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authorPhilipp Reisner <philipp.reisner@linbit.com>2009-09-25 19:07:19 -0400
committerJens Axboe <jens.axboe@oracle.com>2009-10-01 15:17:49 -0400
commitb411b3637fa71fce9cf2acf0639009500f5892fe (patch)
tree6b88e5202e0f137fef50e95b0441bcafdbf91990 /drivers/block/drbd/drbd_int.h
parent1a35e0f6443f4266dad4c569c55c57a9032596fa (diff)
The DRBD driver
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd/drbd_int.h')
-rw-r--r--drivers/block/drbd/drbd_int.h2258
1 files changed, 2258 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
new file mode 100644
index 000000000000..8da602e010bb
--- /dev/null
+++ b/drivers/block/drbd/drbd_int.h
@@ -0,0 +1,2258 @@
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/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
45#ifdef __CHECKER__
46# define __protected_by(x) __attribute__((require_context(x,1,999,"rdwr")))
47# define __protected_read_by(x) __attribute__((require_context(x,1,999,"read")))
48# define __protected_write_by(x) __attribute__((require_context(x,1,999,"write")))
49# define __must_hold(x) __attribute__((context(x,1,1), require_context(x,1,999,"call")))
50#else
51# define __protected_by(x)
52# define __protected_read_by(x)
53# define __protected_write_by(x)
54# define __must_hold(x)
55#endif
56
57#define __no_warn(lock, stmt) do { __acquire(lock); stmt; __release(lock); } while (0)
58
59/* module parameter, defined in drbd_main.c */
60extern unsigned int minor_count;
61extern int disable_sendpage;
62extern int allow_oos;
63extern unsigned int cn_idx;
64
65#ifdef CONFIG_DRBD_FAULT_INJECTION
66extern int enable_faults;
67extern int fault_rate;
68extern int fault_devs;
69#endif
70
71extern char usermode_helper[];
72
73
74#ifndef TRUE
75#define TRUE 1
76#endif
77#ifndef FALSE
78#define FALSE 0
79#endif
80
81/* I don't remember why XCPU ...
82 * This is used to wake the asender,
83 * and to interrupt sending the sending task
84 * on disconnect.
85 */
86#define DRBD_SIG SIGXCPU
87
88/* This is used to stop/restart our threads.
89 * Cannot use SIGTERM nor SIGKILL, since these
90 * are sent out by init on runlevel changes
91 * I choose SIGHUP for now.
92 */
93#define DRBD_SIGKILL SIGHUP
94
95/* All EEs on the free list should have ID_VACANT (== 0)
96 * freshly allocated EEs get !ID_VACANT (== 1)
97 * so if it says "cannot dereference null pointer at adress 0x00000001",
98 * it is most likely one of these :( */
99
100#define ID_IN_SYNC (4711ULL)
101#define ID_OUT_OF_SYNC (4712ULL)
102
103#define ID_SYNCER (-1ULL)
104#define ID_VACANT 0
105#define is_syncer_block_id(id) ((id) == ID_SYNCER)
106
107struct drbd_conf;
108
109
110/* to shorten dev_warn(DEV, "msg"); and relatives statements */
111#define DEV (disk_to_dev(mdev->vdisk))
112
113#define D_ASSERT(exp) if (!(exp)) \
114 dev_err(DEV, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__)
115
116#define ERR_IF(exp) if (({ \
117 int _b = (exp) != 0; \
118 if (_b) dev_err(DEV, "%s: (%s) in %s:%d\n", \
119 __func__, #exp, __FILE__, __LINE__); \
120 _b; \
121 }))
122
123/* Defines to control fault insertion */
124enum {
125 DRBD_FAULT_MD_WR = 0, /* meta data write */
126 DRBD_FAULT_MD_RD = 1, /* read */
127 DRBD_FAULT_RS_WR = 2, /* resync */
128 DRBD_FAULT_RS_RD = 3,
129 DRBD_FAULT_DT_WR = 4, /* data */
130 DRBD_FAULT_DT_RD = 5,
131 DRBD_FAULT_DT_RA = 6, /* data read ahead */
132 DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */
133 DRBD_FAULT_AL_EE = 8, /* alloc ee */
134
135 DRBD_FAULT_MAX,
136};
137
138extern void trace_drbd_resync(struct drbd_conf *mdev, int level, const char *fmt, ...);
139
140#ifdef CONFIG_DRBD_FAULT_INJECTION
141extern unsigned int
142_drbd_insert_fault(struct drbd_conf *mdev, unsigned int type);
143static inline int
144drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) {
145 return fault_rate &&
146 (enable_faults & (1<<type)) &&
147 _drbd_insert_fault(mdev, type);
148}
149#define FAULT_ACTIVE(_m, _t) (drbd_insert_fault((_m), (_t)))
150
151#else
152#define FAULT_ACTIVE(_m, _t) (0)
153#endif
154
155/* integer division, round _UP_ to the next integer */
156#define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0))
157/* usual integer division */
158#define div_floor(A, B) ((A)/(B))
159
160/* drbd_meta-data.c (still in drbd_main.c) */
161/* 4th incarnation of the disk layout. */
162#define DRBD_MD_MAGIC (DRBD_MAGIC+4)
163
164extern struct drbd_conf **minor_table;
165extern struct ratelimit_state drbd_ratelimit_state;
166
167/* on the wire */
168enum drbd_packets {
169 /* receiver (data socket) */
170 P_DATA = 0x00,
171 P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */
172 P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */
173 P_BARRIER = 0x03,
174 P_BITMAP = 0x04,
175 P_BECOME_SYNC_TARGET = 0x05,
176 P_BECOME_SYNC_SOURCE = 0x06,
177 P_UNPLUG_REMOTE = 0x07, /* Used at various times to hint the peer */
178 P_DATA_REQUEST = 0x08, /* Used to ask for a data block */
179 P_RS_DATA_REQUEST = 0x09, /* Used to ask for a data block for resync */
180 P_SYNC_PARAM = 0x0a,
181 P_PROTOCOL = 0x0b,
182 P_UUIDS = 0x0c,
183 P_SIZES = 0x0d,
184 P_STATE = 0x0e,
185 P_SYNC_UUID = 0x0f,
186 P_AUTH_CHALLENGE = 0x10,
187 P_AUTH_RESPONSE = 0x11,
188 P_STATE_CHG_REQ = 0x12,
189
190 /* asender (meta socket */
191 P_PING = 0x13,
192 P_PING_ACK = 0x14,
193 P_RECV_ACK = 0x15, /* Used in protocol B */
194 P_WRITE_ACK = 0x16, /* Used in protocol C */
195 P_RS_WRITE_ACK = 0x17, /* Is a P_WRITE_ACK, additionally call set_in_sync(). */
196 P_DISCARD_ACK = 0x18, /* Used in proto C, two-primaries conflict detection */
197 P_NEG_ACK = 0x19, /* Sent if local disk is unusable */
198 P_NEG_DREPLY = 0x1a, /* Local disk is broken... */
199 P_NEG_RS_DREPLY = 0x1b, /* Local disk is broken... */
200 P_BARRIER_ACK = 0x1c,
201 P_STATE_CHG_REPLY = 0x1d,
202
203 /* "new" commands, no longer fitting into the ordering scheme above */
204
205 P_OV_REQUEST = 0x1e, /* data socket */
206 P_OV_REPLY = 0x1f,
207 P_OV_RESULT = 0x20, /* meta socket */
208 P_CSUM_RS_REQUEST = 0x21, /* data socket */
209 P_RS_IS_IN_SYNC = 0x22, /* meta socket */
210 P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */
211 P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */
212
213 P_MAX_CMD = 0x25,
214 P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */
215 P_MAX_OPT_CMD = 0x101,
216
217 /* special command ids for handshake */
218
219 P_HAND_SHAKE_M = 0xfff1, /* First Packet on the MetaSock */
220 P_HAND_SHAKE_S = 0xfff2, /* First Packet on the Socket */
221
222 P_HAND_SHAKE = 0xfffe /* FIXED for the next century! */
223};
224
225static inline const char *cmdname(enum drbd_packets cmd)
226{
227 /* THINK may need to become several global tables
228 * when we want to support more than
229 * one PRO_VERSION */
230 static const char *cmdnames[] = {
231 [P_DATA] = "Data",
232 [P_DATA_REPLY] = "DataReply",
233 [P_RS_DATA_REPLY] = "RSDataReply",
234 [P_BARRIER] = "Barrier",
235 [P_BITMAP] = "ReportBitMap",
236 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget",
237 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource",
238 [P_UNPLUG_REMOTE] = "UnplugRemote",
239 [P_DATA_REQUEST] = "DataRequest",
240 [P_RS_DATA_REQUEST] = "RSDataRequest",
241 [P_SYNC_PARAM] = "SyncParam",
242 [P_SYNC_PARAM89] = "SyncParam89",
243 [P_PROTOCOL] = "ReportProtocol",
244 [P_UUIDS] = "ReportUUIDs",
245 [P_SIZES] = "ReportSizes",
246 [P_STATE] = "ReportState",
247 [P_SYNC_UUID] = "ReportSyncUUID",
248 [P_AUTH_CHALLENGE] = "AuthChallenge",
249 [P_AUTH_RESPONSE] = "AuthResponse",
250 [P_PING] = "Ping",
251 [P_PING_ACK] = "PingAck",
252 [P_RECV_ACK] = "RecvAck",
253 [P_WRITE_ACK] = "WriteAck",
254 [P_RS_WRITE_ACK] = "RSWriteAck",
255 [P_DISCARD_ACK] = "DiscardAck",
256 [P_NEG_ACK] = "NegAck",
257 [P_NEG_DREPLY] = "NegDReply",
258 [P_NEG_RS_DREPLY] = "NegRSDReply",
259 [P_BARRIER_ACK] = "BarrierAck",
260 [P_STATE_CHG_REQ] = "StateChgRequest",
261 [P_STATE_CHG_REPLY] = "StateChgReply",
262 [P_OV_REQUEST] = "OVRequest",
263 [P_OV_REPLY] = "OVReply",
264 [P_OV_RESULT] = "OVResult",
265 [P_MAX_CMD] = NULL,
266 };
267
268 if (cmd == P_HAND_SHAKE_M)
269 return "HandShakeM";
270 if (cmd == P_HAND_SHAKE_S)
271 return "HandShakeS";
272 if (cmd == P_HAND_SHAKE)
273 return "HandShake";
274 if (cmd >= P_MAX_CMD)
275 return "Unknown";
276 return cmdnames[cmd];
277}
278
279/* for sending/receiving the bitmap,
280 * possibly in some encoding scheme */
281struct bm_xfer_ctx {
282 /* "const"
283 * stores total bits and long words
284 * of the bitmap, so we don't need to
285 * call the accessor functions over and again. */
286 unsigned long bm_bits;
287 unsigned long bm_words;
288 /* during xfer, current position within the bitmap */
289 unsigned long bit_offset;
290 unsigned long word_offset;
291
292 /* statistics; index: (h->command == P_BITMAP) */
293 unsigned packets[2];
294 unsigned bytes[2];
295};
296
297extern void INFO_bm_xfer_stats(struct drbd_conf *mdev,
298 const char *direction, struct bm_xfer_ctx *c);
299
300static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c)
301{
302 /* word_offset counts "native long words" (32 or 64 bit),
303 * aligned at 64 bit.
