xref: /linux/drivers/block/drbd/drbd_nl.c (revision ce7240e445303de3ca66e6d08f17a2ec278a5bf6)
1 /*
2    drbd_nl.c
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 #include <linux/module.h>
27 #include <linux/drbd.h>
28 #include <linux/in.h>
29 #include <linux/fs.h>
30 #include <linux/file.h>
31 #include <linux/slab.h>
32 #include <linux/connector.h>
33 #include <linux/blkpg.h>
34 #include <linux/cpumask.h>
35 #include "drbd_int.h"
36 #include "drbd_req.h"
37 #include "drbd_wrappers.h"
38 #include <asm/unaligned.h>
39 #include <linux/drbd_tag_magic.h>
40 #include <linux/drbd_limits.h>
41 #include <linux/compiler.h>
42 #include <linux/kthread.h>
43 
44 static unsigned short *tl_add_blob(unsigned short *, enum drbd_tags, const void *, int);
45 static unsigned short *tl_add_str(unsigned short *, enum drbd_tags, const char *);
46 static unsigned short *tl_add_int(unsigned short *, enum drbd_tags, const void *);
47 
48 /* see get_sb_bdev and bd_claim */
49 static char *drbd_m_holder = "Hands off! this is DRBD's meta data device.";
50 
51 /* Generate the tag_list to struct functions */
52 #define NL_PACKET(name, number, fields) \
53 static int name ## _from_tags(struct drbd_conf *mdev, \
54 	unsigned short *tags, struct name *arg) __attribute__ ((unused)); \
55 static int name ## _from_tags(struct drbd_conf *mdev, \
56 	unsigned short *tags, struct name *arg) \
57 { \
58 	int tag; \
59 	int dlen; \
60 	\
61 	while ((tag = get_unaligned(tags++)) != TT_END) {	\
62 		dlen = get_unaligned(tags++);			\
63 		switch (tag_number(tag)) { \
64 		fields \
65 		default: \
66 			if (tag & T_MANDATORY) { \
67 				dev_err(DEV, "Unknown tag: %d\n", tag_number(tag)); \
68 				return 0; \
69 			} \
70 		} \
71 		tags = (unsigned short *)((char *)tags + dlen); \
72 	} \
73 	return 1; \
74 }
75 #define NL_INTEGER(pn, pr, member) \
76 	case pn: /* D_ASSERT( tag_type(tag) == TT_INTEGER ); */ \
77 		arg->member = get_unaligned((int *)(tags));	\
78 		break;
79 #define NL_INT64(pn, pr, member) \
80 	case pn: /* D_ASSERT( tag_type(tag) == TT_INT64 ); */ \
81 		arg->member = get_unaligned((u64 *)(tags));	\
82 		break;
83 #define NL_BIT(pn, pr, member) \
84 	case pn: /* D_ASSERT( tag_type(tag) == TT_BIT ); */ \
85 		arg->member = *(char *)(tags) ? 1 : 0; \
86 		break;
87 #define NL_STRING(pn, pr, member, len) \
88 	case pn: /* D_ASSERT( tag_type(tag) == TT_STRING ); */ \
89 		if (dlen > len) { \
90 			dev_err(DEV, "arg too long: %s (%u wanted, max len: %u bytes)\n", \
91 				#member, dlen, (unsigned int)len); \
92 			return 0; \
93 		} \
94 		 arg->member ## _len = dlen; \
95 		 memcpy(arg->member, tags, min_t(size_t, dlen, len)); \
96 		 break;
97 #include <linux/drbd_nl.h>
98 
99 /* Generate the struct to tag_list functions */
100 #define NL_PACKET(name, number, fields) \
101 static unsigned short* \
102 name ## _to_tags(struct drbd_conf *mdev, \
103 	struct name *arg, unsigned short *tags) __attribute__ ((unused)); \
104 static unsigned short* \
105 name ## _to_tags(struct drbd_conf *mdev, \
106 	struct name *arg, unsigned short *tags) \
107 { \
108 	fields \
109 	return tags; \
110 }
111 
112 #define NL_INTEGER(pn, pr, member) \
113 	put_unaligned(pn | pr | TT_INTEGER, tags++);	\
114 	put_unaligned(sizeof(int), tags++);		\
115 	put_unaligned(arg->member, (int *)tags);	\
116 	tags = (unsigned short *)((char *)tags+sizeof(int));
117 #define NL_INT64(pn, pr, member) \
118 	put_unaligned(pn | pr | TT_INT64, tags++);	\
119 	put_unaligned(sizeof(u64), tags++);		\
120 	put_unaligned(arg->member, (u64 *)tags);	\
121 	tags = (unsigned short *)((char *)tags+sizeof(u64));
122 #define NL_BIT(pn, pr, member) \
123 	put_unaligned(pn | pr | TT_BIT, tags++);	\
124 	put_unaligned(sizeof(char), tags++);		\
125 	*(char *)tags = arg->member; \
126 	tags = (unsigned short *)((char *)tags+sizeof(char));
127 #define NL_STRING(pn, pr, member, len) \
128 	put_unaligned(pn | pr | TT_STRING, tags++);	\
129 	put_unaligned(arg->member ## _len, tags++);	\
130 	memcpy(tags, arg->member, arg->member ## _len); \
131 	tags = (unsigned short *)((char *)tags + arg->member ## _len);
132 #include <linux/drbd_nl.h>
133 
134 void drbd_bcast_ev_helper(struct drbd_conf *mdev, char *helper_name);
135 void drbd_nl_send_reply(struct cn_msg *, int);
136 
137 int drbd_khelper(struct drbd_conf *mdev, char *cmd)
138 {
139 	char *envp[] = { "HOME=/",
140 			"TERM=linux",
141 			"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
142 			NULL, /* Will be set to address family */
143 			NULL, /* Will be set to address */
144 			NULL };
145 
146 	char mb[12], af[20], ad[60], *afs;
147 	char *argv[] = {usermode_helper, cmd, mb, NULL };
148 	int ret;
149 
150 	snprintf(mb, 12, "minor-%d", mdev_to_minor(mdev));
151 
152 	if (get_net_conf(mdev)) {
153 		switch (((struct sockaddr *)mdev->net_conf->peer_addr)->sa_family) {
154 		case AF_INET6:
155 			afs = "ipv6";
156 			snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI6",
157 				 &((struct sockaddr_in6 *)mdev->net_conf->peer_addr)->sin6_addr);
158 			break;
159 		case AF_INET:
160 			afs = "ipv4";
161 			snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI4",
162 				 &((struct sockaddr_in *)mdev->net_conf->peer_addr)->sin_addr);
163 			break;
164 		default:
165 			afs = "ssocks";
166 			snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI4",
167 				 &((struct sockaddr_in *)mdev->net_conf->peer_addr)->sin_addr);
168 		}
169 		snprintf(af, 20, "DRBD_PEER_AF=%s", afs);
170 		envp[3]=af;
171 		envp[4]=ad;
172 		put_net_conf(mdev);
173 	}
174 
175 	/* The helper may take some time.
