1 /* 2 drbd_int.h 3 4 This file is part of DRBD by Philipp Reisner and Lars Ellenberg. 5 6 Copyright (C) 2001-2008, LINBIT Information Technologies GmbH. 7 Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>. 8 Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>. 9 10 drbd is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License as published by 12 the Free Software Foundation; either version 2, or (at your option) 13 any later version. 14 15 drbd is distributed in the hope that it will be useful, 16 but WITHOUT ANY WARRANTY; without even the implied warranty of 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 GNU General Public License for more details. 19 20 You should have received a copy of the GNU General Public License 21 along with drbd; see the file COPYING. If not, write to 22 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 23 24 */ 25 26 #ifndef _DRBD_INT_H 27 #define _DRBD_INT_H 28 29 #include <linux/compiler.h> 30 #include <linux/types.h> 31 #include <linux/version.h> 32 #include <linux/list.h> 33 #include <linux/sched.h> 34 #include <linux/bitops.h> 35 #include <linux/slab.h> 36 #include <linux/crypto.h> 37 #include <linux/ratelimit.h> 38 #include <linux/tcp.h> 39 #include <linux/mutex.h> 40 #include <linux/major.h> 41 #include <linux/blkdev.h> 42 #include <linux/genhd.h> 43 #include <net/tcp.h> 44 #include <linux/lru_cache.h> 45 46 #ifdef __CHECKER__ 47 # define __protected_by(x) __attribute__((require_context(x,1,999,"rdwr"))) 48 # define __protected_read_by(x) __attribute__((require_context(x,1,999,"read"))) 49 # define __protected_write_by(x) __attribute__((require_context(x,1,999,"write"))) 50 # define __must_hold(x) __attribute__((context(x,1,1), require_context(x,1,999,"call"))) 51 #else 52 # define __protected_by(x) 53 # define __protected_read_by(x) 54 # define __protected_write_by(x) 55 # define __must_hold(x) 56 #endif 57 58 #define __no_warn(lock, stmt) do { __acquire(lock); stmt; __release(lock); } while (0) 59 60 /* module parameter, defined in drbd_main.c */ 61 extern unsigned int minor_count; 62 extern int disable_sendpage; 63 extern int allow_oos; 64 extern unsigned int cn_idx; 65 66 #ifdef CONFIG_DRBD_FAULT_INJECTION 67 extern int enable_faults; 68 extern int fault_rate; 69 extern int fault_devs; 70 #endif 71 72 extern char usermode_helper[]; 73 74 75 #ifndef TRUE 76 #define TRUE 1 77 #endif 78 #ifndef FALSE 79 #define FALSE 0 80 #endif 81 82 /* I don't remember why XCPU ... 83 * This is used to wake the asender, 84 * and to interrupt sending the sending task 85 * on disconnect. 86 */ 87 #define DRBD_SIG SIGXCPU 88 89 /* This is used to stop/restart our threads. 90 * Cannot use SIGTERM nor SIGKILL, since these 91 * are sent out by init on runlevel changes 92 * I choose SIGHUP for now. 93 */ 94 #define DRBD_SIGKILL SIGHUP 95 96 /* All EEs on the free list should have ID_VACANT (== 0) 97 * freshly allocated EEs get !ID_VACANT (== 1) 98 * so if it says "cannot dereference null pointer at address 0x00000001", 99 * it is most likely one of these :( */ 100 101 #define ID_IN_SYNC (4711ULL) 102 #define ID_OUT_OF_SYNC (4712ULL) 103 104 #define ID_SYNCER (-1ULL) 105 #define ID_VACANT 0 106 #define is_syncer_block_id(id) ((id) == ID_SYNCER) 107 108 struct drbd_conf; 109 110 111 /* to shorten dev_warn(DEV, "msg"); and relatives statements */ 112 #define DEV (disk_to_dev(mdev->vdisk)) 113 114 #define D_ASSERT(exp) if (!(exp)) \ 115 dev_err(DEV, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__) 116 117 #define ERR_IF(exp) if (({ \ 118 int _b = (exp) != 0; \ 119 if (_b) dev_err(DEV, "%s: (%s) in %s:%d\n", \ 120 __func__, #exp, __FILE__, __LINE__); \ 121 _b; \ 122 })) 123 124 /* Defines to control fault insertion */ 125 enum { 126 DRBD_FAULT_MD_WR = 0, /* meta data write */ 127 DRBD_FAULT_MD_RD = 1, /* read */ 128 DRBD_FAULT_RS_WR = 2, /* resync */ 129 DRBD_FAULT_RS_RD = 3, 130 DRBD_FAULT_DT_WR = 4, /* data */ 131 DRBD_FAULT_DT_RD = 5, 132 DRBD_FAULT_DT_RA = 6, /* data read ahead */ 133 DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */ 134 DRBD_FAULT_AL_EE = 8, /* alloc ee */ 135 136 DRBD_FAULT_MAX, 137 }; 138 139 #ifdef CONFIG_DRBD_FAULT_INJECTION 140 extern unsigned int 141 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type); 142 static inline int 143 drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) { 144 return fault_rate && 145 (enable_faults & (1<<type)) && 146 _drbd_insert_fault(mdev, type); 147 } 148 #define FAULT_ACTIVE(_m, _t) (drbd_insert_fault((_m), (_t))) 149 150 #else 151 #define FAULT_ACTIVE(_m, _t) (0) 152 #endif 153 154 /* integer division, round _UP_ to the next integer */ 155 #define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0)) 156 /* usual integer division */ 157 #define div_floor(A, B) ((A)/(B)) 158 159 /* drbd_meta-data.c (still in drbd_main.c) */ 160 /* 4th incarnation of the disk layout. */ 161 #define DRBD_MD_MAGIC (DRBD_MAGIC+4) 162 163 extern struct drbd_conf **minor_table; 164 extern struct ratelimit_state drbd_ratelimit_state; 165 166 /* on the wire */ 167 enum drbd_packets { 168 /* receiver (data socket) */ 169 P_DATA = 0x00, 170 P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */ 171 P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */ 172 P_BARRIER = 0x03, 173 P_BITMAP = 0x04, 174 P_BECOME_SYNC_TARGET = 0x05, 175 P_BECOME_SYNC_SOURCE = 0x06, 176 P_UNPLUG_REMOTE = 0x07, /* Used at various times to hint the peer */ 177 P_DATA_REQUEST = 0x08, /* Used to ask for a data block */ 178 P_RS_DATA_REQUEST = 0x09, /* Used to ask for a data block for resync */ 179 P_SYNC_PARAM = 0x0a, 180 P_PROTOCOL = 0x0b, 181 P_UUIDS = 0x0c, 182 P_SIZES = 0x0d, 183 P_STATE = 0x0e, 184 P_SYNC_UUID = 0x0f, 185 P_AUTH_CHALLENGE = 0x10, 186 P_AUTH_RESPONSE = 0x11, 187 P_STATE_CHG_REQ = 0x12, 188 189 /* asender (meta socket */ 190 P_PING = 0x13, 191 P_PING_ACK = 0x14, 192 P_RECV_ACK = 0x15, /* Used in protocol B */ 193 P_WRITE_ACK = 0x16, /* Used in protocol C */ 194 P_RS_WRITE_ACK = 0x17, /* Is a P_WRITE_ACK, additionally call set_in_sync(). */ 195 P_DISCARD_ACK = 0x18, /* Used in proto C, two-primaries conflict detection */ 196 P_NEG_ACK = 0x19, /* Sent if local disk is unusable */ 197 P_NEG_DREPLY = 0x1a, /* Local disk is broken... */ 198 P_NEG_RS_DREPLY = 0x1b, /* Local disk is broken... */ 199 P_BARRIER_ACK = 0x1c, 200 P_STATE_CHG_REPLY = 0x1d, 201 202 /* "new" commands, no longer fitting into the ordering scheme above */ 203 204 P_OV_REQUEST = 0x1e, /* data socket */ 205 P_OV_REPLY = 0x1f, 206 P_OV_RESULT = 0x20, /* meta socket */ 207 P_CSUM_RS_REQUEST = 0x21, /* data socket */ 208 P_RS_IS_IN_SYNC = 0x22, /* meta socket */ 209 P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */ 210 P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */ 211 212 P_MAX_CMD = 0x25, 213 P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */ 214 P_MAX_OPT_CMD = 0x101, 215 216 /* special command ids for handshake */ 217 218 P_HAND_SHAKE_M = 0xfff1, /* First Packet on the MetaSock */ 219 P_HAND_SHAKE_S = 0xfff2, /* First Packet on the Socket */ 220 221 P_HAND_SHAKE = 0xfffe /* FIXED for the next century! */ 222 }; 223 224 static inline const char *cmdname(enum drbd_packets cmd) 225 { 226 /* THINK may need to become several global tables 227 * when we want to support more than 228 * one PRO_VERSION */ 229 static const char *cmdnames[] = { 230 [P_DATA] = "Data", 231 [P_DATA_REPLY] = "DataReply", 232 [P_RS_DATA_REPLY] = "RSDataReply", 233 [P_BARRIER] = "Barrier", 234 [P_BITMAP] = "ReportBitMap", 235 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget", 236 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource", 237 [P_UNPLUG_REMOTE] = "UnplugRemote", 238 [P_DATA_REQUEST] = "DataRequest", 239 [P_RS_DATA_REQUEST] = "RSDataRequest", 240 [P_SYNC_PARAM] = "SyncParam", 241 [P_SYNC_PARAM89] = "SyncParam89", 242 [P_PROTOCOL] = "ReportProtocol", 243 [P_UUIDS] = "ReportUUIDs", 244 [P_SIZES] = "ReportSizes", 245 [P_STATE] = "ReportState", 246 [P_SYNC_UUID] = "ReportSyncUUID", 247 [P_AUTH_CHALLENGE] = "AuthChallenge", 248 [P_AUTH_RESPONSE] = "AuthResponse", 249 [P_PING] = "Ping", 250 [P_PING_ACK] = "PingAck", 251 [P_RECV_ACK] = "RecvAck", 252 [P_WRITE_ACK] = "WriteAck", 253 [P_RS_WRITE_ACK] = "RSWriteAck", 254 [P_DISCARD_ACK] = "DiscardAck", 255 [P_NEG_ACK] = "NegAck", 256 [P_NEG_DREPLY] = "NegDReply", 257 [P_NEG_RS_DREPLY] = "NegRSDReply", 258 [P_BARRIER_ACK] = "BarrierAck", 259 [P_STATE_CHG_REQ] = "StateChgRequest", 260 [P_STATE_CHG_REPLY] = "StateChgReply", 261 [P_OV_REQUEST] = "OVRequest", 262 [P_OV_REPLY] = "OVReply", 263 [P_OV_RESULT] = "OVResult", 264 [P_CSUM_RS_REQUEST] = "CsumRSRequest", 265 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync", 266 [P_COMPRESSED_BITMAP] = "CBitmap", 267 [P_MAX_CMD] = NULL, 268 }; 269 270 if (cmd == P_HAND_SHAKE_M) 271 return "HandShakeM"; 272 if (cmd == P_HAND_SHAKE_S) 273 return "HandShakeS"; 274 if (cmd == P_HAND_SHAKE) 275 return "HandShake"; 276 if (cmd >= P_MAX_CMD) 277 return "Unknown"; 278 return cmdnames[cmd]; 279 } 280 281 /* for sending/receiving the bitmap, 282 * possibly in some encoding scheme */ 283 struct bm_xfer_ctx { 284 /* "const" 285 * stores total bits and long words 286 * of the bitmap, so we don't need to 287 * call the accessor functions over and again. */ 288 unsigned long bm_bits; 289 unsigned long bm_words; 290 /* during xfer, current position within the bitmap */ 291 unsigned long bit_offset; 292 unsigned long word_offset; 293 294 /* statistics; index: (h->command == P_BITMAP) */ 295 unsigned packets[2]; 296 unsigned bytes[2]; 297 }; 298 299 extern void INFO_bm_xfer_stats(struct drbd_conf *mdev, 300 const char *direction, struct bm_xfer_ctx *c); 301 302 static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c) 303 { 304 /* word_offset counts "native long words" (32 or 64 bit), 305 * aligned at 64 bit. 306 * Encoded packet may end at an unaligned bit offset. 