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 #include <linux/prefetch.h> 46 47 #ifdef __CHECKER__ 48 # define __protected_by(x) __attribute__((require_context(x,1,999,"rdwr"))) 49 # define __protected_read_by(x) __attribute__((require_context(x,1,999,"read"))) 50 # define __protected_write_by(x) __attribute__((require_context(x,1,999,"write"))) 51 # define __must_hold(x) __attribute__((context(x,1,1), require_context(x,1,999,"call"))) 52 #else 53 # define __protected_by(x) 54 # define __protected_read_by(x) 55 # define __protected_write_by(x) 56 # define __must_hold(x) 57 #endif 58 59 #define __no_warn(lock, stmt) do { __acquire(lock); stmt; __release(lock); } while (0) 60 61 /* module parameter, defined in drbd_main.c */ 62 extern unsigned int minor_count; 63 extern int disable_sendpage; 64 extern int allow_oos; 65 extern unsigned int cn_idx; 66 67 #ifdef CONFIG_DRBD_FAULT_INJECTION 68 extern int enable_faults; 69 extern int fault_rate; 70 extern int fault_devs; 71 #endif 72 73 extern char usermode_helper[]; 74 75 76 /* I don't remember why XCPU ... 77 * This is used to wake the asender, 78 * and to interrupt sending the sending task 79 * on disconnect. 80 */ 81 #define DRBD_SIG SIGXCPU 82 83 /* This is used to stop/restart our threads. 84 * Cannot use SIGTERM nor SIGKILL, since these 85 * are sent out by init on runlevel changes 86 * I choose SIGHUP for now. 87 */ 88 #define DRBD_SIGKILL SIGHUP 89 90 /* All EEs on the free list should have ID_VACANT (== 0) 91 * freshly allocated EEs get !ID_VACANT (== 1) 92 * so if it says "cannot dereference null pointer at address 0x00000001", 93 * it is most likely one of these :( */ 94 95 #define ID_IN_SYNC (4711ULL) 96 #define ID_OUT_OF_SYNC (4712ULL) 97 98 #define ID_SYNCER (-1ULL) 99 #define ID_VACANT 0 100 #define is_syncer_block_id(id) ((id) == ID_SYNCER) 101 #define UUID_NEW_BM_OFFSET ((u64)0x0001000000000000ULL) 102 103 struct drbd_conf; 104 105 106 /* to shorten dev_warn(DEV, "msg"); and relatives statements */ 107 #define DEV (disk_to_dev(mdev->vdisk)) 108 109 #define D_ASSERT(exp) if (!(exp)) \ 110 dev_err(DEV, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__) 111 112 #define ERR_IF(exp) if (({ \ 113 int _b = (exp) != 0; \ 114 if (_b) dev_err(DEV, "ASSERT FAILED: %s: (%s) in %s:%d\n", \ 115 __func__, #exp, __FILE__, __LINE__); \ 116 _b; \ 117 })) 118 119 /* Defines to control fault insertion */ 120 enum { 121 DRBD_FAULT_MD_WR = 0, /* meta data write */ 122 DRBD_FAULT_MD_RD = 1, /* read */ 123 DRBD_FAULT_RS_WR = 2, /* resync */ 124 DRBD_FAULT_RS_RD = 3, 125 DRBD_FAULT_DT_WR = 4, /* data */ 126 DRBD_FAULT_DT_RD = 5, 127 DRBD_FAULT_DT_RA = 6, /* data read ahead */ 128 DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */ 129 DRBD_FAULT_AL_EE = 8, /* alloc ee */ 130 DRBD_FAULT_RECEIVE = 9, /* Changes some bytes upon receiving a [rs]data block */ 131 132 DRBD_FAULT_MAX, 133 }; 134 135 extern unsigned int 136 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type); 137 138 static inline int 139 drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) { 140 #ifdef CONFIG_DRBD_FAULT_INJECTION 141 return fault_rate && 142 (enable_faults & (1<<type)) && 143 _drbd_insert_fault(mdev, type); 144 #else 145 return 0; 146 #endif 147 } 148 149 /* integer division, round _UP_ to the next integer */ 150 #define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0)) 151 /* usual integer division */ 152 #define div_floor(A, B) ((A)/(B)) 153 154 /* drbd_meta-data.c (still in drbd_main.c) */ 155 /* 4th incarnation of the disk layout. */ 156 #define DRBD_MD_MAGIC (DRBD_MAGIC+4) 157 158 extern struct drbd_conf **minor_table; 159 extern struct ratelimit_state drbd_ratelimit_state; 160 161 /* on the wire */ 162 enum drbd_packets { 163 /* receiver (data socket) */ 164 P_DATA = 0x00, 165 P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */ 166 P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */ 167 P_BARRIER = 0x03, 168 P_BITMAP = 0x04, 169 P_BECOME_SYNC_TARGET = 0x05, 170 P_BECOME_SYNC_SOURCE = 0x06, 171 P_UNPLUG_REMOTE = 0x07, /* Used at various times to hint the peer */ 172 P_DATA_REQUEST = 0x08, /* Used to ask for a data block */ 173 P_RS_DATA_REQUEST = 0x09, /* Used to ask for a data block for resync */ 174 P_SYNC_PARAM = 0x0a, 175 P_PROTOCOL = 0x0b, 176 P_UUIDS = 0x0c, 177 P_SIZES = 0x0d, 178 P_STATE = 0x0e, 179 P_SYNC_UUID = 0x0f, 180 P_AUTH_CHALLENGE = 0x10, 181 P_AUTH_RESPONSE = 0x11, 182 P_STATE_CHG_REQ = 0x12, 183 184 /* asender (meta socket */ 185 P_PING = 0x13, 186 P_PING_ACK = 0x14, 187 P_RECV_ACK = 0x15, /* Used in protocol B */ 188 P_WRITE_ACK = 0x16, /* Used in protocol C */ 189 P_RS_WRITE_ACK = 0x17, /* Is a P_WRITE_ACK, additionally call set_in_sync(). */ 190 P_DISCARD_ACK = 0x18, /* Used in proto C, two-primaries conflict detection */ 191 P_NEG_ACK = 0x19, /* Sent if local disk is unusable */ 192 P_NEG_DREPLY = 0x1a, /* Local disk is broken... */ 193 P_NEG_RS_DREPLY = 0x1b, /* Local disk is broken... */ 194 P_BARRIER_ACK = 0x1c, 195 P_STATE_CHG_REPLY = 0x1d, 196 197 /* "new" commands, no longer fitting into the ordering scheme above */ 198 199 P_OV_REQUEST = 0x1e, /* data socket */ 200 P_OV_REPLY = 0x1f, 201 P_OV_RESULT = 0x20, /* meta socket */ 202 P_CSUM_RS_REQUEST = 0x21, /* data socket */ 203 P_RS_IS_IN_SYNC = 0x22, /* meta socket */ 204 P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */ 205 P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */ 206 /* P_CKPT_FENCE_REQ = 0x25, * currently reserved for protocol D */ 207 /* P_CKPT_DISABLE_REQ = 0x26, * currently reserved for protocol D */ 208 P_DELAY_PROBE = 0x27, /* is used on BOTH sockets */ 209 P_OUT_OF_SYNC = 0x28, /* Mark as out of sync (Outrunning), data socket */ 210 P_RS_CANCEL = 0x29, /* meta: Used to cancel RS_DATA_REQUEST packet by SyncSource */ 211 212 P_MAX_CMD = 0x2A, 213 P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */ 214 P_MAX_OPT_CMD = 0x101, 215 216 /* special command ids for handshake */ 217 218 P_HAND_SHAKE_M = 0xfff1, /* First Packet on the MetaSock */ 219 P_HAND_SHAKE_S = 0xfff2, /* First Packet on the Socket */ 220 221 P_HAND_SHAKE = 0xfffe /* FIXED for the next century! */ 222 }; 223 224 static inline const char *cmdname(enum drbd_packets cmd) 225 { 226 /* THINK may need to become several global tables 227 * when we want to support more than 228 * one PRO_VERSION */ 229 static const char *cmdnames[] = { 230 [P_DATA] = "Data", 231 [P_DATA_REPLY] = "DataReply", 232 [P_RS_DATA_REPLY] = "RSDataReply", 233 [P_BARRIER] = "Barrier", 234 [P_BITMAP] = "ReportBitMap", 235 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget", 236 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource", 237 [P_UNPLUG_REMOTE] = "UnplugRemote", 238 [P_DATA_REQUEST] = "DataRequest", 239 [P_RS_DATA_REQUEST] = "RSDataRequest", 240 [P_SYNC_PARAM] = "SyncParam", 241 [P_SYNC_PARAM89] = "SyncParam89", 242 [P_PROTOCOL] = "ReportProtocol", 243 [P_UUIDS] = "ReportUUIDs", 244 [P_SIZES] = "ReportSizes", 245 [P_STATE] = "ReportState", 246 [P_SYNC_UUID] = "ReportSyncUUID", 247 [P_AUTH_CHALLENGE] = "AuthChallenge", 248 [P_AUTH_RESPONSE] = "AuthResponse", 249 [P_PING] = "Ping", 250 [P_PING_ACK] = "PingAck", 251 [P_RECV_ACK] = "RecvAck", 252 [P_WRITE_ACK] = "WriteAck", 253 [P_RS_WRITE_ACK] = "RSWriteAck", 254 [P_DISCARD_ACK] = "DiscardAck", 255 [P_NEG_ACK] = "NegAck", 256 [P_NEG_DREPLY] = "NegDReply", 257 [P_NEG_RS_DREPLY] = "NegRSDReply", 258 [P_BARRIER_ACK] = "BarrierAck", 259 [P_STATE_CHG_REQ] = "StateChgRequest", 260 [P_STATE_CHG_REPLY] = "StateChgReply", 261 [P_OV_REQUEST] = "OVRequest", 262 [P_OV_REPLY] = "OVReply", 263 [P_OV_RESULT] = "OVResult", 264 [P_CSUM_RS_REQUEST] = "CsumRSRequest", 265 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync", 266 [P_COMPRESSED_BITMAP] = "CBitmap", 267 [P_DELAY_PROBE] = "DelayProbe", 268 [P_OUT_OF_SYNC] = "OutOfSync", 269 [P_MAX_CMD] = NULL, 270 }; 271 272 if (cmd == P_HAND_SHAKE_M) 273 return "HandShakeM"; 274 if (cmd == P_HAND_SHAKE_S) 275 return "HandShakeS"; 276 if (cmd == P_HAND_SHAKE) 277 return "HandShake"; 278 if (cmd >= P_MAX_CMD) 279 return "Unknown"; 280 return cmdnames[cmd]; 281 } 282 283 /* for sending/receiving the bitmap, 284 * possibly in some encoding scheme */ 285 struct bm_xfer_ctx { 286 /* "const" 287 * stores total bits and long words 288 * of the bitmap, so we don't need to 289 * call the accessor functions over and again. */ 290 unsigned long bm_bits; 291 unsigned long bm_words; 292 /* during xfer, current position within the bitmap */ 293 unsigned long bit_offset; 294 unsigned long word_offset; 295 296 /* statistics; index: (h->command == P_BITMAP) */ 297 unsigned packets[2]; 298 unsigned bytes[2]; 299 }; 300 301 extern void INFO_bm_xfer_stats(struct drbd_conf *mdev, 302 const char *direction, struct bm_xfer_ctx *c); 303 304 static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c) 305 { 306 /* word_offset counts "native long words" (32 or 64 bit), 307 * aligned at 64 bit. 308 * Encoded packet may end at an unaligned bit offset. 309 * In case a fallback clear text packet is transmitted in 310 * between, we adjust this offset back to the last 64bit 311 * aligned "native long word", which makes coding and decoding 312 * the plain text bitmap much more convenient. */ 313 #if BITS_PER_LONG == 64 314 c->word_offset = c->bit_offset >> 6; 315 #elif BITS_PER_LONG == 32 316 c->word_offset = c->bit_offset >> 5; 317 c->word_offset &= ~(1UL); 318 #else 319 # error "unsupported BITS_PER_LONG" 320 #endif 321 } 322 323 #ifndef __packed 324 #define __packed __attribute__((packed)) 325 #endif 326 327 /* This is the layout for a packet on the wire. 328 * The byteorder is the network byte order. 329 * (except block_id and barrier fields. 330 * these are pointers to local structs 331 * and have no relevance for the partner, 332 * which just echoes them as received.) 