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 DRBD_FAULT_RECEIVE = 9, /* Changes some bytes upon receiving a [rs]data block */ 136 137 DRBD_FAULT_MAX, 138 }; 139 140 #ifdef CONFIG_DRBD_FAULT_INJECTION 141 extern unsigned int 142 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type); 143 static inline int 144 drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) { 145 return fault_rate && 146 (enable_faults & (1<<type)) && 147 _drbd_insert_fault(mdev, type); 148 } 149 #define FAULT_ACTIVE(_m, _t) (drbd_insert_fault((_m), (_t))) 150 151 #else 152 #define FAULT_ACTIVE(_m, _t) (0) 153 #endif 154 155 /* integer division, round _UP_ to the next integer */ 156 #define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0)) 157 /* usual integer division */ 158 #define div_floor(A, B) ((A)/(B)) 159 160 /* drbd_meta-data.c (still in drbd_main.c) */ 161 /* 4th incarnation of the disk layout. */ 162 #define DRBD_MD_MAGIC (DRBD_MAGIC+4) 163 164 extern struct drbd_conf **minor_table; 165 extern struct ratelimit_state drbd_ratelimit_state; 166 167 /* on the wire */ 168 enum drbd_packets { 169 /* receiver (data socket) */ 170 P_DATA = 0x00, 171 P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */ 172 P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */ 173 P_BARRIER = 0x03, 174 P_BITMAP = 0x04, 175 P_BECOME_SYNC_TARGET = 0x05, 176 P_BECOME_SYNC_SOURCE = 0x06, 177 P_UNPLUG_REMOTE = 0x07, /* Used at various times to hint the peer */ 178 P_DATA_REQUEST = 0x08, /* Used to ask for a data block */ 179 P_RS_DATA_REQUEST = 0x09, /* Used to ask for a data block for resync */ 180 P_SYNC_PARAM = 0x0a, 181 P_PROTOCOL = 0x0b, 182 P_UUIDS = 0x0c, 183 P_SIZES = 0x0d, 184 P_STATE = 0x0e, 185 P_SYNC_UUID = 0x0f, 186 P_AUTH_CHALLENGE = 0x10, 187 P_AUTH_RESPONSE = 0x11, 188 P_STATE_CHG_REQ = 0x12, 189 190 /* asender (meta socket */ 191 P_PING = 0x13, 192 P_PING_ACK = 0x14, 193 P_RECV_ACK = 0x15, /* Used in protocol B */ 194 P_WRITE_ACK = 0x16, /* Used in protocol C */ 195 P_RS_WRITE_ACK = 0x17, /* Is a P_WRITE_ACK, additionally call set_in_sync(). */ 196 P_DISCARD_ACK = 0x18, /* Used in proto C, two-primaries conflict detection */ 197 P_NEG_ACK = 0x19, /* Sent if local disk is unusable */ 198 P_NEG_DREPLY = 0x1a, /* Local disk is broken... */ 199 P_NEG_RS_DREPLY = 0x1b, /* Local disk is broken... */ 200 P_BARRIER_ACK = 0x1c, 201 P_STATE_CHG_REPLY = 0x1d, 202 203 /* "new" commands, no longer fitting into the ordering scheme above */ 204 205 P_OV_REQUEST = 0x1e, /* data socket */ 206 P_OV_REPLY = 0x1f, 207 P_OV_RESULT = 0x20, /* meta socket */ 208 P_CSUM_RS_REQUEST = 0x21, /* data socket */ 209 P_RS_IS_IN_SYNC = 0x22, /* meta socket */ 210 P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */ 211 P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */ 212 /* P_CKPT_FENCE_REQ = 0x25, * currently reserved for protocol D */ 213 /* P_CKPT_DISABLE_REQ = 0x26, * currently reserved for protocol D */ 214 P_DELAY_PROBE = 0x27, /* is used on BOTH sockets */ 215 216 P_MAX_CMD = 0x28, 217 P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */ 218 P_MAX_OPT_CMD = 0x101, 219 220 /* special command ids for handshake */ 221 222 P_HAND_SHAKE_M = 0xfff1, /* First Packet on the MetaSock */ 223 P_HAND_SHAKE_S = 0xfff2, /* First Packet on the Socket */ 224 225 P_HAND_SHAKE = 0xfffe /* FIXED for the next century! */ 226 }; 227 228 static inline const char *cmdname(enum drbd_packets cmd) 229 { 230 /* THINK may need to become several global tables 231 * when we want to support more than 232 * one PRO_VERSION */ 233 static const char *cmdnames[] = { 234 [P_DATA] = "Data", 235 [P_DATA_REPLY] = "DataReply", 236 [P_RS_DATA_REPLY] = "RSDataReply", 237 [P_BARRIER] = "Barrier", 238 [P_BITMAP] = "ReportBitMap", 239 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget", 240 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource", 241 [P_UNPLUG_REMOTE] = "UnplugRemote", 242 [P_DATA_REQUEST] = "DataRequest", 243 [P_RS_DATA_REQUEST] = "RSDataRequest", 244 [P_SYNC_PARAM] = "SyncParam", 245 [P_SYNC_PARAM89] = "SyncParam89", 246 [P_PROTOCOL] = "ReportProtocol", 247 [P_UUIDS] = "ReportUUIDs", 248 [P_SIZES] = "ReportSizes", 249 [P_STATE] = "ReportState", 250 [P_SYNC_UUID] = "ReportSyncUUID", 251 [P_AUTH_CHALLENGE] = "AuthChallenge", 252 [P_AUTH_RESPONSE] = "AuthResponse", 253 [P_PING] = "Ping", 254 [P_PING_ACK] = "PingAck", 255 [P_RECV_ACK] = "RecvAck", 256 [P_WRITE_ACK] = "WriteAck", 257 [P_RS_WRITE_ACK] = "RSWriteAck", 258 [P_DISCARD_ACK] = "DiscardAck", 259 [P_NEG_ACK] = "NegAck", 260 [P_NEG_DREPLY] = "NegDReply", 261 [P_NEG_RS_DREPLY] = "NegRSDReply", 262 [P_BARRIER_ACK] = "BarrierAck", 263 [P_STATE_CHG_REQ] = "StateChgRequest", 264 [P_STATE_CHG_REPLY] = "StateChgReply", 265 [P_OV_REQUEST] = "OVRequest", 266 [P_OV_REPLY] = "OVReply", 267 [P_OV_RESULT] = "OVResult", 268 [P_CSUM_RS_REQUEST] = "CsumRSRequest", 269 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync", 270 [P_COMPRESSED_BITMAP] = "CBitmap", 271 [P_DELAY_PROBE] = "DelayProbe", 272 [P_MAX_CMD] = NULL, 273 }; 274 275 if (cmd == P_HAND_SHAKE_M) 276 return "HandShakeM"; 277 if (cmd == P_HAND_SHAKE_S) 278 return "HandShakeS"; 279 if (cmd == P_HAND_SHAKE) 280 return "HandShake"; 281 if (cmd >= P_MAX_CMD) 282 return "Unknown"; 283 return cmdnames[cmd]; 284 } 285 286 /* for sending/receiving the bitmap, 287 * possibly in some encoding scheme */ 288 struct bm_xfer_ctx { 289 /* "const" 290 * stores total bits and long words 291 * of the bitmap, so we don't need to 292 * call the accessor functions over and again. */ 293 unsigned long bm_bits; 294 unsigned long bm_words; 295 /* during xfer, current position within the bitmap */ 296 unsigned long bit_offset; 297 unsigned long word_offset; 298 299 /* statistics; index: (h->command == P_BITMAP) */ 300 unsigned packets[2]; 301 unsigned bytes[2]; 302 }; 303 304 extern void INFO_bm_xfer_stats(struct drbd_conf *mdev, 305 const char *direction, struct bm_xfer_ctx *c); 306 307 static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c) 308 { 309 /* word_offset counts "native long words" (32 or 64 bit), 310 * aligned at 64 bit. 311 * Encoded packet may end at an unaligned bit offset. 312 * In case a fallback clear text packet is transmitted in 313 * between, we adjust this offset back to the last 64bit 314 * aligned "native long word", which makes coding and decoding 315 * the plain text bitmap much more convenient. */ 316 #if BITS_PER_LONG == 64 317 c->word_offset = c->bit_offset >> 6; 318 #elif BITS_PER_LONG == 32 319 c->word_offset = c->bit_offset >> 5; 320 c->word_offset &= ~(1UL); 321 #else 322 # error "unsupported BITS_PER_LONG" 323 #endif 324 } 325 326 #ifndef __packed 327 #define __packed __attribute__((packed)) 328 #endif 329 330 /* This is the layout for a packet on the wire. 331 * The byteorder is the network byte order. 332 * (except block_id and barrier fields. 333 * these are pointers to local structs 334 * and have no relevance for the partner, 335 * which just echoes them as received.) 336 * 337 * NOTE that the payload starts at a long aligned offset, 338 * regardless of 32 or 64 bit arch! 339 */ 340 struct p_header { 341 u32 magic; 342 u16 command; 343 u16 length; /* bytes of data after this header */ 344 u8 payload[0]; 345 } __packed; 346 /* 8 bytes. packet FIXED for the next century! */ 347 348 /* 349 * short commands, packets without payload, plain p_header: 350 * P_PING 351 * P_PING_ACK 352 * P_BECOME_SYNC_TARGET 353 * P_BECOME_SYNC_SOURCE 354 * P_UNPLUG_REMOTE 355 */ 356 357 /* 358 * commands with out-of-struct payload: 359 * P_BITMAP (no additional fields) 360 * P_DATA, P_DATA_REPLY (see p_data) 361 * P_COMPRESSED_BITMAP (see receive_compressed_bitmap) 362 */ 363 364 /* these defines must not be changed without changing the protocol version */ 365 #define DP_HARDBARRIER 1 366 #define DP_RW_SYNC 2 367 #define DP_MAY_SET_IN_SYNC 4 368 369 struct p_data { 370 struct p_header head; 371 u64 sector; /* 64 bits sector number */ 372 u64 block_id; /* to identify the request in protocol B&C */ 373 u32 seq_num; 374 u32 dp_flags; 375 } __packed; 376 377 /* 378 * commands which share a struct: 379 * p_block_ack: 380 * P_RECV_ACK (proto B), P_WRITE_ACK (proto C), 381 * P_DISCARD_ACK (proto C, two-primaries conflict detection) 382 * p_block_req: 383 * P_DATA_REQUEST, P_RS_DATA_REQUEST 384 */ 385 struct p_block_ack { 386 struct p_header head; 387 u64 sector; 388 u64 block_id; 389 u32 blksize; 390 u32 seq_num; 391 } __packed; 392 393 394 struct p_block_req { 395 struct p_header head; 396 u64 sector; 397 u64 block_id; 398 u32 blksize; 399 u32 pad; /* to multiple of 8 Byte */ 400 } __packed; 401 402 /* 403 * commands with their own struct for additional fields: 404 * P_HAND_SHAKE 405 * P_BARRIER 406 * P_BARRIER_ACK 407 * P_SYNC_PARAM 408 * ReportParams 409 */ 410 411 struct p_handshake { 412 struct p_header head; /* 8 bytes */ 413 u32 protocol_min; 414 u32 feature_flags; 415 u32 protocol_max; 416 417 /* should be more than enough for future enhancements 418 * for now, feature_flags and the reserverd array shall be zero. 419 */ 420 421 u32 _pad; 422 u64 reserverd[7]; 423 } __packed; 424 /* 80 bytes, FIXED for the next century */ 425 426 struct p_barrier { 427 struct p_header head; 428 u32 barrier; /* barrier number _handle_ only */ 429 u32 pad; /* to multiple of 8 Byte */ 430 } __packed; 431 432 struct p_barrier_ack { 433 struct p_header head; 434 u32 barrier; 435 u32 set_size; 436 } __packed; 437 438 struct p_rs_param { 439 struct p_header head; 440 u32 rate; 441 442 /* Since protocol version 88 and higher. */ 443 char verify_alg[0]; 444 } __packed; 445 446 struct p_rs_param_89 { 447 struct p_header head; 448 u32 rate; 449 /* protocol version 89: */ 450 