizeof(*p), 1213 c->bm_words - c->word_offset); 1214 len = num_words * sizeof(*p); 1215 if (len) 1216 drbd_bm_get_lel(device, c->word_offset, num_words, p); 1217 err = __send_command(peer_device->connection, device->vnr, sock, P_BITMAP, 1218 len, NULL, 0); 1219 c->word_offset += num_words; 1220 c->bit_offset = c->word_offset * BITS_PER_LONG; 1221 1222 c->packets[1]++; 1223 c->bytes[1] += header_size + len; 1224 1225 if (c->bit_offset > c->bm_bits) 1226 c->bit_offset = c->bm_bits; 1227 } 1228 if (!err) { 1229 if (len == 0) { 1230 INFO_bm_xfer_stats(peer_device, "send", c); 1231 return 0; 1232 } else 1233 return 1; 1234 } 1235 return -EIO; 1236} 1237 1238/* See the comment at receive_bitmap() */ 1239static int _drbd_send_bitmap(struct drbd_device *device, 1240 struct drbd_peer_device *peer_device) 1241{ 1242 struct bm_xfer_ctx c; 1243 int err; 1244 1245 if (!expect(device, device->bitmap)) 1246 return false; 1247 1248 if (get_ldev(device)) { 1249 if (drbd_md_test_flag(device->ldev, MDF_FULL_SYNC)) { 1250 drbd_info(device, "Writing the whole bitmap, MDF_FullSync was set.\n"); 1251 drbd_bm_set_all(device); 1252 if (drbd_bm_write(device, peer_device)) { 1253 /* write_bm did fail! Leave full sync flag set in Meta P_DATA 1254 * but otherwise process as per normal - need to tell other 1255 * side that a full resync is required! */ 1256 drbd_err(device, "Failed to write bitmap to disk!\n"); 1257 } else { 1258 drbd_md_clear_flag(device, MDF_FULL_SYNC); 1259 drbd_md_sync(device); 1260 } 1261 } 1262 put_ldev(device); 1263 } 1264 1265 c = (struct bm_xfer_ctx) { 1266 .bm_bits = drbd_bm_bits(device), 1267 .bm_words = drbd_bm_words(device), 1268 }; 1269 1270 do { 1271 err = send_bitmap_rle_or_plain(peer_device, &c); 1272 } while (err > 0); 1273 1274 return err == 0; 1275} 1276 1277int drbd_send_bitmap(struct drbd_device *device, struct drbd_peer_device *peer_device) 1278{ 1279 struct drbd_socket *sock = &peer_device->connection->data; 1280 int err = -1; 1281 1282 mutex_lock(&sock->mutex); 1283 if (sock->socket) 1284 err = !_drbd_send_bitmap(device, peer_device); 1285 mutex_unlock(&sock->mutex); 1286 return err; 1287} 1288 1289void drbd_send_b_ack(struct drbd_connection *connection, u32 barrier_nr, u32 set_size) 1290{ 1291 struct drbd_socket *sock; 1292 struct p_barrier_ack *p; 1293 1294 if (connection->cstate < C_WF_REPORT_PARAMS) 1295 return; 1296 1297 sock = &connection->meta; 1298 p = conn_prepare_command(connection, sock); 1299 if (!p) 1300 return; 1301 p->barrier = barrier_nr; 1302 p->set_size = cpu_to_be32(set_size); 1303 conn_send_command(connection, sock, P_BARRIER_ACK, sizeof(*p), NULL, 0); 1304} 1305 1306/** 1307 * _drbd_send_ack() - Sends an ack packet 1308 * @peer_device: DRBD peer device. 1309 * @cmd: Packet command code. 1310 * @sector: sector, needs to be in big endian byte order 1311 * @blksize: size in byte, needs to be in big endian byte order 1312 * @block_id: Id, big endian byte order 1313 */ 1314static int _drbd_send_ack(struct drbd_peer_device *peer_device, enum drbd_packet cmd, 1315 u64 sector, u32 blksize, u64 block_id) 1316{ 1317 struct drbd_socket *sock; 1318 struct p_block_ack *p; 1319 1320 if (peer_device->device->state.conn < C_CONNECTED) 1321 return -EIO; 1322 1323 sock = &peer_device->connection->meta; 1324 p = drbd_prepare_command(peer_device, sock); 1325 if (!p) 1326 return -EIO; 1327 p->sector = sector; 1328 p->block_id = block_id; 1329 p->blksize = blksize; 1330 p->seq_num = cpu_to_be32(atomic_inc_return(&peer_device->device->packet_seq)); 1331 return drbd_send_command(peer_device, sock, cmd, sizeof(*p), NULL, 0); 1332} 1333 1334/* dp->sector and dp->block_id already/still in network byte order, 1335 * data_size is payload size according to dp->head, 1336 * and may need to be corrected for digest size. */ 1337void drbd_send_ack_dp(struct drbd_peer_device *peer_device, enum drbd_packet cmd, 1338 struct p_data *dp, int data_size) 1339{ 1340 if (peer_device->connection->peer_integrity_tfm) 1341 data_size -= crypto_shash_digestsize(peer_device->connection->peer_integrity_tfm); 1342 _drbd_send_ack(peer_device, cmd, dp->sector, cpu_to_be32(data_size), 1343 dp->block_id); 1344} 1345 1346void drbd_send_ack_rp(struct drbd_peer_device *peer_device, enum drbd_packet cmd, 1347 struct p_block_req *rp) 1348{ 1349 _drbd_send_ack(peer_device, cmd, rp->sector, rp->blksize, rp->block_id); 1350} 1351 1352/** 1353 * drbd_send_ack() - Sends an ack packet 1354 * @peer_device: DRBD peer device 1355 * @cmd: packet command code 1356 * @peer_req: peer request 1357 */ 1358int drbd_send_ack(struct drbd_peer_device *peer_device, enum drbd_packet cmd, 1359 struct drbd_peer_request *peer_req) 1360{ 1361 return _drbd_send_ack(peer_device, cmd, 1362 cpu_to_be64(peer_req->i.sector), 1363 cpu_to_be32(peer_req->i.size), 1364 peer_req->block_id); 1365} 1366 1367/* This function misuses the block_id field to signal if the blocks 1368 * are is sync or not. */ 1369int drbd_send_ack_ex(struct drbd_peer_device *peer_device, enum drbd_packet cmd, 1370 sector_t sector, int blksize, u64 block_id) 1371{ 1372 return _drbd_send_ack(peer_device, cmd, 1373 cpu_to_be64(sector), 1374 cpu_to_be32(blksize), 1375 cpu_to_be64(block_id)); 1376} 1377 1378int drbd_send_rs_deallocated(struct drbd_peer_device *peer_device, 1379 struct drbd_peer_request *peer_req) 1380{ 1381 struct drbd_socket *sock; 1382 struct p_block_desc *p; 1383 1384 sock = &peer_device->connection->data; 1385 p = drbd_prepare_command(peer_device, sock); 1386 if (!p) 1387 return -EIO; 1388 p->sector = cpu_to_be64(peer_req->i.sector); 1389 p->blksize = cpu_to_be32(peer_req->i.size); 1390 p->pad = 0; 1391 return drbd_send_command(peer_device, sock, P_RS_DEALLOCATED, sizeof(*p), NULL, 0); 1392} 1393 1394int drbd_send_drequest(struct drbd_peer_device *peer_device, int cmd, 1395 sector_t sector, int size, u64 block_id) 1396{ 1397 struct drbd_socket *sock; 1398 struct p_block_req *p; 1399 1400 sock = &peer_device->connection->data; 1401 p = drbd_prepare_command(peer_device, sock); 1402 if (!p) 1403 return -EIO; 1404 p->sector = cpu_to_be64(sector); 1405 p->block_id = block_id; 1406 p->blksize = cpu_to_be32(size); 1407 return drbd_send_command(peer_device, sock, cmd, sizeof(*p), NULL, 0); 1408} 1409 1410int drbd_send_drequest_csum(struct drbd_peer_device *peer_device, sector_t sector, int size, 1411 void *digest, int digest_size, enum drbd_packet cmd) 1412{ 1413 struct drbd_socket *sock; 1414 struct p_block_req *p; 1415 1416 /* FIXME: Put the digest into the preallocated socket buffer. */ 1417 1418 sock = &peer_device->connection->data; 1419 p = drbd_prepare_command(peer_device, sock); 1420 if (!p) 1421 return -EIO; 1422 p->sector = cpu_to_be64(sector); 1423 p->block_id = ID_SYNCER /* unused */; 1424 p->blksize = cpu_to_be32(size); 1425 return drbd_send_command(peer_device, sock, cmd, sizeof(*p), digest, digest_size); 1426} 1427 1428int drbd_send_ov_request(struct drbd_peer_device *peer_device, sector_t sector, int size) 1429{ 1430 struct drbd_socket *sock; 1431 struct p_block_req *p; 1432 1433 sock = &peer_device->connection->data; 1434 p = drbd_prepare_command(peer_device, sock); 1435 if (!p) 1436 return -EIO; 1437 p->sector = cpu_to_be64(sector); 1438 p->block_id = ID_SYNCER /* unused */; 1439 p->blksize = cpu_to_be32(size); 1440 return drbd_send_command(peer_device, sock, P_OV_REQUEST, sizeof(*p), NULL, 0); 1441} 1442 1443/* called on sndtimeo 1444 * returns false if we should retry, 1445 * true if we think connection is dead 1446 */ 1447static int we_should_drop_the_connection(struct drbd_connection *connection, struct socket *sock) 1448{ 1449 int drop_it; 1450 /* long elapsed = (long)(jiffies - device->last_received); */ 1451 1452 drop_it = connection->meta.socket == sock 1453 || !connection->ack_receiver.task 1454 || get_t_state(&connection->ack_receiver) != RUNNING 1455 || connection->cstate < C_WF_REPORT_PARAMS; 1456 1457 if (drop_it) 1458 return true; 1459 1460 drop_it = !--connection->ko_count; 1461 if (!drop_it) { 1462 drbd_err(connection, "[%s/%d] sock_sendmsg time expired, ko = %u\n", 1463 current->comm, current->pid, connection->ko_count); 1464 request_ping(connection); 1465 } 1466 1467 return drop_it; /* && (device->state == R_PRIMARY) */; 1468} 1469 1470static void drbd_update_congested(struct drbd_connection *connection) 1471{ 1472 struct sock *sk = connection->data.socket->sk; 1473 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5) 1474 set_bit(NET_CONGESTED, &connection->flags); 1475} 1476 1477/* The idea of sendpage seems to be to put some kind of reference 1478 * to the page into the skb, and to hand it over to the NIC. In 1479 * this process get_page() gets called. 1480 * 1481 * As soon as the page was really sent over the network put_page() 1482 * gets called by some part of the network layer. [ NIC driver? ] 1483 * 1484 * [ get_page() / put_page() increment/decrement the count. If count 1485 * reaches 0 the page will be freed. ] 1486 * 1487 * This works nicely with pages from FSs. 1488 * But this means that in protocol A we might signal IO completion too early! 1489 * 1490 * In order not to corrupt data during a resync we must make sure 1491 * that we do not reuse our own buffer pages (EEs) to early, therefore 1492 * we have the net_ee list. 1493 * 1494 * XFS seems to have problems, still, it submits pages with page_count == 0! 1495 * As a workaround, we disable sendpage on pages 1496 * with page_count == 0 or PageSlab. 