304 * Encoded packet may end at an unaligned bit offset.
305 * In case a fallback clear text packet is transmitted in
306 * between, we adjust this offset back to the last 64bit
307 * aligned "native long word", which makes coding and decoding
308 * the plain text bitmap much more convenient. */
309#if BITS_PER_LONG == 64
310 c->word_offset = c->bit_offset >> 6;
311#elif BITS_PER_LONG == 32
312 c->word_offset = c->bit_offset >> 5;
313 c->word_offset &= ~(1UL);
314#else
315# error "unsupported BITS_PER_LONG"
316#endif
317}
318
319#ifndef __packed
320#define __packed __attribute__((packed))
321#endif
322
323/* This is the layout for a packet on the wire.
324 * The byteorder is the network byte order.
325 * (except block_id and barrier fields.
326 * these are pointers to local structs
327 * and have no relevance for the partner,
328 * which just echoes them as received.)
329 *
330 * NOTE that the payload starts at a long aligned offset,
331 * regardless of 32 or 64 bit arch!
332 */
333struct p_header {
334 u32 magic;
335 u16 command;
336 u16 length; /* bytes of data after this header */
337 u8 payload[0];
338} __packed;
339/* 8 bytes. packet FIXED for the next century! */
340
341/*
342 * short commands, packets without payload, plain p_header:
343 * P_PING
344 * P_PING_ACK
345 * P_BECOME_SYNC_TARGET
346 * P_BECOME_SYNC_SOURCE
347 * P_UNPLUG_REMOTE
348 */
349
350/*
351 * commands with out-of-struct payload:
352 * P_BITMAP (no additional fields)
353 * P_DATA, P_DATA_REPLY (see p_data)
354 * P_COMPRESSED_BITMAP (see receive_compressed_bitmap)
355 */
356
357/* these defines must not be changed without changing the protocol version */
358#define DP_HARDBARRIER 1
359#define DP_RW_SYNC 2
360#define DP_MAY_SET_IN_SYNC 4
361
362struct p_data {
363 struct p_header head;
364 u64 sector; /* 64 bits sector number */
365 u64 block_id; /* to identify the request in protocol B&C */
366 u32 seq_num;
367 u32 dp_flags;
368} __packed;
369
370/*
371 * commands which share a struct:
372 * p_block_ack:
373 * P_RECV_ACK (proto B), P_WRITE_ACK (proto C),
374 * P_DISCARD_ACK (proto C, two-primaries conflict detection)
375 * p_block_req:
376 * P_DATA_REQUEST, P_RS_DATA_REQUEST
377 */
378struct p_block_ack {
379 struct p_header head;
380 u64 sector;
381 u64 block_id;
382 u32 blksize;
383 u32 seq_num;
384} __packed;
385
386
387struct p_block_req {
388 struct p_header head;
389 u64 sector;
390 u64 block_id;
391 u32 blksize;
392 u32 pad; /* to multiple of 8 Byte */
393} __packed;
394
395/*
396 * commands with their own struct for additional fields:
397 * P_HAND_SHAKE
398 * P_BARRIER
399 * P_BARRIER_ACK
400 * P_SYNC_PARAM
401 * ReportParams
402 */
403
404struct p_handshake {
405 struct p_header head; /* 8 bytes */
406 u32 protocol_min;
407 u32 feature_flags;
408 u32 protocol_max;
409
410 /* should be more than enough for future enhancements
411 * for now, feature_flags and the reserverd array shall be zero.
412 */
413
414 u32 _pad;
415 u64 reserverd[7];
416} __packed;
417/* 80 bytes, FIXED for the next century */
418
419struct p_barrier {
420 struct p_header head;
421 u32 barrier; /* barrier number _handle_ only */
422 u32 pad; /* to multiple of 8 Byte */
423} __packed;
424
425struct p_barrier_ack {
426 struct p_header head;
427 u32 barrier;
428 u32 set_size;
429} __packed;
430
431struct p_rs_param {
432 struct p_header head;
433 u32 rate;
434
435 /* Since protocol version 88 and higher. */
436 char verify_alg[0];
437} __packed;
438
439struct p_rs_param_89 {
440 struct p_header head;
441 u32 rate;
442 /* protocol version 89: */
443 char verify_alg[SHARED_SECRET_MAX];
444 char csums_alg[SHARED_SECRET_MAX];
445} __packed;
446
447struct p_protocol {
448 struct p_header head;
449 u32 protocol;
450 u32 after_sb_0p;
451 u32 after_sb_1p;
452 u32 after_sb_2p;
453 u32 want_lose;
454 u32 two_primaries;
455
456 /* Since protocol version 87 and higher. */
457 char integrity_alg[0];
458
459} __packed;
460
461struct p_uuids {
462 struct p_header head;
463 u64 uuid[UI_EXTENDED_SIZE];
464} __packed;
465
466struct p_rs_uuid {
467 struct p_header head;
468 u64 uuid;
469} __packed;
470
471struct p_sizes {
472 struct p_header head;
473 u64 d_size; /* size of disk */
474 u64 u_size; /* user requested size */
475 u64 c_size; /* current exported size */
476 u32 max_segment_size; /* Maximal size of a BIO */
477 u32 queue_order_type;
478} __packed;
479
480struct p_state {
481 struct p_header head;
482 u32 state;
483} __packed;
484
485struct p_req_state {
486 struct p_header head;
487 u32 mask;
488 u32 val;
489} __packed;
490
491struct p_req_state_reply {
492 struct p_header head;
493 u32 retcode;
494} __packed;
495
496struct p_drbd06_param {
497 u64 size;
498 u32 state;
499 u32 blksize;
500 u32 protocol;
501 u32 version;
502 u32 gen_cnt[5];
503 u32 bit_map_gen[5];
504} __packed;
505
506struct p_discard {
507 struct p_header head;
508 u64 block_id;
509 u32 seq_num;
510 u32 pad;
511} __packed;
512
513/* Valid values for the encoding field.
514 * Bump proto version when changing this. */
515enum drbd_bitmap_code {
516 /* RLE_VLI_Bytes = 0,
517 * and other bit variants had been defined during
518 * algorithm evaluation. */
519 RLE_VLI_Bits = 2,
520};
521
522struct p_compressed_bm {
523 struct p_header head;
524 /* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code
525 * (encoding & 0x80): polarity (set/unset) of first runlength
526 * ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits
527 * used to pad up to head.length bytes
528 */
529 u8 encoding;
530
531 u8 code[0];
532} __packed;
533
534/* DCBP: Drbd Compressed Bitmap Packet ... */
535static inline enum drbd_bitmap_code
536DCBP_get_code(struct p_compressed_bm *p)
537{
538 return (enum drbd_bitmap_code)(p->encoding & 0x0f);
539}
540
541static inline void
542DCBP_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code)
543{
544 BUG_ON(code & ~0xf);
545 p->encoding = (p->encoding & ~0xf) | code;
546}
547
548static inline int
549DCBP_get_start(struct p_compressed_bm *p)
550{
551 return (p->encoding & 0x80) != 0;
552}
553
554static inline void
555DCBP_set_start(struct p_compressed_bm *p, int set)
556{
557 p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0);
558}
559
560static inline int
561DCBP_get_pad_bits(struct p_compressed_bm *p)
562{
563 return (p->encoding >> 4) & 0x7;
564}
565
566static inline void
567DCBP_set_pad_bits(struct p_compressed_bm *p, int n)
568{
569 BUG_ON(n & ~0x7);
570 p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4);
571}
572
573/* one bitmap packet, including the p_header,
574 * should fit within one _architecture independend_ page.
575 * so we need to use the fixed size 4KiB page size
576 * most architechtures have used for a long time.
577 */
578#define BM_PACKET_PAYLOAD_BYTES (4096 - sizeof(struct p_header))
579#define BM_PACKET_WORDS (BM_PACKET_PAYLOAD_BYTES/sizeof(long))
580#define BM_PACKET_VLI_BYTES_MAX (4096 - sizeof(struct p_compressed_bm))
581#if (PAGE_SIZE < 4096)
582/* drbd_send_bitmap / receive_bitmap would break horribly */
583#error "PAGE_SIZE too small"
584#endif
585
586union p_polymorph {
587 struct p_header header;
588 struct p_handshake handshake;
589 struct p_data data;
590 struct p_block_ack block_ack;
591 struct p_barrier barrier;
592 struct p_barrier_ack barrier_ack;
593 struct p_rs_param_89 rs_param_89;
594 struct p_protocol protocol;
595 struct p_sizes sizes;
596 struct p_uuids uuids;
597 struct p_state state;
598 struct p_req_state req_state;
599 struct p_req_state_reply req_state_reply;
600 struct p_block_req block_req;
601} __packed;
602
603/**********************************************************************/
604enum drbd_thread_state {
605 None,
606 Running,
607 Exiting,
608 Restarting
609};
610
611struct drbd_thread {
612 spinlock_t t_lock;
613 struct task_struct *task;
614 struct completion stop;
615 enum drbd_thread_state t_state;
616 int (*function) (struct drbd_thread *);
617 struct drbd_conf *mdev;
618 int reset_cpu_mask;
619};
620
621static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi)
622{
623 /* THINK testing the t_state seems to be uncritical in all cases
624 * (but thread_{start,stop}), so we can read it *without* the lock.
625 * --lge */
626
627 smp_rmb();
628 return thi->t_state;
629}
630
631
632/*
633 * Having this as the first member of a struct provides sort of "inheritance".
634 * "derived" structs can be "drbd_queue_work()"ed.
635 * The callback should know and cast back to the descendant struct.
636 * drbd_request and drbd_epoch_entry are descendants of drbd_work.