char verify_alg[SHARED_SECRET_MAX]; 451 char csums_alg[SHARED_SECRET_MAX]; 452 } __packed; 453 454 enum drbd_conn_flags { 455 CF_WANT_LOSE = 1, 456 CF_DRY_RUN = 2, 457 }; 458 459 struct p_protocol { 460 struct p_header head; 461 u32 protocol; 462 u32 after_sb_0p; 463 u32 after_sb_1p; 464 u32 after_sb_2p; 465 u32 conn_flags; 466 u32 two_primaries; 467 468 /* Since protocol version 87 and higher. */ 469 char integrity_alg[0]; 470 471 } __packed; 472 473 struct p_uuids { 474 struct p_header head; 475 u64 uuid[UI_EXTENDED_SIZE]; 476 } __packed; 477 478 struct p_rs_uuid { 479 struct p_header head; 480 u64 uuid; 481 } __packed; 482 483 struct p_sizes { 484 struct p_header head; 485 u64 d_size; /* size of disk */ 486 u64 u_size; /* user requested size */ 487 u64 c_size; /* current exported size */ 488 u32 max_segment_size; /* Maximal size of a BIO */ 489 u16 queue_order_type; /* not yet implemented in DRBD*/ 490 u16 dds_flags; /* use enum dds_flags here. */ 491 } __packed; 492 493 struct p_state { 494 struct p_header head; 495 u32 state; 496 } __packed; 497 498 struct p_req_state { 499 struct p_header head; 500 u32 mask; 501 u32 val; 502 } __packed; 503 504 struct p_req_state_reply { 505 struct p_header head; 506 u32 retcode; 507 } __packed; 508 509 struct p_drbd06_param { 510 u64 size; 511 u32 state; 512 u32 blksize; 513 u32 protocol; 514 u32 version; 515 u32 gen_cnt[5]; 516 u32 bit_map_gen[5]; 517 } __packed; 518 519 struct p_discard { 520 struct p_header head; 521 u64 block_id; 522 u32 seq_num; 523 u32 pad; 524 } __packed; 525 526 /* Valid values for the encoding field. 527 * Bump proto version when changing this. */ 528 enum drbd_bitmap_code { 529 /* RLE_VLI_Bytes = 0, 530 * and other bit variants had been defined during 531 * algorithm evaluation. */ 532 RLE_VLI_Bits = 2, 533 }; 534 535 struct p_compressed_bm { 536 struct p_header head; 537 /* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code 538 * (encoding & 0x80): polarity (set/unset) of first runlength 539 * ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits 540 * used to pad up to head.length bytes 541 */ 542 u8 encoding; 543 544 u8 code[0]; 545 } __packed; 546 547 struct p_delay_probe { 548 struct p_header head; 549 u32 seq_num; /* sequence number to match the two probe packets */ 550 u32 offset; /* usecs the probe got sent after the reference time point */ 551 } __packed; 552 553 struct delay_probe { 554 struct list_head list; 555 unsigned int seq_num; 556 struct timeval time; 557 }; 558 559 /* DCBP: Drbd Compressed Bitmap Packet ... */ 560 static inline enum drbd_bitmap_code 561 DCBP_get_code(struct p_compressed_bm *p) 562 { 563 return (enum drbd_bitmap_code)(p->encoding & 0x0f); 564 } 565 566 static inline void 567 DCBP_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code) 568 { 569 BUG_ON(code & ~0xf); 570 p->encoding = (p->encoding & ~0xf) | code; 571 } 572 573 static inline int 574 DCBP_get_start(struct p_compressed_bm *p) 575 { 576 return (p->encoding & 0x80) != 0; 577 } 578 579 static inline void 580 DCBP_set_start(struct p_compressed_bm *p, int set) 581 { 582 p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0); 583 } 584 585 static inline int 586 DCBP_get_pad_bits(struct p_compressed_bm *p) 587 { 588 return (p->encoding >> 4) & 0x7; 589 } 590 591 static inline void 592 DCBP_set_pad_bits(struct p_compressed_bm *p, int n) 593 { 594 BUG_ON(n & ~0x7); 595 p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4); 596 } 597 598 /* one bitmap packet, including the p_header, 599 * should fit within one _architecture independend_ page. 600 * so we need to use the fixed size 4KiB page size 601 * most architechtures have used for a long time. 602 */ 603 #define BM_PACKET_PAYLOAD_BYTES (4096 - sizeof(struct p_header)) 604 #define BM_PACKET_WORDS (BM_PACKET_PAYLOAD_BYTES/sizeof(long)) 605 #define BM_PACKET_VLI_BYTES_MAX (4096 - sizeof(struct p_compressed_bm)) 606 #if (PAGE_SIZE < 4096) 607 /* drbd_send_bitmap / receive_bitmap would break horribly */ 608 #error "PAGE_SIZE too small" 609 #endif 610 611 union p_polymorph { 612 struct p_header header; 613 struct p_handshake handshake; 614 struct p_data data; 615 struct p_block_ack block_ack; 616 struct p_barrier barrier; 617 struct p_barrier_ack barrier_ack; 618 struct p_rs_param_89 rs_param_89; 619 struct p_protocol protocol; 620 struct p_sizes sizes; 621 struct p_uuids uuids; 622 struct p_state state; 623 struct p_req_state req_state; 624 struct p_req_state_reply req_state_reply; 625 struct p_block_req block_req; 626 } __packed; 627 628 /**********************************************************************/ 629 enum drbd_thread_state { 630 None, 631 Running, 632 Exiting, 633 Restarting 634 }; 635 636 struct drbd_thread { 637 spinlock_t t_lock; 638 struct task_struct *task; 639 struct completion stop; 640 enum drbd_thread_state t_state; 641 int (*function) (struct drbd_thread *); 642 struct drbd_conf *mdev; 643 int reset_cpu_mask; 644 }; 645 646 static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi) 647 { 648 /* THINK testing the t_state seems to be uncritical in all cases 649 * (but thread_{start,stop}), so we can read it *without* the lock. 650 * --lge */ 651 652 smp_rmb(); 653 return thi->t_state; 654 } 655 656 657 /* 658 * Having this as the first member of a struct provides sort of "inheritance". 659 * "derived" structs can be "drbd_queue_work()"ed. 660 * The callback should know and cast back to the descendant struct. 661 * drbd_request and drbd_epoch_entry are descendants of drbd_work. 662 */ 663 struct drbd_work; 664 typedef int (*drbd_work_cb)(struct drbd_conf *, struct drbd_work *, int cancel); 665 struct drbd_work { 666 struct list_head list; 667 drbd_work_cb cb; 668 }; 669 670 struct drbd_tl_epoch; 671 struct drbd_request { 672 struct drbd_work w; 673 struct drbd_conf *mdev; 674 675 /* if local IO is not allowed, will be NULL. 676 * if local IO _is_ allowed, holds the locally submitted bio clone, 677 * or, after local IO completion, the ERR_PTR(error). 678 * see drbd_endio_pri(). */ 679 struct bio *private_bio; 680 681 struct hlist_node colision; 682 sector_t sector; 683 unsigned int size; 684 unsigned int epoch; /* barrier_nr */ 685 686 /* barrier_nr: used to check on "completion" whether this req was in 687 * the current epoch, and we therefore have to close it, 688 * starting a new epoch... 689 */ 690 691 /* up to here, the struct layout is identical to drbd_epoch_entry; 692 * we might be able to use that to our advantage... */ 693 694 struct list_head tl_requests; /* ring list in the transfer log */ 695 struct bio *master_bio; /* master bio pointer */ 696 unsigned long rq_state; /* see comments above _req_mod() */ 697 int seq_num; 698 unsigned long start_time; 699 }; 700 701 struct drbd_tl_epoch { 702 struct drbd_work w; 703 struct list_head requests; /* requests before */ 704 struct drbd_tl_epoch *next; /* pointer to the next barrier */ 705 unsigned int br_number; /* the barriers identifier. */ 706 int n_req; /* number of requests attached before this barrier */ 707 }; 708 709 struct drbd_request; 710 711 /* These Tl_epoch_entries may be in one of 6 lists: 712 active_ee .. data packet being written 713 sync_ee .. syncer block being written 714 done_ee .. block written, need to send P_WRITE_ACK 715 read_ee .. [RS]P_DATA_REQUEST being read 716 */ 717 718 struct drbd_epoch { 719 struct list_head list; 720 unsigned int barrier_nr; 721 atomic_t epoch_size; /* increased on every request added. */ 722 atomic_t active; /* increased on every req. added, and dec on every finished. */ 723 unsigned long flags; 724 }; 725 726 /* drbd_epoch flag bits */ 727 enum { 728 DE_BARRIER_IN_NEXT_EPOCH_ISSUED, 729 DE_BARRIER_IN_NEXT_EPOCH_DONE, 730 DE_CONTAINS_A_BARRIER, 731 DE_HAVE_BARRIER_NUMBER, 732 DE_IS_FINISHING, 733 }; 734 735 enum epoch_event { 736 EV_PUT, 737 EV_GOT_BARRIER_NR, 738 EV_BARRIER_DONE, 739 EV_BECAME_LAST, 740 EV_CLEANUP = 32, /* used as flag */ 741 }; 742 743 struct drbd_wq_barrier { 744 struct drbd_work w; 745 struct completion done; 746 }; 747 748 struct digest_info { 749 int digest_size; 750 void *digest; 751 }; 752 753 struct drbd_epoch_entry { 754 struct drbd_work w; 755 struct hlist_node colision; 756 struct drbd_epoch *epoch; 757 struct drbd_conf *mdev; 758 struct page *pages; 759 atomic_t pending_bios; 760 unsigned int size; 761 /* see comments on ee flag bits below */ 762 unsigned long flags; 763 sector_t sector; 764 u64 block_id; 765 }; 766 767 /* ee flag bits. 768 * While corresponding bios are in flight, the only modification will be 769 * set_bit WAS_ERROR, which has to be atomic. 770 * If no bios are in flight yet, or all have been completed, 771 * non-atomic modification to ee->flags is ok. 772 */ 773 enum { 774 __EE_CALL_AL_COMPLETE_IO, 775 __EE_MAY_SET_IN_SYNC, 776 777 /* This epoch entry closes an epoch using a barrier. 778 * On sucessful completion, the epoch is released, 779 * and the P_BARRIER_ACK send. */ 780 __EE_IS_BARRIER, 781 782 /* In case a barrier failed, 783 * we need to resubmit without the barrier flag. */ 784 __EE_RESUBMITTED, 785 786 /* we may have several bios per epoch entry. 787 * if any of those fail, we set this flag atomically 788 * from the endio callback */ 789 __EE_WAS_ERROR, 790 }; 791 #define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO) 792 #define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC) 793 #define EE_IS_BARRIER (1<<__EE_IS_BARRIER) 794 #define EE_RESUBMITTED (1<<__EE_RESUBMITTED) 795 #define EE_WAS_ERROR (1<<__EE_WAS_ERROR) 796 797 /* global flag bits */ 798 enum { 799 CREATE_BARRIER, /* next P_DATA is preceeded by a P_BARRIER */ 800 SIGNAL_ASENDER, /* whether asender wants to be interrupted */ 801 SEND_PING, /* whether asender should send a ping asap */ 802 803 STOP_SYNC_TIMER, /* tell timer to cancel itself */ 804 UNPLUG_QUEUED, /* only relevant with kernel 2.4 */ 805 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */ 806 MD_DIRTY, /* current uuids and flags not yet on disk */ 807 DISCARD_CONCURRENT, /* Set on one node, cleared on the peer! */ 808 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */ 809 CLUSTER_ST_CHANGE, /* Cluster wide state change going on... */ 810 CL_ST_CHG_SUCCESS, 811 CL_ST_CHG_FAIL, 812 CRASHED_PRIMARY, /* This node was a crashed primary. 