1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 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 41 #ifdef __CHECKER__ 42 # define __protected_by(x) __attribute__((require_context(x,1,999,"rdwr"))) 43 # define __protected_read_by(x) __attribute__((require_context(x,1,999,"read"))) 44 # define __protected_write_by(x) __attribute__((require_context(x,1,999,"write"))) 45 #else 46 # define __protected_by(x) 47 # define __protected_read_by(x) 48 # define __protected_write_by(x) 49 #endif 50 51 /* shared module parameters, defined in drbd_main.c */ 52 #ifdef CONFIG_DRBD_FAULT_INJECTION 53 extern int drbd_enable_faults; 54 extern int drbd_fault_rate; 55 #endif 56 57 extern unsigned int drbd_minor_count; 58 extern char drbd_usermode_helper[]; 59 extern int drbd_proc_details; 60 61 62 /* This is used to stop/restart our threads. 63 * Cannot use SIGTERM nor SIGKILL, since these 64 * are sent out by init on runlevel changes 65 * I choose SIGHUP for now. 66 */ 67 #define DRBD_SIGKILL SIGHUP 68 69 #define ID_IN_SYNC (4711ULL) 70 #define ID_OUT_OF_SYNC (4712ULL) 71 #define ID_SYNCER (-1ULL) 72 73 #define UUID_NEW_BM_OFFSET ((u64)0x0001000000000000ULL) 74 75 struct drbd_device; 76 struct drbd_connection; 77 78 #define __drbd_printk_device(level, device, fmt, args...) \ 79 dev_printk(level, disk_to_dev((device)->vdisk), fmt, ## args) 80 #define __drbd_printk_peer_device(level, peer_device, fmt, args...) \ 81 dev_printk(level, disk_to_dev((peer_device)->device->vdisk), fmt, ## args) 82 #define __drbd_printk_resource(level, resource, fmt, args...) \ 83 printk(level "drbd %s: " fmt, (resource)->name, ## args) 84 #define __drbd_printk_connection(level, connection, fmt, args...) \ 85 printk(level "drbd %s: " fmt, (connection)->resource->name, ## args) 86 87 void drbd_printk_with_wrong_object_type(void); 88 89 #define __drbd_printk_if_same_type(obj, type, func, level, fmt, args...) \ 90 (__builtin_types_compatible_p(typeof(obj), type) || \ 91 __builtin_types_compatible_p(typeof(obj), const type)), \ 92 func(level, (const type)(obj), fmt, ## args) 93 94 #define drbd_printk(level, obj, fmt, args...) \ 95 __builtin_choose_expr( \ 96 __drbd_printk_if_same_type(obj, struct drbd_device *, \ 97 __drbd_printk_device, level, fmt, ## args), \ 98 __builtin_choose_expr( \ 99 __drbd_printk_if_same_type(obj, struct drbd_resource *, \ 100 __drbd_printk_resource, level, fmt, ## args), \ 101 __builtin_choose_expr( \ 102 __drbd_printk_if_same_type(obj, struct drbd_connection *, \ 103 __drbd_printk_connection, level, fmt, ## args), \ 104 __builtin_choose_expr( \ 105 __drbd_printk_if_same_type(obj, struct drbd_peer_device *, \ 106 __drbd_printk_peer_device, level, fmt, ## args), \ 107 drbd_printk_with_wrong_object_type())))) 108 109 #define drbd_dbg(obj, fmt, args...) \ 110 drbd_printk(KERN_DEBUG, obj, fmt, ## args) 111 #define drbd_alert(obj, fmt, args...) \ 112 drbd_printk(KERN_ALERT, obj, fmt, ## args) 113 #define drbd_err(obj, fmt, args...) \ 114 drbd_printk(KERN_ERR, obj, fmt, ## args) 115 #define drbd_warn(obj, fmt, args...) \ 116 drbd_printk(KERN_WARNING, obj, fmt, ## args) 117 #define drbd_info(obj, fmt, args...) \ 118 drbd_printk(KERN_INFO, obj, fmt, ## args) 119 #define drbd_emerg(obj, fmt, args...) \ 120 drbd_printk(KERN_EMERG, obj, fmt, ## args) 121 122 #define dynamic_drbd_dbg(device, fmt, args...) \ 123 dynamic_dev_dbg(disk_to_dev(device->vdisk), fmt, ## args) 124 125 #define D_ASSERT(device, exp) do { \ 126 if (!(exp)) \ 127 drbd_err(device, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__); \ 128 } while (0) 129 130 /** 131 * expect - Make an assertion 132 * 133 * Unlike the assert macro, this macro returns a boolean result. 134 */ 135 #define expect(exp) ({ \ 136 bool _bool = (exp); \ 137 if (!_bool) \ 138 drbd_err(device, "ASSERTION %s FAILED in %s\n", \ 139 #exp, __func__); \ 140 _bool; \ 141 }) 142 143 /* Defines to control fault insertion */ 144 enum { 145 DRBD_FAULT_MD_WR = 0, /* meta data write */ 146 DRBD_FAULT_MD_RD = 1, /* read */ 147 DRBD_FAULT_RS_WR = 2, /* resync */ 148 DRBD_FAULT_RS_RD = 3, 149 DRBD_FAULT_DT_WR = 4, /* data */ 150 DRBD_FAULT_DT_RD = 5, 151 DRBD_FAULT_DT_RA = 6, /* data read ahead */ 152 DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */ 153 DRBD_FAULT_AL_EE = 8, /* alloc ee */ 154 DRBD_FAULT_RECEIVE = 9, /* Changes some bytes upon receiving a [rs]data block */ 155 156 DRBD_FAULT_MAX, 157 }; 158 159 extern unsigned int 160 _drbd_insert_fault(struct drbd_device *device, unsigned int type); 161 162 static inline int 163 drbd_insert_fault(struct drbd_device *device, unsigned int type) { 164 #ifdef CONFIG_DRBD_FAULT_INJECTION 165 return drbd_fault_rate && 166 (drbd_enable_faults & (1<<type)) && 167 _drbd_insert_fault(device, type); 168 #else 169 return 0; 170 #endif 171 } 172 173 /* integer division, round _UP_ to the next integer */ 174 #define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0)) 175 /* usual integer division */ 176 #define div_floor(A, B) ((A)/(B)) 177 178 extern struct ratelimit_state drbd_ratelimit_state; 179 extern struct idr drbd_devices; /* RCU, updates: genl_lock() */ 180 extern struct list_head drbd_resources; /* RCU, updates: genl_lock() */ 181 182 extern const char *cmdname(enum drbd_packet cmd); 183 184 /* for sending/receiving the bitmap, 185 * possibly in some encoding scheme */ 186 struct bm_xfer_ctx { 187 /* "const" 188 * stores total bits and long words 189 * of the bitmap, so we don't need to 190 * call the accessor functions over and again. */ 191 unsigned long bm_bits; 192 unsigned long bm_words; 193 /* during xfer, current position within the bitmap */ 194 unsigned long bit_offset; 195 unsigned long word_offset; 196 197 /* statistics; index: (h->command == P_BITMAP) */ 198 unsigned packets[2]; 199 unsigned bytes[2]; 200 }; 201 202 extern void INFO_bm_xfer_stats(struct drbd_device *device, 203 const char *direction, struct bm_xfer_ctx *c); 204 205 static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c) 206 { 207 /* word_offset counts "native long words" (32 or 64 bit), 208 * aligned at 64 bit. 209 * Encoded packet may end at an unaligned bit offset. 210 * In case a fallback clear text packet is transmitted in 211 * between, we adjust this offset back to the last 64bit 212 * aligned "native long word", which makes coding and decoding 213 * the plain text bitmap much more convenient. */ 214 #if BITS_PER_LONG == 64 215 c->word_offset = c->bit_offset >> 6; 216 #elif BITS_PER_LONG == 32 217 c->word_offset = c->bit_offset >> 5; 218 c->word_offset &= ~(1UL); 219 #else 220 # error "unsupported BITS_PER_LONG" 221 #endif 222 } 223 224 extern unsigned int drbd_header_size(struct drbd_connection *connection); 225 226 /**********************************************************************/ 227 enum drbd_thread_state { 228 NONE, 229 RUNNING, 230 EXITING, 231 RESTARTING 232 }; 233 234 struct drbd_thread { 235 spinlock_t t_lock; 236 struct task_struct *task; 237 struct completion stop; 238 enum drbd_thread_state t_state; 239 int (*function) (struct drbd_thread *); 240 struct drbd_resource *resource; 241 struct drbd_connection *connection; 242 int reset_cpu_mask; 243 const char *name; 244 }; 245 246 static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi) 247 { 248 /* THINK testing the t_state seems to be uncritical in all cases 249 * (but thread_{start,stop}), so we can read it *without* the lock. 250 * --lge */ 251 252 smp_rmb(); 253 return thi->t_state; 254 } 255 256 struct drbd_work { 257 struct list_head list; 258 int (*cb)(struct drbd_work *, int cancel); 259 }; 260 261 struct drbd_device_work { 262 struct drbd_work w; 263 struct drbd_device *device; 264 }; 265 266 #include "drbd_interval.h" 267 268 extern int drbd_wait_misc(struct drbd_device *, struct drbd_interval *); 269 270 extern void lock_all_resources(void); 271 extern void unlock_all_resources(void); 272 273 struct drbd_request { 274 struct drbd_work w; 275 struct drbd_device *device; 276 277 /* if local IO is not allowed, will be NULL. 278 * if local IO _is_ allowed, holds the locally submitted bio clone, 279 * or, after local IO completion, the ERR_PTR(error). 280 * see drbd_request_endio(). */ 281 struct bio *private_bio; 282 283 struct drbd_interval i; 284 285 /* epoch: used to check on "completion" whether this req was in 286 * the current epoch, and we therefore have to close it, 287 * causing a p_barrier packet to be send, starting a new epoch. 288 * 289 * This corresponds to "barrier" in struct p_barrier[_ack], 290 * and to "barrier_nr" in struct drbd_epoch (and various 291 * comments/function parameters/local variable names). 292 */ 293 unsigned int epoch; 294 295 struct list_head tl_requests; /* ring list in the transfer log */ 296 struct bio *master_bio; /* master bio pointer */ 297 298 /* see struct drbd_device */ 299 struct list_head req_pending_master_completion; 300 struct list_head req_pending_local; 301 302 /* for generic IO accounting */ 303 unsigned long start_jif; 304 305 /* for DRBD internal statistics */ 306 307 /* Minimal set of time stamps to determine if we wait for activity log 308 * transactions, local disk or peer. 32 bit "jiffies" are good enough, 309 * we don't expect a DRBD request to be stalled for several month. 310 */ 311 312 /* before actual request processing */ 313 unsigned long in_actlog_jif; 314 315 /* local disk */ 316 unsigned long pre_submit_jif; 317 318 /* per connection */ 319 unsigned long pre_send_jif; 320 unsigned long acked_jif; 321 unsigned long net_done_jif; 322 323 /* Possibly even more detail to track each phase: 324 * master_completion_jif 325 * how long did it take to complete the master bio 326 * (application visible latency) 327 * allocated_jif 328 * how long the master bio was blocked until we finally allocated 329 * a tracking struct 330 * in_actlog_jif 331 * how long did we wait for activity log transactions 332 * 333 * net_queued_jif 334 * when did we finally queue it for sending 335 * pre_send_jif 336 * when did we start sending it 337 * post_send_jif 338 * how long did we block in the network stack trying to send it 339 * acked_jif 340 * when did we receive (or fake, in protocol A) a remote ACK 341 * net_done_jif 342 * when did we receive final acknowledgement (P_BARRIER_ACK), 343 * or decide, e.g. on connection loss, that we do no longer expect 344 * anything from this peer for this request. 