176 	 * write out any unsynced meta data changes now */
177 	drbd_md_sync(mdev);
178 
179 	dev_info(DEV, "helper command: %s %s %s\n", usermode_helper, cmd, mb);
180 
181 	drbd_bcast_ev_helper(mdev, cmd);
182 	ret = call_usermodehelper(usermode_helper, argv, envp, UMH_WAIT_PROC);
183 	if (ret)
184 		dev_warn(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
185 				usermode_helper, cmd, mb,
186 				(ret >> 8) & 0xff, ret);
187 	else
188 		dev_info(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
189 				usermode_helper, cmd, mb,
190 				(ret >> 8) & 0xff, ret);
191 
192 	if (ret < 0) /* Ignore any ERRNOs we got. */
193 		ret = 0;
194 
195 	return ret;
196 }
197 
198 enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev)
199 {
200 	char *ex_to_string;
201 	int r;
202 	enum drbd_disk_state nps;
203 	enum drbd_fencing_p fp;
204 
205 	D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
206 
207 	if (get_ldev_if_state(mdev, D_CONSISTENT)) {
208 		fp = mdev->ldev->dc.fencing;
209 		put_ldev(mdev);
210 	} else {
211 		dev_warn(DEV, "Not fencing peer, I'm not even Consistent myself.\n");
212 		nps = mdev->state.pdsk;
213 		goto out;
214 	}
215 
216 	r = drbd_khelper(mdev, "fence-peer");
217 
218 	switch ((r>>8) & 0xff) {
219 	case 3: /* peer is inconsistent */
220 		ex_to_string = "peer is inconsistent or worse";
221 		nps = D_INCONSISTENT;
222 		break;
223 	case 4: /* peer got outdated, or was already outdated */
224 		ex_to_string = "peer was fenced";
225 		nps = D_OUTDATED;
226 		break;
227 	case 5: /* peer was down */
228 		if (mdev->state.disk == D_UP_TO_DATE) {
229 			/* we will(have) create(d) a new UUID anyways... */
230 			ex_to_string = "peer is unreachable, assumed to be dead";
231 			nps = D_OUTDATED;
232 		} else {
233 			ex_to_string = "peer unreachable, doing nothing since disk != UpToDate";
234 			nps = mdev->state.pdsk;
235 		}
236 		break;
237 	case 6: /* Peer is primary, voluntarily outdate myself.
238 		 * This is useful when an unconnected R_SECONDARY is asked to
239 		 * become R_PRIMARY, but finds the other peer being active. */
240 		ex_to_string = "peer is active";
241 		dev_warn(DEV, "Peer is primary, outdating myself.\n");
242 		nps = D_UNKNOWN;
243 		_drbd_request_state(mdev, NS(disk, D_OUTDATED), CS_WAIT_COMPLETE);
244 		break;
245 	case 7:
246 		if (fp != FP_STONITH)
247 			dev_err(DEV, "fence-peer() = 7 && fencing != Stonith !!!\n");
248 		ex_to_string = "peer was stonithed";
249 		nps = D_OUTDATED;
250 		break;
251 	default:
252 		/* The script is broken ... */
253 		nps = D_UNKNOWN;
254 		dev_err(DEV, "fence-peer helper broken, returned %d\n", (r>>8)&0xff);
255 		return nps;
256 	}
257 
258 	dev_info(DEV, "fence-peer helper returned %d (%s)\n",
259 			(r>>8) & 0xff, ex_to_string);
260 
261 out:
262 	if (mdev->state.susp_fen && nps >= D_UNKNOWN) {
263 		/* The handler was not successful... unfreeze here, the
264 		   state engine can not unfreeze... */
265 		_drbd_request_state(mdev, NS(susp_fen, 0), CS_VERBOSE);
266 	}
267 
268 	return nps;
269 }
270 
271 static int _try_outdate_peer_async(void *data)
272 {
273 	struct drbd_conf *mdev = (struct drbd_conf *)data;
274 	enum drbd_disk_state nps;
275 	union drbd_state ns;
276 
277 	nps = drbd_try_outdate_peer(mdev);
278 
279 	/* Not using
280 	   drbd_request_state(mdev, NS(pdsk, nps));
281 	   here, because we might were able to re-establish the connection
282 	   in the meantime. This can only partially be solved in the state's
283 	   engine is_valid_state() and is_valid_state_transition()
284 	   functions.
285 
286 	   nps can be D_INCONSISTENT, D_OUTDATED or D_UNKNOWN.
287 	   pdsk == D_INCONSISTENT while conn >= C_CONNECTED is valid,
288 	   therefore we have to have the pre state change check here.