813 * Gets cleared when the state.conn 814 * goes into C_CONNECTED state. */ 815 WRITE_BM_AFTER_RESYNC, /* A kmalloc() during resync failed */ 816 NO_BARRIER_SUPP, /* underlying block device doesn't implement barriers */ 817 CONSIDER_RESYNC, 818 819 MD_NO_BARRIER, /* meta data device does not support barriers, 820 so don't even try */ 821 SUSPEND_IO, /* suspend application io */ 822 BITMAP_IO, /* suspend application io; 823 once no more io in flight, start bitmap io */ 824 BITMAP_IO_QUEUED, /* Started bitmap IO */ 825 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */ 826 NET_CONGESTED, /* The data socket is congested */ 827 828 CONFIG_PENDING, /* serialization of (re)configuration requests. 829 * if set, also prevents the device from dying */ 830 DEVICE_DYING, /* device became unconfigured, 831 * but worker thread is still handling the cleanup. 832 * reconfiguring (nl_disk_conf, nl_net_conf) is dissalowed, 833 * while this is set. */ 834 RESIZE_PENDING, /* Size change detected locally, waiting for the response from 835 * the peer, if it changed there as well. */ 836 CONN_DRY_RUN, /* Expect disconnect after resync handshake. */ 837 GOT_PING_ACK, /* set when we receive a ping_ack packet, misc wait gets woken */ 838 }; 839 840 struct drbd_bitmap; /* opaque for drbd_conf */ 841 842 /* TODO sort members for performance 843 * MAYBE group them further */ 844 845 /* THINK maybe we actually want to use the default "event/%s" worker threads 846 * or similar in linux 2.6, which uses per cpu data and threads. 847 * 848 * To be general, this might need a spin_lock member. 849 * For now, please use the mdev->req_lock to protect list_head, 850 * see drbd_queue_work below. 851 */ 852 struct drbd_work_queue { 853 struct list_head q; 854 struct semaphore s; /* producers up it, worker down()s it */ 855 spinlock_t q_lock; /* to protect the list. */ 856 }; 857 858 struct drbd_socket { 859 struct drbd_work_queue work; 860 struct mutex mutex; 861 struct socket *socket; 862 /* this way we get our 863 * send/receive buffers off the stack */ 864 union p_polymorph sbuf; 865 union p_polymorph rbuf; 866 }; 867 868 struct drbd_md { 869 u64 md_offset; /* sector offset to 'super' block */ 870 871 u64 la_size_sect; /* last agreed size, unit sectors */ 872 u64 uuid[UI_SIZE]; 873 u64 device_uuid; 874 u32 flags; 875 u32 md_size_sect; 876 877 s32 al_offset; /* signed relative sector offset to al area */ 878 s32 bm_offset; /* signed relative sector offset to bitmap */ 879 880 /* u32 al_nr_extents; important for restoring the AL 881 * is stored into sync_conf.al_extents, which in turn 882 * gets applied to act_log->nr_elements 883 */ 884 }; 885 886 /* for sync_conf and other types... */ 887 #define NL_PACKET(name, number, fields) struct name { fields }; 888 #define NL_INTEGER(pn,pr,member) int member; 889 #define NL_INT64(pn,pr,member) __u64 member; 890 #define NL_BIT(pn,pr,member) unsigned member:1; 891 #define NL_STRING(pn,pr,member,len) unsigned char member[len]; int member ## _len; 892 #include "linux/drbd_nl.h" 893 894 struct drbd_backing_dev { 895 struct block_device *backing_bdev; 896 struct block_device *md_bdev; 897 struct file *lo_file; 898 struct file *md_file; 899 struct drbd_md md; 900 struct disk_conf dc; /* The user provided config... */ 901 sector_t known_size; /* last known size of that backing device */ 902 }; 903 904 struct drbd_md_io { 905 struct drbd_conf *mdev; 906 struct completion event; 907 int error; 908 }; 909 910 struct bm_io_work { 911 struct drbd_work w; 912 char *why; 913 int (*io_fn)(struct drbd_conf *mdev); 914 void (*done)(struct drbd_conf *mdev, int rv); 915 }; 916 917 enum write_ordering_e { 918 WO_none, 919 WO_drain_io, 920 WO_bdev_flush, 921 WO_bio_barrier 922 }; 923 924 struct drbd_conf { 925 /* things that are stored as / read from meta data on disk */ 926 unsigned long flags; 927 928 /* configured by drbdsetup */ 929 struct net_conf *net_conf; /* protected by get_net_conf() and put_net_conf() */ 930 struct syncer_conf sync_conf; 931 struct drbd_backing_dev *ldev __protected_by(local); 932 933 sector_t p_size; /* partner's disk size */ 934 struct request_queue *rq_queue; 935 struct block_device *this_bdev; 936 struct gendisk *vdisk; 937 938 struct drbd_socket data; /* data/barrier/cstate/parameter packets */ 939 struct drbd_socket meta; /* ping/ack (metadata) packets */ 940 int agreed_pro_version; /* actually used protocol version */ 941 unsigned long last_received; /* in jiffies, either socket */ 942 unsigned int ko_count; 943 struct drbd_work resync_work, 944 unplug_work, 945 md_sync_work, 946 delay_probe_work, 947 uuid_work; 948 struct timer_list resync_timer; 949 struct timer_list md_sync_timer; 950 struct timer_list delay_probe_timer; 951 952 /* Used after attach while negotiating new disk state. */ 953 union drbd_state new_state_tmp; 954 955 union drbd_state state; 956 wait_queue_head_t misc_wait; 957 wait_queue_head_t state_wait; /* upon each state change. */ 958 unsigned int send_cnt; 959 unsigned int recv_cnt; 960 unsigned int read_cnt; 961 unsigned int writ_cnt; 962 unsigned int al_writ_cnt; 963 unsigned int bm_writ_cnt; 964 atomic_t ap_bio_cnt; /* Requests we need to complete */ 965 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */ 966 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */ 967 atomic_t unacked_cnt; /* Need to send replys for */ 968 atomic_t local_cnt; /* Waiting for local completion */ 969 atomic_t net_cnt; /* Users of net_conf */ 970 spinlock_t req_lock; 971 struct drbd_tl_epoch *unused_spare_tle; /* for pre-allocation */ 972 struct drbd_tl_epoch *newest_tle; 973 struct drbd_tl_epoch *oldest_tle; 974 struct list_head out_of_sequence_requests; 975 struct hlist_head *tl_hash; 976 unsigned int tl_hash_s; 977 978 /* blocks to sync in this run [unit BM_BLOCK_SIZE] */ 979 unsigned long rs_total; 980 /* number of sync IOs that failed in this run */ 981 unsigned long rs_failed; 982 /* Syncer's start time [unit jiffies] */ 983 unsigned long rs_start; 984 /* cumulated time in PausedSyncX state [unit jiffies] */ 985 unsigned long rs_paused; 986 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */ 987 unsigned long rs_mark_left; 988 /* marks's time [unit jiffies] */ 989 unsigned long rs_mark_time; 990 /* skipped because csum was equeal [unit BM_BLOCK_SIZE] */ 991 unsigned long rs_same_csum; 992 993 /* where does the admin want us to start? (sector) */ 994 sector_t ov_start_sector; 995 /* where are we now? (sector) */ 996 sector_t ov_position; 997 /* Start sector of out of sync range (to merge printk reporting). */ 998 sector_t ov_last_oos_start; 999 /* size of out-of-sync range in sectors. */ 1000 sector_t ov_last_oos_size; 1001 unsigned long ov_left; /* in bits */ 1002 struct crypto_hash *csums_tfm; 1003 struct crypto_hash *verify_tfm; 1004 1005 struct drbd_thread receiver; 1006 struct drbd_thread worker; 1007 struct drbd_thread asender; 1008 struct drbd_bitmap *bitmap; 1009 unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */ 1010 1011 /* Used to track operations of resync... */ 1012 struct lru_cache *resync; 1013 /* Number of locked elements in resync LRU */ 1014 unsigned int resync_locked; 1015 /* resync extent number waiting for application requests */ 1016 unsigned int resync_wenr; 1017 1018 int open_cnt; 1019 u64 *p_uuid; 1020 struct drbd_epoch *current_epoch; 1021 spinlock_t epoch_lock; 1022 unsigned int epochs; 1023 enum write_ordering_e write_ordering; 1024 struct list_head active_ee; /* IO in progress */ 1025 struct list_head sync_ee; /* IO in progress */ 1026 struct list_head done_ee; /* send ack */ 1027 struct list_head read_ee; /* IO in progress */ 1028 struct list_head net_ee; /* zero-copy network send in progress */ 1029 struct hlist_head *ee_hash; /* is proteced by req_lock! */ 1030 unsigned int ee_hash_s; 1031 1032 /* this one is protected by ee_lock, single thread */ 1033 struct drbd_epoch_entry *last_write_w_barrier; 1034 1035 int next_barrier_nr; 1036 struct hlist_head *app_reads_hash; /* is proteced by req_lock */ 1037 struct list_head resync_reads; 1038 atomic_t pp_in_use; 1039 wait_queue_head_t ee_wait; 1040 struct page *md_io_page; /* one page buffer for md_io */ 1041 struct page *md_io_tmpp; /* for logical_block_size != 512 */ 1042 struct mutex md_io_mutex; /* protects the md_io_buffer */ 1043 spinlock_t al_lock; 1044 wait_queue_head_t al_wait; 1045 struct lru_cache *act_log; /* activity log */ 1046 unsigned int al_tr_number; 1047 int al_tr_cycle; 1048 int al_tr_pos; /* position of the next transaction in the journal */ 1049 struct crypto_hash *cram_hmac_tfm; 1050 struct crypto_hash *integrity_w_tfm; /* to be used by the worker thread */ 1051 struct crypto_hash *integrity_r_tfm; /* to be used by the receiver thread */ 1052 void *int_dig_out; 1053 void *int_dig_in; 1054 void *int_dig_vv; 1055 wait_queue_head_t seq_wait; 1056 atomic_t packet_seq; 1057 unsigned int peer_seq; 1058 spinlock_t peer_seq_lock; 1059 unsigned int minor; 1060 unsigned long comm_bm_set; /* communicated number of set bits. */ 1061 cpumask_var_t cpu_mask; 1062 struct bm_io_work bm_io_work; 1063 u64 ed_uuid; /* UUID of the exposed data */ 1064 struct mutex state_mutex; 1065 char congestion_reason; /* Why we where congested... */ 1066 struct list_head delay_probes; /* protected by peer_seq_lock */ 1067 int data_delay; /* Delay of packets on the data-sock behind meta-sock */ 1068 unsigned int delay_seq; /* To generate sequence numbers of delay probes */ 1069 struct timeval dps_time; /* delay-probes-start-time */ 1070 unsigned int dp_volume_last; /* send_cnt of last delay probe */ 1071 int c_sync_rate; /* current resync rate after delay_probe magic */ 1072 atomic_t new_c_uuid; 1073 }; 1074 1075 static inline struct drbd_conf *minor_to_mdev(unsigned int minor) 1076 { 1077 struct drbd_conf *mdev; 1078 1079 mdev = minor < minor_count ? minor_table[minor] : NULL; 1080 1081 return mdev; 1082 } 1083 1084 static inline unsigned int mdev_to_minor(struct drbd_conf *mdev) 1085 { 1086 return mdev->minor; 1087 } 1088 1089 /* returns 1 if it was successfull, 1090 * returns 0 if there was no data socket. 