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/list.h> 32 #include <linux/sched.h> 33 #include <linux/bitops.h> 34 #include <linux/slab.h> 35 #include <linux/crypto.h> 36 #include <linux/ratelimit.h> 37 #include <linux/tcp.h> 38 #include <linux/mutex.h> 39 #include <linux/major.h> 40 #include <linux/blkdev.h> 41 #include <linux/genhd.h> 42 #include <net/tcp.h> 43 #include <linux/lru_cache.h> 44 #include <linux/prefetch.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 bool disable_sendpage; 63 extern bool 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 /* I don't remember why XCPU ... 76 * This is used to wake the asender, 77 * and to interrupt sending the sending task 78 * on disconnect. 79 */ 80 #define DRBD_SIG SIGXCPU 81 82 /* This is used to stop/restart our threads. 83 * Cannot use SIGTERM nor SIGKILL, since these 84 * are sent out by init on runlevel changes 85 * I choose SIGHUP for now. 86 */ 87 #define DRBD_SIGKILL SIGHUP 88 89 /* All EEs on the free list should have ID_VACANT (== 0) 90 * freshly allocated EEs get !ID_VACANT (== 1) 91 * so if it says "cannot dereference null pointer at address 0x00000001", 92 * it is most likely one of these :( */ 93 94 #define ID_IN_SYNC (4711ULL) 95 #define ID_OUT_OF_SYNC (4712ULL) 96 97 #define ID_SYNCER (-1ULL) 98 #define ID_VACANT 0 99 #define is_syncer_block_id(id) ((id) == ID_SYNCER) 100 #define UUID_NEW_BM_OFFSET ((u64)0x0001000000000000ULL) 101 102 struct drbd_conf; 103 104 105 /* to shorten dev_warn(DEV, "msg"); and relatives statements */ 106 #define DEV (disk_to_dev(mdev->vdisk)) 107 108 #define D_ASSERT(exp) if (!(exp)) \ 109 dev_err(DEV, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__) 110 111 #define ERR_IF(exp) if (({ \ 112 int _b = (exp) != 0; \ 113 if (_b) dev_err(DEV, "ASSERT FAILED: %s: (%s) in %s:%d\n", \ 114 __func__, #exp, __FILE__, __LINE__); \ 115 _b; \ 116 })) 117 118 /* Defines to control fault insertion */ 119 enum { 120 DRBD_FAULT_MD_WR = 0, /* meta data write */ 121 DRBD_FAULT_MD_RD = 1, /* read */ 122 DRBD_FAULT_RS_WR = 2, /* resync */ 123 DRBD_FAULT_RS_RD = 3, 124 DRBD_FAULT_DT_WR = 4, /* data */ 125 DRBD_FAULT_DT_RD = 5, 126 DRBD_FAULT_DT_RA = 6, /* data read ahead */ 127 DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */ 128 DRBD_FAULT_AL_EE = 8, /* alloc ee */ 129 DRBD_FAULT_RECEIVE = 9, /* Changes some bytes upon receiving a [rs]data block */ 130 131 DRBD_FAULT_MAX, 132 }; 133 134 extern unsigned int 135 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type); 136 137 static inline int 138 drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) { 139 #ifdef CONFIG_DRBD_FAULT_INJECTION 140 return fault_rate && 141 (enable_faults & (1<<type)) && 142 _drbd_insert_fault(mdev, type); 143 #else 144 return 0; 145 #endif 146 } 147 148 /* integer division, round _UP_ to the next integer */ 149 #define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0)) 150 /* usual integer division */ 151 #define div_floor(A, B) ((A)/(B)) 152 153 /* drbd_meta-data.c (still in drbd_main.c) */ 154 /* 4th incarnation of the disk layout. */ 155 #define DRBD_MD_MAGIC (DRBD_MAGIC+4) 156 157 extern struct drbd_conf **minor_table; 158 extern struct ratelimit_state drbd_ratelimit_state; 159 160 /* on the wire */ 161 enum drbd_packets { 162 /* receiver (data socket) */ 163 P_DATA = 0x00, 164 P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */ 165 P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */ 166 P_BARRIER = 0x03, 167 P_BITMAP = 0x04, 168 P_BECOME_SYNC_TARGET = 0x05, 169 P_BECOME_SYNC_SOURCE = 0x06, 170 P_UNPLUG_REMOTE = 0x07, /* Used at various times to hint the peer */ 171 P_DATA_REQUEST = 0x08, /* Used to ask for a data block */ 172 P_RS_DATA_REQUEST = 0x09, /* Used to ask for a data block for resync */ 173 P_SYNC_PARAM = 0x0a, 174 P_PROTOCOL = 0x0b, 175 P_UUIDS = 0x0c, 176 P_SIZES = 0x0d, 177 P_STATE = 0x0e, 178 P_SYNC_UUID = 0x0f, 179 P_AUTH_CHALLENGE = 0x10, 180 P_AUTH_RESPONSE = 0x11, 181 P_STATE_CHG_REQ = 0x12, 182 183 /* asender (meta socket */ 184 P_PING = 0x13, 185 P_PING_ACK = 0x14, 186 P_RECV_ACK = 0x15, /* Used in protocol B */ 187 P_WRITE_ACK = 0x16, /* Used in protocol C */ 188 P_RS_WRITE_ACK = 0x17, /* Is a P_WRITE_ACK, additionally call set_in_sync(). */ 189 P_DISCARD_ACK = 0x18, /* Used in proto C, two-primaries conflict detection */ 190 P_NEG_ACK = 0x19, /* Sent if local disk is unusable */ 191 P_NEG_DREPLY = 0x1a, /* Local disk is broken... */ 192 P_NEG_RS_DREPLY = 0x1b, /* Local disk is broken... */ 193 P_BARRIER_ACK = 0x1c, 194 P_STATE_CHG_REPLY = 0x1d, 195 196 /* "new" commands, no longer fitting into the ordering scheme above */ 197 198 P_OV_REQUEST = 0x1e, /* data socket */ 199 P_OV_REPLY = 0x1f, 200 P_OV_RESULT = 0x20, /* meta socket */ 201 P_CSUM_RS_REQUEST = 0x21, /* data socket */ 202 P_RS_IS_IN_SYNC = 0x22, /* meta socket */ 203 P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */ 204 P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */ 205 /* P_CKPT_FENCE_REQ = 0x25, * currently reserved for protocol D */ 206 /* P_CKPT_DISABLE_REQ = 0x26, * currently reserved for protocol D */ 207 P_DELAY_PROBE = 0x27, /* is used on BOTH sockets */ 208 P_OUT_OF_SYNC = 0x28, /* Mark as out of sync (Outrunning), data socket */ 209 P_RS_CANCEL = 0x29, /* meta: Used to cancel RS_DATA_REQUEST packet by SyncSource */ 210 211 P_MAX_CMD = 0x2A, 212 P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */ 213 P_MAX_OPT_CMD = 0x101, 214 215 /* special command ids for handshake */ 216 217 P_HAND_SHAKE_M = 0xfff1, /* First Packet on the MetaSock */ 218 P_HAND_SHAKE_S = 0xfff2, /* First Packet on the Socket */ 219 220 P_HAND_SHAKE = 0xfffe /* FIXED for the next century! */ 221 }; 222 223 static inline const char *cmdname(enum drbd_packets cmd) 224 { 225 /* THINK may need to become several global tables 226 * when we want to support more than 227 * one PRO_VERSION */ 228 static const char *cmdnames[] = { 229 [P_DATA] = "Data", 230 [P_DATA_REPLY] = "DataReply", 231 [P_RS_DATA_REPLY] = "RSDataReply", 232 [P_BARRIER] = "Barrier", 233 [P_BITMAP] = "ReportBitMap", 234 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget", 235 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource", 236 [P_UNPLUG_REMOTE] = "UnplugRemote", 237 [P_DATA_REQUEST] = "DataRequest", 238 [P_RS_DATA_REQUEST] = "RSDataRequest", 239 [P_SYNC_PARAM] = "SyncParam", 240 [P_SYNC_PARAM89] = "SyncParam89", 241 [P_PROTOCOL] = "ReportProtocol", 242 [P_UUIDS] = "ReportUUIDs", 243 [P_SIZES] = "ReportSizes", 244 [P_STATE] = "ReportState", 245 [P_SYNC_UUID] = "ReportSyncUUID", 246 [P_AUTH_CHALLENGE] = "AuthChallenge", 247 [P_AUTH_RESPONSE] = "AuthResponse", 248 [P_PING] = "Ping", 249 [P_PING_ACK] = "PingAck", 250 [P_RECV_ACK] = "RecvAck", 251 [P_WRITE_ACK] = "WriteAck", 252 [P_RS_WRITE_ACK] = "RSWriteAck", 253 [P_DISCARD_ACK] = "DiscardAck", 254 [P_NEG_ACK] = "NegAck", 255 [P_NEG_DREPLY] = "NegDReply", 256 [P_NEG_RS_DREPLY] = "NegRSDReply", 257 [P_BARRIER_ACK] = "BarrierAck", 258 [P_STATE_CHG_REQ] = "StateChgRequest", 259 [P_STATE_CHG_REPLY] = "StateChgReply", 260 [P_OV_REQUEST] = "OVRequest", 261 [P_OV_REPLY] = "OVReply", 262 [P_OV_RESULT] = "OVResult", 263 [P_CSUM_RS_REQUEST] = "CsumRSRequest", 264 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync", 265 [P_COMPRESSED_BITMAP] = "CBitmap", 266 [P_DELAY_PROBE] = "DelayProbe", 267 [P_OUT_OF_SYNC] = "OutOfSync", 268 [P_MAX_CMD] = NULL, 269 }; 270 271 if (cmd == P_HAND_SHAKE_M) 272 return "HandShakeM"; 273 if (cmd == P_HAND_SHAKE_S) 274 return "HandShakeS"; 275 if (cmd == P_HAND_SHAKE) 276 return "HandShake"; 277 if (cmd >= P_MAX_CMD) 278 return "Unknown"; 279 return cmdnames[cmd]; 280 } 281 282 /* for sending/receiving the bitmap, 283 * possibly in some encoding scheme */ 284 struct bm_xfer_ctx { 285 /* "const" 286 * stores total bits and long words 287 * of the bitmap, so we don't need to 288 * call the accessor functions over and again. */ 289 unsigned long bm_bits; 290 unsigned long bm_words; 291 /* during xfer, current position within the bitmap */ 292 unsigned long bit_offset; 293 unsigned long word_offset; 294 295 /* statistics; index: (h->command == P_BITMAP) */ 296 unsigned packets[2]; 297 unsigned bytes[2]; 298 }; 299 300 extern void INFO_bm_xfer_stats(struct drbd_conf *mdev, 301 const char *direction, struct bm_xfer_ctx *c); 302 303 static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c) 304 { 305 /* word_offset counts "native long words" (32 or 64 bit), 306 * aligned at 64 bit. 307 * Encoded packet may end at an unaligned bit offset. 308 * In case a fallback clear text packet is transmitted in 309 * between, we adjust this offset back to the last 64bit 310 * aligned "native long word", which makes coding and decoding 311 * the plain text bitmap much more convenient. */ 312 #if BITS_PER_LONG == 64 313 c->word_offset = c->bit_offset >> 6; 314 #elif BITS_PER_LONG == 32 315 c->word_offset = c->bit_offset >> 5; 316 c->word_offset &= ~(1UL); 317 #else 318 # error "unsupported BITS_PER_LONG" 319 #endif 320 } 321 322 #ifndef __packed 323 #define __packed __attribute__((packed)) 324 #endif 325 326 /* This is the layout for a packet on the wire. 327 * The byteorder is the network byte order. 328 * (except block_id and barrier fields. 329 * these are pointers to local structs 330 * and have no relevance for the partner, 331 * which just echoes them as received.) 