637 */
638struct drbd_work;
639typedef int (*drbd_work_cb)(struct drbd_conf *, struct drbd_work *, int cancel);
640struct drbd_work {
641 struct list_head list;
642 drbd_work_cb cb;
643};
644
645struct drbd_tl_epoch;
646struct drbd_request {
647 struct drbd_work w;
648 struct drbd_conf *mdev;
649
650 /* if local IO is not allowed, will be NULL.
651 * if local IO _is_ allowed, holds the locally submitted bio clone,
652 * or, after local IO completion, the ERR_PTR(error).
653 * see drbd_endio_pri(). */
654 struct bio *private_bio;
655
656 struct hlist_node colision;
657 sector_t sector;
658 unsigned int size;
659 unsigned int epoch; /* barrier_nr */
660
661 /* barrier_nr: used to check on "completion" whether this req was in
662 * the current epoch, and we therefore have to close it,
663 * starting a new epoch...
664 */
665
666 /* up to here, the struct layout is identical to drbd_epoch_entry;
667 * we might be able to use that to our advantage... */
668
669 struct list_head tl_requests; /* ring list in the transfer log */
670 struct bio *master_bio; /* master bio pointer */
671 unsigned long rq_state; /* see comments above _req_mod() */
672 int seq_num;
673 unsigned long start_time;
674};
675
676struct drbd_tl_epoch {
677 struct drbd_work w;
678 struct list_head requests; /* requests before */
679 struct drbd_tl_epoch *next; /* pointer to the next barrier */
680 unsigned int br_number; /* the barriers identifier. */
681 int n_req; /* number of requests attached before this barrier */
682};
683
684struct drbd_request;
685
686/* These Tl_epoch_entries may be in one of 6 lists:
687 active_ee .. data packet being written
688 sync_ee .. syncer block being written
689 done_ee .. block written, need to send P_WRITE_ACK
690 read_ee .. [RS]P_DATA_REQUEST being read
691*/
692
693struct drbd_epoch {
694 struct list_head list;
695 unsigned int barrier_nr;
696 atomic_t epoch_size; /* increased on every request added. */
697 atomic_t active; /* increased on every req. added, and dec on every finished. */
698 unsigned long flags;
699};
700
701/* drbd_epoch flag bits */
702enum {
703 DE_BARRIER_IN_NEXT_EPOCH_ISSUED,
704 DE_BARRIER_IN_NEXT_EPOCH_DONE,
705 DE_CONTAINS_A_BARRIER,
706 DE_HAVE_BARRIER_NUMBER,
707 DE_IS_FINISHING,
708};
709
710enum epoch_event {
711 EV_PUT,
712 EV_GOT_BARRIER_NR,
713 EV_BARRIER_DONE,
714 EV_BECAME_LAST,
715 EV_TRACE_FLUSH, /* TRACE_ are not real events, only used for tracing */
716 EV_TRACE_ADD_BARRIER, /* Doing the first write as a barrier write */
717 EV_TRACE_SETTING_BI, /* Barrier is expressed with the first write of the next epoch */
718 EV_TRACE_ALLOC,
719 EV_TRACE_FREE,
720 EV_CLEANUP = 32, /* used as flag */
721};
722
723struct drbd_epoch_entry {
724 struct drbd_work w;
725 struct drbd_conf *mdev;
726 struct bio *private_bio;
727 struct hlist_node colision;
728 sector_t sector;
729 unsigned int size;
730 struct drbd_epoch *epoch;
731
732 /* up to here, the struct layout is identical to drbd_request;
733 * we might be able to use that to our advantage... */
734
735 unsigned int flags;
736 u64 block_id;
737};
738
739struct drbd_wq_barrier {
740 struct drbd_work w;
741 struct completion done;
742};
743
744struct digest_info {
745 int digest_size;
746 void *digest;
747};
748
749/* ee flag bits */
750enum {
751 __EE_CALL_AL_COMPLETE_IO,
752 __EE_CONFLICT_PENDING,
753 __EE_MAY_SET_IN_SYNC,
754 __EE_IS_BARRIER,
755};
756#define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO)
757#define EE_CONFLICT_PENDING (1<<__EE_CONFLICT_PENDING)
758#define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC)
759#define EE_IS_BARRIER (1<<__EE_IS_BARRIER)
760
761/* global flag bits */
762enum {
763 CREATE_BARRIER, /* next P_DATA is preceeded by a P_BARRIER */
764 SIGNAL_ASENDER, /* whether asender wants to be interrupted */
765 SEND_PING, /* whether asender should send a ping asap */
766
767 STOP_SYNC_TIMER, /* tell timer to cancel itself */
768 UNPLUG_QUEUED, /* only relevant with kernel 2.4 */
769 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */
770 MD_DIRTY, /* current uuids and flags not yet on disk */
771 DISCARD_CONCURRENT, /* Set on one node, cleared on the peer! */
772 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */
773 CLUSTER_ST_CHANGE, /* Cluster wide state change going on... */
774 CL_ST_CHG_SUCCESS,
775 CL_ST_CHG_FAIL,
776 CRASHED_PRIMARY, /* This node was a crashed primary.
777 * Gets cleared when the state.conn
778 * goes into C_CONNECTED state. */
779 WRITE_BM_AFTER_RESYNC, /* A kmalloc() during resync failed */
780 NO_BARRIER_SUPP, /* underlying block device doesn't implement barriers */
781 CONSIDER_RESYNC,
782
783 MD_NO_BARRIER, /* meta data device does not support barriers,
784 so don't even try */
785 SUSPEND_IO, /* suspend application io */
786 BITMAP_IO, /* suspend application io;
787 once no more io in flight, start bitmap io */
788 BITMAP_IO_QUEUED, /* Started bitmap IO */
789 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */
790 NET_CONGESTED, /* The data socket is congested */
791
792 CONFIG_PENDING, /* serialization of (re)configuration requests.
793 * if set, also prevents the device from dying */
794 DEVICE_DYING, /* device became unconfigured,
795 * but worker thread is still handling the cleanup.
796 * reconfiguring (nl_disk_conf, nl_net_conf) is dissalowed,
797 * while this is set. */
798 RESIZE_PENDING, /* Size change detected locally, waiting for the response from
799 * the peer, if it changed there as well. */
800};
801
802struct drbd_bitmap; /* opaque for drbd_conf */
803
804/* TODO sort members for performance
805 * MAYBE group them further */
806
807/* THINK maybe we actually want to use the default "event/%s" worker threads
808 * or similar in linux 2.6, which uses per cpu data and threads.
809 *
810 * To be general, this might need a spin_lock member.
811 * For now, please use the mdev->req_lock to protect list_head,
812 * see drbd_queue_work below.
813 */
814struct drbd_work_queue {
815 struct list_head q;
816 struct semaphore s; /* producers up it, worker down()s it */
817 spinlock_t q_lock; /* to protect the list. */
818};
819
820struct drbd_socket {
821 struct drbd_work_queue work;
822 struct mutex mutex;
823 struct socket *socket;
824 /* this way we get our
825 * send/receive buffers off the stack */
826 union p_polymorph sbuf;
827 union p_polymorph rbuf;
828};
829
830struct drbd_md {
831 u64 md_offset; /* sector offset to 'super' block */
832
833 u64 la_size_sect; /* last agreed size, unit sectors */
834 u64 uuid[UI_SIZE];
835 u64 device_uuid;
836 u32 flags;
837 u32 md_size_sect;
838
839 s32 al_offset; /* signed relative sector offset to al area */
840 s32 bm_offset; /* signed relative sector offset to bitmap */
841
842 /* u32 al_nr_extents; important for restoring the AL
843 * is stored into sync_conf.al_extents, which in turn
844 * gets applied to act_log->nr_elements
845 */
846};
847
848/* for sync_conf and other types... */
849#define NL_PACKET(name, number, fields) struct name { fields };
850#define NL_INTEGER(pn,pr,member) int member;
851#define NL_INT64(pn,pr,member) __u64 member;
852#define NL_BIT(pn,pr,member) unsigned member:1;
853#define NL_STRING(pn,pr,member,len) unsigned char member[len]; int member ## _len;
854#include "linux/drbd_nl.h"
855
856struct drbd_backing_dev {
857 struct block_device *backing_bdev;
858 struct block_device *md_bdev;
859 struct file *lo_file;
860 struct file *md_file;
861 struct drbd_md md;
862 struct disk_conf dc; /* The user provided config... */
863 sector_t known_size; /* last known size of that backing device */
864};
865
866struct drbd_md_io {
867 struct drbd_conf *mdev;
868 struct completion event;
869 int error;
870};
871
872struct bm_io_work {
873 struct drbd_work w;
874 char *why;
875 int (*io_fn)(struct drbd_conf *mdev);
876 void (*done)(struct drbd_conf *mdev, int rv);
877};
878
879enum write_ordering_e {
880 WO_none,
881 WO_drain_io,
882 WO_bdev_flush,
883 WO_bio_barrier
884};
885
886struct drbd_conf {
887 /* things that are stored as / read from meta data on disk */
888 unsigned long flags;
889
890 /* configured by drbdsetup */
891 struct net_conf *net_conf; /* protected by get_net_conf() and put_net_conf() */
892 struct syncer_conf sync_conf;
893 struct drbd_backing_dev *ldev __protected_by(local);
894
895 sector_t p_size; /* partner's disk size */
896 struct request_queue *rq_queue;
897 struct block_device *this_bdev;
898 struct gendisk *vdisk;
899
900 struct drbd_socket data; /* data/barrier/cstate/parameter packets */
901 struct drbd_socket meta; /* ping/ack (metadata) packets */
902 int agreed_pro_version; /* actually used protocol version */
903 unsigned long last_received; /* in jiffies, either socket */
904 unsigned int ko_count;
905 struct drbd_work resync_work,
906 unplug_work,
907 md_sync_work;
908 struct timer_list resync_timer;
909 struct timer_list md_sync_timer;
910
911 /* Used after attach while negotiating new disk state. */
912 union drbd_state new_state_tmp;
913
914 union drbd_state state;
915 wait_queue_head_t misc_wait;
916 wait_queue_head_t state_wait; /* upon each state change. */
917 unsigned int send_cnt;
918 unsigned int recv_cnt;
919 unsigned int read_cnt;
920 unsigned int writ_cnt;
921 unsigned int al_writ_cnt;
922 unsigned int bm_writ_cnt;
923 atomic_t ap_bio_cnt; /* Requests we need to complete */
924 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */
925 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */
926 atomic_t unacked_cnt; /* Need to send replys for */
927 atomic_t local_cnt; /* Waiting for local completion */
928 atomic_t net_cnt; /* Users of net_conf */
929 spinlock_t req_lock;
930 struct drbd_tl_epoch *unused_spare_tle; /* for pre-allocation */
931 struct drbd_tl_epoch *newest_tle;
932 struct drbd_tl_epoch *oldest_tle;
933 struct list_head out_of_sequence_requests;
934 struct hlist_head *tl_hash;
935 unsigned int tl_hash_s;
936
937 /* blocks to sync in this run [unit BM_BLOCK_SIZE] */
938 unsigned long rs_total;
939 /* number of sync IOs that failed in this run */
940 unsigned long rs_failed;
941 /* Syncer's start time [unit jiffies] */
942 unsigned long rs_start;
943 /* cumulated time in PausedSyncX state [unit jiffies] */
944 unsigned long rs_paused;
945 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */
946 unsigned long rs_mark_left;
947 /* marks's time [unit jiffies] */
948 unsigned long rs_mark_time;
949 /* skipped because csum was equeal [unit BM_BLOCK_SIZE] */
950 unsigned long rs_same_csum;
951