1091 * so wherever you are going to use the data.socket, e.g. do 1092 * if (!drbd_get_data_sock(mdev)) 1093 * return 0; 1094 * CODE(); 1095 * drbd_put_data_sock(mdev); 1096 */ 1097 static inline int drbd_get_data_sock(struct drbd_conf *mdev) 1098 { 1099 mutex_lock(&mdev->data.mutex); 1100 /* drbd_disconnect() could have called drbd_free_sock() 1101 * while we were waiting in down()... */ 1102 if (unlikely(mdev->data.socket == NULL)) { 1103 mutex_unlock(&mdev->data.mutex); 1104 return 0; 1105 } 1106 return 1; 1107 } 1108 1109 static inline void drbd_put_data_sock(struct drbd_conf *mdev) 1110 { 1111 mutex_unlock(&mdev->data.mutex); 1112 } 1113 1114 /* 1115 * function declarations 1116 *************************/ 1117 1118 /* drbd_main.c */ 1119 1120 enum chg_state_flags { 1121 CS_HARD = 1, 1122 CS_VERBOSE = 2, 1123 CS_WAIT_COMPLETE = 4, 1124 CS_SERIALIZE = 8, 1125 CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE, 1126 }; 1127 1128 enum dds_flags { 1129 DDSF_FORCED = 1, 1130 DDSF_NO_RESYNC = 2, /* Do not run a resync for the new space */ 1131 }; 1132 1133 extern void drbd_init_set_defaults(struct drbd_conf *mdev); 1134 extern int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f, 1135 union drbd_state mask, union drbd_state val); 1136 extern void drbd_force_state(struct drbd_conf *, union drbd_state, 1137 union drbd_state); 1138 extern int _drbd_request_state(struct drbd_conf *, union drbd_state, 1139 union drbd_state, enum chg_state_flags); 1140 extern int __drbd_set_state(struct drbd_conf *, union drbd_state, 1141 enum chg_state_flags, struct completion *done); 1142 extern void print_st_err(struct drbd_conf *, union drbd_state, 1143 union drbd_state, int); 1144 extern int drbd_thread_start(struct drbd_thread *thi); 1145 extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait); 1146 #ifdef CONFIG_SMP 1147 extern void drbd_thread_current_set_cpu(struct drbd_conf *mdev); 1148 extern void drbd_calc_cpu_mask(struct drbd_conf *mdev); 1149 #else 1150 #define drbd_thread_current_set_cpu(A) ({}) 1151 #define drbd_calc_cpu_mask(A) ({}) 1152 #endif 1153 extern void drbd_free_resources(struct drbd_conf *mdev); 1154 extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr, 1155 unsigned int set_size); 1156 extern void tl_clear(struct drbd_conf *mdev); 1157 extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *); 1158 extern void drbd_free_sock(struct drbd_conf *mdev); 1159 extern int drbd_send(struct drbd_conf *mdev, struct socket *sock, 1160 void *buf, size_t size, unsigned msg_flags); 1161 extern int drbd_send_protocol(struct drbd_conf *mdev); 1162 extern int drbd_send_uuids(struct drbd_conf *mdev); 1163 extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev); 1164 extern int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val); 1165 extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags); 1166 extern int _drbd_send_state(struct drbd_conf *mdev); 1167 extern int drbd_send_state(struct drbd_conf *mdev); 1168 extern int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock, 1169 enum drbd_packets cmd, struct p_header *h, 1170 size_t size, unsigned msg_flags); 1171 #define USE_DATA_SOCKET 1 1172 #define USE_META_SOCKET 0 1173 extern int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket, 1174 enum drbd_packets cmd, struct p_header *h, 1175 size_t size); 1176 extern int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, 1177 char *data, size_t size); 1178 extern int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc); 1179 extern int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, 1180 u32 set_size); 1181 extern int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd, 1182 struct drbd_epoch_entry *e); 1183 extern int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd, 1184 struct p_block_req *rp); 1185 extern int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd, 1186 struct p_data *dp); 1187 extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd, 1188 sector_t sector, int blksize, u64 block_id); 1189 extern int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd, 1190 struct drbd_epoch_entry *e); 1191 extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req); 1192 extern int _drbd_send_barrier(struct drbd_conf *mdev, 1193 struct drbd_tl_epoch *barrier); 1194 extern int drbd_send_drequest(struct drbd_conf *mdev, int cmd, 1195 sector_t sector, int size, u64 block_id); 1196 extern int drbd_send_drequest_csum(struct drbd_conf *mdev, 1197 sector_t sector,int size, 1198 void *digest, int digest_size, 1199 enum drbd_packets cmd); 1200 extern int drbd_send_ov_request(struct drbd_conf *mdev,sector_t sector,int size); 1201 1202 extern int drbd_send_bitmap(struct drbd_conf *mdev); 1203 extern int _drbd_send_bitmap(struct drbd_conf *mdev); 1204 extern int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode); 1205 extern void drbd_free_bc(struct drbd_backing_dev *ldev); 1206 extern void drbd_mdev_cleanup(struct drbd_conf *mdev); 1207 1208 /* drbd_meta-data.c (still in drbd_main.c) */ 1209 extern void drbd_md_sync(struct drbd_conf *mdev); 1210 extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev); 1211 /* maybe define them below as inline? */ 1212 extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1213 extern void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1214 extern void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1215 extern void _drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1216 extern void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local); 1217 extern void drbd_md_set_flag(struct drbd_conf *mdev, int flags) __must_hold(local); 1218 extern void drbd_md_clear_flag(struct drbd_conf *mdev, int flags)__must_hold(local); 1219 extern int drbd_md_test_flag(struct drbd_backing_dev *, int); 1220 extern void drbd_md_mark_dirty(struct drbd_conf *mdev); 1221 extern void drbd_queue_bitmap_io(struct drbd_conf *mdev, 1222 int (*io_fn)(struct drbd_conf *), 1223 void (*done)(struct drbd_conf *, int), 1224 char *why); 1225 extern int drbd_bmio_set_n_write(struct drbd_conf *mdev); 1226 extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev); 1227 extern int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why); 1228 1229 1230 /* Meta data layout 1231 We reserve a 128MB Block (4k aligned) 1232 * either at the end of the backing device 1233 * or on a separate meta data device. */ 1234 1235 #define MD_RESERVED_SECT (128LU << 11) /* 128 MB, unit sectors */ 1236 /* The following numbers are sectors */ 1237 #define MD_AL_OFFSET 8 /* 8 Sectors after start of meta area */ 1238 #define MD_AL_MAX_SIZE 64 /* = 32 kb LOG ~ 3776 extents ~ 14 GB Storage */ 1239 /* Allows up to about 3.8TB */ 1240 #define MD_BM_OFFSET (MD_AL_OFFSET + MD_AL_MAX_SIZE) 1241 1242 /* Since the smalles IO unit is usually 512 byte */ 1243 #define MD_SECTOR_SHIFT 9 1244 #define MD_SECTOR_SIZE (1<<MD_SECTOR_SHIFT) 1245 1246 /* activity log */ 1247 #define AL_EXTENTS_PT ((MD_SECTOR_SIZE-12)/8-1) /* 61 ; Extents per 512B sector */ 1248 #define AL_EXTENT_SHIFT 22 /* One extent represents 4M Storage */ 1249 #define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT) 1250 1251 #if BITS_PER_LONG == 32 1252 #define LN2_BPL 5 1253 #define cpu_to_lel(A) cpu_to_le32(A) 1254 #define lel_to_cpu(A) le32_to_cpu(A) 1255 #elif BITS_PER_LONG == 64 1256 #define LN2_BPL 6 1257 #define cpu_to_lel(A) cpu_to_le64(A) 1258 #define lel_to_cpu(A) le64_to_cpu(A) 1259 #else 1260 #error "LN2 of BITS_PER_LONG unknown!" 1261 #endif 1262 1263 /* resync bitmap */ 1264 /* 16MB sized 'bitmap extent' to track syncer usage */ 1265 struct bm_extent { 1266 int rs_left; /* number of bits set (out of sync) in this extent. */ 1267 int rs_failed; /* number of failed resync requests in this extent. */ 1268 unsigned long flags; 1269 struct lc_element lce; 1270 }; 1271 1272 #define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */ 1273 #define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */ 1274 1275 /* drbd_bitmap.c */ 1276 /* 1277 * We need to store one bit for a block. 1278 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap. 1279 * Bit 0 ==> local node thinks this block is binary identical on both nodes 1280 * Bit 1 ==> local node thinks this block needs to be synced. 