332 * 333 * NOTE that the payload starts at a long aligned offset, 334 * regardless of 32 or 64 bit arch! 335 */ 336 struct p_header80 { 337 u32 magic; 338 u16 command; 339 u16 length; /* bytes of data after this header */ 340 u8 payload[0]; 341 } __packed; 342 343 /* Header for big packets, Used for data packets exceeding 64kB */ 344 struct p_header95 { 345 u16 magic; /* use DRBD_MAGIC_BIG here */ 346 u16 command; 347 u32 length; /* Use only 24 bits of that. Ignore the highest 8 bit. */ 348 u8 payload[0]; 349 } __packed; 350 351 union p_header { 352 struct p_header80 h80; 353 struct p_header95 h95; 354 }; 355 356 /* 357 * short commands, packets without payload, plain p_header: 358 * P_PING 359 * P_PING_ACK 360 * P_BECOME_SYNC_TARGET 361 * P_BECOME_SYNC_SOURCE 362 * P_UNPLUG_REMOTE 363 */ 364 365 /* 366 * commands with out-of-struct payload: 367 * P_BITMAP (no additional fields) 368 * P_DATA, P_DATA_REPLY (see p_data) 369 * P_COMPRESSED_BITMAP (see receive_compressed_bitmap) 370 */ 371 372 /* these defines must not be changed without changing the protocol version */ 373 #define DP_HARDBARRIER 1 /* depricated */ 374 #define DP_RW_SYNC 2 /* equals REQ_SYNC */ 375 #define DP_MAY_SET_IN_SYNC 4 376 #define DP_UNPLUG 8 /* not used anymore */ 377 #define DP_FUA 16 /* equals REQ_FUA */ 378 #define DP_FLUSH 32 /* equals REQ_FLUSH */ 379 #define DP_DISCARD 64 /* equals REQ_DISCARD */ 380 381 struct p_data { 382 union p_header head; 383 u64 sector; /* 64 bits sector number */ 384 u64 block_id; /* to identify the request in protocol B&C */ 385 u32 seq_num; 386 u32 dp_flags; 387 } __packed; 388 389 /* 390 * commands which share a struct: 391 * p_block_ack: 392 * P_RECV_ACK (proto B), P_WRITE_ACK (proto C), 393 * P_DISCARD_ACK (proto C, two-primaries conflict detection) 394 * p_block_req: 395 * P_DATA_REQUEST, P_RS_DATA_REQUEST 396 */ 397 struct p_block_ack { 398 struct p_header80 head; 399 u64 sector; 400 u64 block_id; 401 u32 blksize; 402 u32 seq_num; 403 } __packed; 404 405 406 struct p_block_req { 407 struct p_header80 head; 408 u64 sector; 409 u64 block_id; 410 u32 blksize; 411 u32 pad; /* to multiple of 8 Byte */ 412 } __packed; 413 414 /* 415 * commands with their own struct for additional fields: 416 * P_HAND_SHAKE 417 * P_BARRIER 418 * P_BARRIER_ACK 419 * P_SYNC_PARAM 420 * ReportParams 421 */ 422 423 struct p_handshake { 424 struct p_header80 head; /* 8 bytes */ 425 u32 protocol_min; 426 u32 feature_flags; 427 u32 protocol_max; 428 429 /* should be more than enough for future enhancements 430 * for now, feature_flags and the reserverd array shall be zero. 431 */ 432 433 u32 _pad; 434 u64 reserverd[7]; 435 } __packed; 436 /* 80 bytes, FIXED for the next century */ 437 438 struct p_barrier { 439 struct p_header80 head; 440 u32 barrier; /* barrier number _handle_ only */ 441 u32 pad; /* to multiple of 8 Byte */ 442 } __packed; 443 444 struct p_barrier_ack { 445 struct p_header80 head; 446 u32 barrier; 447 u32 set_size; 448 } __packed; 449 450 struct p_rs_param { 451 struct p_header80 head; 452 u32 rate; 453 454 /* Since protocol version 88 and higher. */ 455 char verify_alg[0]; 456 } __packed; 457 458 struct p_rs_param_89 { 459 struct p_header80 head; 460 u32 rate; 461 /* protocol version 89: */ 462 char verify_alg[SHARED_SECRET_MAX]; 463 char csums_alg[SHARED_SECRET_MAX]; 464 } __packed; 465 466 struct p_rs_param_95 { 467 struct p_header80 head; 468 u32 rate; 469 char verify_alg[SHARED_SECRET_MAX]; 470 char csums_alg[SHARED_SECRET_MAX]; 471 u32 c_plan_ahead; 472 u32 c_delay_target; 473 u32 c_fill_target; 474 u32 c_max_rate; 475 } __packed; 476 477 enum drbd_conn_flags { 478 CF_WANT_LOSE = 1, 479 CF_DRY_RUN = 2, 480 }; 481 482 struct p_protocol { 483 struct p_header80 head; 484 u32 protocol; 485 u32 after_sb_0p; 486 u32 after_sb_1p; 487 u32 after_sb_2p; 488 u32 conn_flags; 489 u32 two_primaries; 490 491 /* Since protocol version 87 and higher. */ 492 char integrity_alg[0]; 493 494 } __packed; 495 496 struct p_uuids { 497 struct p_header80 head; 498 u64 uuid[UI_EXTENDED_SIZE]; 499 } __packed; 500 501 struct p_rs_uuid { 502 struct p_header80 head; 503 u64 uuid; 504 } __packed; 505 506 struct p_sizes { 507 struct p_header80 head; 508 u64 d_size; /* size of disk */ 509 u64 u_size; /* user requested size */ 510 u64 c_size; /* current exported size */ 511 u32 max_bio_size; /* Maximal size of a BIO */ 512 u16 queue_order_type; /* not yet implemented in DRBD*/ 513 u16 dds_flags; /* use enum dds_flags here. */ 514 } __packed; 515 516 struct p_state { 517 struct p_header80 head; 518 u32 state; 519 } __packed; 520 521 struct p_req_state { 522 struct p_header80 head; 523 u32 mask; 524 u32 val; 525 } __packed; 526 527 struct p_req_state_reply { 528 struct p_header80 head; 529 u32 retcode; 530 } __packed; 531 532 struct p_drbd06_param { 533 u64 size; 534 u32 state; 535 u32 blksize; 536 u32 protocol; 537 u32 version; 538 u32 gen_cnt[5]; 539 u32 bit_map_gen[5]; 540 } __packed; 541 542 struct p_discard { 543 struct p_header80 head; 544 u64 block_id; 545 u32 seq_num; 546 u32 pad; 547 } __packed; 548 549 struct p_block_desc { 550 struct p_header80 head; 551 u64 sector; 552 u32 blksize; 553 u32 pad; /* to multiple of 8 Byte */ 554 } __packed; 555 556 /* Valid values for the encoding field. 557 * Bump proto version when changing this. */ 558 enum drbd_bitmap_code { 559 /* RLE_VLI_Bytes = 0, 560 * and other bit variants had been defined during 561 * algorithm evaluation. */ 562 RLE_VLI_Bits = 2, 563 }; 564 565 struct p_compressed_bm { 566 struct p_header80 head; 567 /* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code 568 * (encoding & 0x80): polarity (set/unset) of first runlength 569 * ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits 570 * used to pad up to head.length bytes 571 */ 572 u8 encoding; 573 574 u8 code[0]; 575 } __packed; 576 577 struct p_delay_probe93 { 578 struct p_header80 head; 579 u32 seq_num; /* sequence number to match the two probe packets */ 580 u32 offset; /* usecs the probe got sent after the reference time point */ 581 } __packed; 582 583 /* DCBP: Drbd Compressed Bitmap Packet ... */ 584 static inline enum drbd_bitmap_code 585 DCBP_get_code(struct p_compressed_bm *p) 586 { 587 return (enum drbd_bitmap_code)(p->encoding & 0x0f); 588 } 589 590 static inline void 591 DCBP_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code) 592 { 593 BUG_ON(code & ~0xf); 594 p->encoding = (p->encoding & ~0xf) | code; 595 } 596 597 static inline int 598 DCBP_get_start(struct p_compressed_bm *p) 599 { 600 return (p->encoding & 0x80) != 0; 601 } 602 603 static inline void 604 DCBP_set_start(struct p_compressed_bm *p, int set) 605 { 606 p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0); 607 } 608 609 static inline int 610 DCBP_get_pad_bits(struct p_compressed_bm *p) 611 { 612 return (p->encoding >> 4) & 0x7; 613 } 614 615 static inline void 616 DCBP_set_pad_bits(struct p_compressed_bm *p, int n) 617 { 618 BUG_ON(n & ~0x7); 619 p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4); 620 } 621 622 /* one bitmap packet, including the p_header, 623 * should fit within one _architecture independend_ page. 624 * so we need to use the fixed size 4KiB page size 625 * most architectures have used for a long time. 626 */ 627 #define BM_PACKET_PAYLOAD_BYTES (4096 - sizeof(struct p_header80)) 628 #define BM_PACKET_WORDS (BM_PACKET_PAYLOAD_BYTES/sizeof(long)) 629 #define BM_PACKET_VLI_BYTES_MAX (4096 - sizeof(struct p_compressed_bm)) 630 #if (PAGE_SIZE < 4096) 631 /* drbd_send_bitmap / receive_bitmap would break horribly */ 632 #error "PAGE_SIZE too small" 633 #endif 634 635 union p_polymorph { 636 union p_header header; 637 struct p_handshake handshake; 638 struct p_data data; 639 struct p_block_ack block_ack; 640 struct p_barrier barrier; 641 struct p_barrier_ack barrier_ack; 642 struct p_rs_param_89 rs_param_89; 643 struct p_rs_param_95 rs_param_95; 644 struct p_protocol protocol; 645 struct p_sizes sizes; 646 struct p_uuids uuids; 647 struct p_state state; 648 struct p_req_state req_state; 649 struct p_req_state_reply req_state_reply; 650 struct p_block_req block_req; 651 struct p_delay_probe93 delay_probe93; 652 struct p_rs_uuid rs_uuid; 653 struct p_block_desc block_desc; 654 } __packed; 655 656 /**********************************************************************/ 657 enum drbd_thread_state { 658 None, 659 Running, 660 Exiting, 661 Restarting 662 }; 663 664 struct drbd_thread { 665 spinlock_t t_lock; 666 struct task_struct *task; 667 struct completion stop; 668 enum drbd_thread_state t_state; 669 int (*function) (struct drbd_thread *); 670 struct drbd_conf *mdev; 671 int reset_cpu_mask; 672 }; 673 674 static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi) 675 { 676 /* THINK testing the t_state seems to be uncritical in all cases 677 * (but thread_{start,stop}), so we can read it *without* the lock. 678 * --lge */ 679 680 smp_rmb(); 681 return thi->t_state; 682 } 683 684 struct drbd_work; 685 typedef int (*drbd_work_cb)(struct drbd_conf *, struct drbd_work *, int cancel); 686 struct drbd_work { 687 struct list_head list; 688 drbd_work_cb cb; 689 }; 690 691 struct drbd_tl_epoch; 692 struct drbd_request { 693 struct drbd_work w; 694 struct drbd_conf *mdev; 695 696 /* if local IO is not allowed, will be NULL. 697 * if local IO _is_ allowed, holds the locally submitted bio clone, 698 * or, after local IO completion, the ERR_PTR(error). 699 * see drbd_endio_pri(). */ 700 struct bio *private_bio; 701 702 struct hlist_node collision; 703 sector_t sector; 704 unsigned int size; 705 unsigned int epoch; /* barrier_nr */ 706 707 /* barrier_nr: used to check on "completion" whether this req was in 708 * the current epoch, and we therefore have to close it, 709 * starting a new epoch... 710 */ 711 712 struct list_head tl_requests; /* ring list in the transfer log */ 713 struct bio *master_bio; /* master bio pointer */ 714 unsigned long rq_state; /* see comments above _req_mod() */ 715 unsigned long start_time; 716 }; 717 718 struct drbd_tl_epoch { 719 struct drbd_work w; 720 struct list_head requests; /* requests before */ 721 struct drbd_tl_epoch *next; /* pointer to the next barrier */ 722 unsigned int br_number; /* the barriers identifier. */ 723 int n_writes; /* number of requests attached before this barrier */ 724 }; 725 726 struct drbd_request; 727 728 /* These Tl_epoch_entries may be in one of 6 lists: 729 active_ee .. data packet being written 730 sync_ee .. syncer block being written 731 done_ee .. block written, need to send P_WRITE_ACK 732 read_ee .. [RS]P_DATA_REQUEST being read 733 */ 734 735 struct drbd_epoch { 736 struct list_head list; 737 unsigned int barrier_nr; 738 atomic_t epoch_size; /* increased on every request added. */ 739 atomic_t active; /* increased on every req. added, and dec on every finished. */ 740 unsigned long flags; 741 }; 742 743 /* drbd_epoch flag bits */ 744 enum { 745 DE_HAVE_BARRIER_NUMBER, 746 }; 747 748 enum epoch_event { 749 EV_PUT, 750 EV_GOT_BARRIER_NR, 751 EV_BECAME_LAST, 752 EV_CLEANUP = 32, /* used as flag */ 753 }; 754 755 struct drbd_wq_barrier { 756 struct drbd_work w; 757 struct completion done; 758 }; 759 760 struct digest_info { 761 int digest_size; 762 void *digest; 763 }; 764 765 struct drbd_epoch_entry { 766 struct drbd_work w; 767 struct hlist_node collision; 768 struct drbd_epoch *epoch; /* for writes */ 769 struct drbd_conf *mdev; 770 struct page *pages; 771 atomic_t pending_bios; 772 unsigned int size; 773 /* see comments on ee flag bits below */ 774 unsigned long flags; 775 sector_t sector; 776 union { 777 u64 block_id; 778 struct digest_info *digest; 779 }; 780 }; 781 782 /* ee flag bits. 783 * While corresponding bios are in flight, the only modification will be 784 * set_bit WAS_ERROR, which has to be atomic. 785 * If no bios are in flight yet, or all have been completed, 786 * non-atomic modification to ee->flags is ok. 787 */ 788 enum { 789 __EE_CALL_AL_COMPLETE_IO, 790 __EE_MAY_SET_IN_SYNC, 791 792 /* In case a barrier failed, 793 * we need to resubmit without the barrier flag. */ 794 __EE_RESUBMITTED, 795 796 /* we may have several bios per epoch entry. 