1497 */ 1498static int _drbd_no_send_page(struct drbd_peer_device *peer_device, struct page *page, 1499 int offset, size_t size, unsigned msg_flags) 1500{ 1501 struct socket *socket; 1502 void *addr; 1503 int err; 1504 1505 socket = peer_device->connection->data.socket; 1506 addr = kmap(page) + offset; 1507 err = drbd_send_all(peer_device->connection, socket, addr, size, msg_flags); 1508 kunmap(page); 1509 if (!err) 1510 peer_device->device->send_cnt += size >> 9; 1511 return err; 1512} 1513 1514static int _drbd_send_page(struct drbd_peer_device *peer_device, struct page *page, 1515 int offset, size_t size, unsigned msg_flags) 1516{ 1517 struct socket *socket = peer_device->connection->data.socket; 1518 struct msghdr msg = { .msg_flags = msg_flags, }; 1519 struct bio_vec bvec; 1520 int len = size; 1521 int err = -EIO; 1522 1523 /* e.g. XFS meta- & log-data is in slab pages, which have a 1524 * page_count of 0 and/or have PageSlab() set. 1525 * we cannot use send_page for those, as that does get_page(); 1526 * put_page(); and would cause either a VM_BUG directly, or 1527 * __page_cache_release a page that would actually still be referenced 1528 * by someone, leading to some obscure delayed Oops somewhere else. */ 1529 if (!drbd_disable_sendpage && sendpages_ok(page, len, offset)) 1530 msg.msg_flags |= MSG_NOSIGNAL | MSG_SPLICE_PAGES; 1531 1532 drbd_update_congested(peer_device->connection); 1533 do { 1534 int sent; 1535 1536 bvec_set_page(&bvec, page, len, offset); 1537 iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, len); 1538 1539 sent = sock_sendmsg(socket, &msg); 1540 if (sent <= 0) { 1541 if (sent == -EAGAIN) { 1542 if (we_should_drop_the_connection(peer_device->connection, socket)) 1543 break; 1544 continue; 1545 } 1546 drbd_warn(peer_device->device, "%s: size=%d len=%d sent=%d\n", 1547 __func__, (int)size, len, sent); 1548 if (sent < 0) 1549 err = sent; 1550 break; 1551 } 1552 len -= sent; 1553 offset += sent; 1554 } while (len > 0 /* THINK && device->cstate >= C_CONNECTED*/); 1555 clear_bit(NET_CONGESTED, &peer_device->connection->flags); 1556 1557 if (len == 0) { 1558 err = 0; 1559 peer_device->device->send_cnt += size >> 9; 1560 } 1561 return err; 1562} 1563 1564static int _drbd_send_bio(struct drbd_peer_device *peer_device, struct bio *bio) 1565{ 1566 struct bio_vec bvec; 1567 struct bvec_iter iter; 1568 1569 /* hint all but last page with MSG_MORE */ 1570 bio_for_each_segment(bvec, bio, iter) { 1571 int err; 1572 1573 err = _drbd_no_send_page(peer_device, bvec.bv_page, 1574 bvec.bv_offset, bvec.bv_len, 1575 bio_iter_last(bvec, iter) 1576 ? 0 : MSG_MORE); 1577 if (err) 1578 return err; 1579 } 1580 return 0; 1581} 1582 1583static int _drbd_send_zc_bio(struct drbd_peer_device *peer_device, struct bio *bio) 1584{ 1585 struct bio_vec bvec; 1586 struct bvec_iter iter; 1587 1588 /* hint all but last page with MSG_MORE */ 1589 bio_for_each_segment(bvec, bio, iter) { 1590 int err; 1591 1592 err = _drbd_send_page(peer_device, bvec.bv_page, 1593 bvec.bv_offset, bvec.bv_len, 1594 bio_iter_last(bvec, iter) ? 0 : MSG_MORE); 1595 if (err) 1596 return err; 1597 } 1598 return 0; 1599} 1600 1601static int _drbd_send_zc_ee(struct drbd_peer_device *peer_device, 1602 struct drbd_peer_request *peer_req) 1603{ 1604 bool use_sendpage = !(peer_req->flags & EE_RELEASE_TO_MEMPOOL); 1605 struct page *page = peer_req->pages; 1606 unsigned len = peer_req->i.size; 1607 int err; 1608 1609 /* hint all but last page with MSG_MORE */ 1610 page_chain_for_each(page) { 1611 unsigned l = min_t(unsigned, len, PAGE_SIZE); 1612 1613 if (likely(use_sendpage)) 1614 err = _drbd_send_page(peer_device, page, 0, l, 1615 page_chain_next(page) ? MSG_MORE : 0); 1616 else 1617 err = _drbd_no_send_page(peer_device, page, 0, l, 1618 page_chain_next(page) ? MSG_MORE : 0); 1619 1620 if (err) 1621 return err; 1622 len -= l; 1623 } 1624 return 0; 1625} 1626 1627static u32 bio_flags_to_wire(struct drbd_connection *connection, 1628 struct bio *bio) 1629{ 1630 if (connection->agreed_pro_version >= 95) 1631 return (bio->bi_opf & REQ_SYNC ? DP_RW_SYNC : 0) | 1632 (bio->bi_opf & REQ_FUA ? DP_FUA : 0) | 1633 (bio->bi_opf & REQ_PREFLUSH ? DP_FLUSH : 0) | 1634 (bio_op(bio) == REQ_OP_DISCARD ? DP_DISCARD : 0) | 1635 (bio_op(bio) == REQ_OP_WRITE_ZEROES ? 1636 ((connection->agreed_features & DRBD_FF_WZEROES) ? 1637 (DP_ZEROES |(!(bio->bi_opf & REQ_NOUNMAP) ? DP_DISCARD : 0)) 1638 : DP_DISCARD) 1639 : 0); 1640 else 1641 return bio->bi_opf & REQ_SYNC ? DP_RW_SYNC : 0; 1642} 1643 1644/* Used to send write or TRIM aka REQ_OP_DISCARD requests 1645 * R_PRIMARY -> Peer (P_DATA, P_TRIM) 1646 */ 1647int drbd_send_dblock(struct drbd_peer_device *peer_device, struct drbd_request *req) 1648{ 1649 struct drbd_device *device = peer_device->device; 1650 struct drbd_socket *sock; 1651 struct p_data *p; 1652 void *digest_out; 1653 unsigned int dp_flags = 0; 1654 int digest_size; 1655 int err; 1656 1657 sock = &peer_device->connection->data; 1658 p = drbd_prepare_command(peer_device, sock); 1659 digest_size = peer_device->connection->integrity_tfm ? 1660 crypto_shash_digestsize(peer_device->connection->integrity_tfm) : 0; 1661 1662 if (!p) 1663 return -EIO; 1664 p->sector = cpu_to_be64(req->i.sector); 1665 p->block_id = (unsigned long)req; 1666 p->seq_num = cpu_to_be32(atomic_inc_return(&device->packet_seq)); 1667 dp_flags = bio_flags_to_wire(peer_device->connection, req->master_bio); 1668 if (device->state.conn >= C_SYNC_SOURCE && 1669 device->state.conn <= C_PAUSED_SYNC_T) 1670 dp_flags |= DP_MAY_SET_IN_SYNC; 1671 if (peer_device->connection->agreed_pro_version >= 100) { 1672 if (req->rq_state & RQ_EXP_RECEIVE_ACK) 1673 dp_flags |= DP_SEND_RECEIVE_ACK; 1674 /* During resync, request an explicit write ack, 1675 * even in protocol != C */ 1676 if (req->rq_state & RQ_EXP_WRITE_ACK 1677 || (dp_flags & DP_MAY_SET_IN_SYNC)) 1678 dp_flags |= DP_SEND_WRITE_ACK; 1679 } 1680 p->dp_flags = cpu_to_be32(dp_flags); 1681 1682 if (dp_flags & (DP_DISCARD|DP_ZEROES)) { 1683 enum drbd_packet cmd = (dp_flags & DP_ZEROES) ? P_ZEROES : P_TRIM; 1684 struct p_trim *t = (struct p_trim*)p; 1685 t->size = cpu_to_be32(req->i.size); 1686 err = __send_command(peer_device->connection, device->vnr, sock, cmd, sizeof(*t), NULL, 0); 1687 goto out; 1688 } 1689 digest_out = p + 1; 1690 1691 /* our digest is still only over the payload. 1692 * TRIM does not carry any payload. */ 1693 if (digest_size) 1694 drbd_csum_bio(peer_device->connection->integrity_tfm, req->master_bio, digest_out); 1695 err = __send_command(peer_device->connection, device->vnr, sock, P_DATA, 1696 sizeof(*p) + digest_size, NULL, req->i.size); 1697 if (!err) { 1698 /* For protocol A, we have to memcpy the payload into 1699 * socket buffers, as we may complete right away 1700 * as soon as we handed it over to tcp, at which point the data 1701 * pages may become invalid. 1702 * 1703 * For data-integrity enabled, we copy it as well, so we can be 1704 * sure that even if the bio pages may still be modified, it 1705 * won't change the data on the wire, thus if the digest checks 1706 * out ok after sending on this side, but does not fit on the 1707 * receiving side, we sure have detected corruption elsewhere. 1708 */ 1709 if (!(req->rq_state & (RQ_EXP_RECEIVE_ACK | RQ_EXP_WRITE_ACK)) || digest_size) 1710 err = _drbd_send_bio(peer_device, req->master_bio); 1711 else 1712 err = _drbd_send_zc_bio(peer_device, req->master_bio); 1713 1714 /* double check digest, sometimes buffers have been modified in flight. */ 1715 if (digest_size > 0 && digest_size <= 64) { 1716 /* 64 byte, 512 bit, is the largest digest size 1717 * currently supported in kernel crypto. */ 1718 unsigned char digest[64]; 1719 drbd_csum_bio(peer_device->connection->integrity_tfm, req->master_bio, digest); 1720 if (memcmp(p + 1, digest, digest_size)) { 1721 drbd_warn(device, 1722 "Digest mismatch, buffer modified by upper layers during write: %llus +%u\n", 1723 (unsigned long long)req->i.sector, req->i.size); 1724 } 1725 } /* else if (digest_size > 64) { 1726 ... Be noisy about digest too large ... 1727 } */ 1728 } 1729out: 1730 mutex_unlock(&sock->mutex); /* locked by drbd_prepare_command() */ 1731 1732 return err; 1733} 1734 1735/* answer packet, used to send data back for read requests: 1736 * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY) 1737 * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY) 1738 */ 1739int drbd_send_block(struct drbd_peer_device *peer_device, enum drbd_packet cmd, 1740 struct drbd_peer_request *peer_req) 1741{ 1742 struct drbd_device *device = peer_device->device; 1743 struct drbd_socket *sock; 1744 struct p_data *p; 1745 int err; 1746 int digest_size; 1747 1748 sock = &peer_device->connection->data; 1749 p = drbd_prepare_command(peer_device, sock); 1750 1751 digest_size = peer_device->connection->integrity_tfm ? 1752 crypto_shash_digestsize(peer_device->connection->integrity_tfm) : 0; 1753 1754 if (!p) 1755 return -EIO; 1756 p->sector = cpu_to_be64(peer_req->i.sector); 1757 p->block_id = peer_req->block_id; 1758 p->seq_num = 0; /* unused */ 1759 p->dp_flags = 0; 1760 if (digest_size) 1761 drbd_csum_ee(peer_device->connection->integrity_tfm, peer_req, p + 1); 1762 err = __send_command(peer_device->connection, device->vnr, sock, cmd, sizeof(*p) + digest_size, NULL, peer_req->i.size); 1763 if (!err) 1764 err = _drbd_send_zc_ee(peer_device, peer_req); 1765 mutex_unlock(&sock->mutex); /* locked by drbd_prepare_command() */ 1766 1767 return err; 1768} 1769 1770int drbd_send_out_of_sync(struct drbd_peer_device *peer_device, struct drbd_request *req) 1771{ 1772 struct drbd_socket *sock; 1773 struct p_block_desc *p; 1774 1775 sock = &peer_device->connection->data; 1776 p = drbd_prepare_command(peer_device, sock); 1777 if (!p) 1778 return -EIO; 1779 p->sector = cpu_to_be64(req->i.sector); 1780 p->blksize = cpu_to_be32(req->i.size); 1781 return drbd_send_command(peer_device, sock, P_OUT_OF_SYNC, sizeof(*p), NULL, 0); 1782} 1783 1784/* 1785 drbd_send distinguishes two cases: 1786 1787 Packets sent via the data socket "sock" 1788 and packets sent via the meta data socket "msock" 1789 1790 sock msock 1791 -----------------+-------------------------+------------------------------ 1792 timeout conf.timeout / 2 conf.timeout / 2 1793 timeout action send a ping via msock Abort communication 1794 and close all sockets 1795*/ 1796 1797/* 1798 * you must have down()ed the appropriate [m]sock_mutex elsewhere! 1799 */ 1800int drbd_send(struct drbd_connection *connection, struct socket *sock, 1801 void *buf, size_t size, unsigned msg_flags) 1802{ 1803 struct kvec iov = {.iov_base = buf, .iov_len = size}; 1804 struct msghdr msg = {.msg_flags = msg_flags | MSG_NOSIGNAL}; 1805 int rv, sent = 0; 1806 1807 if (!sock) 1808 return -EBADR; 1809 1810 /* THINK if (signal_pending) return ... ? */ 1811 1812 iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, size); 1813 1814 if (sock == connection->data.socket) { 1815 rcu_read_lock(); 1816 connection->ko_count = rcu_dereference(connection->net_conf)->ko_count; 1817 rcu_read_unlock(); 1818 drbd_update_congested(connection); 1819 } 1820 do { 1821 rv = sock_sendmsg(sock, &msg); 1822 if (rv == -EAGAIN) { 1823 if (we_should_drop_the_connection(connection, sock)) 1824 break; 1825 else 1826 continue; 1827 } 1828 if (rv == -EINTR) { 1829 flush_signals(current); 1830 rv = 0; 1831 } 1832 if (rv < 0) 1833 break; 1834 sent += rv; 1835 } while (sent < size); 1836 1837 if (sock == connection->data.socket) 1838 clear_bit(NET_CONGESTED, &connection->flags); 1839 1840 if (rv <= 0) { 1841 if (rv != -EAGAIN) { 1842 drbd_err(connection, "%s_sendmsg returned %d\n", 1843 sock == connection->meta.socket ? "msock" : "sock", 1844 rv); 1845 conn_request_state(connection, NS(conn, C_BROKEN_PIPE), CS_HARD); 1846 } else 1847 conn_request_state(connection, NS(conn, C_TIMEOUT), CS_HARD); 1848 } 1849 1850 return sent; 1851} 1852 1853/* 1854 * drbd_send_all - Send an entire buffer 1855 * 1856 * Returns 0 upon success and a negative error value otherwise. 