1281 */ 1282 1283 #define BM_BLOCK_SHIFT 12 /* 4k per bit */ 1284 #define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT) 1285 /* (9+3) : 512 bytes @ 8 bits; representing 16M storage 1286 * per sector of on disk bitmap */ 1287 #define BM_EXT_SHIFT (BM_BLOCK_SHIFT + MD_SECTOR_SHIFT + 3) /* = 24 */ 1288 #define BM_EXT_SIZE (1<<BM_EXT_SHIFT) 1289 1290 #if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12) 1291 #error "HAVE YOU FIXED drbdmeta AS WELL??" 1292 #endif 1293 1294 /* thus many _storage_ sectors are described by one bit */ 1295 #define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9)) 1296 #define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9)) 1297 #define BM_SECT_PER_BIT BM_BIT_TO_SECT(1) 1298 1299 /* bit to represented kilo byte conversion */ 1300 #define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10)) 1301 1302 /* in which _bitmap_ extent (resp. sector) the bit for a certain 1303 * _storage_ sector is located in */ 1304 #define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9)) 1305 1306 /* how much _storage_ sectors we have per bitmap sector */ 1307 #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9)) 1308 #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1) 1309 1310 /* in one sector of the bitmap, we have this many activity_log extents. */ 1311 #define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT)) 1312 #define BM_WORDS_PER_AL_EXT (1 << (AL_EXTENT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL)) 1313 1314 #define BM_BLOCKS_PER_BM_EXT_B (BM_EXT_SHIFT - BM_BLOCK_SHIFT) 1315 #define BM_BLOCKS_PER_BM_EXT_MASK ((1<<BM_BLOCKS_PER_BM_EXT_B) - 1) 1316 1317 /* the extent in "PER_EXTENT" below is an activity log extent 1318 * we need that many (long words/bytes) to store the bitmap 1319 * of one AL_EXTENT_SIZE chunk of storage. 1320 * we can store the bitmap for that many AL_EXTENTS within 1321 * one sector of the _on_disk_ bitmap: 1322 * bit 0 bit 37 bit 38 bit (512*8)-1 1323 * ...|........|........|.. // ..|........| 1324 * sect. 0 `296 `304 ^(512*8*8)-1 1325 * 1326 #define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG ) 1327 #define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128 1328 #define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4 1329 */ 1330 1331 #define DRBD_MAX_SECTORS_32 (0xffffffffLU) 1332 #define DRBD_MAX_SECTORS_BM \ 1333 ((MD_RESERVED_SECT - MD_BM_OFFSET) * (1LL<<(BM_EXT_SHIFT-9))) 1334 #if DRBD_MAX_SECTORS_BM < DRBD_MAX_SECTORS_32 1335 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1336 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_BM 1337 #elif !defined(CONFIG_LBDAF) && BITS_PER_LONG == 32 1338 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_32 1339 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_32 1340 #else 1341 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1342 /* 16 TB in units of sectors */ 1343 #if BITS_PER_LONG == 32 1344 /* adjust by one page worth of bitmap, 1345 * so we won't wrap around in drbd_bm_find_next_bit. 1346 * you should use 64bit OS for that much storage, anyways. */ 1347 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff) 1348 #else 1349 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0x1LU << 32) 1350 #endif 1351 #endif 1352 1353 /* Sector shift value for the "hash" functions of tl_hash and ee_hash tables. 1354 * With a value of 6 all IO in one 32K block make it to the same slot of the 1355 * hash table. */ 1356 #define HT_SHIFT 6 1357 #define DRBD_MAX_SEGMENT_SIZE (1U<<(9+HT_SHIFT)) 1358 1359 /* Number of elements in the app_reads_hash */ 1360 #define APP_R_HSIZE 15 1361 1362 extern int drbd_bm_init(struct drbd_conf *mdev); 1363 extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors, int set_new_bits); 1364 extern void drbd_bm_cleanup(struct drbd_conf *mdev); 1365 extern void drbd_bm_set_all(struct drbd_conf *mdev); 1366 extern void drbd_bm_clear_all(struct drbd_conf *mdev); 1367 extern int drbd_bm_set_bits( 1368 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1369 extern int drbd_bm_clear_bits( 1370 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1371 /* bm_set_bits variant for use while holding drbd_bm_lock */ 1372 extern void _drbd_bm_set_bits(struct drbd_conf *mdev, 1373 const unsigned long s, const unsigned long e); 1374 extern int drbd_bm_test_bit(struct drbd_conf *mdev, unsigned long bitnr); 1375 extern int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr); 1376 extern int drbd_bm_write_sect(struct drbd_conf *mdev, unsigned long enr) __must_hold(local); 1377 extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local); 1378 extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local); 1379 extern unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev, 1380 unsigned long al_enr); 1381 extern size_t drbd_bm_words(struct drbd_conf *mdev); 1382 extern unsigned long drbd_bm_bits(struct drbd_conf *mdev); 1383 extern sector_t drbd_bm_capacity(struct drbd_conf *mdev); 1384 extern unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1385 /* bm_find_next variants for use while you hold drbd_bm_lock() */ 1386 extern unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1387 extern unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo); 1388 extern unsigned long drbd_bm_total_weight(struct drbd_conf *mdev); 1389 extern int drbd_bm_rs_done(struct drbd_conf *mdev); 1390 /* for receive_bitmap */ 1391 extern void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset, 1392 size_t number, unsigned long *buffer); 1393 /* for _drbd_send_bitmap and drbd_bm_write_sect */ 1394 extern void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset, 1395 size_t number, unsigned long *buffer); 1396 1397 extern void drbd_bm_lock(struct drbd_conf *mdev, char *why); 1398 extern void drbd_bm_unlock(struct drbd_conf *mdev); 1399 1400 extern int drbd_bm_count_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e); 1401 /* drbd_main.c */ 1402 1403 extern struct kmem_cache *drbd_request_cache; 1404 extern struct kmem_cache *drbd_ee_cache; /* epoch entries */ 1405 extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 1406 extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 1407 extern mempool_t *drbd_request_mempool; 1408 extern mempool_t *drbd_ee_mempool; 1409 1410 extern struct page *drbd_pp_pool; /* drbd's page pool */ 1411 extern spinlock_t drbd_pp_lock; 1412 extern int drbd_pp_vacant; 1413 extern wait_queue_head_t drbd_pp_wait; 1414 1415 extern rwlock_t global_state_lock; 1416 1417 extern struct drbd_conf *drbd_new_device(unsigned int minor); 1418 extern void drbd_free_mdev(struct drbd_conf *mdev); 1419 1420 extern int proc_details; 1421 1422 /* drbd_req */ 1423 extern int drbd_make_request_26(struct request_queue *q, struct bio *bio); 1424 extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req); 1425 extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec); 1426 extern int is_valid_ar_handle(struct drbd_request *, sector_t); 1427 1428 1429 /* drbd_nl.c */ 1430 extern void drbd_suspend_io(struct drbd_conf *mdev); 1431 extern void drbd_resume_io(struct drbd_conf *mdev); 1432 extern char *ppsize(char *buf, unsigned long long size); 1433 extern sector_t drbd_new_dev_size(struct drbd_conf *, struct drbd_backing_dev *, int); 1434 enum determine_dev_size { dev_size_error = -1, unchanged = 0, shrunk = 1, grew = 2 }; 1435 extern enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *, enum dds_flags) __must_hold(local); 1436 extern void resync_after_online_grow(struct drbd_conf *); 1437 extern void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int) __must_hold(local); 1438 extern int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, 1439 int force); 1440 enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev); 1441 extern int drbd_khelper(struct drbd_conf *mdev, char *cmd); 1442 1443 /* drbd_worker.c */ 1444 extern int drbd_worker(struct drbd_thread *thi); 1445 extern int drbd_alter_sa(struct drbd_conf *mdev, int na); 1446 extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side); 1447 extern void resume_next_sg(struct drbd_conf *mdev); 1448 extern void suspend_other_sg(struct drbd_conf *mdev); 1449 extern int drbd_resync_finished(struct drbd_conf *mdev); 1450 /* maybe rather drbd_main.c ? */ 1451 extern int drbd_md_sync_page_io(struct drbd_conf *mdev, 1452 struct drbd_backing_dev *bdev, sector_t sector, int rw); 1453 extern void drbd_ov_oos_found(struct drbd_conf*, sector_t, int); 1454 1455 static inline void ov_oos_print(struct drbd_conf *mdev) 1456 { 1457 if (mdev->ov_last_oos_size) { 1458 dev_err(DEV, "Out of sync: start=%llu, size=%lu (sectors)\n", 1459 (unsigned long long)mdev->ov_last_oos_start, 1460 (unsigned long)mdev->ov_last_oos_size); 1461 } 1462 mdev->ov_last_oos_size=0; 1463 } 1464 1465 1466 extern void drbd_csum_bio(struct drbd_conf *, struct crypto_hash *, struct bio *, void *); 1467 extern void drbd_csum_ee(struct drbd_conf *, struct crypto_hash *, struct drbd_epoch_entry *, void *); 1468 /* worker callbacks */ 1469 extern int w_req_cancel_conflict(struct drbd_conf *, struct drbd_work *, int); 1470 extern int w_read_retry_remote(struct drbd_conf *, struct drbd_work *, int); 1471 extern int w_e_end_data_req(struct drbd_conf *, struct drbd_work *, int); 1472 extern int w_e_end_rsdata_req(struct drbd_conf *, struct drbd_work *, int); 1473 extern int w_e_end_csum_rs_req(struct drbd_conf *, struct drbd_work *, int); 1474 extern int w_e_end_ov_reply(struct drbd_conf *, struct drbd_work *, int); 1475 extern int w_e_end_ov_req(struct drbd_conf *, struct drbd_work *, int); 1476 extern int w_ov_finished(struct drbd_conf *, struct drbd_work *, int); 1477 extern int w_resync_inactive(struct drbd_conf *, struct drbd_work *, int); 1478 extern int w_resume_next_sg(struct drbd_conf *, struct drbd_work *, int); 1479 extern int w_io_error(struct drbd_conf *, struct drbd_work *, int); 1480 extern int w_send_write_hint(struct drbd_conf *, struct drbd_work *, int); 1481 extern int w_make_resync_request(struct drbd_conf *, struct drbd_work *, int); 1482 extern int w_send_dblock(struct drbd_conf *, struct drbd_work *, int); 1483 extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int); 