345 * 346 * pre_submit_jif 347 * post_sub_jif 348 * when did we start submiting to the lower level device, 349 * and how long did we block in that submit function 350 * local_completion_jif 351 * how long did it take the lower level device to complete this request 352 */ 353 354 355 /* once it hits 0, we may complete the master_bio */ 356 atomic_t completion_ref; 357 /* once it hits 0, we may destroy this drbd_request object */ 358 struct kref kref; 359 360 unsigned rq_state; /* see comments above _req_mod() */ 361 }; 362 363 struct drbd_epoch { 364 struct drbd_connection *connection; 365 struct list_head list; 366 unsigned int barrier_nr; 367 atomic_t epoch_size; /* increased on every request added. */ 368 atomic_t active; /* increased on every req. added, and dec on every finished. */ 369 unsigned long flags; 370 }; 371 372 /* Prototype declaration of function defined in drbd_receiver.c */ 373 int drbdd_init(struct drbd_thread *); 374 int drbd_asender(struct drbd_thread *); 375 376 /* drbd_epoch flag bits */ 377 enum { 378 DE_HAVE_BARRIER_NUMBER, 379 }; 380 381 enum epoch_event { 382 EV_PUT, 383 EV_GOT_BARRIER_NR, 384 EV_BECAME_LAST, 385 EV_CLEANUP = 32, /* used as flag */ 386 }; 387 388 struct digest_info { 389 int digest_size; 390 void *digest; 391 }; 392 393 struct drbd_peer_request { 394 struct drbd_work w; 395 struct drbd_peer_device *peer_device; 396 struct drbd_epoch *epoch; /* for writes */ 397 struct page *pages; 398 atomic_t pending_bios; 399 struct drbd_interval i; 400 /* see comments on ee flag bits below */ 401 unsigned long flags; 402 unsigned long submit_jif; 403 union { 404 u64 block_id; 405 struct digest_info *digest; 406 }; 407 }; 408 409 /* ee flag bits. 410 * While corresponding bios are in flight, the only modification will be 411 * set_bit WAS_ERROR, which has to be atomic. 412 * If no bios are in flight yet, or all have been completed, 413 * non-atomic modification to ee->flags is ok. 414 */ 415 enum { 416 __EE_CALL_AL_COMPLETE_IO, 417 __EE_MAY_SET_IN_SYNC, 418 419 /* is this a TRIM aka REQ_OP_DISCARD? */ 420 __EE_TRIM, 421 /* explicit zero-out requested, or 422 * our lower level cannot handle trim, 423 * and we want to fall back to zeroout instead */ 424 __EE_ZEROOUT, 425 426 /* In case a barrier failed, 427 * we need to resubmit without the barrier flag. */ 428 __EE_RESUBMITTED, 429 430 /* we may have several bios per peer request. 431 * if any of those fail, we set this flag atomically 432 * from the endio callback */ 433 __EE_WAS_ERROR, 434 435 /* This ee has a pointer to a digest instead of a block id */ 436 __EE_HAS_DIGEST, 437 438 /* Conflicting local requests need to be restarted after this request */ 439 __EE_RESTART_REQUESTS, 440 441 /* The peer wants a write ACK for this (wire proto C) */ 442 __EE_SEND_WRITE_ACK, 443 444 /* Is set when net_conf had two_primaries set while creating this peer_req */ 445 __EE_IN_INTERVAL_TREE, 446 447 /* for debugfs: */ 448 /* has this been submitted, or does it still wait for something else? */ 449 __EE_SUBMITTED, 450 451 /* this is/was a write request */ 452 __EE_WRITE, 453 454 /* this is/was a write same request */ 455 __EE_WRITE_SAME, 456 457 /* this originates from application on peer 458 * (not some resync or verify or other DRBD internal request) */ 459 __EE_APPLICATION, 460 461 /* If it contains only 0 bytes, send back P_RS_DEALLOCATED */ 462 __EE_RS_THIN_REQ, 463 }; 464 #define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO) 465 #define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC) 466 #define EE_TRIM (1<<__EE_TRIM) 467 #define EE_ZEROOUT (1<<__EE_ZEROOUT) 468 #define EE_RESUBMITTED (1<<__EE_RESUBMITTED) 469 #define EE_WAS_ERROR (1<<__EE_WAS_ERROR) 470 #define EE_HAS_DIGEST (1<<__EE_HAS_DIGEST) 471 #define EE_RESTART_REQUESTS (1<<__EE_RESTART_REQUESTS) 472 #define EE_SEND_WRITE_ACK (1<<__EE_SEND_WRITE_ACK) 473 #define EE_IN_INTERVAL_TREE (1<<__EE_IN_INTERVAL_TREE) 474 #define EE_SUBMITTED (1<<__EE_SUBMITTED) 475 #define EE_WRITE (1<<__EE_WRITE) 476 #define EE_WRITE_SAME (1<<__EE_WRITE_SAME) 477 #define EE_APPLICATION (1<<__EE_APPLICATION) 478 #define EE_RS_THIN_REQ (1<<__EE_RS_THIN_REQ) 479 480 /* flag bits per device */ 481 enum { 482 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */ 483 MD_DIRTY, /* current uuids and flags not yet on disk */ 484 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */ 485 CL_ST_CHG_SUCCESS, 486 CL_ST_CHG_FAIL, 487 CRASHED_PRIMARY, /* This node was a crashed primary. 488 * Gets cleared when the state.conn 489 * goes into C_CONNECTED state. */ 490 CONSIDER_RESYNC, 491 492 MD_NO_FUA, /* Users wants us to not use FUA/FLUSH on meta data dev */ 493 494 BITMAP_IO, /* suspend application io; 495 once no more io in flight, start bitmap io */ 496 BITMAP_IO_QUEUED, /* Started bitmap IO */ 497 WAS_IO_ERROR, /* Local disk failed, returned IO error */ 498 WAS_READ_ERROR, /* Local disk READ failed (set additionally to the above) */ 499 FORCE_DETACH, /* Force-detach from local disk, aborting any pending local IO */ 500 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */ 501 RESIZE_PENDING, /* Size change detected locally, waiting for the response from 502 * the peer, if it changed there as well. */ 503 NEW_CUR_UUID, /* Create new current UUID when thawing IO */ 504 AL_SUSPENDED, /* Activity logging is currently suspended. */ 505 AHEAD_TO_SYNC_SOURCE, /* Ahead -> SyncSource queued */ 506 B_RS_H_DONE, /* Before resync handler done (already executed) */ 507 DISCARD_MY_DATA, /* discard_my_data flag per volume */ 508 READ_BALANCE_RR, 509 510 FLUSH_PENDING, /* if set, device->flush_jif is when we submitted that flush 511 * from drbd_flush_after_epoch() */ 512 513 /* cleared only after backing device related structures have been destroyed. */ 514 GOING_DISKLESS, /* Disk is being detached, because of io-error, or admin request. */ 515 516 /* to be used in drbd_device_post_work() */ 517 GO_DISKLESS, /* tell worker to schedule cleanup before detach */ 518 DESTROY_DISK, /* tell worker to close backing devices and destroy related structures. */ 519 MD_SYNC, /* tell worker to call drbd_md_sync() */ 520 RS_START, /* tell worker to start resync/OV */ 521 RS_PROGRESS, /* tell worker that resync made significant progress */ 522 RS_DONE, /* tell worker that resync is done */ 523 }; 524 525 struct drbd_bitmap; /* opaque for drbd_device */ 526 527 /* definition of bits in bm_flags to be used in drbd_bm_lock 528 * and drbd_bitmap_io and friends. */ 529 enum bm_flag { 530 /* currently locked for bulk operation */ 531 BM_LOCKED_MASK = 0xf, 532 533 /* in detail, that is: */ 534 BM_DONT_CLEAR = 0x1, 535 BM_DONT_SET = 0x2, 536 BM_DONT_TEST = 0x4, 537 538 /* so we can mark it locked for bulk operation, 539 * and still allow all non-bulk operations */ 540 BM_IS_LOCKED = 0x8, 541 542 /* (test bit, count bit) allowed (common case) */ 543 BM_LOCKED_TEST_ALLOWED = BM_DONT_CLEAR | BM_DONT_SET | BM_IS_LOCKED, 544 545 /* testing bits, as well as setting new bits allowed, but clearing bits 546 * would be unexpected. Used during bitmap receive. Setting new bits 547 * requires sending of "out-of-sync" information, though. */ 548 BM_LOCKED_SET_ALLOWED = BM_DONT_CLEAR | BM_IS_LOCKED, 549 550 /* for drbd_bm_write_copy_pages, everything is allowed, 551 * only concurrent bulk operations are locked out. */ 552 BM_LOCKED_CHANGE_ALLOWED = BM_IS_LOCKED, 553 }; 554 555 struct drbd_work_queue { 556 struct list_head q; 557 spinlock_t q_lock; /* to protect the list. */ 558 wait_queue_head_t q_wait; 559 }; 560 561 struct drbd_socket { 562 struct mutex mutex; 563 struct socket *socket; 564 /* this way we get our 565 * send/receive buffers off the stack */ 566 void *sbuf; 567 void *rbuf; 568 }; 569 570 struct drbd_md { 571 u64 md_offset; /* sector offset to 'super' block */ 572 573 u64 la_size_sect; /* last agreed size, unit sectors */ 574 spinlock_t uuid_lock; 575 u64 uuid[UI_SIZE]; 576 u64 device_uuid; 577 u32 flags; 578 u32 md_size_sect; 579 580 s32 al_offset; /* signed relative sector offset to activity log */ 581 s32 bm_offset; /* signed relative sector offset to bitmap */ 582 583 /* cached value of bdev->disk_conf->meta_dev_idx (see below) */ 584 s32 meta_dev_idx; 585 586 /* see al_tr_number_to_on_disk_sector() */ 587 u32 al_stripes; 588 u32 al_stripe_size_4k; 589 u32 al_size_4k; /* cached product of the above */ 590 }; 591 592 struct drbd_backing_dev { 593 struct block_device *backing_bdev; 594 struct block_device *md_bdev; 595 struct drbd_md md; 596 struct disk_conf *disk_conf; /* RCU, for updates: resource->conf_update */ 597 sector_t known_size; /* last known size of that backing device */ 598 }; 599 600 struct drbd_md_io { 601 struct page *page; 602 unsigned long start_jif; /* last call to drbd_md_get_buffer */ 603 unsigned long submit_jif; /* last _drbd_md_sync_page_io() submit */ 604 const char *current_use; 605 atomic_t in_use; 606 unsigned int done; 607 int error; 608 }; 609 610 struct bm_io_work { 611 struct drbd_work w; 612 char *why; 613 enum bm_flag flags; 614 int (*io_fn)(struct drbd_device *device); 615 void (*done)(struct drbd_device *device, int rv); 616 }; 617 618 struct fifo_buffer { 619 unsigned int head_index; 620 unsigned int size; 621 int total; /* sum of all values */ 622 int values[]; 623 }; 624 extern struct fifo_buffer *fifo_alloc(unsigned int fifo_size); 625 626 /* flag bits per connection */ 627 enum { 628 NET_CONGESTED, /* The data socket is congested */ 629 RESOLVE_CONFLICTS, /* Set on one node, cleared on the peer! */ 630 SEND_PING, 631 GOT_PING_ACK, /* set when we receive a ping_ack packet, ping_wait gets woken */ 632 CONN_WD_ST_CHG_REQ, /* A cluster wide state change on the connection is active */ 633 CONN_WD_ST_CHG_OKAY, 634 CONN_WD_ST_CHG_FAIL, 635 CONN_DRY_RUN, /* Expect disconnect after resync handshake. */ 636 CREATE_BARRIER, /* next P_DATA is preceded by a P_BARRIER */ 637 STATE_SENT, /* Do not change state/UUIDs while this is set */ 638 CALLBACK_PENDING, /* Whether we have a call_usermodehelper(, UMH_WAIT_PROC) 639 * pending, from drbd worker context. 