4 This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
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>.
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)
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.
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.
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>
44 #include <linux/lru_cache.h>
47 # define __protected_by(x) __attribute__((require_context(x,1,999,"rdwr")))
48 # define __protected_read_by(x) __attribute__((require_context(x,1,999,"read")))
49 # define __protected_write_by(x) __attribute__((require_context(x,1,999,"write")))
50 # define __must_hold(x) __attribute__((context(x,1,1), require_context(x,1,999,"call")))
52 # define __protected_by(x)
53 # define __protected_read_by(x)
54 # define __protected_write_by(x)
55 # define __must_hold(x)
58 #define __no_warn(lock, stmt) do { __acquire(lock); stmt; __release(lock); } while (0)
60 /* module parameter, defined in drbd_main.c */
61 extern unsigned int minor_count;
62 extern int disable_sendpage;
64 extern unsigned int cn_idx;
66 #ifdef CONFIG_DRBD_FAULT_INJECTION
67 extern int enable_faults;
68 extern int fault_rate;
69 extern int fault_devs;
72 extern char usermode_helper[];
82 /* I don't remember why XCPU ...
83 * This is used to wake the asender,
84 * and to interrupt sending the sending task
87 #define DRBD_SIG SIGXCPU
89 /* This is used to stop/restart our threads.
90 * Cannot use SIGTERM nor SIGKILL, since these
91 * are sent out by init on runlevel changes
92 * I choose SIGHUP for now.
94 #define DRBD_SIGKILL SIGHUP
96 /* All EEs on the free list should have ID_VACANT (== 0)
97 * freshly allocated EEs get !ID_VACANT (== 1)
98 * so if it says "cannot dereference null pointer at address 0x00000001",
99 * it is most likely one of these :( */
101 #define ID_IN_SYNC (4711ULL)
102 #define ID_OUT_OF_SYNC (4712ULL)
104 #define ID_SYNCER (-1ULL)
106 #define is_syncer_block_id(id) ((id) == ID_SYNCER)
111 /* to shorten dev_warn(DEV, "msg"); and relatives statements */
112 #define DEV (disk_to_dev(mdev->vdisk))
114 #define D_ASSERT(exp) if (!(exp)) \
115 dev_err(DEV, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__)
117 #define ERR_IF(exp) if (({ \
118 int _b = (exp) != 0; \
119 if (_b) dev_err(DEV, "%s: (%s) in %s:%d\n", \
120 __func__, #exp, __FILE__, __LINE__); \
124 /* Defines to control fault insertion */
126 DRBD_FAULT_MD_WR = 0, /* meta data write */
127 DRBD_FAULT_MD_RD = 1, /* read */
128 DRBD_FAULT_RS_WR = 2, /* resync */
129 DRBD_FAULT_RS_RD = 3,
130 DRBD_FAULT_DT_WR = 4, /* data */
131 DRBD_FAULT_DT_RD = 5,
132 DRBD_FAULT_DT_RA = 6, /* data read ahead */
133 DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */
134 DRBD_FAULT_AL_EE = 8, /* alloc ee */
135 DRBD_FAULT_RECEIVE = 9, /* Changes some bytes upon receiving a [rs]data block */
140 #ifdef CONFIG_DRBD_FAULT_INJECTION
142 _drbd_insert_fault(struct drbd_conf *mdev, unsigned int type);
144 drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) {
146 (enable_faults & (1<<type)) &&
147 _drbd_insert_fault(mdev, type);
149 #define FAULT_ACTIVE(_m, _t) (drbd_insert_fault((_m), (_t)))
152 #define FAULT_ACTIVE(_m, _t) (0)
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))
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)
164 extern struct drbd_conf **minor_table;
165 extern struct ratelimit_state drbd_ratelimit_state;
169 /* receiver (data socket) */
171 P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */
172 P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */
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 */
186 P_AUTH_CHALLENGE = 0x10,
187 P_AUTH_RESPONSE = 0x11,
188 P_STATE_CHG_REQ = 0x12,
190 /* asender (meta socket */
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,
203 /* "new" commands, no longer fitting into the ordering scheme above */
205 P_OV_REQUEST = 0x1e, /* data socket */
207 P_OV_RESULT = 0x20, /* meta socket */
208 P_CSUM_RS_REQUEST = 0x21, /* data socket */
209 P_RS_IS_IN_SYNC = 0x22, /* meta socket */
210 P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */
211 P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */
212 /* P_CKPT_FENCE_REQ = 0x25, * currently reserved for protocol D */
213 /* P_CKPT_DISABLE_REQ = 0x26, * currently reserved for protocol D */
214 P_DELAY_PROBE = 0x27, /* is used on BOTH sockets */
217 P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */
218 P_MAX_OPT_CMD = 0x101,
220 /* special command ids for handshake */
222 P_HAND_SHAKE_M = 0xfff1, /* First Packet on the MetaSock */
223 P_HAND_SHAKE_S = 0xfff2, /* First Packet on the Socket */
225 P_HAND_SHAKE = 0xfffe /* FIXED for the next century! */
228 static inline const char *cmdname(enum drbd_packets cmd)
230 /* THINK may need to become several global tables
231 * when we want to support more than
233 static const char *cmdnames[] = {
235 [P_DATA_REPLY] = "DataReply",
236 [P_RS_DATA_REPLY] = "RSDataReply",
237 [P_BARRIER] = "Barrier",
238 [P_BITMAP] = "ReportBitMap",
239 [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget",
240 [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource",
241 [P_UNPLUG_REMOTE] = "UnplugRemote",
242 [P_DATA_REQUEST] = "DataRequest",
243 [P_RS_DATA_REQUEST] = "RSDataRequest",
244 [P_SYNC_PARAM] = "SyncParam",
245 [P_SYNC_PARAM89] = "SyncParam89",
246 [P_PROTOCOL] = "ReportProtocol",
247 [P_UUIDS] = "ReportUUIDs",
248 [P_SIZES] = "ReportSizes",
249 [P_STATE] = "ReportState",
250 [P_SYNC_UUID] = "ReportSyncUUID",
251 [P_AUTH_CHALLENGE] = "AuthChallenge",
252 [P_AUTH_RESPONSE] = "AuthResponse",
254 [P_PING_ACK] = "PingAck",
255 [P_RECV_ACK] = "RecvAck",
256 [P_WRITE_ACK] = "WriteAck",
257 [P_RS_WRITE_ACK] = "RSWriteAck",
258 [P_DISCARD_ACK] = "DiscardAck",
259 [P_NEG_ACK] = "NegAck",
260 [P_NEG_DREPLY] = "NegDReply",
261 [P_NEG_RS_DREPLY] = "NegRSDReply",
262 [P_BARRIER_ACK] = "BarrierAck",
263 [P_STATE_CHG_REQ] = "StateChgRequest",
264 [P_STATE_CHG_REPLY] = "StateChgReply",
265 [P_OV_REQUEST] = "OVRequest",
266 [P_OV_REPLY] = "OVReply",
267 [P_OV_RESULT] = "OVResult",
268 [P_CSUM_RS_REQUEST] = "CsumRSRequest",
269 [P_RS_IS_IN_SYNC] = "CsumRSIsInSync",
270 [P_COMPRESSED_BITMAP] = "CBitmap",
271 [P_DELAY_PROBE] = "DelayProbe",
275 if (cmd == P_HAND_SHAKE_M)
277 if (cmd == P_HAND_SHAKE_S)
279 if (cmd == P_HAND_SHAKE)
281 if (cmd >= P_MAX_CMD)
283 return cmdnames[cmd];
286 /* for sending/receiving the bitmap,
287 * possibly in some encoding scheme */
290 * stores total bits and long words
291 * of the bitmap, so we don't need to
292 * call the accessor functions over and again. */
293 unsigned long bm_bits;
294 unsigned long bm_words;
295 /* during xfer, current position within the bitmap */
296 unsigned long bit_offset;
297 unsigned long word_offset;
299 /* statistics; index: (h->command == P_BITMAP) */
304 extern void INFO_bm_xfer_stats(struct drbd_conf *mdev,
305 const char *direction, struct bm_xfer_ctx *c);
307 static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c)
309 /* word_offset counts "native long words" (32 or 64 bit),
311 * Encoded packet may end at an unaligned bit offset.
312 * In case a fallback clear text packet is transmitted in
313 * between, we adjust this offset back to the last 64bit
314 * aligned "native long word", which makes coding and decoding
315 * the plain text bitmap much more convenient. */
316 #if BITS_PER_LONG == 64
317 c->word_offset = c->bit_offset >> 6;
318 #elif BITS_PER_LONG == 32
319 c->word_offset = c->bit_offset >> 5;
320 c->word_offset &= ~(1UL);
322 # error "unsupported BITS_PER_LONG"
327 #define __packed __attribute__((packed))
330 /* This is the layout for a packet on the wire.
331 * The byteorder is the network byte order.