952 /* where does the admin want us to start? (sector) */
953 sector_t ov_start_sector;
954 /* where are we now? (sector) */
955 sector_t ov_position;
956 /* Start sector of out of sync range (to merge printk reporting). */
957 sector_t ov_last_oos_start;
958 /* size of out-of-sync range in sectors. */
959 sector_t ov_last_oos_size;
960 unsigned long ov_left; /* in bits */
961 struct crypto_hash *csums_tfm;
962 struct crypto_hash *verify_tfm;
963
964 struct drbd_thread receiver;
965 struct drbd_thread worker;
966 struct drbd_thread asender;
967 struct drbd_bitmap *bitmap;
968 unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */
969
970 /* Used to track operations of resync... */
971 struct lru_cache *resync;
972 /* Number of locked elements in resync LRU */
973 unsigned int resync_locked;
974 /* resync extent number waiting for application requests */
975 unsigned int resync_wenr;
976
977 int open_cnt;
978 u64 *p_uuid;
979 struct drbd_epoch *current_epoch;
980 spinlock_t epoch_lock;
981 unsigned int epochs;
982 enum write_ordering_e write_ordering;
983 struct list_head active_ee; /* IO in progress */
984 struct list_head sync_ee; /* IO in progress */
985 struct list_head done_ee; /* send ack */
986 struct list_head read_ee; /* IO in progress */
987 struct list_head net_ee; /* zero-copy network send in progress */
988 struct hlist_head *ee_hash; /* is proteced by req_lock! */
989 unsigned int ee_hash_s;
990
991 /* this one is protected by ee_lock, single thread */
992 struct drbd_epoch_entry *last_write_w_barrier;
993
994 int next_barrier_nr;
995 struct hlist_head *app_reads_hash; /* is proteced by req_lock */
996 struct list_head resync_reads;
997 atomic_t pp_in_use;
998 wait_queue_head_t ee_wait;
999 struct page *md_io_page; /* one page buffer for md_io */
1000 struct page *md_io_tmpp; /* for logical_block_size != 512 */
1001 struct mutex md_io_mutex; /* protects the md_io_buffer */
1002 spinlock_t al_lock;
1003 wait_queue_head_t al_wait;
1004 struct lru_cache *act_log; /* activity log */
1005 unsigned int al_tr_number;
1006 int al_tr_cycle;
1007 int al_tr_pos; /* position of the next transaction in the journal */
1008 struct crypto_hash *cram_hmac_tfm;
1009 struct crypto_hash *integrity_w_tfm; /* to be used by the worker thread */
1010 struct crypto_hash *integrity_r_tfm; /* to be used by the receiver thread */
1011 void *int_dig_out;
1012 void *int_dig_in;
1013 void *int_dig_vv;
1014 wait_queue_head_t seq_wait;
1015 atomic_t packet_seq;
1016 unsigned int peer_seq;
1017 spinlock_t peer_seq_lock;
1018 unsigned int minor;
1019 unsigned long comm_bm_set; /* communicated number of set bits. */
1020 cpumask_var_t cpu_mask;
1021 struct bm_io_work bm_io_work;
1022 u64 ed_uuid; /* UUID of the exposed data */
1023 struct mutex state_mutex;
1024 char congestion_reason; /* Why we where congested... */
1025};
1026
1027static inline struct drbd_conf *minor_to_mdev(unsigned int minor)
1028{
1029 struct drbd_conf *mdev;
1030
1031 mdev = minor < minor_count ? minor_table[minor] : NULL;
1032
1033 return mdev;
1034}
1035
1036static inline unsigned int mdev_to_minor(struct drbd_conf *mdev)
1037{
1038 return mdev->minor;
1039}
1040
1041/* returns 1 if it was successfull,
1042 * returns 0 if there was no data socket.
1043 * so wherever you are going to use the data.socket, e.g. do
1044 * if (!drbd_get_data_sock(mdev))
1045 * return 0;
1046 * CODE();
1047 * drbd_put_data_sock(mdev);
1048 */
1049static inline int drbd_get_data_sock(struct drbd_conf *mdev)
1050{
1051 mutex_lock(&mdev->data.mutex);
1052 /* drbd_disconnect() could have called drbd_free_sock()
1053 * while we were waiting in down()... */
1054 if (unlikely(mdev->data.socket == NULL)) {
1055 mutex_unlock(&mdev->data.mutex);
1056 return 0;
1057 }
1058 return 1;
1059}
1060
1061static inline void drbd_put_data_sock(struct drbd_conf *mdev)
1062{
1063 mutex_unlock(&mdev->data.mutex);
1064}
1065
1066/*
1067 * function declarations
1068 *************************/
1069
1070/* drbd_main.c */
1071
1072enum chg_state_flags {
1073 CS_HARD = 1,
1074 CS_VERBOSE = 2,
1075 CS_WAIT_COMPLETE = 4,
1076 CS_SERIALIZE = 8,
1077 CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE,
1078};
1079
1080extern void drbd_init_set_defaults(struct drbd_conf *mdev);
1081extern int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
1082 union drbd_state mask, union drbd_state val);
1083extern void drbd_force_state(struct drbd_conf *, union drbd_state,
1084 union drbd_state);
1085extern int _drbd_request_state(struct drbd_conf *, union drbd_state,
1086 union drbd_state, enum chg_state_flags);
1087extern int __drbd_set_state(struct drbd_conf *, union drbd_state,
1088 enum chg_state_flags, struct completion *done);
1089extern void print_st_err(struct drbd_conf *, union drbd_state,
1090 union drbd_state, int);
1091extern int drbd_thread_start(struct drbd_thread *thi);
1092extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait);
1093#ifdef CONFIG_SMP
1094extern void drbd_thread_current_set_cpu(struct drbd_conf *mdev);
1095extern void drbd_calc_cpu_mask(struct drbd_conf *mdev);
1096#else
1097#define drbd_thread_current_set_cpu(A) ({})
1098#define drbd_calc_cpu_mask(A) ({})
1099#endif
1100extern void drbd_free_resources(struct drbd_conf *mdev);
1101extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
1102 unsigned int set_size);
1103extern void tl_clear(struct drbd_conf *mdev);
1104extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *);
1105extern void drbd_free_sock(struct drbd_conf *mdev);
1106extern int drbd_send(struct drbd_conf *mdev, struct socket *sock,
1107 void *buf, size_t size, unsigned msg_flags);
1108extern int drbd_send_protocol(struct drbd_conf *mdev);
1109extern int drbd_send_uuids(struct drbd_conf *mdev);
1110extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev);
1111extern int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val);
1112extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply);
1113extern int _drbd_send_state(struct drbd_conf *mdev);
1114extern int drbd_send_state(struct drbd_conf *mdev);
1115extern int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1116 enum drbd_packets cmd, struct p_header *h,
1117 size_t size, unsigned msg_flags);
1118#define USE_DATA_SOCKET 1
1119#define USE_META_SOCKET 0
1120extern int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1121 enum drbd_packets cmd, struct p_header *h,
1122 size_t size);
1123extern int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd,
1124 char *data, size_t size);
1125extern int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc);
1126extern int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr,
1127 u32 set_size);
1128extern int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
1129 struct drbd_epoch_entry *e);
1130extern int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
1131 struct p_block_req *rp);
1132extern int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
1133 struct p_data *dp);
1134extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
1135 sector_t sector, int blksize, u64 block_id);
1136extern int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
1137 struct drbd_epoch_entry *e);
1138extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req);
1139extern int _drbd_send_barrier(struct drbd_conf *mdev,
1140 struct drbd_tl_epoch *barrier);
1141extern int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
1142 sector_t sector, int size, u64 block_id);
1143extern int drbd_send_drequest_csum(struct drbd_conf *mdev,
1144 sector_t sector,int size,
1145 void *digest, int digest_size,
1146 enum drbd_packets cmd);
1147extern int drbd_send_ov_request(struct drbd_conf *mdev,sector_t sector,int size);
1148
1149extern int drbd_send_bitmap(struct drbd_conf *mdev);
1150extern int _drbd_send_bitmap(struct drbd_conf *mdev);
1151extern int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode);
1152extern void drbd_free_bc(struct drbd_backing_dev *ldev);
1153extern void drbd_mdev_cleanup(struct drbd_conf *mdev);
1154
1155/* drbd_meta-data.c (still in drbd_main.c) */
1156extern void drbd_md_sync(struct drbd_conf *mdev);
1157extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev);
1158/* maybe define them below as inline? */
1159extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local);
1160extern void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local);
1161extern void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local);
1162extern void _drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local);
1163extern void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local);
1164extern void drbd_md_set_flag(struct drbd_conf *mdev, int flags) __must_hold(local);
1165extern void drbd_md_clear_flag(struct drbd_conf *mdev, int flags)__must_hold(local);
1166extern int drbd_md_test_flag(struct drbd_backing_dev *, int);
1167extern void drbd_md_mark_dirty(struct drbd_conf *mdev);
1168extern void drbd_queue_bitmap_io(struct drbd_conf *mdev,
1169 int (*io_fn)(struct drbd_conf *),
1170 void (*done)(struct drbd_conf *, int),
1171 char *why);
1172extern int drbd_bmio_set_n_write(struct drbd_conf *mdev);
1173extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev);
1174extern int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why);
1175
1176
1177/* Meta data layout
1178 We reserve a 128MB Block (4k aligned)
1179 * either at the end of the backing device
1180 * or on a seperate meta data device. */
1181
1182#define MD_RESERVED_SECT (128LU << 11) /* 128 MB, unit sectors */
1183/* The following numbers are sectors */
1184#define MD_AL_OFFSET 8 /* 8 Sectors after start of meta area */
1185#define MD_AL_MAX_SIZE 64 /* = 32 kb LOG ~ 3776 extents ~ 14 GB Storage */
1186/* Allows up to about 3.8TB */
1187#define MD_BM_OFFSET (MD_AL_OFFSET + MD_AL_MAX_SIZE)
1188
1189/* Since the smalles IO unit is usually 512 byte */
1190#define MD_SECTOR_SHIFT 9
1191#define MD_SECTOR_SIZE (1<<MD_SECTOR_SHIFT)
1192
1193/* activity log */
1194#define AL_EXTENTS_PT ((MD_SECTOR_SIZE-12)/8-1) /* 61 ; Extents per 512B sector */
1195#define AL_EXTENT_SHIFT 22 /* One extent represents 4M Storage */
1196#define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT)
1197
1198#if BITS_PER_LONG == 32
1199#define LN2_BPL 5
1200#define cpu_to_lel(A) cpu_to_le32(A)
1201#define lel_to_cpu(A) le32_to_cpu(A)
1202#elif BITS_PER_LONG == 64
1203#define LN2_BPL 6
1204#define cpu_to_lel(A) cpu_to_le64(A)
1205#define lel_to_cpu(A) le64_to_cpu(A)
1206#else
1207#error "LN2 of BITS_PER_LONG unknown!"