797 * if any of those fail, we set this flag atomically 798 * from the endio callback */ 799 __EE_WAS_ERROR, 800 801 /* This ee has a pointer to a digest instead of a block id */ 802 __EE_HAS_DIGEST, 803 }; 804 #define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO) 805 #define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC) 806 #define EE_RESUBMITTED (1<<__EE_RESUBMITTED) 807 #define EE_WAS_ERROR (1<<__EE_WAS_ERROR) 808 #define EE_HAS_DIGEST (1<<__EE_HAS_DIGEST) 809 810 /* global flag bits */ 811 enum { 812 CREATE_BARRIER, /* next P_DATA is preceded by a P_BARRIER */ 813 SIGNAL_ASENDER, /* whether asender wants to be interrupted */ 814 SEND_PING, /* whether asender should send a ping asap */ 815 816 UNPLUG_QUEUED, /* only relevant with kernel 2.4 */ 817 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */ 818 MD_DIRTY, /* current uuids and flags not yet on disk */ 819 DISCARD_CONCURRENT, /* Set on one node, cleared on the peer! */ 820 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */ 821 CLUSTER_ST_CHANGE, /* Cluster wide state change going on... */ 822 CL_ST_CHG_SUCCESS, 823 CL_ST_CHG_FAIL, 824 CRASHED_PRIMARY, /* This node was a crashed primary. 825 * Gets cleared when the state.conn 826 * goes into C_CONNECTED state. */ 827 NO_BARRIER_SUPP, /* underlying block device doesn't implement barriers */ 828 CONSIDER_RESYNC, 829 830 MD_NO_FUA, /* Users wants us to not use FUA/FLUSH on meta data dev */ 831 SUSPEND_IO, /* suspend application io */ 832 BITMAP_IO, /* suspend application io; 833 once no more io in flight, start bitmap io */ 834 BITMAP_IO_QUEUED, /* Started bitmap IO */ 835 GO_DISKLESS, /* Disk is being detached, on io-error or admin request. */ 836 WAS_IO_ERROR, /* Local disk failed returned IO error */ 837 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */ 838 NET_CONGESTED, /* The data socket is congested */ 839 840 CONFIG_PENDING, /* serialization of (re)configuration requests. 841 * if set, also prevents the device from dying */ 842 DEVICE_DYING, /* device became unconfigured, 843 * but worker thread is still handling the cleanup. 844 * reconfiguring (nl_disk_conf, nl_net_conf) is dissalowed, 845 * while this is set. */ 846 RESIZE_PENDING, /* Size change detected locally, waiting for the response from 847 * the peer, if it changed there as well. */ 848 CONN_DRY_RUN, /* Expect disconnect after resync handshake. */ 849 GOT_PING_ACK, /* set when we receive a ping_ack packet, misc wait gets woken */ 850 NEW_CUR_UUID, /* Create new current UUID when thawing IO */ 851 AL_SUSPENDED, /* Activity logging is currently suspended. */ 852 AHEAD_TO_SYNC_SOURCE, /* Ahead -> SyncSource queued */ 853 STATE_SENT, /* Do not change state/UUIDs while this is set */ 854 }; 855 856 struct drbd_bitmap; /* opaque for drbd_conf */ 857 858 /* definition of bits in bm_flags to be used in drbd_bm_lock 859 * and drbd_bitmap_io and friends. */ 860 enum bm_flag { 861 /* do we need to kfree, or vfree bm_pages? */ 862 BM_P_VMALLOCED = 0x10000, /* internal use only, will be masked out */ 863 864 /* currently locked for bulk operation */ 865 BM_LOCKED_MASK = 0xf, 866 867 /* in detail, that is: */ 868 BM_DONT_CLEAR = 0x1, 869 BM_DONT_SET = 0x2, 870 BM_DONT_TEST = 0x4, 871 872 /* so we can mark it locked for bulk operation, 873 * and still allow all non-bulk operations */ 874 BM_IS_LOCKED = 0x8, 875 876 /* (test bit, count bit) allowed (common case) */ 877 BM_LOCKED_TEST_ALLOWED = BM_DONT_CLEAR | BM_DONT_SET | BM_IS_LOCKED, 878 879 /* testing bits, as well as setting new bits allowed, but clearing bits 880 * would be unexpected. Used during bitmap receive. Setting new bits 881 * requires sending of "out-of-sync" information, though. */ 882 BM_LOCKED_SET_ALLOWED = BM_DONT_CLEAR | BM_IS_LOCKED, 883 884 /* for drbd_bm_write_copy_pages, everything is allowed, 885 * only concurrent bulk operations are locked out. */ 886 BM_LOCKED_CHANGE_ALLOWED = BM_IS_LOCKED, 887 }; 888 889 struct drbd_work_queue { 890 struct list_head q; 891 struct semaphore s; /* producers up it, worker down()s it */ 892 spinlock_t q_lock; /* to protect the list. */ 893 }; 894 895 struct drbd_socket { 896 struct drbd_work_queue work; 897 struct mutex mutex; 898 struct socket *socket; 899 /* this way we get our 900 * send/receive buffers off the stack */ 901 union p_polymorph sbuf; 902 union p_polymorph rbuf; 903 }; 904 905 struct drbd_md { 906 u64 md_offset; /* sector offset to 'super' block */ 907 908 u64 la_size_sect; /* last agreed size, unit sectors */ 909 u64 uuid[UI_SIZE]; 910 u64 device_uuid; 911 u32 flags; 912 u32 md_size_sect; 913 914 s32 al_offset; /* signed relative sector offset to al area */ 915 s32 bm_offset; /* signed relative sector offset to bitmap */ 916 917 /* u32 al_nr_extents; important for restoring the AL 918 * is stored into sync_conf.al_extents, which in turn 919 * gets applied to act_log->nr_elements 920 */ 921 }; 922 923 /* for sync_conf and other types... */ 924 #define NL_PACKET(name, number, fields) struct name { fields }; 925 #define NL_INTEGER(pn,pr,member) int member; 926 #define NL_INT64(pn,pr,member) __u64 member; 927 #define NL_BIT(pn,pr,member) unsigned member:1; 928 #define NL_STRING(pn,pr,member,len) unsigned char member[len]; int member ## _len; 929 #include <linux/drbd_nl.h> 930 931 struct drbd_backing_dev { 932 struct block_device *backing_bdev; 933 struct block_device *md_bdev; 934 struct drbd_md md; 935 struct disk_conf dc; /* The user provided config... */ 936 sector_t known_size; /* last known size of that backing device */ 937 }; 938 939 struct drbd_md_io { 940 unsigned int done; 941 int error; 942 }; 943 944 struct bm_io_work { 945 struct drbd_work w; 946 char *why; 947 enum bm_flag flags; 948 int (*io_fn)(struct drbd_conf *mdev); 949 void (*done)(struct drbd_conf *mdev, int rv); 950 }; 951 952 enum write_ordering_e { 953 WO_none, 954 WO_drain_io, 955 WO_bdev_flush, 956 }; 957 958 struct fifo_buffer { 959 int *values; 960 unsigned int head_index; 961 unsigned int size; 962 }; 963 964 struct drbd_conf { 965 /* things that are stored as / read from meta data on disk */ 966 unsigned long flags; 967 968 /* configured by drbdsetup */ 969 struct net_conf *net_conf; /* protected by get_net_conf() and put_net_conf() */ 970 struct syncer_conf sync_conf; 971 struct drbd_backing_dev *ldev __protected_by(local); 972 973 sector_t p_size; /* partner's disk size */ 974 struct request_queue *rq_queue; 975 struct block_device *this_bdev; 976 struct gendisk *vdisk; 977 978 struct drbd_socket data; /* data/barrier/cstate/parameter packets */ 979 struct drbd_socket meta; /* ping/ack (metadata) packets */ 980 int agreed_pro_version; /* actually used protocol version */ 981 unsigned long last_received; /* in jiffies, either socket */ 982 unsigned int ko_count; 983 struct drbd_work resync_work, 984 unplug_work, 985 go_diskless, 986 md_sync_work, 987 start_resync_work; 988 struct timer_list resync_timer; 989 struct timer_list md_sync_timer; 990 struct timer_list start_resync_timer; 991 struct timer_list request_timer; 992 #ifdef DRBD_DEBUG_MD_SYNC 993 struct { 994 unsigned int line; 995 const char* func; 996 } last_md_mark_dirty; 997 #endif 998 999 /* Used after attach while negotiating new disk state. */ 1000 union drbd_state new_state_tmp; 1001 1002 union drbd_state state; 1003 wait_queue_head_t misc_wait; 1004 wait_queue_head_t state_wait; /* upon each state change. */ 1005 wait_queue_head_t net_cnt_wait; 1006 unsigned int send_cnt; 1007 unsigned int recv_cnt; 1008 unsigned int read_cnt; 1009 unsigned int writ_cnt; 1010 unsigned int al_writ_cnt; 1011 unsigned int bm_writ_cnt; 1012 atomic_t ap_bio_cnt; /* Requests we need to complete */ 1013 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */ 1014 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */ 1015 atomic_t unacked_cnt; /* Need to send replys for */ 1016 atomic_t local_cnt; /* Waiting for local completion */ 1017 atomic_t net_cnt; /* Users of net_conf */ 1018 spinlock_t req_lock; 1019 struct drbd_tl_epoch *unused_spare_tle; /* for pre-allocation */ 1020 struct drbd_tl_epoch *newest_tle; 1021 struct drbd_tl_epoch *oldest_tle; 1022 struct list_head out_of_sequence_requests; 1023 struct list_head barrier_acked_requests; 1024 struct hlist_head *tl_hash; 1025 unsigned int tl_hash_s; 1026 1027 /* blocks to resync in this run [unit BM_BLOCK_SIZE] */ 1028 unsigned long rs_total; 1029 /* number of resync blocks that failed in this run */ 1030 unsigned long rs_failed; 1031 /* Syncer's start time [unit jiffies] */ 1032 unsigned long rs_start; 1033 /* cumulated time in PausedSyncX state [unit jiffies] */ 1034 unsigned long rs_paused; 1035 /* skipped because csum was equal [unit BM_BLOCK_SIZE] */ 1036 unsigned long rs_same_csum; 1037 #define DRBD_SYNC_MARKS 8 1038 #define DRBD_SYNC_MARK_STEP (3*HZ) 1039 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */ 1040 unsigned long rs_mark_left[DRBD_SYNC_MARKS]; 1041 /* marks's time [unit jiffies] */ 1042 unsigned long rs_mark_time[DRBD_SYNC_MARKS]; 1043 /* current index into rs_mark_{left,time} */ 1044 int rs_last_mark; 1045 1046 /* where does the admin want us to start? (sector) */ 1047 sector_t ov_start_sector; 1048 /* where are we now? (sector) */ 1049 sector_t ov_position; 1050 /* Start sector of out of sync range (to merge printk reporting). */ 1051 sector_t ov_last_oos_start; 1052 /* size of out-of-sync range in sectors. */ 1053 sector_t ov_last_oos_size; 1054 unsigned long ov_left; /* in bits */ 1055 struct crypto_hash *csums_tfm; 1056 struct crypto_hash *verify_tfm; 1057 1058 unsigned long last_reattach_jif; 1059 unsigned long last_reconnect_jif; 1060 struct drbd_thread receiver; 1061 struct drbd_thread worker; 1062 struct drbd_thread asender; 1063 struct drbd_bitmap *bitmap; 1064 unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */ 1065 1066 /* Used to track operations of resync... */ 1067 struct lru_cache *resync; 1068 /* Number of locked elements in resync LRU */ 1069 unsigned int resync_locked; 1070 /* resync extent number waiting for application requests */ 1071 unsigned int resync_wenr; 1072 1073 int open_cnt; 1074 u64 *p_uuid; 1075 struct drbd_epoch *current_epoch; 1076 spinlock_t epoch_lock; 1077 unsigned int epochs; 1078 enum write_ordering_e write_ordering; 1079 struct list_head active_ee; /* IO in progress (P_DATA gets written to disk) */ 1080 struct list_head sync_ee; /* IO in progress (P_RS_DATA_REPLY gets written to disk) */ 1081 struct list_head done_ee; /* send ack */ 1082 struct list_head read_ee; /* IO in progress (any read) */ 1083 struct list_head net_ee; /* zero-copy network send in progress */ 1084 struct hlist_head *ee_hash; /* is proteced by req_lock! */ 1085 unsigned int ee_hash_s; 1086 1087 /* this one is protected by ee_lock, single thread */ 1088 struct drbd_epoch_entry *last_write_w_barrier; 1089 1090 int