332 * (except block_id and barrier fields.
333 * these are pointers to local structs
334 * and have no relevance for the partner,
335 * which just echoes them as received.)
337 * NOTE that the payload starts at a long aligned offset,
338 * regardless of 32 or 64 bit arch!
343 u16 length; /* bytes of data after this header */
346 /* 8 bytes. packet FIXED for the next century! */
349 * short commands, packets without payload, plain p_header:
352 * P_BECOME_SYNC_TARGET
353 * P_BECOME_SYNC_SOURCE
358 * commands with out-of-struct payload:
359 * P_BITMAP (no additional fields)
360 * P_DATA, P_DATA_REPLY (see p_data)
361 * P_COMPRESSED_BITMAP (see receive_compressed_bitmap)
364 /* these defines must not be changed without changing the protocol version */
365 #define DP_HARDBARRIER 1
367 #define DP_MAY_SET_IN_SYNC 4
370 struct p_header head;
371 u64 sector; /* 64 bits sector number */
372 u64 block_id; /* to identify the request in protocol B&C */
378 * commands which share a struct:
380 * P_RECV_ACK (proto B), P_WRITE_ACK (proto C),
381 * P_DISCARD_ACK (proto C, two-primaries conflict detection)
383 * P_DATA_REQUEST, P_RS_DATA_REQUEST
386 struct p_header head;
395 struct p_header head;
399 u32 pad; /* to multiple of 8 Byte */
403 * commands with their own struct for additional fields:
412 struct p_header head; /* 8 bytes */
417 /* should be more than enough for future enhancements
418 * for now, feature_flags and the reserverd array shall be zero.
424 /* 80 bytes, FIXED for the next century */
427 struct p_header head;
428 u32 barrier; /* barrier number _handle_ only */
429 u32 pad; /* to multiple of 8 Byte */
432 struct p_barrier_ack {
433 struct p_header head;
439 struct p_header head;
442 /* Since protocol version 88 and higher. */
446 struct p_rs_param_89 {
447 struct p_header head;
449 /* protocol version 89: */
450 char verify_alg[SHARED_SECRET_MAX];
451 char csums_alg[SHARED_SECRET_MAX];
454 enum drbd_conn_flags {
460 struct p_header head;
468 /* Since protocol version 87 and higher. */
469 char integrity_alg[0];
474 struct p_header head;
475 u64 uuid[UI_EXTENDED_SIZE];
479 struct p_header head;
484 struct p_header head;
485 u64 d_size; /* size of disk */
486 u64 u_size; /* user requested size */
487 u64 c_size; /* current exported size */
488 u32 max_segment_size; /* Maximal size of a BIO */
489 u16 queue_order_type; /* not yet implemented in DRBD*/
490 u16 dds_flags; /* use enum dds_flags here. */
494 struct p_header head;
499 struct p_header head;
504 struct p_req_state_reply {
505 struct p_header head;
509 struct p_drbd06_param {
520 struct p_header head;
526 /* Valid values for the encoding field.
527 * Bump proto version when changing this. */
528 enum drbd_bitmap_code {
529 /* RLE_VLI_Bytes = 0,
530 * and other bit variants had been defined during
531 * algorithm evaluation. */
535 struct p_compressed_bm {
536 struct p_header head;
537 /* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code
538 * (encoding & 0x80): polarity (set/unset) of first runlength
539 * ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits
540 * used to pad up to head.length bytes
547 struct p_delay_probe {
548 struct p_header head;
549 u32 seq_num; /* sequence number to match the two probe packets */
550 u32 offset; /* usecs the probe got sent after the reference time point */
554 struct list_head list;
555 unsigned int seq_num;
559 /* DCBP: Drbd Compressed Bitmap Packet ... */
560 static inline enum drbd_bitmap_code
561 DCBP_get_code(struct p_compressed_bm *p)
563 return (enum drbd_bitmap_code)(p->encoding & 0x0f);
567 DCBP_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code)
570 p->encoding = (p->encoding & ~0xf) | code;
574 DCBP_get_start(struct p_compressed_bm *p)
576 return (p->encoding & 0x80) != 0;
580 DCBP_set_start(struct p_compressed_bm *p, int set)
582 p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0);
586 DCBP_get_pad_bits(struct p_compressed_bm *p)
588 return (p->encoding >> 4) & 0x7;
592 DCBP_set_pad_bits(struct p_compressed_bm *p, int n)
595 p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4);
598 /* one bitmap packet, including the p_header,
599 * should fit within one _architecture independend_ page.
600 * so we need to use the fixed size 4KiB page size
601 * most architechtures have used for a long time.
603 #define BM_PACKET_PAYLOAD_BYTES (4096 - sizeof(struct p_header))
604 #define BM_PACKET_WORDS (BM_PACKET_PAYLOAD_BYTES/sizeof(long))
605 #define BM_PACKET_VLI_BYTES_MAX (4096 - sizeof(struct p_compressed_bm))
606 #if (PAGE_SIZE < 4096)
607 /* drbd_send_bitmap / receive_bitmap would break horribly */
608 #error "PAGE_SIZE too small"
612 struct p_header header;
613 struct p_handshake handshake;
615 struct p_block_ack block_ack;
616 struct p_barrier barrier;
617 struct p_barrier_ack barrier_ack;
618 struct p_rs_param_89 rs_param_89;
619 struct p_protocol protocol;
620 struct p_sizes sizes;
621 struct p_uuids uuids;
622 struct p_state state;
623 struct p_req_state req_state;
624 struct p_req_state_reply req_state_reply;
625 struct p_block_req block_req;
628 /**********************************************************************/
629 enum drbd_thread_state {
638 struct task_struct *task;
639 struct completion stop;
640 enum drbd_thread_state t_state;
641 int (*function) (struct drbd_thread *);
642 struct drbd_conf *mdev;
646 static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi)
648 /* THINK testing the t_state seems to be uncritical in all cases
649 * (but thread_{start,stop}), so we can read it *without* the lock.
658 * Having this as the first member of a struct provides sort of "inheritance".
659 * "derived" structs can be "drbd_queue_work()"ed.
660 * The callback should know and cast back to the descendant struct.
661 * drbd_request and drbd_epoch_entry are descendants of drbd_work.
664 typedef int (*drbd_work_cb)(struct drbd_conf *, struct drbd_work *, int cancel);
666 struct list_head list;
670 struct drbd_tl_epoch;
671 struct drbd_request {
673 struct drbd_conf *mdev;
675 /* if local IO is not allowed, will be NULL.
676 * if local IO _is_ allowed, holds the locally submitted bio clone,
677 * or, after local IO completion, the ERR_PTR(error).
678 * see drbd_endio_pri(). */
679 struct bio *private_bio;
681 struct hlist_node colision;
684 unsigned int epoch; /* barrier_nr */
686 /* barrier_nr: used to check on "completion" whether this req was in
687 * the current epoch, and we therefore have to close it,
688 * starting a new epoch...
691 /* up to here, the struct layout is identical to drbd_epoch_entry;
692 * we might be able to use that to our advantage... */
694 struct list_head tl_requests; /* ring list in the transfer log */
695 struct bio *master_bio; /* master bio pointer */
696 unsigned long rq_state; /* see comments above _req_mod() */
698 unsigned long start_time;
701 struct drbd_tl_epoch {
703 struct list_head requests; /* requests before */
704 struct drbd_tl_epoch *next; /* pointer to the next barrier */
705 unsigned int br_number; /* the barriers identifier. */
706 int n_req; /* number of requests attached before this barrier */
711 /* These Tl_epoch_entries may be in one of 6 lists:
712 active_ee .. data packet being written
713 sync_ee .. syncer block being written
714 done_ee .. block written, need to send P_WRITE_ACK
715 read_ee .. [RS]P_DATA_REQUEST being read
719 struct list_head list;
720 unsigned int barrier_nr;
721 atomic_t epoch_size; /* increased on every request added. */
722 atomic_t active; /* increased on every req. added, and dec on every finished. */
726 /* drbd_epoch flag bits */
728 DE_BARRIER_IN_NEXT_EPOCH_ISSUED,
729 DE_BARRIER_IN_NEXT_EPOCH_DONE,
730 DE_CONTAINS_A_BARRIER,
731 DE_HAVE_BARRIER_NUMBER,
740 EV_CLEANUP = 32, /* used as flag */
743 struct drbd_epoch_entry {
745 struct drbd_conf *mdev;
746 struct bio *private_bio;
747 struct hlist_node colision;
751 struct drbd_epoch *epoch;
755 struct drbd_wq_barrier {
757 struct completion done;
767 __EE_CALL_AL_COMPLETE_IO,
768 __EE_CONFLICT_PENDING,
769 __EE_MAY_SET_IN_SYNC,
772 #define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO)
773 #define EE_CONFLICT_PENDING (1<<__EE_CONFLICT_PENDING)
774 #define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC)
775 #define EE_IS_BARRIER (1<<__EE_IS_BARRIER)