1208#endif
1209
1210/* resync bitmap */
1211/* 16MB sized 'bitmap extent' to track syncer usage */
1212struct bm_extent {
1213 int rs_left; /* number of bits set (out of sync) in this extent. */
1214 int rs_failed; /* number of failed resync requests in this extent. */
1215 unsigned long flags;
1216 struct lc_element lce;
1217};
1218
1219#define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */
1220#define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */
1221
1222/* drbd_bitmap.c */
1223/*
1224 * We need to store one bit for a block.
1225 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap.
1226 * Bit 0 ==> local node thinks this block is binary identical on both nodes
1227 * Bit 1 ==> local node thinks this block needs to be synced.
1228 */
1229
1230#define BM_BLOCK_SHIFT 12 /* 4k per bit */
1231#define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT)
1232/* (9+3) : 512 bytes @ 8 bits; representing 16M storage
1233 * per sector of on disk bitmap */
1234#define BM_EXT_SHIFT (BM_BLOCK_SHIFT + MD_SECTOR_SHIFT + 3) /* = 24 */
1235#define BM_EXT_SIZE (1<<BM_EXT_SHIFT)
1236
1237#if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12)
1238#error "HAVE YOU FIXED drbdmeta AS WELL??"
1239#endif
1240
1241/* thus many _storage_ sectors are described by one bit */
1242#define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9))
1243#define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9))
1244#define BM_SECT_PER_BIT BM_BIT_TO_SECT(1)
1245
1246/* bit to represented kilo byte conversion */
1247#define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10))
1248
1249/* in which _bitmap_ extent (resp. sector) the bit for a certain
1250 * _storage_ sector is located in */
1251#define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9))
1252
1253/* how much _storage_ sectors we have per bitmap sector */
1254#define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9))
1255#define BM_SECT_PER_EXT BM_EXT_TO_SECT(1)
1256
1257/* in one sector of the bitmap, we have this many activity_log extents. */
1258#define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT))
1259#define BM_WORDS_PER_AL_EXT (1 << (AL_EXTENT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL))
1260
1261#define BM_BLOCKS_PER_BM_EXT_B (BM_EXT_SHIFT - BM_BLOCK_SHIFT)
1262#define BM_BLOCKS_PER_BM_EXT_MASK ((1<<BM_BLOCKS_PER_BM_EXT_B) - 1)
1263
1264/* the extent in "PER_EXTENT" below is an activity log extent
1265 * we need that many (long words/bytes) to store the bitmap
1266 * of one AL_EXTENT_SIZE chunk of storage.
1267 * we can store the bitmap for that many AL_EXTENTS within
1268 * one sector of the _on_disk_ bitmap:
1269 * bit 0 bit 37 bit 38 bit (512*8)-1
1270 * ...|........|........|.. // ..|........|
1271 * sect. 0 `296 `304 ^(512*8*8)-1
1272 *
1273#define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG )
1274#define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128
1275#define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4
1276 */
1277
1278#define DRBD_MAX_SECTORS_32 (0xffffffffLU)
1279#define DRBD_MAX_SECTORS_BM \
1280 ((MD_RESERVED_SECT - MD_BM_OFFSET) * (1LL<<(BM_EXT_SHIFT-9)))
1281#if DRBD_MAX_SECTORS_BM < DRBD_MAX_SECTORS_32
1282#define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM
1283#define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_BM
1284#elif !defined(CONFIG_LBD) && BITS_PER_LONG == 32
1285#define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_32
1286#define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_32
1287#else
1288#define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM
1289/* 16 TB in units of sectors */
1290#if BITS_PER_LONG == 32
1291/* adjust by one page worth of bitmap,
1292 * so we won't wrap around in drbd_bm_find_next_bit.
1293 * you should use 64bit OS for that much storage, anyways. */
1294#define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff)
1295#else
1296#define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0x1LU << 32)
1297#endif
1298#endif
1299
1300/* Sector shift value for the "hash" functions of tl_hash and ee_hash tables.
1301 * With a value of 6 all IO in one 32K block make it to the same slot of the
1302 * hash table. */
1303#define HT_SHIFT 6
1304#define DRBD_MAX_SEGMENT_SIZE (1U<<(9+HT_SHIFT))
1305
1306/* Number of elements in the app_reads_hash */
1307#define APP_R_HSIZE 15
1308
1309extern int drbd_bm_init(struct drbd_conf *mdev);
1310extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors);
1311extern void drbd_bm_cleanup(struct drbd_conf *mdev);
1312extern void drbd_bm_set_all(struct drbd_conf *mdev);
1313extern void drbd_bm_clear_all(struct drbd_conf *mdev);
1314extern int drbd_bm_set_bits(
1315 struct drbd_conf *mdev, unsigned long s, unsigned long e);
1316extern int drbd_bm_clear_bits(
1317 struct drbd_conf *mdev, unsigned long s, unsigned long e);
1318/* bm_set_bits variant for use while holding drbd_bm_lock */
1319extern void _drbd_bm_set_bits(struct drbd_conf *mdev,
1320 const unsigned long s, const unsigned long e);
1321extern int drbd_bm_test_bit(struct drbd_conf *mdev, unsigned long bitnr);
1322extern int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr);
1323extern int drbd_bm_write_sect(struct drbd_conf *mdev, unsigned long enr) __must_hold(local);
1324extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local);
1325extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local);
1326extern unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev,
1327 unsigned long al_enr);
1328extern size_t drbd_bm_words(struct drbd_conf *mdev);
1329extern unsigned long drbd_bm_bits(struct drbd_conf *mdev);
1330extern sector_t drbd_bm_capacity(struct drbd_conf *mdev);
1331extern unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo);
1332/* bm_find_next variants for use while you hold drbd_bm_lock() */
1333extern unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo);
1334extern unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo);
1335extern unsigned long drbd_bm_total_weight(struct drbd_conf *mdev);
1336extern int drbd_bm_rs_done(struct drbd_conf *mdev);
1337/* for receive_bitmap */
1338extern void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset,
1339 size_t number, unsigned long *buffer);
1340/* for _drbd_send_bitmap and drbd_bm_write_sect */
1341extern void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset,
1342 size_t number, unsigned long *buffer);
1343
1344extern void drbd_bm_lock(struct drbd_conf *mdev, char *why);
1345extern void drbd_bm_unlock(struct drbd_conf *mdev);
1346
1347extern int drbd_bm_count_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e);
1348/* drbd_main.c */
1349
1350extern struct kmem_cache *drbd_request_cache;
1351extern struct kmem_cache *drbd_ee_cache; /* epoch entries */
1352extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
1353extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
1354extern mempool_t *drbd_request_mempool;
1355extern mempool_t *drbd_ee_mempool;
1356
1357extern struct page *drbd_pp_pool; /* drbd's page pool */
1358extern spinlock_t drbd_pp_lock;
1359extern int drbd_pp_vacant;
1360extern wait_queue_head_t drbd_pp_wait;
1361
1362extern rwlock_t global_state_lock;
1363
1364extern struct drbd_conf *drbd_new_device(unsigned int minor);
1365extern void drbd_free_mdev(struct drbd_conf *mdev);
1366
1367extern int proc_details;
1368
1369/* drbd_req */
1370extern int drbd_make_request_26(struct request_queue *q, struct bio *bio);
1371extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req);
1372extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec);
1373extern int is_valid_ar_handle(struct drbd_request *, sector_t);
1374
1375
1376/* drbd_nl.c */
1377extern void drbd_suspend_io(struct drbd_conf *mdev);
1378extern void drbd_resume_io(struct drbd_conf *mdev);
1379extern char *ppsize(char *buf, unsigned long long size);
1380extern sector_t drbd_new_dev_size(struct drbd_conf *,
1381 struct drbd_backing_dev *);
1382enum determine_dev_size { dev_size_error = -1, unchanged = 0, shrunk = 1, grew = 2 };
1383extern enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *) __must_hold(local);
1384extern void resync_after_online_grow(struct drbd_conf *);
1385extern void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int) __must_hold(local);
1386extern int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role,
1387 int force);
1388enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev);
1389extern int drbd_khelper(struct drbd_conf *mdev, char *cmd);
1390
1391/* drbd_worker.c */
1392extern int drbd_worker(struct drbd_thread *thi);
1393extern int drbd_alter_sa(struct drbd_conf *mdev, int na);
1394extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side);
1395extern void resume_next_sg(struct drbd_conf *mdev);
1396extern void suspend_other_sg(struct drbd_conf *mdev);
1397extern int drbd_resync_finished(struct drbd_conf *mdev);
1398/* maybe rather drbd_main.c ? */
1399extern int drbd_md_sync_page_io(struct drbd_conf *mdev,
1400 struct drbd_backing_dev *bdev, sector_t sector, int rw);
1401extern void drbd_ov_oos_found(struct drbd_conf*, sector_t, int);
1402
1403static inline void ov_oos_print(struct drbd_conf *mdev)
1404{
1405 if (mdev->ov_last_oos_size) {
1406 dev_err(DEV, "Out of sync: start=%llu, size=%lu (sectors)\n",
1407 (unsigned long long)mdev->ov_last_oos_start,
1408 (unsigned long)mdev->ov_last_oos_size);
1409 }
1410 mdev->ov_last_oos_size=0;
1411}
1412
1413
1414extern void drbd_csum(struct drbd_conf *, struct crypto_hash *, struct bio *, void *);
1415/* worker callbacks */
1416extern int w_req_cancel_conflict(struct drbd_conf *, struct drbd_work *, int);
1417extern int w_read_retry_remote(struct drbd_conf *, struct drbd_work *, int);
1418extern int w_e_end_data_req(struct drbd_conf *, struct drbd_work *, int);
1419extern int w_e_end_rsdata_req(struct drbd_conf *, struct drbd_work *, int);
1420extern int w_e_end_csum_rs_req(struct drbd_conf *, struct drbd_work *, int);
1421extern int w_e_end_ov_reply(struct drbd_conf *, struct drbd_work *, int);
1422extern int w_e_end_ov_req(struct drbd_conf *, struct drbd_work *, int);
1423extern int w_ov_finished(struct drbd_conf *, struct drbd_work *, int);
1424extern int w_resync_inactive(struct drbd_conf *, struct drbd_work *, int);
1425extern int w_resume_next_sg(struct drbd_conf *, struct drbd_work *, int);