289 	*/
290 	spin_lock_irq(&mdev->req_lock);
291 	ns = mdev->state;
292 	if (ns.conn < C_WF_REPORT_PARAMS && !test_bit(STATE_SENT, &mdev->flags)) {
293 		ns.pdsk = nps;
294 		_drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
295 	}
296 	spin_unlock_irq(&mdev->req_lock);
297 
298 	return 0;
299 }
300 
301 void drbd_try_outdate_peer_async(struct drbd_conf *mdev)
302 {
303 	struct task_struct *opa;
304 
305 	opa = kthread_run(_try_outdate_peer_async, mdev, "drbd%d_a_helper", mdev_to_minor(mdev));
306 	if (IS_ERR(opa))
307 		dev_err(DEV, "out of mem, failed to invoke fence-peer helper\n");
308 }
309 
310 enum drbd_state_rv
311 drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, int force)
312 {
313 	const int max_tries = 4;
314 	enum drbd_state_rv rv = SS_UNKNOWN_ERROR;
315 	int try = 0;
316 	int forced = 0;
317 	union drbd_state mask, val;
318 	enum drbd_disk_state nps;
319 
320 	if (new_role == R_PRIMARY)
321 		request_ping(mdev); /* Detect a dead peer ASAP */
322 
323 	mutex_lock(&mdev->state_mutex);
324 
325 	mask.i = 0; mask.role = R_MASK;
326 	val.i  = 0; val.role  = new_role;
327 
328 	while (try++ < max_tries) {
329 		rv = _drbd_request_state(mdev, mask, val, CS_WAIT_COMPLETE);
330 
331 		/* in case we first succeeded to outdate,
332 		 * but now suddenly could establish a connection */
333 		if (rv == SS_CW_FAILED_BY_PEER && mask.pdsk != 0) {
334 			val.pdsk = 0;
335 			mask.pdsk = 0;
336 			continue;
337 		}
338 
339 		if (rv == SS_NO_UP_TO_DATE_DISK && force &&
340 		    (mdev->state.disk < D_UP_TO_DATE &&
341 		     mdev->state.disk >= D_INCONSISTENT)) {
342 			mask.disk = D_MASK;
343 			val.disk  = D_UP_TO_DATE;
344 			forced = 1;
345 			continue;
346 		}
347 
348 		if (rv == SS_NO_UP_TO_DATE_DISK &&
349 		    mdev->state.disk == D_CONSISTENT && mask.pdsk == 0) {
350 			D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
351 			nps = drbd_try_outdate_peer(mdev);
352 
353 			if (nps == D_OUTDATED || nps == D_INCONSISTENT) {
354 				val.disk = D_UP_TO_DATE;
355 				mask.disk = D_MASK;
356 			}
357 
358 			val.pdsk = nps;
359 			mask.pdsk = D_MASK;
360 
361 			continue;
362 		}
363 
364 		if (rv == SS_NOTHING_TO_DO)
365 			goto fail;
366 		if (rv == SS_PRIMARY_NOP && mask.pdsk == 0) {
367 			nps = drbd_try_outdate_peer(mdev);
368 
369 			if (force && nps > D_OUTDATED) {
370 				dev_warn(DEV, "Forced into split brain situation!\n");
371 				nps = D_OUTDATED;
372 			}
373 
374 			mask.pdsk = D_MASK;
375 			val.pdsk  = nps;
376 
377 			continue;
378 		}
379 		if (rv == SS_TWO_PRIMARIES) {
380 			/* Maybe the peer is detected as dead very soon...
381 			   retry at most once more in this case. */
382 			schedule_timeout_interruptible((mdev->net_conf->ping_timeo+1)*HZ/10);
383 			if (try < max_tries)
384 				try = max_tries - 1;
385 			continue;
386 		}
387 		if (rv < SS_SUCCESS) {
388 			rv = _drbd_request_state(mdev, mask, val,
389 						CS_VERBOSE + CS_WAIT_COMPLETE);
390 			if (rv < SS_SUCCESS)
391 				goto fail;
392 		}
393 		break;
394 	}
395 
396 	if (rv < SS_SUCCESS)
397 		goto fail;
398 
399 	if (forced)
400 		dev_warn(DEV, "Forced to consider local data as UpToDate!\n");
401 
402 	/* Wait until nothing is on the fly :) */
403 	wait_event(mdev->misc_wait, atomic_read(&mdev->ap_pending_cnt) == 0);
404 
405 	if (new_role == R_SECONDARY) {
406 		set_disk_ro(mdev->vdisk, true);
407 		if (get_ldev(mdev)) {
408 			mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
409 			put_ldev(mdev);
410 		}
411 	} else {
412 		if (get_net_conf(mdev)) {
413 			mdev->net_conf->want_lose = 0;
414 			put_net_conf(mdev);
415 		}
416 		set_disk_ro(mdev->vdisk, false);
417 		if (get_ldev(mdev)) {
418 			if (((mdev->state.conn < C_CONNECTED ||
419 			       mdev->state.pdsk <= D_FAILED)
420 			      && mdev->ldev->md.uuid[UI_BITMAP] == 0) || forced)
421 				drbd_uuid_new_current(mdev);
422 
423 			mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
424 			put_ldev(mdev);
425 		}
426 	}
427 
428 	/* writeout of activity log covered areas of the bitmap
429 	 * to stable storage done in after state change already */
430 
431 	if (mdev->state.conn >= C_WF_REPORT_PARAMS) {
432 		/* if this was forced, we should consider sync */
433 		if (forced)
434 			drbd_send_uuids(mdev);
435 		drbd_send_current_state(mdev);
436 	}
437 
438 	drbd_md_sync(mdev);
439 
440 	kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
441  fail:
442 	mutex_unlock(&mdev->state_mutex);
443 	return rv;
444 }
445 
446 static struct drbd_conf *ensure_mdev(int minor, int create)
447 {
448 	struct drbd_conf *mdev;
449 
450 	if (minor >= minor_count)
451 		return NULL;
452 
453 	mdev = minor_to_mdev(minor);
454 
455 	if (!mdev && create) {