777 /* global flag bits */
779 CREATE_BARRIER, /* next P_DATA is preceeded by a P_BARRIER */
780 SIGNAL_ASENDER, /* whether asender wants to be interrupted */
781 SEND_PING, /* whether asender should send a ping asap */
783 STOP_SYNC_TIMER, /* tell timer to cancel itself */
784 UNPLUG_QUEUED, /* only relevant with kernel 2.4 */
785 UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */
786 MD_DIRTY, /* current uuids and flags not yet on disk */
787 DISCARD_CONCURRENT, /* Set on one node, cleared on the peer! */
788 USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */
789 CLUSTER_ST_CHANGE, /* Cluster wide state change going on... */
792 CRASHED_PRIMARY, /* This node was a crashed primary.
793 * Gets cleared when the state.conn
794 * goes into C_CONNECTED state. */
795 WRITE_BM_AFTER_RESYNC, /* A kmalloc() during resync failed */
796 NO_BARRIER_SUPP, /* underlying block device doesn't implement barriers */
799 MD_NO_BARRIER, /* meta data device does not support barriers,
801 SUSPEND_IO, /* suspend application io */
802 BITMAP_IO, /* suspend application io;
803 once no more io in flight, start bitmap io */
804 BITMAP_IO_QUEUED, /* Started bitmap IO */
805 RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */
806 NET_CONGESTED, /* The data socket is congested */
808 CONFIG_PENDING, /* serialization of (re)configuration requests.
809 * if set, also prevents the device from dying */
810 DEVICE_DYING, /* device became unconfigured,
811 * but worker thread is still handling the cleanup.
812 * reconfiguring (nl_disk_conf, nl_net_conf) is dissalowed,
813 * while this is set. */
814 RESIZE_PENDING, /* Size change detected locally, waiting for the response from
815 * the peer, if it changed there as well. */
816 CONN_DRY_RUN, /* Expect disconnect after resync handshake. */
817 GOT_PING_ACK, /* set when we receive a ping_ack packet, misc wait gets woken */
820 struct drbd_bitmap; /* opaque for drbd_conf */
822 /* TODO sort members for performance
823 * MAYBE group them further */
825 /* THINK maybe we actually want to use the default "event/%s" worker threads
826 * or similar in linux 2.6, which uses per cpu data and threads.
828 * To be general, this might need a spin_lock member.
829 * For now, please use the mdev->req_lock to protect list_head,
830 * see drbd_queue_work below.
832 struct drbd_work_queue {
834 struct semaphore s; /* producers up it, worker down()s it */
835 spinlock_t q_lock; /* to protect the list. */
839 struct drbd_work_queue work;
841 struct socket *socket;
842 /* this way we get our
843 * send/receive buffers off the stack */
844 union p_polymorph sbuf;
845 union p_polymorph rbuf;
849 u64 md_offset; /* sector offset to 'super' block */
851 u64 la_size_sect; /* last agreed size, unit sectors */
857 s32 al_offset; /* signed relative sector offset to al area */
858 s32 bm_offset; /* signed relative sector offset to bitmap */
860 /* u32 al_nr_extents; important for restoring the AL
861 * is stored into sync_conf.al_extents, which in turn
862 * gets applied to act_log->nr_elements
866 /* for sync_conf and other types... */
867 #define NL_PACKET(name, number, fields) struct name { fields };
868 #define NL_INTEGER(pn,pr,member) int member;
869 #define NL_INT64(pn,pr,member) __u64 member;
870 #define NL_BIT(pn,pr,member) unsigned member:1;
871 #define NL_STRING(pn,pr,member,len) unsigned char member[len]; int member ## _len;
872 #include "linux/drbd_nl.h"
874 struct drbd_backing_dev {
875 struct block_device *backing_bdev;
876 struct block_device *md_bdev;
877 struct file *lo_file;
878 struct file *md_file;
880 struct disk_conf dc; /* The user provided config... */
881 sector_t known_size; /* last known size of that backing device */
885 struct drbd_conf *mdev;
886 struct completion event;
893 int (*io_fn)(struct drbd_conf *mdev);
894 void (*done)(struct drbd_conf *mdev, int rv);
897 enum write_ordering_e {
905 /* things that are stored as / read from meta data on disk */
908 /* configured by drbdsetup */
909 struct net_conf *net_conf; /* protected by get_net_conf() and put_net_conf() */
910 struct syncer_conf sync_conf;
911 struct drbd_backing_dev *ldev __protected_by(local);
913 sector_t p_size; /* partner's disk size */
914 struct request_queue *rq_queue;
915 struct block_device *this_bdev;
916 struct gendisk *vdisk;
918 struct drbd_socket data; /* data/barrier/cstate/parameter packets */
919 struct drbd_socket meta; /* ping/ack (metadata) packets */
920 int agreed_pro_version; /* actually used protocol version */
921 unsigned long last_received; /* in jiffies, either socket */
922 unsigned int ko_count;
923 struct drbd_work resync_work,
927 struct timer_list resync_timer;
928 struct timer_list md_sync_timer;
929 struct timer_list delay_probe_timer;
931 /* Used after attach while negotiating new disk state. */
932 union drbd_state new_state_tmp;
934 union drbd_state state;
935 wait_queue_head_t misc_wait;
936 wait_queue_head_t state_wait; /* upon each state change. */
937 unsigned int send_cnt;
938 unsigned int recv_cnt;
939 unsigned int read_cnt;
940 unsigned int writ_cnt;
941 unsigned int al_writ_cnt;
942 unsigned int bm_writ_cnt;
943 atomic_t ap_bio_cnt; /* Requests we need to complete */
944 atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */
945 atomic_t rs_pending_cnt; /* RS request/data packets on the wire */
946 atomic_t unacked_cnt; /* Need to send replys for */
947 atomic_t local_cnt; /* Waiting for local completion */
948 atomic_t net_cnt; /* Users of net_conf */
950 struct drbd_tl_epoch *unused_spare_tle; /* for pre-allocation */
951 struct drbd_tl_epoch *newest_tle;
952 struct drbd_tl_epoch *oldest_tle;
953 struct list_head out_of_sequence_requests;
954 struct hlist_head *tl_hash;
955 unsigned int tl_hash_s;
957 /* blocks to sync in this run [unit BM_BLOCK_SIZE] */
958 unsigned long rs_total;
959 /* number of sync IOs that failed in this run */
960 unsigned long rs_failed;
961 /* Syncer's start time [unit jiffies] */
962 unsigned long rs_start;
963 /* cumulated time in PausedSyncX state [unit jiffies] */
964 unsigned long rs_paused;
965 /* block not up-to-date at mark [unit BM_BLOCK_SIZE] */
966 unsigned long rs_mark_left;
967 /* marks's time [unit jiffies] */
968 unsigned long rs_mark_time;
969 /* skipped because csum was equeal [unit BM_BLOCK_SIZE] */
970 unsigned long rs_same_csum;
972 /* where does the admin want us to start? (sector) */
973 sector_t ov_start_sector;
974 /* where are we now? (sector) */
975 sector_t ov_position;
976 /* Start sector of out of sync range (to merge printk reporting). */
977 sector_t ov_last_oos_start;
978 /* size of out-of-sync range in sectors. */
979 sector_t ov_last_oos_size;
980 unsigned long ov_left; /* in bits */
981 struct crypto_hash *csums_tfm;
982 struct crypto_hash *verify_tfm;
984 struct drbd_thread receiver;
985 struct drbd_thread worker;
986 struct drbd_thread asender;
987 struct drbd_bitmap *bitmap;
988 unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */
990 /* Used to track operations of resync... */
991 struct lru_cache *resync;
992 /* Number of locked elements in resync LRU */
993 unsigned int resync_locked;
994 /* resync extent number waiting for application requests */
995 unsigned int resync_wenr;
999 struct drbd_epoch *current_epoch;
1000 spinlock_t epoch_lock;
1001 unsigned int epochs;
1002 enum write_ordering_e write_ordering;
1003 struct list_head active_ee; /* IO in progress */
1004 struct list_head sync_ee; /* IO in progress */
1005 struct list_head done_ee; /* send ack */
1006 struct list_head read_ee; /* IO in progress */
1007 struct list_head net_ee; /* zero-copy network send in progress */
1008 struct hlist_head *ee_hash; /* is proteced by req_lock! */
1009 unsigned int ee_hash_s;
1011 /* this one is protected by ee_lock, single thread */
1012 struct drbd_epoch_entry *last_write_w_barrier;
1014 int next_barrier_nr;
1015 struct hlist_head *app_reads_hash; /* is proteced by req_lock */
1016 struct list_head resync_reads;
1018 wait_queue_head_t ee_wait;
1019 struct page *md_io_page; /* one page buffer for md_io */
1020 struct page *md_io_tmpp; /* for logical_block_size != 512 */
1021 struct mutex md_io_mutex; /* protects the md_io_buffer */
1023 wait_queue_head_t al_wait;
1024 struct lru_cache *act_log; /* activity log */
1025 unsigned int al_tr_number;
1027 int al_tr_pos; /* position of the next transaction in the journal */
1028 struct crypto_hash *cram_hmac_tfm;
1029 struct crypto_hash *integrity_w_tfm; /* to be used by the worker thread */
1030 struct crypto_hash *integrity_r_tfm; /* to be used by the receiver thread */
1034 wait_queue_head_t seq_wait;
1035 atomic_t packet_seq;
1036 unsigned int peer_seq;
1037 spinlock_t peer_seq_lock;
1039 unsigned long comm_bm_set; /* communicated number of set bits. */
1040 cpumask_var_t cpu_mask;
1041 struct bm_io_work bm_io_work;
1042 u64 ed_uuid; /* UUID of the exposed data */
1043 struct mutex state_mutex;
1044 char congestion_reason; /* Why we where congested... */
1045 struct list_head delay_probes; /* protected by peer_seq_lock */
1046 int data_delay; /* Delay of packets on the data-sock behind meta-sock */
1047 unsigned int delay_seq; /* To generate sequence numbers of delay probes */
1048 struct timeval dps_time; /* delay-probes-start-time */
1049 unsigned int dp_volume_last; /* send_cnt of last delay probe */
1050 int c_sync_rate; /* current resync rate after delay_probe magic */
1053 static inline struct drbd_conf *minor_to_mdev(unsigned int minor)
1055 struct drbd_conf *mdev;
1057 mdev = minor < minor_count ? minor_table[minor] : NULL;
1062 static inline unsigned int mdev_to_minor(struct drbd_conf *mdev)
1067 /* returns 1 if it was successfull,
1068 * returns 0 if there was no data socket.