next_barrier_nr; 1091 struct hlist_head *app_reads_hash; /* is proteced by req_lock */ 1092 struct list_head resync_reads; 1093 atomic_t pp_in_use; /* allocated from page pool */ 1094 atomic_t pp_in_use_by_net; /* sendpage()d, still referenced by tcp */ 1095 wait_queue_head_t ee_wait; 1096 struct page *md_io_page; /* one page buffer for md_io */ 1097 struct page *md_io_tmpp; /* for logical_block_size != 512 */ 1098 struct drbd_md_io md_io; 1099 atomic_t md_io_in_use; /* protects the md_io, md_io_page and md_io_tmpp */ 1100 spinlock_t al_lock; 1101 wait_queue_head_t al_wait; 1102 struct lru_cache *act_log; /* activity log */ 1103 unsigned int al_tr_number; 1104 int al_tr_cycle; 1105 int al_tr_pos; /* position of the next transaction in the journal */ 1106 struct crypto_hash *cram_hmac_tfm; 1107 struct crypto_hash *integrity_w_tfm; /* to be used by the worker thread */ 1108 struct crypto_hash *integrity_r_tfm; /* to be used by the receiver thread */ 1109 void *int_dig_out; 1110 void *int_dig_in; 1111 void *int_dig_vv; 1112 wait_queue_head_t seq_wait; 1113 atomic_t packet_seq; 1114 unsigned int peer_seq; 1115 spinlock_t peer_seq_lock; 1116 unsigned int minor; 1117 unsigned long comm_bm_set; /* communicated number of set bits. */ 1118 cpumask_var_t cpu_mask; 1119 struct bm_io_work bm_io_work; 1120 u64 ed_uuid; /* UUID of the exposed data */ 1121 struct mutex state_mutex; 1122 char congestion_reason; /* Why we where congested... */ 1123 atomic_t rs_sect_in; /* for incoming resync data rate, SyncTarget */ 1124 atomic_t rs_sect_ev; /* for submitted resync data rate, both */ 1125 int rs_last_sect_ev; /* counter to compare with */ 1126 int rs_last_events; /* counter of read or write "events" (unit sectors) 1127 * on the lower level device when we last looked. */ 1128 int c_sync_rate; /* current resync rate after syncer throttle magic */ 1129 struct fifo_buffer rs_plan_s; /* correction values of resync planer */ 1130 int rs_in_flight; /* resync sectors in flight (to proxy, in proxy and from proxy) */ 1131 int rs_planed; /* resync sectors already planned */ 1132 atomic_t ap_in_flight; /* App sectors in flight (waiting for ack) */ 1133 int peer_max_bio_size; 1134 int local_max_bio_size; 1135 }; 1136 1137 static inline struct drbd_conf *minor_to_mdev(unsigned int minor) 1138 { 1139 struct drbd_conf *mdev; 1140 1141 mdev = minor < minor_count ? minor_table[minor] : NULL; 1142 1143 return mdev; 1144 } 1145 1146 static inline unsigned int mdev_to_minor(struct drbd_conf *mdev) 1147 { 1148 return mdev->minor; 1149 } 1150 1151 /* returns 1 if it was successful, 1152 * returns 0 if there was no data socket. 1153 * so wherever you are going to use the data.socket, e.g. do 1154 * if (!drbd_get_data_sock(mdev)) 1155 * return 0; 1156 * CODE(); 1157 * drbd_put_data_sock(mdev); 1158 */ 1159 static inline int drbd_get_data_sock(struct drbd_conf *mdev) 1160 { 1161 mutex_lock(&mdev->data.mutex); 1162 /* drbd_disconnect() could have called drbd_free_sock() 1163 * while we were waiting in down()... */ 1164 if (unlikely(mdev->data.socket == NULL)) { 1165 mutex_unlock(&mdev->data.mutex); 1166 return 0; 1167 } 1168 return 1; 1169 } 1170 1171 static inline void drbd_put_data_sock(struct drbd_conf *mdev) 1172 { 1173 mutex_unlock(&mdev->data.mutex); 1174 } 1175 1176 /* 1177 * function declarations 1178 *************************/ 1179 1180 /* drbd_main.c */ 1181 1182 enum chg_state_flags { 1183 CS_HARD = 1, 1184 CS_VERBOSE = 2, 1185 CS_WAIT_COMPLETE = 4, 1186 CS_SERIALIZE = 8, 1187 CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE, 1188 }; 1189 1190 enum dds_flags { 1191 DDSF_FORCED = 1, 1192 DDSF_NO_RESYNC = 2, /* Do not run a resync for the new space */ 1193 }; 1194 1195 extern void drbd_init_set_defaults(struct drbd_conf *mdev); 1196 extern enum drbd_state_rv drbd_change_state(struct drbd_conf *mdev, 1197 enum chg_state_flags f, 1198 union drbd_state mask, 1199 union drbd_state val); 1200 extern void drbd_force_state(struct drbd_conf *, union drbd_state, 1201 union drbd_state); 1202 extern enum drbd_state_rv _drbd_request_state(struct drbd_conf *, 1203 union drbd_state, 1204 union drbd_state, 1205 enum chg_state_flags); 1206 extern enum drbd_state_rv __drbd_set_state(struct drbd_conf *, union drbd_state, 1207 enum chg_state_flags, 1208 struct completion *done); 1209 extern void print_st_err(struct drbd_conf *, union drbd_state, 1210 union drbd_state, int); 1211 extern int drbd_thread_start(struct drbd_thread *thi); 1212 extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait); 1213 #ifdef CONFIG_SMP 1214 extern void drbd_thread_current_set_cpu(struct drbd_conf *mdev); 1215 extern void drbd_calc_cpu_mask(struct drbd_conf *mdev); 1216 #else 1217 #define drbd_thread_current_set_cpu(A) ({}) 1218 #define drbd_calc_cpu_mask(A) ({}) 1219 #endif 1220 extern void drbd_free_resources(struct drbd_conf *mdev); 1221 extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr, 1222 unsigned int set_size); 1223 extern void tl_clear(struct drbd_conf *mdev); 1224 extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *); 1225 extern void drbd_free_sock(struct drbd_conf *mdev); 1226 extern int drbd_send(struct drbd_conf *mdev, struct socket *sock, 1227 void *buf, size_t size, unsigned msg_flags); 1228 extern int drbd_send_protocol(struct drbd_conf *mdev); 1229 extern int drbd_send_uuids(struct drbd_conf *mdev); 1230 extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev); 1231 extern int drbd_gen_and_send_sync_uuid(struct drbd_conf *mdev); 1232 extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags); 1233 extern int drbd_send_state(struct drbd_conf *mdev, union drbd_state s); 1234 extern int drbd_send_current_state(struct drbd_conf *mdev); 1235 extern int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock, 1236 enum drbd_packets cmd, struct p_header80 *h, 1237 size_t size, unsigned msg_flags); 1238 #define USE_DATA_SOCKET 1 1239 #define USE_META_SOCKET 0 1240 extern int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket, 1241 enum drbd_packets cmd, struct p_header80 *h, 1242 size_t size); 1243 extern int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, 1244 char *data, size_t size); 1245 extern int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc); 1246 extern int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, 1247 u32 set_size); 1248 extern int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd, 1249 struct drbd_epoch_entry *e); 1250 extern int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd, 1251 struct p_block_req *rp); 1252 extern int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd, 1253 struct p_data *dp, int data_size); 1254 extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd, 1255 sector_t sector, int blksize, u64 block_id); 1256 extern int drbd_send_oos(struct drbd_conf *mdev, struct drbd_request *req); 1257 extern int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd, 1258 struct drbd_epoch_entry *e); 1259 extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req); 1260 extern int drbd_send_drequest(struct drbd_conf *mdev, int cmd, 1261 sector_t sector, int size, u64 block_id); 1262 extern int drbd_send_drequest_csum(struct drbd_conf *mdev, 1263 sector_t sector,int size, 1264 void *digest, int digest_size, 1265 enum drbd_packets cmd); 1266 extern int drbd_send_ov_request(struct drbd_conf *mdev,sector_t sector,int size); 1267 1268 extern int drbd_send_bitmap(struct drbd_conf *mdev); 1269 extern int _drbd_send_bitmap(struct drbd_conf *mdev); 1270 extern int drbd_send_sr_reply(struct drbd_conf *mdev, enum drbd_state_rv retcode); 1271 extern void drbd_free_bc(struct drbd_backing_dev *ldev); 1272 extern void drbd_mdev_cleanup(struct drbd_conf *mdev); 1273 void drbd_print_uuids(struct drbd_conf *mdev, const char *text); 1274 1275 extern void drbd_md_sync(struct drbd_conf *mdev); 1276 extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev); 1277 extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1278 extern void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1279 extern void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1280 extern void _drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1281 extern void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local); 1282 extern void drbd_md_set_flag(struct drbd_conf *mdev, int flags) __must_hold(local); 1283 extern void drbd_md_clear_flag(struct drbd_conf *mdev, int flags)__must_hold(local); 1284 extern int drbd_md_test_flag(struct drbd_backing_dev *, int); 1285 #ifndef DRBD_DEBUG_MD_SYNC 1286 extern void drbd_md_mark_dirty(struct drbd_conf *mdev); 1287 #else 1288 #define drbd_md_mark_dirty(m) drbd_md_mark_dirty_(m, __LINE__ , __func__ ) 1289 extern void drbd_md_mark_dirty_(struct drbd_conf *mdev, 1290 unsigned int line, const char *func); 1291 #endif 1292 extern void drbd_queue_bitmap_io(struct drbd_conf *mdev, 1293 int (*io_fn)(struct drbd_conf *), 1294 void (*done)(struct drbd_conf *, int), 1295 char *why, enum bm_flag flags); 1296 extern int drbd_bitmap_io(struct drbd_conf *mdev, 1297 int (*io_fn)(struct drbd_conf *), 1298 char *why, enum bm_flag flags); 1299 extern int drbd_bmio_set_n_write(struct drbd_conf *mdev); 1300 extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev); 1301 extern void drbd_go_diskless(struct drbd_conf *mdev); 1302 extern void drbd_ldev_destroy(struct drbd_conf *mdev); 1303 1304 1305 /* Meta data layout 1306 We reserve a 128MB Block (4k aligned) 1307 * either at the end of the backing device 1308 * or on a separate meta data device. */ 1309 1310 #define MD_RESERVED_SECT (128LU << 11) /* 128 MB, unit sectors */ 1311 /* The following numbers are sectors */ 1312 #define MD_AL_OFFSET 8 /* 8 Sectors after start of meta area */ 1313 #define MD_AL_MAX_SIZE 64 /* = 32 kb LOG ~ 3776 extents ~ 14 GB Storage */ 1314 /* Allows up to about 3.8TB */ 1315 #define MD_BM_OFFSET (MD_AL_OFFSET + MD_AL_MAX_SIZE) 1316 1317 /* Since the smalles IO unit is usually 512 byte */ 1318 #define MD_SECTOR_SHIFT 9 1319 #define MD_SECTOR_SIZE (1<<MD_SECTOR_SHIFT) 1320 1321 /* activity log */ 1322 #define AL_EXTENTS_PT ((MD_SECTOR_SIZE-12)/8-1) /* 61 ; Extents per 512B sector */ 1323 #define AL_EXTENT_SHIFT 22 /* One extent represents 4M Storage */ 1324 #define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT) 1325 1326 #if BITS_PER_LONG == 32 1327 #define LN2_BPL 5 1328 #define cpu_to_lel(A) cpu_to_le32(A) 1329 #define lel_to_cpu(A) le32_to_cpu(A) 1330 #elif BITS_PER_LONG == 64 1331 #define LN2_BPL 6 1332 #define cpu_to_lel(A) cpu_to_le64(A) 1333 #define lel_to_cpu(A) le64_to_cpu(A) 1334 #else 1335 #error "LN2 of BITS_PER_LONG unknown!" 