307 * In case a fallback clear text packet is transmitted in 308 * between, we adjust this offset back to the last 64bit 309 * aligned "native long word", which makes coding and decoding 310 * the plain text bitmap much more convenient. */ 311 #if BITS_PER_LONG == 64 312 c->word_offset = c->bit_offset >> 6; 313 #elif BITS_PER_LONG == 32 314 c->word_offset = c->bit_offset >> 5; 315 c->word_offset &= ~(1UL); 316 #else 317 # error "unsupported BITS_PER_LONG" 318 #endif 319 } 320 321 #ifndef __packed 322 #define __packed __attribute__((packed)) 323 #endif 324 325 /* This is the layout for a packet on the wire. 326 * The byteorder is the network byte order. 327 * (except block_id and barrier fields. 328 * these are pointers to local structs 329 * and have no relevance for the partner, 330 * which just echoes them as received.) 331 * 332 * NOTE that the payload starts at a long aligned offset, 333 * regardless of 32 or 64 bit arch! 334 */ 335 struct p_header { 336 u32 magic; 337 u16 command; 338 u16 length; /* bytes of data after this header */ 339 u8 payload[0]; 340 } __packed; 341 /* 8 bytes. packet FIXED for the next century! */ 342 343 /* 344 * short commands, packets without payload, plain p_header: 345 * P_PING 346 * P_PING_ACK 347 * P_BECOME_SYNC_TARGET 348 * P_BECOME_SYNC_SOURCE 349 * P_UNPLUG_REMOTE 350 */ 351 352 /* 353 * commands with out-of-struct payload: 354 * P_BITMAP (no additional fields) 355 * P_DATA, P_DATA_REPLY (see p_data) 356 * P_COMPRESSED_BITMAP (see receive_compressed_bitmap) 357 */ 358 359 /* these defines must not be changed without changing the protocol version */ 360 #define DP_HARDBARRIER 1 361 #define DP_RW_SYNC 2 362 #define DP_MAY_SET_IN_SYNC 4 363 364 struct p_data { 365 struct p_header head; 366 u64 sector; /* 64 bits sector number */ 367 u64 block_id; /* to identify the request in protocol B&C */ 368 u32 seq_num; 369 u32 dp_flags; 370 } __packed; 371 372 /* 373 * commands which share a struct: 374 * p_block_ack: 375 * P_RECV_ACK (proto B), P_WRITE_ACK (proto C), 376 * P_DISCARD_ACK (proto C, two-primaries conflict detection) 377 * p_block_req: 378 * P_DATA_REQUEST, P_RS_DATA_REQUEST 379 */ 380 struct p_block_ack { 381 struct p_header head; 382 u64 sector; 383 u64 block_id; 384 u32 blksize; 385 u32 seq_num; 386 } __packed; 387 388 389 struct p_block_req { 390 struct p_header head; 391 u64 sector; 392 u64 block_id; 393 u32 blksize; 394 u32 pad; /* to multiple of 8 Byte */ 395 } __packed; 396 397 /* 398 * commands with their own struct for additional fields: 399 * P_HAND_SHAKE 400 * P_BARRIER 401 * P_BARRIER_ACK 402 * P_SYNC_PARAM 403 * ReportParams 404 */ 405 406 struct p_handshake { 407 struct p_header head; /* 8 bytes */ 408 u32 protocol_min; 409 u32 feature_flags; 410 u32 protocol_max; 411 412 /* should be more than enough for future enhancements 413 * for now, feature_flags and the reserverd array shall be zero. 414 */ 415 416 u32 _pad; 417 u64 reserverd[7]; 418 } __packed; 419 /* 80 bytes, FIXED for the next century */ 420 421 struct p_barrier { 422 struct p_header head; 423 u32 barrier; /* barrier number _handle_ only */ 424 u32 pad; /* to multiple of 8 Byte */ 425 } __packed; 426 427 struct p_barrier_ack { 428 struct p_header head; 429 u32 barrier; 430 u32 set_size; 431 } __packed; 432 433 struct p_rs_param { 434 struct p_header head; 435 u32 rate; 436 437 /* Since protocol version 88 and higher. */ 438 char verify_alg[0]; 439 } __packed; 440 441 struct p_rs_param_89 { 442 struct p_header head; 443 u32 rate; 444 /* protocol version 89: */ 445 char verify_alg[SHARED_SECRET_MAX]; 446 char csums_alg[SHARED_SECRET_MAX]; 447 } __packed; 448 449 enum drbd_conn_flags { 450 CF_WANT_LOSE = 1, 451 CF_DRY_RUN = 2, 452 }; 453 454 struct p_protocol { 455 struct p_header head; 456 u32 protocol; 457 u32 after_sb_0p; 458 u32 after_sb_1p; 459 u32 after_sb_2p; 460 u32 conn_flags; 461 u32 two_primaries; 462 463 /* Since protocol version 87 and higher. */ 464 char integrity_alg[0]; 465 466 } __packed; 467 468 struct p_uuids { 469 struct p_header head; 470 u64 uuid[UI_EXTENDED_SIZE]; 471 } __packed; 472 473 struct p_rs_uuid { 474 struct p_header head; 475 u64 uuid; 476 } __packed; 477 478 struct p_sizes { 479 struct p_header head; 480 u64 d_size; /* size of disk */ 481 u64 u_size; /* user requested size */ 482 u64 c_size; /* current exported size */ 483 u32 max_segment_size; /* Maximal size of a BIO */ 484 u32 queue_order_type; 485 } __packed; 486 487 struct p_state { 488 struct p_header head; 489 u32 state; 490 } __packed; 491 492 struct p_req_state { 493 struct p_header head; 494 u32 mask; 495 u32 val; 496 } __packed; 497 498 struct p_req_state_reply { 499 struct p_header head; 500 u32 retcode; 501 } __packed; 502 503 struct p_drbd06_param { 504 u64 size; 505 u32 state; 506 u32 blksize; 507 u32 protocol; 508 u32 version; 509 u32 gen_cnt[5]; 510 u32 bit_map_gen[5]; 511 } __packed; 512 513 struct p_discard { 514 struct p_header head; 515 u64 block_id; 516 u32 seq_num; 517 u32 pad; 518 } __packed; 519 520 /* Valid values for the encoding field. 521 * Bump proto version when changing this. */ 522 enum drbd_bitmap_code { 523 /* RLE_VLI_Bytes = 0, 524 * and other bit variants had been defined during 525 * algorithm evaluation. */ 526 RLE_VLI_Bits = 2, 527 }; 528 529 struct p_compressed_bm { 530 struct p_header head; 531 /* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code 532 * (encoding & 0x80): polarity (set/unset) of first runlength 533 * ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits 534 * used to pad up to head.length bytes 535 */ 536 u8 encoding; 537 538 u8 code[0]; 539 } __packed; 540 541 /* DCBP: Drbd Compressed Bitmap Packet ... */ 542 static inline enum drbd_bitmap_code 543 DCBP_get_code(struct p_compressed_bm *p) 544 { 545 return (enum drbd_bitmap_code)(p->encoding & 0x0f); 546 } 547 548 static inline void 549 DCBP_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code) 550 { 551 BUG_ON(code & ~0xf); 552 p->encoding = (p->encoding & ~0xf) | code; 553 } 554 555 static inline int 556 DCBP_get_start(struct p_compressed_bm *p) 557 { 558 return (p->encoding & 0x80) != 0; 559 } 560 561 static inline void 562 DCBP_set_start(struct p_compressed_bm *p, int set) 563 { 564 p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0); 565 } 566 567 static inline int 568 DCBP_get_pad_bits(struct p_compressed_bm *p) 569 { 570 return (p->encoding >> 4) & 0x7; 571 } 572 573 static inline void 574 DCBP_set_pad_bits(struct p_compressed_bm *p, int n) 575 { 576 BUG_ON(n & ~0x7); 577 p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4); 578 } 579 580 /* one bitmap packet, including the p_header, 581 * should fit within one _architecture independend_ page. 582 * so we need to use the fixed size 4KiB page size 583 * most architechtures have used for a long time. 584 */ 585 #define BM_PACKET_PAYLOAD_BYTES (4096 - sizeof(struct p_header)) 586 #define BM_PACKET_WORDS (BM_PACKET_PAYLOAD_BYTES/sizeof(long)) 587 #define BM_PACKET_VLI_BYTES_MAX (4096 - sizeof(struct p_compressed_bm)) 588 #if (PAGE_SIZE < 4096) 589 /* drbd_send_bitmap / receive_bitmap would break horribly */ 590 #error "PAGE_SIZE too small" 591 #endif 592 593 union p_polymorph { 594 struct p_header header; 595 struct p_handshake handshake; 596 struct p_data data; 597 struct p_block_ack block_ack; 598 struct p_barrier barrier; 599 struct p_barrier_ack barrier_ack; 600 struct p_rs_param_89 rs_param_89; 601 struct p_protocol protocol; 602 struct p_sizes sizes; 603 struct p_uuids uuids; 604 struct p_state state; 605 struct p_req_state req_state; 606 struct p_req_state_reply req_state_reply; 607 struct p_block_req block_req; 608 } __packed; 609 610 /**********************************************************************/ 611 enum drbd_thread_state { 612 None, 613 Running, 614 Exiting, 615 Restarting 616 }; 617 618 struct drbd_thread { 619 spinlock_t t_lock; 620 struct task_struct *task; 621 struct completion stop; 622 enum drbd_thread_state t_state; 623 int (*function) (struct drbd_thread *); 624 struct drbd_conf *mdev; 625 int reset_cpu_mask; 626 }; 627 628 static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi) 629 { 630 /* THINK testing the t_state seems to be uncritical in all cases 631 * (but thread_{start,stop}), so we can read it *without* the lock. 632 * --lge */ 633 634 smp_rmb(); 635 return thi->t_state; 636 } 637 638 639 /* 640 * Having this as the first member of a struct provides sort of "inheritance". 641 * "derived" structs can be "drbd_queue_work()"ed. 642 * The callback should know and cast back to the descendant struct. 643 * drbd_request and drbd_epoch_entry are descendants of drbd_work. 644 */ 645 struct drbd_work; 646 typedef int (*drbd_work_cb)(struct drbd_conf *, struct drbd_work *, int cancel); 647 struct drbd_work { 648 struct list_head list; 649 drbd_work_cb cb; 650 }; 651 652 struct drbd_tl_epoch; 653 struct drbd_request { 654 struct drbd_work w; 655 struct drbd_conf *mdev; 656 657 /* if local IO is not allowed, will be NULL. 658 * if local IO _is_ allowed, holds the locally submitted bio clone, 659 * or, after local IO completion, the ERR_PTR(error). 660 * see drbd_endio_pri(). */ 661 struct bio *private_bio; 662 663 struct hlist_node colision; 664 sector_t sector; 665 unsigned int size; 666 unsigned int epoch; /* barrier_nr */ 667 668 /* barrier_nr: used to check on "completion" whether this req was in 669 * the current epoch, and we therefore have to close it, 670 * starting a new epoch... 