1069 * so wherever you are going to use the data.socket, e.g. do
1070 * if (!drbd_get_data_sock(mdev))
1073 * drbd_put_data_sock(mdev);
1075 static inline int drbd_get_data_sock(struct drbd_conf *mdev)
1077 mutex_lock(&mdev->data.mutex);
1078 /* drbd_disconnect() could have called drbd_free_sock()
1079 * while we were waiting in down()... */
1080 if (unlikely(mdev->data.socket == NULL)) {
1081 mutex_unlock(&mdev->data.mutex);
1087 static inline void drbd_put_data_sock(struct drbd_conf *mdev)
1089 mutex_unlock(&mdev->data.mutex);
1093 * function declarations
1094 *************************/
1098 enum chg_state_flags {
1101 CS_WAIT_COMPLETE = 4,
1103 CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE,
1108 DDSF_NO_RESYNC = 2, /* Do not run a resync for the new space */
1111 extern void drbd_init_set_defaults(struct drbd_conf *mdev);
1112 extern int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
1113 union drbd_state mask, union drbd_state val);
1114 extern void drbd_force_state(struct drbd_conf *, union drbd_state,
1116 extern int _drbd_request_state(struct drbd_conf *, union drbd_state,
1117 union drbd_state, enum chg_state_flags);
1118 extern int __drbd_set_state(struct drbd_conf *, union drbd_state,
1119 enum chg_state_flags, struct completion *done);
1120 extern void print_st_err(struct drbd_conf *, union drbd_state,
1121 union drbd_state, int);
1122 extern int drbd_thread_start(struct drbd_thread *thi);
1123 extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait);
1125 extern void drbd_thread_current_set_cpu(struct drbd_conf *mdev);
1126 extern void drbd_calc_cpu_mask(struct drbd_conf *mdev);
1128 #define drbd_thread_current_set_cpu(A) ({})
1129 #define drbd_calc_cpu_mask(A) ({})
1131 extern void drbd_free_resources(struct drbd_conf *mdev);
1132 extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
1133 unsigned int set_size);
1134 extern void tl_clear(struct drbd_conf *mdev);
1135 extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *);
1136 extern void drbd_free_sock(struct drbd_conf *mdev);
1137 extern int drbd_send(struct drbd_conf *mdev, struct socket *sock,
1138 void *buf, size_t size, unsigned msg_flags);
1139 extern int drbd_send_protocol(struct drbd_conf *mdev);
1140 extern int drbd_send_uuids(struct drbd_conf *mdev);
1141 extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev);
1142 extern int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val);
1143 extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags);
1144 extern int _drbd_send_state(struct drbd_conf *mdev);
1145 extern int drbd_send_state(struct drbd_conf *mdev);
1146 extern int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
1147 enum drbd_packets cmd, struct p_header *h,
1148 size_t size, unsigned msg_flags);
1149 #define USE_DATA_SOCKET 1
1150 #define USE_META_SOCKET 0
1151 extern int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
1152 enum drbd_packets cmd, struct p_header *h,
1154 extern int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd,
1155 char *data, size_t size);
1156 extern int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc);
1157 extern int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr,
1159 extern int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
1160 struct drbd_epoch_entry *e);
1161 extern int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
1162 struct p_block_req *rp);
1163 extern int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
1165 extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
1166 sector_t sector, int blksize, u64 block_id);
1167 extern int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
1168 struct drbd_epoch_entry *e);
1169 extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req);
1170 extern int _drbd_send_barrier(struct drbd_conf *mdev,
1171 struct drbd_tl_epoch *barrier);
1172 extern int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
1173 sector_t sector, int size, u64 block_id);
1174 extern int drbd_send_drequest_csum(struct drbd_conf *mdev,
1175 sector_t sector,int size,
1176 void *digest, int digest_size,
1177 enum drbd_packets cmd);
1178 extern int drbd_send_ov_request(struct drbd_conf *mdev,sector_t sector,int size);
1180 extern int drbd_send_bitmap(struct drbd_conf *mdev);
1181 extern int _drbd_send_bitmap(struct drbd_conf *mdev);
1182 extern int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode);
1183 extern void drbd_free_bc(struct drbd_backing_dev *ldev);
1184 extern void drbd_mdev_cleanup(struct drbd_conf *mdev);
1186 /* drbd_meta-data.c (still in drbd_main.c) */
1187 extern void drbd_md_sync(struct drbd_conf *mdev);
1188 extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev);
1189 /* maybe define them below as inline? */
1190 extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local);
1191 extern void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local);
1192 extern void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local);
1193 extern void _drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local);
1194 extern void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local);
1195 extern void drbd_md_set_flag(struct drbd_conf *mdev, int flags) __must_hold(local);
1196 extern void drbd_md_clear_flag(struct drbd_conf *mdev, int flags)__must_hold(local);
1197 extern int drbd_md_test_flag(struct drbd_backing_dev *, int);
1198 extern void drbd_md_mark_dirty(struct drbd_conf *mdev);
1199 extern void drbd_queue_bitmap_io(struct drbd_conf *mdev,
1200 int (*io_fn)(struct drbd_conf *),
1201 void (*done)(struct drbd_conf *, int),
1203 extern int drbd_bmio_set_n_write(struct drbd_conf *mdev);
1204 extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev);
1205 extern int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why);
1209 We reserve a 128MB Block (4k aligned)
1210 * either at the end of the backing device
1211 * or on a separate meta data device. */
1213 #define MD_RESERVED_SECT (128LU << 11) /* 128 MB, unit sectors */
1214 /* The following numbers are sectors */
1215 #define MD_AL_OFFSET 8 /* 8 Sectors after start of meta area */
1216 #define MD_AL_MAX_SIZE 64 /* = 32 kb LOG ~ 3776 extents ~ 14 GB Storage */
1217 /* Allows up to about 3.8TB */
1218 #define MD_BM_OFFSET (MD_AL_OFFSET + MD_AL_MAX_SIZE)
1220 /* Since the smalles IO unit is usually 512 byte */
1221 #define MD_SECTOR_SHIFT 9
1222 #define MD_SECTOR_SIZE (1<<MD_SECTOR_SHIFT)
1225 #define AL_EXTENTS_PT ((MD_SECTOR_SIZE-12)/8-1) /* 61 ; Extents per 512B sector */
1226 #define AL_EXTENT_SHIFT 22 /* One extent represents 4M Storage */
1227 #define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT)
1229 #if BITS_PER_LONG == 32
1231 #define cpu_to_lel(A) cpu_to_le32(A)
1232 #define lel_to_cpu(A) le32_to_cpu(A)
1233 #elif BITS_PER_LONG == 64
1235 #define cpu_to_lel(A) cpu_to_le64(A)
1236 #define lel_to_cpu(A) le64_to_cpu(A)
1238 #error "LN2 of BITS_PER_LONG unknown!"
1242 /* 16MB sized 'bitmap extent' to track syncer usage */
1244 int rs_left; /* number of bits set (out of sync) in this extent. */
1245 int rs_failed; /* number of failed resync requests in this extent. */
1246 unsigned long flags;
1247 struct lc_element lce;
1250 #define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */
1251 #define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */
1255 * We need to store one bit for a block.