456 		struct gendisk *disk = NULL;
457 		mdev = drbd_new_device(minor);
458 
459 		spin_lock_irq(&drbd_pp_lock);
460 		if (minor_table[minor] == NULL) {
461 			minor_table[minor] = mdev;
462 			disk = mdev->vdisk;
463 			mdev = NULL;
464 		} /* else: we lost the race */
465 		spin_unlock_irq(&drbd_pp_lock);
466 
467 		if (disk) /* we won the race above */
468 			/* in case we ever add a drbd_delete_device(),
469 			 * don't forget the del_gendisk! */
470 			add_disk(disk);
471 		else /* we lost the race above */
472 			drbd_free_mdev(mdev);
473 
474 		mdev = minor_to_mdev(minor);
475 	}
476 
477 	return mdev;
478 }
479 
480 static int drbd_nl_primary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
481 			   struct drbd_nl_cfg_reply *reply)
482 {
483 	struct primary primary_args;
484 
485 	memset(&primary_args, 0, sizeof(struct primary));
486 	if (!primary_from_tags(mdev, nlp->tag_list, &primary_args)) {
487 		reply->ret_code = ERR_MANDATORY_TAG;
488 		return 0;
489 	}
490 
491 	reply->ret_code =
492 		drbd_set_role(mdev, R_PRIMARY, primary_args.primary_force);
493 
494 	return 0;
495 }
496 
497 static int drbd_nl_secondary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
498 			     struct drbd_nl_cfg_reply *reply)
499 {
500 	reply->ret_code = drbd_set_role(mdev, R_SECONDARY, 0);
501 
502 	return 0;
503 }
504 
505 /* initializes the md.*_offset members, so we are able to find
506  * the on disk meta data */
507 static void drbd_md_set_sector_offsets(struct drbd_conf *mdev,
508 				       struct drbd_backing_dev *bdev)
509 {
510 	sector_t md_size_sect = 0;
511 	switch (bdev->dc.meta_dev_idx) {
512 	default:
513 		/* v07 style fixed size indexed meta data */
514 		bdev->md.md_size_sect = MD_RESERVED_SECT;
515 		bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
516 		bdev->md.al_offset = MD_AL_OFFSET;
517 		bdev->md.bm_offset = MD_BM_OFFSET;
518 		break;
519 	case DRBD_MD_INDEX_FLEX_EXT:
520 		/* just occupy the full device; unit: sectors */
521 		bdev->md.md_size_sect = drbd_get_capacity(bdev->md_bdev);
522 		bdev->md.md_offset = 0;
523 		bdev->md.al_offset = MD_AL_OFFSET;
524 		bdev->md.bm_offset = MD_BM_OFFSET;
525 		break;
526 	case DRBD_MD_INDEX_INTERNAL:
527 	case DRBD_MD_INDEX_FLEX_INT:
528 		bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
529 		/* al size is still fixed */
530 		bdev->md.al_offset = -MD_AL_MAX_SIZE;
531 		/* we need (slightly less than) ~ this much bitmap sectors: */
532 		md_size_sect = drbd_get_capacity(bdev->backing_bdev);
533 		md_size_sect = ALIGN(md_size_sect, BM_SECT_PER_EXT);
534 		md_size_sect = BM_SECT_TO_EXT(md_size_sect);
535 		md_size_sect = ALIGN(md_size_sect, 8);
536 
537 		/* plus the "drbd meta data super block",
538 		 * and the activity log; */
539 		md_size_sect += MD_BM_OFFSET;
540 
541 		bdev->md.md_size_sect = md_size_sect;
542 		/* bitmap offset is adjusted by 'super' block size */
543 		bdev->md.bm_offset   = -md_size_sect + MD_AL_OFFSET;
544 		break;
545 	}
546 }
547 
548 /* input size is expected to be in KB */
549 char *ppsize(char *buf, unsigned long long size)
550 {
551 	/* Needs 9 bytes at max including trailing NUL:
552 	 * -1ULL ==> "16384 EB" */
553 	static char units[] = { 'K', 'M', 'G', 'T', 'P', 'E' };
554 	int base = 0;
555 	while (size >= 10000 && base < sizeof(units)-1) {
556 		/* shift + round */
557 		size = (size >> 10) + !!(size & (1<<9));
558 		base++;
559 	}
560 	sprintf(buf, "%u %cB", (unsigned)size, units[base]);
561 
562 	return buf;
563 }
564 
565 /* there is still a theoretical deadlock when called from receiver
566  * on an D_INCONSISTENT R_PRIMARY:
567  *  remote READ does inc_ap_bio, receiver would need to receive answer
568  *  packet from remote to dec_ap_bio again.
569  *  receiver receive_sizes(), comes here,
570  *  waits for ap_bio_cnt == 0. -> deadlock.
571  * but this cannot happen, actually, because:
572  *  R_PRIMARY D_INCONSISTENT, and peer's disk is unreachable
573  *  (not connected, or bad/no disk on peer):
574  *  see drbd_fail_request_early, ap_bio_cnt is zero.
575  *  R_PRIMARY D_INCONSISTENT, and C_SYNC_TARGET:
576  *  peer may not initiate a resize.
577  */
578 void drbd_suspend_io(struct drbd_conf *mdev)
579 {
580 	set_bit(SUSPEND_IO, &mdev->flags);
581 	if (is_susp(mdev->state))
582 		return;
583 	wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
584 }
585 
586 void drbd_resume_io(struct drbd_conf *mdev)
587 {
588 	clear_bit(SUSPEND_IO, &mdev->flags);
589 	wake_up(&mdev->misc_wait);
590 }
591 
592 /**
593  * drbd_determine_dev_size() -  Sets the right device size obeying all constraints
594  * @mdev:	DRBD device.
595  *
596  * Returns 0 on success, negative return values indicate errors.