640 */ 641 DISCONNECT_SENT, 642 643 DEVICE_WORK_PENDING, /* tell worker that some device has pending work */ 644 }; 645 646 enum which_state { NOW, OLD = NOW, NEW }; 647 648 struct drbd_resource { 649 char *name; 650 #ifdef CONFIG_DEBUG_FS 651 struct dentry *debugfs_res; 652 struct dentry *debugfs_res_volumes; 653 struct dentry *debugfs_res_connections; 654 struct dentry *debugfs_res_in_flight_summary; 655 #endif 656 struct kref kref; 657 struct idr devices; /* volume number to device mapping */ 658 struct list_head connections; 659 struct list_head resources; 660 struct res_opts res_opts; 661 struct mutex conf_update; /* mutex for ready-copy-update of net_conf and disk_conf */ 662 struct mutex adm_mutex; /* mutex to serialize administrative requests */ 663 spinlock_t req_lock; 664 665 unsigned susp:1; /* IO suspended by user */ 666 unsigned susp_nod:1; /* IO suspended because no data */ 667 unsigned susp_fen:1; /* IO suspended because fence peer handler runs */ 668 669 enum write_ordering_e write_ordering; 670 671 cpumask_var_t cpu_mask; 672 }; 673 674 struct drbd_thread_timing_details 675 { 676 unsigned long start_jif; 677 void *cb_addr; 678 const char *caller_fn; 679 unsigned int line; 680 unsigned int cb_nr; 681 }; 682 683 struct drbd_connection { 684 struct list_head connections; 685 struct drbd_resource *resource; 686 #ifdef CONFIG_DEBUG_FS 687 struct dentry *debugfs_conn; 688 struct dentry *debugfs_conn_callback_history; 689 struct dentry *debugfs_conn_oldest_requests; 690 #endif 691 struct kref kref; 692 struct idr peer_devices; /* volume number to peer device mapping */ 693 enum drbd_conns cstate; /* Only C_STANDALONE to C_WF_REPORT_PARAMS */ 694 struct mutex cstate_mutex; /* Protects graceful disconnects */ 695 unsigned int connect_cnt; /* Inc each time a connection is established */ 696 697 unsigned long flags; 698 struct net_conf *net_conf; /* content protected by rcu */ 699 wait_queue_head_t ping_wait; /* Woken upon reception of a ping, and a state change */ 700 701 struct sockaddr_storage my_addr; 702 int my_addr_len; 703 struct sockaddr_storage peer_addr; 704 int peer_addr_len; 705 706 struct drbd_socket data; /* data/barrier/cstate/parameter packets */ 707 struct drbd_socket meta; /* ping/ack (metadata) packets */ 708 int agreed_pro_version; /* actually used protocol version */ 709 u32 agreed_features; 710 unsigned long last_received; /* in jiffies, either socket */ 711 unsigned int ko_count; 712 713 struct list_head transfer_log; /* all requests not yet fully processed */ 714 715 struct crypto_shash *cram_hmac_tfm; 716 struct crypto_shash *integrity_tfm; /* checksums we compute, updates protected by connection->data->mutex */ 717 struct crypto_shash *peer_integrity_tfm; /* checksums we verify, only accessed from receiver thread */ 718 struct crypto_shash *csums_tfm; 719 struct crypto_shash *verify_tfm; 720 void *int_dig_in; 721 void *int_dig_vv; 722 723 /* receiver side */ 724 struct drbd_epoch *current_epoch; 725 spinlock_t epoch_lock; 726 unsigned int epochs; 727 atomic_t current_tle_nr; /* transfer log epoch number */ 728 unsigned current_tle_writes; /* writes seen within this tl epoch */ 729 730 unsigned long last_reconnect_jif; 731 /* empty member on older kernels without blk_start_plug() */ 732 struct blk_plug receiver_plug; 733 struct drbd_thread receiver; 734 struct drbd_thread worker; 735 struct drbd_thread ack_receiver; 736 struct workqueue_struct *ack_sender; 737 738 /* cached pointers, 739 * so we can look up the oldest pending requests more quickly. 740 * protected by resource->req_lock */ 741 struct drbd_request *req_next; /* DRBD 9: todo.req_next */ 742 struct drbd_request *req_ack_pending; 743 struct drbd_request *req_not_net_done; 744 745 /* sender side */ 746 struct drbd_work_queue sender_work; 747 748 #define DRBD_THREAD_DETAILS_HIST 16 749 unsigned int w_cb_nr; /* keeps counting up */ 750 unsigned int r_cb_nr; /* keeps counting up */ 751 struct drbd_thread_timing_details w_timing_details[DRBD_THREAD_DETAILS_HIST]; 752 struct drbd_thread_timing_details r_timing_details[DRBD_THREAD_DETAILS_HIST]; 753 754 struct { 755 unsigned long last_sent_barrier_jif; 756 757 /* whether this sender thread 758 * has processed a single write yet. */ 759 bool seen_any_write_yet; 760 761 /* Which barrier number to send with the next P_BARRIER */ 762 int current_epoch_nr; 763 764 /* how many write requests have been sent 765 * with req->epoch == current_epoch_nr. 766 * If none, no P_BARRIER will be sent. */ 767 unsigned current_epoch_writes; 768 } send; 769 }; 770 771 static inline bool has_net_conf(struct drbd_connection *connection) 772 { 773 bool has_net_conf; 774 775 rcu_read_lock(); 776 has_net_conf = rcu_dereference(connection->net_conf); 777 rcu_read_unlock(); 778 779 return has_net_conf; 780 } 781 782 void __update_timing_details( 783 struct drbd_thread_timing_details *tdp, 784 unsigned int *cb_nr, 785 void *cb, 786 const char *fn, const unsigned int line); 787 788 #define update_worker_timing_details(c, cb) \ 789 __update_timing_details(c->w_timing_details, &c->w_cb_nr, cb, __func__ , __LINE__ ) 790 #define update_receiver_timing_details(c, cb) \ 791 __update_timing_details(c->r_timing_details, &c->r_cb_nr, cb, __func__ , __LINE__ ) 792 793 struct submit_worker { 794 struct workqueue_struct *wq; 795 struct work_struct worker; 796 797 /* protected by ..->resource->req_lock */ 798 struct list_head writes; 799 }; 800 801 struct drbd_peer_device { 802 struct list_head peer_devices; 803 struct drbd_device *device; 804 struct drbd_connection *connection; 805 struct work_struct send_acks_work; 806 #ifdef CONFIG_DEBUG_FS 807 struct dentry *debugfs_peer_dev; 808 #endif 809 }; 810 811 struct drbd_device { 812 struct drbd_resource *resource; 813 struct list_head peer_devices; 814 struct list_head pending_bitmap_io; 815 816 unsigned long flush_jif; 817 #ifdef CONFIG_DEBUG_FS 818 struct dentry *debugfs_minor; 819 struct dentry *debugfs_vol; 820 struct dentry *debugfs_vol_oldest_requests; 821 struct dentry *debugfs_vol_act_log_extents; 822 struct dentry *debugfs_vol_resync_extents; 823 struct dentry *debugfs_vol_data_gen_id; 824 struct dentry *debugfs_vol_ed_gen_id; 825 #endif 826 827 unsigned int vnr; /* volume number within the connection */ 828 unsigned int minor; /* device minor number */ 829 830 struct kref kref; 831 832 /* things that are stored as / read from meta data on disk */ 833 unsigned long flags; 834 835 /* configured by drbdsetup */ 836 struct drbd_backing_dev *ldev __protected_by(local); 837 838 sector_t p_size; /* partner's disk size */ 839 struct request_queue *rq_queue; 840 struct gendisk *vdisk; 841 842 unsigned long last_reattach_jif; 843 struct drbd_work resync_work; 844 struct drbd_work unplug_work; 845 struct timer_list resync_timer; 846 struct timer_list md_sync_timer; 847 struct timer_list start_resync_timer; 848 struct timer_list request_timer; 849 850 /* Used after attach while negotiating new disk state. */ 851 union drbd_state new_state_tmp; 852 853 union drbd_dev_state state; 854 wait_queue_head_t misc_wait; 855 wait_queue_head_t state_wait; /* upon each state change. */ 856 unsigned int send_cnt; 857 unsigned int recv_cnt; 858 unsigned int read_cnt; 859 unsigned int writ_cnt; 860 unsigned int al_writ_cnt; 861 unsigned int bm_writ_cnt; 862 atomic_t ap_bio_cnt; /* Requests we need to complete */ 863 atomic_t ap_actlog_cnt; /* Requests waiting for activity log */ 864 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */ 865 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */ 866 atomic_t unacked_cnt; /* Need to send replies for */ 867 atomic_t local_cnt; /* Waiting for local completion */ 868 atomic_t suspend_cnt; 869 870 /* Interval tree of pending local requests */ 871 struct rb_root read_requests; 872 struct rb_root write_requests; 873 874 /* for statistics and timeouts */ 875 /* [0] read, [1] write */ 876 struct list_head pending_master_completion[2]; 877 struct list_head pending_completion[2]; 878 879 /* use checksums for *this* resync */ 880 bool use_csums; 881 /* blocks to resync in this run [unit BM_BLOCK_SIZE] */ 882 unsigned long rs_total; 883 /* number of resync blocks that failed in this run */ 884 unsigned long rs_failed; 885 /* Syncer's start time [unit jiffies] */ 886 unsigned long rs_start; 887 /* cumulated time in PausedSyncX state [unit jiffies] */ 888 unsigned long rs_paused; 889 /* skipped because csum was equal [unit BM_BLOCK_SIZE] */ 890 unsigned long rs_same_csum; 891 #define DRBD_SYNC_MARKS 8 892 #define DRBD_SYNC_MARK_STEP (3*HZ) 893 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */ 894 unsigned long rs_mark_left[DRBD_SYNC_MARKS]; 895 /* marks's time [unit jiffies] */ 896 unsigned long rs_mark_time[DRBD_SYNC_MARKS]; 897 /* current index into rs_mark_{left,time} */ 898 int rs_last_mark; 899 unsigned long rs_last_bcast; /* [unit jiffies] */ 900 901 /* where does the admin want us to start? (sector) */ 902 sector_t ov_start_sector; 903 sector_t ov_stop_sector; 904 /* where are we now? (sector) */ 905 sector_t ov_position; 906 /* Start sector of out of sync range (to merge printk reporting). */ 907 sector_t ov_last_oos_start; 908 /* size of out-of-sync range in sectors. */ 909 sector_t ov_last_oos_size; 910 unsigned long ov_left; /* in bits */ 911 912 struct drbd_bitmap *bitmap; 913 unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */ 914 915 /* Used to track operations of resync... */ 916 struct lru_cache *resync; 917 /* Number of locked elements in resync LRU */ 918 unsigned int resync_locked; 919 /* resync extent number waiting for application requests */ 920 unsigned int resync_wenr; 921 922 int open_cnt; 923 u64 *p_uuid; 924 925 struct list_head active_ee; /* IO in progress (P_DATA gets written to disk) */ 926 struct list_head sync_ee; /* IO in progress (P_RS_DATA_REPLY gets written to disk) */ 927 struct list_head done_ee; /* need to send P_WRITE_ACK */ 928 struct list_head read_ee; /* [RS]P_DATA_REQUEST being read */ 929 struct list_head net_ee; /* zero-copy network send in progress */ 930 931 int next_barrier_nr; 932 struct list_head resync_reads; 933 atomic_t pp_in_use; /* allocated from page pool */ 934 atomic_t pp_in_use_by_net; /* sendpage()d, still referenced by tcp */ 935 wait_queue_head_t ee_wait; 936 struct drbd_md_io md_io; 937 spinlock_t al_lock; 938 wait_queue_head_t al_wait; 939 struct lru_cache *act_log; /* activity log */ 940 unsigned int al_tr_number; 941 int al_tr_cycle; 942 wait_queue_head_t seq_wait; 943 atomic_t packet_seq; 944 unsigned int peer_seq; 945 spinlock_t peer_seq_lock; 946 unsigned long comm_bm_set; /* communicated number of set bits. */ 947 struct bm_io_work bm_io_work; 948 u64 ed_uuid; /* UUID of the exposed data */ 949 struct mutex own_state_mutex; 950 struct mutex *state_mutex; /* either own_state_mutex or first_peer_device(device)->connection->cstate_mutex */ 951 char congestion_reason; /* Why we where congested... */ 952 atomic_t rs_sect_in; /* for incoming resync data rate, SyncTarget */ 953 atomic_t rs_sect_ev; /* for submitted resync data rate, both */ 954 int rs_last_sect_ev; /* counter to compare with */ 955 int rs_last_events; /* counter of read or write "events" (unit sectors) 956 * on the lower level device when we last looked. */ 957 int c_sync_rate; /* current resync rate after syncer throttle magic */ 958 struct fifo_buffer *rs_plan_s; /* correction values of resync planer (RCU, connection->conn_update) */ 959 int rs_in_flight; /* resync sectors in flight (to proxy, in proxy and from proxy) */ 960 atomic_t ap_in_flight; /* App sectors in flight (waiting for ack) */ 961 unsigned int peer_max_bio_size; 962 unsigned int local_max_bio_size; 963 964 /* any requests that would block in drbd_make_request() 965 * are deferred to this single-threaded work queue */ 966 struct submit_worker submit; 967 }; 968 969 struct drbd_bm_aio_ctx { 970 struct drbd_device *device; 971 struct list_head list; /* on device->pending_bitmap_io */; 972 unsigned long start_jif; 973 atomic_t in_flight; 974 unsigned int done; 975 unsigned flags; 976 #define BM_AIO_COPY_PAGES 1 977 #define BM_AIO_WRITE_HINTED 2 978 #define BM_AIO_WRITE_ALL_PAGES 4 979 #define BM_AIO_READ 8 980 int error; 981 struct kref kref; 982 }; 983 984 struct drbd_config_context { 985 /* assigned from drbd_genlmsghdr */ 