1256 * Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap.
1257 * Bit 0 ==> local node thinks this block is binary identical on both nodes
1258 * Bit 1 ==> local node thinks this block needs to be synced.
1261 #define BM_BLOCK_SHIFT 12 /* 4k per bit */
1262 #define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT)
1263 /* (9+3) : 512 bytes @ 8 bits; representing 16M storage
1264 * per sector of on disk bitmap */
1265 #define BM_EXT_SHIFT (BM_BLOCK_SHIFT + MD_SECTOR_SHIFT + 3) /* = 24 */
1266 #define BM_EXT_SIZE (1<<BM_EXT_SHIFT)
1268 #if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12)
1269 #error "HAVE YOU FIXED drbdmeta AS WELL??"
1272 /* thus many _storage_ sectors are described by one bit */
1273 #define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9))
1274 #define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9))
1275 #define BM_SECT_PER_BIT BM_BIT_TO_SECT(1)
1277 /* bit to represented kilo byte conversion */
1278 #define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10))
1280 /* in which _bitmap_ extent (resp. sector) the bit for a certain
1281 * _storage_ sector is located in */
1282 #define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9))
1284 /* how much _storage_ sectors we have per bitmap sector */
1285 #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9))
1286 #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1)
1288 /* in one sector of the bitmap, we have this many activity_log extents. */
1289 #define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT))
1290 #define BM_WORDS_PER_AL_EXT (1 << (AL_EXTENT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL))
1292 #define BM_BLOCKS_PER_BM_EXT_B (BM_EXT_SHIFT - BM_BLOCK_SHIFT)
1293 #define BM_BLOCKS_PER_BM_EXT_MASK ((1<<BM_BLOCKS_PER_BM_EXT_B) - 1)
1295 /* the extent in "PER_EXTENT" below is an activity log extent
1296 * we need that many (long words/bytes) to store the bitmap
1297 * of one AL_EXTENT_SIZE chunk of storage.
1298 * we can store the bitmap for that many AL_EXTENTS within
1299 * one sector of the _on_disk_ bitmap:
1300 * bit 0 bit 37 bit 38 bit (512*8)-1
1301 * ...|........|........|.. // ..|........|
1302 * sect. 0 `296 `304 ^(512*8*8)-1
1304 #define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG )
1305 #define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128
1306 #define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4
1309 #define DRBD_MAX_SECTORS_32 (0xffffffffLU)
1310 #define DRBD_MAX_SECTORS_BM \
1311 ((MD_RESERVED_SECT - MD_BM_OFFSET) * (1LL<<(BM_EXT_SHIFT-9)))
1312 #if DRBD_MAX_SECTORS_BM < DRBD_MAX_SECTORS_32
1313 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM
1314 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_BM
1315 #elif !defined(CONFIG_LBDAF) && BITS_PER_LONG == 32
1316 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_32
1317 #define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_32
1319 #define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM
1320 /* 16 TB in units of sectors */
1321 #if BITS_PER_LONG == 32
1322 /* adjust by one page worth of bitmap,
1323 * so we won't wrap around in drbd_bm_find_next_bit.
1324 * you should use 64bit OS for that much storage, anyways. */
1325 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff)
1327 #define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0x1LU << 32)
1331 /* Sector shift value for the "hash" functions of tl_hash and ee_hash tables.
1332 * With a value of 6 all IO in one 32K block make it to the same slot of the
1335 #define DRBD_MAX_SEGMENT_SIZE (1U<<(9+HT_SHIFT))
1337 /* Number of elements in the app_reads_hash */
1338 #define APP_R_HSIZE 15
1340 extern int drbd_bm_init(struct drbd_conf *mdev);
1341 extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors, int set_new_bits);
1342 extern void drbd_bm_cleanup(struct drbd_conf *mdev);
1343 extern void drbd_bm_set_all(struct drbd_conf *mdev);
1344 extern void drbd_bm_clear_all(struct drbd_conf *mdev);
1345 extern int drbd_bm_set_bits(
1346 struct drbd_conf *mdev, unsigned long s, unsigned long e);
1347 extern int drbd_bm_clear_bits(
1348 struct drbd_conf *mdev, unsigned long s, unsigned long e);
1349 /* bm_set_bits variant for use while holding drbd_bm_lock */
1350 extern void _drbd_bm_set_bits(struct drbd_conf *mdev,
1351 const unsigned long s, const unsigned long e);
1352 extern int drbd_bm_test_bit(struct drbd_conf *mdev, unsigned long bitnr);
1353 extern int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr);
1354 extern int drbd_bm_write_sect(struct drbd_conf *mdev, unsigned long enr) __must_hold(local);
1355 extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local);
1356 extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local);
1357 extern unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev,
1358 unsigned long al_enr);
1359 extern size_t drbd_bm_words(struct drbd_conf *mdev);
1360 extern unsigned long drbd_bm_bits(struct drbd_conf *mdev);
1361 extern sector_t drbd_bm_capacity(struct drbd_conf *mdev);
1362 extern unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo);
1363 /* bm_find_next variants for use while you hold drbd_bm_lock() */
1364 extern unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo);
1365 extern unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo);
1366 extern unsigned long drbd_bm_total_weight(struct drbd_conf *mdev);
1367 extern int drbd_bm_rs_done(struct drbd_conf *mdev);
1368 /* for receive_bitmap */
1369 extern void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset,
1370 size_t number, unsigned long *buffer);
1371 /* for _drbd_send_bitmap and drbd_bm_write_sect */
1372 extern void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset,
1373 size_t number, unsigned long *buffer);
1375 extern void drbd_bm_lock(struct drbd_conf *mdev, char *why);
1376 extern void drbd_bm_unlock(struct drbd_conf *mdev);
1378 extern int drbd_bm_count_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e);
1381 extern struct kmem_cache *drbd_request_cache;
1382 extern struct kmem_cache *drbd_ee_cache; /* epoch entries */
1383 extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
1384 extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
1385 extern mempool_t *drbd_request_mempool;
1386 extern mempool_t *drbd_ee_mempool;
1388 extern struct page *drbd_pp_pool; /* drbd's page pool */
1389 extern spinlock_t drbd_pp_lock;
1390 extern int drbd_pp_vacant;
1391 extern wait_queue_head_t drbd_pp_wait;
1393 extern rwlock_t global_state_lock;
1395 extern struct drbd_conf *drbd_new_device(unsigned int minor);
1396 extern void drbd_free_mdev(struct drbd_conf *mdev);
1398 extern int proc_details;
1401 extern int drbd_make_request_26(struct request_queue *q, struct bio *bio);
1402 extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req);
1403 extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec);
1404 extern int is_valid_ar_handle(struct drbd_request *, sector_t);
1408 extern void drbd_suspend_io(struct drbd_conf *mdev);
1409 extern void drbd_resume_io(struct drbd_conf *mdev);
1410 extern char *ppsize(char *buf, unsigned long long size);
1411 extern sector_t drbd_new_dev_size(struct drbd_conf *, struct drbd_backing_dev *, int);
1412 enum determine_dev_size { dev_size_error = -1, unchanged = 0, shrunk = 1, grew = 2 };
1413 extern enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *, enum dds_flags) __must_hold(local);
1414 extern void resync_after_online_grow(struct drbd_conf *);
1415 extern void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int) __must_hold(local);
1416 extern int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role,
1418 enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev);
1419 extern int drbd_khelper(struct drbd_conf *mdev, char *cmd);
1422 extern int drbd_worker(struct drbd_thread *thi);
1423 extern int drbd_alter_sa(struct drbd_conf *mdev, int na);
1424 extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side);
1425 extern void resume_next_sg(struct drbd_conf *mdev);
1426 extern void suspend_other_sg(struct drbd_conf *mdev);
1427 extern int drbd_resync_finished(struct drbd_conf *mdev);
1428 /* maybe rather drbd_main.c ? */
1429 extern int drbd_md_sync_page_io(struct drbd_conf *mdev,
1430 struct drbd_backing_dev *bdev, sector_t sector, int rw);
1431 extern void drbd_ov_oos_found(struct drbd_conf*, sector_t, int);
1433 static inline void ov_oos_print(struct drbd_conf *mdev)
1435 if (mdev->ov_last_oos_size) {
1436 dev_err(DEV, "Out of sync: start=%llu, size=%lu (sectors)\n",
1437 (unsigned long long)mdev->ov_last_oos_start,
1438 (unsigned long)mdev->ov_last_oos_size);
1440 mdev->ov_last_oos_size=0;
1444 extern void drbd_csum(struct drbd_conf *, struct crypto_hash *, struct bio *, void *);
1445 /* worker callbacks */
1446 extern int w_req_cancel_conflict(struct drbd_conf *, struct drbd_work *, int);
1447 extern int w_read_retry_remote(struct drbd_conf *, struct drbd_work *, int);
1448 extern int w_e_end_data_req(struct drbd_conf *, struct drbd_work *, int);
1449 extern int w_e_end_rsdata_req(struct drbd_conf *, struct drbd_work *, int);
1450 extern int w_e_end_csum_rs_req(struct drbd_conf *, struct drbd_work *, int);
1451 extern int w_e_end_ov_reply(struct drbd_conf *, struct drbd_work *, int);