597  * You should call drbd_md_sync() after calling this function.
598  */
599 enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *mdev, enum dds_flags flags) __must_hold(local)
600 {
601 	sector_t prev_first_sect, prev_size; /* previous meta location */
602 	sector_t la_size;
603 	sector_t size;
604 	char ppb[10];
605 
606 	int md_moved, la_size_changed;
607 	enum determine_dev_size rv = unchanged;
608 
609 	/* race:
610 	 * application request passes inc_ap_bio,
611 	 * but then cannot get an AL-reference.
612 	 * this function later may wait on ap_bio_cnt == 0. -> deadlock.
613 	 *
614 	 * to avoid that:
615 	 * Suspend IO right here.
616 	 * still lock the act_log to not trigger ASSERTs there.
617 	 */
618 	drbd_suspend_io(mdev);
619 
620 	/* no wait necessary anymore, actually we could assert that */
621 	wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
622 
623 	prev_first_sect = drbd_md_first_sector(mdev->ldev);
624 	prev_size = mdev->ldev->md.md_size_sect;
625 	la_size = mdev->ldev->md.la_size_sect;
626 
627 	/* TODO: should only be some assert here, not (re)init... */
628 	drbd_md_set_sector_offsets(mdev, mdev->ldev);
629 
630 	size = drbd_new_dev_size(mdev, mdev->ldev, flags & DDSF_FORCED);
631 
632 	if (drbd_get_capacity(mdev->this_bdev) != size ||
633 	    drbd_bm_capacity(mdev) != size) {
634 		int err;
635 		err = drbd_bm_resize(mdev, size, !(flags & DDSF_NO_RESYNC));
636 		if (unlikely(err)) {
637 			/* currently there is only one error: ENOMEM! */
638 			size = drbd_bm_capacity(mdev)>>1;
639 			if (size == 0) {
640 				dev_err(DEV, "OUT OF MEMORY! "
641 				    "Could not allocate bitmap!\n");
642 			} else {
643 				dev_err(DEV, "BM resizing failed. "
644 				    "Leaving size unchanged at size = %lu KB\n",
645 				    (unsigned long)size);
646 			}
647 			rv = dev_size_error;
648 		}
649 		/* racy, see comments above. */
650 		drbd_set_my_capacity(mdev, size);
651 		mdev->ldev->md.la_size_sect = size;
652 		dev_info(DEV, "size = %s (%llu KB)\n", ppsize(ppb, size>>1),
653 		     (unsigned long long)size>>1);
654 	}
655 	if (rv == dev_size_error)
656 		goto out;
657 
658 	la_size_changed = (la_size != mdev->ldev->md.la_size_sect);
659 
660 	md_moved = prev_first_sect != drbd_md_first_sector(mdev->ldev)
661 		|| prev_size	   != mdev->ldev->md.md_size_sect;
662 
663 	if (la_size_changed || md_moved) {
664 		int err;
665 
666 		drbd_al_shrink(mdev); /* All extents inactive. */
667 		dev_info(DEV, "Writing the whole bitmap, %s\n",
668 			 la_size_changed && md_moved ? "size changed and md moved" :
669 			 la_size_changed ? "size changed" : "md moved");
670 		/* next line implicitly does drbd_suspend_io()+drbd_resume_io() */
671 		err = drbd_bitmap_io(mdev, &drbd_bm_write,
672 				"size changed", BM_LOCKED_MASK);
673 		if (err) {
674 			rv = dev_size_error;
675 			goto out;
676 		}
677 		drbd_md_mark_dirty(mdev);
678 	}
679 
680 	if (size > la_size)
681 		rv = grew;
682 	if (size < la_size)
683 		rv = shrunk;
684 out:
685 	lc_unlock(mdev->act_log);
686 	wake_up(&mdev->al_wait);
687 	drbd_resume_io(mdev);
688 
689 	return rv;
690 }
691 
692 sector_t
693 drbd_new_dev_size(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, int assume_peer_has_space)
694 {
695 	sector_t p_size = mdev->p_size;   /* partner's disk size. */
696 	sector_t la_size = bdev->md.la_size_sect; /* last agreed size. */
697 	sector_t m_size; /* my size */
698 	sector_t u_size = bdev->dc.disk_size; /* size requested by user. */
699 	sector_t size = 0;
700 
701 	m_size = drbd_get_max_capacity(bdev);
702 
703 	if (mdev->state.conn < C_CONNECTED && assume_peer_has_space) {
704 		dev_warn(DEV, "Resize while not connected was forced by the user!\n");
705 		p_size = m_size;
706 	}
707 
708 	if (p_size && m_size) {
709 		size = min_t(sector_t, p_size, m_size);
710 	} else {
711 		if (la_size) {
712 			size = la_size;
713 			if (m_size && m_size < size)
714 				size = m_size;
715 			if (p_size && p_size < size)
716 				size = p_size;
717 		} else {
718 			if (m_size)
719 				size = m_size;
720 			if (p_size)
721 				size = p_size;
722 		}
723 	}
724 
725 	if (size == 0)
726 		dev_err(DEV, "Both nodes diskless!\n");
727 
728 	if (u_size) {
729 		if (u_size > size)
730 			dev_err(DEV, "Requested disk size is too big (%lu > %lu)\n",
731 			    (unsigned long)u_size>>1, (unsigned long)size>>1);
732 		else
733 			size = u_size;
734 	}
735 
736 	return size;
737 }
738 
739 /**
740  * drbd_check_al_size() - Ensures that the AL is of the right size
741  * @mdev:	DRBD device.
742  *
743  * Returns -EBUSY if current al lru is still used, -ENOMEM when allocation
744  * failed, and 0 on success. You should call drbd_md_sync() after you called
745  * this function.