671 */ 672 673 /* up to here, the struct layout is identical to drbd_epoch_entry; 674 * we might be able to use that to our advantage... */ 675 676 struct list_head tl_requests; /* ring list in the transfer log */ 677 struct bio *master_bio; /* master bio pointer */ 678 unsigned long rq_state; /* see comments above _req_mod() */ 679 int seq_num; 680 unsigned long start_time; 681 }; 682 683 struct drbd_tl_epoch { 684 struct drbd_work w; 685 struct list_head requests; /* requests before */ 686 struct drbd_tl_epoch *next; /* pointer to the next barrier */ 687 unsigned int br_number; /* the barriers identifier. */ 688 int n_req; /* number of requests attached before this barrier */ 689 }; 690 691 struct drbd_request; 692 693 /* These Tl_epoch_entries may be in one of 6 lists: 694 active_ee .. data packet being written 695 sync_ee .. syncer block being written 696 done_ee .. block written, need to send P_WRITE_ACK 697 read_ee .. [RS]P_DATA_REQUEST being read 698 */ 699 700 struct drbd_epoch { 701 struct list_head list; 702 unsigned int barrier_nr; 703 atomic_t epoch_size; /* increased on every request added. */ 704 atomic_t active; /* increased on every req. added, and dec on every finished. */ 705 unsigned long flags; 706 }; 707 708 /* drbd_epoch flag bits */ 709 enum { 710 DE_BARRIER_IN_NEXT_EPOCH_ISSUED, 711 DE_BARRIER_IN_NEXT_EPOCH_DONE, 712 DE_CONTAINS_A_BARRIER, 713 DE_HAVE_BARRIER_NUMBER, 714 DE_IS_FINISHING, 715 }; 716 717 enum epoch_event { 718 EV_PUT, 719 EV_GOT_BARRIER_NR, 720 EV_BARRIER_DONE, 721 EV_BECAME_LAST, 722 EV_CLEANUP = 32, /* used as flag */ 723 }; 724 725 struct drbd_epoch_entry { 726 struct drbd_work w; 727 struct drbd_conf *mdev; 728 struct bio *private_bio; 729 struct hlist_node colision; 730 sector_t sector; 731 unsigned int size; 732 struct drbd_epoch *epoch; 733 734 /* up to here, the struct layout is identical to drbd_request; 735 * we might be able to use that to our advantage... */ 736 737 unsigned int flags; 738 u64 block_id; 739 }; 740 741 struct drbd_wq_barrier { 742 struct drbd_work w; 743 struct completion done; 744 }; 745 746 struct digest_info { 747 int digest_size; 748 void *digest; 749 }; 750 751 /* ee flag bits */ 752 enum { 753 __EE_CALL_AL_COMPLETE_IO, 754 __EE_CONFLICT_PENDING, 755 __EE_MAY_SET_IN_SYNC, 756 __EE_IS_BARRIER, 757 }; 758 #define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO) 759 #define EE_CONFLICT_PENDING (1<<__EE_CONFLICT_PENDING) 760 #define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC) 761 #define EE_IS_BARRIER (1<<__EE_IS_BARRIER) 762 763 /* global flag bits */ 764 enum { 765 CREATE_BARRIER, /* next P_DATA is preceeded by a P_BARRIER */ 766 SIGNAL_ASENDER, /* whether asender wants to be interrupted */ 767 SEND_PING, /* whether asender should send a ping asap */ 768 769 STOP_SYNC_TIMER, /* tell timer to cancel itself */ 770 UNPLUG_QUEUED, /* only relevant with kernel 2.4 */ 771 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */ 772 MD_DIRTY, /* current uuids and flags not yet on disk */ 773 DISCARD_CONCURRENT, /* Set on one node, cleared on the peer! */ 774 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */ 775 CLUSTER_ST_CHANGE, /* Cluster wide state change going on... */ 776 CL_ST_CHG_SUCCESS, 777 CL_ST_CHG_FAIL, 778 CRASHED_PRIMARY, /* This node was a crashed primary. 779 * Gets cleared when the state.conn 780 * goes into C_CONNECTED state. */ 781 WRITE_BM_AFTER_RESYNC, /* A kmalloc() during resync failed */ 782 NO_BARRIER_SUPP, /* underlying block device doesn't implement barriers */ 783 CONSIDER_RESYNC, 784 785 MD_NO_BARRIER, /* meta data device does not support barriers, 786 so don't even try */ 787 SUSPEND_IO, /* suspend application io */ 788 BITMAP_IO, /* suspend application io; 789 once no more io in flight, start bitmap io */ 790 BITMAP_IO_QUEUED, /* Started bitmap IO */ 791 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */ 792 NET_CONGESTED, /* The data socket is congested */ 793 794 CONFIG_PENDING, /* serialization of (re)configuration requests. 795 * if set, also prevents the device from dying */ 796 DEVICE_DYING, /* device became unconfigured, 797 * but worker thread is still handling the cleanup. 798 * reconfiguring (nl_disk_conf, nl_net_conf) is dissalowed, 799 * while this is set. */ 800 RESIZE_PENDING, /* Size change detected locally, waiting for the response from 801 * the peer, if it changed there as well. */ 802 CONN_DRY_RUN, /* Expect disconnect after resync handshake. */ 803 GOT_PING_ACK, /* set when we receive a ping_ack packet, misc wait gets woken */ 804 }; 805 806 struct drbd_bitmap; /* opaque for drbd_conf */ 807 808 /* TODO sort members for performance 809 * MAYBE group them further */ 810 811 /* THINK maybe we actually want to use the default "event/%s" worker threads 812 * or similar in linux 2.6, which uses per cpu data and threads. 813 * 814 * To be general, this might need a spin_lock member. 815 * For now, please use the mdev->req_lock to protect list_head, 816 * see drbd_queue_work below. 817 */ 818 struct drbd_work_queue { 819 struct list_head q; 820 struct semaphore s; /* producers up it, worker down()s it */ 821 spinlock_t q_lock; /* to protect the list. */ 822 }; 823 824 struct drbd_socket { 825 struct drbd_work_queue work; 826 struct mutex mutex; 827 struct socket *socket; 828 /* this way we get our 829 * send/receive buffers off the stack */ 830 union p_polymorph sbuf; 831 union p_polymorph rbuf; 832 }; 833 834 struct drbd_md { 835 u64 md_offset; /* sector offset to 'super' block */ 836 837 u64 la_size_sect; /* last agreed size, unit sectors */ 838 u64 uuid[UI_SIZE]; 839 u64 device_uuid; 840 u32 flags; 841 u32 md_size_sect; 842 843 s32 al_offset; /* signed relative sector offset to al area */ 844 s32 bm_offset; /* signed relative sector offset to bitmap */ 845 846 /* u32 al_nr_extents; important for restoring the AL 847 * is stored into sync_conf.al_extents, which in turn 848 * gets applied to act_log->nr_elements 849 */ 850 }; 851 852 /* for sync_conf and other types... */ 853 #define NL_PACKET(name, number, fields) struct name { fields }; 854 #define NL_INTEGER(pn,pr,member) int member; 855 #define NL_INT64(pn,pr,member) __u64 member; 856 #define NL_BIT(pn,pr,member) unsigned member:1; 857 #define NL_STRING(pn,pr,member,len) unsigned char member[len]; int member ## _len; 858 #include "linux/drbd_nl.h" 859 860 struct drbd_backing_dev { 861 struct block_device *backing_bdev; 862 struct block_device *md_bdev; 863 struct file *lo_file; 864 struct file *md_file; 865 struct drbd_md md; 866 struct disk_conf dc; /* The user provided config... */ 867 sector_t known_size; /* last known size of that backing device */ 868 }; 869 870 struct drbd_md_io { 871 struct drbd_conf *mdev; 872 struct completion event; 873 int error; 874 }; 875 876 struct bm_io_work { 877 struct drbd_work w; 878 char *why; 879 int (*io_fn)(struct drbd_conf *mdev); 880 void (*done)(struct drbd_conf *mdev, int rv); 881 }; 882 883 enum write_ordering_e { 884 WO_none, 885 WO_drain_io, 886 WO_bdev_flush, 887 WO_bio_barrier 888 }; 889 890 struct drbd_conf { 891 /* things that are stored as / read from meta data on disk */ 892 unsigned long flags; 893 894 /* configured by drbdsetup */ 895 struct net_conf *net_conf; /* protected by get_net_conf() and put_net_conf() */ 896 struct syncer_conf sync_conf; 897 struct drbd_backing_dev *ldev __protected_by(local); 898 899 sector_t p_size; /* partner's disk size */ 900 struct request_queue *rq_queue; 901 struct block_device *this_bdev; 902 struct gendisk *vdisk; 903 904 struct drbd_socket data; /* data/barrier/cstate/parameter packets */ 905 struct drbd_socket meta; /* ping/ack (metadata) packets */ 906 int agreed_pro_version; /* actually used protocol version */ 907 unsigned long last_received; /* in jiffies, either socket */ 908 unsigned int ko_count; 909 struct drbd_work resync_work, 910 unplug_work, 911 md_sync_work; 912 struct timer_list resync_timer; 913 struct timer_list md_sync_timer; 914 915 /* Used after attach while negotiating new disk state. */ 916 union drbd_state new_state_tmp; 917 918 union drbd_state state; 919 wait_queue_head_t misc_wait; 920 wait_queue_head_t state_wait; /* upon each state change. */ 921 unsigned int send_cnt; 922 unsigned int recv_cnt; 923 unsigned int read_cnt; 924 unsigned int writ_cnt; 925 unsigned int al_writ_cnt; 926 unsigned int bm_writ_cnt; 927 atomic_t ap_bio_cnt; /* Requests we need to complete */ 928 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */ 929 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */ 930 atomic_t unacked_cnt; /* Need to send replys for */ 931 atomic_t local_cnt; /* Waiting for local completion */ 932 atomic_t net_cnt; /* Users of net_conf */ 933 spinlock_t req_lock; 934 struct drbd_tl_epoch *unused_spare_tle; /* for pre-allocation */ 935 struct drbd_tl_epoch *newest_tle; 936 struct drbd_tl_epoch *oldest_tle; 937 struct list_head out_of_sequence_requests; 938 struct hlist_head *tl_hash; 939 unsigned int tl_hash_s; 940 941 /* blocks to sync in this run [unit BM_BLOCK_SIZE] */ 942 unsigned long rs_total; 943 /* number of sync IOs that failed in this run */ 944 unsigned long rs_failed; 945 /* Syncer's start time [unit jiffies] */ 946 unsigned long rs_start; 947 /* cumulated time in PausedSyncX state [unit jiffies] */ 948 unsigned long rs_paused; 949 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */ 950 unsigned long rs_mark_left; 951 /* marks's time [unit jiffies] */ 952 unsigned long rs_mark_time; 953 /* skipped because csum was equeal [unit BM_BLOCK_SIZE] */ 954 unsigned long rs_same_csum; 955 956 /* where does the admin want us to start? (sector) */ 957 sector_t ov_start_sector; 958 /* where are we now? (sector) */ 959 sector_t ov_position; 960 /* Start sector of out of sync range (to merge printk reporting). */ 961 sector_t ov_last_oos_start; 962 /* size of out-of-sync range in sectors. */ 963 sector_t ov_last_oos_size; 964 unsigned long ov_left; /* in bits */ 