1336 #endif 1337 1338 /* resync bitmap */ 1339 /* 16MB sized 'bitmap extent' to track syncer usage */ 1340 struct bm_extent { 1341 int rs_left; /* number of bits set (out of sync) in this extent. */ 1342 int rs_failed; /* number of failed resync requests in this extent. */ 1343 unsigned long flags; 1344 struct lc_element lce; 1345 }; 1346 1347 #define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */ 1348 #define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */ 1349 #define BME_PRIORITY 2 /* finish resync IO on this extent ASAP! App IO waiting! */ 1350 1351 /* drbd_bitmap.c */ 1352 /* 1353 * We need to store one bit for a block. 1354 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap. 1355 * Bit 0 ==> local node thinks this block is binary identical on both nodes 1356 * Bit 1 ==> local node thinks this block needs to be synced. 1357 */ 1358 1359 #define SLEEP_TIME (HZ/10) 1360 1361 #define BM_BLOCK_SHIFT 12 /* 4k per bit */ 1362 #define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT) 1363 /* (9+3) : 512 bytes @ 8 bits; representing 16M storage 1364 * per sector of on disk bitmap */ 1365 #define BM_EXT_SHIFT (BM_BLOCK_SHIFT + MD_SECTOR_SHIFT + 3) /* = 24 */ 1366 #define BM_EXT_SIZE (1<<BM_EXT_SHIFT) 1367 1368 #if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12) 1369 #error "HAVE YOU FIXED drbdmeta AS WELL??" 1370 #endif 1371 1372 /* thus many _storage_ sectors are described by one bit */ 1373 #define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9)) 1374 #define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9)) 1375 #define BM_SECT_PER_BIT BM_BIT_TO_SECT(1) 1376 1377 /* bit to represented kilo byte conversion */ 1378 #define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10)) 1379 1380 /* in which _bitmap_ extent (resp. sector) the bit for a certain 1381 * _storage_ sector is located in */ 1382 #define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9)) 1383 1384 /* how much _storage_ sectors we have per bitmap sector */ 1385 #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9)) 1386 #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1) 1387 1388 /* in one sector of the bitmap, we have this many activity_log extents. */ 1389 #define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT)) 1390 #define BM_WORDS_PER_AL_EXT (1 << (AL_EXTENT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL)) 1391 1392 #define BM_BLOCKS_PER_BM_EXT_B (BM_EXT_SHIFT - BM_BLOCK_SHIFT) 1393 #define BM_BLOCKS_PER_BM_EXT_MASK ((1<<BM_BLOCKS_PER_BM_EXT_B) - 1) 1394 1395 /* the extent in "PER_EXTENT" below is an activity log extent 1396 * we need that many (long words/bytes) to store the bitmap 1397 * of one AL_EXTENT_SIZE chunk of storage. 1398 * we can store the bitmap for that many AL_EXTENTS within 1399 * one sector of the _on_disk_ bitmap: 1400 * bit 0 bit 37 bit 38 bit (512*8)-1 1401 * ...|........|........|.. // ..|........| 1402 * sect. 0 `296 `304 ^(512*8*8)-1 1403 * 1404 #define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG ) 1405 #define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128 1406 #define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4 1407 */ 1408 1409 #define DRBD_MAX_SECTORS_32 (0xffffffffLU) 1410 #define DRBD_MAX_SECTORS_BM \ 1411 ((MD_RESERVED_SECT - MD_BM_OFFSET) * (1LL<<(BM_EXT_SHIFT-9))) 1412 #if DRBD_MAX_SECTORS_BM < DRBD_MAX_SECTORS_32 1413 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1414 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_BM 1415 #elif !defined(CONFIG_LBDAF) && BITS_PER_LONG == 32 1416 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_32 1417 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_32 1418 #else 1419 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1420 /* 16 TB in units of sectors */ 1421 #if BITS_PER_LONG == 32 1422 /* adjust by one page worth of bitmap, 1423 * so we won't wrap around in drbd_bm_find_next_bit. 1424 * you should use 64bit OS for that much storage, anyways. */ 1425 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff) 1426 #else 1427 /* we allow up to 1 PiB now on 64bit architecture with "flexible" meta data */ 1428 #define DRBD_MAX_SECTORS_FLEX (1UL << 51) 1429 /* corresponds to (1UL << 38) bits right now. */ 1430 #endif 1431 #endif 1432 1433 /* Sector shift value for the "hash" functions of tl_hash and ee_hash tables. 1434 * With a value of 8 all IO in one 128K block make it to the same slot of the 1435 * hash table. */ 1436 #define HT_SHIFT 8 1437 #define DRBD_MAX_BIO_SIZE (1U<<(9+HT_SHIFT)) 1438 #define DRBD_MAX_BIO_SIZE_SAFE (1 << 12) /* Works always = 4k */ 1439 1440 #define DRBD_MAX_SIZE_H80_PACKET (1 << 15) /* The old header only allows packets up to 32Kib data */ 1441 1442 /* Number of elements in the app_reads_hash */ 1443 #define APP_R_HSIZE 15 1444 1445 extern int drbd_bm_init(struct drbd_conf *mdev); 1446 extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors, int set_new_bits); 1447 extern void drbd_bm_cleanup(struct drbd_conf *mdev); 1448 extern void drbd_bm_set_all(struct drbd_conf *mdev); 1449 extern void drbd_bm_clear_all(struct drbd_conf *mdev); 1450 /* set/clear/test only a few bits at a time */ 1451 extern int drbd_bm_set_bits( 1452 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1453 extern int drbd_bm_clear_bits( 1454 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1455 extern int drbd_bm_count_bits( 1456 struct drbd_conf *mdev, const unsigned long s, const unsigned long e); 1457 /* bm_set_bits variant for use while holding drbd_bm_lock, 1458 * may process the whole bitmap in one go */ 1459 extern void _drbd_bm_set_bits(struct drbd_conf *mdev, 1460 const unsigned long s, const unsigned long e); 1461 extern int drbd_bm_test_bit(struct drbd_conf *mdev, unsigned long bitnr); 1462 extern int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr); 1463 extern int drbd_bm_write_page(struct drbd_conf *mdev, unsigned int idx) __must_hold(local); 1464 extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local); 1465 extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local); 1466 extern int drbd_bm_write_copy_pages(struct drbd_conf *mdev) __must_hold(local); 1467 extern unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev, 1468 unsigned long al_enr); 1469 extern size_t drbd_bm_words(struct drbd_conf *mdev); 1470 extern unsigned long drbd_bm_bits(struct drbd_conf *mdev); 1471 extern sector_t drbd_bm_capacity(struct drbd_conf *mdev); 1472 1473 #define DRBD_END_OF_BITMAP (~(unsigned long)0) 1474 extern unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1475 /* bm_find_next variants for use while you hold drbd_bm_lock() */ 1476 extern unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1477 extern unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo); 1478 extern unsigned long _drbd_bm_total_weight(struct drbd_conf *mdev); 1479 extern unsigned long drbd_bm_total_weight(struct drbd_conf *mdev); 1480 extern int drbd_bm_rs_done(struct drbd_conf *mdev); 1481 /* for receive_bitmap */ 1482 extern void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset, 1483 size_t number, unsigned long *buffer); 1484 /* for _drbd_send_bitmap */ 1485 extern void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset, 1486 size_t number, unsigned long *buffer); 1487 1488 extern void drbd_bm_lock(struct drbd_conf *mdev, char *why, enum bm_flag flags); 1489 extern void drbd_bm_unlock(struct drbd_conf *mdev); 1490 /* drbd_main.c */ 1491 1492 extern struct kmem_cache *drbd_request_cache; 1493 extern struct kmem_cache *drbd_ee_cache; /* epoch entries */ 1494 extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 1495 extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 1496 extern mempool_t *drbd_request_mempool; 1497 extern mempool_t *drbd_ee_mempool; 1498 1499 /* drbd's page pool, used to buffer data received from the peer, 1500 * or data requested by the peer. 1501 * 1502 * This does not have an emergency reserve. 1503 * 1504 * When allocating from this pool, it first takes pages from the pool. 1505 * Only if the pool is depleted will try to allocate from the system. 1506 * 1507 * The assumption is that pages taken from this pool will be processed, 1508 * and given back, "quickly", and then can be recycled, so we can avoid 1509 * frequent calls to alloc_page(), and still will be able to make progress even 1510 * under memory pressure. 1511 */ 1512 extern struct page *drbd_pp_pool; 1513 extern spinlock_t drbd_pp_lock; 1514 extern int drbd_pp_vacant; 1515 extern wait_queue_head_t drbd_pp_wait; 1516 1517 /* We also need a standard (emergency-reserve backed) page pool 1518 * for meta data IO (activity log, bitmap). 1519 * We can keep it global, as long as it is used as "N pages at a time". 1520 * 128 should be plenty, currently we probably can get away with as few as 1. 1521 */ 1522 #define DRBD_MIN_POOL_PAGES 128 1523 extern mempool_t *drbd_md_io_page_pool; 1524 1525 /* We also need to make sure we get a bio 1526 * when we need it for housekeeping purposes */ 1527 extern struct bio_set *drbd_md_io_bio_set; 1528 /* to allocate from that set */ 1529 extern struct bio *bio_alloc_drbd(gfp_t gfp_mask); 1530 1531 extern rwlock_t global_state_lock; 1532 1533 extern struct drbd_conf *drbd_new_device(unsigned int minor); 1534 extern void drbd_free_mdev(struct drbd_conf *mdev); 1535 1536 extern int proc_details; 1537 1538 /* drbd_req */ 1539 extern void drbd_make_request(struct request_queue *q, struct bio *bio); 1540 extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req); 1541 extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec); 1542 extern int is_valid_ar_handle(struct drbd_request *, sector_t); 1543 1544 1545 /* drbd_nl.c */ 1546 extern void drbd_suspend_io(struct drbd_conf *mdev); 1547 extern void drbd_resume_io(struct drbd_conf *mdev); 1548 extern char *ppsize(char *buf, unsigned long long size); 1549 extern sector_t drbd_new_dev_size(struct drbd_conf *, struct drbd_backing_dev *, int); 1550 enum determine_dev_size { dev_size_error = -1, unchanged = 0, shrunk = 1, grew = 2 }; 1551 extern enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *, enum dds_flags) __must_hold(local); 1552 extern void resync_after_online_grow(struct drbd_conf *); 1553 extern void drbd_reconsider_max_bio_size(struct drbd_conf *mdev); 1554 extern enum drbd_state_rv drbd_set_role(struct drbd_conf *mdev, 1555 enum drbd_role new_role, 1556 int force); 1557 extern enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev); 1558 extern void drbd_try_outdate_peer_async(struct drbd_conf *mdev); 1559 extern int drbd_khelper(struct drbd_conf *mdev, char *cmd); 1560 1561 /* drbd_worker.c */ 1562 extern int drbd_worker(struct drbd_thread *thi); 1563 extern int drbd_alter_sa(struct drbd_conf *mdev, int na); 1564 extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side); 1565 extern void resume_next_sg(struct drbd_conf *mdev); 1566 extern void suspend_other_sg(struct