986 unsigned int minor; 987 /* assigned from request attributes, if present */ 988 unsigned int volume; 989 #define VOLUME_UNSPECIFIED (-1U) 990 /* pointer into the request skb, 991 * limited lifetime! */ 992 char *resource_name; 993 struct nlattr *my_addr; 994 struct nlattr *peer_addr; 995 996 /* reply buffer */ 997 struct sk_buff *reply_skb; 998 /* pointer into reply buffer */ 999 struct drbd_genlmsghdr *reply_dh; 1000 /* resolved from attributes, if possible */ 1001 struct drbd_device *device; 1002 struct drbd_resource *resource; 1003 struct drbd_connection *connection; 1004 }; 1005 1006 static inline struct drbd_device *minor_to_device(unsigned int minor) 1007 { 1008 return (struct drbd_device *)idr_find(&drbd_devices, minor); 1009 } 1010 1011 static inline struct drbd_peer_device *first_peer_device(struct drbd_device *device) 1012 { 1013 return list_first_entry_or_null(&device->peer_devices, struct drbd_peer_device, peer_devices); 1014 } 1015 1016 static inline struct drbd_peer_device * 1017 conn_peer_device(struct drbd_connection *connection, int volume_number) 1018 { 1019 return idr_find(&connection->peer_devices, volume_number); 1020 } 1021 1022 #define for_each_resource(resource, _resources) \ 1023 list_for_each_entry(resource, _resources, resources) 1024 1025 #define for_each_resource_rcu(resource, _resources) \ 1026 list_for_each_entry_rcu(resource, _resources, resources) 1027 1028 #define for_each_resource_safe(resource, tmp, _resources) \ 1029 list_for_each_entry_safe(resource, tmp, _resources, resources) 1030 1031 #define for_each_connection(connection, resource) \ 1032 list_for_each_entry(connection, &resource->connections, connections) 1033 1034 #define for_each_connection_rcu(connection, resource) \ 1035 list_for_each_entry_rcu(connection, &resource->connections, connections) 1036 1037 #define for_each_connection_safe(connection, tmp, resource) \ 1038 list_for_each_entry_safe(connection, tmp, &resource->connections, connections) 1039 1040 #define for_each_peer_device(peer_device, device) \ 1041 list_for_each_entry(peer_device, &device->peer_devices, peer_devices) 1042 1043 #define for_each_peer_device_rcu(peer_device, device) \ 1044 list_for_each_entry_rcu(peer_device, &device->peer_devices, peer_devices) 1045 1046 #define for_each_peer_device_safe(peer_device, tmp, device) \ 1047 list_for_each_entry_safe(peer_device, tmp, &device->peer_devices, peer_devices) 1048 1049 static inline unsigned int device_to_minor(struct drbd_device *device) 1050 { 1051 return device->minor; 1052 } 1053 1054 /* 1055 * function declarations 1056 *************************/ 1057 1058 /* drbd_main.c */ 1059 1060 enum dds_flags { 1061 DDSF_FORCED = 1, 1062 DDSF_NO_RESYNC = 2, /* Do not run a resync for the new space */ 1063 }; 1064 1065 extern void drbd_init_set_defaults(struct drbd_device *device); 1066 extern int drbd_thread_start(struct drbd_thread *thi); 1067 extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait); 1068 #ifdef CONFIG_SMP 1069 extern void drbd_thread_current_set_cpu(struct drbd_thread *thi); 1070 #else 1071 #define drbd_thread_current_set_cpu(A) ({}) 1072 #endif 1073 extern void tl_release(struct drbd_connection *, unsigned int barrier_nr, 1074 unsigned int set_size); 1075 extern void tl_clear(struct drbd_connection *); 1076 extern void drbd_free_sock(struct drbd_connection *connection); 1077 extern int drbd_send(struct drbd_connection *connection, struct socket *sock, 1078 void *buf, size_t size, unsigned msg_flags); 1079 extern int drbd_send_all(struct drbd_connection *, struct socket *, void *, size_t, 1080 unsigned); 1081 1082 extern int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cmd); 1083 extern int drbd_send_protocol(struct drbd_connection *connection); 1084 extern int drbd_send_uuids(struct drbd_peer_device *); 1085 extern int drbd_send_uuids_skip_initial_sync(struct drbd_peer_device *); 1086 extern void drbd_gen_and_send_sync_uuid(struct drbd_peer_device *); 1087 extern int drbd_send_sizes(struct drbd_peer_device *, int trigger_reply, enum dds_flags flags); 1088 extern int drbd_send_state(struct drbd_peer_device *, union drbd_state s); 1089 extern int drbd_send_current_state(struct drbd_peer_device *); 1090 extern int drbd_send_sync_param(struct drbd_peer_device *); 1091 extern void drbd_send_b_ack(struct drbd_connection *connection, u32 barrier_nr, 1092 u32 set_size); 1093 extern int drbd_send_ack(struct drbd_peer_device *, enum drbd_packet, 1094 struct drbd_peer_request *); 1095 extern void drbd_send_ack_rp(struct drbd_peer_device *, enum drbd_packet, 1096 struct p_block_req *rp); 1097 extern void drbd_send_ack_dp(struct drbd_peer_device *, enum drbd_packet, 1098 struct p_data *dp, int data_size); 1099 extern int drbd_send_ack_ex(struct drbd_peer_device *, enum drbd_packet, 1100 sector_t sector, int blksize, u64 block_id); 1101 extern int drbd_send_out_of_sync(struct drbd_peer_device *, struct drbd_request *); 1102 extern int drbd_send_block(struct drbd_peer_device *, enum drbd_packet, 1103 struct drbd_peer_request *); 1104 extern int drbd_send_dblock(struct drbd_peer_device *, struct drbd_request *req); 1105 extern int drbd_send_drequest(struct drbd_peer_device *, int cmd, 1106 sector_t sector, int size, u64 block_id); 1107 extern int drbd_send_drequest_csum(struct drbd_peer_device *, sector_t sector, 1108 int size, void *digest, int digest_size, 1109 enum drbd_packet cmd); 1110 extern int drbd_send_ov_request(struct drbd_peer_device *, sector_t sector, int size); 1111 1112 extern int drbd_send_bitmap(struct drbd_device *device); 1113 extern void drbd_send_sr_reply(struct drbd_peer_device *, enum drbd_state_rv retcode); 1114 extern void conn_send_sr_reply(struct drbd_connection *connection, enum drbd_state_rv retcode); 1115 extern int drbd_send_rs_deallocated(struct drbd_peer_device *, struct drbd_peer_request *); 1116 extern void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *ldev); 1117 extern void drbd_device_cleanup(struct drbd_device *device); 1118 extern void drbd_print_uuids(struct drbd_device *device, const char *text); 1119 extern void drbd_queue_unplug(struct drbd_device *device); 1120 1121 extern void conn_md_sync(struct drbd_connection *connection); 1122 extern void drbd_md_write(struct drbd_device *device, void *buffer); 1123 extern void drbd_md_sync(struct drbd_device *device); 1124 extern int drbd_md_read(struct drbd_device *device, struct drbd_backing_dev *bdev); 1125 extern void drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); 1126 extern void _drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); 1127 extern void drbd_uuid_new_current(struct drbd_device *device) __must_hold(local); 1128 extern void drbd_uuid_set_bm(struct drbd_device *device, u64 val) __must_hold(local); 1129 extern void drbd_uuid_move_history(struct drbd_device *device) __must_hold(local); 1130 extern void __drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); 1131 extern void drbd_md_set_flag(struct drbd_device *device, int flags) __must_hold(local); 1132 extern void drbd_md_clear_flag(struct drbd_device *device, int flags)__must_hold(local); 1133 extern int drbd_md_test_flag(struct drbd_backing_dev *, int); 1134 extern void drbd_md_mark_dirty(struct drbd_device *device); 1135 extern void drbd_queue_bitmap_io(struct drbd_device *device, 1136 int (*io_fn)(struct drbd_device *), 1137 void (*done)(struct drbd_device *, int), 1138 char *why, enum bm_flag flags); 1139 extern int drbd_bitmap_io(struct drbd_device *device, 1140 int (*io_fn)(struct drbd_device *), 1141 char *why, enum bm_flag flags); 1142 extern int drbd_bitmap_io_from_worker(struct drbd_device *device, 1143 int (*io_fn)(struct drbd_device *), 1144 char *why, enum bm_flag flags); 1145 extern int drbd_bmio_set_n_write(struct drbd_device *device) __must_hold(local); 1146 extern int drbd_bmio_clear_n_write(struct drbd_device *device) __must_hold(local); 1147 1148 /* Meta data layout 1149 * 1150 * We currently have two possible layouts. 1151 * Offsets in (512 byte) sectors. 1152 * external: 1153 * |----------- md_size_sect ------------------| 1154 * [ 4k superblock ][ activity log ][ Bitmap ] 1155 * | al_offset == 8 | 1156 * | bm_offset = al_offset + X | 1157 * ==> bitmap sectors = md_size_sect - bm_offset 1158 * 1159 * Variants: 1160 * old, indexed fixed size meta data: 1161 * 1162 * internal: 1163 * |----------- md_size_sect ------------------| 1164 * [data.....][ Bitmap ][ activity log ][ 4k superblock ][padding*] 1165 * | al_offset < 0 | 1166 * | bm_offset = al_offset - Y | 1167 * ==> bitmap sectors = Y = al_offset - bm_offset 1168 * 1169 * [padding*] are zero or up to 7 unused 512 Byte sectors to the 1170 * end of the device, so that the [4k superblock] will be 4k aligned. 1171 * 1172 * The activity log consists of 4k transaction blocks, 1173 * which are written in a ring-buffer, or striped ring-buffer like fashion, 1174 * which are writtensize used to be fixed 32kB, 1175 * but is about to become configurable. 1176 */ 1177 1178 /* Our old fixed size meta data layout 1179 * allows up to about 3.8TB, so if you want more, 1180 * you need to use the "flexible" meta data format. */ 1181 #define MD_128MB_SECT (128LLU << 11) /* 128 MB, unit sectors */ 1182 #define MD_4kB_SECT 8 1183 #define MD_32kB_SECT 64 1184 1185 /* One activity log extent represents 4M of storage */ 1186 #define AL_EXTENT_SHIFT 22 1187 #define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT) 1188 1189 /* We could make these currently hardcoded constants configurable 1190 * variables at create-md time (or even re-configurable at runtime?). 1191 * Which will require some more changes to the DRBD "super block" 1192 * and attach code. 1193 * 1194 * updates per transaction: 1195 * This many changes to the active set can be logged with one transaction. 1196 * This number is arbitrary. 1197 * context per transaction: 1198 * This many context extent numbers are logged with each transaction. 1199 * This number is resulting from the transaction block size (4k), the layout 1200 * of the transaction header, and the number of updates per transaction. 1201 * See drbd_actlog.c:struct al_transaction_on_disk 1202 * */ 1203 #define AL_UPDATES_PER_TRANSACTION 64 // arbitrary 1204 #define AL_CONTEXT_PER_TRANSACTION 919 // (4096 - 36 - 6*64)/4 1205 1206 #if BITS_PER_LONG == 32 1207 #define LN2_BPL 5 1208 #define cpu_to_lel(A) cpu_to_le32(A) 1209 #define lel_to_cpu(A) le32_to_cpu(A) 1210 #elif BITS_PER_LONG == 64 1211 #define LN2_BPL 6 1212 #define cpu_to_lel(A) cpu_to_le64(A) 1213 #define lel_to_cpu(A) le64_to_cpu(A) 1214 #else 1215 #error "LN2 of BITS_PER_LONG unknown!" 