1484 extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int); 1485 extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int); 1486 extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int); 1487 1488 extern void resync_timer_fn(unsigned long data); 1489 1490 /* drbd_receiver.c */ 1491 extern int drbd_submit_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, 1492 const unsigned rw, const int fault_type); 1493 extern int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list); 1494 extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev, 1495 u64 id, 1496 sector_t sector, 1497 unsigned int data_size, 1498 gfp_t gfp_mask) __must_hold(local); 1499 extern void drbd_free_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e); 1500 extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1501 struct list_head *head); 1502 extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1503 struct list_head *head); 1504 extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled); 1505 extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed); 1506 extern void drbd_flush_workqueue(struct drbd_conf *mdev); 1507 1508 /* yes, there is kernel_setsockopt, but only since 2.6.18. we don't need to 1509 * mess with get_fs/set_fs, we know we are KERNEL_DS always. */ 1510 static inline int drbd_setsockopt(struct socket *sock, int level, int optname, 1511 char __user *optval, int optlen) 1512 { 1513 int err; 1514 if (level == SOL_SOCKET) 1515 err = sock_setsockopt(sock, level, optname, optval, optlen); 1516 else 1517 err = sock->ops->setsockopt(sock, level, optname, optval, 1518 optlen); 1519 return err; 1520 } 1521 1522 static inline void drbd_tcp_cork(struct socket *sock) 1523 { 1524 int __user val = 1; 1525 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1526 (char __user *)&val, sizeof(val)); 1527 } 1528 1529 static inline void drbd_tcp_uncork(struct socket *sock) 1530 { 1531 int __user val = 0; 1532 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1533 (char __user *)&val, sizeof(val)); 1534 } 1535 1536 static inline void drbd_tcp_nodelay(struct socket *sock) 1537 { 1538 int __user val = 1; 1539 (void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY, 1540 (char __user *)&val, sizeof(val)); 1541 } 1542 1543 static inline void drbd_tcp_quickack(struct socket *sock) 1544 { 1545 int __user val = 1; 1546 (void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK, 1547 (char __user *)&val, sizeof(val)); 1548 } 1549 1550 void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo); 1551 1552 /* drbd_proc.c */ 1553 extern struct proc_dir_entry *drbd_proc; 1554 extern const struct file_operations drbd_proc_fops; 1555 extern const char *drbd_conn_str(enum drbd_conns s); 1556 extern const char *drbd_role_str(enum drbd_role s); 1557 1558 /* drbd_actlog.c */ 1559 extern void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector); 1560 extern void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector); 1561 extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector); 1562 extern int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1563 extern int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1564 extern void drbd_rs_cancel_all(struct drbd_conf *mdev); 1565 extern int drbd_rs_del_all(struct drbd_conf *mdev); 1566 extern void drbd_rs_failed_io(struct drbd_conf *mdev, 1567 sector_t sector, int size); 1568 extern int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *); 1569 extern void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector, 1570 int size, const char *file, const unsigned int line); 1571 #define drbd_set_in_sync(mdev, sector, size) \ 1572 __drbd_set_in_sync(mdev, sector, size, __FILE__, __LINE__) 1573 extern void __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector, 1574 int size, const char *file, const unsigned int line); 1575 #define drbd_set_out_of_sync(mdev, sector, size) \ 1576 __drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__) 1577 extern void drbd_al_apply_to_bm(struct drbd_conf *mdev); 1578 extern void drbd_al_to_on_disk_bm(struct drbd_conf *mdev); 1579 extern void drbd_al_shrink(struct drbd_conf *mdev); 1580 1581 1582 /* drbd_nl.c */ 1583 1584 void drbd_nl_cleanup(void); 1585 int __init drbd_nl_init(void); 1586 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state); 1587 void drbd_bcast_sync_progress(struct drbd_conf *mdev); 1588 void drbd_bcast_ee(struct drbd_conf *mdev, 1589 const char *reason, const int dgs, 1590 const char* seen_hash, const char* calc_hash, 1591 const struct drbd_epoch_entry* e); 1592 1593 1594 /** 1595 * DOC: DRBD State macros 1596 * 1597 * These macros are used to express state changes in easily readable form. 1598 * 1599 * The NS macros expand to a mask and a value, that can be bit ored onto the 1600 * current state as soon as the spinlock (req_lock) was taken. 1601 * 1602 * The _NS macros are used for state functions that get called with the 1603 * spinlock. These macros expand directly to the new state value. 1604 * 1605 * Besides the basic forms NS() and _NS() additional _?NS[23] are defined 1606 * to express state changes that affect more than one aspect of the state. 1607 * 1608 * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY) 1609 * Means that the network connection was established and that the peer 1610 * is in secondary role. 1611 */ 1612 #define role_MASK R_MASK 1613 #define peer_MASK R_MASK 1614 #define disk_MASK D_MASK 1615 #define pdsk_MASK D_MASK 1616 #define conn_MASK C_MASK 1617 #define susp_MASK 1 1618 #define user_isp_MASK 1 1619 #define aftr_isp_MASK 1 1620 1621 #define NS(T, S) \ 1622 ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \ 1623 ({ union drbd_state val; val.i = 0; val.T = (S); val; }) 1624 #define NS2(T1, S1, T2, S2) \ 1625 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1626 mask.T2 = T2##_MASK; mask; }), \ 1627 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1628 val.T2 = (S2); val; }) 1629 #define NS3(T1, S1, T2, S2, T3, S3) \ 1630 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1631 mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \ 1632 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1633 val.T2 = (S2); val.T3 = (S3); val; }) 1634 1635 #define _NS(D, T, S) \ 1636 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; }) 1637 #define _NS2(D, T1, S1, T2, S2) \ 1638 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1639 __ns.T2 = (S2); __ns; }) 1640 #define _NS3(D, T1, S1, T2, S2, T3, S3) \ 1641 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1642 __ns.T2 = (S2); __ns.T3 = (S3); __ns; }) 1643 1644 /* 1645 * inline helper functions 1646 *************************/ 1647 1648 /* see also page_chain_add and friends in drbd_receiver.c */ 1649 static inline struct page *page_chain_next(struct page *page) 1650 { 1651 return (struct page *)page_private(page); 1652 } 1653 #define page_chain_for_each(page) \ 1654 for (; page && ({ prefetch(page_chain_next(page)); 1; }); \ 1655 page = page_chain_next(page)) 1656 #define page_chain_for_each_safe(page, n) \ 1657 for (; page && ({ n = page_chain_next(page); 1; }); page = n) 1658 1659 static inline int drbd_bio_has_active_page(struct bio *bio) 1660 { 1661 struct bio_vec *bvec; 1662 int i; 1663 1664 __bio_for_each_segment(bvec, bio, i, 0) { 1665 if (page_count(bvec->bv_page) > 1) 1666 return 1; 1667 } 1668 1669 return 0; 1670 } 1671 1672 static inline int drbd_ee_has_active_page(struct drbd_epoch_entry *e) 1673 { 1674 struct page *page = e->pages; 1675 page_chain_for_each(page) { 1676 if (page_count(page) > 1) 1677 return 1; 1678 } 1679 return 0; 1680 } 1681 1682 1683 static inline void drbd_state_lock(struct drbd_conf *mdev) 1684 { 1685 wait_event(mdev->misc_wait, 1686 !test_and_set_bit(CLUSTER_ST_CHANGE, &mdev->flags)); 1687 } 1688 1689 static inline void drbd_state_unlock(struct drbd_conf *mdev) 1690 { 1691 clear_bit(CLUSTER_ST_CHANGE, &mdev->flags); 1692 wake_up(&mdev->misc_wait); 1693 } 1694 1695 static inline int _drbd_set_state(struct drbd_conf *mdev, 1696 union drbd_state ns, enum chg_state_flags flags, 1697 struct completion *done) 1698 { 1699 int rv; 1700 1701 read_lock(&global_state_lock); 1702 rv = __drbd_set_state(mdev, ns, flags, done); 1703 read_unlock(&global_state_lock); 1704 1705 return rv; 1706 } 1707 1708 /** 1709 * drbd_request_state() - Reqest a state change 1710 * @mdev: DRBD device. 1711 * @mask: mask of state bits to change. 1712 * @val: value of new state bits. 1713 * 1714 * This is the most graceful way of requesting a state change. It is verbose 1715 * quite verbose in case the state change is not possible, and all those 1716 * state changes are globally serialized. 1717 */ 1718 static inline int drbd_request_state(struct drbd_conf *mdev, 1719 union drbd_state mask, 1720 union drbd_state val) 1721 { 1722 return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED); 1723 } 1724 1725 #define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__) 1726 static inline void __drbd_chk_io_error_(struct drbd_conf *mdev, int forcedetach, const char *where) 1727 { 1728 switch (mdev->ldev->dc.on_io_error) { 1729 case EP_PASS_ON: 1730 if (!forcedetach) { 1731 if (printk_ratelimit()) 1732 dev_err(DEV, "Local IO failed in %s." 1733 "Passing error on...\n", where); 1734 break; 1735 } 1736 /* NOTE fall through to detach case if forcedetach set */ 1737 case EP_DETACH: 1738 case EP_CALL_HELPER: 1739 if (mdev->state.disk > D_FAILED) { 1740 _drbd_set_state(_NS(mdev, disk, D_FAILED), CS_HARD, NULL); 1741 dev_err(DEV, "Local IO failed in %s." 1742 "Detaching...\n", where); 1743 } 1744 break; 1745 } 1746 } 1747 1748 /** 1749 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers 1750 * @mdev: DRBD device. 