drbd_conf *mdev); 1567 extern int drbd_resync_finished(struct drbd_conf *mdev); 1568 /* maybe rather drbd_main.c ? */ 1569 extern void *drbd_md_get_buffer(struct drbd_conf *mdev); 1570 extern void drbd_md_put_buffer(struct drbd_conf *mdev); 1571 extern int drbd_md_sync_page_io(struct drbd_conf *mdev, 1572 struct drbd_backing_dev *bdev, sector_t sector, int rw); 1573 extern void wait_until_done_or_disk_failure(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, 1574 unsigned int *done); 1575 extern void drbd_ov_oos_found(struct drbd_conf*, sector_t, int); 1576 extern void drbd_rs_controller_reset(struct drbd_conf *mdev); 1577 1578 static inline void ov_oos_print(struct drbd_conf *mdev) 1579 { 1580 if (mdev->ov_last_oos_size) { 1581 dev_err(DEV, "Out of sync: start=%llu, size=%lu (sectors)\n", 1582 (unsigned long long)mdev->ov_last_oos_start, 1583 (unsigned long)mdev->ov_last_oos_size); 1584 } 1585 mdev->ov_last_oos_size=0; 1586 } 1587 1588 1589 extern void drbd_csum_bio(struct drbd_conf *, struct crypto_hash *, struct bio *, void *); 1590 extern void drbd_csum_ee(struct drbd_conf *, struct crypto_hash *, struct drbd_epoch_entry *, void *); 1591 /* worker callbacks */ 1592 extern int w_req_cancel_conflict(struct drbd_conf *, struct drbd_work *, int); 1593 extern int w_read_retry_remote(struct drbd_conf *, struct drbd_work *, int); 1594 extern int w_e_end_data_req(struct drbd_conf *, struct drbd_work *, int); 1595 extern int w_e_end_rsdata_req(struct drbd_conf *, struct drbd_work *, int); 1596 extern int w_e_end_csum_rs_req(struct drbd_conf *, struct drbd_work *, int); 1597 extern int w_e_end_ov_reply(struct drbd_conf *, struct drbd_work *, int); 1598 extern int w_e_end_ov_req(struct drbd_conf *, struct drbd_work *, int); 1599 extern int w_ov_finished(struct drbd_conf *, struct drbd_work *, int); 1600 extern int w_resync_timer(struct drbd_conf *, struct drbd_work *, int); 1601 extern int w_resume_next_sg(struct drbd_conf *, struct drbd_work *, int); 1602 extern int w_send_write_hint(struct drbd_conf *, struct drbd_work *, int); 1603 extern int w_send_dblock(struct drbd_conf *, struct drbd_work *, int); 1604 extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int); 1605 extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int); 1606 extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int); 1607 extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int); 1608 extern int w_restart_disk_io(struct drbd_conf *, struct drbd_work *, int); 1609 extern int w_send_oos(struct drbd_conf *, struct drbd_work *, int); 1610 extern int w_start_resync(struct drbd_conf *, struct drbd_work *, int); 1611 1612 extern void resync_timer_fn(unsigned long data); 1613 extern void start_resync_timer_fn(unsigned long data); 1614 1615 /* drbd_receiver.c */ 1616 extern int drbd_rs_should_slow_down(struct drbd_conf *mdev, sector_t sector); 1617 extern int drbd_submit_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, 1618 const unsigned rw, const int fault_type); 1619 extern int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list); 1620 extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev, 1621 u64 id, 1622 sector_t sector, 1623 unsigned int data_size, 1624 gfp_t gfp_mask) __must_hold(local); 1625 extern void drbd_free_some_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, 1626 int is_net); 1627 #define drbd_free_ee(m,e) drbd_free_some_ee(m, e, 0) 1628 #define drbd_free_net_ee(m,e) drbd_free_some_ee(m, e, 1) 1629 extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1630 struct list_head *head); 1631 extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1632 struct list_head *head); 1633 extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled); 1634 extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed); 1635 extern void drbd_flush_workqueue(struct drbd_conf *mdev); 1636 extern void drbd_free_tl_hash(struct drbd_conf *mdev); 1637 1638 /* yes, there is kernel_setsockopt, but only since 2.6.18. we don't need to 1639 * mess with get_fs/set_fs, we know we are KERNEL_DS always. */ 1640 static inline int drbd_setsockopt(struct socket *sock, int level, int optname, 1641 char __user *optval, int optlen) 1642 { 1643 int err; 1644 if (level == SOL_SOCKET) 1645 err = sock_setsockopt(sock, level, optname, optval, optlen); 1646 else 1647 err = sock->ops->setsockopt(sock, level, optname, optval, 1648 optlen); 1649 return err; 1650 } 1651 1652 static inline void drbd_tcp_cork(struct socket *sock) 1653 { 1654 int __user val = 1; 1655 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1656 (char __user *)&val, sizeof(val)); 1657 } 1658 1659 static inline void drbd_tcp_uncork(struct socket *sock) 1660 { 1661 int __user val = 0; 1662 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1663 (char __user *)&val, sizeof(val)); 1664 } 1665 1666 static inline void drbd_tcp_nodelay(struct socket *sock) 1667 { 1668 int __user val = 1; 1669 (void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY, 1670 (char __user *)&val, sizeof(val)); 1671 } 1672 1673 static inline void drbd_tcp_quickack(struct socket *sock) 1674 { 1675 int __user val = 2; 1676 (void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK, 1677 (char __user *)&val, sizeof(val)); 1678 } 1679 1680 void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo); 1681 1682 /* drbd_proc.c */ 1683 extern struct proc_dir_entry *drbd_proc; 1684 extern const struct file_operations drbd_proc_fops; 1685 extern const char *drbd_conn_str(enum drbd_conns s); 1686 extern const char *drbd_role_str(enum drbd_role s); 1687 1688 /* drbd_actlog.c */ 1689 extern void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector); 1690 extern void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector); 1691 extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector); 1692 extern int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1693 extern int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1694 extern void drbd_rs_cancel_all(struct drbd_conf *mdev); 1695 extern int drbd_rs_del_all(struct drbd_conf *mdev); 1696 extern void drbd_rs_failed_io(struct drbd_conf *mdev, 1697 sector_t sector, int size); 1698 extern int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *); 1699 extern void drbd_advance_rs_marks(struct drbd_conf *mdev, unsigned long still_to_go); 1700 extern void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector, 1701 int size, const char *file, const unsigned int line); 1702 #define drbd_set_in_sync(mdev, sector, size) \ 1703 __drbd_set_in_sync(mdev, sector, size, __FILE__, __LINE__) 1704 extern int __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector, 1705 int size, const char *file, const unsigned int line); 1706 #define drbd_set_out_of_sync(mdev, sector, size) \ 1707 __drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__) 1708 extern void drbd_al_apply_to_bm(struct drbd_conf *mdev); 1709 extern void drbd_al_shrink(struct drbd_conf *mdev); 1710 1711 1712 /* drbd_nl.c */ 1713 1714 void drbd_nl_cleanup(void); 1715 int __init drbd_nl_init(void); 1716 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state); 1717 void drbd_bcast_sync_progress(struct drbd_conf *mdev); 1718 void drbd_bcast_ee(struct drbd_conf *mdev, 1719 const char *reason, const int dgs, 1720 const char* seen_hash, const char* calc_hash, 1721 const struct drbd_epoch_entry* e); 1722 1723 1724 /** 1725 * DOC: DRBD State macros 1726 * 1727 * These macros are used to express state changes in easily readable form. 1728 * 1729 * The NS macros expand to a mask and a value, that can be bit ored onto the 1730 * current state as soon as the spinlock (req_lock) was taken. 1731 * 1732 * The _NS macros are used for state functions that get called with the 1733 * spinlock. These macros expand directly to the new state value. 1734 * 1735 * Besides the basic forms NS() and _NS() additional _?NS[23] are defined 1736 * to express state changes that affect more than one aspect of the state. 1737 * 1738 * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY) 1739 * Means that the network connection was established and that the peer 1740 * is in secondary role. 1741 */ 1742 #define role_MASK R_MASK 1743 #define peer_MASK R_MASK 1744 #define disk_MASK D_MASK 1745 #define pdsk_MASK D_MASK 1746 #define conn_MASK C_MASK 1747 #define susp_MASK 1 1748 #define user_isp_MASK 1 1749 #define aftr_isp_MASK 1 1750 #define susp_nod_MASK 1 1751 #define susp_fen_MASK 1 1752 1753 #define NS(T, S) \ 1754 ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \ 1755 ({ union drbd_state val; val.i = 0; val.T = (S); val; }) 1756 #define NS2(T1, S1, T2, S2) \ 1757 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1758 mask.T2 = T2##_MASK; mask; }), \ 1759 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1760 val.T2 = (S2); val; }) 1761 #define NS3(T1, S1, T2, S2, T3, S3) \ 1762 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1763 mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \ 1764 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1765 val.T2 = (S2); val.T3 = (S3); val; }) 1766 1767 #define _NS(D, T, S) \ 1768 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; }) 1769 #define _NS2(D, T1, S1, T2, S2) \ 1770 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1771 __ns.T2 = (S2); __ns; }) 1772 #define _NS3(D, T1, S1, T2, S2, T3, S3) \ 1773 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1774 __ns.T2 = (S2); __ns.T3 = (S3); __ns; }) 1775 1776 /* 1777 * inline helper functions 1778 *************************/ 1779 1780 /* see also page_chain_add and friends in drbd_receiver.c */ 1781 static inline struct page *page_chain_next(struct page *page) 1782 { 1783 return (struct page *)page_private(page); 1784 } 1785 #define page_chain_for_each(page) \ 1786 for (; page && ({ prefetch(page_chain_next(page)); 1; }); \ 1787 page = page_chain_next(page)) 1788 #define page_chain_for_each_safe(page, n) \ 1789 for (; page && ({ n = page_chain_next(page); 1; }); page = n) 1790 1791 static inline int drbd_ee_has_active_page(struct drbd_epoch_entry *e) 1792 { 1793 struct page *page = e->pages; 1794 page_chain_for_each(page) { 1795 if (page_count(page) > 1) 1796 return 1; 1797 } 1798 return 0; 1799 } 1800 1801 static inline void drbd_state_lock(struct drbd_conf *mdev) 1802 { 1803 wait_event(mdev->misc_wait, 1804 !test_and_set_bit(CLUSTER_ST_CHANGE, &mdev->flags)); 1805 } 1806 1807 static inline void drbd_state_unlock(struct drbd_conf *mdev) 1808 { 1809 clear_bit(CLUSTER_ST_CHANGE, &mdev->flags); 1810 wake_up(&mdev->misc_wait); 1811 } 1812 1813 static inline enum drbd_state_rv 1814 _drbd_set_state(struct drbd_conf *mdev, union drbd_state ns, 1815 enum chg_state_flags flags, struct completion *done) 1816 { 1817 enum drbd_state_rv rv; 1818 1819 read_lock(&global_state_lock); 1820 rv = __drbd_set_state(mdev, ns, flags, done); 1821 read_unlock(&global_state_lock); 1822 1823 return rv; 1824 } 1825 1826 /** 1827 * drbd_request_state() - Reqest a state change 1828 * @mdev: DRBD device. 