1216 #endif 1217 1218 /* resync bitmap */ 1219 /* 16MB sized 'bitmap extent' to track syncer usage */ 1220 struct bm_extent { 1221 int rs_left; /* number of bits set (out of sync) in this extent. */ 1222 int rs_failed; /* number of failed resync requests in this extent. */ 1223 unsigned long flags; 1224 struct lc_element lce; 1225 }; 1226 1227 #define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */ 1228 #define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */ 1229 #define BME_PRIORITY 2 /* finish resync IO on this extent ASAP! App IO waiting! */ 1230 1231 /* drbd_bitmap.c */ 1232 /* 1233 * We need to store one bit for a block. 1234 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap. 1235 * Bit 0 ==> local node thinks this block is binary identical on both nodes 1236 * Bit 1 ==> local node thinks this block needs to be synced. 1237 */ 1238 1239 #define SLEEP_TIME (HZ/10) 1240 1241 /* We do bitmap IO in units of 4k blocks. 1242 * We also still have a hardcoded 4k per bit relation. */ 1243 #define BM_BLOCK_SHIFT 12 /* 4k per bit */ 1244 #define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT) 1245 /* mostly arbitrarily set the represented size of one bitmap extent, 1246 * aka resync extent, to 16 MiB (which is also 512 Byte worth of bitmap 1247 * at 4k per bit resolution) */ 1248 #define BM_EXT_SHIFT 24 /* 16 MiB per resync extent */ 1249 #define BM_EXT_SIZE (1<<BM_EXT_SHIFT) 1250 1251 #if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12) 1252 #error "HAVE YOU FIXED drbdmeta AS WELL??" 1253 #endif 1254 1255 /* thus many _storage_ sectors are described by one bit */ 1256 #define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9)) 1257 #define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9)) 1258 #define BM_SECT_PER_BIT BM_BIT_TO_SECT(1) 1259 1260 /* bit to represented kilo byte conversion */ 1261 #define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10)) 1262 1263 /* in which _bitmap_ extent (resp. sector) the bit for a certain 1264 * _storage_ sector is located in */ 1265 #define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9)) 1266 #define BM_BIT_TO_EXT(x) ((x) >> (BM_EXT_SHIFT - BM_BLOCK_SHIFT)) 1267 1268 /* first storage sector a bitmap extent corresponds to */ 1269 #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9)) 1270 /* how much _storage_ sectors we have per bitmap extent */ 1271 #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1) 1272 /* how many bits are covered by one bitmap extent (resync extent) */ 1273 #define BM_BITS_PER_EXT (1UL << (BM_EXT_SHIFT - BM_BLOCK_SHIFT)) 1274 1275 #define BM_BLOCKS_PER_BM_EXT_MASK (BM_BITS_PER_EXT - 1) 1276 1277 1278 /* in one sector of the bitmap, we have this many activity_log extents. */ 1279 #define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT)) 1280 1281 /* the extent in "PER_EXTENT" below is an activity log extent 1282 * we need that many (long words/bytes) to store the bitmap 1283 * of one AL_EXTENT_SIZE chunk of storage. 1284 * we can store the bitmap for that many AL_EXTENTS within 1285 * one sector of the _on_disk_ bitmap: 1286 * bit 0 bit 37 bit 38 bit (512*8)-1 1287 * ...|........|........|.. // ..|........| 1288 * sect. 0 `296 `304 ^(512*8*8)-1 1289 * 1290 #define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG ) 1291 #define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128 1292 #define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4 1293 */ 1294 1295 #define DRBD_MAX_SECTORS_32 (0xffffffffLU) 1296 /* we have a certain meta data variant that has a fixed on-disk size of 128 1297 * MiB, of which 4k are our "superblock", and 32k are the fixed size activity 1298 * log, leaving this many sectors for the bitmap. 1299 */ 1300 1301 #define DRBD_MAX_SECTORS_FIXED_BM \ 1302 ((MD_128MB_SECT - MD_32kB_SECT - MD_4kB_SECT) * (1LL<<(BM_EXT_SHIFT-9))) 1303 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_FIXED_BM 1304 /* 16 TB in units of sectors */ 1305 #if BITS_PER_LONG == 32 1306 /* adjust by one page worth of bitmap, 1307 * so we won't wrap around in drbd_bm_find_next_bit. 1308 * you should use 64bit OS for that much storage, anyways. */ 1309 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff) 1310 #else 1311 /* we allow up to 1 PiB now on 64bit architecture with "flexible" meta data */ 1312 #define DRBD_MAX_SECTORS_FLEX (1UL << 51) 1313 /* corresponds to (1UL << 38) bits right now. */ 1314 #endif 1315 1316 /* Estimate max bio size as 256 * PAGE_SIZE, 1317 * so for typical PAGE_SIZE of 4k, that is (1<<20) Byte. 1318 * Since we may live in a mixed-platform cluster, 1319 * we limit us to a platform agnostic constant here for now. 1320 * A followup commit may allow even bigger BIO sizes, 1321 * once we thought that through. */ 1322 #define DRBD_MAX_BIO_SIZE (1U << 20) 1323 #if DRBD_MAX_BIO_SIZE > (BIO_MAX_VECS << PAGE_SHIFT) 1324 #error Architecture not supported: DRBD_MAX_BIO_SIZE > BIO_MAX_SIZE 1325 #endif 1326 #define DRBD_MAX_BIO_SIZE_SAFE (1U << 12) /* Works always = 4k */ 1327 1328 #define DRBD_MAX_SIZE_H80_PACKET (1U << 15) /* Header 80 only allows packets up to 32KiB data */ 1329 #define DRBD_MAX_BIO_SIZE_P95 (1U << 17) /* Protocol 95 to 99 allows bios up to 128KiB */ 1330 1331 /* For now, don't allow more than half of what we can "activate" in one 1332 * activity log transaction to be discarded in one go. We may need to rework 1333 * drbd_al_begin_io() to allow for even larger discard ranges */ 1334 #define DRBD_MAX_BATCH_BIO_SIZE (AL_UPDATES_PER_TRANSACTION/2*AL_EXTENT_SIZE) 1335 #define DRBD_MAX_BBIO_SECTORS (DRBD_MAX_BATCH_BIO_SIZE >> 9) 1336 1337 extern int drbd_bm_init(struct drbd_device *device); 1338 extern int drbd_bm_resize(struct drbd_device *device, sector_t sectors, int set_new_bits); 1339 extern void drbd_bm_cleanup(struct drbd_device *device); 1340 extern void drbd_bm_set_all(struct drbd_device *device); 1341 extern void drbd_bm_clear_all(struct drbd_device *device); 1342 /* set/clear/test only a few bits at a time */ 1343 extern int drbd_bm_set_bits( 1344 struct drbd_device *device, unsigned long s, unsigned long e); 1345 extern int drbd_bm_clear_bits( 1346 struct drbd_device *device, unsigned long s, unsigned long e); 1347 extern int drbd_bm_count_bits( 1348 struct drbd_device *device, const unsigned long s, const unsigned long e); 1349 /* bm_set_bits variant for use while holding drbd_bm_lock, 1350 * may process the whole bitmap in one go */ 1351 extern void _drbd_bm_set_bits(struct drbd_device *device, 1352 const unsigned long s, const unsigned long e); 1353 extern int drbd_bm_test_bit(struct drbd_device *device, unsigned long bitnr); 1354 extern int drbd_bm_e_weight(struct drbd_device *device, unsigned long enr); 1355 extern int drbd_bm_read(struct drbd_device *device) __must_hold(local); 1356 extern void drbd_bm_mark_for_writeout(struct drbd_device *device, int page_nr); 1357 extern int drbd_bm_write(struct drbd_device *device) __must_hold(local); 1358 extern void drbd_bm_reset_al_hints(struct drbd_device *device) __must_hold(local); 1359 extern int drbd_bm_write_hinted(struct drbd_device *device) __must_hold(local); 1360 extern int drbd_bm_write_lazy(struct drbd_device *device, unsigned upper_idx) __must_hold(local); 1361 extern int drbd_bm_write_all(struct drbd_device *device) __must_hold(local); 1362 extern int drbd_bm_write_copy_pages(struct drbd_device *device) __must_hold(local); 1363 extern size_t drbd_bm_words(struct drbd_device *device); 1364 extern unsigned long drbd_bm_bits(struct drbd_device *device); 1365 extern sector_t drbd_bm_capacity(struct drbd_device *device); 1366 1367 #define DRBD_END_OF_BITMAP (~(unsigned long)0) 1368 extern unsigned long drbd_bm_find_next(struct drbd_device *device, unsigned long bm_fo); 1369 /* bm_find_next variants for use while you hold drbd_bm_lock() */ 1370 extern unsigned long _drbd_bm_find_next(struct drbd_device *device, unsigned long bm_fo); 1371 extern unsigned long _drbd_bm_find_next_zero(struct drbd_device *device, unsigned long bm_fo); 1372 extern unsigned long _drbd_bm_total_weight(struct drbd_device *device); 1373 extern unsigned long drbd_bm_total_weight(struct drbd_device *device); 1374 /* for receive_bitmap */ 1375 extern void drbd_bm_merge_lel(struct drbd_device *device, size_t offset, 1376 size_t number, unsigned long *buffer); 1377 /* for _drbd_send_bitmap */ 1378 extern void drbd_bm_get_lel(struct drbd_device *device, size_t offset, 1379 size_t number, unsigned long *buffer); 1380 1381 extern void drbd_bm_lock(struct drbd_device *device, char *why, enum bm_flag flags); 1382 extern void drbd_bm_unlock(struct drbd_device *device); 1383 /* drbd_main.c */ 1384 1385 extern struct kmem_cache *drbd_request_cache; 1386 extern struct kmem_cache *drbd_ee_cache; /* peer requests */ 1387 extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 1388 extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 1389 extern mempool_t drbd_request_mempool; 1390 extern mempool_t drbd_ee_mempool; 1391 1392 /* drbd's page pool, used to buffer data received from the peer, 1393 * or data requested by the peer. 1394 * 1395 * This does not have an emergency reserve. 1396 * 1397 * When allocating from this pool, it first takes pages from the pool. 1398 * Only if the pool is depleted will try to allocate from the system. 1399 * 1400 * The assumption is that pages taken from this pool will be processed, 1401 * and given back, "quickly", and then can be recycled, so we can avoid 1402 * frequent calls to alloc_page(), and still will be able to make progress even 1403 * under memory pressure. 1404 */ 1405 extern struct page *drbd_pp_pool; 1406 extern spinlock_t drbd_pp_lock; 1407 extern int drbd_pp_vacant; 1408 extern wait_queue_head_t drbd_pp_wait; 1409 1410 /* We also need a standard (emergency-reserve backed) page pool 1411 * for meta data IO (activity log, bitmap). 1412 * We can keep it global, as long as it is used as "N pages at a time". 1413 * 128 should be plenty, currently we probably can get away with as few as 1. 