746  */
747 static int drbd_check_al_size(struct drbd_conf *mdev)
748 {
749 	struct lru_cache *n, *t;
750 	struct lc_element *e;
751 	unsigned int in_use;
752 	int i;
753 
754 	ERR_IF(mdev->sync_conf.al_extents < 7)
755 		mdev->sync_conf.al_extents = 127;
756 
757 	if (mdev->act_log &&
758 	    mdev->act_log->nr_elements == mdev->sync_conf.al_extents)
759 		return 0;
760 
761 	in_use = 0;
762 	t = mdev->act_log;
763 	n = lc_create("act_log", drbd_al_ext_cache,
764 		mdev->sync_conf.al_extents, sizeof(struct lc_element), 0);
765 
766 	if (n == NULL) {
767 		dev_err(DEV, "Cannot allocate act_log lru!\n");
768 		return -ENOMEM;
769 	}
770 	spin_lock_irq(&mdev->al_lock);
771 	if (t) {
772 		for (i = 0; i < t->nr_elements; i++) {
773 			e = lc_element_by_index(t, i);
774 			if (e->refcnt)
775 				dev_err(DEV, "refcnt(%d)==%d\n",
776 				    e->lc_number, e->refcnt);
777 			in_use += e->refcnt;
778 		}
779 	}
780 	if (!in_use)
781 		mdev->act_log = n;
782 	spin_unlock_irq(&mdev->al_lock);
783 	if (in_use) {
784 		dev_err(DEV, "Activity log still in use!\n");
785 		lc_destroy(n);
786 		return -EBUSY;
787 	} else {
788 		if (t)
789 			lc_destroy(t);
790 	}
791 	drbd_md_mark_dirty(mdev); /* we changed mdev->act_log->nr_elemens */
792 	return 0;
793 }
794 
795 static void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_bio_size)
796 {
797 	struct request_queue * const q = mdev->rq_queue;
798 	int max_hw_sectors = max_bio_size >> 9;
799 	int max_segments = 0;
800 
801 	if (get_ldev_if_state(mdev, D_ATTACHING)) {
802 		struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
803 
804 		max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9);
805 		max_segments = mdev->ldev->dc.max_bio_bvecs;
806 		put_ldev(mdev);
807 	}
808 
809 	blk_queue_logical_block_size(q, 512);
810 	blk_queue_max_hw_sectors(q, max_hw_sectors);
811 	/* This is the workaround for "bio would need to, but cannot, be split" */
812 	blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
813 	blk_queue_segment_boundary(q, PAGE_CACHE_SIZE-1);
814 
815 	if (get_ldev_if_state(mdev, D_ATTACHING)) {
816 		struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
817 
818 		blk_queue_stack_limits(q, b);
819 
820 		if (q->backing_dev_info.ra_pages != b->backing_dev_info.ra_pages) {
821 			dev_info(DEV, "Adjusting my ra_pages to backing device's (%lu -> %lu)\n",
822 				 q->backing_dev_info.ra_pages,
823 				 b->backing_dev_info.ra_pages);
824 			q->backing_dev_info.ra_pages = b->backing_dev_info.ra_pages;
825 		}
826 		put_ldev(mdev);
827 	}
828 }
829 
830 void drbd_reconsider_max_bio_size(struct drbd_conf *mdev)
831 {
832 	int now, new, local, peer;
833 
834 	now = queue_max_hw_sectors(mdev->rq_queue) << 9;
835 	local = mdev->local_max_bio_size; /* Eventually last known value, from volatile memory */
836 	peer = mdev->peer_max_bio_size; /* Eventually last known value, from meta data */
837 
838 	if (get_ldev_if_state(mdev, D_ATTACHING)) {
839 		local = queue_max_hw_sectors(mdev->ldev->backing_bdev->bd_disk->queue) << 9;
840 		mdev->local_max_bio_size = local;
841 		put_ldev(mdev);
842 	}
843 
844 	/* We may ignore peer limits if the peer is modern enough.
845 	   Because new from 8.3.8 onwards the peer can use multiple
846 	   BIOs for a single peer_request */
847 	if (mdev->state.conn >= C_CONNECTED) {
848 		if (mdev->agreed_pro_version < 94) {
849 			peer = min_t(int, mdev->peer_max_bio_size, DRBD_MAX_SIZE_H80_PACKET);
850 			/* Correct old drbd (up to 8.3.7) if it believes it can do more than 32KiB */
851 		} else if (mdev->agreed_pro_version == 94)
852 			peer = DRBD_MAX_SIZE_H80_PACKET;
853 		else /* drbd 8.3.8 onwards */
854 			peer = DRBD_MAX_BIO_SIZE;
855 	}
856 
857 	new = min_t(int, local, peer);
858 
859 	if (mdev->state.role == R_PRIMARY && new < now)
860 		dev_err(DEV, "ASSERT FAILED new < now; (%d < %d)\n", new, now);
861 
862 	if (new != now)
863 		dev_info(DEV, "max BIO size = %u\n", new);
864 
865 	drbd_setup_queue_param(mdev, new);
866 }
867 
868 /* serialize deconfig (worker exiting, doing cleanup)
869  * and reconfig (drbdsetup disk, drbdsetup net)
870  *
871  * Wait for a potentially exiting worker, then restart it,
872  * or start a new one.  Flush any pending work, there may still be an
873  * after_state_change queued.
874  */
875 static void drbd_reconfig_start(struct drbd_conf *mdev)
876 {
877 	wait_event(mdev->state_wait, !test_and_set_bit(CONFIG_PENDING, &mdev->flags));
878 	wait_event(mdev->state_wait, !test_bit(DEVICE_DYING, &mdev->flags));
879 	drbd_thread_start(&mdev->worker);
880 	drbd_flush_workqueue(mdev);
881 }
882 
883 /* if still unconfigured, stops worker again.
884  * if configured now, clears CONFIG_PENDING.