1829 * @mask: mask of state bits to change. 1830 * @val: value of new state bits. 1831 * 1832 * This is the most graceful way of requesting a state change. It is verbose 1833 * quite verbose in case the state change is not possible, and all those 1834 * state changes are globally serialized. 1835 */ 1836 static inline int drbd_request_state(struct drbd_conf *mdev, 1837 union drbd_state mask, 1838 union drbd_state val) 1839 { 1840 return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED); 1841 } 1842 1843 #define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__) 1844 static inline void __drbd_chk_io_error_(struct drbd_conf *mdev, int forcedetach, const char *where) 1845 { 1846 switch (mdev->ldev->dc.on_io_error) { 1847 case EP_PASS_ON: 1848 if (!forcedetach) { 1849 if (__ratelimit(&drbd_ratelimit_state)) 1850 dev_err(DEV, "Local IO failed in %s.\n", where); 1851 if (mdev->state.disk > D_INCONSISTENT) 1852 _drbd_set_state(_NS(mdev, disk, D_INCONSISTENT), CS_HARD, NULL); 1853 break; 1854 } 1855 /* NOTE fall through to detach case if forcedetach set */ 1856 case EP_DETACH: 1857 case EP_CALL_HELPER: 1858 set_bit(WAS_IO_ERROR, &mdev->flags); 1859 if (mdev->state.disk > D_FAILED) { 1860 _drbd_set_state(_NS(mdev, disk, D_FAILED), CS_HARD, NULL); 1861 dev_err(DEV, 1862 "Local IO failed in %s. Detaching...\n", where); 1863 } 1864 break; 1865 } 1866 } 1867 1868 /** 1869 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers 1870 * @mdev: DRBD device. 1871 * @error: Error code passed to the IO completion callback 1872 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data 1873 * 1874 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED) 1875 */ 1876 #define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__) 1877 static inline void drbd_chk_io_error_(struct drbd_conf *mdev, 1878 int error, int forcedetach, const char *where) 1879 { 1880 if (error) { 1881 unsigned long flags; 1882 spin_lock_irqsave(&mdev->req_lock, flags); 1883 __drbd_chk_io_error_(mdev, forcedetach, where); 1884 spin_unlock_irqrestore(&mdev->req_lock, flags); 1885 } 1886 } 1887 1888 1889 /** 1890 * drbd_md_first_sector() - Returns the first sector number of the meta data area 1891 * @bdev: Meta data block device. 1892 * 1893 * BTW, for internal meta data, this happens to be the maximum capacity 1894 * we could agree upon with our peer node. 1895 */ 1896 static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev) 1897 { 1898 switch (bdev->dc.meta_dev_idx) { 1899 case DRBD_MD_INDEX_INTERNAL: 1900 case DRBD_MD_INDEX_FLEX_INT: 1901 return bdev->md.md_offset + bdev->md.bm_offset; 1902 case DRBD_MD_INDEX_FLEX_EXT: 1903 default: 1904 return bdev->md.md_offset; 1905 } 1906 } 1907 1908 /** 1909 * drbd_md_last_sector() - Return the last sector number of the meta data area 1910 * @bdev: Meta data block device. 1911 */ 1912 static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev) 1913 { 1914 switch (bdev->dc.meta_dev_idx) { 1915 case DRBD_MD_INDEX_INTERNAL: 1916 case DRBD_MD_INDEX_FLEX_INT: 1917 return bdev->md.md_offset + MD_AL_OFFSET - 1; 1918 case DRBD_MD_INDEX_FLEX_EXT: 1919 default: 1920 return bdev->md.md_offset + bdev->md.md_size_sect; 1921 } 1922 } 1923 1924 /* Returns the number of 512 byte sectors of the device */ 1925 static inline sector_t drbd_get_capacity(struct block_device *bdev) 1926 { 1927 /* return bdev ? get_capacity(bdev->bd_disk) : 0; */ 1928 return bdev ? i_size_read(bdev->bd_inode) >> 9 : 0; 1929 } 1930 1931 /** 1932 * drbd_get_max_capacity() - Returns the capacity we announce to out peer 1933 * @bdev: Meta data block device. 1934 * 1935 * returns the capacity we announce to out peer. we clip ourselves at the 1936 * various MAX_SECTORS, because if we don't, current implementation will 1937 * oops sooner or later 1938 */ 1939 static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev) 1940 { 1941 sector_t s; 1942 switch (bdev->dc.meta_dev_idx) { 1943 case DRBD_MD_INDEX_INTERNAL: 1944 case DRBD_MD_INDEX_FLEX_INT: 1945 s = drbd_get_capacity(bdev->backing_bdev) 1946 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1947 drbd_md_first_sector(bdev)) 1948 : 0; 1949 break; 1950 case DRBD_MD_INDEX_FLEX_EXT: 1951 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1952 drbd_get_capacity(bdev->backing_bdev)); 1953 /* clip at maximum size the meta device can support */ 1954 s = min_t(sector_t, s, 1955 BM_EXT_TO_SECT(bdev->md.md_size_sect 1956 - bdev->md.bm_offset)); 1957 break; 1958 default: 1959 s = min_t(sector_t, DRBD_MAX_SECTORS, 1960 drbd_get_capacity(bdev->backing_bdev)); 1961 } 1962 return s; 1963 } 1964 1965 /** 1966 * drbd_md_ss__() - Return the sector number of our meta data super block 1967 * @mdev: DRBD device. 1968 * @bdev: Meta data block device. 1969 */ 1970 static inline sector_t drbd_md_ss__(struct drbd_conf *mdev, 1971 struct drbd_backing_dev *bdev) 1972 { 1973 switch (bdev->dc.meta_dev_idx) { 1974 default: /* external, some index */ 1975 return MD_RESERVED_SECT * bdev->dc.meta_dev_idx; 1976 case DRBD_MD_INDEX_INTERNAL: 1977 /* with drbd08, internal meta data is always "flexible" */ 1978 case DRBD_MD_INDEX_FLEX_INT: 1979 /* sizeof(struct md_on_disk_07) == 4k 1980 * position: last 4k aligned block of 4k size */ 1981 if (!bdev->backing_bdev) { 1982 if (__ratelimit(&drbd_ratelimit_state)) { 1983 dev_err(DEV, "bdev->backing_bdev==NULL\n"); 1984 dump_stack(); 1985 } 1986 return 0; 1987 } 1988 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL) 1989 - MD_AL_OFFSET; 1990 case DRBD_MD_INDEX_FLEX_EXT: 1991 return 0; 1992 } 1993 } 1994 1995 static inline void 1996 drbd_queue_work_front(struct drbd_work_queue *q, struct drbd_work *w) 1997 { 1998 unsigned long flags; 1999 spin_lock_irqsave(&q->q_lock, flags); 2000 list_add(&w->list, &q->q); 2001 up(&q->s); /* within the spinlock, 2002 see comment near end of drbd_worker() */ 2003 spin_unlock_irqrestore(&q->q_lock, flags); 2004 } 2005 2006 static inline void 2007 drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 2008 { 2009 unsigned long flags; 2010 spin_lock_irqsave(&q->q_lock, flags); 2011 list_add_tail(&w->list, &q->q); 2012 up(&q->s); /* within the spinlock, 2013 see comment near end of drbd_worker() */ 2014 spin_unlock_irqrestore(&q->q_lock, flags); 2015 } 2016 2017 static inline void wake_asender(struct drbd_conf *mdev) 2018 { 2019 if (test_bit(SIGNAL_ASENDER, &mdev->flags)) 2020 force_sig(DRBD_SIG, mdev->asender.task); 2021 } 2022 2023 static inline void request_ping(struct drbd_conf *mdev) 2024 { 2025 set_bit(SEND_PING, &mdev->flags); 2026 wake_asender(mdev); 2027 } 2028 2029 static inline int drbd_send_short_cmd(struct drbd_conf *mdev, 2030 enum drbd_packets cmd) 2031 { 2032 struct p_header80 h; 2033 return drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, &h, sizeof(h)); 2034 } 2035 2036 static inline int drbd_send_ping(struct drbd_conf *mdev) 2037 { 2038 struct p_header80 h; 2039 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING, &h, sizeof(h)); 2040 } 2041 2042 static inline int drbd_send_ping_ack(struct drbd_conf *mdev) 2043 { 2044 struct p_header80 h; 2045 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING_ACK, &h, sizeof(h)); 2046 } 2047 2048 static inline void drbd_thread_stop(struct drbd_thread *thi) 2049 { 2050 _drbd_thread_stop(thi, false, true); 2051 } 2052 2053 static inline void drbd_thread_stop_nowait(struct drbd_thread *thi) 2054 { 2055 _drbd_thread_stop(thi, false, false); 2056 } 2057 2058 static inline void drbd_thread_restart_nowait(struct drbd_thread *thi) 2059 { 2060 _drbd_thread_stop(thi, true, false); 2061 } 2062 2063 /* counts how many answer packets packets we expect from our peer, 2064 * for either explicit application requests, 2065 * or implicit barrier packets as necessary. 2066 * increased: 2067 * w_send_barrier 2068 * _req_mod(req, queue_for_net_write or queue_for_net_read); 2069 * it is much easier and equally valid to count what we queue for the 2070 * worker, even before it actually was queued or send. 2071 * (drbd_make_request_common; recovery path on read io-error) 2072 * decreased: 2073 * got_BarrierAck (respective tl_clear, tl_clear_barrier) 2074 * _req_mod(req, data_received) 2075 * [from receive_DataReply] 2076 * _req_mod(req, write_acked_by_peer or recv_acked_by_peer or neg_acked) 2077 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)] 2078 * for some reason it is NOT decreased in got_NegAck, 2079 * but in the resulting cleanup code from report_params. 2080 * we should try to remember the reason for that... 2081 * _req_mod(req, send_failed or send_canceled) 2082 * _req_mod(req, connection_lost_while_pending) 2083 * [from tl_clear_barrier] 2084 */ 2085 static inline void inc_ap_pending(struct drbd_conf *mdev) 2086 { 2087 atomic_inc(&mdev->ap_pending_cnt); 2088 } 2089 2090 #define ERR_IF_CNT_IS_NEGATIVE(which) \ 2091 if (atomic_read(&mdev->which) < 0) \ 2092 dev_err(DEV, "in %s:%d: " #which " = %d < 0 !\n", \ 2093 __func__ , __LINE__ , \ 2094 atomic_read(&mdev->which)) 2095 2096 #define dec_ap_pending(mdev) do { \ 2097 typecheck(struct drbd_conf *, mdev); \ 2098 if (atomic_dec_and_test(&mdev->ap_pending_cnt)) \ 2099 wake_up(&mdev->misc_wait); \ 2100 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt); } while (0) 2101 2102 /* counts how many resync-related answers we still expect from the peer 2103 * increase decrease 2104 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY) 2105 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK with ID_SYNCER) 2106 * (or P_NEG_ACK with ID_SYNCER) 2107 */ 2108 static inline void inc_rs_pending(struct drbd_conf *mdev) 2109 { 2110 atomic_inc(&mdev->rs_pending_cnt); 2111 } 2112 2113 #define dec_rs_pending(mdev) do { \ 2114 typecheck(struct drbd_conf *, mdev); \ 2115 atomic_dec(&mdev->rs_pending_cnt); \ 2116 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt); } while (0) 2117 2118 /* counts how many answers we still need to send to the peer. 2119 * increased on 2120 * receive_Data unless protocol A; 2121 * we need to send a P_RECV_ACK (proto B) 2122 * or P_WRITE_ACK (proto C) 2123 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK 2124 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA 2125 * receive_Barrier_* we need to send a P_BARRIER_ACK 2126 */ 2127 static inline void inc_unacked(struct drbd_conf *mdev) 2128 { 2129 atomic_inc(&mdev->unacked_cnt); 2130 } 2131 2132 #define dec_unacked(mdev) do { \ 2133 typecheck(struct drbd_conf *, mdev); \ 2134 atomic_dec(&mdev->unacked_cnt); \ 2135 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 2136 2137 #define sub_unacked(mdev, n) do { \ 2138 typecheck(struct drbd_conf *, mdev); \ 2139 atomic_sub(n, &mdev->unacked_cnt); \ 2140 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 2141 2142 2143 static inline void put_net_conf(struct drbd_conf *mdev) 2144 { 2145 if (atomic_dec_and_test(&mdev->net_cnt)) 2146 wake_up(&mdev->net_cnt_wait); 2147 } 2148 2149 /** 2150 * get_net_conf() - Increase ref count on mdev->net_conf; Returns 0 if nothing there 2151 * @mdev: DRBD device. 