1857 */ 1858int drbd_send_all(struct drbd_connection *connection, struct socket *sock, void *buffer, 1859 size_t size, unsigned msg_flags) 1860{ 1861 int err; 1862 1863 err = drbd_send(connection, sock, buffer, size, msg_flags); 1864 if (err < 0) 1865 return err; 1866 if (err != size) 1867 return -EIO; 1868 return 0; 1869} 1870 1871static int drbd_open(struct gendisk *disk, blk_mode_t mode) 1872{ 1873 struct drbd_device *device = disk->private_data; 1874 unsigned long flags; 1875 int rv = 0; 1876 1877 mutex_lock(&drbd_main_mutex); 1878 spin_lock_irqsave(&device->resource->req_lock, flags); 1879 /* to have a stable device->state.role 1880 * and no race with updating open_cnt */ 1881 1882 if (device->state.role != R_PRIMARY) { 1883 if (mode & BLK_OPEN_WRITE) 1884 rv = -EROFS; 1885 else if (!drbd_allow_oos) 1886 rv = -EMEDIUMTYPE; 1887 } 1888 1889 if (!rv) 1890 device->open_cnt++; 1891 spin_unlock_irqrestore(&device->resource->req_lock, flags); 1892 mutex_unlock(&drbd_main_mutex); 1893 1894 return rv; 1895} 1896 1897static void drbd_release(struct gendisk *gd) 1898{ 1899 struct drbd_device *device = gd->private_data; 1900 1901 mutex_lock(&drbd_main_mutex); 1902 device->open_cnt--; 1903 mutex_unlock(&drbd_main_mutex); 1904} 1905 1906/* need to hold resource->req_lock */ 1907void drbd_queue_unplug(struct drbd_device *device) 1908{ 1909 if (device->state.pdsk >= D_INCONSISTENT && device->state.conn >= C_CONNECTED) { 1910 D_ASSERT(device, device->state.role == R_PRIMARY); 1911 if (test_and_clear_bit(UNPLUG_REMOTE, &device->flags)) { 1912 drbd_queue_work_if_unqueued( 1913 &first_peer_device(device)->connection->sender_work, 1914 &device->unplug_work); 1915 } 1916 } 1917} 1918 1919static void drbd_set_defaults(struct drbd_device *device) 1920{ 1921 /* Beware! The actual layout differs 1922 * between big endian and little endian */ 1923 device->state = (union drbd_dev_state) { 1924 { .role = R_SECONDARY, 1925 .peer = R_UNKNOWN, 1926 .conn = C_STANDALONE, 1927 .disk = D_DISKLESS, 1928 .pdsk = D_UNKNOWN, 1929 } }; 1930} 1931 1932void drbd_init_set_defaults(struct drbd_device *device) 1933{ 1934 /* the memset(,0,) did most of this. 1935 * note: only assignments, no allocation in here */ 1936 1937 drbd_set_defaults(device); 1938 1939 atomic_set(&device->ap_bio_cnt, 0); 1940 atomic_set(&device->ap_actlog_cnt, 0); 1941 atomic_set(&device->ap_pending_cnt, 0); 1942 atomic_set(&device->rs_pending_cnt, 0); 1943 atomic_set(&device->unacked_cnt, 0); 1944 atomic_set(&device->local_cnt, 0); 1945 atomic_set(&device->pp_in_use_by_net, 0); 1946 atomic_set(&device->rs_sect_in, 0); 1947 atomic_set(&device->rs_sect_ev, 0); 1948 atomic_set(&device->ap_in_flight, 0); 1949 atomic_set(&device->md_io.in_use, 0); 1950 1951 mutex_init(&device->own_state_mutex); 1952 device->state_mutex = &device->own_state_mutex; 1953 1954 spin_lock_init(&device->al_lock); 1955 spin_lock_init(&device->peer_seq_lock); 1956 1957 INIT_LIST_HEAD(&device->active_ee); 1958 INIT_LIST_HEAD(&device->sync_ee); 1959 INIT_LIST_HEAD(&device->done_ee); 1960 INIT_LIST_HEAD(&device->read_ee); 1961 INIT_LIST_HEAD(&device->resync_reads); 1962 INIT_LIST_HEAD(&device->resync_work.list); 1963 INIT_LIST_HEAD(&device->unplug_work.list); 1964 INIT_LIST_HEAD(&device->bm_io_work.w.list); 1965 INIT_LIST_HEAD(&device->pending_master_completion[0]); 1966 INIT_LIST_HEAD(&device->pending_master_completion[1]); 1967 INIT_LIST_HEAD(&device->pending_completion[0]); 1968 INIT_LIST_HEAD(&device->pending_completion[1]); 1969 1970 device->resync_work.cb = w_resync_timer; 1971 device->unplug_work.cb = w_send_write_hint; 1972 device->bm_io_work.w.cb = w_bitmap_io; 1973 1974 timer_setup(&device->resync_timer, resync_timer_fn, 0); 1975 timer_setup(&device->md_sync_timer, md_sync_timer_fn, 0); 1976 timer_setup(&device->start_resync_timer, start_resync_timer_fn, 0); 1977 timer_setup(&device->request_timer, request_timer_fn, 0); 1978 1979 init_waitqueue_head(&device->misc_wait); 1980 init_waitqueue_head(&device->state_wait); 1981 init_waitqueue_head(&device->ee_wait); 1982 init_waitqueue_head(&device->al_wait); 1983 init_waitqueue_head(&device->seq_wait); 1984 1985 device->resync_wenr = LC_FREE; 1986 device->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE; 1987 device->local_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE; 1988} 1989 1990void drbd_set_my_capacity(struct drbd_device *device, sector_t size) 1991{ 1992 char ppb[10]; 1993 1994 set_capacity_and_notify(device->vdisk, size); 1995 1996 drbd_info(device, "size = %s (%llu KB)\n", 1997 ppsize(ppb, size>>1), (unsigned long long)size>>1); 1998} 1999 2000void drbd_device_cleanup(struct drbd_device *device) 2001{ 2002 int i; 2003 if (first_peer_device(device)->connection->receiver.t_state != NONE) 2004 drbd_err(device, "ASSERT FAILED: receiver t_state == %d expected 0.\n", 2005 first_peer_device(device)->connection->receiver.t_state); 2006 2007 device->al_writ_cnt = 2008 device->bm_writ_cnt = 2009 device->read_cnt = 2010 device->recv_cnt = 2011 device->send_cnt = 2012 device->writ_cnt = 2013 device->p_size = 2014 device->rs_start = 2015 device->rs_total = 2016 device->rs_failed = 0; 2017 device->rs_last_events = 0; 2018 device->rs_last_sect_ev = 0; 2019 for (i = 0; i < DRBD_SYNC_MARKS; i++) { 2020 device->rs_mark_left[i] = 0; 2021 device->rs_mark_time[i] = 0; 2022 } 2023 D_ASSERT(device, first_peer_device(device)->connection->net_conf == NULL); 2024 2025 set_capacity_and_notify(device->vdisk, 0); 2026 if (device->bitmap) { 2027 /* maybe never allocated. */ 2028 drbd_bm_resize(device, 0, 1); 2029 drbd_bm_cleanup(device); 2030 } 2031 2032 drbd_backing_dev_free(device, device->ldev); 2033 device->ldev = NULL; 2034 2035 clear_bit(AL_SUSPENDED, &device->flags); 2036 2037 D_ASSERT(device, list_empty(&device->active_ee)); 2038 D_ASSERT(device, list_empty(&device->sync_ee)); 2039 D_ASSERT(device, list_empty(&device->done_ee)); 2040 D_ASSERT(device, list_empty(&device->read_ee)); 2041 D_ASSERT(device, list_empty(&device->resync_reads)); 2042 D_ASSERT(device, list_empty(&first_peer_device(device)->connection->sender_work.q)); 2043 D_ASSERT(device, list_empty(&device->resync_work.list)); 2044 D_ASSERT(device, list_empty(&device->unplug_work.list)); 2045 2046 drbd_set_defaults(device); 2047} 2048 2049 2050static void drbd_destroy_mempools(void) 2051{ 2052 /* D_ASSERT(device, atomic_read(&drbd_pp_vacant)==0); */ 2053 2054 bioset_exit(&drbd_io_bio_set); 2055 bioset_exit(&drbd_md_io_bio_set); 2056 mempool_exit(&drbd_buffer_page_pool); 2057 mempool_exit(&drbd_md_io_page_pool); 2058 mempool_exit(&drbd_ee_mempool); 2059 mempool_exit(&drbd_request_mempool); 2060 kmem_cache_destroy(drbd_ee_cache); 2061 kmem_cache_destroy(drbd_request_cache); 2062 kmem_cache_destroy(drbd_bm_ext_cache); 2063 kmem_cache_destroy(drbd_al_ext_cache); 2064 2065 drbd_ee_cache = NULL; 2066 drbd_request_cache = NULL; 2067 drbd_bm_ext_cache = NULL; 2068 drbd_al_ext_cache = NULL; 2069 2070 return; 2071} 2072 2073static int drbd_create_mempools(void) 2074{ 2075 const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * drbd_minor_count; 2076 int ret; 2077 2078 /* caches */ 2079 drbd_request_cache = kmem_cache_create( 2080 "drbd_req", sizeof(struct drbd_request), 0, 0, NULL); 2081 if (drbd_request_cache == NULL) 2082 goto Enomem; 2083 2084 drbd_ee_cache = kmem_cache_create( 2085 "drbd_ee", sizeof(struct drbd_peer_request), 0, 0, NULL); 2086 if (drbd_ee_cache == NULL) 2087 goto Enomem; 2088 2089 drbd_bm_ext_cache = kmem_cache_create( 2090 "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL); 2091 if (drbd_bm_ext_cache == NULL) 2092 goto Enomem; 2093 2094 drbd_al_ext_cache = kmem_cache_create( 2095 "drbd_al", sizeof(struct lc_element), 0, 0, NULL); 2096 if (drbd_al_ext_cache == NULL) 2097 goto Enomem; 2098 2099 /* mempools */ 2100 ret = bioset_init(&drbd_io_bio_set, BIO_POOL_SIZE, 0, 0); 2101 if (ret) 2102 goto Enomem; 2103 2104 ret = bioset_init(&drbd_md_io_bio_set, DRBD_MIN_POOL_PAGES, 0, 2105 BIOSET_NEED_BVECS); 2106 if (ret) 2107 goto Enomem; 2108 2109 ret = mempool_init_page_pool(&drbd_md_io_page_pool, DRBD_MIN_POOL_PAGES, 0); 2110 if (ret) 2111 goto Enomem; 2112 2113 ret = mempool_init_page_pool(&drbd_buffer_page_pool, number, 0); 2114 if (ret) 2115 goto Enomem; 2116 2117 ret = mempool_init_slab_pool(&drbd_request_mempool, number, 2118 drbd_request_cache); 2119 if (ret) 2120 goto Enomem; 2121 2122 ret = mempool_init_slab_pool(&drbd_ee_mempool, number, drbd_ee_cache); 2123 if (ret) 2124 goto Enomem; 2125 2126 return 0; 2127 2128Enomem: 2129 drbd_destroy_mempools(); /* in case we allocated some */ 2130 return -ENOMEM; 2131} 2132 2133static void drbd_release_all_peer_reqs(struct drbd_device *device) 2134{ 2135 int rr; 2136 2137 rr = drbd_free_peer_reqs(device, &device->active_ee); 2138 if (rr) 2139 drbd_err(device, "%d EEs in active list found!\n", rr); 2140 2141 rr = drbd_free_peer_reqs(device, &device->sync_ee); 2142 if (rr) 2143 drbd_err(device, "%d EEs in sync list found!\n", rr); 2144 2145 rr = drbd_free_peer_reqs(device, &device->read_ee); 2146 if (rr) 2147 drbd_err(device, "%d EEs in read list found!\n", rr); 2148 2149 rr = drbd_free_peer_reqs(device, &device->done_ee); 2150 if (rr) 2151 drbd_err(device, "%d EEs in done list found!