333 * 334 * NOTE that the payload starts at a long aligned offset, 335 * regardless of 32 or 64 bit arch! 336 */ 337 struct p_header80 { 338 u32 magic; 339 u16 command; 340 u16 length; /* bytes of data after this header */ 341 u8 payload[0]; 342 } __packed; 343 344 /* Header for big packets, Used for data packets exceeding 64kB */ 345 struct p_header95 { 346 u16 magic; /* use DRBD_MAGIC_BIG here */ 347 u16 command; 348 u32 length; /* Use only 24 bits of that. Ignore the highest 8 bit. */ 349 u8 payload[0]; 350 } __packed; 351 352 union p_header { 353 struct p_header80 h80; 354 struct p_header95 h95; 355 }; 356 357 /* 358 * short commands, packets without payload, plain p_header: 359 * P_PING 360 * P_PING_ACK 361 * P_BECOME_SYNC_TARGET 362 * P_BECOME_SYNC_SOURCE 363 * P_UNPLUG_REMOTE 364 */ 365 366 /* 367 * commands with out-of-struct payload: 368 * P_BITMAP (no additional fields) 369 * P_DATA, P_DATA_REPLY (see p_data) 370 * P_COMPRESSED_BITMAP (see receive_compressed_bitmap) 371 */ 372 373 /* these defines must not be changed without changing the protocol version */ 374 #define DP_HARDBARRIER 1 /* depricated */ 375 #define DP_RW_SYNC 2 /* equals REQ_SYNC */ 376 #define DP_MAY_SET_IN_SYNC 4 377 #define DP_UNPLUG 8 /* not used anymore */ 378 #define DP_FUA 16 /* equals REQ_FUA */ 379 #define DP_FLUSH 32 /* equals REQ_FLUSH */ 380 #define DP_DISCARD 64 /* equals REQ_DISCARD */ 381 382 struct p_data { 383 union p_header head; 384 u64 sector; /* 64 bits sector number */ 385 u64 block_id; /* to identify the request in protocol B&C */ 386 u32 seq_num; 387 u32 dp_flags; 388 } __packed; 389 390 /* 391 * commands which share a struct: 392 * p_block_ack: 393 * P_RECV_ACK (proto B), P_WRITE_ACK (proto C), 394 * P_DISCARD_ACK (proto C, two-primaries conflict detection) 395 * p_block_req: 396 * P_DATA_REQUEST, P_RS_DATA_REQUEST 397 */ 398 struct p_block_ack { 399 struct p_header80 head; 400 u64 sector; 401 u64 block_id; 402 u32 blksize; 403 u32 seq_num; 404 } __packed; 405 406 407 struct p_block_req { 408 struct p_header80 head; 409 u64 sector; 410 u64 block_id; 411 u32 blksize; 412 u32 pad; /* to multiple of 8 Byte */ 413 } __packed; 414 415 /* 416 * commands with their own struct for additional fields: 417 * P_HAND_SHAKE 418 * P_BARRIER 419 * P_BARRIER_ACK 420 * P_SYNC_PARAM 421 * ReportParams 422 */ 423 424 struct p_handshake { 425 struct p_header80 head; /* 8 bytes */ 426 u32 protocol_min; 427 u32 feature_flags; 428 u32 protocol_max; 429 430 /* should be more than enough for future enhancements 431 * for now, feature_flags and the reserverd array shall be zero. 432 */ 433 434 u32 _pad; 435 u64 reserverd[7]; 436 } __packed; 437 /* 80 bytes, FIXED for the next century */ 438 439 struct p_barrier { 440 struct p_header80 head; 441 u32 barrier; /* barrier number _handle_ only */ 442 u32 pad; /* to multiple of 8 Byte */ 443 } __packed; 444 445 struct p_barrier_ack { 446 struct p_header80 head; 447 u32 barrier; 448 u32 set_size; 449 } __packed; 450 451 struct p_rs_param { 452 struct p_header80 head; 453 u32 rate; 454 455 /* Since protocol version 88 and higher. */ 456 char verify_alg[0]; 457 } __packed; 458 459 struct p_rs_param_89 { 460 struct p_header80 head; 461 u32 rate; 462 /* protocol version 89: */ 463 char verify_alg[SHARED_SECRET_MAX]; 464 char csums_alg[SHARED_SECRET_MAX]; 465 } __packed; 466 467 struct p_rs_param_95 { 468 struct p_header80 head; 469 u32 rate; 470 char verify_alg[SHARED_SECRET_MAX]; 471 char csums_alg[SHARED_SECRET_MAX]; 472 u32 c_plan_ahead; 473 u32 c_delay_target; 474 u32 c_fill_target; 475 u32 c_max_rate; 476 } __packed; 477 478 enum drbd_conn_flags { 479 CF_WANT_LOSE = 1, 480 CF_DRY_RUN = 2, 481 }; 482 483 struct p_protocol { 484 struct p_header80 head; 485 u32 protocol; 486 u32 after_sb_0p; 487 u32 after_sb_1p; 488 u32 after_sb_2p; 489 u32 conn_flags; 490 u32 two_primaries; 491 492 /* Since protocol version 87 and higher. */ 493 char integrity_alg[0]; 494 495 } __packed; 496 497 struct p_uuids { 498 struct p_header80 head; 499 u64 uuid[UI_EXTENDED_SIZE]; 500 } __packed; 501 502 struct p_rs_uuid { 503 struct p_header80 head; 504 u64 uuid; 505 } __packed; 506 507 struct p_sizes { 508 struct p_header80 head; 509 u64 d_size; /* size of disk */ 510 u64 u_size; /* user requested size */ 511 u64 c_size; /* current exported size */ 512 u32 max_bio_size; /* Maximal size of a BIO */ 513 u16 queue_order_type; /* not yet implemented in DRBD*/ 514 u16 dds_flags; /* use enum dds_flags here. */ 515 } __packed; 516 517 struct p_state { 518 struct p_header80 head; 519 u32 state; 520 } __packed; 521 522 struct p_req_state { 523 struct p_header80 head; 524 u32 mask; 525 u32 val; 526 } __packed; 527 528 struct p_req_state_reply { 529 struct p_header80 head; 530 u32 retcode; 531 } __packed; 532 533 struct p_drbd06_param { 534 u64 size; 535 u32 state; 536 u32 blksize; 537 u32 protocol; 538 u32 version; 539 u32 gen_cnt[5]; 540 u32 bit_map_gen[5]; 541 } __packed; 542 543 struct p_discard { 544 struct p_header80 head; 545 u64 block_id; 546 u32 seq_num; 547 u32 pad; 548 } __packed; 549 550 struct p_block_desc { 551 struct p_header80 head; 552 u64 sector; 553 u32 blksize; 554 u32 pad; /* to multiple of 8 Byte */ 555 } __packed; 556 557 /* Valid values for the encoding field. 558 * Bump proto version when changing this. */ 559 enum drbd_bitmap_code { 560 /* RLE_VLI_Bytes = 0, 561 * and other bit variants had been defined during 562 * algorithm evaluation. */ 563 RLE_VLI_Bits = 2, 564 }; 565 566 struct p_compressed_bm { 567 struct p_header80 head; 568 /* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code 569 * (encoding & 0x80): polarity (set/unset) of first runlength 570 * ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits 571 * used to pad up to head.length bytes 572 */ 573 u8 encoding; 574 575 u8 code[0]; 576 } __packed; 577 578 struct p_delay_probe93 { 579 struct p_header80 head; 580 u32 seq_num; /* sequence number to match the two probe packets */ 581 u32 offset; /* usecs the probe got sent after the reference time point */ 582 } __packed; 583 584 /* DCBP: Drbd Compressed Bitmap Packet ... */ 585 static inline enum drbd_bitmap_code 586 DCBP_get_code(struct p_compressed_bm *p) 587 { 588 return (enum drbd_bitmap_code)(p->encoding & 0x0f); 589 } 590 591 static inline void 592 DCBP_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code) 593 { 594 BUG_ON(code & ~0xf); 595 p->encoding = (p->encoding & ~0xf) | code; 596 } 597 598 static inline int 599 DCBP_get_start(struct p_compressed_bm *p) 600 { 601 return (p->encoding & 0x80) != 0; 602 } 603 604 static inline void 605 DCBP_set_start(struct p_compressed_bm *p, int set) 606 { 607 p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0); 608 } 609 610 static inline int 611 DCBP_get_pad_bits(struct p_compressed_bm *p) 612 { 613 return (p->encoding >> 4) & 0x7; 614 } 615 616 static inline void 617 DCBP_set_pad_bits(struct p_compressed_bm *p, int n) 618 { 619 BUG_ON(n & ~0x7); 620 p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4); 621 } 622 623 /* one bitmap packet, including the p_header, 624 * should fit within one _architecture independend_ page. 625 * so we need to use the fixed size 4KiB page size 626 * most architectures have used for a long time. 627 */ 628 #define BM_PACKET_PAYLOAD_BYTES (4096 - sizeof(struct p_header80)) 629 #define BM_PACKET_WORDS (BM_PACKET_PAYLOAD_BYTES/sizeof(long)) 630 #define BM_PACKET_VLI_BYTES_MAX (4096 - sizeof(struct p_compressed_bm)) 631 #if (PAGE_SIZE < 4096) 632 /* drbd_send_bitmap / receive_bitmap would break horribly */ 633 #error "PAGE_SIZE too small" 634 #endif 635 636 union p_polymorph { 637 union p_header header; 638 struct p_handshake handshake; 639 struct p_data data; 640 struct p_block_ack block_ack; 641 struct p_barrier barrier; 642 struct p_barrier_ack barrier_ack; 643 struct p_rs_param_89 rs_param_89; 644 struct p_rs_param_95 rs_param_95; 645 struct p_protocol protocol; 646 struct p_sizes sizes; 647 struct p_uuids uuids; 648 struct p_state state; 649 struct p_req_state req_state; 650 struct p_req_state_reply req_state_reply; 651 struct p_block_req block_req; 652 struct p_delay_probe93 delay_probe93; 653 struct p_rs_uuid rs_uuid; 654 struct p_block_desc block_desc; 655 } __packed; 656 657 /**********************************************************************/ 658 enum drbd_thread_state { 659 None, 660 Running, 661 Exiting, 662 Restarting 663 }; 664 665 struct drbd_thread { 666 spinlock_t t_lock; 667 struct task_struct *task; 668 struct completion stop; 669 enum drbd_thread_state t_state; 670 int (*function) (struct drbd_thread *); 671 struct drbd_conf *mdev; 672 int reset_cpu_mask; 673 }; 674 675 static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi) 676 { 677 /* THINK testing the t_state seems to be uncritical in all cases 678 * (but thread_{start,stop}), so we can read it *without* the lock. 679 * --lge */ 680 681 smp_rmb(); 682 return thi->t_state; 683 } 684 685 struct drbd_work; 686 typedef int (*drbd_work_cb)(struct drbd_conf *, struct drbd_work *, int cancel); 687 struct drbd_work { 688 struct list_head list; 689 drbd_work_cb cb; 690 }; 691 692 struct drbd_tl_epoch; 693 struct drbd_request { 694 struct drbd_work w; 695 struct drbd_conf *mdev; 696 697 /* if local IO is not allowed, will be NULL. 698 * if local IO _is_ allowed, holds the locally submitted bio clone, 699 * or, after local IO completion, the ERR_PTR(error). 700 * see drbd_endio_pri(). */ 701 struct bio *private_bio; 702 703 struct hlist_node collision; 704 sector_t sector; 705 unsigned int size; 706 unsigned int epoch; /* barrier_nr */ 707 708 /* barrier_nr: used to check on "completion" whether this req was in 709 * the current epoch, and we therefore have to close it, 710 * starting a new epoch... 711 */ 712 713 struct list_head tl_requests; /* ring list in the transfer log */ 714 struct bio *master_bio; /* master bio pointer */ 715 unsigned long rq_state; /* see comments above _req_mod() */ 716 int seq_num; 717 unsigned long start_time; 718 }; 719 720 struct drbd_tl_epoch { 721 struct drbd_work w; 722 struct list_head requests; /* requests before */ 723 struct drbd_tl_epoch *next; /* pointer to the next barrier */ 724 unsigned int br_number; /* the barriers identifier. */ 725 int n_writes; /* number of requests attached before this barrier */ 726 }; 727 728 struct drbd_request; 729 730 /* These Tl_epoch_entries may be in one of 6 lists: 731 active_ee .. data packet being written 732 sync_ee .. syncer block being written 733 done_ee .. block written, need to send P_WRITE_ACK 734 read_ee .. [RS]P_DATA_REQUEST being read 735 */ 736 737 struct drbd_epoch { 738 struct list_head list; 739 unsigned int barrier_nr; 740 atomic_t epoch_size; /* increased on every request added. */ 741 atomic_t active; /* increased on every req. added, and dec on every finished. */ 742 unsigned long flags; 743 }; 744 745 /* drbd_epoch flag bits */ 746 enum { 747 DE_HAVE_BARRIER_NUMBER, 748 }; 749 750 enum epoch_event { 751 EV_PUT, 752 EV_GOT_BARRIER_NR, 753 EV_BECAME_LAST, 754 EV_CLEANUP = 32, /* used as flag */ 755 }; 756 757 struct drbd_wq_barrier { 758 struct drbd_work w; 759 struct completion done; 760 }; 761 762 struct digest_info { 763 int digest_size; 764 void *digest; 765 }; 766 767 struct drbd_epoch_entry { 768 struct drbd_work w; 769 struct hlist_node collision; 770 struct drbd_epoch *epoch; /* for writes */ 771 struct drbd_conf *mdev; 772 struct page *pages; 773 atomic_t pending_bios; 774 unsigned int size; 775 /* see comments on ee flag bits below */ 776 unsigned long flags; 777 sector_t sector; 778 union { 779 u64 block_id; 780 struct digest_info *digest; 781 }; 782 }; 783 784 /* ee flag bits. 785 * While corresponding bios are in flight, the only modification will be 786 * set_bit WAS_ERROR, which has to be atomic. 