1452 extern int w_e_end_ov_req(struct drbd_conf *, struct drbd_work *, int);
1453 extern int w_ov_finished(struct drbd_conf *, struct drbd_work *, int);
1454 extern int w_resync_inactive(struct drbd_conf *, struct drbd_work *, int);
1455 extern int w_resume_next_sg(struct drbd_conf *, struct drbd_work *, int);
1456 extern int w_io_error(struct drbd_conf *, struct drbd_work *, int);
1457 extern int w_send_write_hint(struct drbd_conf *, struct drbd_work *, int);
1458 extern int w_make_resync_request(struct drbd_conf *, struct drbd_work *, int);
1459 extern int w_send_dblock(struct drbd_conf *, struct drbd_work *, int);
1460 extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int);
1461 extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int);
1462 extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int);
1463 extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int);
1465 extern void resync_timer_fn(unsigned long data);
1467 /* drbd_receiver.c */
1468 extern int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list);
1469 extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev,
1472 unsigned int data_size,
1473 gfp_t gfp_mask) __must_hold(local);
1474 extern void drbd_free_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e);
1475 extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev,
1476 struct list_head *head);
1477 extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev,
1478 struct list_head *head);
1479 extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled);
1480 extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed);
1481 extern void drbd_flush_workqueue(struct drbd_conf *mdev);
1483 /* yes, there is kernel_setsockopt, but only since 2.6.18. we don't need to
1484 * mess with get_fs/set_fs, we know we are KERNEL_DS always. */
1485 static inline int drbd_setsockopt(struct socket *sock, int level, int optname,
1486 char __user *optval, int optlen)
1489 if (level == SOL_SOCKET)
1490 err = sock_setsockopt(sock, level, optname, optval, optlen);
1492 err = sock->ops->setsockopt(sock, level, optname, optval,
1497 static inline void drbd_tcp_cork(struct socket *sock)
1500 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
1501 (char __user *)&val, sizeof(val));
1504 static inline void drbd_tcp_uncork(struct socket *sock)
1507 (void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
1508 (char __user *)&val, sizeof(val));
1511 static inline void drbd_tcp_nodelay(struct socket *sock)
1514 (void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY,
1515 (char __user *)&val, sizeof(val));
1518 static inline void drbd_tcp_quickack(struct socket *sock)
1521 (void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK,
1522 (char __user *)&val, sizeof(val));
1525 void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo);
1528 extern struct proc_dir_entry *drbd_proc;
1529 extern const struct file_operations drbd_proc_fops;
1530 extern const char *drbd_conn_str(enum drbd_conns s);
1531 extern const char *drbd_role_str(enum drbd_role s);
1534 extern void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector);
1535 extern void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector);
1536 extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector);
1537 extern int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector);
1538 extern int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector);
1539 extern void drbd_rs_cancel_all(struct drbd_conf *mdev);
1540 extern int drbd_rs_del_all(struct drbd_conf *mdev);
1541 extern void drbd_rs_failed_io(struct drbd_conf *mdev,
1542 sector_t sector, int size);
1543 extern int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *);
1544 extern void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector,
1545 int size, const char *file, const unsigned int line);
1546 #define drbd_set_in_sync(mdev, sector, size) \
1547 __drbd_set_in_sync(mdev, sector, size, __FILE__, __LINE__)
1548 extern void __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector,
1549 int size, const char *file, const unsigned int line);
1550 #define drbd_set_out_of_sync(mdev, sector, size) \
1551 __drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__)
1552 extern void drbd_al_apply_to_bm(struct drbd_conf *mdev);
1553 extern void drbd_al_to_on_disk_bm(struct drbd_conf *mdev);
1554 extern void drbd_al_shrink(struct drbd_conf *mdev);
1559 void drbd_nl_cleanup(void);
1560 int __init drbd_nl_init(void);
1561 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state);
1562 void drbd_bcast_sync_progress(struct drbd_conf *mdev);
1563 void drbd_bcast_ee(struct drbd_conf *mdev,
1564 const char *reason, const int dgs,
1565 const char* seen_hash, const char* calc_hash,
1566 const struct drbd_epoch_entry* e);
1570 * DOC: DRBD State macros
1572 * These macros are used to express state changes in easily readable form.
1574 * The NS macros expand to a mask and a value, that can be bit ored onto the
1575 * current state as soon as the spinlock (req_lock) was taken.
1577 * The _NS macros are used for state functions that get called with the
1578 * spinlock. These macros expand directly to the new state value.
1580 * Besides the basic forms NS() and _NS() additional _?NS[23] are defined
1581 * to express state changes that affect more than one aspect of the state.
1583 * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY)
1584 * Means that the network connection was established and that the peer
1585 * is in secondary role.
1587 #define role_MASK R_MASK
1588 #define peer_MASK R_MASK
1589 #define disk_MASK D_MASK
1590 #define pdsk_MASK D_MASK
1591 #define conn_MASK C_MASK
1593 #define user_isp_MASK 1
1594 #define aftr_isp_MASK 1
1597 ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \
1598 ({ union drbd_state val; val.i = 0; val.T = (S); val; })
1599 #define NS2(T1, S1, T2, S2) \
1600 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
1601 mask.T2 = T2##_MASK; mask; }), \
1602 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \
1603 val.T2 = (S2); val; })
1604 #define NS3(T1, S1, T2, S2, T3, S3) \
1605 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
1606 mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \
1607 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \
1608 val.T2 = (S2); val.T3 = (S3); val; })
1610 #define _NS(D, T, S) \
1611 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; })
1612 #define _NS2(D, T1, S1, T2, S2) \
1613 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
1614 __ns.T2 = (S2); __ns; })
1615 #define _NS3(D, T1, S1, T2, S2, T3, S3) \
1616 D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
1617 __ns.T2 = (S2); __ns.T3 = (S3); __ns; })
1620 * inline helper functions
1621 *************************/
1623 static inline void drbd_state_lock(struct drbd_conf *mdev)
1625 wait_event(mdev->misc_wait,
1626 !test_and_set_bit(CLUSTER_ST_CHANGE, &mdev->flags));
1629 static inline void drbd_state_unlock(struct drbd_conf *mdev)
1631 clear_bit(CLUSTER_ST_CHANGE, &mdev->flags);
1632 wake_up(&mdev->misc_wait);
1635 static inline int _drbd_set_state(struct drbd_conf *mdev,
1636 union drbd_state ns, enum chg_state_flags flags,
1637 struct completion *done)
1641 read_lock(&global_state_lock);
1642 rv = __drbd_set_state(mdev, ns, flags, done);
1643 read_unlock(&global_state_lock);
1649 * drbd_request_state() - Reqest a state change
1650 * @mdev: DRBD device.
1651 * @mask: mask of state bits to change.
1652 * @val: value of new state bits.
1654 * This is the most graceful way of requesting a state change. It is verbose
1655 * quite verbose in case the state change is not possible, and all those
1656 * state changes are globally serialized.
1658 static inline int drbd_request_state(struct drbd_conf *mdev,
1659 union drbd_state mask,
1660 union drbd_state val)
1662 return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED);
1665 #define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__)
1666 static inline void __drbd_chk_io_error_(struct drbd_conf *mdev, int forcedetach, const char *where)
1668 switch (mdev->ldev->dc.on_io_error) {
1671 if (printk_ratelimit())
1672 dev_err(DEV, "Local IO failed in %s."
1673 "Passing error on...\n", where);
1676 /* NOTE fall through to detach case if forcedetach set */
1678 case EP_CALL_HELPER:
1679 if (mdev->state.disk > D_FAILED) {
1680 _drbd_set_state(_NS(mdev, disk, D_FAILED), CS_HARD, NULL);
1681 dev_err(DEV, "Local IO failed in %s."
1682 "Detaching...\n", where);
1689 * drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers
1690 * @mdev: DRBD device.
1691 * @error: Error code passed to the IO completion callback
1692 * @forcedetach: Force detach. I.e. the error happened while accessing the meta data
1694 * See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED)
1696 #define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__)
1697 static inline void drbd_chk_io_error_(struct drbd_conf *mdev,
1698 int error, int forcedetach, const char *where)
1701 unsigned long flags;
1702 spin_lock_irqsave(&mdev->req_lock, flags);
1703 __drbd_chk_io_error_(mdev, forcedetach, where);
1704 spin_unlock_irqrestore(&mdev->req_lock, flags);
1710 * drbd_md_first_sector() - Returns the first sector number of the meta data area
1711 * @bdev: Meta data block device.