\n", rr); 2152} 2153 2154/* caution. no locking. */ 2155void drbd_destroy_device(struct kref *kref) 2156{ 2157 struct drbd_device *device = container_of(kref, struct drbd_device, kref); 2158 struct drbd_resource *resource = device->resource; 2159 struct drbd_peer_device *peer_device, *tmp_peer_device; 2160 2161 timer_shutdown_sync(&device->request_timer); 2162 2163 /* paranoia asserts */ 2164 D_ASSERT(device, device->open_cnt == 0); 2165 /* end paranoia asserts */ 2166 2167 /* cleanup stuff that may have been allocated during 2168 * device (re-)configuration or state changes */ 2169 2170 drbd_backing_dev_free(device, device->ldev); 2171 device->ldev = NULL; 2172 2173 drbd_release_all_peer_reqs(device); 2174 2175 lc_destroy(device->act_log); 2176 lc_destroy(device->resync); 2177 2178 kfree(device->p_uuid); 2179 /* device->p_uuid = NULL; */ 2180 2181 if (device->bitmap) /* should no longer be there. */ 2182 drbd_bm_cleanup(device); 2183 __free_page(device->md_io.page); 2184 put_disk(device->vdisk); 2185 kfree(device->rs_plan_s); 2186 2187 /* not for_each_connection(connection, resource): 2188 * those may have been cleaned up and disassociated already. 2189 */ 2190 for_each_peer_device_safe(peer_device, tmp_peer_device, device) { 2191 kref_put(&peer_device->connection->kref, drbd_destroy_connection); 2192 kfree(peer_device); 2193 } 2194 if (device->submit.wq) 2195 destroy_workqueue(device->submit.wq); 2196 kfree(device); 2197 kref_put(&resource->kref, drbd_destroy_resource); 2198} 2199 2200/* One global retry thread, if we need to push back some bio and have it 2201 * reinserted through our make request function. 2202 */ 2203static struct retry_worker { 2204 struct workqueue_struct *wq; 2205 struct work_struct worker; 2206 2207 spinlock_t lock; 2208 struct list_head writes; 2209} retry; 2210 2211static void do_retry(struct work_struct *ws) 2212{ 2213 struct retry_worker *retry = container_of(ws, struct retry_worker, worker); 2214 LIST_HEAD(writes); 2215 struct drbd_request *req, *tmp; 2216 2217 spin_lock_irq(&retry->lock); 2218 list_splice_init(&retry->writes, &writes); 2219 spin_unlock_irq(&retry->lock); 2220 2221 list_for_each_entry_safe(req, tmp, &writes, tl_requests) { 2222 struct drbd_device *device = req->device; 2223 struct bio *bio = req->master_bio; 2224 bool expected; 2225 2226 expected = 2227 expect(device, atomic_read(&req->completion_ref) == 0) && 2228 expect(device, req->rq_state & RQ_POSTPONED) && 2229 expect(device, (req->rq_state & RQ_LOCAL_PENDING) == 0 || 2230 (req->rq_state & RQ_LOCAL_ABORTED) != 0); 2231 2232 if (!expected) 2233 drbd_err(device, "req=%p completion_ref=%d rq_state=%x\n", 2234 req, atomic_read(&req->completion_ref), 2235 req->rq_state); 2236 2237 /* We still need to put one kref associated with the 2238 * "completion_ref" going zero in the code path that queued it 2239 * here. The request object may still be referenced by a 2240 * frozen local req->private_bio, in case we force-detached. 2241 */ 2242 kref_put(&req->kref, drbd_req_destroy); 2243 2244 /* A single suspended or otherwise blocking device may stall 2245 * all others as well. Fortunately, this code path is to 2246 * recover from a situation that "should not happen": 2247 * concurrent writes in multi-primary setup. 2248 * In a "normal" lifecycle, this workqueue is supposed to be 2249 * destroyed without ever doing anything. 2250 * If it turns out to be an issue anyways, we can do per 2251 * resource (replication group) or per device (minor) retry 2252 * workqueues instead. 2253 */ 2254 2255 /* We are not just doing submit_bio_noacct(), 2256 * as we want to keep the start_time information. */ 2257 inc_ap_bio(device); 2258 __drbd_make_request(device, bio); 2259 } 2260} 2261 2262/* called via drbd_req_put_completion_ref(), 2263 * holds resource->req_lock */ 2264void drbd_restart_request(struct drbd_request *req) 2265{ 2266 unsigned long flags; 2267 spin_lock_irqsave(&retry.lock, flags); 2268 list_move_tail(&req->tl_requests, &retry.writes); 2269 spin_unlock_irqrestore(&retry.lock, flags); 2270 2271 /* Drop the extra reference that would otherwise 2272 * have been dropped by complete_master_bio. 2273 * do_retry() needs to grab a new one. */ 2274 dec_ap_bio(req->device); 2275 2276 queue_work(retry.wq, &retry.worker); 2277} 2278 2279void drbd_destroy_resource(struct kref *kref) 2280{ 2281 struct drbd_resource *resource = 2282 container_of(kref, struct drbd_resource, kref); 2283 2284 idr_destroy(&resource->devices); 2285 free_cpumask_var(resource->cpu_mask); 2286 kfree(resource->name); 2287 kfree(resource); 2288} 2289 2290void drbd_free_resource(struct drbd_resource *resource) 2291{ 2292 struct drbd_connection *connection, *tmp; 2293 2294 for_each_connection_safe(connection, tmp, resource) { 2295 list_del(&connection->connections); 2296 drbd_debugfs_connection_cleanup(connection); 2297 kref_put(&connection->kref, drbd_destroy_connection); 2298 } 2299 drbd_debugfs_resource_cleanup(resource); 2300 kref_put(&resource->kref, drbd_destroy_resource); 2301} 2302 2303static void drbd_cleanup(void) 2304{ 2305 unsigned int i; 2306 struct drbd_device *device; 2307 struct drbd_resource *resource, *tmp; 2308 2309 /* first remove proc, 2310 * drbdsetup uses it's presence to detect 2311 * whether DRBD is loaded. 2312 * If we would get stuck in proc removal, 2313 * but have netlink already deregistered, 2314 * some drbdsetup commands may wait forever 2315 * for an answer. 2316 */ 2317 if (drbd_proc) 2318 remove_proc_entry("drbd", NULL); 2319 2320 if (retry.wq) 2321 destroy_workqueue(retry.wq); 2322 2323 drbd_genl_unregister(); 2324 2325 idr_for_each_entry(&drbd_devices, device, i) 2326 drbd_delete_device(device); 2327 2328 /* not _rcu since, no other updater anymore. Genl already unregistered */ 2329 for_each_resource_safe(resource, tmp, &drbd_resources) { 2330 list_del(&resource->resources); 2331 drbd_free_resource(resource); 2332 } 2333 2334 drbd_debugfs_cleanup(); 2335 2336 drbd_destroy_mempools(); 2337 unregister_blkdev(DRBD_MAJOR, "drbd"); 2338 2339 idr_destroy(&drbd_devices); 2340 2341 pr_info("module cleanup done.\n"); 2342} 2343 2344static void drbd_init_workqueue(struct drbd_work_queue* wq) 2345{ 2346 spin_lock_init(&wq->q_lock); 2347 INIT_LIST_HEAD(&wq->q); 2348 init_waitqueue_head(&wq->q_wait); 2349} 2350 2351struct completion_work { 2352 struct drbd_work w; 2353 struct completion done; 2354}; 2355 2356static int w_complete(struct drbd_work *w, int cancel) 2357{ 2358 struct completion_work *completion_work = 2359 container_of(w, struct completion_work, w); 2360 2361 complete(&completion_work->done); 2362 return 0; 2363} 2364 2365void drbd_flush_workqueue(struct drbd_work_queue *work_queue) 2366{ 2367 struct completion_work completion_work; 2368 2369 completion_work.w.cb = w_complete; 2370 init_completion(&completion_work.done); 2371 drbd_queue_work(work_queue, &completion_work.w); 2372 wait_for_completion(&completion_work.done); 2373} 2374 2375struct drbd_resource *drbd_find_resource(const char *name) 2376{ 2377 struct drbd_resource *resource; 2378 2379 if (!name || !name[0]) 2380 return NULL; 2381 2382 rcu_read_lock(); 2383 for_each_resource_rcu(resource, &drbd_resources) { 2384 if (!strcmp(resource->name, name)) { 2385 kref_get(&resource->kref); 2386 goto found; 2387 } 2388 } 2389 resource = NULL; 2390found: 2391 rcu_read_unlock(); 2392 return resource; 2393} 2394 2395struct drbd_connection *conn_get_by_addrs(void *my_addr, int my_addr_len, 2396 void *peer_addr, int peer_addr_len) 2397{ 2398 struct drbd_resource *resource; 2399 struct drbd_connection *connection; 2400 2401 rcu_read_lock(); 2402 for_each_resource_rcu(resource, &drbd_resources) { 2403 for_each_connection_rcu(connection, resource) { 2404 if (connection->my_addr_len == my_addr_len && 2405 connection->peer_addr_len == peer_addr_len && 2406 !memcmp(&connection->my_addr, my_addr, my_addr_len) && 2407 !memcmp(&connection->peer_addr, peer_addr, peer_addr_len)) { 2408 kref_get(&connection->kref); 2409 goto found; 2410 } 2411 } 2412 } 2413 connection = NULL; 2414found: 2415 rcu_read_unlock(); 2416 return connection; 2417} 2418 2419static int drbd_alloc_socket(struct drbd_socket *socket) 2420{ 2421 socket->rbuf = (void *) __get_free_page(GFP_KERNEL); 2422 if (!socket->rbuf) 2423 return -ENOMEM; 2424 socket->sbuf = (void *) __get_free_page(GFP_KERNEL); 2425 if (!socket->sbuf) 2426 return -ENOMEM; 2427 return 0; 2428} 2429 2430static void drbd_free_socket(struct drbd_socket *socket) 2431{ 2432 free_page((unsigned long) socket->sbuf); 2433 free_page((unsigned long) socket->rbuf); 2434} 2435 2436void conn_free_crypto(struct drbd_connection *connection) 2437{ 2438 drbd_free_sock(connection); 2439 2440 crypto_free_shash(connection->csums_tfm); 2441 crypto_free_shash(connection->verify_tfm); 2442 crypto_free_shash(connection->cram_hmac_tfm); 2443 crypto_free_shash(connection->integrity_tfm); 2444 crypto_free_shash(connection->peer_integrity_tfm); 2445 kfree(connection->int_dig_in); 2446 kfree(connection->int_dig_vv); 2447 2448 connection->csums_tfm = NULL; 2449 connection->verify_tfm = NULL; 2450 connection->cram_hmac_tfm = NULL; 2451 connection->integrity_tfm = NULL; 2452 connection->peer_integrity_tfm = NULL; 2453 connection->int_dig_in = NULL; 2454 connection->int_dig_vv = NULL; 2455} 2456 2457int set_resource_options(struct drbd_resource *resource, struct res_opts *res_opts) 2458{ 2459 struct drbd_connection *connection; 2460 cpumask_var_t new_cpu_mask; 2461 int err; 2462 2463 if (!zalloc_cpumask_var(&new_cpu_mask, GFP_KERNEL)) 2464 return -ENOMEM; 2465 2466 /* silently ignore cpu mask on UP kernel */ 2467 if (nr_cpu_ids > 1 && res_opts->cpu_mask[0] != 0) { 2468 err = bitmap_parse(res_opts->cpu_mask, DRBD_CPU_MASK_SIZE, 2469 cpumask_bits(new_cpu_mask), nr_cpu_ids); 2470 if (err == -EOVERFLOW) { 2471 /* So what. mask it out. */ 2472 cpumask_var_t tmp_cpu_mask; 2473 if (zalloc_cpumask_var(&tmp_cpu_mask, GFP_KERNEL)) { 2474 cpumask_setall(tmp_cpu_mask); 2475 cpumask_and(new_cpu_mask, new_cpu_mask, tmp_cpu_mask); 2476 drbd_warn(resource, "Overflow in bitmap_parse(%.12s%s), truncating to %u bits\n", 2477 res_opts->cpu_mask, 2478 strlen(res_opts->cpu_mask) > 12 ? "..." : "", 2479 nr_cpu_ids); 2480 free_cpumask_var(tmp_cpu_mask); 2481 err = 0; 2482 } 2483 } 2484 if (err) { 2485 drbd_warn(resource, "bitmap_parse() failed with %d\n", err); 2486 /* retcode = ERR_CPU_MASK_PARSE; */ 2487 goto fail; 2488 } 2489 } 2490 resource->res_opts = *res_opts; 2491 if (cpumask_empty(new_cpu_mask)) 2492 drbd_calc_cpu_mask(&new_cpu_mask); 2493 if (!cpumask_equal(resource->cpu_mask, new_cpu_mask)) { 2494 cpumask_copy(resource->cpu_mask, new_cpu_mask); 2495 for_each_connection_rcu(connection, resource) { 