787 * If no bios are in flight yet, or all have been completed, 788 * non-atomic modification to ee->flags is ok. 789 */ 790 enum { 791 __EE_CALL_AL_COMPLETE_IO, 792 __EE_MAY_SET_IN_SYNC, 793 794 /* In case a barrier failed, 795 * we need to resubmit without the barrier flag. */ 796 __EE_RESUBMITTED, 797 798 /* we may have several bios per epoch entry. 799 * if any of those fail, we set this flag atomically 800 * from the endio callback */ 801 __EE_WAS_ERROR, 802 803 /* This ee has a pointer to a digest instead of a block id */ 804 __EE_HAS_DIGEST, 805 }; 806 #define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO) 807 #define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC) 808 #define EE_RESUBMITTED (1<<__EE_RESUBMITTED) 809 #define EE_WAS_ERROR (1<<__EE_WAS_ERROR) 810 #define EE_HAS_DIGEST (1<<__EE_HAS_DIGEST) 811 812 /* global flag bits */ 813 enum { 814 CREATE_BARRIER, /* next P_DATA is preceded by a P_BARRIER */ 815 SIGNAL_ASENDER, /* whether asender wants to be interrupted */ 816 SEND_PING, /* whether asender should send a ping asap */ 817 818 UNPLUG_QUEUED, /* only relevant with kernel 2.4 */ 819 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */ 820 MD_DIRTY, /* current uuids and flags not yet on disk */ 821 DISCARD_CONCURRENT, /* Set on one node, cleared on the peer! */ 822 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */ 823 CLUSTER_ST_CHANGE, /* Cluster wide state change going on... */ 824 CL_ST_CHG_SUCCESS, 825 CL_ST_CHG_FAIL, 826 CRASHED_PRIMARY, /* This node was a crashed primary. 827 * Gets cleared when the state.conn 828 * goes into C_CONNECTED state. */ 829 NO_BARRIER_SUPP, /* underlying block device doesn't implement barriers */ 830 CONSIDER_RESYNC, 831 832 MD_NO_FUA, /* Users wants us to not use FUA/FLUSH on meta data dev */ 833 SUSPEND_IO, /* suspend application io */ 834 BITMAP_IO, /* suspend application io; 835 once no more io in flight, start bitmap io */ 836 BITMAP_IO_QUEUED, /* Started bitmap IO */ 837 GO_DISKLESS, /* Disk is being detached, on io-error or admin request. */ 838 WAS_IO_ERROR, /* Local disk failed returned IO error */ 839 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */ 840 NET_CONGESTED, /* The data socket is congested */ 841 842 CONFIG_PENDING, /* serialization of (re)configuration requests. 843 * if set, also prevents the device from dying */ 844 DEVICE_DYING, /* device became unconfigured, 845 * but worker thread is still handling the cleanup. 846 * reconfiguring (nl_disk_conf, nl_net_conf) is dissalowed, 847 * while this is set. */ 848 RESIZE_PENDING, /* Size change detected locally, waiting for the response from 849 * the peer, if it changed there as well. */ 850 CONN_DRY_RUN, /* Expect disconnect after resync handshake. */ 851 GOT_PING_ACK, /* set when we receive a ping_ack packet, misc wait gets woken */ 852 NEW_CUR_UUID, /* Create new current UUID when thawing IO */ 853 AL_SUSPENDED, /* Activity logging is currently suspended. */ 854 AHEAD_TO_SYNC_SOURCE, /* Ahead -> SyncSource queued */ 855 }; 856 857 struct drbd_bitmap; /* opaque for drbd_conf */ 858 859 /* definition of bits in bm_flags to be used in drbd_bm_lock 860 * and drbd_bitmap_io and friends. */ 861 enum bm_flag { 862 /* do we need to kfree, or vfree bm_pages? */ 863 BM_P_VMALLOCED = 0x10000, /* internal use only, will be masked out */ 864 865 /* currently locked for bulk operation */ 866 BM_LOCKED_MASK = 0x7, 867 868 /* in detail, that is: */ 869 BM_DONT_CLEAR = 0x1, 870 BM_DONT_SET = 0x2, 871 BM_DONT_TEST = 0x4, 872 873 /* (test bit, count bit) allowed (common case) */ 874 BM_LOCKED_TEST_ALLOWED = 0x3, 875 876 /* testing bits, as well as setting new bits allowed, but clearing bits 877 * would be unexpected. Used during bitmap receive. Setting new bits 878 * requires sending of "out-of-sync" information, though. */ 879 BM_LOCKED_SET_ALLOWED = 0x1, 880 881 /* clear is not expected while bitmap is locked for bulk operation */ 882 }; 883 884 885 /* TODO sort members for performance 886 * MAYBE group them further */ 887 888 /* THINK maybe we actually want to use the default "event/%s" worker threads 889 * or similar in linux 2.6, which uses per cpu data and threads. 890 */ 891 struct drbd_work_queue { 892 struct list_head q; 893 struct semaphore s; /* producers up it, worker down()s it */ 894 spinlock_t q_lock; /* to protect the list. */ 895 }; 896 897 struct drbd_socket { 898 struct drbd_work_queue work; 899 struct mutex mutex; 900 struct socket *socket; 901 /* this way we get our 902 * send/receive buffers off the stack */ 903 union p_polymorph sbuf; 904 union p_polymorph rbuf; 905 }; 906 907 struct drbd_md { 908 u64 md_offset; /* sector offset to 'super' block */ 909 910 u64 la_size_sect; /* last agreed size, unit sectors */ 911 u64 uuid[UI_SIZE]; 912 u64 device_uuid; 913 u32 flags; 914 u32 md_size_sect; 915 916 s32 al_offset; /* signed relative sector offset to al area */ 917 s32 bm_offset; /* signed relative sector offset to bitmap */ 918 919 /* u32 al_nr_extents; important for restoring the AL 920 * is stored into sync_conf.al_extents, which in turn 921 * gets applied to act_log->nr_elements 922 */ 923 }; 924 925 /* for sync_conf and other types... */ 926 #define NL_PACKET(name, number, fields) struct name { fields }; 927 #define NL_INTEGER(pn,pr,member) int member; 928 #define NL_INT64(pn,pr,member) __u64 member; 929 #define NL_BIT(pn,pr,member) unsigned member:1; 930 #define NL_STRING(pn,pr,member,len) unsigned char member[len]; int member ## _len; 931 #include "linux/drbd_nl.h" 932 933 struct drbd_backing_dev { 934 struct block_device *backing_bdev; 935 struct block_device *md_bdev; 936 struct drbd_md md; 937 struct disk_conf dc; /* The user provided config... */ 938 sector_t known_size; /* last known size of that backing device */ 939 }; 940 941 struct drbd_md_io { 942 struct drbd_conf *mdev; 943 struct completion event; 944 int error; 945 }; 946 947 struct bm_io_work { 948 struct drbd_work w; 949 char *why; 950 enum bm_flag flags; 951 int (*io_fn)(struct drbd_conf *mdev); 952 void (*done)(struct drbd_conf *mdev, int rv); 953 }; 954 955 enum write_ordering_e { 956 WO_none, 957 WO_drain_io, 958 WO_bdev_flush, 959 }; 960 961 struct fifo_buffer { 962 int *values; 963 unsigned int head_index; 964 unsigned int size; 965 }; 966 967 struct drbd_conf { 968 /* things that are stored as / read from meta data on disk */ 969 unsigned long flags; 970 971 /* configured by drbdsetup */ 972 struct net_conf *net_conf; /* protected by get_net_conf() and put_net_conf() */ 973 struct syncer_conf sync_conf; 974 struct drbd_backing_dev *ldev __protected_by(local); 975 976 sector_t p_size; /* partner's disk size */ 977 struct request_queue *rq_queue; 978 struct block_device *this_bdev; 979 struct gendisk *vdisk; 980 981 struct drbd_socket data; /* data/barrier/cstate/parameter packets */ 982 struct drbd_socket meta; /* ping/ack (metadata) packets */ 983 int agreed_pro_version; /* actually used protocol version */ 984 unsigned long last_received; /* in jiffies, either socket */ 985 unsigned int ko_count; 986 struct drbd_work resync_work, 987 unplug_work, 988 go_diskless, 989 md_sync_work, 990 start_resync_work; 991 struct timer_list resync_timer; 992 struct timer_list md_sync_timer; 993 struct timer_list start_resync_timer; 994 struct timer_list request_timer; 995 #ifdef DRBD_DEBUG_MD_SYNC 996 struct { 997 unsigned int line; 998 const char* func; 999 } last_md_mark_dirty; 1000 #endif 1001 1002 /* Used after attach while negotiating new disk state. */ 1003 union drbd_state new_state_tmp; 1004 1005 union drbd_state state; 1006 wait_queue_head_t misc_wait; 1007 wait_queue_head_t state_wait; /* upon each state change. */ 1008 wait_queue_head_t net_cnt_wait; 1009 unsigned int send_cnt; 1010 unsigned int recv_cnt; 1011 unsigned int read_cnt; 1012 unsigned int writ_cnt; 1013 unsigned int al_writ_cnt; 1014 unsigned int bm_writ_cnt; 1015 atomic_t ap_bio_cnt; /* Requests we need to complete */ 1016 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */ 1017 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */ 1018 atomic_t unacked_cnt; /* Need to send replys for */ 1019 atomic_t local_cnt; /* Waiting for local completion */ 1020 atomic_t net_cnt; /* Users of net_conf */ 1021 spinlock_t req_lock; 1022 struct drbd_tl_epoch *unused_spare_tle; /* for pre-allocation */ 1023 struct drbd_tl_epoch *newest_tle; 1024 struct drbd_tl_epoch *oldest_tle; 1025 struct list_head out_of_sequence_requests; 1026 struct hlist_head *tl_hash; 1027 unsigned int tl_hash_s; 1028 1029 /* blocks to resync in this run [unit BM_BLOCK_SIZE] */ 1030 unsigned long rs_total; 1031 /* number of resync blocks that failed in this run */ 1032 unsigned long rs_failed; 1033 /* Syncer's start time [unit jiffies] */ 1034 unsigned long rs_start; 1035 /* cumulated time in PausedSyncX state [unit jiffies] */ 1036 unsigned long rs_paused; 1037 /* skipped because csum was equal [unit BM_BLOCK_SIZE] */ 1038 unsigned long rs_same_csum; 1039 #define DRBD_SYNC_MARKS 8 1040 #define DRBD_SYNC_MARK_STEP (3*HZ) 1041 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */ 1042 unsigned long rs_mark_left[DRBD_SYNC_MARKS]; 1043 /* marks's time [unit jiffies] */ 1044 unsigned long rs_mark_time[DRBD_SYNC_MARKS]; 1045 /* current index into rs_mark_{left,time} */ 1046 int rs_last_mark; 1047 1048 /* where does the admin want us to start? (sector) */ 1049 sector_t ov_start_sector; 1050 /* where are we now? (sector) */ 1051 sector_t ov_position; 1052 /* Start sector of out of sync range (to merge printk reporting). */ 1053 sector_t ov_last_oos_start; 1054 /* size of out-of-sync range in sectors. */ 1055 sector_t ov_last_oos_size; 1056 unsigned long ov_left; /* in bits */ 1057 struct crypto_hash *csums_tfm; 