965 struct crypto_hash *csums_tfm; 966 struct crypto_hash *verify_tfm; 967 968 struct drbd_thread receiver; 969 struct drbd_thread worker; 970 struct drbd_thread asender; 971 struct drbd_bitmap *bitmap; 972 unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */ 973 974 /* Used to track operations of resync... */ 975 struct lru_cache *resync; 976 /* Number of locked elements in resync LRU */ 977 unsigned int resync_locked; 978 /* resync extent number waiting for application requests */ 979 unsigned int resync_wenr; 980 981 int open_cnt; 982 u64 *p_uuid; 983 struct drbd_epoch *current_epoch; 984 spinlock_t epoch_lock; 985 unsigned int epochs; 986 enum write_ordering_e write_ordering; 987 struct list_head active_ee; /* IO in progress */ 988 struct list_head sync_ee; /* IO in progress */ 989 struct list_head done_ee; /* send ack */ 990 struct list_head read_ee; /* IO in progress */ 991 struct list_head net_ee; /* zero-copy network send in progress */ 992 struct hlist_head *ee_hash; /* is proteced by req_lock! */ 993 unsigned int ee_hash_s; 994 995 /* this one is protected by ee_lock, single thread */ 996 struct drbd_epoch_entry *last_write_w_barrier; 997 998 int next_barrier_nr; 999 struct hlist_head *app_reads_hash; /* is proteced by req_lock */ 1000 struct list_head resync_reads; 1001 atomic_t pp_in_use; 1002 wait_queue_head_t ee_wait; 1003 struct page *md_io_page; /* one page buffer for md_io */ 1004 struct page *md_io_tmpp; /* for logical_block_size != 512 */ 1005 struct mutex md_io_mutex; /* protects the md_io_buffer */ 1006 spinlock_t al_lock; 1007 wait_queue_head_t al_wait; 1008 struct lru_cache *act_log; /* activity log */ 1009 unsigned int al_tr_number; 1010 int al_tr_cycle; 1011 int al_tr_pos; /* position of the next transaction in the journal */ 1012 struct crypto_hash *cram_hmac_tfm; 1013 struct crypto_hash *integrity_w_tfm; /* to be used by the worker thread */ 1014 struct crypto_hash *integrity_r_tfm; /* to be used by the receiver thread */ 1015 void *int_dig_out; 1016 void *int_dig_in; 1017 void *int_dig_vv; 1018 wait_queue_head_t seq_wait; 1019 atomic_t packet_seq; 1020 unsigned int peer_seq; 1021 spinlock_t peer_seq_lock; 1022 unsigned int minor; 1023 unsigned long comm_bm_set; /* communicated number of set bits. */ 1024 cpumask_var_t cpu_mask; 1025 struct bm_io_work bm_io_work; 1026 u64 ed_uuid; /* UUID of the exposed data */ 1027 struct mutex state_mutex; 1028 char congestion_reason; /* Why we where congested... */ 1029 }; 1030 1031 static inline struct drbd_conf *minor_to_mdev(unsigned int minor) 1032 { 1033 struct drbd_conf *mdev; 1034 1035 mdev = minor < minor_count ? minor_table[minor] : NULL; 1036 1037 return mdev; 1038 } 1039 1040 static inline unsigned int mdev_to_minor(struct drbd_conf *mdev) 1041 { 1042 return mdev->minor; 1043 } 1044 1045 /* returns 1 if it was successfull, 1046 * returns 0 if there was no data socket. 1047 * so wherever you are going to use the data.socket, e.g. do 1048 * if (!drbd_get_data_sock(mdev)) 1049 * return 0; 1050 * CODE(); 1051 * drbd_put_data_sock(mdev); 1052 */ 1053 static inline int drbd_get_data_sock(struct drbd_conf *mdev) 1054 { 1055 mutex_lock(&mdev->data.mutex); 1056 /* drbd_disconnect() could have called drbd_free_sock() 1057 * while we were waiting in down()... */ 1058 if (unlikely(mdev->data.socket == NULL)) { 1059 mutex_unlock(&mdev->data.mutex); 1060 return 0; 1061 } 1062 return 1; 1063 } 1064 1065 static inline void drbd_put_data_sock(struct drbd_conf *mdev) 1066 { 1067 mutex_unlock(&mdev->data.mutex); 1068 } 1069 1070 /* 1071 * function declarations 1072 *************************/ 1073 1074 /* drbd_main.c */ 1075 1076 enum chg_state_flags { 1077 CS_HARD = 1, 1078 CS_VERBOSE = 2, 1079 CS_WAIT_COMPLETE = 4, 1080 CS_SERIALIZE = 8, 1081 CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE, 1082 }; 1083 1084 extern void drbd_init_set_defaults(struct drbd_conf *mdev); 1085 extern int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f, 1086 union drbd_state mask, union drbd_state val); 1087 extern void drbd_force_state(struct drbd_conf *, union drbd_state, 1088 union drbd_state); 1089 extern int _drbd_request_state(struct drbd_conf *, union drbd_state, 1090 union drbd_state, enum chg_state_flags); 1091 extern int __drbd_set_state(struct drbd_conf *, union drbd_state, 1092 enum chg_state_flags, struct completion *done); 1093 extern void print_st_err(struct drbd_conf *, union drbd_state, 1094 union drbd_state, int); 1095 extern int drbd_thread_start(struct drbd_thread *thi); 1096 extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait); 1097 #ifdef CONFIG_SMP 1098 extern void drbd_thread_current_set_cpu(struct drbd_conf *mdev); 1099 extern void drbd_calc_cpu_mask(struct drbd_conf *mdev); 1100 #else 1101 #define drbd_thread_current_set_cpu(A) ({}) 1102 #define drbd_calc_cpu_mask(A) ({}) 1103 #endif 1104 extern void drbd_free_resources(struct drbd_conf *mdev); 1105 extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr, 1106 unsigned int set_size); 1107 extern void tl_clear(struct drbd_conf *mdev); 1108 extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *); 1109 extern void drbd_free_sock(struct drbd_conf *mdev); 1110 extern int drbd_send(struct drbd_conf *mdev, struct socket *sock, 1111 void *buf, size_t size, unsigned msg_flags); 1112 extern int drbd_send_protocol(struct drbd_conf *mdev); 1113 extern int drbd_send_uuids(struct drbd_conf *mdev); 1114 extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev); 1115 extern int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val); 1116 extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply); 1117 extern int _drbd_send_state(struct drbd_conf *mdev); 1118 extern int drbd_send_state(struct drbd_conf *mdev); 1119 extern int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock, 1120 enum drbd_packets cmd, struct p_header *h, 1121 size_t size, unsigned msg_flags); 1122 #define USE_DATA_SOCKET 1 1123 #define USE_META_SOCKET 0 1124 extern int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket, 1125 enum drbd_packets cmd, struct p_header *h, 1126 size_t size); 1127 extern int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, 1128 char *data, size_t size); 1129 extern int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc); 1130 extern int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, 1131 u32 set_size); 1132 extern int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd, 1133 struct drbd_epoch_entry *e); 1134 extern int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd, 1135 struct p_block_req *rp); 1136 extern int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd, 1137 struct p_data *dp); 1138 extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd, 1139 sector_t sector, int blksize, u64 block_id); 1140 extern int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd, 1141 struct drbd_epoch_entry *e); 1142 extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req); 1143 extern int _drbd_send_barrier(struct drbd_conf *mdev, 1144 struct drbd_tl_epoch *barrier); 1145 extern int drbd_send_drequest(struct drbd_conf *mdev, int cmd, 1146 sector_t sector, int size, u64 block_id); 1147 extern int drbd_send_drequest_csum(struct drbd_conf *mdev, 1148 sector_t sector,int size, 1149 void *digest, int digest_size, 1150 enum drbd_packets cmd); 1151 extern int drbd_send_ov_request(struct drbd_conf *mdev,sector_t sector,int size); 1152 1153 extern int drbd_send_bitmap(struct drbd_conf *mdev); 1154 extern int _drbd_send_bitmap(struct drbd_conf *mdev); 1155 extern int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode); 1156 extern void drbd_free_bc(struct drbd_backing_dev *ldev); 1157 extern void drbd_mdev_cleanup(struct drbd_conf *mdev); 1158 1159 /* drbd_meta-data.c (still in drbd_main.c) */ 1160 extern void drbd_md_sync(struct drbd_conf *mdev); 1161 extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev); 1162 /* maybe define them below as inline? */ 1163 extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1164 extern void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1165 extern void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1166 extern void _drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1167 extern void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local); 1168 extern void drbd_md_set_flag(struct drbd_conf *mdev, int flags) __must_hold(local); 1169 extern void drbd_md_clear_flag(struct drbd_conf *mdev, int flags)__must_hold(local); 1170 extern int drbd_md_test_flag(struct drbd_backing_dev *, int); 1171 extern void drbd_md_mark_dirty(struct drbd_conf *mdev); 1172 extern void drbd_queue_bitmap_io(struct drbd_conf *mdev, 1173 int (*io_fn)(struct drbd_conf *), 1174 void (*done)(struct drbd_conf *, int), 1175 char *why); 1176 extern int drbd_bmio_set_n_write(struct drbd_conf *mdev); 1177 extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev); 1178 extern int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why); 1179 1180 1181 /* Meta data layout 1182 We reserve a 128MB Block (4k aligned) 1183 * either at the end of the backing device 1184 * or on a separate meta data device. */ 1185 1186 #define MD_RESERVED_SECT (128LU << 11) /* 128 MB, unit sectors */ 1187 /* The following numbers are sectors */ 1188 #define MD_AL_OFFSET 8 /* 8 Sectors after start of meta area */ 1189 #define MD_AL_MAX_SIZE 64 /* = 32 kb LOG ~ 3776 extents ~ 14 GB Storage */ 1190 /* Allows up to about 3.8TB */ 1191 #define MD_BM_OFFSET (MD_AL_OFFSET + MD_AL_MAX_SIZE) 1192 1193 /* Since the smalles IO unit is usually 512 byte */ 1194 #define MD_SECTOR_SHIFT 9 1195 #define MD_SECTOR_SIZE (1<<MD_SECTOR_SHIFT) 1196 1197 /* activity log */ 1198 #define AL_EXTENTS_PT ((MD_SECTOR_SIZE-12)/8-1) /* 61 ; Extents per 512B sector */ 1199 #define AL_EXTENT_SHIFT 22 /* One extent represents 4M Storage */ 1200 #define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT) 1201 1202 #if BITS_PER_LONG == 32 1203 #define LN2_BPL 5 1204 #define cpu_to_lel(A) cpu_to_le32(A) 1205 #define lel_to_cpu(A) le32_to_cpu(A) 1206 #elif BITS_PER_LONG == 64 1207 #define LN2_BPL 6 1208 #define cpu_to_lel(A) cpu_to_le64(A) 1209 #define lel_to_cpu(A) le64_to_cpu(A) 1210 #else 1211 #error "LN2 of BITS_PER_LONG unknown!" 