1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 drbd_int.h 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 12 */ 13 14 #ifndef _DRBD_INT_H 15 #define _DRBD_INT_H 16 17 #include <crypto/hash.h> 18 #include <linux/compiler.h> 19 #include <linux/types.h> 20 #include <linux/list.h> 21 #include <linux/sched/signal.h> 22 #include <linux/bitops.h> 23 #include <linux/slab.h> 24 #include <linux/ratelimit.h> 25 #include <linux/tcp.h> 26 #include <linux/mutex.h> 27 #include <linux/major.h> 28 #include <linux/blkdev.h> 29 #include <linux/backing-dev.h> 30 #include <linux/idr.h> 31 #include <linux/dynamic_debug.h> 32 #include <net/tcp.h> 33 #include <linux/lru_cache.h> 34 #include <linux/prefetch.h> 35 #include <linux/drbd_genl_api.h> 36 #include <linux/drbd.h> 37 #include "drbd_strings.h" 38 #include "drbd_state.h" 39 #include "drbd_protocol.h" 40 #include "drbd_polymorph_printk.h" 41 42 #ifdef __CHECKER__ 43 # define __protected_by(x) __attribute__((require_context(x,1,999,"rdwr"))) 44 # define __protected_read_by(x) __attribute__((require_context(x,1,999,"read"))) 45 # define __protected_write_by(x) __attribute__((require_context(x,1,999,"write"))) 46 #else 47 # define __protected_by(x) 48 # define __protected_read_by(x) 49 # define __protected_write_by(x) 50 #endif 51 52 /* shared module parameters, defined in drbd_main.c */ 53 #ifdef CONFIG_DRBD_FAULT_INJECTION 54 extern int drbd_enable_faults; 55 extern int drbd_fault_rate; 56 #endif 57 58 extern unsigned int drbd_minor_count; 59 extern char drbd_usermode_helper[]; 60 extern int drbd_proc_details; 61 62 63 /* This is used to stop/restart our threads. 64 * Cannot use SIGTERM nor SIGKILL, since these 65 * are sent out by init on runlevel changes 66 * I choose SIGHUP for now. 67 */ 68 #define DRBD_SIGKILL SIGHUP 69 70 #define ID_IN_SYNC (4711ULL) 71 #define ID_OUT_OF_SYNC (4712ULL) 72 #define ID_SYNCER (-1ULL) 73 74 #define UUID_NEW_BM_OFFSET ((u64)0x0001000000000000ULL) 75 76 struct drbd_device; 77 struct drbd_connection; 78 79 /* Defines to control fault insertion */ 80 enum { 81 DRBD_FAULT_MD_WR = 0, /* meta data write */ 82 DRBD_FAULT_MD_RD = 1, /* read */ 83 DRBD_FAULT_RS_WR = 2, /* resync */ 84 DRBD_FAULT_RS_RD = 3, 85 DRBD_FAULT_DT_WR = 4, /* data */ 86 DRBD_FAULT_DT_RD = 5, 87 DRBD_FAULT_DT_RA = 6, /* data read ahead */ 88 DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */ 89 DRBD_FAULT_AL_EE = 8, /* alloc ee */ 90 DRBD_FAULT_RECEIVE = 9, /* Changes some bytes upon receiving a [rs]data block */ 91 92 DRBD_FAULT_MAX, 93 }; 94 95 extern unsigned int 96 _drbd_insert_fault(struct drbd_device *device, unsigned int type); 97 98 static inline int 99 drbd_insert_fault(struct drbd_device *device, unsigned int type) { 100 #ifdef CONFIG_DRBD_FAULT_INJECTION 101 return drbd_fault_rate && 102 (drbd_enable_faults & (1<<type)) && 103 _drbd_insert_fault(device, type); 104 #else 105 return 0; 106 #endif 107 } 108 109 /* integer division, round _UP_ to the next integer */ 110 #define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0)) 111 /* usual integer division */ 112 #define div_floor(A, B) ((A)/(B)) 113 114 extern struct ratelimit_state drbd_ratelimit_state; 115 extern struct idr drbd_devices; /* RCU, updates: genl_lock() */ 116 extern struct list_head drbd_resources; /* RCU, updates: genl_lock() */ 117 118 extern const char *cmdname(enum drbd_packet cmd); 119 120 /* for sending/receiving the bitmap, 121 * possibly in some encoding scheme */ 122 struct bm_xfer_ctx { 123 /* "const" 124 * stores total bits and long words 125 * of the bitmap, so we don't need to 126 * call the accessor functions over and again. */ 127 unsigned long bm_bits; 128 unsigned long bm_words; 129 /* during xfer, current position within the bitmap */ 130 unsigned long bit_offset; 131 unsigned long word_offset; 132 133 /* statistics; index: (h->command == P_BITMAP) */ 134 unsigned packets[2]; 135 unsigned bytes[2]; 136 }; 137 138 extern void INFO_bm_xfer_stats(struct drbd_device *device, 139 const char *direction, struct bm_xfer_ctx *c); 140 141 static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c) 142 { 143 /* word_offset counts "native long words" (32 or 64 bit), 144 * aligned at 64 bit. 145 * Encoded packet may end at an unaligned bit offset. 146 * In case a fallback clear text packet is transmitted in 147 * between, we adjust this offset back to the last 64bit 148 * aligned "native long word", which makes coding and decoding 149 * the plain text bitmap much more convenient. */ 150 #if BITS_PER_LONG == 64 151 c->word_offset = c->bit_offset >> 6; 152 #elif BITS_PER_LONG == 32 153 c->word_offset = c->bit_offset >> 5; 154 c->word_offset &= ~(1UL); 155 #else 156 # error "unsupported BITS_PER_LONG" 157 #endif 158 } 159 160 extern unsigned int drbd_header_size(struct drbd_connection *connection); 161 162 /**********************************************************************/ 163 enum drbd_thread_state { 164 NONE, 165 RUNNING, 166 EXITING, 167 RESTARTING 168 }; 169 170 struct drbd_thread { 171 spinlock_t t_lock; 172 struct task_struct *task; 173 struct completion stop; 174 enum drbd_thread_state t_state; 175 int (*function) (struct drbd_thread *); 176 struct drbd_resource *resource; 177 struct drbd_connection *connection; 178 int reset_cpu_mask; 179 const char *name; 180 }; 181 182 static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi) 183 { 184 /* THINK testing the t_state seems to be uncritical in all cases 185 * (but thread_{start,stop}), so we can read it *without* the lock. 186 * --lge */ 187 188 smp_rmb(); 189 return thi->t_state; 190 } 191 192 struct drbd_work { 193 struct list_head list; 194 int (*cb)(struct drbd_work *, int cancel); 195 }; 196 197 struct drbd_device_work { 198 struct drbd_work w; 199 struct drbd_device *device; 200 }; 201 202 #include "drbd_interval.h" 203 204 extern int drbd_wait_misc(struct drbd_device *, struct drbd_interval *); 205 206 extern void lock_all_resources(void); 207 extern void unlock_all_resources(void); 208 209 struct drbd_request { 210 struct drbd_work w; 211 struct drbd_device *device; 212 213 /* if local IO is not allowed, will be NULL. 214 * if local IO _is_ allowed, holds the locally submitted bio clone, 215 * or, after local IO completion, the ERR_PTR(error). 216 * see drbd_request_endio(). */ 217 struct bio *private_bio; 218 219 struct drbd_interval i; 220 221 /* epoch: used to check on "completion" whether this req was in 222 * the current epoch, and we therefore have to close it, 223 * causing a p_barrier packet to be send, starting a new epoch. 224 * 225 * This corresponds to "barrier" in struct p_barrier[_ack], 226 * and to "barrier_nr" in struct drbd_epoch (and various 227 * comments/function parameters/local variable names). 228 */ 229 unsigned int epoch; 230 231 struct list_head tl_requests; /* ring list in the transfer log */ 232 struct bio *master_bio; /* master bio pointer */ 233 234 /* see struct drbd_device */ 235 struct list_head req_pending_master_completion; 236 struct list_head req_pending_local; 237 238 /* for generic IO accounting */ 239 unsigned long start_jif; 240 241 /* for DRBD internal statistics */ 242 243 /* Minimal set of time stamps to determine if we wait for activity log 244 * transactions, local disk or peer. 32 bit "jiffies" are good enough, 245 * we don't expect a DRBD request to be stalled for several month. 246 */ 247 248 /* before actual request processing */ 249 unsigned long in_actlog_jif; 250 251 /* local disk */ 252 unsigned long pre_submit_jif; 253 254 /* per connection */ 255 unsigned long pre_send_jif; 256 unsigned long acked_jif; 257 unsigned long net_done_jif; 258 259 /* Possibly even more detail to track each phase: 260 * master_completion_jif 261 * how long did it take to complete the master bio 262 * (application visible latency) 263 * allocated_jif 264 * how long the master bio was blocked until we finally allocated 265 * a tracking struct 266 * in_actlog_jif 267 * how long did we wait for activity log transactions 268 * 269 * net_queued_jif 270 * when did we finally queue it for sending 271 * pre_send_jif 272 * when did we start sending it 273 * post_send_jif 274 * how long did we block in the network stack trying to send it 275 * acked_jif 276 * when did we receive (or fake, in protocol A) a remote ACK 277 * net_done_jif 278 * when did we receive final acknowledgement (P_BARRIER_ACK), 279 * or decide, e.g. on connection loss, that we do no longer expect 280 * anything from this peer for this request. 281 * 282 * pre_submit_jif 283 * post_sub_jif 284 * when did we start submiting to the lower level device, 285 * and how long did we block in that submit function 286 * local_completion_jif 287 * how long did it take the lower level device to complete this request 288 */ 289 290 291 /* once it hits 0, we may complete the master_bio */ 292 atomic_t completion_ref; 293 /* once it hits 0, we may destroy this drbd_request object */ 294 struct kref kref; 295 296 unsigned rq_state; /* see comments above _req_mod() */ 297 }; 298 299 struct drbd_epoch { 300 struct drbd_connection *connection; 301 struct list_head list; 302 unsigned int barrier_nr; 303 atomic_t epoch_size; /* increased on every request added. */ 304 atomic_t active; /* increased on every req. added, and dec on every finished. */ 305 unsigned long flags; 306 }; 307 308 /* Prototype declaration of function defined in drbd_receiver.c */ 309 int drbdd_init(struct drbd_thread *); 310 int drbd_asender(struct drbd_thread *); 311 312 /* drbd_epoch flag bits */ 313 enum { 314 DE_HAVE_BARRIER_NUMBER, 315 }; 316 317 enum epoch_event { 318 EV_PUT, 319 EV_GOT_BARRIER_NR, 320 EV_BECAME_LAST, 321 EV_CLEANUP = 32, /* used as flag */ 322 }; 323 324 struct digest_info { 325 int digest_size; 326 void *digest; 327 }; 328 329 struct drbd_peer_request { 330 struct drbd_work w; 331 struct drbd_peer_device *peer_device; 332 struct drbd_epoch *epoch; /* for writes */ 333 struct page *pages; 334 blk_opf_t opf; 335 atomic_t pending_bios; 336 struct drbd_interval i; 337 /* see comments on ee flag bits below */ 338 unsigned long flags; 339 unsigned long submit_jif; 340 union { 341 u64 block_id; 342 struct digest_info *digest; 343 }; 344 }; 345 346 /* Equivalent to bio_op and req_op. */ 347 #define peer_req_op(peer_req) \ 348 ((peer_req)->opf & REQ_OP_MASK) 349 350 /* ee flag bits. 351 * While corresponding bios are in flight, the only modification will be 352 * set_bit WAS_ERROR, which has to be atomic. 