1058 struct crypto_hash *verify_tfm; 1059 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 mutex md_io_mutex; /* protects the md_io_buffer */ 1099 spinlock_t al_lock; 1100 wait_queue_head_t al_wait; 1101 struct lru_cache *act_log; /* activity log */ 1102 unsigned int al_tr_number; 1103 int al_tr_cycle; 1104 int al_tr_pos; /* position of the next transaction in the journal */ 1105 struct crypto_hash *cram_hmac_tfm; 1106 struct crypto_hash *integrity_w_tfm; /* to be used by the worker thread */ 1107 struct crypto_hash *integrity_r_tfm; /* to be used by the receiver thread */ 1108 void *int_dig_out; 1109 void *int_dig_in; 1110 void *int_dig_vv; 1111 wait_queue_head_t seq_wait; 1112 atomic_t packet_seq; 1113 unsigned int peer_seq; 1114 spinlock_t peer_seq_lock; 1115 unsigned int minor; 1116 unsigned long comm_bm_set; /* communicated number of set bits. */ 1117 cpumask_var_t cpu_mask; 1118 struct bm_io_work bm_io_work; 1119 u64 ed_uuid; /* UUID of the exposed data */ 1120 struct mutex state_mutex; 1121 char congestion_reason; /* Why we where congested... */ 1122 atomic_t rs_sect_in; /* for incoming resync data rate, SyncTarget */ 1123 atomic_t rs_sect_ev; /* for submitted resync data rate, both */ 1124 int rs_last_sect_ev; /* counter to compare with */ 1125 int rs_last_events; /* counter of read or write "events" (unit sectors) 1126 * on the lower level device when we last looked. */ 1127 int c_sync_rate; /* current resync rate after syncer throttle magic */ 1128 struct fifo_buffer rs_plan_s; /* correction values of resync planer */ 1129 int rs_in_flight; /* resync sectors in flight (to proxy, in proxy and from proxy) */ 1130 int rs_planed; /* resync sectors already planned */ 1131 atomic_t ap_in_flight; /* App sectors in flight (waiting for ack) */ 1132 int peer_max_bio_size; 1133 int local_max_bio_size; 1134 }; 1135 1136 static inline struct drbd_conf *minor_to_mdev(unsigned int minor) 1137 { 1138 struct drbd_conf *mdev; 1139 1140 mdev = minor < minor_count ? minor_table[minor] : NULL; 1141 1142 return mdev; 1143 } 1144 1145 static inline unsigned int mdev_to_minor(struct drbd_conf *mdev) 1146 { 1147 return mdev->minor; 1148 } 1149 1150 /* returns 1 if it was successful, 1151 * returns 0 if there was no data socket. 1152 * so wherever you are going to use the data.socket, e.g. do 1153 * if (!drbd_get_data_sock(mdev)) 1154 * return 0; 1155 * CODE(); 1156 * drbd_put_data_sock(mdev); 1157 */ 1158 static inline int drbd_get_data_sock(struct drbd_conf *mdev) 1159 { 1160 mutex_lock(&mdev->data.mutex); 1161 /* drbd_disconnect() could have called drbd_free_sock() 1162 * while we were waiting in down()... */ 1163 if (unlikely(mdev->data.socket == NULL)) { 1164 mutex_unlock(&mdev->data.mutex); 1165 return 0; 1166 } 1167 return 1; 1168 } 1169 1170 static inline void drbd_put_data_sock(struct drbd_conf *mdev) 1171 { 1172 mutex_unlock(&mdev->data.mutex); 1173 } 1174 1175 /* 1176 * function declarations 1177 *************************/ 1178 1179 /* drbd_main.c */ 1180 1181 enum chg_state_flags { 1182 CS_HARD = 1, 1183 CS_VERBOSE = 2, 1184 CS_WAIT_COMPLETE = 4, 1185 CS_SERIALIZE = 8, 1186 CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE, 1187 }; 1188 1189 enum dds_flags { 1190 DDSF_FORCED = 1, 1191 DDSF_NO_RESYNC = 2, /* Do not run a resync for the new space */ 1192 }; 1193 1194 extern void drbd_init_set_defaults(struct drbd_conf *mdev); 1195 extern enum drbd_state_rv drbd_change_state(struct drbd_conf *mdev, 1196 enum chg_state_flags f, 1197 union drbd_state mask, 1198 union drbd_state val); 1199 extern void drbd_force_state(struct drbd_conf *, union drbd_state, 1200 union drbd_state); 1201 extern enum drbd_state_rv _drbd_request_state(struct drbd_conf *, 1202 union drbd_state, 1203 union drbd_state, 1204 enum chg_state_flags); 1205 extern enum drbd_state_rv __drbd_set_state(struct drbd_conf *, union drbd_state, 1206 enum chg_state_flags, 1207 struct completion *done); 1208 extern void print_st_err(struct drbd_conf *, union drbd_state, 1209 union drbd_state, int); 1210 extern int drbd_thread_start(struct drbd_thread *thi); 1211 extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait); 1212 #ifdef CONFIG_SMP 1213 extern void drbd_thread_current_set_cpu(struct drbd_conf *mdev); 1214 extern void drbd_calc_cpu_mask(struct drbd_conf *mdev); 1215 #else 1216 #define drbd_thread_current_set_cpu(A) ({}) 1217 #define drbd_calc_cpu_mask(A) ({}) 1218 #endif 1219 extern void drbd_free_resources(struct drbd_conf *mdev); 1220 extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr, 1221 unsigned int set_size); 1222 extern void tl_clear(struct drbd_conf *mdev); 1223 extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *); 1224 extern void drbd_free_sock(struct drbd_conf *mdev); 1225 extern int drbd_send(struct drbd_conf *mdev, struct socket *sock, 1226 void *buf, size_t size, unsigned msg_flags); 1227 extern int drbd_send_protocol(struct drbd_conf *mdev); 1228 extern int drbd_send_uuids(struct drbd_conf *mdev); 1229 extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev); 1230 extern int drbd_gen_and_send_sync_uuid(struct drbd_conf *mdev); 1231 extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags); 1232 extern int _drbd_send_state(struct drbd_conf *mdev); 1233 extern int drbd_send_state(struct drbd_conf *mdev); 1234 extern int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock, 1235 enum drbd_packets cmd, struct p_header80 *h, 1236 size_t size, unsigned msg_flags); 1237 #define USE_DATA_SOCKET 1 1238 #define USE_META_SOCKET 0 1239 extern int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket, 1240 enum drbd_packets cmd, struct p_header80 *h, 1241 size_t size); 1242 extern int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, 1243 char *data, size_t size); 1244 extern int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc); 1245 extern int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, 1246 u32 set_size); 1247 extern int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd, 1248 struct drbd_epoch_entry *e); 1249 extern int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd, 1250 struct p_block_req *rp); 1251 extern int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd, 1252 struct p_data *dp, int data_size); 1253 extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd, 1254 sector_t sector, int blksize, u64 block_id); 1255 extern int drbd_send_oos(struct drbd_conf *mdev, struct drbd_request *req); 1256 extern int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd, 1257 struct drbd_epoch_entry *e); 1258 extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req); 1259 extern int drbd_send_drequest(struct drbd_conf *mdev, int cmd, 1260 sector_t sector, int size, u64 block_id); 1261 extern int drbd_send_drequest_csum(struct drbd_conf *mdev, 1262 sector_t sector,int size, 1263 void *digest, int digest_size, 1264 enum drbd_packets cmd); 1265 extern int drbd_send_ov_request(struct drbd_conf *mdev,sector_t sector,int size); 1266 1267 extern int drbd_send_bitmap(struct drbd_conf *mdev); 1268 extern int _drbd_send_bitmap(struct drbd_conf *mdev); 1269 extern int drbd_send_sr_reply(struct drbd_conf *mdev, enum drbd_state_rv retcode); 1270 extern void drbd_free_bc(struct drbd_backing_dev *ldev); 1271 extern void drbd_mdev_cleanup(struct drbd_conf *mdev); 1272 void drbd_print_uuids(struct drbd_conf *mdev, const char *text); 1273 1274 extern void drbd_md_sync(struct drbd_conf *mdev); 1275 extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev); 1276 extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1277 extern void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local); 1278 extern void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1279 extern void _drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local); 1280 extern void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local); 1281 extern void drbd_md_set_flag(struct drbd_conf *mdev, int flags) __must_hold(local); 1282 extern void drbd_md_clear_flag(struct drbd_conf *mdev, int flags)__must_hold(local); 1283 extern int drbd_md_test_flag(struct drbd_backing_dev *, int); 1284 #ifndef DRBD_DEBUG_MD_SYNC 1285 extern void drbd_md_mark_dirty(struct drbd_conf *mdev); 1286 #else 1287 #define drbd_md_mark_dirty(m) drbd_md_mark_dirty_(m, __LINE__ , __func__ ) 1288 extern void drbd_md_mark_dirty_(struct drbd_conf *mdev, 1289 unsigned int line, const char *func); 1290 #endif 1291 extern void drbd_queue_bitmap_io(struct drbd_conf *mdev, 1292 int (*io_fn)(struct drbd_conf *), 1293 void (*done)(struct drbd_conf *, int), 1294 char *why, enum bm_flag flags); 1295 extern int drbd_bitmap_io(struct drbd_conf *mdev, 1296 int (*io_fn)(struct drbd_conf *), 1297 char *why, enum bm_flag flags); 1298 extern int drbd_bmio_set_n_write(struct drbd_conf *mdev); 1299 extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev); 1300 extern void drbd_go_diskless(struct drbd_conf *mdev); 1301 extern void drbd_ldev_destroy(struct drbd_conf *mdev); 1302 1303 1304 /* Meta data layout 1305 We reserve a 128MB Block (4k aligned) 1306 * either at the end of the backing device 1307 * or on a separate meta data device. */ 1308 1309 #define MD_RESERVED_SECT (128LU << 11) /* 128 MB, unit sectors */ 1310 /* The following numbers are sectors */ 1311 #define MD_AL_OFFSET 8 /* 8 Sectors after start of meta area */ 1312 #define MD_AL_MAX_SIZE 64 /* = 32 kb LOG ~ 3776 extents ~ 14 GB Storage */ 1313 /* Allows up to about 3.8TB */ 1314 #define MD_BM_OFFSET (MD_AL_OFFSET + MD_AL_MAX_SIZE) 1315 1316 /* Since the smalles IO unit is usually 512 byte */ 1317 #define MD_SECTOR_SHIFT 9 1318 #define MD_SECTOR_SIZE (1<<MD_SECTOR_SHIFT) 1319 1320 /* activity log */ 1321 #define AL_EXTENTS_PT ((MD_SECTOR_SIZE-12)/8-1) /* 61 ; Extents per 512B sector */ 1322 #define AL_EXTENT_SHIFT 22 /* One extent represents 4M Storage */ 1323 #define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT) 1324 1325 #if BITS_PER_LONG == 32 1326 #define LN2_BPL 5 1327 #define cpu_to_lel(A) cpu_to_le32(A) 1328 #define lel_to_cpu(A) le32_to_cpu(A) 1329 #elif BITS_PER_LONG == 64 1330 #define LN2_BPL 6 1331 #define cpu_to_lel(A) cpu_to_le64(A) 1332 #define lel_to_cpu(A) le64_to_cpu(A) 1333 #else 1334 #error "LN2 of BITS_PER_LONG unknown!" 