1212 #endif 1213 1214 /* resync bitmap */ 1215 /* 16MB sized 'bitmap extent' to track syncer usage */ 1216 struct bm_extent { 1217 int rs_left; /* number of bits set (out of sync) in this extent. */ 1218 int rs_failed; /* number of failed resync requests in this extent. */ 1219 unsigned long flags; 1220 struct lc_element lce; 1221 }; 1222 1223 #define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */ 1224 #define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */ 1225 1226 /* drbd_bitmap.c */ 1227 /* 1228 * We need to store one bit for a block. 1229 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap. 1230 * Bit 0 ==> local node thinks this block is binary identical on both nodes 1231 * Bit 1 ==> local node thinks this block needs to be synced. 1232 */ 1233 1234 #define BM_BLOCK_SHIFT 12 /* 4k per bit */ 1235 #define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT) 1236 /* (9+3) : 512 bytes @ 8 bits; representing 16M storage 1237 * per sector of on disk bitmap */ 1238 #define BM_EXT_SHIFT (BM_BLOCK_SHIFT + MD_SECTOR_SHIFT + 3) /* = 24 */ 1239 #define BM_EXT_SIZE (1<<BM_EXT_SHIFT) 1240 1241 #if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12) 1242 #error "HAVE YOU FIXED drbdmeta AS WELL??" 1243 #endif 1244 1245 /* thus many _storage_ sectors are described by one bit */ 1246 #define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9)) 1247 #define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9)) 1248 #define BM_SECT_PER_BIT BM_BIT_TO_SECT(1) 1249 1250 /* bit to represented kilo byte conversion */ 1251 #define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10)) 1252 1253 /* in which _bitmap_ extent (resp. sector) the bit for a certain 1254 * _storage_ sector is located in */ 1255 #define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9)) 1256 1257 /* how much _storage_ sectors we have per bitmap sector */ 1258 #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9)) 1259 #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1) 1260 1261 /* in one sector of the bitmap, we have this many activity_log extents. */ 1262 #define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT)) 1263 #define BM_WORDS_PER_AL_EXT (1 << (AL_EXTENT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL)) 1264 1265 #define BM_BLOCKS_PER_BM_EXT_B (BM_EXT_SHIFT - BM_BLOCK_SHIFT) 1266 #define BM_BLOCKS_PER_BM_EXT_MASK ((1<<BM_BLOCKS_PER_BM_EXT_B) - 1) 1267 1268 /* the extent in "PER_EXTENT" below is an activity log extent 1269 * we need that many (long words/bytes) to store the bitmap 1270 * of one AL_EXTENT_SIZE chunk of storage. 1271 * we can store the bitmap for that many AL_EXTENTS within 1272 * one sector of the _on_disk_ bitmap: 1273 * bit 0 bit 37 bit 38 bit (512*8)-1 1274 * ...|........|........|.. // ..|........| 1275 * sect. 0 `296 `304 ^(512*8*8)-1 1276 * 1277 #define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG ) 1278 #define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128 1279 #define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4 1280 */ 1281 1282 #define DRBD_MAX_SECTORS_32 (0xffffffffLU) 1283 #define DRBD_MAX_SECTORS_BM \ 1284 ((MD_RESERVED_SECT - MD_BM_OFFSET) * (1LL<<(BM_EXT_SHIFT-9))) 1285 #if DRBD_MAX_SECTORS_BM < DRBD_MAX_SECTORS_32 1286 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1287 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_BM 1288 #elif !defined(CONFIG_LBDAF) && BITS_PER_LONG == 32 1289 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_32 1290 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_32 1291 #else 1292 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1293 /* 16 TB in units of sectors */ 1294 #if BITS_PER_LONG == 32 1295 /* adjust by one page worth of bitmap, 1296 * so we won't wrap around in drbd_bm_find_next_bit. 1297 * you should use 64bit OS for that much storage, anyways. */ 1298 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff) 1299 #else 1300 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0x1LU << 32) 1301 #endif 1302 #endif 1303 1304 /* Sector shift value for the "hash" functions of tl_hash and ee_hash tables. 1305 * With a value of 6 all IO in one 32K block make it to the same slot of the 1306 * hash table. */ 1307 #define HT_SHIFT 6 1308 #define DRBD_MAX_SEGMENT_SIZE (1U<<(9+HT_SHIFT)) 1309 1310 /* Number of elements in the app_reads_hash */ 1311 #define APP_R_HSIZE 15 1312 1313 extern int drbd_bm_init(struct drbd_conf *mdev); 1314 extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors); 1315 extern void drbd_bm_cleanup(struct drbd_conf *mdev); 1316 extern void drbd_bm_set_all(struct drbd_conf *mdev); 1317 extern void drbd_bm_clear_all(struct drbd_conf *mdev); 1318 extern int drbd_bm_set_bits( 1319 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1320 extern int drbd_bm_clear_bits( 1321 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1322 /* bm_set_bits variant for use while holding drbd_bm_lock */ 1323 extern void _drbd_bm_set_bits(struct drbd_conf *mdev, 1324 const unsigned long s, const unsigned long e); 1325 extern int drbd_bm_test_bit(struct drbd_conf *mdev, unsigned long bitnr); 1326 extern int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr); 1327 extern int drbd_bm_write_sect(struct drbd_conf *mdev, unsigned long enr) __must_hold(local); 1328 extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local); 1329 extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local); 1330 extern unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev, 1331 unsigned long al_enr); 1332 extern size_t drbd_bm_words(struct drbd_conf *mdev); 1333 extern unsigned long drbd_bm_bits(struct drbd_conf *mdev); 1334 extern sector_t drbd_bm_capacity(struct drbd_conf *mdev); 1335 extern unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1336 /* bm_find_next variants for use while you hold drbd_bm_lock() */ 1337 extern unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1338 extern unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo); 1339 extern unsigned long drbd_bm_total_weight(struct drbd_conf *mdev); 1340 extern int drbd_bm_rs_done(struct drbd_conf *mdev); 1341 /* for receive_bitmap */ 1342 extern void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset, 1343 size_t number, unsigned long *buffer); 1344 /* for _drbd_send_bitmap and drbd_bm_write_sect */ 1345 extern void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset, 1346 size_t number, unsigned long *buffer); 1347 1348 extern void drbd_bm_lock(struct drbd_conf *mdev, char *why); 1349 extern void drbd_bm_unlock(struct drbd_conf *mdev); 1350 1351 extern int drbd_bm_count_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e); 1352 /* drbd_main.c */ 1353 1354 extern struct kmem_cache *drbd_request_cache; 1355 extern struct kmem_cache *drbd_ee_cache; /* epoch entries */ 1356 extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 1357 extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 1358 extern mempool_t *drbd_request_mempool; 1359 extern mempool_t *drbd_ee_mempool; 1360 1361 extern struct page *drbd_pp_pool; /* drbd's page pool */ 1362 extern spinlock_t drbd_pp_lock; 1363 extern int drbd_pp_vacant; 1364 extern wait_queue_head_t drbd_pp_wait; 1365 1366 extern rwlock_t global_state_lock; 1367 1368 extern struct drbd_conf *drbd_new_device(unsigned int minor); 1369 extern void drbd_free_mdev(struct drbd_conf *mdev); 1370 1371 extern int proc_details; 1372 1373 /* drbd_req */ 1374 extern int drbd_make_request_26(struct request_queue *q, struct bio *bio); 1375 extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req); 1376 extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec); 1377 extern int is_valid_ar_handle(struct drbd_request *, sector_t); 1378 1379 1380 /* drbd_nl.c */ 1381 extern void drbd_suspend_io(struct drbd_conf *mdev); 1382 extern void drbd_resume_io(struct drbd_conf *mdev); 1383 extern char *ppsize(char *buf, unsigned long long size); 1384 extern sector_t drbd_new_dev_size(struct drbd_conf *, struct drbd_backing_dev *, int); 1385 enum determine_dev_size { dev_size_error = -1, unchanged = 0, shrunk = 1, grew = 2 }; 1386 extern enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *, int force) __must_hold(local); 1387 extern void resync_after_online_grow(struct drbd_conf *); 1388 extern void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int) __must_hold(local); 1389 extern int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, 1390 int force); 1391 enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev); 1392 extern int drbd_khelper(struct drbd_conf *mdev, char *cmd); 1393 1394 /* drbd_worker.c */ 1395 extern int drbd_worker(struct drbd_thread *thi); 1396 extern int drbd_alter_sa(struct drbd_conf *mdev, int na); 1397 extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side); 1398 extern void resume_next_sg(struct drbd_conf *mdev); 1399 extern void suspend_other_sg(struct drbd_conf *mdev); 1400 extern int drbd_resync_finished(struct drbd_conf *mdev); 1401 /* maybe rather drbd_main.c ? */ 1402 extern int drbd_md_sync_page_io(struct drbd_conf *mdev, 1403 struct drbd_backing_dev *bdev, sector_t sector, int rw); 1404 extern void drbd_ov_oos_found(struct drbd_conf*, sector_t, int); 1405 1406 static inline void ov_oos_print(struct drbd_conf *mdev) 1407 { 1408 if (mdev->ov_last_oos_size) { 