885  * wakes potential waiters */
886 static void drbd_reconfig_done(struct drbd_conf *mdev)
887 {
888 	spin_lock_irq(&mdev->req_lock);
889 	if (mdev->state.disk == D_DISKLESS &&
890 	    mdev->state.conn == C_STANDALONE &&
891 	    mdev->state.role == R_SECONDARY) {
892 		set_bit(DEVICE_DYING, &mdev->flags);
893 		drbd_thread_stop_nowait(&mdev->worker);
894 	} else
895 		clear_bit(CONFIG_PENDING, &mdev->flags);
896 	spin_unlock_irq(&mdev->req_lock);
897 	wake_up(&mdev->state_wait);
898 }
899 
900 /* Make sure IO is suspended before calling this function(). */
901 static void drbd_suspend_al(struct drbd_conf *mdev)
902 {
903 	int s = 0;
904 
905 	if (lc_try_lock(mdev->act_log)) {
906 		drbd_al_shrink(mdev);
907 		lc_unlock(mdev->act_log);
908 	} else {
909 		dev_warn(DEV, "Failed to lock al in drbd_suspend_al()\n");
910 		return;
911 	}
912 
913 	spin_lock_irq(&mdev->req_lock);
914 	if (mdev->state.conn < C_CONNECTED)
915 		s = !test_and_set_bit(AL_SUSPENDED, &mdev->flags);
916 
917 	spin_unlock_irq(&mdev->req_lock);
918 
919 	if (s)
920 		dev_info(DEV, "Suspended AL updates\n");
921 }
922 
923 /* does always return 0;
924  * interesting return code is in reply->ret_code */
925 static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
926 			     struct drbd_nl_cfg_reply *reply)
927 {
928 	enum drbd_ret_code retcode;
929 	enum determine_dev_size dd;
930 	sector_t max_possible_sectors;
931 	sector_t min_md_device_sectors;
932 	struct drbd_backing_dev *nbc = NULL; /* new_backing_conf */
933 	struct block_device *bdev;
934 	struct lru_cache *resync_lru = NULL;
935 	union drbd_state ns, os;
936 	enum drbd_state_rv rv;
937 	int cp_discovered = 0;
938 	int logical_block_size;
939 
940 	drbd_reconfig_start(mdev);
941 
942 	/* if you want to reconfigure, please tear down first */
943 	if (mdev->state.disk > D_DISKLESS) {
944 		retcode = ERR_DISK_CONFIGURED;
945 		goto fail;
946 	}
947 	/* It may just now have detached because of IO error.  Make sure
948 	 * drbd_ldev_destroy is done already, we may end up here very fast,
949 	 * e.g. if someone calls attach from the on-io-error handler,
950 	 * to realize a "hot spare" feature (not that I'd recommend that) */
951 	wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
952 
953 	/* allocation not in the IO path, cqueue thread context */
954 	nbc = kzalloc(sizeof(struct drbd_backing_dev), GFP_KERNEL);
955 	if (!nbc) {
956 		retcode = ERR_NOMEM;
957 		goto fail;
958 	}
959 
960 	nbc->dc.disk_size     = DRBD_DISK_SIZE_SECT_DEF;
961 	nbc->dc.on_io_error   = DRBD_ON_IO_ERROR_DEF;
962 	nbc->dc.fencing       = DRBD_FENCING_DEF;
963 	nbc->dc.max_bio_bvecs = DRBD_MAX_BIO_BVECS_DEF;
964 
965 	if (!disk_conf_from_tags(mdev, nlp->tag_list, &nbc->dc)) {
966 		retcode = ERR_MANDATORY_TAG;
967 		goto fail;
968 	}
969 
970 	if (nbc->dc.meta_dev_idx < DRBD_MD_INDEX_FLEX_INT) {
971 		retcode = ERR_MD_IDX_INVALID;
972 		goto fail;
973 	}
974 
975 	if (get_net_conf(mdev)) {
976 		int prot = mdev->net_conf->wire_protocol;
977 		put_net_conf(mdev);
978 		if (nbc->dc.fencing == FP_STONITH && prot == DRBD_PROT_A) {
979 			retcode = ERR_STONITH_AND_PROT_A;
980 			goto fail;
981 		}
982 	}
983 
984 	bdev = blkdev_get_by_path(nbc->dc.backing_dev,
985 				  FMODE_READ | FMODE_WRITE | FMODE_EXCL, mdev);
986 	if (IS_ERR(bdev)) {
987 		dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.backing_dev,
988 			PTR_ERR(bdev));
989 		retcode = ERR_OPEN_DISK;
990 		goto fail;
991 	}
992 	nbc->backing_bdev = bdev;
993 
994 	/*
995 	 * meta_dev_idx >= 0: external fixed size, possibly multiple
996 	 * drbd sharing one meta device.  TODO in that case, paranoia
997 	 * check that [md_bdev, meta_dev_idx] is not yet used by some
998 	 * other drbd minor!  (if you use drbd.conf + drbdadm, that
999 	 * should check it for you already; but if you don't, or
1000 	 * someone fooled it, we need to double check here)
1001 	 */
1002 	bdev = blkdev_get_by_path(nbc->dc.meta_dev,
1003 				  FMODE_READ | FMODE_WRITE | FMODE_EXCL,
1004 				  (nbc->dc.meta_dev_idx < 0) ?