353 * If no bios are in flight yet, or all have been completed, 354 * non-atomic modification to ee->flags is ok. 355 */ 356 enum { 357 __EE_CALL_AL_COMPLETE_IO, 358 __EE_MAY_SET_IN_SYNC, 359 360 /* is this a TRIM aka REQ_OP_DISCARD? */ 361 __EE_TRIM, 362 /* explicit zero-out requested, or 363 * our lower level cannot handle trim, 364 * and we want to fall back to zeroout instead */ 365 __EE_ZEROOUT, 366 367 /* In case a barrier failed, 368 * we need to resubmit without the barrier flag. */ 369 __EE_RESUBMITTED, 370 371 /* we may have several bios per peer request. 372 * if any of those fail, we set this flag atomically 373 * from the endio callback */ 374 __EE_WAS_ERROR, 375 376 /* This ee has a pointer to a digest instead of a block id */ 377 __EE_HAS_DIGEST, 378 379 /* Conflicting local requests need to be restarted after this request */ 380 __EE_RESTART_REQUESTS, 381 382 /* The peer wants a write ACK for this (wire proto C) */ 383 __EE_SEND_WRITE_ACK, 384 385 /* Is set when net_conf had two_primaries set while creating this peer_req */ 386 __EE_IN_INTERVAL_TREE, 387 388 /* for debugfs: */ 389 /* has this been submitted, or does it still wait for something else? */ 390 __EE_SUBMITTED, 391 392 /* this is/was a write request */ 393 __EE_WRITE, 394 395 /* this is/was a write same request */ 396 __EE_WRITE_SAME, 397 398 /* this originates from application on peer 399 * (not some resync or verify or other DRBD internal request) */ 400 __EE_APPLICATION, 401 402 /* If it contains only 0 bytes, send back P_RS_DEALLOCATED */ 403 __EE_RS_THIN_REQ, 404 }; 405 #define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO) 406 #define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC) 407 #define EE_TRIM (1<<__EE_TRIM) 408 #define EE_ZEROOUT (1<<__EE_ZEROOUT) 409 #define EE_RESUBMITTED (1<<__EE_RESUBMITTED) 410 #define EE_WAS_ERROR (1<<__EE_WAS_ERROR) 411 #define EE_HAS_DIGEST (1<<__EE_HAS_DIGEST) 412 #define EE_RESTART_REQUESTS (1<<__EE_RESTART_REQUESTS) 413 #define EE_SEND_WRITE_ACK (1<<__EE_SEND_WRITE_ACK) 414 #define EE_IN_INTERVAL_TREE (1<<__EE_IN_INTERVAL_TREE) 415 #define EE_SUBMITTED (1<<__EE_SUBMITTED) 416 #define EE_WRITE (1<<__EE_WRITE) 417 #define EE_WRITE_SAME (1<<__EE_WRITE_SAME) 418 #define EE_APPLICATION (1<<__EE_APPLICATION) 419 #define EE_RS_THIN_REQ (1<<__EE_RS_THIN_REQ) 420 421 /* flag bits per device */ 422 enum { 423 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */ 424 MD_DIRTY, /* current uuids and flags not yet on disk */ 425 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */ 426 CL_ST_CHG_SUCCESS, 427 CL_ST_CHG_FAIL, 428 CRASHED_PRIMARY, /* This node was a crashed primary. 429 * Gets cleared when the state.conn 430 * goes into C_CONNECTED state. */ 431 CONSIDER_RESYNC, 432 433 MD_NO_FUA, /* Users wants us to not use FUA/FLUSH on meta data dev */ 434 435 BITMAP_IO, /* suspend application io; 436 once no more io in flight, start bitmap io */ 437 BITMAP_IO_QUEUED, /* Started bitmap IO */ 438 WAS_IO_ERROR, /* Local disk failed, returned IO error */ 439 WAS_READ_ERROR, /* Local disk READ failed (set additionally to the above) */ 440 FORCE_DETACH, /* Force-detach from local disk, aborting any pending local IO */ 441 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */ 442 RESIZE_PENDING, /* Size change detected locally, waiting for the response from 443 * the peer, if it changed there as well. */ 444 NEW_CUR_UUID, /* Create new current UUID when thawing IO */ 445 AL_SUSPENDED, /* Activity logging is currently suspended. */ 446 AHEAD_TO_SYNC_SOURCE, /* Ahead -> SyncSource queued */ 447 B_RS_H_DONE, /* Before resync handler done (already executed) */ 448 DISCARD_MY_DATA, /* discard_my_data flag per volume */ 449 READ_BALANCE_RR, 450 451 FLUSH_PENDING, /* if set, device->flush_jif is when we submitted that flush 452 * from drbd_flush_after_epoch() */ 453 454 /* cleared only after backing device related structures have been destroyed. */ 455 GOING_DISKLESS, /* Disk is being detached, because of io-error, or admin request. */ 456 457 /* to be used in drbd_device_post_work() */ 458 GO_DISKLESS, /* tell worker to schedule cleanup before detach */ 459 DESTROY_DISK, /* tell worker to close backing devices and destroy related structures. */ 460 MD_SYNC, /* tell worker to call drbd_md_sync() */ 461 RS_START, /* tell worker to start resync/OV */ 462 RS_PROGRESS, /* tell worker that resync made significant progress */ 463 RS_DONE, /* tell worker that resync is done */ 464 }; 465 466 struct drbd_bitmap; /* opaque for drbd_device */ 467 468 /* definition of bits in bm_flags to be used in drbd_bm_lock 469 * and drbd_bitmap_io and friends. */ 470 enum bm_flag { 471 /* currently locked for bulk operation */ 472 BM_LOCKED_MASK = 0xf, 473 474 /* in detail, that is: */ 475 BM_DONT_CLEAR = 0x1, 476 BM_DONT_SET = 0x2, 477 BM_DONT_TEST = 0x4, 478 479 /* so we can mark it locked for bulk operation, 480 * and still allow all non-bulk operations */ 481 BM_IS_LOCKED = 0x8, 482 483 /* (test bit, count bit) allowed (common case) */ 484 BM_LOCKED_TEST_ALLOWED = BM_DONT_CLEAR | BM_DONT_SET | BM_IS_LOCKED, 485 486 /* testing bits, as well as setting new bits allowed, but clearing bits 487 * would be unexpected. Used during bitmap receive. Setting new bits 488 * requires sending of "out-of-sync" information, though. */ 489 BM_LOCKED_SET_ALLOWED = BM_DONT_CLEAR | BM_IS_LOCKED, 490 491 /* for drbd_bm_write_copy_pages, everything is allowed, 492 * only concurrent bulk operations are locked out. */ 493 BM_LOCKED_CHANGE_ALLOWED = BM_IS_LOCKED, 494 }; 495 496 struct drbd_work_queue { 497 struct list_head q; 498 spinlock_t q_lock; /* to protect the list. */ 499 wait_queue_head_t q_wait; 500 }; 501 502 struct drbd_socket { 503 struct mutex mutex; 504 struct socket *socket; 505 /* this way we get our 506 * send/receive buffers off the stack */ 507 void *sbuf; 508 void *rbuf; 509 }; 510 511 struct drbd_md { 512 u64 md_offset; /* sector offset to 'super' block */ 513 514 u64 la_size_sect; /* last agreed size, unit sectors */ 515 spinlock_t uuid_lock; 516 u64 uuid[UI_SIZE]; 517 u64 device_uuid; 518 u32 flags; 519 u32 md_size_sect; 520 521 s32 al_offset; /* signed relative sector offset to activity log */ 522 s32 bm_offset; /* signed relative sector offset to bitmap */ 523 524 /* cached value of bdev->disk_conf->meta_dev_idx (see below) */ 525 s32 meta_dev_idx; 526 527 /* see al_tr_number_to_on_disk_sector() */ 528 u32 al_stripes; 529 u32 al_stripe_size_4k; 530 u32 al_size_4k; /* cached product of the above */ 531 }; 532 533 struct drbd_backing_dev { 534 struct block_device *backing_bdev; 535 struct block_device *md_bdev; 536 struct drbd_md md; 537 struct disk_conf *disk_conf; /* RCU, for updates: resource->conf_update */ 538 sector_t known_size; /* last known size of that backing device */ 539 }; 540 541 struct drbd_md_io { 542 struct page *page; 543 unsigned long start_jif; /* last call to drbd_md_get_buffer */ 544 unsigned long submit_jif; /* last _drbd_md_sync_page_io() submit */ 545 const char *current_use; 546 atomic_t in_use; 547 unsigned int done; 548 int error; 549 }; 550 551 struct bm_io_work { 552 struct drbd_work w; 553 char *why; 554 enum bm_flag flags; 555 int (*io_fn)(struct drbd_device *device); 556 void (*done)(struct drbd_device *device, int rv); 557 }; 558 559 struct fifo_buffer { 560 unsigned int head_index; 561 unsigned int size; 562 int total; /* sum of all values */ 563 int values[]; 564 }; 565 extern struct fifo_buffer *fifo_alloc(unsigned int fifo_size); 566 567 /* flag bits per connection */ 568 enum { 569 NET_CONGESTED, /* The data socket is congested */ 570 RESOLVE_CONFLICTS, /* Set on one node, cleared on the peer! */ 571 SEND_PING, 572 GOT_PING_ACK, /* set when we receive a ping_ack packet, ping_wait gets woken */ 573 CONN_WD_ST_CHG_REQ, /* A cluster wide state change on the connection is active */ 574 CONN_WD_ST_CHG_OKAY, 575 CONN_WD_ST_CHG_FAIL, 576 CONN_DRY_RUN, /* Expect disconnect after resync handshake. */ 577 CREATE_BARRIER, /* next P_DATA is preceded by a P_BARRIER */ 578 STATE_SENT, /* Do not change state/UUIDs while this is set */ 579 CALLBACK_PENDING, /* Whether we have a call_usermodehelper(, UMH_WAIT_PROC) 580 * pending, from drbd worker context. 581 */ 582 DISCONNECT_SENT, 583 584 DEVICE_WORK_PENDING, /* tell worker that some device has pending work */ 585 }; 586 587 enum which_state { NOW, OLD = NOW, NEW }; 588 589 struct drbd_resource { 590 char *name; 591 #ifdef CONFIG_DEBUG_FS 592 struct dentry *debugfs_res; 593 struct dentry *debugfs_res_volumes; 594 struct dentry *debugfs_res_connections; 595 struct dentry *debugfs_res_in_flight_summary; 596 #endif 597 struct kref kref; 598 struct idr devices; /* volume number to device mapping */ 599 struct list_head connections; 600 struct list_head resources; 601 struct res_opts res_opts; 602 struct mutex conf_update; /* mutex for ready-copy-update of net_conf and disk_conf */ 603 struct mutex adm_mutex; /* mutex to serialize administrative requests */ 604 spinlock_t req_lock; 605 606 unsigned susp:1; /* IO suspended by user */ 607 unsigned susp_nod:1; /* IO suspended because no data */ 608 unsigned susp_fen:1; /* IO suspended because fence peer handler runs */ 609 610 enum write_ordering_e write_ordering; 611 612 cpumask_var_t cpu_mask; 613 }; 614 615 struct drbd_thread_timing_details 616 { 617 unsigned long start_jif; 618 void *cb_addr; 619 const char *caller_fn; 620 unsigned int line; 621 unsigned int cb_nr; 622 }; 623 624 struct drbd_connection { 625 struct list_head connections; 626 struct drbd_resource *resource; 627 #ifdef CONFIG_DEBUG_FS 628 struct dentry *debugfs_conn; 629 struct dentry *debugfs_conn_callback_history; 630 struct dentry *debugfs_conn_oldest_requests; 631 #endif 632 struct kref kref; 633 struct idr peer_devices; /* volume number to peer device mapping */ 634 enum drbd_conns cstate; /* Only C_STANDALONE to C_WF_REPORT_PARAMS */ 635 struct mutex cstate_mutex; /* Protects graceful disconnects */ 636 unsigned int connect_cnt; /* Inc each time a connection is established */ 637 638 unsigned long flags; 639 struct net_conf *net_conf; /* content protected by rcu */ 640 wait_queue_head_t ping_wait; /* Woken upon reception of a ping, and a state change */ 641 642 struct sockaddr_storage my_addr; 643 int my_addr_len; 644 struct sockaddr_storage peer_addr; 645 int peer_addr_len; 646 647 struct drbd_socket data; /* data/barrier/cstate/parameter packets */ 648 struct drbd_socket meta; /* ping/ack (metadata) packets */ 649 int agreed_pro_version; /* actually used protocol version */ 650 u32 agreed_features; 651 unsigned long last_received; /* in jiffies, either socket */ 652 unsigned int ko_count; 653 654 struct list_head transfer_log; /* all requests not yet fully processed */ 655 656 struct crypto_shash *cram_hmac_tfm; 657 struct crypto_shash *integrity_tfm; /* checksums we compute, updates protected by connection->data->mutex */ 658 struct crypto_shash *peer_integrity_tfm; /* checksums we verify, only accessed from receiver thread */ 659 struct crypto_shash *csums_tfm; 660 struct crypto_shash *verify_tfm; 661 void *int_dig_in; 662 void *int_dig_vv; 663 664 /* receiver side */ 665 struct drbd_epoch *current_epoch; 666 spinlock_t epoch_lock; 667 unsigned int epochs; 668 atomic_t current_tle_nr; /* transfer log epoch number */ 669 unsigned current_tle_writes; /* writes seen within this tl epoch */ 670 671 unsigned long last_reconnect_jif; 672 /* empty member on older kernels without blk_start_plug() */ 673 struct blk_plug receiver_plug; 674 struct drbd_thread receiver; 675 struct drbd_thread worker; 676 struct drbd_thread ack_receiver; 677 struct workqueue_struct *ack_sender; 678 679 /* cached pointers, 680 * so we can look up the oldest pending requests more quickly. 