1414 */ 1415 #define DRBD_MIN_POOL_PAGES 128 1416 extern mempool_t drbd_md_io_page_pool; 1417 1418 /* We also need to make sure we get a bio 1419 * when we need it for housekeeping purposes */ 1420 extern struct bio_set drbd_md_io_bio_set; 1421 1422 /* And a bio_set for cloning */ 1423 extern struct bio_set drbd_io_bio_set; 1424 1425 extern struct mutex resources_mutex; 1426 1427 extern int conn_lowest_minor(struct drbd_connection *connection); 1428 extern enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsigned int minor); 1429 extern void drbd_destroy_device(struct kref *kref); 1430 extern void drbd_delete_device(struct drbd_device *device); 1431 1432 extern struct drbd_resource *drbd_create_resource(const char *name); 1433 extern void drbd_free_resource(struct drbd_resource *resource); 1434 1435 extern int set_resource_options(struct drbd_resource *resource, struct res_opts *res_opts); 1436 extern struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts); 1437 extern void drbd_destroy_connection(struct kref *kref); 1438 extern struct drbd_connection *conn_get_by_addrs(void *my_addr, int my_addr_len, 1439 void *peer_addr, int peer_addr_len); 1440 extern struct drbd_resource *drbd_find_resource(const char *name); 1441 extern void drbd_destroy_resource(struct kref *kref); 1442 extern void conn_free_crypto(struct drbd_connection *connection); 1443 1444 /* drbd_req */ 1445 extern void do_submit(struct work_struct *ws); 1446 extern void __drbd_make_request(struct drbd_device *, struct bio *); 1447 void drbd_submit_bio(struct bio *bio); 1448 extern int drbd_read_remote(struct drbd_device *device, struct drbd_request *req); 1449 extern int is_valid_ar_handle(struct drbd_request *, sector_t); 1450 1451 1452 /* drbd_nl.c */ 1453 1454 extern struct mutex notification_mutex; 1455 1456 extern void drbd_suspend_io(struct drbd_device *device); 1457 extern void drbd_resume_io(struct drbd_device *device); 1458 extern char *ppsize(char *buf, unsigned long long size); 1459 extern sector_t drbd_new_dev_size(struct drbd_device *, struct drbd_backing_dev *, sector_t, int); 1460 enum determine_dev_size { 1461 DS_ERROR_SHRINK = -3, 1462 DS_ERROR_SPACE_MD = -2, 1463 DS_ERROR = -1, 1464 DS_UNCHANGED = 0, 1465 DS_SHRUNK = 1, 1466 DS_GREW = 2, 1467 DS_GREW_FROM_ZERO = 3, 1468 }; 1469 extern enum determine_dev_size 1470 drbd_determine_dev_size(struct drbd_device *, enum dds_flags, struct resize_parms *) __must_hold(local); 1471 extern void resync_after_online_grow(struct drbd_device *); 1472 extern void drbd_reconsider_queue_parameters(struct drbd_device *device, 1473 struct drbd_backing_dev *bdev, struct o_qlim *o); 1474 extern enum drbd_state_rv drbd_set_role(struct drbd_device *device, 1475 enum drbd_role new_role, 1476 int force); 1477 extern bool conn_try_outdate_peer(struct drbd_connection *connection); 1478 extern void conn_try_outdate_peer_async(struct drbd_connection *connection); 1479 extern enum drbd_peer_state conn_khelper(struct drbd_connection *connection, char *cmd); 1480 extern int drbd_khelper(struct drbd_device *device, char *cmd); 1481 1482 /* drbd_worker.c */ 1483 /* bi_end_io handlers */ 1484 extern void drbd_md_endio(struct bio *bio); 1485 extern void drbd_peer_request_endio(struct bio *bio); 1486 extern void drbd_request_endio(struct bio *bio); 1487 extern int drbd_worker(struct drbd_thread *thi); 1488 enum drbd_ret_code drbd_resync_after_valid(struct drbd_device *device, int o_minor); 1489 void drbd_resync_after_changed(struct drbd_device *device); 1490 extern void drbd_start_resync(struct drbd_device *device, enum drbd_conns side); 1491 extern void resume_next_sg(struct drbd_device *device); 1492 extern void suspend_other_sg(struct drbd_device *device); 1493 extern int drbd_resync_finished(struct drbd_device *device); 1494 /* maybe rather drbd_main.c ? */ 1495 extern void *drbd_md_get_buffer(struct drbd_device *device, const char *intent); 1496 extern void drbd_md_put_buffer(struct drbd_device *device); 1497 extern int drbd_md_sync_page_io(struct drbd_device *device, 1498 struct drbd_backing_dev *bdev, sector_t sector, int op); 1499 extern void drbd_ov_out_of_sync_found(struct drbd_device *, sector_t, int); 1500 extern void wait_until_done_or_force_detached(struct drbd_device *device, 1501 struct drbd_backing_dev *bdev, unsigned int *done); 1502 extern void drbd_rs_controller_reset(struct drbd_device *device); 1503 1504 static inline void ov_out_of_sync_print(struct drbd_device *device) 1505 { 1506 if (device->ov_last_oos_size) { 1507 drbd_err(device, "Out of sync: start=%llu, size=%lu (sectors)\n", 1508 (unsigned long long)device->ov_last_oos_start, 1509 (unsigned long)device->ov_last_oos_size); 1510 } 1511 device->ov_last_oos_size = 0; 1512 } 1513 1514 1515 extern void drbd_csum_bio(struct crypto_shash *, struct bio *, void *); 1516 extern void drbd_csum_ee(struct crypto_shash *, struct drbd_peer_request *, 1517 void *); 1518 /* worker callbacks */ 1519 extern int w_e_end_data_req(struct drbd_work *, int); 1520 extern int w_e_end_rsdata_req(struct drbd_work *, int); 1521 extern int w_e_end_csum_rs_req(struct drbd_work *, int); 1522 extern int w_e_end_ov_reply(struct drbd_work *, int); 1523 extern int w_e_end_ov_req(struct drbd_work *, int); 1524 extern int w_ov_finished(struct drbd_work *, int); 1525 extern int w_resync_timer(struct drbd_work *, int); 1526 extern int w_send_write_hint(struct drbd_work *, int); 1527 extern int w_send_dblock(struct drbd_work *, int); 1528 extern int w_send_read_req(struct drbd_work *, int); 1529 extern int w_e_reissue(struct drbd_work *, int); 1530 extern int w_restart_disk_io(struct drbd_work *, int); 1531 extern int w_send_out_of_sync(struct drbd_work *, int); 1532 extern int w_start_resync(struct drbd_work *, int); 1533 1534 extern void resync_timer_fn(struct timer_list *t); 1535 extern void start_resync_timer_fn(struct timer_list *t); 1536 1537 extern void drbd_endio_write_sec_final(struct drbd_peer_request *peer_req); 1538 1539 /* drbd_receiver.c */ 1540 extern int drbd_issue_discard_or_zero_out(struct drbd_device *device, 1541 sector_t start, unsigned int nr_sectors, int flags); 1542 extern int drbd_receiver(struct drbd_thread *thi); 1543 extern int drbd_ack_receiver(struct drbd_thread *thi); 1544 extern void drbd_send_ping_wf(struct work_struct *ws); 1545 extern void drbd_send_acks_wf(struct work_struct *ws); 1546 extern bool drbd_rs_c_min_rate_throttle(struct drbd_device *device); 1547 extern bool drbd_rs_should_slow_down(struct drbd_device *device, sector_t sector, 1548 bool throttle_if_app_is_waiting); 1549 extern int drbd_submit_peer_request(struct drbd_device *, 1550 struct drbd_peer_request *, const unsigned, 1551 const unsigned, const int); 1552 extern int drbd_free_peer_reqs(struct drbd_device *, struct list_head *); 1553 extern struct drbd_peer_request *drbd_alloc_peer_req(struct drbd_peer_device *, u64, 1554 sector_t, unsigned int, 1555 unsigned int, 1556 gfp_t) __must_hold(local); 1557 extern void __drbd_free_peer_req(struct drbd_device *, struct drbd_peer_request *, 1558 int); 1559 #define drbd_free_peer_req(m,e) __drbd_free_peer_req(m, e, 0) 1560 #define drbd_free_net_peer_req(m,e) __drbd_free_peer_req(m, e, 1) 1561 extern struct page *drbd_alloc_pages(struct drbd_peer_device *, unsigned int, bool); 1562 extern void drbd_set_recv_tcq(struct drbd_device *device, int tcq_enabled); 1563 extern void _drbd_clear_done_ee(struct drbd_device *device, struct list_head *to_be_freed); 1564 extern int drbd_connected(struct drbd_peer_device *); 1565 1566 /* sets the number of 512 byte sectors of our virtual device */ 1567 void drbd_set_my_capacity(struct drbd_device *device, sector_t size); 1568 1569 /* 1570 * used to submit our private bio 1571 */ 1572 static inline void drbd_submit_bio_noacct(struct drbd_device *device, 1573 int fault_type, struct bio *bio) 1574 { 1575 __release(local); 1576 if (!bio->bi_bdev) { 1577 drbd_err(device, "drbd_submit_bio_noacct: bio->bi_bdev == NULL\n"); 1578 bio->bi_status = BLK_STS_IOERR; 1579 bio_endio(bio); 1580 return; 1581 } 1582 1583 if (drbd_insert_fault(device, fault_type)) 1584 bio_io_error(bio); 1585 else 1586 submit_bio_noacct(bio); 1587 } 1588 1589 void drbd_bump_write_ordering(struct drbd_resource *resource, struct drbd_backing_dev *bdev, 1590 enum write_ordering_e wo); 1591 1592 /* drbd_proc.c */ 1593 extern struct proc_dir_entry *drbd_proc; 1594 int drbd_seq_show(struct seq_file *seq, void *v); 1595 1596 /* drbd_actlog.c */ 1597 extern bool drbd_al_begin_io_prepare(struct drbd_device *device, struct drbd_interval *i); 1598 extern int drbd_al_begin_io_nonblock(struct drbd_device *device, struct drbd_interval *i); 1599 extern void drbd_al_begin_io_commit(struct drbd_device *device); 1600 extern bool drbd_al_begin_io_fastpath(struct drbd_device *device, struct drbd_interval *i); 1601 extern void drbd_al_begin_io(struct drbd_device *device, struct drbd_interval *i); 1602 extern void drbd_al_complete_io(struct drbd_device *device, struct drbd_interval *i); 1603 extern void drbd_rs_complete_io(struct drbd_device *device, sector_t sector); 1604 extern int drbd_rs_begin_io(struct drbd_device *device, sector_t sector); 1605 extern int drbd_try_rs_begin_io(struct drbd_device *device, sector_t sector); 1606 extern void drbd_rs_cancel_all(struct drbd_device *device); 1607 extern int drbd_rs_del_all(struct drbd_device *device); 1608 extern void drbd_rs_failed_io(struct drbd_device *device, 1609 sector_t sector, int size); 1610 extern void drbd_advance_rs_marks(struct drbd_device *device, unsigned long still_to_go); 1611 1612 enum update_sync_bits_mode { RECORD_RS_FAILED, SET_OUT_OF_SYNC, SET_IN_SYNC }; 1613 extern int __drbd_change_sync(struct drbd_device *device, sector_t sector, int size, 1614 enum update_sync_bits_mode mode); 1615 #define drbd_set_in_sync(device, sector, size) \ 1616 __drbd_change_sync(device, sector, size, SET_IN_SYNC) 1617 #define drbd_set_out_of_sync(device, sector, size) \ 1618 __drbd_change_sync(device, sector, size, SET_OUT_OF_SYNC) 1619 #define drbd_rs_failed_io(device, sector, size) \ 1620 __drbd_change_sync(device, sector, size, RECORD_RS_FAILED) 1621 extern void drbd_al_shrink(struct drbd_device *device); 1622 extern int drbd_al_initialize(struct drbd_device *, void *); 1623 1624 /* drbd_nl.c */ 1625 /* state info broadcast */ 1626 struct sib_info { 1627 enum drbd_state_info_bcast_reason sib_reason; 1628 union { 1629 struct { 1630 char *helper_name; 1631 unsigned helper_exit_code; 1632 }; 1633 struct { 1634 union drbd_state os; 1635 union drbd_state ns; 1636 }; 1637 }; 1638 }; 1639 void drbd_bcast_event(struct drbd_device *device, const struct sib_info *sib); 1640 1641 extern int notify_resource_state(struct sk_buff *, 1642 unsigned int, 1643 struct drbd_resource *, 1644 struct resource_info *, 1645 enum drbd_notification_type); 1646 extern int notify_device_state(struct sk_buff *, 1647 unsigned int, 1648 struct drbd_device *, 1649 struct device_info *, 1650 enum drbd_notification_type); 1651 extern int notify_connection_state(struct sk_buff *, 1652 unsigned int, 1653 struct drbd_connection *, 1654 struct connection_info *, 1655 enum drbd_notification_type); 1656 extern int notify_peer_device_state(struct sk_buff *, 1657 unsigned int, 1658 struct drbd_peer_device *, 1659 struct peer_device_info *, 1660 enum drbd_notification_type); 1661 extern void notify_helper(enum drbd_notification_type, struct drbd_device *, 1662 struct drbd_connection *, const char *, int); 1663 1664 /* 1665 * inline helper functions 1666 *************************/ 1667 1668 /* see also page_chain_add and friends in drbd_receiver.c */ 1669 static inline struct page *page_chain_next(struct page *page) 1670 { 1671 return (struct page *)page_private(page); 1672 } 1673 #define page_chain_for_each(page) \ 1674 for (; page && ({ prefetch(page_chain_next(page)); 1; }); \ 1675 page = page_chain_next(page)) 1676 #define page_chain_for_each_safe(page, n) \ 1677 for (; page && ({ n = page_chain_next(page); 1; }); page = n) 1678 1679 1680 static inline int drbd_peer_req_has_active_page(struct drbd_peer_request *peer_req) 1681 { 1682 struct page *page = peer_req->pages; 1683 page_chain_for_each(page) { 1684 if (page_count(page) > 1) 1685 return 1; 1686 } 1687 return 0; 1688 } 1689 1690 static inline union drbd_state drbd_read_state(struct drbd_device *device) 1691 { 1692 struct drbd_resource *resource = device->resource; 1693 union drbd_state rv; 1694 1695 rv.i = device->state.i; 1696 rv.susp = resource->susp; 1697 rv.susp_nod = resource->susp_nod; 1698 rv.susp_fen = resource->susp_fen; 1699 1700 return rv; 1701 } 1702 1703 enum drbd_force_detach_flags { 1704 DRBD_READ_ERROR, 1705 DRBD_WRITE_ERROR, 1706 DRBD_META_IO_ERROR, 1707 DRBD_FORCE_DETACH, 1708 }; 1709 1710 #define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__) 1711 static inline void __drbd_chk_io_error_(struct drbd_device *device, 1712 enum drbd_force_detach_flags df, 1713 const char *where) 1714 { 1715 enum drbd_io_error_p ep; 1716 1717 rcu_read_lock(); 1718 ep = rcu_dereference(device->ldev->disk_conf)->on_io_error; 1719 rcu_read_unlock(); 1720 switch (ep) { 1721 case EP_PASS_ON: /* FIXME would this be better named "Ignore"? */ 1722 if (df == DRBD_READ_ERROR || df == DRBD_WRITE_ERROR) { 1723 if (__ratelimit(&drbd_ratelimit_state)) 1724 drbd_err(device, "Local IO failed in %s.