2152 * 2153 * You have to call put_net_conf() when finished working with mdev->net_conf. 2154 */ 2155 static inline int get_net_conf(struct drbd_conf *mdev) 2156 { 2157 int have_net_conf; 2158 2159 atomic_inc(&mdev->net_cnt); 2160 have_net_conf = mdev->state.conn >= C_UNCONNECTED; 2161 if (!have_net_conf) 2162 put_net_conf(mdev); 2163 return have_net_conf; 2164 } 2165 2166 /** 2167 * get_ldev() - Increase the ref count on mdev->ldev. Returns 0 if there is no ldev 2168 * @M: DRBD device. 2169 * 2170 * You have to call put_ldev() when finished working with mdev->ldev. 2171 */ 2172 #define get_ldev(M) __cond_lock(local, _get_ldev_if_state(M,D_INCONSISTENT)) 2173 #define get_ldev_if_state(M,MINS) __cond_lock(local, _get_ldev_if_state(M,MINS)) 2174 2175 static inline void put_ldev(struct drbd_conf *mdev) 2176 { 2177 int i = atomic_dec_return(&mdev->local_cnt); 2178 2179 /* This may be called from some endio handler, 2180 * so we must not sleep here. */ 2181 2182 __release(local); 2183 D_ASSERT(i >= 0); 2184 if (i == 0) { 2185 if (mdev->state.disk == D_DISKLESS) 2186 /* even internal references gone, safe to destroy */ 2187 drbd_ldev_destroy(mdev); 2188 if (mdev->state.disk == D_FAILED) 2189 /* all application IO references gone. */ 2190 drbd_go_diskless(mdev); 2191 wake_up(&mdev->misc_wait); 2192 } 2193 } 2194 2195 #ifndef __CHECKER__ 2196 static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins) 2197 { 2198 int io_allowed; 2199 2200 /* never get a reference while D_DISKLESS */ 2201 if (mdev->state.disk == D_DISKLESS) 2202 return 0; 2203 2204 atomic_inc(&mdev->local_cnt); 2205 io_allowed = (mdev->state.disk >= mins); 2206 if (!io_allowed) 2207 put_ldev(mdev); 2208 return io_allowed; 2209 } 2210 #else 2211 extern int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins); 2212 #endif 2213 2214 /* you must have an "get_ldev" reference */ 2215 static inline void drbd_get_syncer_progress(struct drbd_conf *mdev, 2216 unsigned long *bits_left, unsigned int *per_mil_done) 2217 { 2218 /* this is to break it at compile time when we change that, in case we 2219 * want to support more than (1<<32) bits on a 32bit arch. */ 2220 typecheck(unsigned long, mdev->rs_total); 2221 2222 /* note: both rs_total and rs_left are in bits, i.e. in 2223 * units of BM_BLOCK_SIZE. 2224 * for the percentage, we don't care. */ 2225 2226 if (mdev->state.conn == C_VERIFY_S || mdev->state.conn == C_VERIFY_T) 2227 *bits_left = mdev->ov_left; 2228 else 2229 *bits_left = drbd_bm_total_weight(mdev) - mdev->rs_failed; 2230 /* >> 10 to prevent overflow, 2231 * +1 to prevent division by zero */ 2232 if (*bits_left > mdev->rs_total) { 2233 /* doh. maybe a logic bug somewhere. 2234 * may also be just a race condition 2235 * between this and a disconnect during sync. 2236 * for now, just prevent in-kernel buffer overflow. 2237 */ 2238 smp_rmb(); 2239 dev_warn(DEV, "cs:%s rs_left=%lu > rs_total=%lu (rs_failed %lu)\n", 2240 drbd_conn_str(mdev->state.conn), 2241 *bits_left, mdev->rs_total, mdev->rs_failed); 2242 *per_mil_done = 0; 2243 } else { 2244 /* Make sure the division happens in long context. 2245 * We allow up to one petabyte storage right now, 2246 * at a granularity of 4k per bit that is 2**38 bits. 2247 * After shift right and multiplication by 1000, 2248 * this should still fit easily into a 32bit long, 2249 * so we don't need a 64bit division on 32bit arch. 2250 * Note: currently we don't support such large bitmaps on 32bit 2251 * arch anyways, but no harm done to be prepared for it here. 2252 */ 2253 unsigned int shift = mdev->rs_total > UINT_MAX ? 16 : 10; 2254 unsigned long left = *bits_left >> shift; 2255 unsigned long total = 1UL + (mdev->rs_total >> shift); 2256 unsigned long tmp = 1000UL - left * 1000UL/total; 2257 *per_mil_done = tmp; 2258 } 2259 } 2260 2261 2262 /* this throttles on-the-fly application requests 2263 * according to max_buffers settings; 2264 * maybe re-implement using semaphores? */ 2265 static inline int drbd_get_max_buffers(struct drbd_conf *mdev) 2266 { 2267 int mxb = 1000000; /* arbitrary limit on open requests */ 2268 if (get_net_conf(mdev)) { 2269 mxb = mdev->net_conf->max_buffers; 2270 put_net_conf(mdev); 2271 } 2272 return mxb; 2273 } 2274 2275 static inline int drbd_state_is_stable(struct drbd_conf *mdev) 2276 { 2277 union drbd_state s = mdev->state; 2278 2279 /* DO NOT add a default clause, we want the compiler to warn us 2280 * for any newly introduced state we may have forgotten to add here */ 2281 2282 switch ((enum drbd_conns)s.conn) { 2283 /* new io only accepted when there is no connection, ... */ 2284 case C_STANDALONE: 2285 case C_WF_CONNECTION: 2286 /* ... or there is a well established connection. */ 2287 case C_CONNECTED: 2288 case C_SYNC_SOURCE: 2289 case C_SYNC_TARGET: 2290 case C_VERIFY_S: 2291 case C_VERIFY_T: 2292 case C_PAUSED_SYNC_S: 2293 case C_PAUSED_SYNC_T: 2294 case C_AHEAD: 2295 case C_BEHIND: 2296 /* transitional states, IO allowed */ 2297 case C_DISCONNECTING: 2298 case C_UNCONNECTED: 2299 case C_TIMEOUT: 2300 case C_BROKEN_PIPE: 2301 case C_NETWORK_FAILURE: 2302 case C_PROTOCOL_ERROR: 2303 case C_TEAR_DOWN: 2304 case C_WF_REPORT_PARAMS: 2305 case C_STARTING_SYNC_S: 2306 case C_STARTING_SYNC_T: 2307 break; 2308 2309 /* Allow IO in BM exchange states with new protocols */ 2310 case C_WF_BITMAP_S: 2311 if (mdev->agreed_pro_version < 96) 2312 return 0; 2313 break; 2314 2315 /* no new io accepted in these states */ 2316 case C_WF_BITMAP_T: 2317 case C_WF_SYNC_UUID: 2318 case C_MASK: 2319 /* not "stable" */ 2320 return 0; 2321 } 2322 2323 switch ((enum drbd_disk_state)s.disk) { 2324 case D_DISKLESS: 2325 case D_INCONSISTENT: 2326 case D_OUTDATED: 2327 case D_CONSISTENT: 2328 case D_UP_TO_DATE: 2329 case D_FAILED: 2330 /* disk state is stable as well. */ 2331 break; 2332 2333 /* no new io accepted during tansitional states */ 2334 case D_ATTACHING: 2335 case D_NEGOTIATING: 2336 case D_UNKNOWN: 2337 case D_MASK: 2338 /* not "stable" */ 2339 return 0; 2340 } 2341 2342 return 1; 2343 } 2344 2345 static inline int is_susp(union drbd_state s) 2346 { 2347 return s.susp || s.susp_nod || s.susp_fen; 2348 } 2349 2350 static inline bool may_inc_ap_bio(struct drbd_conf *mdev) 2351 { 2352 int mxb = drbd_get_max_buffers(mdev); 2353 2354 if (is_susp(mdev->state)) 2355 return false; 2356 if (test_bit(SUSPEND_IO, &mdev->flags)) 2357 return false; 2358 2359 /* to avoid potential deadlock or bitmap corruption, 2360 * in various places, we only allow new application io 2361 * to start during "stable" states. */ 2362 2363 /* no new io accepted when attaching or detaching the disk */ 2364 if (!drbd_state_is_stable(mdev)) 2365 return false; 2366 2367 /* since some older kernels don't have atomic_add_unless, 2368 * and we are within the spinlock anyways, we have this workaround. */ 2369 if (atomic_read(&mdev->ap_bio_cnt) > mxb) 2370 return false; 2371 if (test_bit(BITMAP_IO, &mdev->flags)) 2372 return false; 2373 return true; 2374 } 2375 2376 static inline bool inc_ap_bio_cond(struct drbd_conf *mdev, int count) 2377 { 2378 bool rv = false; 2379 2380 spin_lock_irq(&mdev->req_lock); 2381 rv = may_inc_ap_bio(mdev); 2382 if (rv) 2383 atomic_add(count, &mdev->ap_bio_cnt); 2384 spin_unlock_irq(&mdev->req_lock); 2385 2386 return rv; 2387 } 2388 2389 static inline void inc_ap_bio(struct drbd_conf *mdev, int count) 2390 { 2391 /* we wait here 2392 * as long as the device is suspended 2393 * until the bitmap is no longer on the fly during connection 2394 * handshake as long as we would exeed the max_buffer limit. 2395 * 2396 * to avoid races with the reconnect code, 2397 * we need to atomic_inc within the spinlock. */ 2398 2399 wait_event(mdev->misc_wait, inc_ap_bio_cond(mdev, count)); 2400 } 2401 2402 static inline void dec_ap_bio(struct drbd_conf *mdev) 2403 { 2404 int mxb = drbd_get_max_buffers(mdev); 2405 int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt); 2406 2407 D_ASSERT(ap_bio >= 0); 2408 /* this currently does wake_up for every dec_ap_bio! 2409 * maybe rather introduce some type of hysteresis? 2410 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */ 2411 if (ap_bio < mxb) 2412 wake_up(&mdev->misc_wait); 2413 if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) { 2414 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags)) 2415 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w); 2416 } 2417 } 2418 2419 static inline int drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val) 2420 { 2421 int changed = mdev->ed_uuid != val; 2422 mdev->ed_uuid = val; 2423 return changed; 2424 } 2425 2426 static inline int seq_cmp(u32 a, u32 b) 2427 { 2428 /* we assume wrap around at 32bit. 2429 * for wrap around at 24bit (old atomic_t), 2430 * we'd have to 2431 * a <<= 8; b <<= 8; 2432 */ 2433 return (s32)(a) - (s32)(b); 2434 } 2435 #define seq_lt(a, b) (seq_cmp((a), (b)) < 0) 2436 #define seq_gt(a, b) (seq_cmp((a), (b)) > 0) 2437 #define seq_ge(a, b) (seq_cmp((a), (b)) >= 0) 2438 #define seq_le(a, b) (seq_cmp((a), (b)) <= 0) 2439 /* CAUTION: please no side effects in arguments! */ 2440 #define seq_max(a, b) ((u32)(seq_gt((a), (b)) ? (a) : (b))) 2441 2442 static inline void update_peer_seq(struct drbd_conf *mdev, unsigned int new_seq) 2443 { 2444 unsigned int m; 2445 spin_lock(&mdev->peer_seq_lock); 2446 m = seq_max(mdev->peer_seq, new_seq); 2447 mdev->peer_seq = m; 2448 spin_unlock(&mdev->peer_seq_lock); 2449 if (m == new_seq) 2450 wake_up(&mdev->seq_wait); 2451 } 2452 2453 static inline void drbd_update_congested(struct drbd_conf *mdev) 2454 { 2455 struct sock *sk = mdev->data.socket->sk; 2456 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5) 2457 set_bit(NET_CONGESTED, &mdev->flags); 2458 } 2459 2460 static inline int drbd_queue_order_type(struct drbd_conf *mdev) 2461 { 2462 /* sorry, we currently have no working implementation 2463 * of distributed TCQ stuff */ 2464 #ifndef QUEUE_ORDERED_NONE 2465 #define QUEUE_ORDERED_NONE 0 2466 #endif 2467 return QUEUE_ORDERED_NONE; 2468 } 2469 2470 static inline void drbd_md_flush(struct drbd_conf *mdev) 2471 { 2472 int r; 2473 2474 if (test_bit(MD_NO_FUA, &mdev->flags)) 2475 return; 2476 2477 r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL); 2478 if (r) { 2479 set_bit(MD_NO_FUA, &mdev->flags); 2480 dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r); 2481 } 2482 } 2483 2484 #endif 2485