681 * protected by resource->req_lock */ 682 struct drbd_request *req_next; /* DRBD 9: todo.req_next */ 683 struct drbd_request *req_ack_pending; 684 struct drbd_request *req_not_net_done; 685 686 /* sender side */ 687 struct drbd_work_queue sender_work; 688 689 #define DRBD_THREAD_DETAILS_HIST 16 690 unsigned int w_cb_nr; /* keeps counting up */ 691 unsigned int r_cb_nr; /* keeps counting up */ 692 struct drbd_thread_timing_details w_timing_details[DRBD_THREAD_DETAILS_HIST]; 693 struct drbd_thread_timing_details r_timing_details[DRBD_THREAD_DETAILS_HIST]; 694 695 struct { 696 unsigned long last_sent_barrier_jif; 697 698 /* whether this sender thread 699 * has processed a single write yet. */ 700 bool seen_any_write_yet; 701 702 /* Which barrier number to send with the next P_BARRIER */ 703 int current_epoch_nr; 704 705 /* how many write requests have been sent 706 * with req->epoch == current_epoch_nr. 707 * If none, no P_BARRIER will be sent. */ 708 unsigned current_epoch_writes; 709 } send; 710 }; 711 712 static inline bool has_net_conf(struct drbd_connection *connection) 713 { 714 bool has_net_conf; 715 716 rcu_read_lock(); 717 has_net_conf = rcu_dereference(connection->net_conf); 718 rcu_read_unlock(); 719 720 return has_net_conf; 721 } 722 723 void __update_timing_details( 724 struct drbd_thread_timing_details *tdp, 725 unsigned int *cb_nr, 726 void *cb, 727 const char *fn, const unsigned int line); 728 729 #define update_worker_timing_details(c, cb) \ 730 __update_timing_details(c->w_timing_details, &c->w_cb_nr, cb, __func__ , __LINE__ ) 731 #define update_receiver_timing_details(c, cb) \ 732 __update_timing_details(c->r_timing_details, &c->r_cb_nr, cb, __func__ , __LINE__ ) 733 734 struct submit_worker { 735 struct workqueue_struct *wq; 736 struct work_struct worker; 737 738 /* protected by ..->resource->req_lock */ 739 struct list_head writes; 740 }; 741 742 struct drbd_peer_device { 743 struct list_head peer_devices; 744 struct drbd_device *device; 745 struct drbd_connection *connection; 746 struct work_struct send_acks_work; 747 #ifdef CONFIG_DEBUG_FS 748 struct dentry *debugfs_peer_dev; 749 #endif 750 }; 751 752 struct drbd_device { 753 struct drbd_resource *resource; 754 struct list_head peer_devices; 755 struct list_head pending_bitmap_io; 756 757 unsigned long flush_jif; 758 #ifdef CONFIG_DEBUG_FS 759 struct dentry *debugfs_minor; 760 struct dentry *debugfs_vol; 761 struct dentry *debugfs_vol_oldest_requests; 762 struct dentry *debugfs_vol_act_log_extents; 763 struct dentry *debugfs_vol_resync_extents; 764 struct dentry *debugfs_vol_data_gen_id; 765 struct dentry *debugfs_vol_ed_gen_id; 766 #endif 767 768 unsigned int vnr; /* volume number within the connection */ 769 unsigned int minor; /* device minor number */ 770 771 struct kref kref; 772 773 /* things that are stored as / read from meta data on disk */ 774 unsigned long flags; 775 776 /* configured by drbdsetup */ 777 struct drbd_backing_dev *ldev __protected_by(local); 778 779 sector_t p_size; /* partner's disk size */ 780 struct request_queue *rq_queue; 781 struct gendisk *vdisk; 782 783 unsigned long last_reattach_jif; 784 struct drbd_work resync_work; 785 struct drbd_work unplug_work; 786 struct timer_list resync_timer; 787 struct timer_list md_sync_timer; 788 struct timer_list start_resync_timer; 789 struct timer_list request_timer; 790 791 /* Used after attach while negotiating new disk state. */ 792 union drbd_state new_state_tmp; 793 794 union drbd_dev_state state; 795 wait_queue_head_t misc_wait; 796 wait_queue_head_t state_wait; /* upon each state change. */ 797 unsigned int send_cnt; 798 unsigned int recv_cnt; 799 unsigned int read_cnt; 800 unsigned int writ_cnt; 801 unsigned int al_writ_cnt; 802 unsigned int bm_writ_cnt; 803 atomic_t ap_bio_cnt; /* Requests we need to complete */ 804 atomic_t ap_actlog_cnt; /* Requests waiting for activity log */ 805 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */ 806 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */ 807 atomic_t unacked_cnt; /* Need to send replies for */ 808 atomic_t local_cnt; /* Waiting for local completion */ 809 atomic_t suspend_cnt; 810 811 /* Interval tree of pending local requests */ 812 struct rb_root read_requests; 813 struct rb_root write_requests; 814 815 /* for statistics and timeouts */ 816 /* [0] read, [1] write */ 817 struct list_head pending_master_completion[2]; 818 struct list_head pending_completion[2]; 819 820 /* use checksums for *this* resync */ 821 bool use_csums; 822 /* blocks to resync in this run [unit BM_BLOCK_SIZE] */ 823 unsigned long rs_total; 824 /* number of resync blocks that failed in this run */ 825 unsigned long rs_failed; 826 /* Syncer's start time [unit jiffies] */ 827 unsigned long rs_start; 828 /* cumulated time in PausedSyncX state [unit jiffies] */ 829 unsigned long rs_paused; 830 /* skipped because csum was equal [unit BM_BLOCK_SIZE] */ 831 unsigned long rs_same_csum; 832 #define DRBD_SYNC_MARKS 8 833 #define DRBD_SYNC_MARK_STEP (3*HZ) 834 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */ 835 unsigned long rs_mark_left[DRBD_SYNC_MARKS]; 836 /* marks's time [unit jiffies] */ 837 unsigned long rs_mark_time[DRBD_SYNC_MARKS]; 838 /* current index into rs_mark_{left,time} */ 839 int rs_last_mark; 840 unsigned long rs_last_bcast; /* [unit jiffies] */ 841 842 /* where does the admin want us to start? (sector) */ 843 sector_t ov_start_sector; 844 sector_t ov_stop_sector; 845 /* where are we now? (sector) */ 846 sector_t ov_position; 847 /* Start sector of out of sync range (to merge printk reporting). */ 848 sector_t ov_last_oos_start; 849 /* size of out-of-sync range in sectors. */ 850 sector_t ov_last_oos_size; 851 unsigned long ov_left; /* in bits */ 852 853 struct drbd_bitmap *bitmap; 854 unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */ 855 856 /* Used to track operations of resync... */ 857 struct lru_cache *resync; 858 /* Number of locked elements in resync LRU */ 859 unsigned int resync_locked; 860 /* resync extent number waiting for application requests */ 861 unsigned int resync_wenr; 862 863 int open_cnt; 864 u64 *p_uuid; 865 866 struct list_head active_ee; /* IO in progress (P_DATA gets written to disk) */ 867 struct list_head sync_ee; /* IO in progress (P_RS_DATA_REPLY gets written to disk) */ 868 struct list_head done_ee; /* need to send P_WRITE_ACK */ 869 struct list_head read_ee; /* [RS]P_DATA_REQUEST being read */ 870 struct list_head net_ee; /* zero-copy network send in progress */ 871 872 int next_barrier_nr; 873 struct list_head resync_reads; 874 atomic_t pp_in_use; /* allocated from page pool */ 875 atomic_t pp_in_use_by_net; /* sendpage()d, still referenced by tcp */ 876 wait_queue_head_t ee_wait; 877 struct drbd_md_io md_io; 878 spinlock_t al_lock; 879 wait_queue_head_t al_wait; 880 struct lru_cache *act_log; /* activity log */ 881 unsigned int al_tr_number; 882 int al_tr_cycle; 883 wait_queue_head_t seq_wait; 884 atomic_t packet_seq; 885 unsigned int peer_seq; 886 spinlock_t peer_seq_lock; 887 unsigned long comm_bm_set; /* communicated number of set bits. */ 888 struct bm_io_work bm_io_work; 889 u64 ed_uuid; /* UUID of the exposed data */ 890 struct mutex own_state_mutex; 891 struct mutex *state_mutex; /* either own_state_mutex or first_peer_device(device)->connection->cstate_mutex */ 892 char congestion_reason; /* Why we where congested... */ 893 atomic_t rs_sect_in; /* for incoming resync data rate, SyncTarget */ 894 atomic_t rs_sect_ev; /* for submitted resync data rate, both */ 895 int rs_last_sect_ev; /* counter to compare with */ 896 int rs_last_events; /* counter of read or write "events" (unit sectors) 897 * on the lower level device when we last looked. */ 898 int c_sync_rate; /* current resync rate after syncer throttle magic */ 899 struct fifo_buffer *rs_plan_s; /* correction values of resync planer (RCU, connection->conn_update) */ 900 int rs_in_flight; /* resync sectors in flight (to proxy, in proxy and from proxy) */ 901 atomic_t ap_in_flight; /* App sectors in flight (waiting for ack) */ 902 unsigned int peer_max_bio_size; 903 unsigned int local_max_bio_size; 904 905 /* any requests that would block in drbd_make_request() 906 * are deferred to this single-threaded work queue */ 907 struct submit_worker submit; 908 }; 909 910 struct drbd_bm_aio_ctx { 911 struct drbd_device *device; 912 struct list_head list; /* on device->pending_bitmap_io */; 913 unsigned long start_jif; 914 atomic_t in_flight; 915 unsigned int done; 916 unsigned flags; 917 #define BM_AIO_COPY_PAGES 1 918 #define BM_AIO_WRITE_HINTED 2 919 #define BM_AIO_WRITE_ALL_PAGES 4 920 #define BM_AIO_READ 8 921 int error; 922 struct kref kref; 923 }; 924 925 struct drbd_config_context { 926 /* assigned from drbd_genlmsghdr */ 927 unsigned int minor; 928 /* assigned from request attributes, if present */ 929 unsigned int volume; 930 #define VOLUME_UNSPECIFIED (-1U) 931 /* pointer into the request skb, 932 * limited lifetime! */ 933 char *resource_name; 934 struct nlattr *my_addr; 935 struct nlattr *peer_addr; 936 937 /* reply buffer */ 938 struct sk_buff *reply_skb; 939 /* pointer into reply buffer */ 940 struct drbd_genlmsghdr *reply_dh; 941 /* resolved from attributes, if possible */ 942 struct drbd_device *device; 943 struct drbd_resource *resource; 944 struct drbd_connection *connection; 945 }; 946 947 static inline struct drbd_device *minor_to_device(unsigned int minor) 948 { 949 return (struct drbd_device *)idr_find(&drbd_devices, minor); 950 } 951 952 static inline struct drbd_peer_device *first_peer_device(struct drbd_device *device) 953 { 954 return list_first_entry_or_null(&device->peer_devices, struct drbd_peer_device, peer_devices); 955 } 956 957 static inline struct drbd_peer_device * 958 conn_peer_device(struct