1426extern int w_io_error(struct drbd_conf *, struct drbd_work *, int);
1427extern int w_send_write_hint(struct drbd_conf *, struct drbd_work *, int);
1428extern int w_make_resync_request(struct drbd_conf *, struct drbd_work *, int);
1429extern int w_send_dblock(struct drbd_conf *, struct drbd_work *, int);
1430extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int);
1431extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int);
1432extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int);
1433extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int);
1434
1435extern void resync_timer_fn(unsigned long data);
1436
1437/* drbd_receiver.c */
1438extern int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list);
1439extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev,
1440 u64 id,
1441 sector_t sector,
1442 unsigned int data_size,
1443 gfp_t gfp_mask) __must_hold(local);
1444extern void drbd_free_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e);
1445extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev,
1446 struct list_head *head);
1447extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev,
1448 struct list_head *head);
1449extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled);
1450extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed);
1451extern void drbd_flush_workqueue(struct drbd_conf *mdev);
1452
1453/* yes, there is kernel_setsockopt, but only since 2.6.18. we don't need to
1454 * mess with get_fs/set_fs, we know we are KERNEL_DS always. */
1455static inline int drbd_setsockopt(struct socket *sock, int level, int optname,
1456 char __user *optval, int optlen)
1457{
1458 int err;
1459 if (level == SOL_SOCKET)
1460 err = sock_setsockopt(sock, level, optname, optval, optlen);
1461 else
1462 err = sock->ops->setsockopt(sock, level, optname, optval,
1463 optlen);
1464 return err;
1465}
1466
1467static inline void drbd_tcp_cork(struct socket *sock)
1468{
1469 int __user val = 1;
1470 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
1471 (char __user *)&val, sizeof(val));
1472}
1473
1474static inline void drbd_tcp_uncork(struct socket *sock)
1475{
1476 int __user val = 0;
1477 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
1478 (char __user *)&val, sizeof(val));
1479}
1480
1481static inline void drbd_tcp_nodelay(struct socket *sock)
1482{
1483 int __user val = 1;
1484 (void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY,
1485 (char __user *)&val, sizeof(val));
1486}
1487
1488static inline void drbd_tcp_quickack(struct socket *sock)
1489{
1490 int __user val = 1;
1491 (void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK,
1492 (char __user *)&val, sizeof(val));
1493}
1494
1495void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo);
1496
1497/* drbd_proc.c */
1498extern struct proc_dir_entry *drbd_proc;
1499extern struct file_operations drbd_proc_fops;
1500extern const char *drbd_conn_str(enum drbd_conns s);
1501extern const char *drbd_role_str(enum drbd_role s);
1502
1503/* drbd_actlog.c */
1504extern void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector);
1505extern void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector);
1506extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector);
1507extern int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector);
1508extern int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector);
1509extern void drbd_rs_cancel_all(struct drbd_conf *mdev);
1510extern int drbd_rs_del_all(struct drbd_conf *mdev);
1511extern void drbd_rs_failed_io(struct drbd_conf *mdev,
1512 sector_t sector, int size);
1513extern int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *);
1514extern void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector,
1515 int size, const char *file, const unsigned int line);
1516#define drbd_set_in_sync(mdev, sector, size) \
1517 __drbd_set_in_sync(mdev, sector, size, __FILE__, __LINE__)
1518extern void __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector,
1519 int size, const char *file, const unsigned int line);
1520#define drbd_set_out_of_sync(mdev, sector, size) \
1521 __drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__)
1522extern void drbd_al_apply_to_bm(struct drbd_conf *mdev);
1523extern void drbd_al_to_on_disk_bm(struct drbd_conf *mdev);
1524extern void drbd_al_shrink(struct drbd_conf *mdev);
1525
1526
1527/* drbd_nl.c */
1528
1529void drbd_nl_cleanup(void);
1530int __init drbd_nl_init(void);
1531void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state);
1532void drbd_bcast_sync_progress(struct drbd_conf *mdev);
1533void drbd_bcast_ee(struct drbd_conf *mdev,
1534 const char *reason, const int dgs,
1535 const char* seen_hash, const char* calc_hash,
1536 const struct drbd_epoch_entry* e);
1537
1538
1539/**
1540 * DOC: DRBD State macros
1541 *
1542 * These macros are used to express state changes in easily readable form.
1543 *
1544 * The NS macros expand to a mask and a value, that can be bit ored onto the
1545 * current state as soon as the spinlock (req_lock) was taken.
1546 *
1547 * The _NS macros are used for state functions that get called with the
1548 * spinlock. These macros expand directly to the new state value.
1549 *
1550 * Besides the basic forms NS() and _NS() additional _?NS[23] are defined
1551 * to express state changes that affect more than one aspect of the state.
1552 *
1553 * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY)
1554 * Means that the network connection was established and that the peer
1555 * is in secondary role.
1556 */
1557#define role_MASK R_MASK
1558#define peer_MASK R_MASK
1559#define disk_MASK D_MASK
1560#define pdsk_MASK D_MASK
1561#define conn_MASK C_MASK
1562#define susp_MASK 1
1563#define user_isp_MASK 1
1564#define aftr_isp_MASK 1
1565
1566#define NS(T, S) \
1567 ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \
1568 ({ union drbd_state val; val.i = 0; val.T = (S); val; })
1569#define NS2(T1, S1, T2, S2) \
1570 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
1571 mask.T2 = T2##_MASK; mask; }), \
1572 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \
1573 val.T2 = (S2); val; })
1574#define NS3(T1, S1, T2, S2, T3, S3) \
1575 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
1576 mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \
1577 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \
1578 val.T2 = (S2); val.T3 = (S3); val; })
1579
1580#define _NS(D, T, S) \
1581 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; })
1582#define _NS2(D, T1, S1, T2, S2) \
1583 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
1584 __ns.T2 = (S2); __ns; })
1585#define _NS3(D, T1, S1, T2, S2, T3, S3) \
1586 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
1587 __ns.T2 = (S2); __ns.T3 = (S3); __ns; })
1588
1589/*
1590 * inline helper functions
1591 *************************/
1592
1593static inline void drbd_state_lock(struct drbd_conf *mdev)
1594{
1595 wait_event(mdev->misc_wait,
1596 !test_and_set_bit(CLUSTER_ST_CHANGE, &mdev->flags));
1597}
1598
1599static inline void drbd_state_unlock(struct drbd_conf *mdev)
1600{
1601 clear_bit(CLUSTER_ST_CHANGE, &mdev->flags);
1602 wake_up(&mdev->misc_wait);
1603}
1604
1605static inline int _drbd_set_state(struct drbd_conf *mdev,
1606 union drbd_state ns, enum chg_state_flags flags,
1607 struct completion *done)
1608{
1609 int rv;
1610
1611 read_lock(&global_state_lock);
1612 rv = __drbd_set_state(mdev, ns, flags, done);
1613 read_unlock(&global_state_lock);
1614
1615 return rv;
1616}
1617
1618/**
1619 * drbd_request_state() - Reqest a state change
1620 * @mdev: DRBD device.
1621 * @mask: mask of state bits to change.
1622 * @val: value of new state bits.
1623 *
1624 * This is the most graceful way of requesting a state change. It is verbose
1625 * quite verbose in case the state change is not possible, and all those
1626 * state changes are globally serialized.
1627 */
1628static inline int drbd_request_state(struct drbd_conf *mdev,
1629 union drbd_state mask,
1630 union drbd_state val)
1631{
1632 return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED);
1633}
1634
1635#define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__)
1636static inline void __drbd_chk_io_error_(struct drbd_conf *mdev, int forcedetach, const char *where)
1637{
1638 switch (mdev->ldev->dc.on_io_error) {
1639 case EP_PASS_ON:
1640 if (!forcedetach) {
1641 if (printk_ratelimit())
1642 dev_err(DEV, "Local IO failed in %s."
1643 "Passing error on...\n", where);
1644 break;
1645 }
1646 /* NOTE fall through to detach case if forcedetach set */
1647 case EP_DETACH:
1648 case EP_CALL_HELPER:
1649 if (mdev->state.disk > D_FAILED) {
1650 _drbd_set_state(_NS(mdev, disk, D_FAILED), CS_HARD, NULL);
1651 dev_err(DEV, "Local IO failed in %s."
1652 "Detaching...\n", where);
1653 }
1654 break;
1655 }
1656}
1657
1658/**
1659 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers
1660 * @mdev: DRBD device.
1661 * @error: Error code passed to the IO completion callback
1662 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data
1663 *
1664 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED)
1665 */
1666#define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__)
1667static inline void drbd_chk_io_error_(struct drbd_conf *mdev,
1668 int error, int forcedetach, const char *where)
1669{
1670 if (error) {
1671 unsigned long flags;
1672 spin_lock_irqsave(&mdev->req_lock, flags);
1673 __drbd_chk_io_error_(mdev, forcedetach, where);
1674 spin_unlock_irqrestore(&mdev->req_lock, flags);
1675 }
1676}
1677
1678
1679/**
1680 * drbd_md_first_sector() - Returns the first sector number of the meta data area
1681 * @bdev: Meta data block device.
1682 *
1683 * BTW, for internal meta data, this happens to be the maximum capacity
1684 * we could agree upon with our peer node.
1685 */
1686static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev)
1687{
1688 switch (bdev->dc.meta_dev_idx) {
1689 case DRBD_MD_INDEX_INTERNAL:
1690 case DRBD_MD_INDEX_FLEX_INT:
1691 return bdev->md.md_offset + bdev->md.bm_offset;
1692 case DRBD_MD_INDEX_FLEX_EXT:
1693 default:
1694 return bdev->md.md_offset;
1695 }
1696}
1697
1698/**
1699 * drbd_md_last_sector() - Return the last sector number of the meta data area
1700 * @bdev: Meta data block device.