1409 dev_err(DEV, "Out of sync: start=%llu, size=%lu (sectors)\n", 1410 (unsigned long long)mdev->ov_last_oos_start, 1411 (unsigned long)mdev->ov_last_oos_size); 1412 } 1413 mdev->ov_last_oos_size=0; 1414 } 1415 1416 1417 extern void drbd_csum(struct drbd_conf *, struct crypto_hash *, struct bio *, void *); 1418 /* worker callbacks */ 1419 extern int w_req_cancel_conflict(struct drbd_conf *, struct drbd_work *, int); 1420 extern int w_read_retry_remote(struct drbd_conf *, struct drbd_work *, int); 1421 extern int w_e_end_data_req(struct drbd_conf *, struct drbd_work *, int); 1422 extern int w_e_end_rsdata_req(struct drbd_conf *, struct drbd_work *, int); 1423 extern int w_e_end_csum_rs_req(struct drbd_conf *, struct drbd_work *, int); 1424 extern int w_e_end_ov_reply(struct drbd_conf *, struct drbd_work *, int); 1425 extern int w_e_end_ov_req(struct drbd_conf *, struct drbd_work *, int); 1426 extern int w_ov_finished(struct drbd_conf *, struct drbd_work *, int); 1427 extern int w_resync_inactive(struct drbd_conf *, struct drbd_work *, int); 1428 extern int w_resume_next_sg(struct drbd_conf *, struct drbd_work *, int); 1429 extern int w_io_error(struct drbd_conf *, struct drbd_work *, int); 1430 extern int w_send_write_hint(struct drbd_conf *, struct drbd_work *, int); 1431 extern int w_make_resync_request(struct drbd_conf *, struct drbd_work *, int); 1432 extern int w_send_dblock(struct drbd_conf *, struct drbd_work *, int); 1433 extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int); 1434 extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int); 1435 extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int); 1436 extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int); 1437 1438 extern void resync_timer_fn(unsigned long data); 1439 1440 /* drbd_receiver.c */ 1441 extern int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list); 1442 extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev, 1443 u64 id, 1444 sector_t sector, 1445 unsigned int data_size, 1446 gfp_t gfp_mask) __must_hold(local); 1447 extern void drbd_free_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e); 1448 extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1449 struct list_head *head); 1450 extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1451 struct list_head *head); 1452 extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled); 1453 extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed); 1454 extern void drbd_flush_workqueue(struct drbd_conf *mdev); 1455 1456 /* yes, there is kernel_setsockopt, but only since 2.6.18. we don't need to 1457 * mess with get_fs/set_fs, we know we are KERNEL_DS always. */ 1458 static inline int drbd_setsockopt(struct socket *sock, int level, int optname, 1459 char __user *optval, int optlen) 1460 { 1461 int err; 1462 if (level == SOL_SOCKET) 1463 err = sock_setsockopt(sock, level, optname, optval, optlen); 1464 else 1465 err = sock->ops->setsockopt(sock, level, optname, optval, 1466 optlen); 1467 return err; 1468 } 1469 1470 static inline void drbd_tcp_cork(struct socket *sock) 1471 { 1472 int __user val = 1; 1473 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1474 (char __user *)&val, sizeof(val)); 1475 } 1476 1477 static inline void drbd_tcp_uncork(struct socket *sock) 1478 { 1479 int __user val = 0; 1480 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1481 (char __user *)&val, sizeof(val)); 1482 } 1483 1484 static inline void drbd_tcp_nodelay(struct socket *sock) 1485 { 1486 int __user val = 1; 1487 (void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY, 1488 (char __user *)&val, sizeof(val)); 1489 } 1490 1491 static inline void drbd_tcp_quickack(struct socket *sock) 1492 { 1493 int __user val = 1; 1494 (void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK, 1495 (char __user *)&val, sizeof(val)); 1496 } 1497 1498 void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo); 1499 1500 /* drbd_proc.c */ 1501 extern struct proc_dir_entry *drbd_proc; 1502 extern const struct file_operations drbd_proc_fops; 1503 extern const char *drbd_conn_str(enum drbd_conns s); 1504 extern const char *drbd_role_str(enum drbd_role s); 1505 1506 /* drbd_actlog.c */ 1507 extern void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector); 1508 extern void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector); 1509 extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector); 1510 extern int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1511 extern int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1512 extern void drbd_rs_cancel_all(struct drbd_conf *mdev); 1513 extern int drbd_rs_del_all(struct drbd_conf *mdev); 1514 extern void drbd_rs_failed_io(struct drbd_conf *mdev, 1515 sector_t sector, int size); 1516 extern int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *); 1517 extern void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector, 1518 int size, const char *file, const unsigned int line); 1519 #define drbd_set_in_sync(mdev, sector, size) \ 1520 __drbd_set_in_sync(mdev, sector, size, __FILE__, __LINE__) 1521 extern void __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector, 1522 int size, const char *file, const unsigned int line); 1523 #define drbd_set_out_of_sync(mdev, sector, size) \ 1524 __drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__) 1525 extern void drbd_al_apply_to_bm(struct drbd_conf *mdev); 1526 extern void drbd_al_to_on_disk_bm(struct drbd_conf *mdev); 1527 extern void drbd_al_shrink(struct drbd_conf *mdev); 1528 1529 1530 /* drbd_nl.c */ 1531 1532 void drbd_nl_cleanup(void); 1533 int __init drbd_nl_init(void); 1534 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state); 1535 void drbd_bcast_sync_progress(struct drbd_conf *mdev); 1536 void drbd_bcast_ee(struct drbd_conf *mdev, 1537 const char *reason, const int dgs, 1538 const char* seen_hash, const char* calc_hash, 1539 const struct drbd_epoch_entry* e); 1540 1541 1542 /** 1543 * DOC: DRBD State macros 1544 * 1545 * These macros are used to express state changes in easily readable form. 1546 * 1547 * The NS macros expand to a mask and a value, that can be bit ored onto the 1548 * current state as soon as the spinlock (req_lock) was taken. 1549 * 1550 * The _NS macros are used for state functions that get called with the 1551 * spinlock. These macros expand directly to the new state value. 1552 * 1553 * Besides the basic forms NS() and _NS() additional _?NS[23] are defined 1554 * to express state changes that affect more than one aspect of the state. 1555 * 1556 * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY) 1557 * Means that the network connection was established and that the peer 1558 * is in secondary role. 1559 */ 1560 #define role_MASK R_MASK 1561 #define peer_MASK R_MASK 1562 #define disk_MASK D_MASK 1563 #define pdsk_MASK D_MASK 1564 #define conn_MASK C_MASK 1565 #define susp_MASK 1 1566 #define user_isp_MASK 1 1567 #define aftr_isp_MASK 1 1568 1569 #define NS(T, S) \ 1570 ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \ 1571 ({ union drbd_state val; val.i = 0; val.T = (S); val; }) 1572 #define NS2(T1, S1, T2, S2) \ 1573 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1574 mask.T2 = T2##_MASK; mask; }), \ 1575 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1576 val.T2 = (S2); val; }) 1577 #define NS3(T1, S1, T2, S2, T3, S3) \ 1578 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1579 mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \ 1580 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1581 val.T2 = (S2); val.T3 = (S3); val; }) 1582 1583 #define _NS(D, T, S) \ 1584 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; }) 1585 #define _NS2(D, T1, S1, T2, S2) \ 1586 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1587 __ns.T2 = (S2); __ns; }) 1588 #define _NS3(D, T1, S1, T2, S2, T3, S3) \ 1589 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1590 __ns.T2 = (S2); __ns.T3 = (S3); __ns; }) 1591 1592 /* 1593 * inline helper functions 1594 *************************/ 1595 1596 static inline void drbd_state_lock(struct drbd_conf *mdev) 1597 { 1598 wait_event(mdev->misc_wait, 1599 !test_and_set_bit(CLUSTER_ST_CHANGE, &mdev->flags)); 1600 } 1601 1602 static inline void drbd_state_unlock(struct drbd_conf *mdev) 1603 { 1604 clear_bit(CLUSTER_ST_CHANGE, &mdev->flags); 1605 wake_up(&mdev->misc_wait); 1606 } 1607 1608 static inline int _drbd_set_state(struct drbd_conf *mdev, 1609 union drbd_state ns, enum chg_state_flags flags, 1610 struct completion *done) 1611 { 1612 int rv; 1613 1614 read_lock(&global_state_lock); 1615 rv = __drbd_set_state(mdev, ns, flags, done); 1616 read_unlock(&global_state_lock); 1617 1618 return rv; 1619 } 1620 1621 /** 1622 * drbd_request_state() - Reqest a state change 1623 * @mdev: DRBD device. 1624 * @mask: mask of state bits to change. 1625 * @val: value of new state bits. 1626 * 1627 * This is the most graceful way of requesting a state change. It is verbose 1628 * quite verbose in case the state change is not possible, and all those 1629 * state changes are globally serialized. 1630 */ 1631 static inline int drbd_request_state(struct drbd_conf *mdev, 1632 union drbd_state mask, 1633 union drbd_state val) 1634 { 1635 return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED); 1636 } 1637 1638 #define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__) 1639 static inline void __drbd_chk_io_error_(struct drbd_conf *mdev, int forcedetach, const char *where) 1640 { 1641 switch (mdev->ldev->dc.on_io_error) { 1642 case EP_PASS_ON: 1643 if (!forcedetach) { 1644 if (printk_ratelimit()) 1645 dev_err(DEV, "Local IO failed in %s." 1646 "Passing error on...