drbd_connection *connection, int volume_number) 959 { 960 return idr_find(&connection->peer_devices, volume_number); 961 } 962 963 #define for_each_resource(resource, _resources) \ 964 list_for_each_entry(resource, _resources, resources) 965 966 #define for_each_resource_rcu(resource, _resources) \ 967 list_for_each_entry_rcu(resource, _resources, resources) 968 969 #define for_each_resource_safe(resource, tmp, _resources) \ 970 list_for_each_entry_safe(resource, tmp, _resources, resources) 971 972 #define for_each_connection(connection, resource) \ 973 list_for_each_entry(connection, &resource->connections, connections) 974 975 #define for_each_connection_rcu(connection, resource) \ 976 list_for_each_entry_rcu(connection, &resource->connections, connections) 977 978 #define for_each_connection_safe(connection, tmp, resource) \ 979 list_for_each_entry_safe(connection, tmp, &resource->connections, connections) 980 981 #define for_each_peer_device(peer_device, device) \ 982 list_for_each_entry(peer_device, &device->peer_devices, peer_devices) 983 984 #define for_each_peer_device_rcu(peer_device, device) \ 985 list_for_each_entry_rcu(peer_device, &device->peer_devices, peer_devices) 986 987 #define for_each_peer_device_safe(peer_device, tmp, device) \ 988 list_for_each_entry_safe(peer_device, tmp, &device->peer_devices, peer_devices) 989 990 static inline unsigned int device_to_minor(struct drbd_device *device) 991 { 992 return device->minor; 993 } 994 995 /* 996 * function declarations 997 *************************/ 998 999 /* drbd_main.c */ 1000 1001 enum dds_flags { 1002 DDSF_FORCED = 1, 1003 DDSF_NO_RESYNC = 2, /* Do not run a resync for the new space */ 1004 }; 1005 1006 extern void drbd_init_set_defaults(struct drbd_device *device); 1007 extern int drbd_thread_start(struct drbd_thread *thi); 1008 extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait); 1009 #ifdef CONFIG_SMP 1010 extern void drbd_thread_current_set_cpu(struct drbd_thread *thi); 1011 #else 1012 #define drbd_thread_current_set_cpu(A) ({}) 1013 #endif 1014 extern void tl_release(struct drbd_connection *, unsigned int barrier_nr, 1015 unsigned int set_size); 1016 extern void tl_clear(struct drbd_connection *); 1017 extern void drbd_free_sock(struct drbd_connection *connection); 1018 extern int drbd_send(struct drbd_connection *connection, struct socket *sock, 1019 void *buf, size_t size, unsigned msg_flags); 1020 extern int drbd_send_all(struct drbd_connection *, struct socket *, void *, size_t, 1021 unsigned); 1022 1023 extern int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cmd); 1024 extern int drbd_send_protocol(struct drbd_connection *connection); 1025 extern int drbd_send_uuids(struct drbd_peer_device *); 1026 extern int drbd_send_uuids_skip_initial_sync(struct drbd_peer_device *); 1027 extern void drbd_gen_and_send_sync_uuid(struct drbd_peer_device *); 1028 extern int drbd_send_sizes(struct drbd_peer_device *, int trigger_reply, enum dds_flags flags); 1029 extern int drbd_send_state(struct drbd_peer_device *, union drbd_state s); 1030 extern int drbd_send_current_state(struct drbd_peer_device *); 1031 extern int drbd_send_sync_param(struct drbd_peer_device *); 1032 extern void drbd_send_b_ack(struct drbd_connection *connection, u32 barrier_nr, 1033 u32 set_size); 1034 extern int drbd_send_ack(struct drbd_peer_device *, enum drbd_packet, 1035 struct drbd_peer_request *); 1036 extern void drbd_send_ack_rp(struct drbd_peer_device *, enum drbd_packet, 1037 struct p_block_req *rp); 1038 extern void drbd_send_ack_dp(struct drbd_peer_device *, enum drbd_packet, 1039 struct p_data *dp, int data_size); 1040 extern int drbd_send_ack_ex(struct drbd_peer_device *, enum drbd_packet, 1041 sector_t sector, int blksize, u64 block_id); 1042 extern int drbd_send_out_of_sync(struct drbd_peer_device *, struct drbd_request *); 1043 extern int drbd_send_block(struct drbd_peer_device *, enum drbd_packet, 1044 struct drbd_peer_request *); 1045 extern int drbd_send_dblock(struct drbd_peer_device *, struct drbd_request *req); 1046 extern int drbd_send_drequest(struct drbd_peer_device *, int cmd, 1047 sector_t sector, int size, u64 block_id); 1048 extern int drbd_send_drequest_csum(struct drbd_peer_device *, sector_t sector, 1049 int size, void *digest, int digest_size, 1050 enum drbd_packet cmd); 1051 extern int drbd_send_ov_request(struct drbd_peer_device *, sector_t sector, int size); 1052 1053 extern int drbd_send_bitmap(struct drbd_device *device); 1054 extern void drbd_send_sr_reply(struct drbd_peer_device *, enum drbd_state_rv retcode); 1055 extern void conn_send_sr_reply(struct drbd_connection *connection, enum drbd_state_rv retcode); 1056 extern int drbd_send_rs_deallocated(struct drbd_peer_device *, struct drbd_peer_request *); 1057 extern void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *ldev); 1058 extern void drbd_device_cleanup(struct drbd_device *device); 1059 extern void drbd_print_uuids(struct drbd_device *device, const char *text); 1060 extern void drbd_queue_unplug(struct drbd_device *device); 1061 1062 extern void conn_md_sync(struct drbd_connection *connection); 1063 extern void drbd_md_write(struct drbd_device *device, void *buffer); 1064 extern void drbd_md_sync(struct drbd_device *device); 1065 extern int drbd_md_read(struct drbd_device *device, struct drbd_backing_dev *bdev); 1066 extern void drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); 1067 extern void _drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); 1068 extern void drbd_uuid_new_current(struct drbd_device *device) __must_hold(local); 1069 extern void drbd_uuid_set_bm(struct drbd_device *device, u64 val) __must_hold(local); 1070 extern void drbd_uuid_move_history(struct drbd_device *device) __must_hold(local); 1071 extern void __drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); 1072 extern void drbd_md_set_flag(struct drbd_device *device, int flags) __must_hold(local); 1073 extern void drbd_md_clear_flag(struct drbd_device *device, int flags)__must_hold(local); 1074 extern int drbd_md_test_flag(struct drbd_backing_dev *, int); 1075 extern void drbd_md_mark_dirty(struct drbd_device *device); 1076 extern void drbd_queue_bitmap_io(struct drbd_device *device, 1077 int (*io_fn)(struct drbd_device *), 1078 void (*done)(struct drbd_device *, int), 1079 char *why, enum bm_flag flags); 1080 extern int drbd_bitmap_io(struct drbd_device *device, 1081 int (*io_fn)(struct drbd_device *), 1082 char *why, enum bm_flag flags); 1083 extern int drbd_bitmap_io_from_worker(struct drbd_device *device, 1084 int (*io_fn)(struct drbd_device *), 1085 char *why, enum bm_flag flags); 1086 extern int drbd_bmio_set_n_write(struct drbd_device *device) __must_hold(local); 1087 extern int drbd_bmio_clear_n_write(struct drbd_device *device) __must_hold(local); 1088 1089 /* Meta data layout 1090 * 1091 * We currently have two possible layouts. 1092 * Offsets in (512 byte) sectors. 1093 * external: 1094 * |----------- md_size_sect ------------------| 1095 * [ 4k superblock ][ activity log ][ Bitmap ] 1096 * | al_offset == 8 | 1097 * | bm_offset = al_offset + X | 1098 * ==> bitmap sectors = md_size_sect - bm_offset 1099 * 1100 * Variants: 1101 * old, indexed fixed size meta data: 1102 * 1103 * internal: 1104 * |----------- md_size_sect ------------------| 1105 * [data.....][ Bitmap ][ activity log ][ 4k superblock ][padding*] 1106 * | al_offset < 0 | 1107 * | bm_offset = al_offset - Y | 1108 * ==> bitmap sectors = Y = al_offset - bm_offset 1109 * 1110 * [padding*] are zero or up to 7 unused 512 Byte sectors to the 1111 * end of the device, so that the [4k superblock] will be 4k aligned. 1112 * 1113 * The activity log consists of 4k transaction blocks, 1114 * which are written in a ring-buffer, or striped ring-buffer like fashion, 1115 * which are writtensize used to be fixed 32kB, 1116 * but is about to become configurable. 1117 */ 1118 1119 /* Our old fixed size meta data layout 1120 * allows up to about 3.8TB, so if you want more, 1121 * you need to use the "flexible" meta data format. */ 1122 #define MD_128MB_SECT (128LLU << 11) /* 128 MB, unit sectors */ 1123 #define MD_4kB_SECT 8 1124 #define MD_32kB_SECT 64 1125 1126 /* One activity log extent represents 4M of storage */ 1127 #define AL_EXTENT_SHIFT 22 1128 #define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT) 1129 1130 /* We could make these currently hardcoded constants configurable 1131 * variables at create-md time (or even re-configurable at runtime?). 1132 * Which will require some more changes to the DRBD "super block" 1133 * and attach code. 1134 * 1135 * updates per transaction: 1136 * This many changes to the active set can be logged with one transaction. 1137 * This number is arbitrary. 1138 * context per transaction: 1139 * This many context extent numbers are logged with each transaction. 1140 * This number is resulting from the transaction block size (4k), the layout 1141 * of the transaction header, and the number of updates per transaction. 1142 * See drbd_actlog.c:struct al_transaction_on_disk 1143 * */ 1144 #define AL_UPDATES_PER_TRANSACTION 64 // arbitrary 1145 #define AL_CONTEXT_PER_TRANSACTION 919 // (4096 - 36 - 6*64)/4 1146 1147 #if BITS_PER_LONG == 32 1148 #define LN2_BPL 5 1149 #define cpu_to_lel(A) cpu_to_le32(A) 1150 #define lel_to_cpu(A) le32_to_cpu(A) 1151 #elif BITS_PER_LONG == 64 1152 #define LN2_BPL 6 1153 #define cpu_to_lel(A) cpu_to_le64(A) 1154 #define lel_to_cpu(A) le64_to_cpu(A) 1155 #else 1156 #error "LN2 of BITS_PER_LONG unknown!" 1157 #endif 1158 1159 /* resync bitmap */ 1160 /* 16MB sized 'bitmap extent' to track syncer usage */ 1161 struct bm_extent { 1162 int rs_left; /* number of bits set (out of sync) in this extent. */ 1163 int rs_failed; /* number of failed resync requests in this extent. */ 1164 unsigned long flags; 1165 struct lc_element lce; 1166 }; 1167 1168 #define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */ 1169 #define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */ 1170 #define BME_PRIORITY 2 /* finish resync IO on this extent ASAP! App IO waiting! */ 1171 1172 /* drbd_bitmap.c */ 1173 /* 1174 * We need to store one bit for a block. 1175 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap. 1176 * Bit 0 ==> local node thinks this block is binary identical on both nodes 1177 * Bit 1 ==> local node thinks this block needs to be synced. 1178 */ 1179 1180 #define SLEEP_TIME (HZ/10) 1181 1182 /* We do bitmap IO in units of 4k blocks. 