2496 connection->receiver.reset_cpu_mask = 1; 2497 connection->ack_receiver.reset_cpu_mask = 1; 2498 connection->worker.reset_cpu_mask = 1; 2499 } 2500 } 2501 err = 0; 2502 2503fail: 2504 free_cpumask_var(new_cpu_mask); 2505 return err; 2506 2507} 2508 2509struct drbd_resource *drbd_create_resource(const char *name) 2510{ 2511 struct drbd_resource *resource; 2512 2513 resource = kzalloc(sizeof(struct drbd_resource), GFP_KERNEL); 2514 if (!resource) 2515 goto fail; 2516 resource->name = kstrdup(name, GFP_KERNEL); 2517 if (!resource->name) 2518 goto fail_free_resource; 2519 if (!zalloc_cpumask_var(&resource->cpu_mask, GFP_KERNEL)) 2520 goto fail_free_name; 2521 kref_init(&resource->kref); 2522 idr_init(&resource->devices); 2523 INIT_LIST_HEAD(&resource->connections); 2524 resource->write_ordering = WO_BDEV_FLUSH; 2525 list_add_tail_rcu(&resource->resources, &drbd_resources); 2526 mutex_init(&resource->conf_update); 2527 mutex_init(&resource->adm_mutex); 2528 spin_lock_init(&resource->req_lock); 2529 drbd_debugfs_resource_add(resource); 2530 return resource; 2531 2532fail_free_name: 2533 kfree(resource->name); 2534fail_free_resource: 2535 kfree(resource); 2536fail: 2537 return NULL; 2538} 2539 2540/* caller must be under adm_mutex */ 2541struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts) 2542{ 2543 struct drbd_resource *resource; 2544 struct drbd_connection *connection; 2545 2546 connection = kzalloc(sizeof(struct drbd_connection), GFP_KERNEL); 2547 if (!connection) 2548 return NULL; 2549 2550 if (drbd_alloc_socket(&connection->data)) 2551 goto fail; 2552 if (drbd_alloc_socket(&connection->meta)) 2553 goto fail; 2554 2555 connection->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL); 2556 if (!connection->current_epoch) 2557 goto fail; 2558 2559 INIT_LIST_HEAD(&connection->transfer_log); 2560 2561 INIT_LIST_HEAD(&connection->current_epoch->list); 2562 connection->epochs = 1; 2563 spin_lock_init(&connection->epoch_lock); 2564 2565 connection->send.seen_any_write_yet = false; 2566 connection->send.current_epoch_nr = 0; 2567 connection->send.current_epoch_writes = 0; 2568 2569 resource = drbd_create_resource(name); 2570 if (!resource) 2571 goto fail; 2572 2573 connection->cstate = C_STANDALONE; 2574 mutex_init(&connection->cstate_mutex); 2575 init_waitqueue_head(&connection->ping_wait); 2576 idr_init(&connection->peer_devices); 2577 2578 drbd_init_workqueue(&connection->sender_work); 2579 mutex_init(&connection->data.mutex); 2580 mutex_init(&connection->meta.mutex); 2581 2582 drbd_thread_init(resource, &connection->receiver, drbd_receiver, "receiver"); 2583 connection->receiver.connection = connection; 2584 drbd_thread_init(resource, &connection->worker, drbd_worker, "worker"); 2585 connection->worker.connection = connection; 2586 drbd_thread_init(resource, &connection->ack_receiver, drbd_ack_receiver, "ack_recv"); 2587 connection->ack_receiver.connection = connection; 2588 2589 kref_init(&connection->kref); 2590 2591 connection->resource = resource; 2592 2593 if (set_resource_options(resource, res_opts)) 2594 goto fail_resource; 2595 2596 kref_get(&resource->kref); 2597 list_add_tail_rcu(&connection->connections, &resource->connections); 2598 drbd_debugfs_connection_add(connection); 2599 return connection; 2600 2601fail_resource: 2602 list_del(&resource->resources); 2603 drbd_free_resource(resource); 2604fail: 2605 kfree(connection->current_epoch); 2606 drbd_free_socket(&connection->meta); 2607 drbd_free_socket(&connection->data); 2608 kfree(connection); 2609 return NULL; 2610} 2611 2612void drbd_destroy_connection(struct kref *kref) 2613{ 2614 struct drbd_connection *connection = container_of(kref, struct drbd_connection, kref); 2615 struct drbd_resource *resource = connection->resource; 2616 2617 if (atomic_read(&connection->current_epoch->epoch_size) != 0) 2618 drbd_err(connection, "epoch_size:%d\n", atomic_read(&connection->current_epoch->epoch_size)); 2619 kfree(connection->current_epoch); 2620 2621 idr_destroy(&connection->peer_devices); 2622 2623 drbd_free_socket(&connection->meta); 2624 drbd_free_socket(&connection->data); 2625 kfree(connection->int_dig_in); 2626 kfree(connection->int_dig_vv); 2627 kfree(connection); 2628 kref_put(&resource->kref, drbd_destroy_resource); 2629} 2630 2631static int init_submitter(struct drbd_device *device) 2632{ 2633 /* opencoded create_singlethread_workqueue(), 2634 * to be able to say "drbd%d", ..., minor */ 2635 device->submit.wq = 2636 alloc_ordered_workqueue("drbd%u_submit", WQ_MEM_RECLAIM, device->minor); 2637 if (!device->submit.wq) 2638 return -ENOMEM; 2639 2640 INIT_WORK(&device->submit.worker, do_submit); 2641 INIT_LIST_HEAD(&device->submit.writes); 2642 return 0; 2643} 2644 2645enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsigned int minor) 2646{ 2647 struct drbd_resource *resource = adm_ctx->resource; 2648 struct drbd_connection *connection, *n; 2649 struct drbd_device *device; 2650 struct drbd_peer_device *peer_device, *tmp_peer_device; 2651 struct gendisk *disk; 2652 int id; 2653 int vnr = adm_ctx->volume; 2654 enum drbd_ret_code err = ERR_NOMEM; 2655 struct queue_limits lim = { 2656 /* 2657 * Setting the max_hw_sectors to an odd value of 8kibyte here. 2658 * This triggers a max_bio_size message upon first attach or 2659 * connect. 2660 */ 2661 .max_hw_sectors = DRBD_MAX_BIO_SIZE_SAFE >> 8, 2662 }; 2663 2664 device = minor_to_device(minor); 2665 if (device) 2666 return ERR_MINOR_OR_VOLUME_EXISTS; 2667 2668 /* GFP_KERNEL, we are outside of all write-out paths */ 2669 device = kzalloc(sizeof(struct drbd_device), GFP_KERNEL); 2670 if (!device) 2671 return ERR_NOMEM; 2672 kref_init(&device->kref); 2673 2674 kref_get(&resource->kref); 2675 device->resource = resource; 2676 device->minor = minor; 2677 device->vnr = vnr; 2678 2679 drbd_init_set_defaults(device); 2680 2681 disk = blk_alloc_disk(&lim, NUMA_NO_NODE); 2682 if (IS_ERR(disk)) { 2683 err = PTR_ERR(disk); 2684 goto out_no_disk; 2685 } 2686 2687 device->vdisk = disk; 2688 device->rq_queue = disk->queue; 2689 2690 set_disk_ro(disk, true); 2691 2692 disk->major = DRBD_MAJOR; 2693 disk->first_minor = minor; 2694 disk->minors = 1; 2695 disk->fops = &drbd_ops; 2696 disk->flags |= GENHD_FL_NO_PART; 2697 sprintf(disk->disk_name, "drbd%d", minor); 2698 disk->private_data = device; 2699 2700 device->md_io.page = alloc_page(GFP_KERNEL); 2701 if (!device->md_io.page) 2702 goto out_no_io_page; 2703 2704 if (drbd_bm_init(device)) 2705 goto out_no_bitmap; 2706 device->read_requests = RB_ROOT; 2707 device->write_requests = RB_ROOT; 2708 2709 id = idr_alloc(&drbd_devices, device, minor, minor + 1, GFP_KERNEL); 2710 if (id < 0) { 2711 if (id == -ENOSPC) 2712 err = ERR_MINOR_OR_VOLUME_EXISTS; 2713 goto out_no_minor_idr; 2714 } 2715 kref_get(&device->kref); 2716 2717 id = idr_alloc(&resource->devices, device, vnr, vnr + 1, GFP_KERNEL); 2718 if (id < 0) { 2719 if (id == -ENOSPC) 2720 err = ERR_MINOR_OR_VOLUME_EXISTS; 2721 goto out_idr_remove_minor; 2722 } 2723 kref_get(&device->kref); 2724 2725 INIT_LIST_HEAD(&device->peer_devices); 2726 INIT_LIST_HEAD(&device->pending_bitmap_io); 2727 for_each_connection(connection, resource) { 2728 peer_device = kzalloc(sizeof(struct drbd_peer_device), GFP_KERNEL); 2729 if (!peer_device) 2730 goto out_idr_remove_from_resource; 2731 peer_device->connection = connection; 2732 peer_device->device = device; 2733 2734 list_add(&peer_device->peer_devices, &device->peer_devices); 2735 kref_get(&device->kref); 2736 2737 id = idr_alloc(&connection->peer_devices, peer_device, vnr, vnr + 1, GFP_KERNEL); 2738 if (id < 0) { 2739 if (id == -ENOSPC) 2740 err = ERR_INVALID_REQUEST; 2741 goto out_idr_remove_from_resource; 2742 } 2743 kref_get(&connection->kref); 2744 INIT_WORK(&peer_device->send_acks_work, drbd_send_acks_wf); 2745 } 2746 2747 if (init_submitter(device)) { 2748 err = ERR_NOMEM; 2749 goto out_idr_remove_from_resource; 2750 } 2751 2752 err = add_disk(disk); 2753 if (err) 2754 goto out_destroy_workqueue; 2755 2756 /* inherit the connection state */ 2757 device->state.conn = first_connection(resource)->cstate; 2758 if (device->state.conn == C_WF_REPORT_PARAMS) { 2759 for_each_peer_device(peer_device, device) 2760 drbd_connected(peer_device); 2761 } 2762 /* move to create_peer_device() */ 2763 for_each_peer_device(peer_device, device) 2764 drbd_debugfs_peer_device_add(peer_device); 2765 drbd_debugfs_device_add(device); 2766 return NO_ERROR; 2767 2768out_destroy_workqueue: 2769 destroy_workqueue(device->submit.wq); 2770out_idr_remove_from_resource: 2771 for_each_connection_safe(connection, n, resource) { 2772 peer_device = idr_remove(&connection->peer_devices, vnr); 2773 if (peer_device) 2774 kref_put(&connection->kref, drbd_destroy_connection); 2775 } 2776 for_each_peer_device_safe(peer_device, tmp_peer_device, device) { 2777 list_del(&peer_device->peer_devices); 2778 kfree(peer_device); 2779 } 2780 idr_remove(&resource->devices, vnr); 2781out_idr_remove_minor: 2782 idr_remove(&drbd_devices, minor); 2783 synchronize_rcu(); 2784out_no_minor_idr: 2785 drbd_bm_cleanup(device); 2786out_no_bitmap: 2787 __free_page(device->md_io.page); 2788out_no_io_page: 2789 put_disk(disk); 2790out_no_disk: 2791 kref_put(&resource->kref, drbd_destroy_resource); 2792 kfree(device); 2793 return err; 2794} 2795 2796void drbd_delete_device(struct drbd_device *device) 2797{ 2798 struct drbd_resource *resource = device->resource; 2799 struct drbd_connection *connection; 2800 struct drbd_peer_device *peer_device; 2801 2802 /* move to free_peer_device() */ 2803 for_each_peer_device(peer_device, device) 2804 drbd_debugfs_peer_device_cleanup(peer_device); 2805 drbd_debugfs_device_cleanup(device); 2806 for_each_connection(connection, resource) { 2807 idr_remove(&connection->peer_devices, device->vnr); 2808 kref_put(&device->kref, drbd_destroy_device); 2809 } 2810 idr_remove(&resource->devices, device->vnr); 2811 kref_put(&device->kref, drbd_destroy_device); 2812 idr_remove(&drbd_devices, device_to_minor(device)); 2813 kref_put(&device->kref, drbd_destroy_device); 2814 del_gendisk(device->vdisk); 2815 synchronize_rcu(); 2816 kref_put(&device->kref, drbd_destroy_device); 2817} 2818 2819static int __init drbd_init(void) 2820{ 2821 int err; 2822 2823 if (drbd_minor_count < DRBD_MINOR_COUNT_MIN || drbd_minor_count > DRBD_MINOR_COUNT_MAX) { 2824 pr_err("invalid