1713 * BTW, for internal meta data, this happens to be the maximum capacity
1714 * we could agree upon with our peer node.
1716 static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev)
1718 switch (bdev->dc.meta_dev_idx) {
1719 case DRBD_MD_INDEX_INTERNAL:
1720 case DRBD_MD_INDEX_FLEX_INT:
1721 return bdev->md.md_offset + bdev->md.bm_offset;
1722 case DRBD_MD_INDEX_FLEX_EXT:
1724 return bdev->md.md_offset;
1729 * drbd_md_last_sector() - Return the last sector number of the meta data area
1730 * @bdev: Meta data block device.
1732 static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev)
1734 switch (bdev->dc.meta_dev_idx) {
1735 case DRBD_MD_INDEX_INTERNAL:
1736 case DRBD_MD_INDEX_FLEX_INT:
1737 return bdev->md.md_offset + MD_AL_OFFSET - 1;
1738 case DRBD_MD_INDEX_FLEX_EXT:
1740 return bdev->md.md_offset + bdev->md.md_size_sect;
1744 /* Returns the number of 512 byte sectors of the device */
1745 static inline sector_t drbd_get_capacity(struct block_device *bdev)
1747 /* return bdev ? get_capacity(bdev->bd_disk) : 0; */
1748 return bdev ? bdev->bd_inode->i_size >> 9 : 0;
1752 * drbd_get_max_capacity() - Returns the capacity we announce to out peer
1753 * @bdev: Meta data block device.
1755 * returns the capacity we announce to out peer. we clip ourselves at the
1756 * various MAX_SECTORS, because if we don't, current implementation will
1757 * oops sooner or later
1759 static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev)
1762 switch (bdev->dc.meta_dev_idx) {
1763 case DRBD_MD_INDEX_INTERNAL:
1764 case DRBD_MD_INDEX_FLEX_INT:
1765 s = drbd_get_capacity(bdev->backing_bdev)
1766 ? min_t(sector_t, DRBD_MAX_SECTORS_FLEX,
1767 drbd_md_first_sector(bdev))
1770 case DRBD_MD_INDEX_FLEX_EXT:
1771 s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX,
1772 drbd_get_capacity(bdev->backing_bdev));
1773 /* clip at maximum size the meta device can support */
1774 s = min_t(sector_t, s,
1775 BM_EXT_TO_SECT(bdev->md.md_size_sect
1776 - bdev->md.bm_offset));
1779 s = min_t(sector_t, DRBD_MAX_SECTORS,
1780 drbd_get_capacity(bdev->backing_bdev));
1786 * drbd_md_ss__() - Return the sector number of our meta data super block
1787 * @mdev: DRBD device.
1788 * @bdev: Meta data block device.
1790 static inline sector_t drbd_md_ss__(struct drbd_conf *mdev,
1791 struct drbd_backing_dev *bdev)
1793 switch (bdev->dc.meta_dev_idx) {
1794 default: /* external, some index */
1795 return MD_RESERVED_SECT * bdev->dc.meta_dev_idx;
1796 case DRBD_MD_INDEX_INTERNAL:
1797 /* with drbd08, internal meta data is always "flexible" */
1798 case DRBD_MD_INDEX_FLEX_INT:
1799 /* sizeof(struct md_on_disk_07) == 4k
1800 * position: last 4k aligned block of 4k size */
1801 if (!bdev->backing_bdev) {
1802 if (__ratelimit(&drbd_ratelimit_state)) {
1803 dev_err(DEV, "bdev->backing_bdev==NULL\n");
1808 return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL)
1810 case DRBD_MD_INDEX_FLEX_EXT:
1816 _drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w)
1818 list_add_tail(&w->list, &q->q);
1823 drbd_queue_work_front(struct drbd_work_queue *q, struct drbd_work *w)
1825 unsigned long flags;
1826 spin_lock_irqsave(&q->q_lock, flags);
1827 list_add(&w->list, &q->q);
1828 up(&q->s); /* within the spinlock,
1829 see comment near end of drbd_worker() */
1830 spin_unlock_irqrestore(&q->q_lock, flags);
1834 drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w)
1836 unsigned long flags;
1837 spin_lock_irqsave(&q->q_lock, flags);
1838 list_add_tail(&w->list, &q->q);
1839 up(&q->s); /* within the spinlock,
1840 see comment near end of drbd_worker() */
1841 spin_unlock_irqrestore(&q->q_lock, flags);
1844 static inline void wake_asender(struct drbd_conf *mdev)
1846 if (test_bit(SIGNAL_ASENDER, &mdev->flags))
1847 force_sig(DRBD_SIG, mdev->asender.task);
1850 static inline void request_ping(struct drbd_conf *mdev)
1852 set_bit(SEND_PING, &mdev->flags);
1856 static inline int drbd_send_short_cmd(struct drbd_conf *mdev,
1857 enum drbd_packets cmd)
1860 return drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, &h, sizeof(h));
1863 static inline int drbd_send_ping(struct drbd_conf *mdev)
1866 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING, &h, sizeof(h));
1869 static inline int drbd_send_ping_ack(struct drbd_conf *mdev)
1872 return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING_ACK, &h, sizeof(h));
1875 static inline void drbd_thread_stop(struct drbd_thread *thi)
1877 _drbd_thread_stop(thi, FALSE, TRUE);
1880 static inline void drbd_thread_stop_nowait(struct drbd_thread *thi)
1882 _drbd_thread_stop(thi, FALSE, FALSE);
1885 static inline void drbd_thread_restart_nowait(struct drbd_thread *thi)
1887 _drbd_thread_stop(thi, TRUE, FALSE);
1890 /* counts how many answer packets packets we expect from our peer,
1891 * for either explicit application requests,
1892 * or implicit barrier packets as necessary.
1895 * _req_mod(req, queue_for_net_write or queue_for_net_read);
1896 * it is much easier and equally valid to count what we queue for the
1897 * worker, even before it actually was queued or send.
1898 * (drbd_make_request_common; recovery path on read io-error)
1900 * got_BarrierAck (respective tl_clear, tl_clear_barrier)
1901 * _req_mod(req, data_received)
1902 * [from receive_DataReply]
1903 * _req_mod(req, write_acked_by_peer or recv_acked_by_peer or neg_acked)
1904 * [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)]
1905 * for some reason it is NOT decreased in got_NegAck,
1906 * but in the resulting cleanup code from report_params.
1907 * we should try to remember the reason for that...
1908 * _req_mod(req, send_failed or send_canceled)
1909 * _req_mod(req, connection_lost_while_pending)
1910 * [from tl_clear_barrier]
1912 static inline void inc_ap_pending(struct drbd_conf *mdev)
1914 atomic_inc(&mdev->ap_pending_cnt);
1917 #define ERR_IF_CNT_IS_NEGATIVE(which) \
1918 if (atomic_read(&mdev->which) < 0) \
1919 dev_err(DEV, "in %s:%d: " #which " = %d < 0 !\n", \
1920 __func__ , __LINE__ , \
1921 atomic_read(&mdev->which))
1923 #define dec_ap_pending(mdev) do { \
1924 typecheck(struct drbd_conf *, mdev); \
1925 if (atomic_dec_and_test(&mdev->ap_pending_cnt)) \
1926 wake_up(&mdev->misc_wait); \
1927 ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt); } while (0)
1929 /* counts how many resync-related answers we still expect from the peer
1931 * C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY)
1932 * C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK whith ID_SYNCER)
1933 * (or P_NEG_ACK with ID_SYNCER)
1935 static inline void inc_rs_pending(struct drbd_conf *mdev)
1937 atomic_inc(&mdev->rs_pending_cnt);
1940 #define dec_rs_pending(mdev) do { \
1941 typecheck(struct drbd_conf *, mdev); \
1942 atomic_dec(&mdev->rs_pending_cnt); \
1943 ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt); } while (0)
1945 /* counts how many answers we still need to send to the peer.
1947 * receive_Data unless protocol A;
1948 * we need to send a P_RECV_ACK (proto B)
1949 * or P_WRITE_ACK (proto C)
1950 * receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK
1951 * receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA
1952 * receive_Barrier_* we need to send a P_BARRIER_ACK
1954 static inline void inc_unacked(struct drbd_conf *mdev)
1956 atomic_inc(&mdev->unacked_cnt);
1959 #define dec_unacked(mdev) do { \
1960 typecheck(struct drbd_conf *, mdev); \
1961 atomic_dec(&mdev->unacked_cnt); \
1962 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0)
1964 #define sub_unacked(mdev, n) do { \
1965 typecheck(struct drbd_conf *, mdev); \
1966 atomic_sub(n, &mdev->unacked_cnt); \
1967 ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0)
1970 static inline void put_net_conf(struct drbd_conf *mdev)
1972 if (atomic_dec_and_test(&mdev->net_cnt))
1973 wake_up(&mdev->misc_wait);
1977 * get_net_conf() - Increase ref count on mdev->net_conf; Returns 0 if nothing there
1978 * @mdev: DRBD device.