\n", where); 1725 if (device->state.disk > D_INCONSISTENT) 1726 _drbd_set_state(_NS(device, disk, D_INCONSISTENT), CS_HARD, NULL); 1727 break; 1728 } 1729 fallthrough; /* for DRBD_META_IO_ERROR or DRBD_FORCE_DETACH */ 1730 case EP_DETACH: 1731 case EP_CALL_HELPER: 1732 /* Remember whether we saw a READ or WRITE error. 1733 * 1734 * Recovery of the affected area for WRITE failure is covered 1735 * by the activity log. 1736 * READ errors may fall outside that area though. Certain READ 1737 * errors can be "healed" by writing good data to the affected 1738 * blocks, which triggers block re-allocation in lower layers. 1739 * 1740 * If we can not write the bitmap after a READ error, 1741 * we may need to trigger a full sync (see w_go_diskless()). 1742 * 1743 * Force-detach is not really an IO error, but rather a 1744 * desperate measure to try to deal with a completely 1745 * unresponsive lower level IO stack. 1746 * Still it should be treated as a WRITE error. 1747 * 1748 * Meta IO error is always WRITE error: 1749 * we read meta data only once during attach, 1750 * which will fail in case of errors. 1751 */ 1752 set_bit(WAS_IO_ERROR, &device->flags); 1753 if (df == DRBD_READ_ERROR) 1754 set_bit(WAS_READ_ERROR, &device->flags); 1755 if (df == DRBD_FORCE_DETACH) 1756 set_bit(FORCE_DETACH, &device->flags); 1757 if (device->state.disk > D_FAILED) { 1758 _drbd_set_state(_NS(device, disk, D_FAILED), CS_HARD, NULL); 1759 drbd_err(device, 1760 "Local IO failed in %s. Detaching...\n", where); 1761 } 1762 break; 1763 } 1764 } 1765 1766 /** 1767 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers 1768 * @device: DRBD device. 1769 * @error: Error code passed to the IO completion callback 1770 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data 1771 * 1772 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED) 1773 */ 1774 #define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__) 1775 static inline void drbd_chk_io_error_(struct drbd_device *device, 1776 int error, enum drbd_force_detach_flags forcedetach, const char *where) 1777 { 1778 if (error) { 1779 unsigned long flags; 1780 spin_lock_irqsave(&device->resource->req_lock, flags); 1781 __drbd_chk_io_error_(device, forcedetach, where); 1782 spin_unlock_irqrestore(&device->resource->req_lock, flags); 1783 } 1784 } 1785 1786 1787 /** 1788 * drbd_md_first_sector() - Returns the first sector number of the meta data area 1789 * @bdev: Meta data block device. 1790 * 1791 * BTW, for internal meta data, this happens to be the maximum capacity 1792 * we could agree upon with our peer node. 1793 */ 1794 static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev) 1795 { 1796 switch (bdev->md.meta_dev_idx) { 1797 case DRBD_MD_INDEX_INTERNAL: 1798 case DRBD_MD_INDEX_FLEX_INT: 1799 return bdev->md.md_offset + bdev->md.bm_offset; 1800 case DRBD_MD_INDEX_FLEX_EXT: 1801 default: 1802 return bdev->md.md_offset; 1803 } 1804 } 1805 1806 /** 1807 * drbd_md_last_sector() - Return the last sector number of the meta data area 1808 * @bdev: Meta data block device. 1809 */ 1810 static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev) 1811 { 1812 switch (bdev->md.meta_dev_idx) { 1813 case DRBD_MD_INDEX_INTERNAL: 1814 case DRBD_MD_INDEX_FLEX_INT: 1815 return bdev->md.md_offset + MD_4kB_SECT -1; 1816 case DRBD_MD_INDEX_FLEX_EXT: 1817 default: 1818 return bdev->md.md_offset + bdev->md.md_size_sect -1; 1819 } 1820 } 1821 1822 /* Returns the number of 512 byte sectors of the device */ 1823 static inline sector_t drbd_get_capacity(struct block_device *bdev) 1824 { 1825 return bdev ? bdev_nr_sectors(bdev) : 0; 1826 } 1827 1828 /** 1829 * drbd_get_max_capacity() - Returns the capacity we announce to out peer 1830 * @bdev: Meta data block device. 1831 * 1832 * returns the capacity we announce to out peer. we clip ourselves at the 1833 * various MAX_SECTORS, because if we don't, current implementation will 1834 * oops sooner or later 1835 */ 1836 static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev) 1837 { 1838 sector_t s; 1839 1840 switch (bdev->md.meta_dev_idx) { 1841 case DRBD_MD_INDEX_INTERNAL: 1842 case DRBD_MD_INDEX_FLEX_INT: 1843 s = drbd_get_capacity(bdev->backing_bdev) 1844 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1845 drbd_md_first_sector(bdev)) 1846 : 0; 1847 break; 1848 case DRBD_MD_INDEX_FLEX_EXT: 1849 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1850 drbd_get_capacity(bdev->backing_bdev)); 1851 /* clip at maximum size the meta device can support */ 1852 s = min_t(sector_t, s, 1853 BM_EXT_TO_SECT(bdev->md.md_size_sect 1854 - bdev->md.bm_offset)); 1855 break; 1856 default: 1857 s = min_t(sector_t, DRBD_MAX_SECTORS, 1858 drbd_get_capacity(bdev->backing_bdev)); 1859 } 1860 return s; 1861 } 1862 1863 /** 1864 * drbd_md_ss() - Return the sector number of our meta data super block 1865 * @bdev: Meta data block device. 1866 */ 1867 static inline sector_t drbd_md_ss(struct drbd_backing_dev *bdev) 1868 { 1869 const int meta_dev_idx = bdev->md.meta_dev_idx; 1870 1871 if (meta_dev_idx == DRBD_MD_INDEX_FLEX_EXT) 1872 return 0; 1873 1874 /* Since drbd08, internal meta data is always "flexible". 1875 * position: last 4k aligned block of 4k size */ 1876 if (meta_dev_idx == DRBD_MD_INDEX_INTERNAL || 1877 meta_dev_idx == DRBD_MD_INDEX_FLEX_INT) 1878 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL) - 8; 1879 1880 /* external, some index; this is the old fixed size layout */ 1881 return MD_128MB_SECT * bdev->md.meta_dev_idx; 1882 } 1883 1884 static inline void 1885 drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 1886 { 1887 unsigned long flags; 1888 spin_lock_irqsave(&q->q_lock, flags); 1889 list_add_tail(&w->list, &q->q); 1890 spin_unlock_irqrestore(&q->q_lock, flags); 1891 wake_up(&q->q_wait); 1892 } 1893 1894 static inline void 1895 drbd_queue_work_if_unqueued(struct drbd_work_queue *q, struct drbd_work *w) 1896 { 1897 unsigned long flags; 1898 spin_lock_irqsave(&q->q_lock, flags); 1899 if (list_empty_careful(&w->list)) 1900 list_add_tail(&w->list, &q->q); 1901 spin_unlock_irqrestore(&q->q_lock, flags); 1902 wake_up(&q->q_wait); 1903 } 1904 1905 static inline void 1906 drbd_device_post_work(struct drbd_device *device, int work_bit) 1907 { 1908 if (!test_and_set_bit(work_bit, &device->flags)) { 1909 struct drbd_connection *connection = 1910 first_peer_device(device)->connection; 1911 struct drbd_work_queue *q = &connection->sender_work; 1912 if (!test_and_set_bit(DEVICE_WORK_PENDING, &connection->flags)) 1913 wake_up(&q->q_wait); 1914 } 1915 } 1916 1917 extern void drbd_flush_workqueue(struct drbd_work_queue *work_queue); 1918 1919 /* To get the ack_receiver out of the blocking network stack, 1920 * so it can change its sk_rcvtimeo from idle- to ping-timeout, 1921 * and send a ping, we need to send a signal. 1922 * Which signal we send is irrelevant. */ 1923 static inline void wake_ack_receiver(struct drbd_connection *connection) 1924 { 1925 struct task_struct *task = connection->ack_receiver.task; 1926 if (task && get_t_state(&connection->ack_receiver) == RUNNING) 1927 send_sig(SIGXCPU, task, 1); 1928 } 1929 1930 static inline void request_ping(struct drbd_connection *connection) 1931 { 1932 set_bit(SEND_PING, &connection->flags); 1933 wake_ack_receiver(connection); 1934 } 1935 1936 extern void *conn_prepare_command(struct drbd_connection *, struct drbd_socket *); 1937 extern void *drbd_prepare_command(struct drbd_peer_device *, struct drbd_socket *); 1938 extern int conn_send_command(struct drbd_connection *, struct drbd_socket *, 1939 enum drbd_packet, unsigned int, void *, 1940 unsigned int); 1941 extern int drbd_send_command(struct drbd_peer_device *, struct drbd_socket *, 1942 enum drbd_packet, unsigned int, void *, 1943 unsigned int); 1944 1945 extern int drbd_send_ping(struct drbd_connection *connection); 1946 extern int drbd_send_ping_ack(struct drbd_connection *connection); 1947 extern int drbd_send_state_req(struct drbd_peer_device *, union drbd_state, union drbd_state); 1948 extern int conn_send_state_req(struct drbd_connection *, union drbd_state, union drbd_state); 1949 1950 static inline void drbd_thread_stop(struct drbd_thread *thi) 1951 { 1952 _drbd_thread_stop(thi, false, true); 1953 } 1954 1955 static inline void drbd_thread_stop_nowait(struct drbd_thread *thi) 1956 { 1957 _drbd_thread_stop(thi, false, false); 1958 } 1959 1960 static inline void drbd_thread_restart_nowait(struct drbd_thread *thi) 1961 { 1962 _drbd_thread_stop(thi, true, false); 1963 } 1964 1965 /* counts how many answer packets packets we expect from our peer, 1966 * for either explicit application requests, 1967 * or implicit barrier packets as necessary. 1968 * increased: 1969 * w_send_barrier 1970 * _req_mod(req, QUEUE_FOR_NET_WRITE or QUEUE_FOR_NET_READ); 1971 * it is much easier and equally valid to count what we queue for the 1972 * worker, even before it actually was queued or send. 1973 * (drbd_make_request_common; recovery path on read io-error) 1974 * decreased: 1975 * got_BarrierAck (respective tl_clear, tl_clear_barrier) 1976 * _req_mod(req, DATA_RECEIVED) 1977 * [from receive_DataReply] 1978 * _req_mod(req, WRITE_ACKED_BY_PEER or RECV_ACKED_BY_PEER or NEG_ACKED) 1979 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)] 1980 * for some reason it is NOT decreased in got_NegAck, 1981 * but in the resulting cleanup code from report_params. 1982 * we should try to remember the reason for that... 1983 * _req_mod(req, SEND_FAILED or SEND_CANCELED) 1984 * _req_mod(req, CONNECTION_LOST_WHILE_PENDING) 1985 * [from tl_clear_barrier] 1986 */ 1987 static inline void inc_ap_pending(struct drbd_device *device) 1988 { 1989 atomic_inc(&device->ap_pending_cnt); 1990 } 1991 1992 #define ERR_IF_CNT_IS_NEGATIVE(which, func, line) \ 1993 if (atomic_read(&device->which) < 0) \ 1994 drbd_err(device, "in %s:%d: " #which " = %d < 0 !