1183 * We also still have a hardcoded 4k per bit relation. */ 1184 #define BM_BLOCK_SHIFT 12 /* 4k per bit */ 1185 #define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT) 1186 /* mostly arbitrarily set the represented size of one bitmap extent, 1187 * aka resync extent, to 16 MiB (which is also 512 Byte worth of bitmap 1188 * at 4k per bit resolution) */ 1189 #define BM_EXT_SHIFT 24 /* 16 MiB per resync extent */ 1190 #define BM_EXT_SIZE (1<<BM_EXT_SHIFT) 1191 1192 #if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12) 1193 #error "HAVE YOU FIXED drbdmeta AS WELL??" 1194 #endif 1195 1196 /* thus many _storage_ sectors are described by one bit */ 1197 #define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9)) 1198 #define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9)) 1199 #define BM_SECT_PER_BIT BM_BIT_TO_SECT(1) 1200 1201 /* bit to represented kilo byte conversion */ 1202 #define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10)) 1203 1204 /* in which _bitmap_ extent (resp. sector) the bit for a certain 1205 * _storage_ sector is located in */ 1206 #define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9)) 1207 #define BM_BIT_TO_EXT(x) ((x) >> (BM_EXT_SHIFT - BM_BLOCK_SHIFT)) 1208 1209 /* first storage sector a bitmap extent corresponds to */ 1210 #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9)) 1211 /* how much _storage_ sectors we have per bitmap extent */ 1212 #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1) 1213 /* how many bits are covered by one bitmap extent (resync extent) */ 1214 #define BM_BITS_PER_EXT (1UL << (BM_EXT_SHIFT - BM_BLOCK_SHIFT)) 1215 1216 #define BM_BLOCKS_PER_BM_EXT_MASK (BM_BITS_PER_EXT - 1) 1217 1218 1219 /* in one sector of the bitmap, we have this many activity_log extents. */ 1220 #define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT)) 1221 1222 /* the extent in "PER_EXTENT" below is an activity log extent 1223 * we need that many (long words/bytes) to store the bitmap 1224 * of one AL_EXTENT_SIZE chunk of storage. 1225 * we can store the bitmap for that many AL_EXTENTS within 1226 * one sector of the _on_disk_ bitmap: 1227 * bit 0 bit 37 bit 38 bit (512*8)-1 1228 * ...|........|........|.. // ..|........| 1229 * sect. 0 `296 `304 ^(512*8*8)-1 1230 * 1231 #define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG ) 1232 #define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128 1233 #define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4 1234 */ 1235 1236 #define DRBD_MAX_SECTORS_32 (0xffffffffLU) 1237 /* we have a certain meta data variant that has a fixed on-disk size of 128 1238 * MiB, of which 4k are our "superblock", and 32k are the fixed size activity 1239 * log, leaving this many sectors for the bitmap. 1240 */ 1241 1242 #define DRBD_MAX_SECTORS_FIXED_BM \ 1243 ((MD_128MB_SECT - MD_32kB_SECT - MD_4kB_SECT) * (1LL<<(BM_EXT_SHIFT-9))) 1244 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_FIXED_BM 1245 /* 16 TB in units of sectors */ 1246 #if BITS_PER_LONG == 32 1247 /* adjust by one page worth of bitmap, 1248 * so we won't wrap around in drbd_bm_find_next_bit. 1249 * you should use 64bit OS for that much storage, anyways. */ 1250 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff) 1251 #else 1252 /* we allow up to 1 PiB now on 64bit architecture with "flexible" meta data */ 1253 #define DRBD_MAX_SECTORS_FLEX (1UL << 51) 1254 /* corresponds to (1UL << 38) bits right now. */ 1255 #endif 1256 1257 /* Estimate max bio size as 256 * PAGE_SIZE, 1258 * so for typical PAGE_SIZE of 4k, that is (1<<20) Byte. 1259 * Since we may live in a mixed-platform cluster, 1260 * we limit us to a platform agnostic constant here for now. 1261 * A followup commit may allow even bigger BIO sizes, 1262 * once we thought that through. */ 1263 #define DRBD_MAX_BIO_SIZE (1U << 20) 1264 #if DRBD_MAX_BIO_SIZE > (BIO_MAX_VECS << PAGE_SHIFT) 1265 #error Architecture not supported: DRBD_MAX_BIO_SIZE > BIO_MAX_SIZE 1266 #endif 1267 #define DRBD_MAX_BIO_SIZE_SAFE (1U << 12) /* Works always = 4k */ 1268 1269 #define DRBD_MAX_SIZE_H80_PACKET (1U << 15) /* Header 80 only allows packets up to 32KiB data */ 1270 #define DRBD_MAX_BIO_SIZE_P95 (1U << 17) /* Protocol 95 to 99 allows bios up to 128KiB */ 1271 1272 /* For now, don't allow more than half of what we can "activate" in one 1273 * activity log transaction to be discarded in one go. We may need to rework 1274 * drbd_al_begin_io() to allow for even larger discard ranges */ 1275 #define DRBD_MAX_BATCH_BIO_SIZE (AL_UPDATES_PER_TRANSACTION/2*AL_EXTENT_SIZE) 1276 #define DRBD_MAX_BBIO_SECTORS (DRBD_MAX_BATCH_BIO_SIZE >> 9) 1277 1278 extern int drbd_bm_init(struct drbd_device *device); 1279 extern int drbd_bm_resize(struct drbd_device *device, sector_t sectors, int set_new_bits); 1280 extern void drbd_bm_cleanup(struct drbd_device *device); 1281 extern void drbd_bm_set_all(struct drbd_device *device); 1282 extern void drbd_bm_clear_all(struct drbd_device *device); 1283 /* set/clear/test only a few bits at a time */ 1284 extern int drbd_bm_set_bits( 1285 struct drbd_device *device, unsigned long s, unsigned long e); 1286 extern int drbd_bm_clear_bits( 1287 struct drbd_device *device, unsigned long s, unsigned long e); 1288 extern int drbd_bm_count_bits( 1289 struct drbd_device *device, const unsigned long s, const unsigned long e); 1290 /* bm_set_bits variant for use while holding drbd_bm_lock, 1291 * may process the whole bitmap in one go */ 1292 extern void _drbd_bm_set_bits(struct drbd_device *device, 1293 const unsigned long s, const unsigned long e); 1294 extern int drbd_bm_test_bit(struct drbd_device *device, unsigned long bitnr); 1295 extern int drbd_bm_e_weight(struct drbd_device *device, unsigned long enr); 1296 extern int drbd_bm_read(struct drbd_device *device) __must_hold(local); 1297 extern void drbd_bm_mark_for_writeout(struct drbd_device *device, int page_nr); 1298 extern int drbd_bm_write(struct drbd_device *device) __must_hold(local); 1299 extern void drbd_bm_reset_al_hints(struct drbd_device *device) __must_hold(local); 1300 extern int drbd_bm_write_hinted(struct drbd_device *device) __must_hold(local); 1301 extern int drbd_bm_write_lazy(struct drbd_device *device, unsigned upper_idx) __must_hold(local); 1302 extern int drbd_bm_write_all(struct drbd_device *device) __must_hold(local); 1303 extern int drbd_bm_write_copy_pages(struct drbd_device *device) __must_hold(local); 1304 extern size_t drbd_bm_words(struct drbd_device *device); 1305 extern unsigned long drbd_bm_bits(struct drbd_device *device); 1306 extern sector_t drbd_bm_capacity(struct drbd_device *device); 1307 1308 #define DRBD_END_OF_BITMAP (~(unsigned long)0) 1309 extern unsigned long drbd_bm_find_next(struct drbd_device *device, unsigned long bm_fo); 1310 /* bm_find_next variants for use while you hold drbd_bm_lock() */ 1311 extern unsigned long _drbd_bm_find_next(struct drbd_device *device, unsigned long bm_fo); 1312 extern unsigned long _drbd_bm_find_next_zero(struct drbd_device *device, unsigned long bm_fo); 1313 extern unsigned long _drbd_bm_total_weight(struct drbd_device *device); 1314 extern unsigned long drbd_bm_total_weight(struct drbd_device *device); 1315 /* for receive_bitmap */ 1316 extern void drbd_bm_merge_lel(struct drbd_device *device, size_t offset, 1317 size_t number, unsigned long *buffer); 1318 /* for _drbd_send_bitmap */ 1319 extern void drbd_bm_get_lel(struct drbd_device *device, size_t offset, 1320 size_t number, unsigned long *buffer); 1321 1322 extern void drbd_bm_lock(struct drbd_device *device, char *why, enum bm_flag flags); 1323 extern void drbd_bm_unlock(struct drbd_device *device); 1324 /* drbd_main.c */ 1325 1326 extern struct kmem_cache *drbd_request_cache; 1327 extern struct kmem_cache *drbd_ee_cache; /* peer requests */ 1328 extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 1329 extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 1330 extern mempool_t drbd_request_mempool; 1331 extern mempool_t drbd_ee_mempool; 1332 1333 /* drbd's page pool, used to buffer data received from the peer, 1334 * or data requested by the peer. 1335 * 1336 * This does not have an emergency reserve. 1337 * 1338 * When allocating from this pool, it first takes pages from the pool. 1339 * Only if the pool is depleted will try to allocate from the system. 1340 * 1341 * The assumption is that pages taken from this pool will be processed, 1342 * and given back, "quickly", and then can be recycled, so we can avoid 1343 * frequent calls to alloc_page(), and still will be able to make progress even 1344 * under memory pressure. 1345 */ 1346 extern struct page *drbd_pp_pool; 1347 extern spinlock_t drbd_pp_lock; 1348 extern int drbd_pp_vacant; 1349 extern wait_queue_head_t drbd_pp_wait; 1350 1351 /* We also need a standard (emergency-reserve backed) page pool 1352 * for meta data IO (activity log, bitmap). 1353 * We can keep it global, as long as it is used as "N pages at a time". 1354 * 128 should be plenty, currently we probably can get away with as few as 1. 1355 */ 1356 #define DRBD_MIN_POOL_PAGES 128 1357 extern mempool_t drbd_md_io_page_pool; 1358 1359 /* We also need to make sure we get a bio 1360 * when we need it for housekeeping purposes */ 1361 extern struct bio_set drbd_md_io_bio_set; 1362 1363 /* And a bio_set for cloning */ 1364 extern struct bio_set drbd_io_bio_set; 1365 1366 extern struct mutex resources_mutex; 1367 1368 extern int conn_lowest_minor(struct drbd_connection *connection); 1369 extern enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsigned int minor); 1370 extern void drbd_destroy_device(struct kref *kref); 1371 extern void drbd_delete_device(struct drbd_device *device); 1372 1373 extern struct drbd_resource *drbd_create_resource(const char *name); 1374 extern void drbd_free_resource(struct drbd_resource *resource); 1375 1376 extern int set_resource_options(struct drbd_resource *resource, struct res_opts *res_opts); 1377 extern struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts); 1378 extern void drbd_destroy_connection(struct kref *kref); 1379 extern struct drbd_connection *conn_get_by_addrs(void *my_addr, int my_addr_len, 1380 void *peer_addr, int peer_addr_len); 1381 extern struct drbd_resource *drbd_find_resource(const char *name); 1382 extern void drbd_destroy_resource(struct kref *kref); 1383 extern void conn_free_crypto(struct drbd_connection *connection); 1384 1385 /* drbd_req */ 1386 extern void do_submit(struct work_struct *ws); 1387 extern void __drbd_make_request(struct drbd_device *, struct bio *); 1388 void drbd_submit_bio(struct bio *bio); 1389 extern int drbd_read_remote(struct drbd_device *device, struct drbd_request *req); 1390 extern int is_valid_ar_handle(struct drbd_request *, sector_t); 1391 1392 1393 /* drbd_nl.c */ 1394 1395 extern struct mutex