1980 * You have to call put_net_conf() when finished working with mdev->net_conf.
1982 static inline int get_net_conf(struct drbd_conf *mdev)
1986 atomic_inc(&mdev->net_cnt);
1987 have_net_conf = mdev->state.conn >= C_UNCONNECTED;
1990 return have_net_conf;
1994 * get_ldev() - Increase the ref count on mdev->ldev. Returns 0 if there is no ldev
1997 * You have to call put_ldev() when finished working with mdev->ldev.
1999 #define get_ldev(M) __cond_lock(local, _get_ldev_if_state(M,D_INCONSISTENT))
2000 #define get_ldev_if_state(M,MINS) __cond_lock(local, _get_ldev_if_state(M,MINS))
2002 static inline void put_ldev(struct drbd_conf *mdev)
2005 if (atomic_dec_and_test(&mdev->local_cnt))
2006 wake_up(&mdev->misc_wait);
2007 D_ASSERT(atomic_read(&mdev->local_cnt) >= 0);
2011 static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
2015 atomic_inc(&mdev->local_cnt);
2016 io_allowed = (mdev->state.disk >= mins);
2022 extern int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins);
2025 /* you must have an "get_ldev" reference */
2026 static inline void drbd_get_syncer_progress(struct drbd_conf *mdev,
2027 unsigned long *bits_left, unsigned int *per_mil_done)
2030 * this is to break it at compile time when we change that
2031 * (we may feel 4TB maximum storage per drbd is not enough)
2033 typecheck(unsigned long, mdev->rs_total);
2035 /* note: both rs_total and rs_left are in bits, i.e. in
2036 * units of BM_BLOCK_SIZE.
2037 * for the percentage, we don't care. */
2039 *bits_left = drbd_bm_total_weight(mdev) - mdev->rs_failed;
2040 /* >> 10 to prevent overflow,
2041 * +1 to prevent division by zero */
2042 if (*bits_left > mdev->rs_total) {
2043 /* doh. maybe a logic bug somewhere.
2044 * may also be just a race condition
2045 * between this and a disconnect during sync.
2046 * for now, just prevent in-kernel buffer overflow.
2049 dev_warn(DEV, "cs:%s rs_left=%lu > rs_total=%lu (rs_failed %lu)\n",
2050 drbd_conn_str(mdev->state.conn),
2051 *bits_left, mdev->rs_total, mdev->rs_failed);
2054 /* make sure the calculation happens in long context */
2055 unsigned long tmp = 1000UL -
2056 (*bits_left >> 10)*1000UL
2057 / ((mdev->rs_total >> 10) + 1UL);
2058 *per_mil_done = tmp;
2063 /* this throttles on-the-fly application requests
2064 * according to max_buffers settings;
2065 * maybe re-implement using semaphores? */
2066 static inline int drbd_get_max_buffers(struct drbd_conf *mdev)
2068 int mxb = 1000000; /* arbitrary limit on open requests */
2069 if (get_net_conf(mdev)) {
2070 mxb = mdev->net_conf->max_buffers;
2076 static inline int drbd_state_is_stable(union drbd_state s)
2079 /* DO NOT add a default clause, we want the compiler to warn us
2080 * for any newly introduced state we may have forgotten to add here */
2082 switch ((enum drbd_conns)s.conn) {
2083 /* new io only accepted when there is no connection, ... */
2085 case C_WF_CONNECTION:
2086 /* ... or there is a well established connection. */
2092 case C_PAUSED_SYNC_S:
2093 case C_PAUSED_SYNC_T:
2094 /* maybe stable, look at the disk state */
2097 /* no new io accepted during tansitional states
2098 * like handshake or teardown */
2099 case C_DISCONNECTING:
2103 case C_NETWORK_FAILURE:
2104 case C_PROTOCOL_ERROR:
2106 case C_WF_REPORT_PARAMS:
2107 case C_STARTING_SYNC_S:
2108 case C_STARTING_SYNC_T:
2111 case C_WF_SYNC_UUID:
2117 switch ((enum drbd_disk_state)s.disk) {
2119 case D_INCONSISTENT:
2123 /* disk state is stable as well. */
2126 /* no new io accepted during tansitional states */
2139 static inline int __inc_ap_bio_cond(struct drbd_conf *mdev)
2141 int mxb = drbd_get_max_buffers(mdev);
2143 if (mdev->state.susp)
2145 if (test_bit(SUSPEND_IO, &mdev->flags))
2148 /* to avoid potential deadlock or bitmap corruption,
2149 * in various places, we only allow new application io
2150 * to start during "stable" states. */
2152 /* no new io accepted when attaching or detaching the disk */
2153 if (!drbd_state_is_stable(mdev->state))
2156 /* since some older kernels don't have atomic_add_unless,
2157 * and we are within the spinlock anyways, we have this workaround. */
2158 if (atomic_read(&mdev->ap_bio_cnt) > mxb)
2160 if (test_bit(BITMAP_IO, &mdev->flags))
2165 /* I'd like to use wait_event_lock_irq,
2166 * but I'm not sure when it got introduced,
2167 * and not sure when it has 3 or 4 arguments */
2168 static inline void inc_ap_bio(struct drbd_conf *mdev, int one_or_two)
2170 /* compare with after_state_ch,
2171 * os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S */
2175 * as long as the device is suspended
2176 * until the bitmap is no longer on the fly during connection
2177 * handshake as long as we would exeed the max_buffer limit.
2179 * to avoid races with the reconnect code,
2180 * we need to atomic_inc within the spinlock. */
2182 spin_lock_irq(&mdev->req_lock);
2183 while (!__inc_ap_bio_cond(mdev)) {
2184 prepare_to_wait(&mdev->misc_wait, &wait, TASK_UNINTERRUPTIBLE);
2185 spin_unlock_irq(&mdev->req_lock);
2187 finish_wait(&mdev->misc_wait, &wait);
2188 spin_lock_irq(&mdev->req_lock);
2190 atomic_add(one_or_two, &mdev->ap_bio_cnt);
2191 spin_unlock_irq(&mdev->req_lock);
2194 static inline void dec_ap_bio(struct drbd_conf *mdev)
2196 int mxb = drbd_get_max_buffers(mdev);
2197 int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt);
2199 D_ASSERT(ap_bio >= 0);
2200 /* this currently does wake_up for every dec_ap_bio!
2201 * maybe rather introduce some type of hysteresis?
2202 * e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */
2204 wake_up(&mdev->misc_wait);
2205 if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) {
2206 if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
2207 drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
2211 static inline void drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val)
2213 mdev->ed_uuid = val;
2216 static inline int seq_cmp(u32 a, u32 b)
2218 /* we assume wrap around at 32bit.
2219 * for wrap around at 24bit (old atomic_t),
2223 return (s32)(a) - (s32)(b);
2225 #define seq_lt(a, b) (seq_cmp((a), (b)) < 0)
2226 #define seq_gt(a, b) (seq_cmp((a), (b)) > 0)
2227 #define seq_ge(a, b) (seq_cmp((a), (b)) >= 0)
2228 #define seq_le(a, b) (seq_cmp((a), (b)) <= 0)
2229 /* CAUTION: please no side effects in arguments! */
2230 #define seq_max(a, b) ((u32)(seq_gt((a), (b)) ? (a) : (b)))
2232 static inline void update_peer_seq(struct drbd_conf *mdev, unsigned int new_seq)
2235 spin_lock(&mdev->peer_seq_lock);
2236 m = seq_max(mdev->peer_seq, new_seq);
2238 spin_unlock(&mdev->peer_seq_lock);
2240 wake_up(&mdev->seq_wait);
2243 static inline void drbd_update_congested(struct drbd_conf *mdev)
2245 struct sock *sk = mdev->data.socket->sk;
2246 if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5)
2247 set_bit(NET_CONGESTED, &mdev->flags);
2250 static inline int drbd_queue_order_type(struct drbd_conf *mdev)
2252 /* sorry, we currently have no working implementation
2253 * of distributed TCQ stuff */
2254 #ifndef QUEUE_ORDERED_NONE
2255 #define QUEUE_ORDERED_NONE 0
2257 return QUEUE_ORDERED_NONE;
2260 static inline void drbd_blk_run_queue(struct request_queue *q)
2262 if (q && q->unplug_fn)
2266 static inline void drbd_kick_lo(struct drbd_conf *mdev)
2268 if (get_ldev(mdev)) {
2269 drbd_blk_run_queue(bdev_get_queue(mdev->ldev->backing_bdev));
2274 static inline void drbd_md_flush(struct drbd_conf *mdev)
2278 if (test_bit(MD_NO_BARRIER, &mdev->flags))
2281 r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL,
2284 set_bit(MD_NO_BARRIER, &mdev->flags);
2285 dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r);