minor_count (%d)\n", drbd_minor_count); 2825#ifdef MODULE 2826 return -EINVAL; 2827#else 2828 drbd_minor_count = DRBD_MINOR_COUNT_DEF; 2829#endif 2830 } 2831 2832 err = register_blkdev(DRBD_MAJOR, "drbd"); 2833 if (err) { 2834 pr_err("unable to register block device major %d\n", 2835 DRBD_MAJOR); 2836 return err; 2837 } 2838 2839 drbd_proc = NULL; /* play safe for drbd_cleanup */ 2840 idr_init(&drbd_devices); 2841 2842 mutex_init(&resources_mutex); 2843 INIT_LIST_HEAD(&drbd_resources); 2844 2845 err = drbd_genl_register(); 2846 if (err) { 2847 pr_err("unable to register generic netlink family\n"); 2848 goto fail; 2849 } 2850 2851 err = drbd_create_mempools(); 2852 if (err) 2853 goto fail; 2854 2855 err = -ENOMEM; 2856 drbd_proc = proc_create_single("drbd", S_IFREG | 0444 , NULL, drbd_seq_show); 2857 if (!drbd_proc) { 2858 pr_err("unable to register proc file\n"); 2859 goto fail; 2860 } 2861 2862 retry.wq = create_singlethread_workqueue("drbd-reissue"); 2863 if (!retry.wq) { 2864 pr_err("unable to create retry workqueue\n"); 2865 goto fail; 2866 } 2867 INIT_WORK(&retry.worker, do_retry); 2868 spin_lock_init(&retry.lock); 2869 INIT_LIST_HEAD(&retry.writes); 2870 2871 drbd_debugfs_init(); 2872 2873 pr_info("initialized. " 2874 "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n", 2875 GENL_MAGIC_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX); 2876 pr_info("%s\n", drbd_buildtag()); 2877 pr_info("registered as block device major %d\n", DRBD_MAJOR); 2878 return 0; /* Success! */ 2879 2880fail: 2881 drbd_cleanup(); 2882 if (err == -ENOMEM) 2883 pr_err("ran out of memory\n"); 2884 else 2885 pr_err("initialization failure\n"); 2886 return err; 2887} 2888 2889static void drbd_free_one_sock(struct drbd_socket *ds) 2890{ 2891 struct socket *s; 2892 mutex_lock(&ds->mutex); 2893 s = ds->socket; 2894 ds->socket = NULL; 2895 mutex_unlock(&ds->mutex); 2896 if (s) { 2897 /* so debugfs does not need to mutex_lock() */ 2898 synchronize_rcu(); 2899 kernel_sock_shutdown(s, SHUT_RDWR); 2900 sock_release(s); 2901 } 2902} 2903 2904void drbd_free_sock(struct drbd_connection *connection) 2905{ 2906 if (connection->data.socket) 2907 drbd_free_one_sock(&connection->data); 2908 if (connection->meta.socket) 2909 drbd_free_one_sock(&connection->meta); 2910} 2911 2912/* meta data management */ 2913 2914void conn_md_sync(struct drbd_connection *connection) 2915{ 2916 struct drbd_peer_device *peer_device; 2917 int vnr; 2918 2919 rcu_read_lock(); 2920 idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { 2921 struct drbd_device *device = peer_device->device; 2922 2923 kref_get(&device->kref); 2924 rcu_read_unlock(); 2925 drbd_md_sync(device); 2926 kref_put(&device->kref, drbd_destroy_device); 2927 rcu_read_lock(); 2928 } 2929 rcu_read_unlock(); 2930} 2931 2932/* aligned 4kByte */ 2933struct meta_data_on_disk { 2934 u64 la_size_sect; /* last agreed size. */ 2935 u64 uuid[UI_SIZE]; /* UUIDs. */ 2936 u64 device_uuid; 2937 u64 reserved_u64_1; 2938 u32 flags; /* MDF */ 2939 u32 magic; 2940 u32 md_size_sect; 2941 u32 al_offset; /* offset to this block */ 2942 u32 al_nr_extents; /* important for restoring the AL (userspace) */ 2943 /* `-- act_log->nr_elements <-- ldev->dc.al_extents */ 2944 u32 bm_offset; /* offset to the bitmap, from here */ 2945 u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */ 2946 u32 la_peer_max_bio_size; /* last peer max_bio_size */ 2947 2948 /* see al_tr_number_to_on_disk_sector() */ 2949 u32 al_stripes; 2950 u32 al_stripe_size_4k; 2951 2952 u8 reserved_u8[4096 - (7*8 + 10*4)]; 2953} __packed; 2954 2955 2956 2957void drbd_md_write(struct drbd_device *device, void *b) 2958{ 2959 struct meta_data_on_disk *buffer = b; 2960 sector_t sector; 2961 int i; 2962 2963 memset(buffer, 0, sizeof(*buffer)); 2964 2965 buffer->la_size_sect = cpu_to_be64(get_capacity(device->vdisk)); 2966 for (i = UI_CURRENT; i < UI_SIZE; i++) 2967 buffer->uuid[i] = cpu_to_be64(device->ldev->md.uuid[i]); 2968 buffer->flags = cpu_to_be32(device->ldev->md.flags); 2969 buffer->magic = cpu_to_be32(DRBD_MD_MAGIC_84_UNCLEAN); 2970 2971 buffer->md_size_sect = cpu_to_be32(device->ldev->md.md_size_sect); 2972 buffer->al_offset = cpu_to_be32(device->ldev->md.al_offset); 2973 buffer->al_nr_extents = cpu_to_be32(device->act_log->nr_elements); 2974 buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE); 2975 buffer->device_uuid = cpu_to_be64(device->ldev->md.device_uuid); 2976 2977 buffer->bm_offset = cpu_to_be32(device->ldev->md.bm_offset); 2978 buffer->la_peer_max_bio_size = cpu_to_be32(device->peer_max_bio_size); 2979 2980 buffer->al_stripes = cpu_to_be32(device->ldev->md.al_stripes); 2981 buffer->al_stripe_size_4k = cpu_to_be32(device->ldev->md.al_stripe_size_4k); 2982 2983 D_ASSERT(device, drbd_md_ss(device->ldev) == device->ldev->md.md_offset); 2984 sector = device->ldev->md.md_offset; 2985 2986 if (drbd_md_sync_page_io(device, device->ldev, sector, REQ_OP_WRITE)) { 2987 /* this was a try anyways ... */ 2988 drbd_err(device, "meta data update failed!\n"); 2989 drbd_chk_io_error(device, 1, DRBD_META_IO_ERROR); 2990 } 2991} 2992 2993/** 2994 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set 2995 * @device: DRBD device. 2996 */ 2997void drbd_md_sync(struct drbd_device *device) 2998{ 2999 struct meta_data_on_disk *buffer; 3000 3001 /* Don't accidentally change the DRBD meta data layout. */ 3002 BUILD_BUG_ON(UI_SIZE != 4); 3003 BUILD_BUG_ON(sizeof(struct meta_data_on_disk) != 4096); 3004 3005 timer_delete(&device->md_sync_timer); 3006 /* timer may be rearmed by drbd_md_mark_dirty() now. */ 3007 if (!test_and_clear_bit(MD_DIRTY, &device->flags)) 3008 return; 3009 3010 /* We use here D_FAILED and not D_ATTACHING because we try to write 3011 * metadata even if we detach due to a disk failure! */ 3012 if (!get_ldev_if_state(device, D_FAILED)) 3013 return; 3014 3015 buffer = drbd_md_get_buffer(device, __func__); 3016 if (!buffer) 3017 goto out; 3018 3019 drbd_md_write(device, buffer); 3020 3021 /* Update device->ldev->md.la_size_sect, 3022 * since we updated it on metadata. */ 3023 device->ldev->md.la_size_sect = get_capacity(device->vdisk); 3024 3025 drbd_md_put_buffer(device); 3026out: 3027 put_ldev(device); 3028} 3029 3030static int check_activity_log_stripe_size(struct drbd_device *device, 3031 struct meta_data_on_disk *on_disk, 3032 struct drbd_md *in_core) 3033{ 3034 u32 al_stripes = be32_to_cpu(on_disk->al_stripes); 3035 u32 al_stripe_size_4k = be32_to_cpu(on_disk->al_stripe_size_4k); 3036 u64 al_size_4k; 3037 3038 /* both not set: default to old fixed size activity log */ 3039 if (al_stripes == 0 && al_stripe_size_4k == 0) { 3040 al_stripes = 1; 3041 al_stripe_size_4k = MD_32kB_SECT/8; 3042 } 3043 3044 /* some paranoia plausibility checks */ 3045 3046 /* we need both values to be set */ 3047 if (al_stripes == 0 || al_stripe_size_4k == 0) 3048 goto err; 3049 3050 al_size_4k = (u64)al_stripes * al_stripe_size_4k; 3051 3052 /* Upper limit of activity log area, to avoid potential overflow 3053 * problems in al_tr_number_to_on_disk_sector(). As right now, more 3054 * than 72 * 4k blocks total only increases the amount of history, 3055 * limiting this arbitrarily to 16 GB is not a real limitation ;-) */ 3056 if (al_size_4k > (16 * 1024 * 1024/4)) 3057 goto err; 3058 3059 /* Lower limit: we need at least 8 transaction slots (32kB) 3060 * to not break existing setups */ 3061 if (al_size_4k < MD_32kB_SECT/8) 3062 goto err; 3063 3064 in_core->al_stripe_size_4k = al_stripe_size_4k; 3065 in_core->al_stripes = al_stripes; 3066 in_core->al_size_4k = al_size_4k; 3067 3068 return 0; 3069err: 3070 drbd_err(device, "invalid activity log striping: al_stripes=%u, al_stripe_size_4k=%u\n", 3071 al_stripes, al_stripe_size_4k); 3072 return -EINVAL; 3073} 3074 3075static int check_offsets_and_sizes(struct drbd_device *device, struct drbd_backing_dev *bdev) 3076{ 3077 sector_t capacity = drbd_get_capacity(bdev->md_bdev); 3078 struct drbd_md *in_core = &bdev->md; 3079 s32 on_disk_al_sect; 3080 s32 on_disk_bm_sect; 3081 3082 /* The on-disk size of the activity log, calculated from offsets, and 3083 * the size of the activity log calculated from the stripe settings, 3084 * should match. 3085 * Though we could relax this a bit: it is ok, if the striped activity log 3086 * fits in the available on-disk activity log size. 3087 * Right now, that would break how resize is implemented. 3088 * TODO: make drbd_determine_dev_size() (and the drbdmeta tool) aware 3089 * of possible unused padding space in the on disk layout. */ 3090 if (in_core->al_offset < 0) { 3091 if (in_core->bm_offset > in_core->al_offset) 3092 goto err; 3093 on_disk_al_sect = -in_core->al_offset; 3094 on_disk_bm_sect = in_core->al_offset - in_core->bm_offset; 3095 } else { 3096 if (in_core->al_offset != MD_4kB_SECT) 3097 goto err; 3098 if (in_core->bm_offset < in_core->al_offset + in_core->al_size_4k * MD_4kB_SECT) 3099 goto err; 3100 3101 on_disk_al_sect = in_core->bm_offset - MD_4kB_SECT; 3102 on_disk_bm_sect = in_core->md_size_sect - in_core->bm_offset; 3103 } 3104 3105 /* old fixed size meta data is exactly that: fixed. */ 3106 if (in_core->meta_dev_idx >= 0) { 3107 if (in_core->md_size_sect != MD_128MB_SECT 3108 || in_core->al_offset != MD_4kB_SECT 3109 || in_core->bm_offset != MD_4kB_SECT + MD_32kB_SECT 3110 || in_core->al_stripes != 1 3111 || in_core->al_stripe_size_4k != MD_32kB_SECT/8) 3112 goto err; 3113 } 3114 3115 if (capacity < in_core->md_size_sect) 3116 goto err; 3117 if (capacity - in_core->md_size_sect < drbd_md_first_sector(bdev)) 3118 goto err; 3119 3120 /* should be aligned, and at least 32k */ 3121 if ((on_disk_al_sect & 7) || (on_disk_al_sect < MD_32kB_SECT)) 3122 goto err; 3123 3124 /* should fit (for now: exactly) into the available on-disk space; 3125 * overflow prevention is in check_activity_log_stripe_size() above. */ 3126 if (on_disk_al_sect != in_core->al_size_4k * MD_4kB_SECT) 3127 goto err; 3128 3129 /* again, should be aligned */ 3130 if (in_core->bm_offset & 7) 3131 goto err; 3132 3133 /* FIXME check for device grow with flex external meta data? */ 3134 3135 /* can the available bitmap space cover the last agreed device size? */ 3136 if (on_disk_bm_sect < (in_core->la_size_sect+7)/MD_4kB_SECT/8/512) 3137 goto err; 3138 3139 return 0; 3140 3141err: 3142 drbd_err(device, "meta data offsets don't make sense: idx=%d " 3143 "al_s=%u, al_sz4k=%u, al_offset=%d, bm_offset=%d, " 3144 "md_size_sect=%u, la_size=%llu, md_capacity=%llu\n", 3145 in_core->meta_dev_idx, 3146 in_core->al_stripes, in_core->al_stripe_size_4k, 3147 in_core->al_offset, in_core->bm_offset, in_core->md_size_sect, 3148 (unsigned long long)in_core->la_size_sect, 3149 (unsigned long long)capacity); 3150 3151 return -EINVAL; 3152} 3153 3154 3155/** 3156 * drbd_md_read() - Reads in the meta data super block 3157 * @device: DRBD device. 