1335 #endif 1336 1337 /* resync bitmap */ 1338 /* 16MB sized 'bitmap extent' to track syncer usage */ 1339 struct bm_extent { 1340 int rs_left; /* number of bits set (out of sync) in this extent. */ 1341 int rs_failed; /* number of failed resync requests in this extent. */ 1342 unsigned long flags; 1343 struct lc_element lce; 1344 }; 1345 1346 #define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */ 1347 #define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */ 1348 #define BME_PRIORITY 2 /* finish resync IO on this extent ASAP! App IO waiting! */ 1349 1350 /* drbd_bitmap.c */ 1351 /* 1352 * We need to store one bit for a block. 1353 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap. 1354 * Bit 0 ==> local node thinks this block is binary identical on both nodes 1355 * Bit 1 ==> local node thinks this block needs to be synced. 1356 */ 1357 1358 #define SLEEP_TIME (HZ/10) 1359 1360 #define BM_BLOCK_SHIFT 12 /* 4k per bit */ 1361 #define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT) 1362 /* (9+3) : 512 bytes @ 8 bits; representing 16M storage 1363 * per sector of on disk bitmap */ 1364 #define BM_EXT_SHIFT (BM_BLOCK_SHIFT + MD_SECTOR_SHIFT + 3) /* = 24 */ 1365 #define BM_EXT_SIZE (1<<BM_EXT_SHIFT) 1366 1367 #if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12) 1368 #error "HAVE YOU FIXED drbdmeta AS WELL??" 1369 #endif 1370 1371 /* thus many _storage_ sectors are described by one bit */ 1372 #define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9)) 1373 #define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9)) 1374 #define BM_SECT_PER_BIT BM_BIT_TO_SECT(1) 1375 1376 /* bit to represented kilo byte conversion */ 1377 #define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10)) 1378 1379 /* in which _bitmap_ extent (resp. sector) the bit for a certain 1380 * _storage_ sector is located in */ 1381 #define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9)) 1382 1383 /* how much _storage_ sectors we have per bitmap sector */ 1384 #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9)) 1385 #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1) 1386 1387 /* in one sector of the bitmap, we have this many activity_log extents. */ 1388 #define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT)) 1389 #define BM_WORDS_PER_AL_EXT (1 << (AL_EXTENT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL)) 1390 1391 #define BM_BLOCKS_PER_BM_EXT_B (BM_EXT_SHIFT - BM_BLOCK_SHIFT) 1392 #define BM_BLOCKS_PER_BM_EXT_MASK ((1<<BM_BLOCKS_PER_BM_EXT_B) - 1) 1393 1394 /* the extent in "PER_EXTENT" below is an activity log extent 1395 * we need that many (long words/bytes) to store the bitmap 1396 * of one AL_EXTENT_SIZE chunk of storage. 1397 * we can store the bitmap for that many AL_EXTENTS within 1398 * one sector of the _on_disk_ bitmap: 1399 * bit 0 bit 37 bit 38 bit (512*8)-1 1400 * ...|........|........|.. // ..|........| 1401 * sect. 0 `296 `304 ^(512*8*8)-1 1402 * 1403 #define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG ) 1404 #define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128 1405 #define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4 1406 */ 1407 1408 #define DRBD_MAX_SECTORS_32 (0xffffffffLU) 1409 #define DRBD_MAX_SECTORS_BM \ 1410 ((MD_RESERVED_SECT - MD_BM_OFFSET) * (1LL<<(BM_EXT_SHIFT-9))) 1411 #if DRBD_MAX_SECTORS_BM < DRBD_MAX_SECTORS_32 1412 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1413 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_BM 1414 #elif !defined(CONFIG_LBDAF) && BITS_PER_LONG == 32 1415 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_32 1416 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_32 1417 #else 1418 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM 1419 /* 16 TB in units of sectors */ 1420 #if BITS_PER_LONG == 32 1421 /* adjust by one page worth of bitmap, 1422 * so we won't wrap around in drbd_bm_find_next_bit. 1423 * you should use 64bit OS for that much storage, anyways. */ 1424 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff) 1425 #else 1426 /* we allow up to 1 PiB now on 64bit architecture with "flexible" meta data */ 1427 #define DRBD_MAX_SECTORS_FLEX (1UL << 51) 1428 /* corresponds to (1UL << 38) bits right now. */ 1429 #endif 1430 #endif 1431 1432 /* Sector shift value for the "hash" functions of tl_hash and ee_hash tables. 1433 * With a value of 8 all IO in one 128K block make it to the same slot of the 1434 * hash table. */ 1435 #define HT_SHIFT 8 1436 #define DRBD_MAX_BIO_SIZE (1U<<(9+HT_SHIFT)) 1437 #define DRBD_MAX_BIO_SIZE_SAFE (1 << 12) /* Works always = 4k */ 1438 1439 #define DRBD_MAX_SIZE_H80_PACKET (1 << 15) /* The old header only allows packets up to 32Kib data */ 1440 1441 /* Number of elements in the app_reads_hash */ 1442 #define APP_R_HSIZE 15 1443 1444 extern int drbd_bm_init(struct drbd_conf *mdev); 1445 extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors, int set_new_bits); 1446 extern void drbd_bm_cleanup(struct drbd_conf *mdev); 1447 extern void drbd_bm_set_all(struct drbd_conf *mdev); 1448 extern void drbd_bm_clear_all(struct drbd_conf *mdev); 1449 /* set/clear/test only a few bits at a time */ 1450 extern int drbd_bm_set_bits( 1451 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1452 extern int drbd_bm_clear_bits( 1453 struct drbd_conf *mdev, unsigned long s, unsigned long e); 1454 extern int drbd_bm_count_bits( 1455 struct drbd_conf *mdev, const unsigned long s, const unsigned long e); 1456 /* bm_set_bits variant for use while holding drbd_bm_lock, 1457 * may process the whole bitmap in one go */ 1458 extern void _drbd_bm_set_bits(struct drbd_conf *mdev, 1459 const unsigned long s, const unsigned long e); 1460 extern int drbd_bm_test_bit(struct drbd_conf *mdev, unsigned long bitnr); 1461 extern int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr); 1462 extern int drbd_bm_write_page(struct drbd_conf *mdev, unsigned int idx) __must_hold(local); 1463 extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local); 1464 extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local); 1465 extern unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev, 1466 unsigned long al_enr); 1467 extern size_t drbd_bm_words(struct drbd_conf *mdev); 1468 extern unsigned long drbd_bm_bits(struct drbd_conf *mdev); 1469 extern sector_t drbd_bm_capacity(struct drbd_conf *mdev); 1470 1471 #define DRBD_END_OF_BITMAP (~(unsigned long)0) 1472 extern unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1473 /* bm_find_next variants for use while you hold drbd_bm_lock() */ 1474 extern unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo); 1475 extern unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo); 1476 extern unsigned long _drbd_bm_total_weight(struct drbd_conf *mdev); 1477 extern unsigned long drbd_bm_total_weight(struct drbd_conf *mdev); 1478 extern int drbd_bm_rs_done(struct drbd_conf *mdev); 1479 /* for receive_bitmap */ 1480 extern void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset, 1481 size_t number, unsigned long *buffer); 1482 /* for _drbd_send_bitmap */ 1483 extern void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset, 1484 size_t number, unsigned long *buffer); 1485 1486 extern void drbd_bm_lock(struct drbd_conf *mdev, char *why, enum bm_flag flags); 1487 extern void drbd_bm_unlock(struct drbd_conf *mdev); 1488 /* drbd_main.c */ 1489 1490 extern struct kmem_cache *drbd_request_cache; 1491 extern struct kmem_cache *drbd_ee_cache; /* epoch entries */ 1492 extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ 1493 extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ 1494 extern mempool_t *drbd_request_mempool; 1495 extern mempool_t *drbd_ee_mempool; 1496 1497 extern struct page *drbd_pp_pool; /* drbd's page pool */ 1498 extern spinlock_t drbd_pp_lock; 1499 extern int drbd_pp_vacant; 1500 extern wait_queue_head_t drbd_pp_wait; 1501 1502 extern rwlock_t global_state_lock; 1503 1504 extern struct drbd_conf *drbd_new_device(unsigned int minor); 1505 extern void drbd_free_mdev(struct drbd_conf *mdev); 1506 1507 extern int proc_details; 1508 1509 /* drbd_req */ 1510 extern int drbd_make_request(struct request_queue *q, struct bio *bio); 1511 extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req); 1512 extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec); 1513 extern int is_valid_ar_handle(struct drbd_request *, sector_t); 1514 1515 1516 /* drbd_nl.c */ 1517 extern void drbd_suspend_io(struct drbd_conf *mdev); 1518 extern void drbd_resume_io(struct drbd_conf *mdev); 1519 extern char *ppsize(char *buf, unsigned long long size); 1520 extern sector_t drbd_new_dev_size(struct drbd_conf *, struct drbd_backing_dev *, int); 1521 enum determine_dev_size { dev_size_error = -1, unchanged = 0, shrunk = 1, grew = 2 }; 1522 extern enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *, enum dds_flags) __must_hold(local); 1523 extern void resync_after_online_grow(struct drbd_conf *); 1524 extern void drbd_reconsider_max_bio_size(struct drbd_conf *mdev); 1525 extern enum drbd_state_rv drbd_set_role(struct drbd_conf *mdev, 1526 enum drbd_role new_role, 1527 int force); 1528 extern enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev); 1529 extern void drbd_try_outdate_peer_async(struct drbd_conf *mdev); 1530 extern int drbd_khelper(struct drbd_conf *mdev, char *cmd); 1531 1532 /* drbd_worker.c */ 1533 extern int drbd_worker(struct drbd_thread *thi); 1534 extern int drbd_alter_sa(struct drbd_conf *mdev, int na); 1535 extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side); 1536 extern void resume_next_sg(struct drbd_conf *mdev); 1537 extern void suspend_other_sg(struct drbd_conf *mdev); 1538 extern int drbd_resync_finished(struct drbd_conf *mdev); 1539 /* maybe rather drbd_main.c ? */ 1540 extern int drbd_md_sync_page_io(struct drbd_conf *mdev, 1541 struct drbd_backing_dev *bdev, sector_t sector, int rw); 1542 extern void drbd_ov_oos_found(struct drbd_conf*, sector_t, int); 1543 extern void drbd_rs_controller_reset(struct drbd_conf *mdev); 1544 1545 static inline void ov_oos_print(struct drbd_conf *mdev) 1546 { 1547 if (mdev->ov_last_oos_size) { 1548 dev_err(DEV, "Out of sync: start=%llu, size=%lu (sectors)\n", 1549 (unsigned long long)mdev->ov_last_oos_start, 1550 (unsigned long)mdev->ov_last_oos_size); 1551 } 1552 mdev->ov_last_oos_size=0; 1553 } 1554 1555 1556 extern void drbd_csum_bio(struct drbd_conf *, struct crypto_hash *, struct bio *, void *); 1557 extern void drbd_csum_ee(struct drbd_conf *, struct crypto_hash *, struct drbd_epoch_entry *, void *); 1558 /* worker callbacks */ 1559 extern int w_req_cancel_conflict(struct drbd_conf *, struct drbd_work *, int); 1560 extern int w_read_retry_remote(struct drbd_conf *, struct drbd_work *, int); 1561 extern int w_e_end_data_req(struct drbd_conf *, struct drbd_work *, int); 1562 extern int w_e_end_rsdata_req(struct drbd_conf *, struct drbd_work *, int); 1563 extern int w_e_end_csum_rs_req(struct drbd_conf *, struct drbd_work *, int); 1564 extern int w_e_end_ov_reply(struct drbd_conf *, struct drbd_work *, int); 1565 extern int w_e_end_ov_req(struct drbd_conf *, struct drbd_work *, int); 1566 extern int w_ov_finished(struct drbd_conf *, struct drbd_work *, int); 1567 extern int w_resync_timer(struct drbd_conf *, struct drbd_work *, int); 1568 extern int w_resume_next_sg(struct drbd_conf *, struct drbd_work *, int); 1569 extern int w_send_write_hint(struct drbd_conf *, struct drbd_work *, int); 1570 extern int w_send_dblock(struct drbd_conf *, struct drbd_work *, int); 1571 extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int); 1572 extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int); 1573 extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int); 1574 extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int); 1575 extern int w_restart_disk_io(struct drbd_conf *, struct drbd_work *, int); 1576 extern int w_send_oos(struct drbd_conf *, struct drbd_work *, int); 1577 extern int w_start_resync(struct drbd_conf *, struct drbd_work *, int); 1578 1579 extern void resync_timer_fn(unsigned long data); 1580 extern void start_resync_timer_fn(unsigned long data); 1581 1582 /* drbd_receiver.c */ 1583 extern int drbd_rs_should_slow_down(struct drbd_conf *mdev, sector_t sector); 1584 extern int drbd_submit_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, 1585 const unsigned rw, const int fault_type); 1586 extern int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list); 1587 extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev, 1588 u64 id, 1589 sector_t sector, 1590 unsigned int data_size, 1591 gfp_t gfp_mask) __must_hold(local); 1592 extern void drbd_free_some_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, 1593 int is_net); 1594 #define drbd_free_ee(m,e) drbd_free_some_ee(m, e, 0) 1595 #define drbd_free_net_ee(m,e) drbd_free_some_ee(m, e, 1) 1596 extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1597 struct list_head *head); 1598 extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev, 1599 struct list_head *head); 1600 extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled); 1601 extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed); 1602 extern void drbd_flush_workqueue(struct drbd_conf *mdev); 1603 extern void drbd_free_tl_hash(struct drbd_conf *mdev); 1604 1605 /* yes, there is kernel_setsockopt, but only since 2.6.18. we don't need to 1606 * mess with get_fs/set_fs, we know we are KERNEL_DS always. */ 1607 static inline int drbd_setsockopt(struct socket *sock, int level, int optname, 1608 char __user *optval, int optlen) 1609 { 1610 int err; 1611 if (level == SOL_SOCKET) 1612 err = sock_setsockopt(sock, level, optname, optval, optlen); 1613 else 1614 err = sock->ops->setsockopt(sock, level, optname, optval, 1615 optlen); 1616 return err; 1617 } 1618 1619 static inline void drbd_tcp_cork(struct socket *sock) 1620 { 1621 int __user val = 1; 1622 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1623 (char __user *)&val, sizeof(val)); 1624 } 1625 1626 static inline void drbd_tcp_uncork(struct socket *sock) 1627 { 1628 int __user val = 0; 1629 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK, 1630 (char __user *)&val, sizeof(val)); 1631 } 1632 1633 static inline void drbd_tcp_nodelay(struct socket *sock) 1634 { 1635 int __user val = 1; 1636 (void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY, 1637 (char __user *)&val, sizeof(val)); 1638 } 1639 1640 static inline void drbd_tcp_quickack(struct socket *sock) 1641 { 1642 int __user val = 2; 1643 (void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK, 1644 (char __user *)&val, sizeof(val)); 1645 } 1646 1647 void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo); 1648 1649 /* drbd_proc.c */ 1650 extern struct proc_dir_entry *drbd_proc; 1651 extern const struct file_operations drbd_proc_fops; 1652 extern const char *drbd_conn_str(enum drbd_conns s); 1653 extern const char *drbd_role_str(enum drbd_role s); 1654 1655 /* drbd_actlog.c */ 1656 extern void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector); 1657 extern void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector); 1658 extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector); 1659 extern int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1660 extern int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector); 1661 extern void drbd_rs_cancel_all(struct drbd_conf *mdev); 1662 extern int drbd_rs_del_all(struct drbd_conf *mdev); 1663 extern void drbd_rs_failed_io(struct drbd_conf *mdev, 1664 sector_t sector, int size); 1665 extern int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *); 1666 extern void drbd_advance_rs_marks(struct drbd_conf *mdev, unsigned long still_to_go); 1667 extern void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector, 1668 int size, const char *file, const unsigned int line); 1669 #define drbd_set_in_sync(mdev, sector, size) \ 1670 __drbd_set_in_sync(mdev, sector, size, __FILE__, __LINE__) 1671 extern int __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector, 1672 int size, const char *file, const unsigned int line); 1673 #define drbd_set_out_of_sync(mdev, sector, size) \ 1674 __drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__) 1675 extern void drbd_al_apply_to_bm(struct drbd_conf *mdev); 1676 extern void drbd_al_shrink(struct drbd_conf *mdev); 1677 1678 1679 /* drbd_nl.c */ 1680 1681 void drbd_nl_cleanup(void); 1682 int __init drbd_nl_init(void); 1683 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state); 1684 void drbd_bcast_sync_progress(struct drbd_conf *mdev); 1685 void drbd_bcast_ee(struct drbd_conf *mdev, 1686 const char *reason, const int dgs, 1687 const char* seen_hash, const char* calc_hash, 1688 const struct drbd_epoch_entry* e); 1689 1690 1691 /** 1692 * DOC: DRBD State macros 1693 * 1694 * These macros are used to express state changes in easily readable form. 1695 * 1696 * The NS macros expand to a mask and a value, that can be bit ored onto the 1697 * current state as soon as the spinlock (req_lock) was taken. 1698 * 1699 * The _NS macros are used for state functions that get called with the 1700 * spinlock. These macros expand directly to the new state value. 1701 * 1702 * Besides the basic forms NS() and _NS() additional _?NS[23] are defined 1703 * to express state changes that affect more than one aspect of the state. 1704 * 1705 * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY) 1706 * Means that the network connection was established and that the peer 1707 * is in secondary role. 1708 */ 1709 #define role_MASK R_MASK 1710 #define peer_MASK R_MASK 1711 #define disk_MASK D_MASK 1712 #define pdsk_MASK D_MASK 1713 #define conn_MASK C_MASK 1714 #define susp_MASK 1 1715 #define user_isp_MASK 1 1716 #define aftr_isp_MASK 1 1717 #define susp_nod_MASK 1 1718 #define susp_fen_MASK 1 1719 1720 #define NS(T, S) \ 1721 ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \ 1722 ({ union drbd_state val; val.i = 0; val.T = (S); val; }) 1723 #define NS2(T1, S1, T2, S2) \ 1724 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1725 mask.T2 = T2##_MASK; mask; }), \ 1726 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1727 val.T2 = (S2); val; }) 1728 #define NS3(T1, S1, T2, S2, T3, S3) \ 1729 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \ 1730 mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \ 1731 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \ 1732 val.T2 = (S2); val.T3 = (S3); val; }) 1733 1734 #define _NS(D, T, S) \ 1735 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; }) 1736 #define _NS2(D, T1, S1, T2, S2) \ 1737 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1738 __ns.T2 = (S2); __ns; }) 1739 #define _NS3(D, T1, S1, T2, S2, T3, S3) \ 1740 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \ 1741 __ns.T2 = (S2); __ns.T3 = (S3); __ns; }) 1742 1743 /* 1744 * inline helper functions 1745 *************************/ 1746 1747 /* see also page_chain_add and friends in drbd_receiver.c */ 1748 static inline struct page *page_chain_next(struct page *page) 1749 { 1750 return (struct page *)page_private(page); 1751 } 1752 #define page_chain_for_each(page) \ 1753 for (; page && ({ prefetch(page_chain_next(page)); 1; }); \ 1754 page = page_chain_next(page)) 1755 #define page_chain_for_each_safe(page, n) \ 1756 for (; page && ({ n = page_chain_next(page); 1; }); page = n) 1757 1758 static inline int drbd_bio_has_active_page(struct bio *bio) 1759 { 1760 struct bio_vec *bvec; 1761 int i; 1762 1763 __bio_for_each_segment(bvec, bio, i, 0) { 1764 if (page_count(bvec->bv_page) > 1) 1765 return 1; 1766 } 1767 1768 return 0; 1769 } 1770 1771 static inline int drbd_ee_has_active_page(struct drbd_epoch_entry *e) 1772 { 1773 struct page *page = e->pages; 1774 page_chain_for_each(page) { 1775 if (page_count(page) > 1) 1776 return 1; 1777 } 1778 return 0; 1779 } 1780 1781 1782 static inline void drbd_state_lock(struct drbd_conf *mdev) 1783 { 1784 wait_event(mdev->misc_wait, 1785 !test_and_set_bit(CLUSTER_ST_CHANGE, &mdev->flags)); 1786 } 1787 1788 static inline void drbd_state_unlock(struct drbd_conf *mdev) 1789 { 1790 clear_bit(CLUSTER_ST_CHANGE, &mdev->flags); 1791 wake_up(&mdev->misc_wait); 1792 } 1793 1794 static inline enum drbd_state_rv 1795 _drbd_set_state(struct drbd_conf *mdev, union drbd_state ns, 1796 enum chg_state_flags flags, struct completion *done) 1797 { 1798 enum drbd_state_rv rv; 1799 1800 read_lock(&global_state_lock); 1801 rv = __drbd_set_state(mdev, ns, flags, done); 1802 read_unlock(&global_state_lock); 1803 1804 return rv; 1805 } 1806 1807 /** 1808 * drbd_request_state() - Reqest a state change 1809 * @mdev: DRBD device. 1810 * @mask: mask of state bits to change. 1811 * @val: value of new state bits. 1812 * 1813 * This is the most graceful way of requesting a state change. It is verbose 1814 * quite verbose in case the state change is not possible, and all those 1815 * state changes are globally serialized. 