\n", \ 1995 func, line, \ 1996 atomic_read(&device->which)) 1997 1998 #define dec_ap_pending(device) _dec_ap_pending(device, __func__, __LINE__) 1999 static inline void _dec_ap_pending(struct drbd_device *device, const char *func, int line) 2000 { 2001 if (atomic_dec_and_test(&device->ap_pending_cnt)) 2002 wake_up(&device->misc_wait); 2003 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt, func, line); 2004 } 2005 2006 /* counts how many resync-related answers we still expect from the peer 2007 * increase decrease 2008 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY) 2009 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK with ID_SYNCER) 2010 * (or P_NEG_ACK with ID_SYNCER) 2011 */ 2012 static inline void inc_rs_pending(struct drbd_device *device) 2013 { 2014 atomic_inc(&device->rs_pending_cnt); 2015 } 2016 2017 #define dec_rs_pending(device) _dec_rs_pending(device, __func__, __LINE__) 2018 static inline void _dec_rs_pending(struct drbd_device *device, const char *func, int line) 2019 { 2020 atomic_dec(&device->rs_pending_cnt); 2021 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt, func, line); 2022 } 2023 2024 /* counts how many answers we still need to send to the peer. 2025 * increased on 2026 * receive_Data unless protocol A; 2027 * we need to send a P_RECV_ACK (proto B) 2028 * or P_WRITE_ACK (proto C) 2029 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK 2030 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA 2031 * receive_Barrier_* we need to send a P_BARRIER_ACK 2032 */ 2033 static inline void inc_unacked(struct drbd_device *device) 2034 { 2035 atomic_inc(&device->unacked_cnt); 2036 } 2037 2038 #define dec_unacked(device) _dec_unacked(device, __func__, __LINE__) 2039 static inline void _dec_unacked(struct drbd_device *device, const char *func, int line) 2040 { 2041 atomic_dec(&device->unacked_cnt); 2042 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line); 2043 } 2044 2045 #define sub_unacked(device, n) _sub_unacked(device, n, __func__, __LINE__) 2046 static inline void _sub_unacked(struct drbd_device *device, int n, const char *func, int line) 2047 { 2048 atomic_sub(n, &device->unacked_cnt); 2049 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line); 2050 } 2051 2052 static inline bool is_sync_target_state(enum drbd_conns connection_state) 2053 { 2054 return connection_state == C_SYNC_TARGET || 2055 connection_state == C_PAUSED_SYNC_T; 2056 } 2057 2058 static inline bool is_sync_source_state(enum drbd_conns connection_state) 2059 { 2060 return connection_state == C_SYNC_SOURCE || 2061 connection_state == C_PAUSED_SYNC_S; 2062 } 2063 2064 static inline bool is_sync_state(enum drbd_conns connection_state) 2065 { 2066 return is_sync_source_state(connection_state) || 2067 is_sync_target_state(connection_state); 2068 } 2069 2070 /** 2071 * get_ldev() - Increase the ref count on device->ldev. Returns 0 if there is no ldev 2072 * @_device: DRBD device. 2073 * @_min_state: Minimum device state required for success. 2074 * 2075 * You have to call put_ldev() when finished working with device->ldev. 2076 */ 2077 #define get_ldev_if_state(_device, _min_state) \ 2078 (_get_ldev_if_state((_device), (_min_state)) ? \ 2079 ({ __acquire(x); true; }) : false) 2080 #define get_ldev(_device) get_ldev_if_state(_device, D_INCONSISTENT) 2081 2082 static inline void put_ldev(struct drbd_device *device) 2083 { 2084 enum drbd_disk_state disk_state = device->state.disk; 2085 /* We must check the state *before* the atomic_dec becomes visible, 2086 * or we have a theoretical race where someone hitting zero, 2087 * while state still D_FAILED, will then see D_DISKLESS in the 2088 * condition below and calling into destroy, where he must not, yet. */ 2089 int i = atomic_dec_return(&device->local_cnt); 2090 2091 /* This may be called from some endio handler, 2092 * so we must not sleep here. */ 2093 2094 __release(local); 2095 D_ASSERT(device, i >= 0); 2096 if (i == 0) { 2097 if (disk_state == D_DISKLESS) 2098 /* even internal references gone, safe to destroy */ 2099 drbd_device_post_work(device, DESTROY_DISK); 2100 if (disk_state == D_FAILED) 2101 /* all application IO references gone. */ 2102 if (!test_and_set_bit(GOING_DISKLESS, &device->flags)) 2103 drbd_device_post_work(device, GO_DISKLESS); 2104 wake_up(&device->misc_wait); 2105 } 2106 } 2107 2108 #ifndef __CHECKER__ 2109 static inline int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins) 2110 { 2111 int io_allowed; 2112 2113 /* never get a reference while D_DISKLESS */ 2114 if (device->state.disk == D_DISKLESS) 2115 return 0; 2116 2117 atomic_inc(&device->local_cnt); 2118 io_allowed = (device->state.disk >= mins); 2119 if (!io_allowed) 2120 put_ldev(device); 2121 return io_allowed; 2122 } 2123 #else 2124 extern int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins); 2125 #endif 2126 2127 /* this throttles on-the-fly application requests 2128 * according to max_buffers settings; 2129 * maybe re-implement using semaphores? */ 2130 static inline int drbd_get_max_buffers(struct drbd_device *device) 2131 { 2132 struct net_conf *nc; 2133 int mxb; 2134 2135 rcu_read_lock(); 2136 nc = rcu_dereference(first_peer_device(device)->connection->net_conf); 2137 mxb = nc ? nc->max_buffers : 1000000; /* arbitrary limit on open requests */ 2138 rcu_read_unlock(); 2139 2140 return mxb; 2141 } 2142 2143 static inline int drbd_state_is_stable(struct drbd_device *device) 2144 { 2145 union drbd_dev_state s = device->state; 2146 2147 /* DO NOT add a default clause, we want the compiler to warn us 2148 * for any newly introduced state we may have forgotten to add here */ 2149 2150 switch ((enum drbd_conns)s.conn) { 2151 /* new io only accepted when there is no connection, ... */ 2152 case C_STANDALONE: 2153 case C_WF_CONNECTION: 2154 /* ... or there is a well established connection. */ 2155 case C_CONNECTED: 2156 case C_SYNC_SOURCE: 2157 case C_SYNC_TARGET: 2158 case C_VERIFY_S: 2159 case C_VERIFY_T: 2160 case C_PAUSED_SYNC_S: 2161 case C_PAUSED_SYNC_T: 2162 case C_AHEAD: 2163 case C_BEHIND: 2164 /* transitional states, IO allowed */ 2165 case C_DISCONNECTING: 2166 case C_UNCONNECTED: 2167 case C_TIMEOUT: 2168 case C_BROKEN_PIPE: 2169 case C_NETWORK_FAILURE: 2170 case C_PROTOCOL_ERROR: 2171 case C_TEAR_DOWN: 2172 case C_WF_REPORT_PARAMS: 2173 case C_STARTING_SYNC_S: 2174 case C_STARTING_SYNC_T: 2175 break; 2176 2177 /* Allow IO in BM exchange states with new protocols */ 2178 case C_WF_BITMAP_S: 2179 if (first_peer_device(device)->connection->agreed_pro_version < 96) 2180 return 0; 2181 break; 2182 2183 /* no new io accepted in these states */ 2184 case C_WF_BITMAP_T: 2185 case C_WF_SYNC_UUID: 2186 case C_MASK: 2187 /* not "stable" */ 2188 return 0; 2189 } 2190 2191 switch ((enum drbd_disk_state)s.disk) { 2192 case D_DISKLESS: 2193 case D_INCONSISTENT: 2194 case D_OUTDATED: 2195 case D_CONSISTENT: 2196 case D_UP_TO_DATE: 2197 case D_FAILED: 2198 /* disk state is stable as well. */ 2199 break; 2200 2201 /* no new io accepted during transitional states */ 2202 case D_ATTACHING: 2203 case D_NEGOTIATING: 2204 case D_UNKNOWN: 2205 case D_MASK: 2206 /* not "stable" */ 2207 return 0; 2208 } 2209 2210 return 1; 2211 } 2212 2213 static inline int drbd_suspended(struct drbd_device *device) 2214 { 2215 struct drbd_resource *resource = device->resource; 2216 2217 return resource->susp || resource->susp_fen || resource->susp_nod; 2218 } 2219 2220 static inline bool may_inc_ap_bio(struct drbd_device *device) 2221 { 2222 int mxb = drbd_get_max_buffers(device); 2223 2224 if (drbd_suspended(device)) 2225 return false; 2226 if (atomic_read(&device->suspend_cnt)) 2227 return false; 2228 2229 /* to avoid potential deadlock or bitmap corruption, 2230 * in various places, we only allow new application io 2231 * to start during "stable" states. */ 2232 2233 /* no new io accepted when attaching or detaching the disk */ 2234 if (!drbd_state_is_stable(device)) 2235 return false; 2236 2237 /* since some older kernels don't have atomic_add_unless, 2238 * and we are within the spinlock anyways, we have this workaround. */ 2239 if (atomic_read(&device->ap_bio_cnt) > mxb) 2240 return false; 2241 if (test_bit(BITMAP_IO, &device->flags)) 2242 return false; 2243 return true; 2244 } 2245 2246 static inline bool inc_ap_bio_cond(struct drbd_device *device) 2247 { 2248 bool rv = false; 2249 2250 spin_lock_irq(&device->resource->req_lock); 2251 rv = may_inc_ap_bio(device); 2252 if (rv) 2253 atomic_inc(&device->ap_bio_cnt); 2254 spin_unlock_irq(&device->resource->req_lock); 2255 2256 return rv; 2257 } 2258 2259 static inline void inc_ap_bio(struct drbd_device *device) 2260 { 2261 /* we wait here 2262 * as long as the device is suspended 2263 * until the bitmap is no longer on the fly during connection 2264 * handshake as long as we would exceed the max_buffer limit. 2265 * 2266 * to avoid races with the reconnect code, 2267 * we need to atomic_inc within the spinlock. */ 2268 2269 wait_event(device->misc_wait, inc_ap_bio_cond(device)); 2270 } 2271 2272 static inline void dec_ap_bio(struct drbd_device *device) 2273 { 2274 int mxb = drbd_get_max_buffers(device); 2275 int ap_bio = atomic_dec_return(&device->ap_bio_cnt); 2276 2277 D_ASSERT(device, ap_bio >= 0); 2278 2279 if (ap_bio == 0 && test_bit(BITMAP_IO, &device->flags)) { 2280 if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags)) 2281 drbd_queue_work(&first_peer_device(device)-> 2282 connection->sender_work, 2283 &device->bm_io_work.w); 2284 } 2285 2286 /* this currently does wake_up for every dec_ap_bio! 2287 * maybe rather introduce some type of hysteresis? 2288 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */ 2289 if (ap_bio < mxb) 2290 wake_up(&device->misc_wait); 2291 } 2292 2293 static inline bool verify_can_do_stop_sector(struct drbd_device *device) 2294 { 2295 return first_peer_device(device)->connection->agreed_pro_version >= 97 && 2296 first_peer_device(device)->connection->agreed_pro_version != 100; 2297 } 2298 2299 static inline int drbd_set_ed_uuid(struct drbd_device *device, u64 val) 2300 { 2301 int changed = device->ed_uuid != val; 2302 device->ed_uuid = val; 2303 return changed; 2304 } 2305 2306 static inline int drbd_queue_order_type(struct drbd_device *device) 2307 { 2308 /* sorry, we currently have no working implementation 2309 * of distributed TCQ stuff */ 2310 #ifndef QUEUE_ORDERED_NONE 2311 #define QUEUE_ORDERED_NONE 0 2312 #endif 2313 return QUEUE_ORDERED_NONE; 2314 } 2315 2316 static inline struct drbd_connection *first_connection(struct drbd_resource *resource) 2317 { 2318 return list_first_entry_or_null(&resource->connections, 2319 struct drbd_connection, connections); 2320 } 2321 2322 #endif 2323