1751 * @error: Error code passed to the IO completion callback 1752 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data 1753 * 1754 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED) 1755 */ 1756 #define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__) 1757 static inline void drbd_chk_io_error_(struct drbd_conf *mdev, 1758 int error, int forcedetach, const char *where) 1759 { 1760 if (error) { 1761 unsigned long flags; 1762 spin_lock_irqsave(&mdev->req_lock, flags); 1763 __drbd_chk_io_error_(mdev, forcedetach, where); 1764 spin_unlock_irqrestore(&mdev->req_lock, flags); 1765 } 1766 } 1767 1768 1769 /** 1770 * drbd_md_first_sector() - Returns the first sector number of the meta data area 1771 * @bdev: Meta data block device. 1772 * 1773 * BTW, for internal meta data, this happens to be the maximum capacity 1774 * we could agree upon with our peer node. 1775 */ 1776 static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev) 1777 { 1778 switch (bdev->dc.meta_dev_idx) { 1779 case DRBD_MD_INDEX_INTERNAL: 1780 case DRBD_MD_INDEX_FLEX_INT: 1781 return bdev->md.md_offset + bdev->md.bm_offset; 1782 case DRBD_MD_INDEX_FLEX_EXT: 1783 default: 1784 return bdev->md.md_offset; 1785 } 1786 } 1787 1788 /** 1789 * drbd_md_last_sector() - Return the last sector number of the meta data area 1790 * @bdev: Meta data block device. 1791 */ 1792 static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev) 1793 { 1794 switch (bdev->dc.meta_dev_idx) { 1795 case DRBD_MD_INDEX_INTERNAL: 1796 case DRBD_MD_INDEX_FLEX_INT: 1797 return bdev->md.md_offset + MD_AL_OFFSET - 1; 1798 case DRBD_MD_INDEX_FLEX_EXT: 1799 default: 1800 return bdev->md.md_offset + bdev->md.md_size_sect; 1801 } 1802 } 1803 1804 /* Returns the number of 512 byte sectors of the device */ 1805 static inline sector_t drbd_get_capacity(struct block_device *bdev) 1806 { 1807 /* return bdev ? get_capacity(bdev->bd_disk) : 0; */ 1808 return bdev ? bdev->bd_inode->i_size >> 9 : 0; 1809 } 1810 1811 /** 1812 * drbd_get_max_capacity() - Returns the capacity we announce to out peer 1813 * @bdev: Meta data block device. 1814 * 1815 * returns the capacity we announce to out peer. we clip ourselves at the 1816 * various MAX_SECTORS, because if we don't, current implementation will 1817 * oops sooner or later 1818 */ 1819 static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev) 1820 { 1821 sector_t s; 1822 switch (bdev->dc.meta_dev_idx) { 1823 case DRBD_MD_INDEX_INTERNAL: 1824 case DRBD_MD_INDEX_FLEX_INT: 1825 s = drbd_get_capacity(bdev->backing_bdev) 1826 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1827 drbd_md_first_sector(bdev)) 1828 : 0; 1829 break; 1830 case DRBD_MD_INDEX_FLEX_EXT: 1831 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1832 drbd_get_capacity(bdev->backing_bdev)); 1833 /* clip at maximum size the meta device can support */ 1834 s = min_t(sector_t, s, 1835 BM_EXT_TO_SECT(bdev->md.md_size_sect 1836 - bdev->md.bm_offset)); 1837 break; 1838 default: 1839 s = min_t(sector_t, DRBD_MAX_SECTORS, 1840 drbd_get_capacity(bdev->backing_bdev)); 1841 } 1842 return s; 1843 } 1844 1845 /** 1846 * drbd_md_ss__() - Return the sector number of our meta data super block 1847 * @mdev: DRBD device. 1848 * @bdev: Meta data block device. 1849 */ 1850 static inline sector_t drbd_md_ss__(struct drbd_conf *mdev, 1851 struct drbd_backing_dev *bdev) 1852 { 1853 switch (bdev->dc.meta_dev_idx) { 1854 default: /* external, some index */ 1855 return MD_RESERVED_SECT * bdev->dc.meta_dev_idx; 1856 case DRBD_MD_INDEX_INTERNAL: 1857 /* with drbd08, internal meta data is always "flexible" */ 1858 case DRBD_MD_INDEX_FLEX_INT: 1859 /* sizeof(struct md_on_disk_07) == 4k 1860 * position: last 4k aligned block of 4k size */ 1861 if (!bdev->backing_bdev) { 1862 if (__ratelimit(&drbd_ratelimit_state)) { 1863 dev_err(DEV, "bdev->backing_bdev==NULL\n"); 1864 dump_stack(); 1865 } 1866 return 0; 1867 } 1868 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL) 1869 - MD_AL_OFFSET; 1870 case DRBD_MD_INDEX_FLEX_EXT: 1871 return 0; 1872 } 1873 } 1874 1875 static inline void 1876 _drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 1877 { 1878 list_add_tail(&w->list, &q->q); 1879 up(&q->s); 1880 } 1881 1882 static inline void 1883 drbd_queue_work_front(struct drbd_work_queue *q, struct drbd_work *w) 1884 { 1885 unsigned long flags; 1886 spin_lock_irqsave(&q->q_lock, flags); 1887 list_add(&w->list, &q->q); 1888 up(&q->s); /* within the spinlock, 1889 see comment near end of drbd_worker() */ 1890 spin_unlock_irqrestore(&q->q_lock, flags); 1891 } 1892 1893 static inline void 1894 drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 1895 { 1896 unsigned long flags; 1897 spin_lock_irqsave(&q->q_lock, flags); 1898 list_add_tail(&w->list, &q->q); 1899 up(&q->s); /* within the spinlock, 1900 see comment near end of drbd_worker() */ 1901 spin_unlock_irqrestore(&q->q_lock, flags); 1902 } 1903 1904 static inline void wake_asender(struct drbd_conf *mdev) 1905 { 1906 if (test_bit(SIGNAL_ASENDER, &mdev->flags)) 1907 force_sig(DRBD_SIG, mdev->asender.task); 1908 } 1909 1910 static inline void request_ping(struct drbd_conf *mdev) 1911 { 1912 set_bit(SEND_PING, &mdev->flags); 1913 wake_asender(mdev); 1914 } 1915 1916 static inline int drbd_send_short_cmd(struct drbd_conf *mdev, 1917 enum drbd_packets cmd) 1918 { 1919 struct p_header h; 1920 return drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, &h, sizeof(h)); 1921 } 1922 1923 static inline int drbd_send_ping(struct drbd_conf *mdev) 1924 { 1925 struct p_header h; 1926 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING, &h, sizeof(h)); 1927 } 1928 1929 static inline int drbd_send_ping_ack(struct drbd_conf *mdev) 1930 { 1931 struct p_header h; 1932 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING_ACK, &h, sizeof(h)); 1933 } 1934 1935 static inline void drbd_thread_stop(struct drbd_thread *thi) 1936 { 1937 _drbd_thread_stop(thi, FALSE, TRUE); 1938 } 1939 1940 static inline void drbd_thread_stop_nowait(struct drbd_thread *thi) 1941 { 1942 _drbd_thread_stop(thi, FALSE, FALSE); 1943 } 1944 1945 static inline void drbd_thread_restart_nowait(struct drbd_thread *thi) 1946 { 1947 _drbd_thread_stop(thi, TRUE, FALSE); 1948 } 1949 1950 /* counts how many answer packets packets we expect from our peer, 1951 * for either explicit application requests, 1952 * or implicit barrier packets as necessary. 1953 * increased: 1954 * w_send_barrier 1955 * _req_mod(req, queue_for_net_write or queue_for_net_read); 1956 * it is much easier and equally valid to count what we queue for the 1957 * worker, even before it actually was queued or send. 1958 * (drbd_make_request_common; recovery path on read io-error) 1959 * decreased: 1960 * got_BarrierAck (respective tl_clear, tl_clear_barrier) 1961 * _req_mod(req, data_received) 1962 * [from receive_DataReply] 1963 * _req_mod(req, write_acked_by_peer or recv_acked_by_peer or neg_acked) 1964 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)] 1965 * for some reason it is NOT decreased in got_NegAck, 1966 * but in the resulting cleanup code from report_params. 1967 * we should try to remember the reason for that... 1968 * _req_mod(req, send_failed or send_canceled) 1969 * _req_mod(req, connection_lost_while_pending) 1970 * [from tl_clear_barrier] 1971 */ 1972 static inline void inc_ap_pending(struct drbd_conf *mdev) 1973 { 1974 atomic_inc(&mdev->ap_pending_cnt); 1975 } 1976 1977 #define ERR_IF_CNT_IS_NEGATIVE(which) \ 1978 if (atomic_read(&mdev->which) < 0) \ 1979 dev_err(DEV, "in %s:%d: " #which " = %d < 0 !\n", \ 1980 __func__ , __LINE__ , \ 1981 atomic_read(&mdev->which)) 1982 1983 #define dec_ap_pending(mdev) do { \ 1984 typecheck(struct drbd_conf *, mdev); \ 1985 if (atomic_dec_and_test(&mdev->ap_pending_cnt)) \ 1986 wake_up(&mdev->misc_wait); \ 1987 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt); } while (0) 1988 1989 /* counts how many resync-related answers we still expect from the peer 1990 * increase decrease 1991 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY) 1992 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK whith ID_SYNCER) 1993 * (or P_NEG_ACK with ID_SYNCER) 1994 */ 1995 static inline void inc_rs_pending(struct drbd_conf *mdev) 1996 { 1997 atomic_inc(&mdev->rs_pending_cnt); 1998 } 1999 2000 #define dec_rs_pending(mdev) do { \ 2001 typecheck(struct drbd_conf *, mdev); \ 2002 atomic_dec(&mdev->rs_pending_cnt); \ 2003 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt); } while (0) 2004 2005 /* counts how many answers we still need to send to the peer. 2006 * increased on 2007 * receive_Data unless protocol A; 2008 * we need to send a P_RECV_ACK (proto B) 2009 * or P_WRITE_ACK (proto C) 2010 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK 2011 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA 2012 * receive_Barrier_* we need to send a P_BARRIER_ACK 2013 */ 2014 static inline void inc_unacked(struct drbd_conf *mdev) 2015 { 2016 atomic_inc(&mdev->unacked_cnt); 2017 } 2018 2019 #define dec_unacked(mdev) do { \ 2020 typecheck(struct drbd_conf *, mdev); \ 2021 atomic_dec(&mdev->unacked_cnt); \ 2022 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 2023 2024 #define sub_unacked(mdev, n) do { \ 2025 typecheck(struct drbd_conf *, mdev); \ 2026 atomic_sub(n, &mdev->unacked_cnt); \ 2027 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 2028 2029 2030 static inline void put_net_conf(struct drbd_conf *mdev) 2031 { 2032 if (atomic_dec_and_test(&mdev->net_cnt)) 2033 wake_up(&mdev->misc_wait); 2034 } 2035 2036 /** 2037 * get_net_conf() - Increase ref count on mdev->net_conf; Returns 0 if nothing there 2038 * @mdev: DRBD device. 