1816 */ 1817 static inline int drbd_request_state(struct drbd_conf *mdev, 1818 union drbd_state mask, 1819 union drbd_state val) 1820 { 1821 return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED); 1822 } 1823 1824 #define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__) 1825 static inline void __drbd_chk_io_error_(struct drbd_conf *mdev, int forcedetach, const char *where) 1826 { 1827 switch (mdev->ldev->dc.on_io_error) { 1828 case EP_PASS_ON: 1829 if (!forcedetach) { 1830 if (__ratelimit(&drbd_ratelimit_state)) 1831 dev_err(DEV, "Local IO failed in %s.\n", where); 1832 if (mdev->state.disk > D_INCONSISTENT) 1833 _drbd_set_state(_NS(mdev, disk, D_INCONSISTENT), CS_HARD, NULL); 1834 break; 1835 } 1836 /* NOTE fall through to detach case if forcedetach set */ 1837 case EP_DETACH: 1838 case EP_CALL_HELPER: 1839 set_bit(WAS_IO_ERROR, &mdev->flags); 1840 if (mdev->state.disk > D_FAILED) { 1841 _drbd_set_state(_NS(mdev, disk, D_FAILED), CS_HARD, NULL); 1842 dev_err(DEV, 1843 "Local IO failed in %s. Detaching...\n", where); 1844 } 1845 break; 1846 } 1847 } 1848 1849 /** 1850 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers 1851 * @mdev: DRBD device. 1852 * @error: Error code passed to the IO completion callback 1853 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data 1854 * 1855 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED) 1856 */ 1857 #define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__) 1858 static inline void drbd_chk_io_error_(struct drbd_conf *mdev, 1859 int error, int forcedetach, const char *where) 1860 { 1861 if (error) { 1862 unsigned long flags; 1863 spin_lock_irqsave(&mdev->req_lock, flags); 1864 __drbd_chk_io_error_(mdev, forcedetach, where); 1865 spin_unlock_irqrestore(&mdev->req_lock, flags); 1866 } 1867 } 1868 1869 1870 /** 1871 * drbd_md_first_sector() - Returns the first sector number of the meta data area 1872 * @bdev: Meta data block device. 1873 * 1874 * BTW, for internal meta data, this happens to be the maximum capacity 1875 * we could agree upon with our peer node. 1876 */ 1877 static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev) 1878 { 1879 switch (bdev->dc.meta_dev_idx) { 1880 case DRBD_MD_INDEX_INTERNAL: 1881 case DRBD_MD_INDEX_FLEX_INT: 1882 return bdev->md.md_offset + bdev->md.bm_offset; 1883 case DRBD_MD_INDEX_FLEX_EXT: 1884 default: 1885 return bdev->md.md_offset; 1886 } 1887 } 1888 1889 /** 1890 * drbd_md_last_sector() - Return the last sector number of the meta data area 1891 * @bdev: Meta data block device. 1892 */ 1893 static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev) 1894 { 1895 switch (bdev->dc.meta_dev_idx) { 1896 case DRBD_MD_INDEX_INTERNAL: 1897 case DRBD_MD_INDEX_FLEX_INT: 1898 return bdev->md.md_offset + MD_AL_OFFSET - 1; 1899 case DRBD_MD_INDEX_FLEX_EXT: 1900 default: 1901 return bdev->md.md_offset + bdev->md.md_size_sect; 1902 } 1903 } 1904 1905 /* Returns the number of 512 byte sectors of the device */ 1906 static inline sector_t drbd_get_capacity(struct block_device *bdev) 1907 { 1908 /* return bdev ? get_capacity(bdev->bd_disk) : 0; */ 1909 return bdev ? i_size_read(bdev->bd_inode) >> 9 : 0; 1910 } 1911 1912 /** 1913 * drbd_get_max_capacity() - Returns the capacity we announce to out peer 1914 * @bdev: Meta data block device. 1915 * 1916 * returns the capacity we announce to out peer. we clip ourselves at the 1917 * various MAX_SECTORS, because if we don't, current implementation will 1918 * oops sooner or later 1919 */ 1920 static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev) 1921 { 1922 sector_t s; 1923 switch (bdev->dc.meta_dev_idx) { 1924 case DRBD_MD_INDEX_INTERNAL: 1925 case DRBD_MD_INDEX_FLEX_INT: 1926 s = drbd_get_capacity(bdev->backing_bdev) 1927 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1928 drbd_md_first_sector(bdev)) 1929 : 0; 1930 break; 1931 case DRBD_MD_INDEX_FLEX_EXT: 1932 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX, 1933 drbd_get_capacity(bdev->backing_bdev)); 1934 /* clip at maximum size the meta device can support */ 1935 s = min_t(sector_t, s, 1936 BM_EXT_TO_SECT(bdev->md.md_size_sect 1937 - bdev->md.bm_offset)); 1938 break; 1939 default: 1940 s = min_t(sector_t, DRBD_MAX_SECTORS, 1941 drbd_get_capacity(bdev->backing_bdev)); 1942 } 1943 return s; 1944 } 1945 1946 /** 1947 * drbd_md_ss__() - Return the sector number of our meta data super block 1948 * @mdev: DRBD device. 1949 * @bdev: Meta data block device. 1950 */ 1951 static inline sector_t drbd_md_ss__(struct drbd_conf *mdev, 1952 struct drbd_backing_dev *bdev) 1953 { 1954 switch (bdev->dc.meta_dev_idx) { 1955 default: /* external, some index */ 1956 return MD_RESERVED_SECT * bdev->dc.meta_dev_idx; 1957 case DRBD_MD_INDEX_INTERNAL: 1958 /* with drbd08, internal meta data is always "flexible" */ 1959 case DRBD_MD_INDEX_FLEX_INT: 1960 /* sizeof(struct md_on_disk_07) == 4k 1961 * position: last 4k aligned block of 4k size */ 1962 if (!bdev->backing_bdev) { 1963 if (__ratelimit(&drbd_ratelimit_state)) { 1964 dev_err(DEV, "bdev->backing_bdev==NULL\n"); 1965 dump_stack(); 1966 } 1967 return 0; 1968 } 1969 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL) 1970 - MD_AL_OFFSET; 1971 case DRBD_MD_INDEX_FLEX_EXT: 1972 return 0; 1973 } 1974 } 1975 1976 static inline void 1977 drbd_queue_work_front(struct drbd_work_queue *q, struct drbd_work *w) 1978 { 1979 unsigned long flags; 1980 spin_lock_irqsave(&q->q_lock, flags); 1981 list_add(&w->list, &q->q); 1982 up(&q->s); /* within the spinlock, 1983 see comment near end of drbd_worker() */ 1984 spin_unlock_irqrestore(&q->q_lock, flags); 1985 } 1986 1987 static inline void 1988 drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w) 1989 { 1990 unsigned long flags; 1991 spin_lock_irqsave(&q->q_lock, flags); 1992 list_add_tail(&w->list, &q->q); 1993 up(&q->s); /* within the spinlock, 1994 see comment near end of drbd_worker() */ 1995 spin_unlock_irqrestore(&q->q_lock, flags); 1996 } 1997 1998 static inline void wake_asender(struct drbd_conf *mdev) 1999 { 2000 if (test_bit(SIGNAL_ASENDER, &mdev->flags)) 2001 force_sig(DRBD_SIG, mdev->asender.task); 2002 } 2003 2004 static inline void request_ping(struct drbd_conf *mdev) 2005 { 2006 set_bit(SEND_PING, &mdev->flags); 2007 wake_asender(mdev); 2008 } 2009 2010 static inline int drbd_send_short_cmd(struct drbd_conf *mdev, 2011 enum drbd_packets cmd) 2012 { 2013 struct p_header80 h; 2014 return drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, &h, sizeof(h)); 2015 } 2016 2017 static inline int drbd_send_ping(struct drbd_conf *mdev) 2018 { 2019 struct p_header80 h; 2020 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING, &h, sizeof(h)); 2021 } 2022 2023 static inline int drbd_send_ping_ack(struct drbd_conf *mdev) 2024 { 2025 struct p_header80 h; 2026 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING_ACK, &h, sizeof(h)); 2027 } 2028 2029 static inline void drbd_thread_stop(struct drbd_thread *thi) 2030 { 2031 _drbd_thread_stop(thi, false, true); 2032 } 2033 2034 static inline void drbd_thread_stop_nowait(struct drbd_thread *thi) 2035 { 2036 _drbd_thread_stop(thi, false, false); 2037 } 2038 2039 static inline void drbd_thread_restart_nowait(struct drbd_thread *thi) 2040 { 2041 _drbd_thread_stop(thi, true, false); 2042 } 2043 2044 /* counts how many answer packets packets we expect from our peer, 2045 * for either explicit application requests, 2046 * or implicit barrier packets as necessary. 2047 * increased: 2048 * w_send_barrier 2049 * _req_mod(req, queue_for_net_write or queue_for_net_read); 2050 * it is much easier and equally valid to count what we queue for the 2051 * worker, even before it actually was queued or send. 2052 * (drbd_make_request_common; recovery path on read io-error) 2053 * decreased: 2054 * got_BarrierAck (respective tl_clear, tl_clear_barrier) 2055 * _req_mod(req, data_received) 2056 * [from receive_DataReply] 2057 * _req_mod(req, write_acked_by_peer or recv_acked_by_peer or neg_acked) 2058 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)] 2059 * for some reason it is NOT decreased in got_NegAck, 2060 * but in the resulting cleanup code from report_params. 2061 * we should try to remember the reason for that... 2062 * _req_mod(req, send_failed or send_canceled) 2063 * _req_mod(req, connection_lost_while_pending) 2064 * [from tl_clear_barrier] 2065 */ 2066 static inline void inc_ap_pending(struct drbd_conf *mdev) 2067 { 2068 atomic_inc(&mdev->ap_pending_cnt); 2069 } 2070 2071 #define ERR_IF_CNT_IS_NEGATIVE(which) \ 2072 if (atomic_read(&mdev->which) < 0) \ 2073 dev_err(DEV, "in %s:%d: " #which " = %d < 0 !\n", \ 2074 __func__ , __LINE__ , \ 2075 atomic_read(&mdev->which)) 2076 2077 #define dec_ap_pending(mdev) do { \ 2078 typecheck(struct drbd_conf *, mdev); \ 2079 if (atomic_dec_and_test(&mdev->ap_pending_cnt)) \ 2080 wake_up(&mdev->misc_wait); \ 2081 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt); } while (0) 2082 2083 /* counts how many resync-related answers we still expect from the peer 2084 * increase decrease 2085 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY) 2086 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK with ID_SYNCER) 2087 * (or P_NEG_ACK with ID_SYNCER) 2088 */ 2089 static inline void inc_rs_pending(struct drbd_conf *mdev) 2090 { 2091 atomic_inc(&mdev->rs_pending_cnt); 2092 } 2093 2094 #define dec_rs_pending(mdev) do { \ 2095 typecheck(struct drbd_conf *, mdev); \ 2096 atomic_dec(&mdev->rs_pending_cnt); \ 2097 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt); } while (0) 2098 2099 /* counts how many answers we still need to send to the peer. 2100 * increased on 2101 * receive_Data unless protocol A; 2102 * we need to send a P_RECV_ACK (proto B) 2103 * or P_WRITE_ACK (proto C) 2104 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK 2105 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA 2106 * receive_Barrier_* we need to send a P_BARRIER_ACK 2107 */ 2108 static inline void inc_unacked(struct drbd_conf *mdev) 2109 { 2110 atomic_inc(&mdev->unacked_cnt); 2111 } 2112 2113 #define dec_unacked(mdev) do { \ 2114 typecheck(struct drbd_conf *, mdev); \ 2115 atomic_dec(&mdev->unacked_cnt); \ 2116 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 2117 2118 #define sub_unacked(mdev, n) do { \ 2119 typecheck(struct drbd_conf *, mdev); \ 2120 atomic_sub(n, &mdev->unacked_cnt); \ 2121 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0) 2122 2123 2124 static inline void put_net_conf(struct drbd_conf *mdev) 2125 { 2126 if (atomic_dec_and_test(&mdev->net_cnt)) 2127 wake_up(&mdev->net_cnt_wait); 2128 } 2129 2130 /** 2131 * get_net_conf() - Increase ref count on mdev->net_conf; Returns 0 if nothing there 2132 * @mdev: DRBD device. 