3158 * @bdev: Device from which the meta data should be read in. 3159 * 3160 * Return NO_ERROR on success, and an enum drbd_ret_code in case 3161 * something goes wrong. 3162 * 3163 * Called exactly once during drbd_adm_attach(), while still being D_DISKLESS, 3164 * even before @bdev is assigned to @device->ldev. 3165 */ 3166int drbd_md_read(struct drbd_device *device, struct drbd_backing_dev *bdev) 3167{ 3168 struct meta_data_on_disk *buffer; 3169 u32 magic, flags; 3170 int i, rv = NO_ERROR; 3171 3172 if (device->state.disk != D_DISKLESS) 3173 return ERR_DISK_CONFIGURED; 3174 3175 buffer = drbd_md_get_buffer(device, __func__); 3176 if (!buffer) 3177 return ERR_NOMEM; 3178 3179 /* First, figure out where our meta data superblock is located, 3180 * and read it. */ 3181 bdev->md.meta_dev_idx = bdev->disk_conf->meta_dev_idx; 3182 bdev->md.md_offset = drbd_md_ss(bdev); 3183 /* Even for (flexible or indexed) external meta data, 3184 * initially restrict us to the 4k superblock for now. 3185 * Affects the paranoia out-of-range access check in drbd_md_sync_page_io(). */ 3186 bdev->md.md_size_sect = 8; 3187 3188 if (drbd_md_sync_page_io(device, bdev, bdev->md.md_offset, 3189 REQ_OP_READ)) { 3190 /* NOTE: can't do normal error processing here as this is 3191 called BEFORE disk is attached */ 3192 drbd_err(device, "Error while reading metadata.\n"); 3193 rv = ERR_IO_MD_DISK; 3194 goto err; 3195 } 3196 3197 magic = be32_to_cpu(buffer->magic); 3198 flags = be32_to_cpu(buffer->flags); 3199 if (magic == DRBD_MD_MAGIC_84_UNCLEAN || 3200 (magic == DRBD_MD_MAGIC_08 && !(flags & MDF_AL_CLEAN))) { 3201 /* btw: that's Activity Log clean, not "all" clean. */ 3202 drbd_err(device, "Found unclean meta data. Did you \"drbdadm apply-al\"?\n"); 3203 rv = ERR_MD_UNCLEAN; 3204 goto err; 3205 } 3206 3207 rv = ERR_MD_INVALID; 3208 if (magic != DRBD_MD_MAGIC_08) { 3209 if (magic == DRBD_MD_MAGIC_07) 3210 drbd_err(device, "Found old (0.7) meta data magic. Did you \"drbdadm create-md\"?\n"); 3211 else 3212 drbd_err(device, "Meta data magic not found. Did you \"drbdadm create-md\"?\n"); 3213 goto err; 3214 } 3215 3216 if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) { 3217 drbd_err(device, "unexpected bm_bytes_per_bit: %u (expected %u)\n", 3218 be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE); 3219 goto err; 3220 } 3221 3222 3223 /* convert to in_core endian */ 3224 bdev->md.la_size_sect = be64_to_cpu(buffer->la_size_sect); 3225 for (i = UI_CURRENT; i < UI_SIZE; i++) 3226 bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]); 3227 bdev->md.flags = be32_to_cpu(buffer->flags); 3228 bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid); 3229 3230 bdev->md.md_size_sect = be32_to_cpu(buffer->md_size_sect); 3231 bdev->md.al_offset = be32_to_cpu(buffer->al_offset); 3232 bdev->md.bm_offset = be32_to_cpu(buffer->bm_offset); 3233 3234 if (check_activity_log_stripe_size(device, buffer, &bdev->md)) 3235 goto err; 3236 if (check_offsets_and_sizes(device, bdev)) 3237 goto err; 3238 3239 if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) { 3240 drbd_err(device, "unexpected bm_offset: %d (expected %d)\n", 3241 be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset); 3242 goto err; 3243 } 3244 if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) { 3245 drbd_err(device, "unexpected md_size: %u (expected %u)\n", 3246 be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect); 3247 goto err; 3248 } 3249 3250 rv = NO_ERROR; 3251 3252 spin_lock_irq(&device->resource->req_lock); 3253 if (device->state.conn < C_CONNECTED) { 3254 unsigned int peer; 3255 peer = be32_to_cpu(buffer->la_peer_max_bio_size); 3256 peer = max(peer, DRBD_MAX_BIO_SIZE_SAFE); 3257 device->peer_max_bio_size = peer; 3258 } 3259 spin_unlock_irq(&device->resource->req_lock); 3260 3261 err: 3262 drbd_md_put_buffer(device); 3263 3264 return rv; 3265} 3266 3267/** 3268 * drbd_md_mark_dirty() - Mark meta data super block as dirty 3269 * @device: DRBD device. 3270 * 3271 * Call this function if you change anything that should be written to 3272 * the meta-data super block. This function sets MD_DIRTY, and starts a 3273 * timer that ensures that within five seconds you have to call drbd_md_sync(). 3274 */ 3275void drbd_md_mark_dirty(struct drbd_device *device) 3276{ 3277 if (!test_and_set_bit(MD_DIRTY, &device->flags)) 3278 mod_timer(&device->md_sync_timer, jiffies + 5*HZ); 3279} 3280 3281void drbd_uuid_move_history(struct drbd_device *device) __must_hold(local) 3282{ 3283 int i; 3284 3285 for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++) 3286 device->ldev->md.uuid[i+1] = device->ldev->md.uuid[i]; 3287} 3288 3289void __drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local) 3290{ 3291 if (idx == UI_CURRENT) { 3292 if (device->state.role == R_PRIMARY) 3293 val |= 1; 3294 else 3295 val &= ~((u64)1); 3296 3297 drbd_set_ed_uuid(device, val); 3298 } 3299 3300 device->ldev->md.uuid[idx] = val; 3301 drbd_md_mark_dirty(device); 3302} 3303 3304void _drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local) 3305{ 3306 unsigned long flags; 3307 spin_lock_irqsave(&device->ldev->md.uuid_lock, flags); 3308 __drbd_uuid_set(device, idx, val); 3309 spin_unlock_irqrestore(&device->ldev->md.uuid_lock, flags); 3310} 3311 3312void drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local) 3313{ 3314 unsigned long flags; 3315 spin_lock_irqsave(&device->ldev->md.uuid_lock, flags); 3316 if (device->ldev->md.uuid[idx]) { 3317 drbd_uuid_move_history(device); 3318 device->ldev->md.uuid[UI_HISTORY_START] = device->ldev->md.uuid[idx]; 3319 } 3320 __drbd_uuid_set(device, idx, val); 3321 spin_unlock_irqrestore(&device->ldev->md.uuid_lock, flags); 3322} 3323 3324/** 3325 * drbd_uuid_new_current() - Creates a new current UUID 3326 * @device: DRBD device. 3327 * 3328 * Creates a new current UUID, and rotates the old current UUID into 3329 * the bitmap slot. Causes an incremental resync upon next connect. 3330 */ 3331void drbd_uuid_new_current(struct drbd_device *device) __must_hold(local) 3332{ 3333 u64 val; 3334 unsigned long long bm_uuid; 3335 3336 get_random_bytes(&val, sizeof(u64)); 3337 3338 spin_lock_irq(&device->ldev->md.uuid_lock); 3339 bm_uuid = device->ldev->md.uuid[UI_BITMAP]; 3340 3341 if (bm_uuid) 3342 drbd_warn(device, "bm UUID was already set: %llX\n", bm_uuid); 3343 3344 device->ldev->md.uuid[UI_BITMAP] = device->ldev->md.uuid[UI_CURRENT]; 3345 __drbd_uuid_set(device, UI_CURRENT, val); 3346 spin_unlock_irq(&device->ldev->md.uuid_lock); 3347 3348 drbd_print_uuids(device, "new current UUID"); 3349 /* get it to stable storage _now_ */ 3350 drbd_md_sync(device); 3351} 3352 3353void drbd_uuid_set_bm(struct drbd_device *device, u64 val) __must_hold(local) 3354{ 3355 unsigned long flags; 3356 spin_lock_irqsave(&device->ldev->md.uuid_lock, flags); 3357 if (device->ldev->md.uuid[UI_BITMAP] == 0 && val == 0) { 3358 spin_unlock_irqrestore(&device->ldev->md.uuid_lock, flags); 3359 return; 3360 } 3361 3362 if (val == 0) { 3363 drbd_uuid_move_history(device); 3364 device->ldev->md.uuid[UI_HISTORY_START] = device->ldev->md.uuid[UI_BITMAP]; 3365 device->ldev->md.uuid[UI_BITMAP] = 0; 3366 } else { 3367 unsigned long long bm_uuid = device->ldev->md.uuid[UI_BITMAP]; 3368 if (bm_uuid) 3369 drbd_warn(device, "bm UUID was already set: %llX\n", bm_uuid); 3370 3371 device->ldev->md.uuid[UI_BITMAP] = val & ~((u64)1); 3372 } 3373 spin_unlock_irqrestore(&device->ldev->md.uuid_lock, flags); 3374 3375 drbd_md_mark_dirty(device); 3376} 3377 3378/** 3379 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io() 3380 * @device: DRBD device. 3381 * @peer_device: Peer DRBD device. 3382 * 3383 * Sets all bits in the bitmap and writes the whole bitmap to stable storage. 3384 */ 3385int drbd_bmio_set_n_write(struct drbd_device *device, 3386 struct drbd_peer_device *peer_device) __must_hold(local) 3387 3388{ 3389 int rv = -EIO; 3390 3391 drbd_md_set_flag(device, MDF_FULL_SYNC); 3392 drbd_md_sync(device); 3393 drbd_bm_set_all(device); 3394 3395 rv = drbd_bm_write(device, peer_device); 3396 3397 if (!rv) { 3398 drbd_md_clear_flag(device, MDF_FULL_SYNC); 3399 drbd_md_sync(device); 3400 } 3401 3402 return rv; 3403} 3404 3405/** 3406 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io() 3407 * @device: DRBD device. 3408 * @peer_device: Peer DRBD device. 3409 * 3410 * Clears all bits in the bitmap and writes the whole bitmap to stable storage. 3411 */ 3412int drbd_bmio_clear_n_write(struct drbd_device *device, 3413 struct drbd_peer_device *peer_device) __must_hold(local) 3414 3415{ 3416 drbd_resume_al(device); 3417 drbd_bm_clear_all(device); 3418 return drbd_bm_write(device, peer_device); 3419} 3420 3421static int w_bitmap_io(struct drbd_work *w, int unused) 3422{ 3423 struct drbd_device *device = 3424 container_of(w, struct drbd_device, bm_io_work.w); 3425 struct bm_io_work *work = &device->bm_io_work; 3426 int rv = -EIO; 3427 3428 if (work->flags != BM_LOCKED_CHANGE_ALLOWED) { 3429 int cnt = atomic_read(&device->ap_bio_cnt); 3430 if (cnt) 3431 drbd_err(device, "FIXME: ap_bio_cnt %d, expected 0; queued for '%s'\n", 3432 cnt, work->why); 3433 } 3434 3435 if (get_ldev(device)) { 3436 drbd_bm_lock(device, work->why, work->flags); 3437 rv = work->io_fn(device, work->peer_device); 3438 drbd_bm_unlock(device); 3439 put_ldev(device); 3440 } 3441 3442 clear_bit_unlock(BITMAP_IO, &device->flags); 3443 wake_up(&device->misc_wait); 3444 3445 if (work->done) 3446 work->done(device, rv); 3447 3448 clear_bit(BITMAP_IO_QUEUED, &device->flags); 3449 work->why = NULL; 3450 work->flags = 0; 3451 3452 return 0; 3453} 3454 3455/** 3456 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap 3457 * @device: DRBD device. 3458 * @io_fn: IO callback to be called when bitmap IO is possible 3459 * @done: callback to be called after the bitmap IO was performed 3460 * @why: Descriptive text of the reason for doing the IO 3461 * @flags: Bitmap flags 3462 * @peer_device: Peer DRBD device. 