2039 * 2040 * You have to call put_net_conf() when finished working with mdev->net_conf. 2041 */ 2042 static inline int get_net_conf(struct drbd_conf *mdev) 2043 { 2044 int have_net_conf; 2045 2046 atomic_inc(&mdev->net_cnt); 2047 have_net_conf = mdev->state.conn >= C_UNCONNECTED; 2048 if (!have_net_conf) 2049 put_net_conf(mdev); 2050 return have_net_conf; 2051 } 2052 2053 /** 2054 * get_ldev() - Increase the ref count on mdev->ldev. Returns 0 if there is no ldev 2055 * @M: DRBD device. 2056 * 2057 * You have to call put_ldev() when finished working with mdev->ldev. 2058 */ 2059 #define get_ldev(M) __cond_lock(local, _get_ldev_if_state(M,D_INCONSISTENT)) 2060 #define get_ldev_if_state(M,MINS) __cond_lock(local, _get_ldev_if_state(M,MINS)) 2061 2062 static inline void put_ldev(struct drbd_conf *mdev) 2063 { 2064 __release(local); 2065 if (atomic_dec_and_test(&mdev->local_cnt)) 2066 wake_up(&mdev->misc_wait); 2067 D_ASSERT(atomic_read(&mdev->local_cnt) >= 0); 2068 } 2069 2070 #ifndef __CHECKER__ 2071 static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins) 2072 { 2073 int io_allowed; 2074 2075 atomic_inc(&mdev->local_cnt); 2076 io_allowed = (mdev->state.disk >= mins); 2077 if (!io_allowed) 2078 put_ldev(mdev); 2079 return io_allowed; 2080 } 2081 #else 2082 extern int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins); 2083 #endif 2084 2085 /* you must have an "get_ldev" reference */ 2086 static inline void drbd_get_syncer_progress(struct drbd_conf *mdev, 2087 unsigned long *bits_left, unsigned int *per_mil_done) 2088 { 2089 /* 2090 * this is to break it at compile time when we change that 2091 * (we may feel 4TB maximum storage per drbd is not enough) 2092 */ 2093 typecheck(unsigned long, mdev->rs_total); 2094 2095 /* note: both rs_total and rs_left are in bits, i.e. in 2096 * units of BM_BLOCK_SIZE. 2097 * for the percentage, we don't care. */ 2098 2099 *bits_left = drbd_bm_total_weight(mdev) - mdev->rs_failed; 2100 /* >> 10 to prevent overflow, 2101 * +1 to prevent division by zero */ 2102 if (*bits_left > mdev->rs_total) { 2103 /* doh. maybe a logic bug somewhere. 2104 * may also be just a race condition 2105 * between this and a disconnect during sync. 2106 * for now, just prevent in-kernel buffer overflow. 2107 */ 2108 smp_rmb(); 2109 dev_warn(DEV, "cs:%s rs_left=%lu > rs_total=%lu (rs_failed %lu)\n", 2110 drbd_conn_str(mdev->state.conn), 2111 *bits_left, mdev->rs_total, mdev->rs_failed); 2112 *per_mil_done = 0; 2113 } else { 2114 /* make sure the calculation happens in long context */ 2115 unsigned long tmp = 1000UL - 2116 (*bits_left >> 10)*1000UL 2117 / ((mdev->rs_total >> 10) + 1UL); 2118 *per_mil_done = tmp; 2119 } 2120 } 2121 2122 2123 /* this throttles on-the-fly application requests 2124 * according to max_buffers settings; 2125 * maybe re-implement using semaphores? */ 2126 static inline int drbd_get_max_buffers(struct drbd_conf *mdev) 2127 { 2128 int mxb = 1000000; /* arbitrary limit on open requests */ 2129 if (get_net_conf(mdev)) { 2130 mxb = mdev->net_conf->max_buffers; 2131 put_net_conf(mdev); 2132 } 2133 return mxb; 2134 } 2135 2136 static inline int drbd_state_is_stable(union drbd_state s) 2137 { 2138 2139 /* DO NOT add a default clause, we want the compiler to warn us 2140 * for any newly introduced state we may have forgotten to add here */ 2141 2142 switch ((enum drbd_conns)s.conn) { 2143 /* new io only accepted when there is no connection, ... */ 2144 case C_STANDALONE: 2145 case C_WF_CONNECTION: 2146 /* ... or there is a well established connection. */ 2147 case C_CONNECTED: 2148 case C_SYNC_SOURCE: 2149 case C_SYNC_TARGET: 2150 case C_VERIFY_S: 2151 case C_VERIFY_T: 2152 case C_PAUSED_SYNC_S: 2153 case C_PAUSED_SYNC_T: 2154 /* maybe stable, look at the disk state */ 2155 break; 2156 2157 /* no new io accepted during tansitional states 2158 * like handshake or teardown */ 2159 case C_DISCONNECTING: 2160 case C_UNCONNECTED: 2161 case C_TIMEOUT: 2162 case C_BROKEN_PIPE: 2163 case C_NETWORK_FAILURE: 2164 case C_PROTOCOL_ERROR: 2165 case C_TEAR_DOWN: 2166 case C_WF_REPORT_PARAMS: 2167 case C_STARTING_SYNC_S: 2168 case C_STARTING_SYNC_T: 2169 case C_WF_BITMAP_S: 2170 case C_WF_BITMAP_T: 2171 case C_WF_SYNC_UUID: 2172 case C_MASK: 2173 /* not "stable" */ 2174 return 0; 2175 } 2176 2177 switch ((enum drbd_disk_state)s.disk) { 2178 case D_DISKLESS: 2179 case D_INCONSISTENT: 2180 case D_OUTDATED: 2181 case D_CONSISTENT: 2182 case D_UP_TO_DATE: 2183 /* disk state is stable as well. */ 2184 break; 2185 2186 /* no new io accepted during tansitional states */ 2187 case D_ATTACHING: 2188 case D_FAILED: 2189 case D_NEGOTIATING: 2190 case D_UNKNOWN: 2191 case D_MASK: 2192 /* not "stable" */ 2193 return 0; 2194 } 2195 2196 return 1; 2197 } 2198 2199 static inline int __inc_ap_bio_cond(struct drbd_conf *mdev) 2200 { 2201 int mxb = drbd_get_max_buffers(mdev); 2202 2203 if (mdev->state.susp) 2204 return 0; 2205 if (test_bit(SUSPEND_IO, &mdev->flags)) 2206 return 0; 2207 2208 /* to avoid potential deadlock or bitmap corruption, 2209 * in various places, we only allow new application io 2210 * to start during "stable" states. */ 2211 2212 /* no new io accepted when attaching or detaching the disk */ 2213 if (!drbd_state_is_stable(mdev->state)) 2214 return 0; 2215 2216 /* since some older kernels don't have atomic_add_unless, 2217 * and we are within the spinlock anyways, we have this workaround. */ 2218 if (atomic_read(&mdev->ap_bio_cnt) > mxb) 2219 return 0; 2220 if (test_bit(BITMAP_IO, &mdev->flags)) 2221 return 0; 2222 if (atomic_read(&mdev->new_c_uuid)) 2223 return 0; 2224 return 1; 2225 } 2226 2227 /* I'd like to use wait_event_lock_irq, 2228 * but I'm not sure when it got introduced, 2229 * and not sure when it has 3 or 4 arguments */ 2230 static inline void inc_ap_bio(struct drbd_conf *mdev, int count) 2231 { 2232 /* compare with after_state_ch, 2233 * os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S */ 2234 DEFINE_WAIT(wait); 2235 2236 /* we wait here 2237 * as long as the device is suspended 2238 * until the bitmap is no longer on the fly during connection 2239 * handshake as long as we would exeed the max_buffer limit. 2240 * 2241 * to avoid races with the reconnect code, 2242 * we need to atomic_inc within the spinlock. */ 2243 2244 if (atomic_read(&mdev->new_c_uuid) && atomic_add_unless(&mdev->new_c_uuid, -1, 1)) 2245 drbd_queue_work_front(&mdev->data.work, &mdev->uuid_work); 2246 2247 spin_lock_irq(&mdev->req_lock); 2248 while (!__inc_ap_bio_cond(mdev)) { 2249 prepare_to_wait(&mdev->misc_wait, &wait, TASK_UNINTERRUPTIBLE); 2250 spin_unlock_irq(&mdev->req_lock); 2251 schedule(); 2252 finish_wait(&mdev->misc_wait, &wait); 2253 spin_lock_irq(&mdev->req_lock); 2254 } 2255 atomic_add(count, &mdev->ap_bio_cnt); 2256 spin_unlock_irq(&mdev->req_lock); 2257 } 2258 2259 static inline void dec_ap_bio(struct drbd_conf *mdev) 2260 { 2261 int mxb = drbd_get_max_buffers(mdev); 2262 int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt); 2263 2264 D_ASSERT(ap_bio >= 0); 2265 /* this currently does wake_up for every dec_ap_bio! 2266 * maybe rather introduce some type of hysteresis? 2267 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */ 2268 if (ap_bio < mxb) 2269 wake_up(&mdev->misc_wait); 2270 if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) { 2271 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags)) 2272 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w); 2273 } 2274 } 2275 2276 static inline void drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val) 2277 { 2278 mdev->ed_uuid = val; 2279 } 2280 2281 static inline int seq_cmp(u32 a, u32 b) 2282 { 2283 /* we assume wrap around at 32bit. 2284 * for wrap around at 24bit (old atomic_t), 2285 * we'd have to 2286 * a <<= 8; b <<= 8; 2287 */ 2288 return (s32)(a) - (s32)(b); 2289 } 2290 #define seq_lt(a, b) (seq_cmp((a), (b)) < 0) 2291 #define seq_gt(a, b) (seq_cmp((a), (b)) > 0) 2292 #define seq_ge(a, b) (seq_cmp((a), (b)) >= 0) 2293 #define seq_le(a, b) (seq_cmp((a), (b)) <= 0) 2294 /* CAUTION: please no side effects in arguments! */ 2295 #define seq_max(a, b) ((u32)(seq_gt((a), (b)) ? (a) : (b))) 2296 2297 static inline void update_peer_seq(struct drbd_conf *mdev, unsigned int new_seq) 2298 { 2299 unsigned int m; 2300 spin_lock(&mdev->peer_seq_lock); 2301 m = seq_max(mdev->peer_seq, new_seq); 2302 mdev->peer_seq = m; 2303 spin_unlock(&mdev->peer_seq_lock); 2304 if (m == new_seq) 2305 wake_up(&mdev->seq_wait); 2306 } 2307 2308 static inline void drbd_update_congested(struct drbd_conf *mdev) 2309 { 2310 struct sock *sk = mdev->data.socket->sk; 2311 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5) 2312 set_bit(NET_CONGESTED, &mdev->flags); 2313 } 2314 2315 static inline int drbd_queue_order_type(struct drbd_conf *mdev) 2316 { 2317 /* sorry, we currently have no working implementation 2318 * of distributed TCQ stuff */ 2319 #ifndef QUEUE_ORDERED_NONE 2320 #define QUEUE_ORDERED_NONE 0 2321 #endif 2322 return QUEUE_ORDERED_NONE; 2323 } 2324 2325 static inline void drbd_blk_run_queue(struct request_queue *q) 2326 { 2327 if (q && q->unplug_fn) 2328 q->unplug_fn(q); 2329 } 2330 2331 static inline void drbd_kick_lo(struct drbd_conf *mdev) 2332 { 2333 if (get_ldev(mdev)) { 2334 drbd_blk_run_queue(bdev_get_queue(mdev->ldev->backing_bdev)); 2335 put_ldev(mdev); 2336 } 2337 } 2338 2339 static inline void drbd_md_flush(struct drbd_conf *mdev) 2340 { 2341 int r; 2342 2343 if (test_bit(MD_NO_BARRIER, &mdev->flags)) 2344 return; 2345 2346 r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL, 2347 BLKDEV_IFL_WAIT); 2348 if (r) { 2349 set_bit(MD_NO_BARRIER, &mdev->flags); 2350 dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r); 2351 } 2352 } 2353 2354 #endif 2355