1701 */
1702static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev)
1703{
1704 switch (bdev->dc.meta_dev_idx) {
1705 case DRBD_MD_INDEX_INTERNAL:
1706 case DRBD_MD_INDEX_FLEX_INT:
1707 return bdev->md.md_offset + MD_AL_OFFSET - 1;
1708 case DRBD_MD_INDEX_FLEX_EXT:
1709 default:
1710 return bdev->md.md_offset + bdev->md.md_size_sect;
1711 }
1712}
1713
1714/* Returns the number of 512 byte sectors of the device */
1715static inline sector_t drbd_get_capacity(struct block_device *bdev)
1716{
1717 /* return bdev ? get_capacity(bdev->bd_disk) : 0; */
1718 return bdev ? bdev->bd_inode->i_size >> 9 : 0;
1719}
1720
1721/**
1722 * drbd_get_max_capacity() - Returns the capacity we announce to out peer
1723 * @bdev: Meta data block device.
1724 *
1725 * returns the capacity we announce to out peer. we clip ourselves at the
1726 * various MAX_SECTORS, because if we don't, current implementation will
1727 * oops sooner or later
1728 */
1729static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev)
1730{
1731 sector_t s;
1732 switch (bdev->dc.meta_dev_idx) {
1733 case DRBD_MD_INDEX_INTERNAL:
1734 case DRBD_MD_INDEX_FLEX_INT:
1735 s = drbd_get_capacity(bdev->backing_bdev)
1736 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX,
1737 drbd_md_first_sector(bdev))
1738 : 0;
1739 break;
1740 case DRBD_MD_INDEX_FLEX_EXT:
1741 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX,
1742 drbd_get_capacity(bdev->backing_bdev));
1743 /* clip at maximum size the meta device can support */
1744 s = min_t(sector_t, s,
1745 BM_EXT_TO_SECT(bdev->md.md_size_sect
1746 - bdev->md.bm_offset));
1747 break;
1748 default:
1749 s = min_t(sector_t, DRBD_MAX_SECTORS,
1750 drbd_get_capacity(bdev->backing_bdev));
1751 }
1752 return s;
1753}
1754
1755/**
1756 * drbd_md_ss__() - Return the sector number of our meta data super block
1757 * @mdev: DRBD device.
1758 * @bdev: Meta data block device.
1759 */
1760static inline sector_t drbd_md_ss__(struct drbd_conf *mdev,
1761 struct drbd_backing_dev *bdev)
1762{
1763 switch (bdev->dc.meta_dev_idx) {
1764 default: /* external, some index */
1765 return MD_RESERVED_SECT * bdev->dc.meta_dev_idx;
1766 case DRBD_MD_INDEX_INTERNAL:
1767 /* with drbd08, internal meta data is always "flexible" */
1768 case DRBD_MD_INDEX_FLEX_INT:
1769 /* sizeof(struct md_on_disk_07) == 4k
1770 * position: last 4k aligned block of 4k size */
1771 if (!bdev->backing_bdev) {
1772 if (__ratelimit(&drbd_ratelimit_state)) {
1773 dev_err(DEV, "bdev->backing_bdev==NULL\n");
1774 dump_stack();
1775 }
1776 return 0;
1777 }
1778 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL)
1779 - MD_AL_OFFSET;
1780 case DRBD_MD_INDEX_FLEX_EXT:
1781 return 0;
1782 }
1783}
1784
1785static inline void
1786_drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w)
1787{
1788 list_add_tail(&w->list, &q->q);
1789 up(&q->s);
1790}
1791
1792static inline void
1793drbd_queue_work_front(struct drbd_work_queue *q, struct drbd_work *w)
1794{
1795 unsigned long flags;
1796 spin_lock_irqsave(&q->q_lock, flags);
1797 list_add(&w->list, &q->q);
1798 up(&q->s); /* within the spinlock,
1799 see comment near end of drbd_worker() */
1800 spin_unlock_irqrestore(&q->q_lock, flags);
1801}
1802
1803static inline void
1804drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w)
1805{
1806 unsigned long flags;
1807 spin_lock_irqsave(&q->q_lock, flags);
1808 list_add_tail(&w->list, &q->q);
1809 up(&q->s); /* within the spinlock,
1810 see comment near end of drbd_worker() */
1811 spin_unlock_irqrestore(&q->q_lock, flags);
1812}
1813
1814static inline void wake_asender(struct drbd_conf *mdev)
1815{
1816 if (test_bit(SIGNAL_ASENDER, &mdev->flags))
1817 force_sig(DRBD_SIG, mdev->asender.task);
1818}
1819
1820static inline void request_ping(struct drbd_conf *mdev)
1821{
1822 set_bit(SEND_PING, &mdev->flags);
1823 wake_asender(mdev);
1824}
1825
1826static inline int drbd_send_short_cmd(struct drbd_conf *mdev,
1827 enum drbd_packets cmd)
1828{
1829 struct p_header h;
1830 return drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, &h, sizeof(h));
1831}
1832
1833static inline int drbd_send_ping(struct drbd_conf *mdev)
1834{
1835 struct p_header h;
1836 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING, &h, sizeof(h));
1837}
1838
1839static inline int drbd_send_ping_ack(struct drbd_conf *mdev)
1840{
1841 struct p_header h;
1842 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING_ACK, &h, sizeof(h));
1843}
1844
1845static inline void drbd_thread_stop(struct drbd_thread *thi)
1846{
1847 _drbd_thread_stop(thi, FALSE, TRUE);
1848}
1849
1850static inline void drbd_thread_stop_nowait(struct drbd_thread *thi)
1851{
1852 _drbd_thread_stop(thi, FALSE, FALSE);
1853}
1854
1855static inline void drbd_thread_restart_nowait(struct drbd_thread *thi)
1856{
1857 _drbd_thread_stop(thi, TRUE, FALSE);
1858}
1859
1860/* counts how many answer packets packets we expect from our peer,
1861 * for either explicit application requests,
1862 * or implicit barrier packets as necessary.
1863 * increased:
1864 * w_send_barrier
1865 * _req_mod(req, queue_for_net_write or queue_for_net_read);
1866 * it is much easier and equally valid to count what we queue for the
1867 * worker, even before it actually was queued or send.
1868 * (drbd_make_request_common; recovery path on read io-error)
1869 * decreased:
1870 * got_BarrierAck (respective tl_clear, tl_clear_barrier)
1871 * _req_mod(req, data_received)
1872 * [from receive_DataReply]
1873 * _req_mod(req, write_acked_by_peer or recv_acked_by_peer or neg_acked)
1874 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)]
1875 * for some reason it is NOT decreased in got_NegAck,
1876 * but in the resulting cleanup code from report_params.
1877 * we should try to remember the reason for that...
1878 * _req_mod(req, send_failed or send_canceled)
1879 * _req_mod(req, connection_lost_while_pending)
1880 * [from tl_clear_barrier]
1881 */
1882static inline void inc_ap_pending(struct drbd_conf *mdev)
1883{
1884 atomic_inc(&mdev->ap_pending_cnt);
1885}
1886
1887#define ERR_IF_CNT_IS_NEGATIVE(which) \
1888 if (atomic_read(&mdev->which) < 0) \
1889 dev_err(DEV, "in %s:%d: " #which " = %d < 0 !\n", \
1890 __func__ , __LINE__ , \
1891 atomic_read(&mdev->which))
1892
1893#define dec_ap_pending(mdev) do { \
1894 typecheck(struct drbd_conf *, mdev); \
1895 if (atomic_dec_and_test(&mdev->ap_pending_cnt)) \
1896 wake_up(&mdev->misc_wait); \
1897 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt); } while (0)
1898
1899/* counts how many resync-related answers we still expect from the peer
1900 * increase decrease
1901 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY)
1902 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK whith ID_SYNCER)
1903 * (or P_NEG_ACK with ID_SYNCER)
1904 */
1905static inline void inc_rs_pending(struct drbd_conf *mdev)
1906{
1907 atomic_inc(&mdev->rs_pending_cnt);
1908}
1909
1910#define dec_rs_pending(mdev) do { \
1911 typecheck(struct drbd_conf *, mdev); \
1912 atomic_dec(&mdev->rs_pending_cnt); \
1913 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt); } while (0)
1914
1915/* counts how many answers we still need to send to the peer.
1916 * increased on
1917 * receive_Data unless protocol A;
1918 * we need to send a P_RECV_ACK (proto B)
1919 * or P_WRITE_ACK (proto C)
1920 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK
1921 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA
1922 * receive_Barrier_* we need to send a P_BARRIER_ACK
1923 */
1924static inline void inc_unacked(struct drbd_conf *mdev)
1925{
1926 atomic_inc(&mdev->unacked_cnt);
1927}
1928
1929#define dec_unacked(mdev) do { \
1930 typecheck(struct drbd_conf *, mdev); \
1931 atomic_dec(&mdev->unacked_cnt); \
1932 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0)
1933
1934#define sub_unacked(mdev, n) do { \
1935 typecheck(struct drbd_conf *, mdev); \
1936 atomic_sub(n, &mdev->unacked_cnt); \
1937 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0)
1938
1939
1940static inline void put_net_conf(struct drbd_conf *mdev)
1941{
1942 if (atomic_dec_and_test(&mdev->net_cnt))
1943 wake_up(&mdev->misc_wait);
1944}
1945
1946/**
1947 * get_net_conf() - Increase ref count on mdev->net_conf; Returns 0 if nothing there
1948 * @mdev: DRBD device.
1949 *
1950 * You have to call put_net_conf() when finished working with mdev->net_conf.
1951 */
1952static inline int get_net_conf(struct drbd_conf *mdev)
1953{
1954 int have_net_conf;
1955
1956 atomic_inc(&mdev->net_cnt);
1957 have_net_conf = mdev->state.conn >= C_UNCONNECTED;
1958 if (!have_net_conf)
1959 put_net_conf(mdev);
1960 return have_net_conf;
1961}
1962
1963/**
1964 * get_ldev() - Increase the ref count on mdev->ldev. Returns 0 if there is no ldev
1965 * @M: DRBD device.
1966 *
1967 * You have to call put_ldev() when finished working with mdev->ldev.