notification_mutex; 1396 1397 extern void drbd_suspend_io(struct drbd_device *device); 1398 extern void drbd_resume_io(struct drbd_device *device); 1399 extern char *ppsize(char *buf, unsigned long long size); 1400 extern sector_t drbd_new_dev_size(struct drbd_device *, struct drbd_backing_dev *, sector_t, int); 1401 enum determine_dev_size { 1402 DS_ERROR_SHRINK = -3, 1403 DS_ERROR_SPACE_MD = -2, 1404 DS_ERROR = -1, 1405 DS_UNCHANGED = 0, 1406 DS_SHRUNK = 1, 1407 DS_GREW = 2, 1408 DS_GREW_FROM_ZERO = 3, 1409 }; 1410 extern enum determine_dev_size 1411 drbd_determine_dev_size(struct drbd_device *, enum dds_flags, struct resize_parms *) __must_hold(local); 1412 extern void resync_after_online_grow(struct drbd_device *); 1413 extern void drbd_reconsider_queue_parameters(struct drbd_device *device, 1414 struct drbd_backing_dev *bdev, struct o_qlim *o); 1415 extern enum drbd_state_rv drbd_set_role(struct drbd_device *device, 1416 enum drbd_role new_role, 1417 int force); 1418 extern bool conn_try_outdate_peer(struct drbd_connection *connection); 1419 extern void conn_try_outdate_peer_async(struct drbd_connection *connection); 1420 extern enum drbd_peer_state conn_khelper(struct drbd_connection *connection, char *cmd); 1421 extern int drbd_khelper(struct drbd_device *device, char *cmd); 1422 1423 /* drbd_worker.c */ 1424 /* bi_end_io handlers */ 1425 extern void drbd_md_endio(struct bio *bio); 1426 extern void drbd_peer_request_endio(struct bio *bio); 1427 extern void drbd_request_endio(struct bio *bio); 1428 extern int drbd_worker(struct drbd_thread *thi); 1429 enum drbd_ret_code drbd_resync_after_valid(struct drbd_device *device, int o_minor); 1430 void drbd_resync_after_changed(struct drbd_device *device); 1431 extern void drbd_start_resync(struct drbd_device *device, enum drbd_conns side); 1432 extern void resume_next_sg(struct drbd_device *device); 1433 extern void suspend_other_sg(struct drbd_device *device); 1434 extern int drbd_resync_finished(struct drbd_device *device); 1435 /* maybe rather drbd_main.c ? */ 1436 extern void *drbd_md_get_buffer(struct drbd_device *device, const char *intent); 1437 extern void drbd_md_put_buffer(struct drbd_device *device); 1438 extern int drbd_md_sync_page_io(struct drbd_device *device, 1439 struct drbd_backing_dev *bdev, sector_t sector, enum req_op op); 1440 extern void drbd_ov_out_of_sync_found(struct drbd_device *, sector_t, int); 1441 extern void wait_until_done_or_force_detached(struct drbd_device *device, 1442 struct drbd_backing_dev *bdev, unsigned int *done); 1443 extern void drbd_rs_controller_reset(struct drbd_device *device); 1444 1445 static inline void ov_out_of_sync_print(struct drbd_device *device) 1446 { 1447 if (device->ov_last_oos_size) { 1448 drbd_err(device, "Out of sync: start=%llu, size=%lu (sectors)\n", 1449 (unsigned long long)device->ov_last_oos_start, 1450 (unsigned long)device->ov_last_oos_size); 1451 } 1452 device->ov_last_oos_size = 0; 1453 } 1454 1455 1456 extern void drbd_csum_bio(struct crypto_shash *, struct bio *, void *); 1457 extern void drbd_csum_ee(struct crypto_shash *, struct drbd_peer_request *, 1458 void *); 1459 /* worker callbacks */ 1460 extern int w_e_end_data_req(struct drbd_work *, int); 1461 extern int w_e_end_rsdata_req(struct drbd_work *, int); 1462 extern int w_e_end_csum_rs_req(struct drbd_work *, int); 1463 extern int w_e_end_ov_reply(struct drbd_work *, int); 1464 extern int w_e_end_ov_req(struct drbd_work *, int); 1465 extern int w_ov_finished(struct drbd_work *, int); 1466 extern int w_resync_timer(struct drbd_work *, int); 1467 extern int w_send_write_hint(struct drbd_work *, int); 1468 extern int w_send_dblock(struct drbd_work *, int); 1469 extern int w_send_read_req(struct drbd_work *, int); 1470 extern int w_e_reissue(struct drbd_work *, int); 1471 extern int w_restart_disk_io(struct drbd_work *, int); 1472 extern int w_send_out_of_sync(struct drbd_work *, int); 1473 1474 extern void resync_timer_fn(struct timer_list *t); 1475 extern void start_resync_timer_fn(struct timer_list *t); 1476 1477 extern void drbd_endio_write_sec_final(struct drbd_peer_request *peer_req); 1478 1479 /* drbd_receiver.c */ 1480 extern int drbd_issue_discard_or_zero_out(struct drbd_device *device, 1481 sector_t start, unsigned int nr_sectors, int flags); 1482 extern int drbd_receiver(struct drbd_thread *thi); 1483 extern int drbd_ack_receiver(struct drbd_thread *thi); 1484 extern void drbd_send_ping_wf(struct work_struct *ws); 1485 extern void drbd_send_acks_wf(struct work_struct *ws); 1486 extern bool drbd_rs_c_min_rate_throttle(struct drbd_device *device); 1487 extern bool drbd_rs_should_slow_down(struct drbd_device *device, sector_t sector, 1488 bool throttle_if_app_is_waiting); 1489 extern int drbd_submit_peer_request(struct drbd_peer_request *peer_req); 1490 extern int drbd_free_peer_reqs(struct drbd_device *, struct list_head *); 1491 extern struct drbd_peer_request *drbd_alloc_peer_req(struct drbd_peer_device *, u64, 1492 sector_t, unsigned int, 1493 unsigned int, 1494 gfp_t) __must_hold(local); 1495 extern void __drbd_free_peer_req(struct drbd_device *, struct drbd_peer_request *, 1496 int); 1497 #define drbd_free_peer_req(m,e) __drbd_free_peer_req(m, e, 0) 1498 #define drbd_free_net_peer_req(m,e) __drbd_free_peer_req(m, e, 1) 1499 extern struct page *drbd_alloc_pages(struct drbd_peer_device *, unsigned int, bool); 1500 extern void drbd_set_recv_tcq(struct drbd_device *device, int tcq_enabled); 1501 extern void _drbd_clear_done_ee(struct drbd_device *device, struct list_head *to_be_freed); 1502 extern int drbd_connected(struct drbd_peer_device *); 1503 1504 /* sets the number of 512 byte sectors of our virtual device */ 1505 void drbd_set_my_capacity(struct drbd_device *device, sector_t size); 1506 1507 /* 1508 * used to submit our private bio 1509 */ 1510 static inline void drbd_submit_bio_noacct(struct drbd_device *device, 1511 int fault_type, struct bio *bio) 1512 { 1513 __release(local); 1514 if (!bio->bi_bdev) { 1515 drbd_err(device, "drbd_submit_bio_noacct: bio->bi_bdev == NULL\n"); 1516 bio->bi_status = BLK_STS_IOERR; 1517 bio_endio(bio); 1518 return; 1519 } 1520 1521 if (drbd_insert_fault(device, fault_type)) 1522 bio_io_error(bio); 1523 else 1524 submit_bio_noacct(bio); 1525 } 1526 1527 void drbd_bump_write_ordering(struct drbd_resource *resource, struct drbd_backing_dev *bdev, 1528 enum write_ordering_e wo); 1529 1530 /* drbd_proc.c */ 1531 extern struct proc_dir_entry *drbd_proc; 1532 int drbd_seq_show(struct seq_file *seq, void *v); 1533 1534 /* drbd_actlog.c */ 1535 extern bool drbd_al_begin_io_prepare(struct drbd_device *device, struct drbd_interval *i); 1536 extern int drbd_al_begin_io_nonblock(struct drbd_device *device, struct drbd_interval *i); 1537 extern void drbd_al_begin_io_commit(struct drbd_device *device); 1538 extern bool drbd_al_begin_io_fastpath(struct drbd_device *device, struct drbd_interval *i); 1539 extern void drbd_al_begin_io(struct drbd_device *device, struct drbd_interval *i); 1540 extern void drbd_al_complete_io(struct drbd_device *device, struct drbd_interval *i); 1541 extern void drbd_rs_complete_io(struct drbd_device *device, sector_t sector); 1542 extern int drbd_rs_begin_io(struct drbd_device *device, sector_t sector); 1543 extern int drbd_try_rs_begin_io(struct drbd_device *device, sector_t sector); 1544 extern void drbd_rs_cancel_all(struct drbd_device *device); 1545 extern int drbd_rs_del_all(struct drbd_device *device); 1546 extern void drbd_rs_failed_io(struct drbd_device *device, 1547 sector_t sector, int size); 1548 extern void drbd_advance_rs_marks(struct drbd_device *device, unsigned long still_to_go); 1549 1550 enum update_sync_bits_mode { RECORD_RS_FAILED, SET_OUT_OF_SYNC, SET_IN_SYNC }; 1551 extern int __drbd_change_sync(struct drbd_device *device, sector_t sector, int size, 1552 enum update_sync_bits_mode mode); 1553 #define drbd_set_in_sync(device, sector, size) \ 1554 __drbd_change_sync(device, sector, size, SET_IN_SYNC) 1555 #define drbd_set_out_of_sync(device, sector, size) \ 1556 __drbd_change_sync(device, sector, size, SET_OUT_OF_SYNC) 1557 #define drbd_rs_failed_io(device, sector, size) \ 1558 __drbd_change_sync(device, sector, size, RECORD_RS_FAILED) 1559 extern void drbd_al_shrink(struct drbd_device *device); 1560 extern int drbd_al_initialize(struct drbd_device *, void *); 1561 1562 /* drbd_nl.c */ 1563 /* state info broadcast */ 1564 struct sib_info { 1565 enum drbd_state_info_bcast_reason sib_reason; 1566 union { 1567 struct { 1568 char *helper_name; 1569 unsigned helper_exit_code; 1570 }; 1571 struct { 1572 union drbd_state os; 1573 union drbd_state ns; 1574 }; 1575 }; 1576 }; 1577 void drbd_bcast_event(struct drbd_device *device, const struct sib_info *sib); 1578 1579 extern int notify_resource_state(struct sk_buff *, 1580 unsigned int, 1581 struct drbd_resource *, 1582 struct resource_info *, 1583 enum drbd_notification_type); 1584 extern int notify_device_state(struct sk_buff *, 1585 unsigned int, 1586 struct drbd_device *, 1587 struct device_info *, 1588 enum drbd_notification_type); 1589 extern int notify_connection_state(struct sk_buff *, 1590 unsigned int, 1591 struct drbd_connection *, 1592 struct connection_info *, 1593 enum drbd_notification_type); 1594 extern int notify_peer_device_state(struct sk_buff *, 1595 unsigned int, 1596 struct drbd_peer_device *, 1597 struct peer_device_info *, 1598 enum drbd_notification_type); 1599 extern void notify_helper(enum drbd_notification_type, struct drbd_device *, 1600 struct drbd_connection *, const char *, int); 1601 1602 /* 1603 * inline helper functions 1604 *************************/ 1605 1606 /* see also page_chain_add and friends in drbd_receiver.c */ 1607 static inline struct page *page_chain_next(struct page *page) 1608 { 1609 return (struct page *)page_private(page); 1610 } 1611 #define page_chain_for_each(page) \ 1612 for (; page && ({ prefetch(page_chain_next(page)); 1; }); \ 1613 page = page_chain_next(page)) 1614 #define page_chain_for_each_safe(page, n) \ 1615 for (; page && ({ n = page_chain_next(page); 1; }); page = n) 1616 1617 1618 static inline int drbd_peer_req_has_active_page(struct drbd_peer_request *peer_req) 1619 { 1620 struct page *page = peer_req->pages; 1621 page_chain_for_each(page) { 1622 if (page_count(page) > 1) 1623 return 1; 1624 } 1625 return 0; 1626 } 1627 1628 static inline union drbd_state drbd_read_state(struct drbd_device *device) 1629 { 1630 struct drbd_resource *resource = device->resource; 1631 union drbd_state rv; 1632 1633 rv.i = device->state.i; 1634 rv.susp = resource->susp; 1635 rv.susp_nod = resource->susp_nod; 1636 rv.susp_fen = resource->susp_fen; 1637 1638 return rv; 1639 } 1640 1641 enum drbd_force_detach_flags { 1642 DRBD_READ_ERROR, 1643 DRBD_WRITE_ERROR, 1644 DRBD_META_IO_ERROR, 1645 DRBD_FORCE_DETACH, 1646 }; 1647 1648 #define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__) 1649 static inline void __drbd_chk_io_error_(struct drbd_device *device, 1650 enum drbd_force_detach_flags df, 1651 const char *where) 1652 { 1653 enum drbd_io_error_p ep; 1654 1655 rcu_read_lock(); 1656 ep = rcu_dereference(device->ldev->disk_conf)->on_io_error; 1657 rcu_read_unlock(); 1658 switch (ep) { 1659 case EP_PASS_ON: /* FIXME would this be better named "Ignore"? */ 1660 if (df == DRBD_READ_ERROR || df == DRBD_WRITE_ERROR) { 1661 if (drbd_ratelimit()) 1662 drbd_err(device, "Local IO failed in %s.