2133 * 2134 * You have to call put_net_conf() when finished working with mdev->net_conf. 2135 */ 2136 static inline int get_net_conf(struct drbd_conf *mdev) 2137 { 2138 int have_net_conf; 2139 2140 atomic_inc(&mdev->net_cnt); 2141 have_net_conf = mdev->state.conn >= C_UNCONNECTED; 2142 if (!have_net_conf) 2143 put_net_conf(mdev); 2144 return have_net_conf; 2145 } 2146 2147 /** 2148 * get_ldev() - Increase the ref count on mdev->ldev. Returns 0 if there is no ldev 2149 * @M: DRBD device. 2150 * 2151 * You have to call put_ldev() when finished working with mdev->ldev. 2152 */ 2153 #define get_ldev(M) __cond_lock(local, _get_ldev_if_state(M,D_INCONSISTENT)) 2154 #define get_ldev_if_state(M,MINS) __cond_lock(local, _get_ldev_if_state(M,MINS)) 2155 2156 static inline void put_ldev(struct drbd_conf *mdev) 2157 { 2158 int i = atomic_dec_return(&mdev->local_cnt); 2159 2160 /* This may be called from some endio handler, 2161 * so we must not sleep here. */ 2162 2163 __release(local); 2164 D_ASSERT(i >= 0); 2165 if (i == 0) { 2166 if (mdev->state.disk == D_DISKLESS) 2167 /* even internal references gone, safe to destroy */ 2168 drbd_ldev_destroy(mdev); 2169 if (mdev->state.disk == D_FAILED) 2170 /* all application IO references gone. */ 2171 drbd_go_diskless(mdev); 2172 wake_up(&mdev->misc_wait); 2173 } 2174 } 2175 2176 #ifndef __CHECKER__ 2177 static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins) 2178 { 2179 int io_allowed; 2180 2181 /* never get a reference while D_DISKLESS */ 2182 if (mdev->state.disk == D_DISKLESS) 2183 return 0; 2184 2185 atomic_inc(&mdev->local_cnt); 2186 io_allowed = (mdev->state.disk >= mins); 2187 if (!io_allowed) 2188 put_ldev(mdev); 2189 return io_allowed; 2190 } 2191 #else 2192 extern int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins); 2193 #endif 2194 2195 /* you must have an "get_ldev" reference */ 2196 static inline void drbd_get_syncer_progress(struct drbd_conf *mdev, 2197 unsigned long *bits_left, unsigned int *per_mil_done) 2198 { 2199 /* this is to break it at compile time when we change that, in case we 2200 * want to support more than (1<<32) bits on a 32bit arch. */ 2201 typecheck(unsigned long, mdev->rs_total); 2202 2203 /* note: both rs_total and rs_left are in bits, i.e. in 2204 * units of BM_BLOCK_SIZE. 2205 * for the percentage, we don't care. */ 2206 2207 if (mdev->state.conn == C_VERIFY_S || mdev->state.conn == C_VERIFY_T) 2208 *bits_left = mdev->ov_left; 2209 else 2210 *bits_left = drbd_bm_total_weight(mdev) - mdev->rs_failed; 2211 /* >> 10 to prevent overflow, 2212 * +1 to prevent division by zero */ 2213 if (*bits_left > mdev->rs_total) { 2214 /* doh. maybe a logic bug somewhere. 2215 * may also be just a race condition 2216 * between this and a disconnect during sync. 2217 * for now, just prevent in-kernel buffer overflow. 2218 */ 2219 smp_rmb(); 2220 dev_warn(DEV, "cs:%s rs_left=%lu > rs_total=%lu (rs_failed %lu)\n", 2221 drbd_conn_str(mdev->state.conn), 2222 *bits_left, mdev->rs_total, mdev->rs_failed); 2223 *per_mil_done = 0; 2224 } else { 2225 /* Make sure the division happens in long context. 2226 * We allow up to one petabyte storage right now, 2227 * at a granularity of 4k per bit that is 2**38 bits. 2228 * After shift right and multiplication by 1000, 2229 * this should still fit easily into a 32bit long, 2230 * so we don't need a 64bit division on 32bit arch. 2231 * Note: currently we don't support such large bitmaps on 32bit 2232 * arch anyways, but no harm done to be prepared for it here. 2233 */ 2234 unsigned int shift = mdev->rs_total >= (1ULL << 32) ? 16 : 10; 2235 unsigned long left = *bits_left >> shift; 2236 unsigned long total = 1UL + (mdev->rs_total >> shift); 2237 unsigned long tmp = 1000UL - left * 1000UL/total; 2238 *per_mil_done = tmp; 2239 } 2240 } 2241 2242 2243 /* this throttles on-the-fly application requests 2244 * according to max_buffers settings; 2245 * maybe re-implement using semaphores? */ 2246 static inline int drbd_get_max_buffers(struct drbd_conf *mdev) 2247 { 2248 int mxb = 1000000; /* arbitrary limit on open requests */ 2249 if (get_net_conf(mdev)) { 2250 mxb = mdev->net_conf->max_buffers; 2251 put_net_conf(mdev); 2252 } 2253 return mxb; 2254 } 2255 2256 static inline int drbd_state_is_stable(struct drbd_conf *mdev) 2257 { 2258 union drbd_state s = mdev->state; 2259 2260 /* DO NOT add a default clause, we want the compiler to warn us 2261 * for any newly introduced state we may have forgotten to add here */ 2262 2263 switch ((enum drbd_conns)s.conn) { 2264 /* new io only accepted when there is no connection, ... */ 2265 case C_STANDALONE: 2266 case C_WF_CONNECTION: 2267 /* ... or there is a well established connection. */ 2268 case C_CONNECTED: 2269 case C_SYNC_SOURCE: 2270 case C_SYNC_TARGET: 2271 case C_VERIFY_S: 2272 case C_VERIFY_T: 2273 case C_PAUSED_SYNC_S: 2274 case C_PAUSED_SYNC_T: 2275 case C_AHEAD: 2276 case C_BEHIND: 2277 /* transitional states, IO allowed */ 2278 case C_DISCONNECTING: 2279 case C_UNCONNECTED: 2280 case C_TIMEOUT: 2281 case C_BROKEN_PIPE: 2282 case C_NETWORK_FAILURE: 2283 case C_PROTOCOL_ERROR: 2284 case C_TEAR_DOWN: 2285 case C_WF_REPORT_PARAMS: 2286 case C_STARTING_SYNC_S: 2287 case C_STARTING_SYNC_T: 2288 break; 2289 2290 /* Allow IO in BM exchange states with new protocols */ 2291 case C_WF_BITMAP_S: 2292 if (mdev->agreed_pro_version < 96) 2293 return 0; 2294 break; 2295 2296 /* no new io accepted in these states */ 2297 case C_WF_BITMAP_T: 2298 case C_WF_SYNC_UUID: 2299 case C_MASK: 2300 /* not "stable" */ 2301 return 0; 2302 } 2303 2304 switch ((enum drbd_disk_state)s.disk) { 2305 case D_DISKLESS: 2306 case D_INCONSISTENT: 2307 case D_OUTDATED: 2308 case D_CONSISTENT: 2309 case D_UP_TO_DATE: 2310 /* disk state is stable as well. */ 2311 break; 2312 2313 /* no new io accepted during tansitional states */ 2314 case D_ATTACHING: 2315 case D_FAILED: 2316 case D_NEGOTIATING: 2317 case D_UNKNOWN: 2318 case D_MASK: 2319 /* not "stable" */ 2320 return 0; 2321 } 2322 2323 return 1; 2324 } 2325 2326 static inline int is_susp(union drbd_state s) 2327 { 2328 return s.susp || s.susp_nod || s.susp_fen; 2329 } 2330 2331 static inline bool may_inc_ap_bio(struct drbd_conf *mdev) 2332 { 2333 int mxb = drbd_get_max_buffers(mdev); 2334 2335 if (is_susp(mdev->state)) 2336 return false; 2337 if (test_bit(SUSPEND_IO, &mdev->flags)) 2338 return false; 2339 2340 /* to avoid potential deadlock or bitmap corruption, 2341 * in various places, we only allow new application io 2342 * to start during "stable" states. */ 2343 2344 /* no new io accepted when attaching or detaching the disk */ 2345 if (!drbd_state_is_stable(mdev)) 2346 return false; 2347 2348 /* since some older kernels don't have atomic_add_unless, 2349 * and we are within the spinlock anyways, we have this workaround. */ 2350 if (atomic_read(&mdev->ap_bio_cnt) > mxb) 2351 return false; 2352 if (test_bit(BITMAP_IO, &mdev->flags)) 2353 return false; 2354 return true; 2355 } 2356 2357 static inline bool inc_ap_bio_cond(struct drbd_conf *mdev, int count) 2358 { 2359 bool rv = false; 2360 2361 spin_lock_irq(&mdev->req_lock); 2362 rv = may_inc_ap_bio(mdev); 2363 if (rv) 2364 atomic_add(count, &mdev->ap_bio_cnt); 2365 spin_unlock_irq(&mdev->req_lock); 2366 2367 return rv; 2368 } 2369 2370 static inline void inc_ap_bio(struct drbd_conf *mdev, int count) 2371 { 2372 /* we wait here 2373 * as long as the device is suspended 2374 * until the bitmap is no longer on the fly during connection 2375 * handshake as long as we would exeed the max_buffer limit. 2376 * 2377 * to avoid races with the reconnect code, 2378 * we need to atomic_inc within the spinlock. */ 2379 2380 wait_event(mdev->misc_wait, inc_ap_bio_cond(mdev, count)); 2381 } 2382 2383 static inline void dec_ap_bio(struct drbd_conf *mdev) 2384 { 2385 int mxb = drbd_get_max_buffers(mdev); 2386 int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt); 2387 2388 D_ASSERT(ap_bio >= 0); 2389 /* this currently does wake_up for every dec_ap_bio! 2390 * maybe rather introduce some type of hysteresis? 2391 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */ 2392 if (ap_bio < mxb) 2393 wake_up(&mdev->misc_wait); 2394 if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) { 2395 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags)) 2396 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w); 2397 } 2398 } 2399 2400 static inline int drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val) 2401 { 2402 int changed = mdev->ed_uuid != val; 2403 mdev->ed_uuid = val; 2404 return changed; 2405 } 2406 2407 static inline int seq_cmp(u32 a, u32 b) 2408 { 2409 /* we assume wrap around at 32bit. 2410 * for wrap around at 24bit (old atomic_t), 2411 * we'd have to 2412 * a <<= 8; b <<= 8; 2413 */ 2414 return (s32)(a) - (s32)(b); 2415 } 2416 #define seq_lt(a, b) (seq_cmp((a), (b)) < 0) 2417 #define seq_gt(a, b) (seq_cmp((a), (b)) > 0) 2418 #define seq_ge(a, b) (seq_cmp((a), (b)) >= 0) 2419 #define seq_le(a, b) (seq_cmp((a), (b)) <= 0) 2420 /* CAUTION: please no side effects in arguments! */ 2421 #define seq_max(a, b) ((u32)(seq_gt((a), (b)) ? (a) : (b))) 2422 2423 static inline void update_peer_seq(struct drbd_conf *mdev, unsigned int new_seq) 2424 { 2425 unsigned int m; 2426 spin_lock(&mdev->peer_seq_lock); 2427 m = seq_max(mdev->peer_seq, new_seq); 2428 mdev->peer_seq = m; 2429 spin_unlock(&mdev->peer_seq_lock); 2430 if (m == new_seq) 2431 wake_up(&mdev->seq_wait); 2432 } 2433 2434 static inline void drbd_update_congested(struct drbd_conf *mdev) 2435 { 2436 struct sock *sk = mdev->data.socket->sk; 2437 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5) 2438 set_bit(NET_CONGESTED, &mdev->flags); 2439 } 2440 2441 static inline int drbd_queue_order_type(struct drbd_conf *mdev) 2442 { 2443 /* sorry, we currently have no working implementation 2444 * of distributed TCQ stuff */ 2445 #ifndef QUEUE_ORDERED_NONE 2446 #define QUEUE_ORDERED_NONE 0 2447 #endif 2448 return QUEUE_ORDERED_NONE; 2449 } 2450 2451 static inline void drbd_md_flush(struct drbd_conf *mdev) 2452 { 2453 int r; 2454 2455 if (test_bit(MD_NO_FUA, &mdev->flags)) 2456 return; 2457 2458 r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL); 2459 if (r) { 2460 set_bit(MD_NO_FUA, &mdev->flags); 2461 dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r); 2462 } 2463 } 2464 2465 #endif 2466