1968 */
1969#define get_ldev(M) __cond_lock(local, _get_ldev_if_state(M,D_INCONSISTENT))
1970#define get_ldev_if_state(M,MINS) __cond_lock(local, _get_ldev_if_state(M,MINS))
1971
1972static inline void put_ldev(struct drbd_conf *mdev)
1973{
1974 __release(local);
1975 if (atomic_dec_and_test(&mdev->local_cnt))
1976 wake_up(&mdev->misc_wait);
1977 D_ASSERT(atomic_read(&mdev->local_cnt) >= 0);
1978}
1979
1980#ifndef __CHECKER__
1981static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
1982{
1983 int io_allowed;
1984
1985 atomic_inc(&mdev->local_cnt);
1986 io_allowed = (mdev->state.disk >= mins);
1987 if (!io_allowed)
1988 put_ldev(mdev);
1989 return io_allowed;
1990}
1991#else
1992extern int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins);
1993#endif
1994
1995/* you must have an "get_ldev" reference */
1996static inline void drbd_get_syncer_progress(struct drbd_conf *mdev,
1997 unsigned long *bits_left, unsigned int *per_mil_done)
1998{
1999 /*
2000 * this is to break it at compile time when we change that
2001 * (we may feel 4TB maximum storage per drbd is not enough)
2002 */
2003 typecheck(unsigned long, mdev->rs_total);
2004
2005 /* note: both rs_total and rs_left are in bits, i.e. in
2006 * units of BM_BLOCK_SIZE.
2007 * for the percentage, we don't care. */
2008
2009 *bits_left = drbd_bm_total_weight(mdev) - mdev->rs_failed;
2010 /* >> 10 to prevent overflow,
2011 * +1 to prevent division by zero */
2012 if (*bits_left > mdev->rs_total) {
2013 /* doh. maybe a logic bug somewhere.
2014 * may also be just a race condition
2015 * between this and a disconnect during sync.
2016 * for now, just prevent in-kernel buffer overflow.
2017 */
2018 smp_rmb();
2019 dev_warn(DEV, "cs:%s rs_left=%lu > rs_total=%lu (rs_failed %lu)\n",
2020 drbd_conn_str(mdev->state.conn),
2021 *bits_left, mdev->rs_total, mdev->rs_failed);
2022 *per_mil_done = 0;
2023 } else {
2024 /* make sure the calculation happens in long context */
2025 unsigned long tmp = 1000UL -
2026 (*bits_left >> 10)*1000UL
2027 / ((mdev->rs_total >> 10) + 1UL);
2028 *per_mil_done = tmp;
2029 }
2030}
2031
2032
2033/* this throttles on-the-fly application requests
2034 * according to max_buffers settings;
2035 * maybe re-implement using semaphores? */
2036static inline int drbd_get_max_buffers(struct drbd_conf *mdev)
2037{
2038 int mxb = 1000000; /* arbitrary limit on open requests */
2039 if (get_net_conf(mdev)) {
2040 mxb = mdev->net_conf->max_buffers;
2041 put_net_conf(mdev);
2042 }
2043 return mxb;
2044}
2045
2046static inline int drbd_state_is_stable(union drbd_state s)
2047{
2048
2049 /* DO NOT add a default clause, we want the compiler to warn us
2050 * for any newly introduced state we may have forgotten to add here */
2051
2052 switch ((enum drbd_conns)s.conn) {
2053 /* new io only accepted when there is no connection, ... */
2054 case C_STANDALONE:
2055 case C_WF_CONNECTION:
2056 /* ... or there is a well established connection. */
2057 case C_CONNECTED:
2058 case C_SYNC_SOURCE:
2059 case C_SYNC_TARGET:
2060 case C_VERIFY_S:
2061 case C_VERIFY_T:
2062 case C_PAUSED_SYNC_S:
2063 case C_PAUSED_SYNC_T:
2064 /* maybe stable, look at the disk state */
2065 break;
2066
2067 /* no new io accepted during tansitional states
2068 * like handshake or teardown */
2069 case C_DISCONNECTING:
2070 case C_UNCONNECTED:
2071 case C_TIMEOUT:
2072 case C_BROKEN_PIPE:
2073 case C_NETWORK_FAILURE:
2074 case C_PROTOCOL_ERROR:
2075 case C_TEAR_DOWN:
2076 case C_WF_REPORT_PARAMS:
2077 case C_STARTING_SYNC_S:
2078 case C_STARTING_SYNC_T:
2079 case C_WF_BITMAP_S:
2080 case C_WF_BITMAP_T:
2081 case C_WF_SYNC_UUID:
2082 case C_MASK:
2083 /* not "stable" */
2084 return 0;
2085 }
2086
2087 switch ((enum drbd_disk_state)s.disk) {
2088 case D_DISKLESS:
2089 case D_INCONSISTENT:
2090 case D_OUTDATED:
2091 case D_CONSISTENT:
2092 case D_UP_TO_DATE:
2093 /* disk state is stable as well. */
2094 break;
2095
2096 /* no new io accepted during tansitional states */
2097 case D_ATTACHING:
2098 case D_FAILED:
2099 case D_NEGOTIATING:
2100 case D_UNKNOWN:
2101 case D_MASK:
2102 /* not "stable" */
2103 return 0;
2104 }
2105
2106 return 1;
2107}
2108
2109static inline int __inc_ap_bio_cond(struct drbd_conf *mdev)
2110{
2111 int mxb = drbd_get_max_buffers(mdev);
2112
2113 if (mdev->state.susp)
2114 return 0;
2115 if (test_bit(SUSPEND_IO, &mdev->flags))
2116 return 0;
2117
2118 /* to avoid potential deadlock or bitmap corruption,
2119 * in various places, we only allow new application io
2120 * to start during "stable" states. */
2121
2122 /* no new io accepted when attaching or detaching the disk */
2123 if (!drbd_state_is_stable(mdev->state))
2124 return 0;
2125
2126 /* since some older kernels don't have atomic_add_unless,
2127 * and we are within the spinlock anyways, we have this workaround. */
2128 if (atomic_read(&mdev->ap_bio_cnt) > mxb)
2129 return 0;
2130 if (test_bit(BITMAP_IO, &mdev->flags))
2131 return 0;
2132 return 1;
2133}
2134
2135/* I'd like to use wait_event_lock_irq,
2136 * but I'm not sure when it got introduced,
2137 * and not sure when it has 3 or 4 arguments */
2138static inline void inc_ap_bio(struct drbd_conf *mdev, int one_or_two)
2139{
2140 /* compare with after_state_ch,
2141 * os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S */
2142 DEFINE_WAIT(wait);
2143
2144 /* we wait here
2145 * as long as the device is suspended
2146 * until the bitmap is no longer on the fly during connection
2147 * handshake as long as we would exeed the max_buffer limit.
2148 *
2149 * to avoid races with the reconnect code,
2150 * we need to atomic_inc within the spinlock. */
2151
2152 spin_lock_irq(&mdev->req_lock);
2153 while (!__inc_ap_bio_cond(mdev)) {
2154 prepare_to_wait(&mdev->misc_wait, &wait, TASK_UNINTERRUPTIBLE);
2155 spin_unlock_irq(&mdev->req_lock);
2156 schedule();
2157 finish_wait(&mdev->misc_wait, &wait);
2158 spin_lock_irq(&mdev->req_lock);
2159 }
2160 atomic_add(one_or_two, &mdev->ap_bio_cnt);
2161 spin_unlock_irq(&mdev->req_lock);
2162}
2163
2164static inline void dec_ap_bio(struct drbd_conf *mdev)
2165{
2166 int mxb = drbd_get_max_buffers(mdev);
2167 int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt);
2168
2169 D_ASSERT(ap_bio >= 0);
2170 /* this currently does wake_up for every dec_ap_bio!
2171 * maybe rather introduce some type of hysteresis?
2172 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */
2173 if (ap_bio < mxb)
2174 wake_up(&mdev->misc_wait);
2175 if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) {
2176 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
2177 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
2178 }
2179}
2180
2181static inline void drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val)
2182{
2183 mdev->ed_uuid = val;
2184}
2185
2186static inline int seq_cmp(u32 a, u32 b)
2187{
2188 /* we assume wrap around at 32bit.
2189 * for wrap around at 24bit (old atomic_t),
2190 * we'd have to
2191 * a <<= 8; b <<= 8;
2192 */
2193 return (s32)(a) - (s32)(b);
2194}
2195#define seq_lt(a, b) (seq_cmp((a), (b)) < 0)
2196#define seq_gt(a, b) (seq_cmp((a), (b)) > 0)
2197#define seq_ge(a, b) (seq_cmp((a), (b)) >= 0)
2198#define seq_le(a, b) (seq_cmp((a), (b)) <= 0)
2199/* CAUTION: please no side effects in arguments! */
2200#define seq_max(a, b) ((u32)(seq_gt((a), (b)) ? (a) : (b)))
2201
2202static inline void update_peer_seq(struct drbd_conf *mdev, unsigned int new_seq)
2203{
2204 unsigned int m;
2205 spin_lock(&mdev->peer_seq_lock);
2206 m = seq_max(mdev->peer_seq, new_seq);
2207 mdev->peer_seq = m;
2208 spin_unlock(&mdev->peer_seq_lock);
2209 if (m == new_seq)
2210 wake_up(&mdev->seq_wait);
2211}
2212
2213static inline void drbd_update_congested(struct drbd_conf *mdev)
2214{
2215 struct sock *sk = mdev->data.socket->sk;
2216 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5)
2217 set_bit(NET_CONGESTED, &mdev->flags);
2218}
2219
2220static inline int drbd_queue_order_type(struct drbd_conf *mdev)
2221{
2222 /* sorry, we currently have no working implementation
2223 * of distributed TCQ stuff */
2224#ifndef QUEUE_ORDERED_NONE
2225#define QUEUE_ORDERED_NONE 0
2226#endif
2227 return QUEUE_ORDERED_NONE;
2228}
2229
2230static inline void drbd_blk_run_queue(struct request_queue *q)
2231{
2232 if (q && q->unplug_fn)
2233 q->unplug_fn(q);
2234}
2235
2236static inline void drbd_kick_lo(struct drbd_conf *mdev)
2237{
2238 if (get_ldev(mdev)) {
2239 drbd_blk_run_queue(bdev_get_queue(mdev->ldev->backing_bdev));
2240 put_ldev(mdev);
2241 }
2242}
2243
2244static inline void drbd_md_flush(struct drbd_conf *mdev)
2245{
2246 int r;
2247
2248 if (test_bit(MD_NO_BARRIER, &mdev->flags))
2249 return;
2250
2251 r = blkdev_issue_flush(mdev->ldev->md_bdev, NULL);
2252 if (r) {
2253 set_bit(MD_NO_BARRIER, &mdev->flags);
2254 dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r);
2255 }
2256}
2257
2258#endif
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