3463 * 3464 * While IO on the bitmap happens we freeze application IO thus we ensure 3465 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be 3466 * called from worker context. It MUST NOT be used while a previous such 3467 * work is still pending! 3468 * 3469 * Its worker function encloses the call of io_fn() by get_ldev() and 3470 * put_ldev(). 3471 */ 3472void drbd_queue_bitmap_io(struct drbd_device *device, 3473 int (*io_fn)(struct drbd_device *, struct drbd_peer_device *), 3474 void (*done)(struct drbd_device *, int), 3475 char *why, enum bm_flag flags, 3476 struct drbd_peer_device *peer_device) 3477{ 3478 D_ASSERT(device, current == peer_device->connection->worker.task); 3479 3480 D_ASSERT(device, !test_bit(BITMAP_IO_QUEUED, &device->flags)); 3481 D_ASSERT(device, !test_bit(BITMAP_IO, &device->flags)); 3482 D_ASSERT(device, list_empty(&device->bm_io_work.w.list)); 3483 if (device->bm_io_work.why) 3484 drbd_err(device, "FIXME going to queue '%s' but '%s' still pending?\n", 3485 why, device->bm_io_work.why); 3486 3487 device->bm_io_work.peer_device = peer_device; 3488 device->bm_io_work.io_fn = io_fn; 3489 device->bm_io_work.done = done; 3490 device->bm_io_work.why = why; 3491 device->bm_io_work.flags = flags; 3492 3493 spin_lock_irq(&device->resource->req_lock); 3494 set_bit(BITMAP_IO, &device->flags); 3495 /* don't wait for pending application IO if the caller indicates that 3496 * application IO does not conflict anyways. */ 3497 if (flags == BM_LOCKED_CHANGE_ALLOWED || atomic_read(&device->ap_bio_cnt) == 0) { 3498 if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags)) 3499 drbd_queue_work(&peer_device->connection->sender_work, 3500 &device->bm_io_work.w); 3501 } 3502 spin_unlock_irq(&device->resource->req_lock); 3503} 3504 3505/** 3506 * drbd_bitmap_io() - Does an IO operation on the whole bitmap 3507 * @device: DRBD device. 3508 * @io_fn: IO callback to be called when bitmap IO is possible 3509 * @why: Descriptive text of the reason for doing the IO 3510 * @flags: Bitmap flags 3511 * @peer_device: Peer DRBD device. 3512 * 3513 * freezes application IO while that the actual IO operations runs. This 3514 * functions MAY NOT be called from worker context. 3515 */ 3516int drbd_bitmap_io(struct drbd_device *device, 3517 int (*io_fn)(struct drbd_device *, struct drbd_peer_device *), 3518 char *why, enum bm_flag flags, 3519 struct drbd_peer_device *peer_device) 3520{ 3521 /* Only suspend io, if some operation is supposed to be locked out */ 3522 const bool do_suspend_io = flags & (BM_DONT_CLEAR|BM_DONT_SET|BM_DONT_TEST); 3523 int rv; 3524 3525 D_ASSERT(device, current != first_peer_device(device)->connection->worker.task); 3526 3527 if (do_suspend_io) 3528 drbd_suspend_io(device); 3529 3530 drbd_bm_lock(device, why, flags); 3531 rv = io_fn(device, peer_device); 3532 drbd_bm_unlock(device); 3533 3534 if (do_suspend_io) 3535 drbd_resume_io(device); 3536 3537 return rv; 3538} 3539 3540void drbd_md_set_flag(struct drbd_device *device, int flag) __must_hold(local) 3541{ 3542 if ((device->ldev->md.flags & flag) != flag) { 3543 drbd_md_mark_dirty(device); 3544 device->ldev->md.flags |= flag; 3545 } 3546} 3547 3548void drbd_md_clear_flag(struct drbd_device *device, int flag) __must_hold(local) 3549{ 3550 if ((device->ldev->md.flags & flag) != 0) { 3551 drbd_md_mark_dirty(device); 3552 device->ldev->md.flags &= ~flag; 3553 } 3554} 3555int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag) 3556{ 3557 return (bdev->md.flags & flag) != 0; 3558} 3559 3560static void md_sync_timer_fn(struct timer_list *t) 3561{ 3562 struct drbd_device *device = timer_container_of(device, t, 3563 md_sync_timer); 3564 drbd_device_post_work(device, MD_SYNC); 3565} 3566 3567const char *cmdname(enum drbd_packet cmd) 3568{ 3569 /* THINK may need to become several global tables 3570 * when we want to support more than 3571 * one PRO_VERSION */ 3572 static const char *cmdnames[] = { 3573 3574 [P_DATA] = "Data", 3575 [P_DATA_REPLY] = "DataReply", 3576 [P_RS_DATA_REPLY] = "RSDataReply", 3577 [P_BARRIER] = "Barrier", 3578 [P_BITMAP] = "ReportBitMap", 3579 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget", 3580 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource", 3581 [P_UNPLUG_REMOTE] = "UnplugRemote", 3582 [P_DATA_REQUEST] = "DataRequest", 3583 [P_RS_DATA_REQUEST] = "RSDataRequest", 3584 [P_SYNC_PARAM] = "SyncParam", 3585 [P_PROTOCOL] = "ReportProtocol", 3586 [P_UUIDS] = "ReportUUIDs", 3587 [P_SIZES] = "ReportSizes", 3588 [P_STATE] = "ReportState", 3589 [P_SYNC_UUID] = "ReportSyncUUID", 3590 [P_AUTH_CHALLENGE] = "AuthChallenge", 3591 [P_AUTH_RESPONSE] = "AuthResponse", 3592 [P_STATE_CHG_REQ] = "StateChgRequest", 3593 [P_PING] = "Ping", 3594 [P_PING_ACK] = "PingAck", 3595 [P_RECV_ACK] = "RecvAck", 3596 [P_WRITE_ACK] = "WriteAck", 3597 [P_RS_WRITE_ACK] = "RSWriteAck", 3598 [P_SUPERSEDED] = "Superseded", 3599 [P_NEG_ACK] = "NegAck", 3600 [P_NEG_DREPLY] = "NegDReply", 3601 [P_NEG_RS_DREPLY] = "NegRSDReply", 3602 [P_BARRIER_ACK] = "BarrierAck", 3603 [P_STATE_CHG_REPLY] = "StateChgReply", 3604 [P_OV_REQUEST] = "OVRequest", 3605 [P_OV_REPLY] = "OVReply", 3606 [P_OV_RESULT] = "OVResult", 3607 [P_CSUM_RS_REQUEST] = "CsumRSRequest", 3608 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync", 3609 [P_SYNC_PARAM89] = "SyncParam89", 3610 [P_COMPRESSED_BITMAP] = "CBitmap", 3611 [P_DELAY_PROBE] = "DelayProbe", 3612 [P_OUT_OF_SYNC] = "OutOfSync", 3613 [P_RS_CANCEL] = "RSCancel", 3614 [P_CONN_ST_CHG_REQ] = "conn_st_chg_req", 3615 [P_CONN_ST_CHG_REPLY] = "conn_st_chg_reply", 3616 [P_PROTOCOL_UPDATE] = "protocol_update", 3617 [P_TRIM] = "Trim", 3618 [P_RS_THIN_REQ] = "rs_thin_req", 3619 [P_RS_DEALLOCATED] = "rs_deallocated", 3620 [P_WSAME] = "WriteSame", 3621 [P_ZEROES] = "Zeroes", 3622 3623 /* enum drbd_packet, but not commands - obsoleted flags: 3624 * P_MAY_IGNORE 3625 * P_MAX_OPT_CMD 3626 */ 3627 }; 3628 3629 /* too big for the array: 0xfffX */ 3630 if (cmd == P_INITIAL_META) 3631 return "InitialMeta"; 3632 if (cmd == P_INITIAL_DATA) 3633 return "InitialData"; 3634 if (cmd == P_CONNECTION_FEATURES) 3635 return "ConnectionFeatures"; 3636 if (cmd >= ARRAY_SIZE(cmdnames)) 3637 return "Unknown"; 3638 return cmdnames[cmd]; 3639} 3640 3641/** 3642 * drbd_wait_misc - wait for a request to make progress 3643 * @device: device associated with the request 3644 * @i: the struct drbd_interval embedded in struct drbd_request or 3645 * struct drbd_peer_request 3646 */ 3647int drbd_wait_misc(struct drbd_device *device, struct drbd_interval *i) 3648{ 3649 struct net_conf *nc; 3650 DEFINE_WAIT(wait); 3651 long timeout; 3652 3653 rcu_read_lock(); 3654 nc = rcu_dereference(first_peer_device(device)->connection->net_conf); 3655 if (!nc) { 3656 rcu_read_unlock(); 3657 return -ETIMEDOUT; 3658 } 3659 timeout = nc->ko_count ? nc->timeout * HZ / 10 * nc->ko_count : MAX_SCHEDULE_TIMEOUT; 3660 rcu_read_unlock(); 3661 3662 /* Indicate to wake up device->misc_wait on progress. */ 3663 i->waiting = true; 3664 prepare_to_wait(&device->misc_wait, &wait, TASK_INTERRUPTIBLE); 3665 spin_unlock_irq(&device->resource->req_lock); 3666 timeout = schedule_timeout(timeout); 3667 finish_wait(&device->misc_wait, &wait); 3668 spin_lock_irq(&device->resource->req_lock); 3669 if (!timeout || device->state.conn < C_CONNECTED) 3670 return -ETIMEDOUT; 3671 if (signal_pending(current)) 3672 return -ERESTARTSYS; 3673 return 0; 3674} 3675 3676void lock_all_resources(void) 3677{ 3678 struct drbd_resource *resource; 3679 int __maybe_unused i = 0; 3680 3681 mutex_lock(&resources_mutex); 3682 local_irq_disable(); 3683 for_each_resource(resource, &drbd_resources) 3684 spin_lock_nested(&resource->req_lock, i++); 3685} 3686 3687void unlock_all_resources(void) 3688{ 3689 struct drbd_resource *resource; 3690 3691 for_each_resource(resource, &drbd_resources) 3692 spin_unlock(&resource->req_lock); 3693 local_irq_enable(); 3694 mutex_unlock(&resources_mutex); 3695} 3696 3697#ifdef CONFIG_DRBD_FAULT_INJECTION 3698/* Fault insertion support including random number generator shamelessly 3699 * stolen from kernel/rcutorture.c */ 3700struct fault_random_state { 3701 unsigned long state; 3702 unsigned long count; 3703}; 3704 3705#define FAULT_RANDOM_MULT 39916801 /* prime */ 3706#define FAULT_RANDOM_ADD 479001701 /* prime */ 3707#define FAULT_RANDOM_REFRESH 10000 3708 3709/* 3710 * Crude but fast random-number generator. Uses a linear congruential 3711 * generator, with occasional help from get_random_bytes(). 3712 */ 3713static unsigned long 3714_drbd_fault_random(struct fault_random_state *rsp) 3715{ 3716 long refresh; 3717 3718 if (!rsp->count--) { 3719 get_random_bytes(&refresh, sizeof(refresh)); 3720 rsp->state += refresh; 3721 rsp->count = FAULT_RANDOM_REFRESH; 3722 } 3723 rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD; 3724 return swahw32(rsp->state); 3725} 3726 3727static char * 3728_drbd_fault_str(unsigned int type) { 3729 static char *_faults[] = { 3730 [DRBD_FAULT_MD_WR] = "Meta-data write", 3731 [DRBD_FAULT_MD_RD] = "Meta-data read", 3732 [DRBD_FAULT_RS_WR] = "Resync write", 3733 [DRBD_FAULT_RS_RD] = "Resync read", 3734 [DRBD_FAULT_DT_WR] = "Data write", 3735 [DRBD_FAULT_DT_RD] = "Data read", 3736 [DRBD_FAULT_DT_RA] = "Data read ahead", 3737 [DRBD_FAULT_BM_ALLOC] = "BM allocation", 3738 [DRBD_FAULT_AL_EE] = "EE allocation", 3739 [DRBD_FAULT_RECEIVE] = "receive data corruption", 3740 }; 3741 3742 return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**"; 3743} 3744 3745unsigned int 3746_drbd_insert_fault(struct drbd_device *device, unsigned int type) 3747{ 3748 static struct fault_random_state rrs = {0, 0}; 3749 3750 unsigned int ret = ( 3751 (drbd_fault_devs == 0 || 3752 ((1 << device_to_minor(device)) & drbd_fault_devs) != 0) && 3753 (((_drbd_fault_random(&rrs) % 100) + 1) <= drbd_fault_rate)); 3754 3755 if (ret) { 3756 drbd_fault_count++; 3757 3758 if (drbd_ratelimit()) 3759 drbd_warn(device, "***Simulating %s failure\n", 3760 _drbd_fault_str(type)); 3761 } 3762 3763 return ret; 3764} 3765#endif 3766 3767module_init(drbd_init) 3768module_exit(drbd_cleanup) 3769 3770EXPORT_SYMBOL(drbd_conn_str); 3771EXPORT_SYMBOL(drbd_role_str); 3772EXPORT_SYMBOL(drbd_disk_str); 3773EXPORT_SYMBOL(drbd_set_st_err_str);
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