\n", where); 1663 if (device->state.disk > D_INCONSISTENT) 1664 _drbd_set_state(_NS(device, disk, D_INCONSISTENT), CS_HARD, NULL); 1665 break; 1666 } 1667 fallthrough; /* for DRBD_META_IO_ERROR or DRBD_FORCE_DETACH */ 1668 case EP_DETACH: 1669 case EP_CALL_HELPER: 1670 /* Remember whether we saw a READ or WRITE error. 1671 * 1672 * Recovery of the affected area for WRITE failure is covered 1673 * by the activity log. 1674 * READ errors may fall outside that area though. Certain READ 1675 * errors can be "healed" by writing good data to the affected 1676 * blocks, which triggers block re-allocation in lower layers. 1677 * 1678 * If we can not write the bitmap after a READ error, 1679 * we may need to trigger a full sync (see w_go_diskless()). 1680 * 1681 * Force-detach is not really an IO error, but rather a 1682 * desperate measure to try to deal with a completely 1683 * unresponsive lower level IO stack. 1684 * Still it should be treated as a WRITE error. 1685 * 1686 * Meta IO error is always WRITE error: 1687 * we read meta data only once during attach, 1688 * which will fail in case of errors. 1689 */ 1690 set_bit(WAS_IO_ERROR, &device->flags); 1691 if (df == DRBD_READ_ERROR) 1692 set_bit(WAS_READ_ERROR, &device->flags); 1693 if (df == DRBD_FORCE_DETACH) 1694 set_bit(FORCE_DETACH, &device->flags); 1695 if (device->state.disk > D_FAILED) { 1696 _drbd_set_state(_NS(device, disk, D_FAILED), CS_HARD, NULL); 1697 drbd_err(device, 1698 "Local IO failed in %s. Detaching...\n", where); 1699 } 1700 break; 1701 } 1702 } 1703 1704 /** 1705 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers 1706 * @device: DRBD device. 1707 * @error: Error code passed to the IO completion callback 1708 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data 1709 * 1710 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED) 1711 */ 1712 #define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__) 1713 static inline void drbd_chk_io_error_(struct drbd_device *device, 1714 int error, enum drbd_force_detach_flags forcedetach, const char *where) 1715 { 1716 if (error) { 1717 unsigned long flags; 1718 spin_lock_irqsave(&device->resource->req_lock, flags); 1719 __drbd_chk_io_error_(device, forcedetach, where); 1720 spin_unlock_irqrestore(&device->resource->req_lock, flags); 1721 } 1722 } 1723 1724 1725 /** 1726 * drbd_md_first_sector() - Returns the first sector number of the meta data area 1727 * @bdev: Meta data block device. 1728 * 1729 * BTW, for internal meta data, this happens to be the maximum capacity 1730 * we could agree upon with our peer node. 1731 */ 1732 static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev) 1733 { 1734 switch (bdev->md.meta_dev_idx) { 1735 case DRBD_MD_INDEX_INTERNAL: 1736 case DRBD_MD_INDEX_FLEX_INT: 1737 return bdev->md.md_offset + bdev->md.bm_offset; 1738 case DRBD_MD_INDEX_FLEX_EXT: 1739 default: 1740 return bdev->md.md_offset; 1741 } 1742 } 1743 1744 /** 1745 * drbd_md_last_sector() - Return the last sector number of the meta data area 1746 * @bdev: Meta data block device. 1747 */ 1748 static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev) 1749 { 1750 switch (bdev->md.meta_dev_idx) { 1751 case DRBD_MD_INDEX_INTERNAL: 1752 case DRBD_MD_INDEX_FLEX_INT: 1753 return bdev->md.md_offset + MD_4kB_SECT -1; 1754 case DRBD_MD_INDEX_FLEX_EXT: 1755 default: 1756 return bdev->md.md_offset + bdev->md.md_size_sect -1; 1757 } 1758 } 1759 1760 /* Returns the number of 512 byte sectors of the device */ 1761 static inline sector_t drbd_get_capacity(struct block_device *bdev) 1762 { 1763 return bdev ? bdev_nr_sectors(bdev) : 0; 1764 } 1765 1766 /** 1767 * drbd_get_max_capacity() - Returns the capacity we announce to out peer 1768 * @bdev: Meta data block device. 1769 * 1770 * returns the capacity we announce to out peer. we clip ourselves at the 1771 * various MAX_SECTORS, because if we don't, current implementation will 1772 * oops sooner or later 1773 */ 1774 static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev) 1775 { 1776 sector_t s; 1777 1778 switch (bdev->md.meta_dev_idx) { 1779 case DRBD_MD_INDEX_INTERNAL: 1780 case DRBD_MD_INDEX_FLEX_INT: 1781 s = drbd_get_capacity(bdev->backing_bdev) 1782 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1783 drbd_md_first_sector(bdev)) 1784 : 0; 1785 break; 1786 case DRBD_MD_INDEX_FLEX_EXT: 1787 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1788 drbd_get_capacity(bdev->backing_bdev)); 1789 /* clip at maximum size the meta device can support */ 1790 s = min_t(sector_t, s, 1791 BM_EXT_TO_SECT(bdev->md.md_size_sect 1792 - bdev->md.bm_offset)); 1793 break; 1794 default: 1795 s = min_t(sector_t, DRBD_MAX_SECTORS, 1796 drbd_get_capacity(bdev->backing_bdev)); 1797 } 1798 return s; 1799 } 1800 1801 /** 1802 * drbd_md_ss() - Return the sector number of our meta data super block 1803 * @bdev: Meta data block device. 1804 */ 1805 static inline sector_t drbd_md_ss(struct drbd_backing_dev *bdev) 1806 { 1807 const int meta_dev_idx = bdev->md.meta_dev_idx; 1808 1809 if (meta_dev_idx == DRBD_MD_INDEX_FLEX_EXT) 1810 return 0; 1811 1812 /* Since drbd08, internal meta data is always "flexible". 1813 * position: last 4k aligned block of 4k size */ 1814 if (meta_dev_idx == DRBD_MD_INDEX_INTERNAL || 1815 meta_dev_idx == DRBD_MD_INDEX_FLEX_INT) 1816 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL) - 8; 1817 1818 /* external, some index; this is the old fixed size layout */ 1819 return MD_128MB_SECT * bdev->md.meta_dev_idx; 1820 } 1821 1822 static inline void 1823 drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 1824 { 1825 unsigned long flags; 1826 spin_lock_irqsave(&q->q_lock, flags); 1827 list_add_tail(&w->list, &q->q); 1828 spin_unlock_irqrestore(&q->q_lock, flags); 1829 wake_up(&q->q_wait); 1830 } 1831 1832 static inline void 1833 drbd_queue_work_if_unqueued(struct drbd_work_queue *q, struct drbd_work *w) 1834 { 1835 unsigned long flags; 1836 spin_lock_irqsave(&q->q_lock, flags); 1837 if (list_empty_careful(&w->list)) 1838 list_add_tail(&w->list, &q->q); 1839 spin_unlock_irqrestore(&q->q_lock, flags); 1840 wake_up(&q->q_wait); 1841 } 1842 1843 static inline void 1844 drbd_device_post_work(struct drbd_device *device, int work_bit) 1845 { 1846 if (!test_and_set_bit(work_bit, &device->flags)) { 1847 struct drbd_connection *connection = 1848 first_peer_device(device)->connection; 1849 struct drbd_work_queue *q = &connection->sender_work; 1850 if (!test_and_set_bit(DEVICE_WORK_PENDING, &connection->flags)) 1851 wake_up(&q->q_wait); 1852 } 1853 } 1854 1855 extern void drbd_flush_workqueue(struct drbd_work_queue *work_queue); 1856 1857 /* To get the ack_receiver out of the blocking network stack, 1858 * so it can change its sk_rcvtimeo from idle- to ping-timeout, 1859 * and send a ping, we need to send a signal. 1860 * Which signal we send is irrelevant. */ 1861 static inline void wake_ack_receiver(struct drbd_connection *connection) 1862 { 1863 struct task_struct *task = connection->ack_receiver.task; 1864 if (task && get_t_state(&connection->ack_receiver) == RUNNING) 1865 send_sig(SIGXCPU, task, 1); 1866 } 1867 1868 static inline void request_ping(struct drbd_connection *connection) 1869 { 1870 set_bit(SEND_PING, &connection->flags); 1871 wake_ack_receiver(connection); 1872 } 1873 1874 extern void *conn_prepare_command(struct drbd_connection *, struct drbd_socket *); 1875 extern void *drbd_prepare_command(struct drbd_peer_device *, struct drbd_socket *); 1876 extern int conn_send_command(struct drbd_connection *, struct drbd_socket *, 1877 enum drbd_packet, unsigned int, void *, 1878 unsigned int); 1879 extern int drbd_send_command(struct drbd_peer_device *, struct drbd_socket *, 1880 enum drbd_packet, unsigned int, void *, 1881 unsigned int); 1882 1883 extern int drbd_send_ping(struct drbd_connection *connection); 1884 extern int drbd_send_ping_ack(struct drbd_connection *connection); 1885 extern int drbd_send_state_req(struct drbd_peer_device *, union drbd_state, union drbd_state); 1886 extern int conn_send_state_req(struct drbd_connection *, union drbd_state, union drbd_state); 1887 1888 static inline void drbd_thread_stop(struct drbd_thread *thi) 1889 { 1890 _drbd_thread_stop(thi, false, true); 1891 } 1892 1893 static inline void drbd_thread_stop_nowait(struct drbd_thread *thi) 1894 { 1895 _drbd_thread_stop(thi, false, false); 1896 } 1897 1898 static inline void drbd_thread_restart_nowait(struct drbd_thread *thi) 1899 { 1900 _drbd_thread_stop(thi, true, false); 1901 } 1902 1903 /* counts how many answer packets packets we expect from our peer, 1904 * for either explicit application requests, 1905 * or implicit barrier packets as necessary. 1906 * increased: 1907 * w_send_barrier 1908 * _req_mod(req, QUEUE_FOR_NET_WRITE or QUEUE_FOR_NET_READ); 1909 * it is much easier and equally valid to count what we queue for the 1910 * worker, even before it actually was queued or send. 1911 * (drbd_make_request_common; recovery path on read io-error) 1912 * decreased: 1913 * got_BarrierAck (respective tl_clear, tl_clear_barrier) 1914 * _req_mod(req, DATA_RECEIVED) 1915 * [from receive_DataReply] 1916 * _req_mod(req, WRITE_ACKED_BY_PEER or RECV_ACKED_BY_PEER or NEG_ACKED) 1917 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)] 1918 * for some reason it is NOT decreased in got_NegAck, 1919 * but in the resulting cleanup code from report_params. 1920 * we should try to remember the reason for that... 1921 * _req_mod(req, SEND_FAILED or SEND_CANCELED) 1922 * _req_mod(req, CONNECTION_LOST_WHILE_PENDING) 1923 * [from tl_clear_barrier] 1924 */ 1925 static inline void inc_ap_pending(struct drbd_device *device) 1926 { 1927 atomic_inc(&device->ap_pending_cnt); 1928 } 1929 1930 #define ERR_IF_CNT_IS_NEGATIVE(which, func, line) \ 1931 if (atomic_read(&device->which) < 0) \ 1932 drbd_err(device, "in %s:%d: " #which " = %d < 0 !