\n", where); 1647 break; 1648 } 1649 /* NOTE fall through to detach case if forcedetach set */ 1650 case EP_DETACH: 1651 case EP_CALL_HELPER: 1652 if (mdev->state.disk > D_FAILED) { 1653 _drbd_set_state(_NS(mdev, disk, D_FAILED), CS_HARD, NULL); 1654 dev_err(DEV, "Local IO failed in %s." 1655 "Detaching...\n", where); 1656 } 1657 break; 1658 } 1659 } 1660 1661 /** 1662 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers 1663 * @mdev: DRBD device. 1664 * @error: Error code passed to the IO completion callback 1665 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data 1666 * 1667 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED) 1668 */ 1669 #define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__) 1670 static inline void drbd_chk_io_error_(struct drbd_conf *mdev, 1671 int error, int forcedetach, const char *where) 1672 { 1673 if (error) { 1674 unsigned long flags; 1675 spin_lock_irqsave(&mdev->req_lock, flags); 1676 __drbd_chk_io_error_(mdev, forcedetach, where); 1677 spin_unlock_irqrestore(&mdev->req_lock, flags); 1678 } 1679 } 1680 1681 1682 /** 1683 * drbd_md_first_sector() - Returns the first sector number of the meta data area 1684 * @bdev: Meta data block device. 1685 * 1686 * BTW, for internal meta data, this happens to be the maximum capacity 1687 * we could agree upon with our peer node. 1688 */ 1689 static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev) 1690 { 1691 switch (bdev->dc.meta_dev_idx) { 1692 case DRBD_MD_INDEX_INTERNAL: 1693 case DRBD_MD_INDEX_FLEX_INT: 1694 return bdev->md.md_offset + bdev->md.bm_offset; 1695 case DRBD_MD_INDEX_FLEX_EXT: 1696 default: 1697 return bdev->md.md_offset; 1698 } 1699 } 1700 1701 /** 1702 * drbd_md_last_sector() - Return the last sector number of the meta data area 1703 * @bdev: Meta data block device. 1704 */ 1705 static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev) 1706 { 1707 switch (bdev->dc.meta_dev_idx) { 1708 case DRBD_MD_INDEX_INTERNAL: 1709 case DRBD_MD_INDEX_FLEX_INT: 1710 return bdev->md.md_offset + MD_AL_OFFSET - 1; 1711 case DRBD_MD_INDEX_FLEX_EXT: 1712 default: 1713 return bdev->md.md_offset + bdev->md.md_size_sect; 1714 } 1715 } 1716 1717 /* Returns the number of 512 byte sectors of the device */ 1718 static inline sector_t drbd_get_capacity(struct block_device *bdev) 1719 { 1720 /* return bdev ? get_capacity(bdev->bd_disk) : 0; */ 1721 return bdev ? bdev->bd_inode->i_size >> 9 : 0; 1722 } 1723 1724 /** 1725 * drbd_get_max_capacity() - Returns the capacity we announce to out peer 1726 * @bdev: Meta data block device. 1727 * 1728 * returns the capacity we announce to out peer. we clip ourselves at the 1729 * various MAX_SECTORS, because if we don't, current implementation will 1730 * oops sooner or later 1731 */ 1732 static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev) 1733 { 1734 sector_t s; 1735 switch (bdev->dc.meta_dev_idx) { 1736 case DRBD_MD_INDEX_INTERNAL: 1737 case DRBD_MD_INDEX_FLEX_INT: 1738 s = drbd_get_capacity(bdev->backing_bdev) 1739 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1740 drbd_md_first_sector(bdev)) 1741 : 0; 1742 break; 1743 case DRBD_MD_INDEX_FLEX_EXT: 1744 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1745 drbd_get_capacity(bdev->backing_bdev)); 1746 /* clip at maximum size the meta device can support */ 1747 s = min_t(sector_t, s, 1748 BM_EXT_TO_SECT(bdev->md.md_size_sect 1749 - bdev->md.bm_offset)); 1750 break; 1751 default: 1752 s = min_t(sector_t, DRBD_MAX_SECTORS, 1753 drbd_get_capacity(bdev->backing_bdev)); 1754 } 1755 return s; 1756 } 1757 1758 /** 1759 * drbd_md_ss__() - Return the sector number of our meta data super block 1760 * @mdev: DRBD device. 1761 * @bdev: Meta data block device. 1762 */ 1763 static inline sector_t drbd_md_ss__(struct drbd_conf *mdev, 1764 struct drbd_backing_dev *bdev) 1765 { 1766 switch (bdev->dc.meta_dev_idx) { 1767 default: /* external, some index */ 1768 return MD_RESERVED_SECT * bdev->dc.meta_dev_idx; 1769 case DRBD_MD_INDEX_INTERNAL: 1770 /* with drbd08, internal meta data is always "flexible" */ 1771 case DRBD_MD_INDEX_FLEX_INT: 1772 /* sizeof(struct md_on_disk_07) == 4k 1773 * position: last 4k aligned block of 4k size */ 1774 if (!bdev->backing_bdev) { 1775 if (__ratelimit(&drbd_ratelimit_state)) { 1776 dev_err(DEV, "bdev->backing_bdev==NULL\n"); 1777 dump_stack(); 1778 } 1779 return 0; 1780 } 1781 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL) 1782 - MD_AL_OFFSET; 1783 case DRBD_MD_INDEX_FLEX_EXT: 1784 return 0; 1785 } 1786 } 1787 1788 static inline void 1789 _drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 1790 { 1791 list_add_tail(&w->list, &q->q); 1792 up(&q->s); 1793 } 1794 1795 static inline void 1796 drbd_queue_work_front(struct drbd_work_queue *q, struct drbd_work *w) 1797 { 1798 unsigned long flags; 1799 spin_lock_irqsave(&q->q_lock, flags); 1800 list_add(&w->list, &q->q); 1801 up(&q->s); /* within the spinlock, 1802 see comment near end of drbd_worker() */ 1803 spin_unlock_irqrestore(&q->q_lock, flags); 1804 } 1805 1806 static inline void 1807 drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 1808 { 1809 unsigned long flags; 1810 spin_lock_irqsave(&q->q_lock, flags); 1811 list_add_tail(&w->list, &q->q); 1812 up(&q->s); /* within the spinlock, 1813 see comment near end of drbd_worker() */ 1814 spin_unlock_irqrestore(&q->q_lock, flags); 1815 } 1816 1817 static inline void wake_asender(struct drbd_conf *mdev) 1818 { 1819 if (test_bit(SIGNAL_ASENDER, &mdev->flags)) 1820 force_sig(DRBD_SIG, mdev->asender.task); 1821 } 1822 1823 static inline void request_ping(struct drbd_conf *mdev) 1824 { 1825 set_bit(SEND_PING, &mdev->flags); 1826 wake_asender(mdev); 1827 } 1828 1829 static inline int drbd_send_short_cmd(struct drbd_conf *mdev, 1830 enum drbd_packets cmd) 1831 { 1832 struct p_header h; 1833 return drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, &h, sizeof(h)); 1834 } 1835 1836 static inline int drbd_send_ping(struct drbd_conf *mdev) 1837 { 1838 struct p_header h; 1839 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING, &h, sizeof(h)); 1840 } 1841 1842 static inline int drbd_send_ping_ack(struct drbd_conf *mdev) 1843 { 1844 struct p_header h; 1845 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING_ACK, &h, sizeof(h)); 1846 } 1847 1848 static inline void drbd_thread_stop(struct drbd_thread *thi) 1849 { 1850 _drbd_thread_stop(thi, FALSE, TRUE); 1851 } 1852 1853 static inline void drbd_thread_stop_nowait(struct drbd_thread *thi) 1854 { 1855 _drbd_thread_stop(thi, FALSE, FALSE); 1856 } 1857 1858 static inline void drbd_thread_restart_nowait(struct drbd_thread *thi) 1859 { 1860 _drbd_thread_stop(thi, TRUE, FALSE); 1861 } 1862 1863 /* counts how many answer packets packets we expect from our peer, 1864 * for either explicit application requests, 1865 * or implicit barrier packets as necessary. 1866 * increased: 1867 * w_send_barrier 1868 * _req_mod(req, queue_for_net_write or queue_for_net_read); 1869 * it is much easier and equally valid to count what we queue for the 1870 * worker, even before it actually was queued or send. 1871 * (drbd_make_request_common; recovery path on read io-error) 1872 * decreased: 1873 * got_BarrierAck (respective tl_clear, tl_clear_barrier) 1874 * _req_mod(req, data_received) 1875 * [from receive_DataReply] 1876 * _req_mod(req, write_acked_by_peer or recv_acked_by_peer or neg_acked) 1877 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)] 1878 * for some reason it is NOT decreased in got_NegAck, 1879 * but in the resulting cleanup code from report_params. 1880 * we should try to remember the reason for that... 1881 * _req_mod(req, send_failed or send_canceled) 1882 * _req_mod(req, connection_lost_while_pending) 1883 * [from tl_clear_barrier] 1884 */ 1885 static inline void inc_ap_pending(struct drbd_conf *mdev) 1886 { 1887 atomic_inc(&mdev->ap_pending_cnt); 1888 } 1889 1890 #define ERR_IF_CNT_IS_NEGATIVE(which) \ 1891 if (atomic_read(&mdev->which) < 0) \ 1892 dev_err(DEV, "in %s:%d: " #which " = %d < 0 !\n", \ 1893 __func__ , __LINE__ , \ 1894 atomic_read(&mdev->which)) 1895 1896 #define dec_ap_pending(mdev) do { \ 1897 typecheck(struct drbd_conf *, mdev); \ 1898 if (atomic_dec_and_test(&mdev->ap_pending_cnt)) \ 1899 wake_up(&mdev->misc_wait); \ 1900 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt); } while (0) 1901 1902 /* counts how many resync-related answers we still expect from the peer 1903 * increase decrease 1904 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY) 1905 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK whith ID_SYNCER) 1906 * (or P_NEG_ACK with ID_SYNCER) 1907 */ 1908 static inline void inc_rs_pending(struct drbd_conf *mdev) 1909 { 1910 atomic_inc(&mdev->rs_pending_cnt); 1911 } 1912 1913 #define dec_rs_pending(mdev) do { \ 1914 typecheck(struct drbd_conf *, mdev); \ 1915 atomic_dec(&mdev->rs_pending_cnt); \ 1916 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt); } while (0) 1917 1918 /* counts how many answers we still need to send to the peer. 1919 * increased on 1920 * receive_Data unless protocol A; 1921 * we need to send a P_RECV_ACK (proto B) 1922 * or P_WRITE_ACK (proto C) 1923 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK 1924 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA 1925 * receive_Barrier_* we need to send a P_BARRIER_ACK 1926 */ 1927 static inline void inc_unacked(struct drbd_conf *mdev) 1928 { 1929 atomic_inc(&mdev->unacked_cnt); 1930 } 1931 1932 #define dec_unacked(mdev) do { \ 1933 typecheck(struct drbd_conf *, mdev); \ 1934 atomic_dec(&mdev->unacked_cnt); \ 1935 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 1936 1937 #define sub_unacked(mdev, n) do { \ 1938 typecheck(struct drbd_conf *, mdev); \ 1939 atomic_sub(n, &mdev->unacked_cnt); \ 1940 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 1941 1942 1943 static inline void put_net_conf(struct drbd_conf *mdev) 1944 { 1945 if (atomic_dec_and_test(&mdev->net_cnt)) 1946 wake_up(&mdev->misc_wait); 1947 } 1948 1949 /** 1950 * get_net_conf() - Increase ref count on mdev->net_conf; Returns 0 if nothing there 1951 * @mdev: DRBD device. 1952 * 1953 * You have to call put_net_conf() when finished working with mdev->net_conf. 1954 */ 1955 static inline int get_net_conf(struct drbd_conf *mdev) 1956 { 1957 int have_net_conf; 1958 1959 atomic_inc(&mdev->net_cnt); 1960 have_net_conf = mdev->state.conn >= C_UNCONNECTED; 1961 if (!have_net_conf) 1962 put_net_conf(mdev); 1963 return have_net_conf; 1964 } 1965 1966 /** 1967 * get_ldev() - Increase the ref count on mdev->ldev. Returns 0 if there is no ldev 1968 * @M: DRBD device. 1969 * 1970 * You have to call put_ldev() when finished working with mdev->ldev. 1971 */ 1972 #define get_ldev(M) __cond_lock(local, _get_ldev_if_state(M,D_INCONSISTENT)) 1973 #define get_ldev_if_state(M,MINS) __cond_lock(local, _get_ldev_if_state(M,MINS)) 1974 1975 static inline void put_ldev(struct drbd_conf *mdev) 1976 { 1977 __release(local); 1978 if (atomic_dec_and_test(&mdev->local_cnt)) 1979 wake_up(&mdev->misc_wait); 1980 D_ASSERT(atomic_read(&mdev->local_cnt) >= 0); 1981 } 1982 1983 #ifndef __CHECKER__ 1984 static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins) 1985 { 1986 int io_allowed; 1987 1988 atomic_inc(&mdev->local_cnt); 1989 io_allowed = (mdev->state.disk >= mins); 1990 if (!io_allowed) 1991 put_ldev(mdev); 1992 return io_allowed; 1993 } 1994 #else 1995 extern int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins); 1996 #endif 1997 1998 /* you must have an "get_ldev" reference */ 1999 static inline void drbd_get_syncer_progress(struct drbd_conf *mdev, 2000 unsigned long *bits_left, unsigned int *per_mil_done) 2001 { 2002 /* 2003 * this is to break it at compile time when we change that 2004 * (we may feel 4TB maximum storage per drbd is not enough) 2005 */ 2006 typecheck(unsigned long, mdev->rs_total); 2007 2008 /* note: both rs_total and rs_left are in bits, i.e. in 2009 * units of BM_BLOCK_SIZE. 2010 * for the percentage, we don't care. */ 2011 2012 *bits_left = drbd_bm_total_weight(mdev) - mdev->rs_failed; 2013 /* >> 10 to prevent overflow, 2014 * +1 to prevent division by zero */ 2015 if (*bits_left > mdev->rs_total) { 2016 /* doh. maybe a logic bug somewhere. 2017 * may also be just a race condition 2018 * between this and a disconnect during sync. 2019 * for now, just prevent in-kernel buffer overflow. 2020 */ 2021 smp_rmb(); 2022 dev_warn(DEV, "cs:%s rs_left=%lu > rs_total=%lu (rs_failed %lu)\n", 2023 drbd_conn_str(mdev->state.conn), 2024 *bits_left, mdev->rs_total, mdev->rs_failed); 2025 *per_mil_done = 0; 2026 } else { 2027 /* make sure the calculation happens in long context */ 2028 unsigned long tmp = 1000UL - 2029 (*bits_left >> 10)*1000UL 2030 / ((mdev->rs_total >> 10) + 1UL); 2031 *per_mil_done = tmp; 2032 } 2033 } 2034 2035 2036 /* this throttles on-the-fly application requests 2037 * according to max_buffers settings; 2038 * maybe re-implement using semaphores? */ 2039 static inline int drbd_get_max_buffers(struct drbd_conf *mdev) 2040 { 2041 int mxb = 1000000; /* arbitrary limit on open requests */ 2042 if (get_net_conf(mdev)) { 2043 mxb = mdev->net_conf->max_buffers; 2044 put_net_conf(mdev); 2045 } 2046 return mxb; 2047 } 2048 2049 static inline int drbd_state_is_stable(union drbd_state s) 2050 { 2051 2052 /* DO NOT add a default clause, we want the compiler to warn us 2053 * for any newly introduced state we may have forgotten to add here */ 2054 2055 switch ((enum drbd_conns)s.conn) { 2056 /* new io only accepted when there is no connection, ... */ 2057 case C_STANDALONE: 2058 case C_WF_CONNECTION: 2059 /* ... or there is a well established connection. */ 2060 case C_CONNECTED: 2061 case C_SYNC_SOURCE: 2062 case C_SYNC_TARGET: 2063 case C_VERIFY_S: 2064 case C_VERIFY_T: 2065 case C_PAUSED_SYNC_S: 2066 case C_PAUSED_SYNC_T: 2067 /* maybe stable, look at the disk state */ 2068 break; 2069 2070 /* no new io accepted during tansitional states 2071 * like handshake or teardown */ 2072 case C_DISCONNECTING: 2073 case C_UNCONNECTED: 2074 case C_TIMEOUT: 2075 case C_BROKEN_PIPE: 2076 case C_NETWORK_FAILURE: 2077 case C_PROTOCOL_ERROR: 2078 case C_TEAR_DOWN: 2079 case C_WF_REPORT_PARAMS: 2080 case C_STARTING_SYNC_S: 2081 case C_STARTING_SYNC_T: 2082 case C_WF_BITMAP_S: 2083 case C_WF_BITMAP_T: 2084 case C_WF_SYNC_UUID: 2085 case C_MASK: 2086 /* not "stable" */ 2087 return 0; 2088 } 2089 2090 switch ((enum drbd_disk_state)s.disk) { 2091 case D_DISKLESS: 2092 case D_INCONSISTENT: 2093 case D_OUTDATED: 2094 case D_CONSISTENT: 2095 case D_UP_TO_DATE: 2096 /* disk state is stable as well. */ 2097 break; 2098 2099 /* no new io accepted during tansitional states */ 2100 case D_ATTACHING: 2101 case D_FAILED: 2102 case D_NEGOTIATING: 2103 case D_UNKNOWN: 2104 case D_MASK: 2105 /* not "stable" */ 2106 return 0; 2107 } 2108 2109 return 1; 2110 } 2111 2112 static inline int __inc_ap_bio_cond(struct drbd_conf *mdev) 2113 { 2114 int mxb = drbd_get_max_buffers(mdev); 2115 2116 if (mdev->state.susp) 2117 return 0; 2118 if (test_bit(SUSPEND_IO, &mdev->flags)) 2119 return 0; 2120 2121 /* to avoid potential deadlock or bitmap corruption, 2122 * in various places, we only allow new application io 2123 * to start during "stable" states. */ 2124 2125 /* no new io accepted when attaching or detaching the disk */ 2126 if (!drbd_state_is_stable(mdev->state)) 2127 return 0; 2128 2129 /* since some older kernels don't have atomic_add_unless, 2130 * and we are within the spinlock anyways, we have this workaround. */ 2131 if (atomic_read(&mdev->ap_bio_cnt) > mxb) 2132 return 0; 2133 if (test_bit(BITMAP_IO, &mdev->flags)) 2134 return 0; 2135 return 1; 2136 } 2137 2138 /* I'd like to use wait_event_lock_irq, 2139 * but I'm not sure when it got introduced, 2140 * and not sure when it has 3 or 4 arguments */ 2141 static inline void inc_ap_bio(struct drbd_conf *mdev, int one_or_two) 2142 { 2143 /* compare with after_state_ch, 2144 * os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S */ 2145 DEFINE_WAIT(wait); 2146 2147 /* we wait here 2148 * as long as the device is suspended 2149 * until the bitmap is no longer on the fly during connection 2150 * handshake as long as we would exeed the max_buffer limit. 2151 * 2152 * to avoid races with the reconnect code, 2153 * we need to atomic_inc within the spinlock. */ 2154 2155 spin_lock_irq(&mdev->req_lock); 2156 while (!__inc_ap_bio_cond(mdev)) { 2157 prepare_to_wait(&mdev->misc_wait, &wait, TASK_UNINTERRUPTIBLE); 2158 spin_unlock_irq(&mdev->req_lock); 2159 schedule(); 2160 finish_wait(&mdev->misc_wait, &wait); 2161 spin_lock_irq(&mdev->req_lock); 2162 } 2163 atomic_add(one_or_two, &mdev->ap_bio_cnt); 2164 spin_unlock_irq(&mdev->req_lock); 2165 } 2166 2167 static inline void dec_ap_bio(struct drbd_conf *mdev) 2168 { 2169 int mxb = drbd_get_max_buffers(mdev); 2170 int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt); 2171 2172 D_ASSERT(ap_bio >= 0); 2173 /* this currently does wake_up for every dec_ap_bio! 2174 * maybe rather introduce some type of hysteresis? 2175 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */ 2176 if (ap_bio < mxb) 2177 wake_up(&mdev->misc_wait); 2178 if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) { 2179 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags)) 2180 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w); 2181 } 2182 } 2183 2184 static inline void drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val) 2185 { 2186 mdev->ed_uuid = val; 2187 } 2188 2189 static inline int seq_cmp(u32 a, u32 b) 2190 { 2191 /* we assume wrap around at 32bit. 2192 * for wrap around at 24bit (old atomic_t), 2193 * we'd have to 2194 * a <<= 8; b <<= 8; 2195 */ 2196 return (s32)(a) - (s32)(b); 2197 } 2198 #define seq_lt(a, b) (seq_cmp((a), (b)) < 0) 2199 #define seq_gt(a, b) (seq_cmp((a), (b)) > 0) 2200 #define seq_ge(a, b) (seq_cmp((a), (b)) >= 0) 2201 #define seq_le(a, b) (seq_cmp((a), (b)) <= 0) 2202 /* CAUTION: please no side effects in arguments! */ 2203 #define seq_max(a, b) ((u32)(seq_gt((a), (b)) ? (a) : (b))) 2204 2205 static inline void update_peer_seq(struct drbd_conf *mdev, unsigned int new_seq) 2206 { 2207 unsigned int m; 2208 spin_lock(&mdev->peer_seq_lock); 2209 m = seq_max(mdev->peer_seq, new_seq); 2210 mdev->peer_seq = m; 2211 spin_unlock(&mdev->peer_seq_lock); 2212 if (m == new_seq) 2213 wake_up(&mdev->seq_wait); 2214 } 2215 2216 static inline void drbd_update_congested(struct drbd_conf *mdev) 2217 { 2218 struct sock *sk = mdev->data.socket->sk; 2219 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5) 2220 set_bit(NET_CONGESTED, &mdev->flags); 2221 } 2222 2223 static inline int drbd_queue_order_type(struct drbd_conf *mdev) 2224 { 2225 /* sorry, we currently have no working implementation 2226 * of distributed TCQ stuff */ 2227 #ifndef QUEUE_ORDERED_NONE 2228 #define QUEUE_ORDERED_NONE 0 2229 #endif 2230 return QUEUE_ORDERED_NONE; 2231 } 2232 2233 static inline void drbd_blk_run_queue(struct request_queue *q) 2234 { 2235 if (q && q->unplug_fn) 2236 q->unplug_fn(q); 2237 } 2238 2239 static inline void drbd_kick_lo(struct drbd_conf *mdev) 2240 { 2241 if (get_ldev(mdev)) { 2242 drbd_blk_run_queue(bdev_get_queue(mdev->ldev->backing_bdev)); 2243 put_ldev(mdev); 2244 } 2245 } 2246 2247 static inline void drbd_md_flush(struct drbd_conf *mdev) 2248 { 2249 int r; 2250 2251 if (test_bit(MD_NO_BARRIER, &mdev->flags)) 2252 return; 2253 2254 r = blkdev_issue_flush(mdev->ldev->md_bdev, NULL); 2255 if (r) { 2256 set_bit(MD_NO_BARRIER, &mdev->flags); 2257 dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r); 2258 } 2259 } 2260 2261 #endif 2262