\n", \ 1933 func, line, \ 1934 atomic_read(&device->which)) 1935 1936 #define dec_ap_pending(device) _dec_ap_pending(device, __func__, __LINE__) 1937 static inline void _dec_ap_pending(struct drbd_device *device, const char *func, int line) 1938 { 1939 if (atomic_dec_and_test(&device->ap_pending_cnt)) 1940 wake_up(&device->misc_wait); 1941 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt, func, line); 1942 } 1943 1944 /* counts how many resync-related answers we still expect from the peer 1945 * increase decrease 1946 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY) 1947 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK with ID_SYNCER) 1948 * (or P_NEG_ACK with ID_SYNCER) 1949 */ 1950 static inline void inc_rs_pending(struct drbd_device *device) 1951 { 1952 atomic_inc(&device->rs_pending_cnt); 1953 } 1954 1955 #define dec_rs_pending(device) _dec_rs_pending(device, __func__, __LINE__) 1956 static inline void _dec_rs_pending(struct drbd_device *device, const char *func, int line) 1957 { 1958 atomic_dec(&device->rs_pending_cnt); 1959 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt, func, line); 1960 } 1961 1962 /* counts how many answers we still need to send to the peer. 1963 * increased on 1964 * receive_Data unless protocol A; 1965 * we need to send a P_RECV_ACK (proto B) 1966 * or P_WRITE_ACK (proto C) 1967 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK 1968 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA 1969 * receive_Barrier_* we need to send a P_BARRIER_ACK 1970 */ 1971 static inline void inc_unacked(struct drbd_device *device) 1972 { 1973 atomic_inc(&device->unacked_cnt); 1974 } 1975 1976 #define dec_unacked(device) _dec_unacked(device, __func__, __LINE__) 1977 static inline void _dec_unacked(struct drbd_device *device, const char *func, int line) 1978 { 1979 atomic_dec(&device->unacked_cnt); 1980 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line); 1981 } 1982 1983 #define sub_unacked(device, n) _sub_unacked(device, n, __func__, __LINE__) 1984 static inline void _sub_unacked(struct drbd_device *device, int n, const char *func, int line) 1985 { 1986 atomic_sub(n, &device->unacked_cnt); 1987 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line); 1988 } 1989 1990 static inline bool is_sync_target_state(enum drbd_conns connection_state) 1991 { 1992 return connection_state == C_SYNC_TARGET || 1993 connection_state == C_PAUSED_SYNC_T; 1994 } 1995 1996 static inline bool is_sync_source_state(enum drbd_conns connection_state) 1997 { 1998 return connection_state == C_SYNC_SOURCE || 1999 connection_state == C_PAUSED_SYNC_S; 2000 } 2001 2002 static inline bool is_sync_state(enum drbd_conns connection_state) 2003 { 2004 return is_sync_source_state(connection_state) || 2005 is_sync_target_state(connection_state); 2006 } 2007 2008 /** 2009 * get_ldev() - Increase the ref count on device->ldev. Returns 0 if there is no ldev 2010 * @_device: DRBD device. 2011 * @_min_state: Minimum device state required for success. 2012 * 2013 * You have to call put_ldev() when finished working with device->ldev. 2014 */ 2015 #define get_ldev_if_state(_device, _min_state) \ 2016 (_get_ldev_if_state((_device), (_min_state)) ? \ 2017 ({ __acquire(x); true; }) : false) 2018 #define get_ldev(_device) get_ldev_if_state(_device, D_INCONSISTENT) 2019 2020 static inline void put_ldev(struct drbd_device *device) 2021 { 2022 enum drbd_disk_state disk_state = device->state.disk; 2023 /* We must check the state *before* the atomic_dec becomes visible, 2024 * or we have a theoretical race where someone hitting zero, 2025 * while state still D_FAILED, will then see D_DISKLESS in the 2026 * condition below and calling into destroy, where he must not, yet. */ 2027 int i = atomic_dec_return(&device->local_cnt); 2028 2029 /* This may be called from some endio handler, 2030 * so we must not sleep here. */ 2031 2032 __release(local); 2033 D_ASSERT(device, i >= 0); 2034 if (i == 0) { 2035 if (disk_state == D_DISKLESS) 2036 /* even internal references gone, safe to destroy */ 2037 drbd_device_post_work(device, DESTROY_DISK); 2038 if (disk_state == D_FAILED) 2039 /* all application IO references gone. */ 2040 if (!test_and_set_bit(GOING_DISKLESS, &device->flags)) 2041 drbd_device_post_work(device, GO_DISKLESS); 2042 wake_up(&device->misc_wait); 2043 } 2044 } 2045 2046 #ifndef __CHECKER__ 2047 static inline int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins) 2048 { 2049 int io_allowed; 2050 2051 /* never get a reference while D_DISKLESS */ 2052 if (device->state.disk == D_DISKLESS) 2053 return 0; 2054 2055 atomic_inc(&device->local_cnt); 2056 io_allowed = (device->state.disk >= mins); 2057 if (!io_allowed) 2058 put_ldev(device); 2059 return io_allowed; 2060 } 2061 #else 2062 extern int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins); 2063 #endif 2064 2065 /* this throttles on-the-fly application requests 2066 * according to max_buffers settings; 2067 * maybe re-implement using semaphores? */ 2068 static inline int drbd_get_max_buffers(struct drbd_device *device) 2069 { 2070 struct net_conf *nc; 2071 int mxb; 2072 2073 rcu_read_lock(); 2074 nc = rcu_dereference(first_peer_device(device)->connection->net_conf); 2075 mxb = nc ? nc->max_buffers : 1000000; /* arbitrary limit on open requests */ 2076 rcu_read_unlock(); 2077 2078 return mxb; 2079 } 2080 2081 static inline int drbd_state_is_stable(struct drbd_device *device) 2082 { 2083 union drbd_dev_state s = device->state; 2084 2085 /* DO NOT add a default clause, we want the compiler to warn us 2086 * for any newly introduced state we may have forgotten to add here */ 2087 2088 switch ((enum drbd_conns)s.conn) { 2089 /* new io only accepted when there is no connection, ... */ 2090 case C_STANDALONE: 2091 case C_WF_CONNECTION: 2092 /* ... or there is a well established connection. */ 2093 case C_CONNECTED: 2094 case C_SYNC_SOURCE: 2095 case C_SYNC_TARGET: 2096 case C_VERIFY_S: 2097 case C_VERIFY_T: 2098 case C_PAUSED_SYNC_S: 2099 case C_PAUSED_SYNC_T: 2100 case C_AHEAD: 2101 case C_BEHIND: 2102 /* transitional states, IO allowed */ 2103 case C_DISCONNECTING: 2104 case C_UNCONNECTED: 2105 case C_TIMEOUT: 2106 case C_BROKEN_PIPE: 2107 case C_NETWORK_FAILURE: 2108 case C_PROTOCOL_ERROR: 2109 case C_TEAR_DOWN: 2110 case C_WF_REPORT_PARAMS: 2111 case C_STARTING_SYNC_S: 2112 case C_STARTING_SYNC_T: 2113 break; 2114 2115 /* Allow IO in BM exchange states with new protocols */ 2116 case C_WF_BITMAP_S: 2117 if (first_peer_device(device)->connection->agreed_pro_version < 96) 2118 return 0; 2119 break; 2120 2121 /* no new io accepted in these states */ 2122 case C_WF_BITMAP_T: 2123 case C_WF_SYNC_UUID: 2124 case C_MASK: 2125 /* not "stable" */ 2126 return 0; 2127 } 2128 2129 switch ((enum drbd_disk_state)s.disk) { 2130 case D_DISKLESS: 2131 case D_INCONSISTENT: 2132 case D_OUTDATED: 2133 case D_CONSISTENT: 2134 case D_UP_TO_DATE: 2135 case D_FAILED: 2136 /* disk state is stable as well. */ 2137 break; 2138 2139 /* no new io accepted during transitional states */ 2140 case D_ATTACHING: 2141 case D_NEGOTIATING: 2142 case D_UNKNOWN: 2143 case D_MASK: 2144 /* not "stable" */ 2145 return 0; 2146 } 2147 2148 return 1; 2149 } 2150 2151 static inline int drbd_suspended(struct drbd_device *device) 2152 { 2153 struct drbd_resource *resource = device->resource; 2154 2155 return resource->susp || resource->susp_fen || resource->susp_nod; 2156 } 2157 2158 static inline bool may_inc_ap_bio(struct drbd_device *device) 2159 { 2160 int mxb = drbd_get_max_buffers(device); 2161 2162 if (drbd_suspended(device)) 2163 return false; 2164 if (atomic_read(&device->suspend_cnt)) 2165 return false; 2166 2167 /* to avoid potential deadlock or bitmap corruption, 2168 * in various places, we only allow new application io 2169 * to start during "stable" states. */ 2170 2171 /* no new io accepted when attaching or detaching the disk */ 2172 if (!drbd_state_is_stable(device)) 2173 return false; 2174 2175 /* since some older kernels don't have atomic_add_unless, 2176 * and we are within the spinlock anyways, we have this workaround. */ 2177 if (atomic_read(&device->ap_bio_cnt) > mxb) 2178 return false; 2179 if (test_bit(BITMAP_IO, &device->flags)) 2180 return false; 2181 return true; 2182 } 2183 2184 static inline bool inc_ap_bio_cond(struct drbd_device *device) 2185 { 2186 bool rv = false; 2187 2188 spin_lock_irq(&device->resource->req_lock); 2189 rv = may_inc_ap_bio(device); 2190 if (rv) 2191 atomic_inc(&device->ap_bio_cnt); 2192 spin_unlock_irq(&device->resource->req_lock); 2193 2194 return rv; 2195 } 2196 2197 static inline void inc_ap_bio(struct drbd_device *device) 2198 { 2199 /* we wait here 2200 * as long as the device is suspended 2201 * until the bitmap is no longer on the fly during connection 2202 * handshake as long as we would exceed the max_buffer limit. 2203 * 2204 * to avoid races with the reconnect code, 2205 * we need to atomic_inc within the spinlock. */ 2206 2207 wait_event(device->misc_wait, inc_ap_bio_cond(device)); 2208 } 2209 2210 static inline void dec_ap_bio(struct drbd_device *device) 2211 { 2212 int mxb = drbd_get_max_buffers(device); 2213 int ap_bio = atomic_dec_return(&device->ap_bio_cnt); 2214 2215 D_ASSERT(device, ap_bio >= 0); 2216 2217 if (ap_bio == 0 && test_bit(BITMAP_IO, &device->flags)) { 2218 if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags)) 2219 drbd_queue_work(&first_peer_device(device)-> 2220 connection->sender_work, 2221 &device->bm_io_work.w); 2222 } 2223 2224 /* this currently does wake_up for every dec_ap_bio! 2225 * maybe rather introduce some type of hysteresis? 2226 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */ 2227 if (ap_bio < mxb) 2228 wake_up(&device->misc_wait); 2229 } 2230 2231 static inline bool verify_can_do_stop_sector(struct drbd_device *device) 2232 { 2233 return first_peer_device(device)->connection->agreed_pro_version >= 97 && 2234 first_peer_device(device)->connection->agreed_pro_version != 100; 2235 } 2236 2237 static inline int drbd_set_ed_uuid(struct drbd_device *device, u64 val) 2238 { 2239 int changed = device->ed_uuid != val; 2240 device->ed_uuid = val; 2241 return changed; 2242 } 2243 2244 static inline int drbd_queue_order_type(struct drbd_device *device) 2245 { 2246 /* sorry, we currently have no working implementation 2247 * of distributed TCQ stuff */ 2248 #ifndef QUEUE_ORDERED_NONE 2249 #define QUEUE_ORDERED_NONE 0 2250 #endif 2251 return QUEUE_ORDERED_NONE; 2252 } 2253 2254 static inline struct drbd_connection *first_connection(struct drbd_resource *resource) 2255 { 2256 return list_first_entry_or_null(&resource->connections, 2257 struct drbd_connection, connections); 2258 } 2259 2260 #endif 2261