1005 				  (void *)mdev : (void *)drbd_m_holder);
1006 	if (IS_ERR(bdev)) {
1007 		dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.meta_dev,
1008 			PTR_ERR(bdev));
1009 		retcode = ERR_OPEN_MD_DISK;
1010 		goto fail;
1011 	}
1012 	nbc->md_bdev = bdev;
1013 
1014 	if ((nbc->backing_bdev == nbc->md_bdev) !=
1015 	    (nbc->dc.meta_dev_idx == DRBD_MD_INDEX_INTERNAL ||
1016 	     nbc->dc.meta_dev_idx == DRBD_MD_INDEX_FLEX_INT)) {
1017 		retcode = ERR_MD_IDX_INVALID;
1018 		goto fail;
1019 	}
1020 
1021 	resync_lru = lc_create("resync", drbd_bm_ext_cache,
1022 			61, sizeof(struct bm_extent),
1023 			offsetof(struct bm_extent, lce));
1024 	if (!resync_lru) {
1025 		retcode = ERR_NOMEM;
1026 		goto fail;
1027 	}
1028 
1029 	/* RT - for drbd_get_max_capacity() DRBD_MD_INDEX_FLEX_INT */
1030 	drbd_md_set_sector_offsets(mdev, nbc);
1031 
1032 	if (drbd_get_max_capacity(nbc) < nbc->dc.disk_size) {
1033 		dev_err(DEV, "max capacity %llu smaller than disk size %llu\n",
1034 			(unsigned long long) drbd_get_max_capacity(nbc),
1035 			(unsigned long long) nbc->dc.disk_size);
1036 		retcode = ERR_DISK_TOO_SMALL;
1037 		goto fail;
1038 	}
1039 
1040 	if (nbc->dc.meta_dev_idx < 0) {
1041 		max_possible_sectors = DRBD_MAX_SECTORS_FLEX;
1042 		/* at least one MB, otherwise it does not make sense */
1043 		min_md_device_sectors = (2<<10);
1044 	} else {
1045 		max_possible_sectors = DRBD_MAX_SECTORS;
1046 		min_md_device_sectors = MD_RESERVED_SECT * (nbc->dc.meta_dev_idx + 1);
1047 	}
1048 
1049 	if (drbd_get_capacity(nbc->md_bdev) < min_md_device_sectors) {
1050 		retcode = ERR_MD_DISK_TOO_SMALL;
1051 		dev_warn(DEV, "refusing attach: md-device too small, "
1052 		     "at least %llu sectors needed for this meta-disk type\n",
1053 		     (unsigned long long) min_md_device_sectors);
1054 		goto fail;
1055 	}
1056 
1057 	/* Make sure the new disk is big enough
1058 	 * (we may currently be R_PRIMARY with no local disk...) */
1059 	if (drbd_get_max_capacity(nbc) <
1060 	    drbd_get_capacity(mdev->this_bdev)) {
1061 		retcode = ERR_DISK_TOO_SMALL;
1062 		goto fail;
1063 	}
1064 
1065 	nbc->known_size = drbd_get_capacity(nbc->backing_bdev);
1066 
1067 	if (nbc->known_size > max_possible_sectors) {
1068 		dev_warn(DEV, "==> truncating very big lower level device "
1069 			"to currently maximum possible %llu sectors <==\n",
1070 			(unsigned long long) max_possible_sectors);
1071 		if (nbc->dc.meta_dev_idx >= 0)
1072 			dev_warn(DEV, "==>> using internal or flexible "
1073 				      "meta data may help <<==\n");
1074 	}
1075 
1076 	drbd_suspend_io(mdev);
1077 	/* also wait for the last barrier ack. */
1078 	wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_pending_cnt) || is_susp(mdev->state));
1079 	/* and for any other previously queued work */
1080 	drbd_flush_workqueue(mdev);
1081 
1082 	rv = _drbd_request_state(mdev, NS(disk, D_ATTACHING), CS_VERBOSE);
1083 	retcode = rv;  /* FIXME: Type mismatch. */
1084 	drbd_resume_io(mdev);
1085 	if (rv < SS_SUCCESS)
1086 		goto fail;
1087 
1088 	if (!get_ldev_if_state(mdev, D_ATTACHING))
1089 		goto force_diskless;
1090 
1091 	drbd_md_set_sector_offsets(mdev, nbc);
1092 
1093 	/* allocate a second IO page if logical_block_size != 512 */
1094 	logical_block_size = bdev_logical_block_size(nbc->md_bdev);
1095 	if (logical_block_size == 0)
1096 		logical_block_size = MD_SECTOR_SIZE;
1097 
1098 	if (logical_block_size != MD_SECTOR_SIZE) {
1099 		if (!mdev->md_io_tmpp) {
1100 			struct page *page = alloc_page(GFP_NOIO);
1101 			if (!page)
1102 				goto force_diskless_dec;
1103 
1104 			dev_warn(DEV, "Meta data's bdev logical_block_size = %d != %d\n",
1105 			     logical_block_size, MD_SECTOR_SIZE);
1106 			dev_warn(DEV, "Workaround engaged (has performance impact).\n");
1107 
1108 			mdev->md_io_tmpp = page;
1109 		}
1110 	}
1111 
1112 	if (!mdev->bitmap) {
1113 		if (drbd_bm_init(mdev)) {
1114 			retcode = ERR_NOMEM;
1115 			goto force_diskless_dec;
1116 		}
1117 	}
1118 
1119 	retcode = drbd_md_read(mdev, nbc);
1120 	if (retcode != NO_ERROR)
1121 		goto force_diskless_dec;
1122 
1123 	if (mdev->state.conn < C_CONNECTED &&
1124 	    mdev->state.role == R_PRIMARY &&
1125 	    (mdev->ed_uuid & ~((u64)1)) != (nbc->md.uuid[UI_CURRENT] & ~((u64)1))) {
1126 		dev_err(DEV, "Can only attach to data with current UUID=%016llX\n",
1127 		    (unsigned long long)mdev->ed_uuid);
1128 		retcode = ERR_DATA_NOT_CURRENT;
1129 		goto force_diskless_dec;
1130 	}
1131 
1132 	/* Since we are diskless, fix the activity log first... */
1133 	if (drbd_check_al_size(mdev)) {
1134 		retcode = ERR_NOMEM;
1135 		goto force_diskless_dec;
1136 	}
1137 
1138 	/* Prevent shrinking of consistent devices ! */
1139 	if (drbd_md_test_flag(nbc, MDF_CONSISTENT) &&
1140 	    drbd_new_dev_size(mdev, nbc, 0) < nbc->md.la_size_sect) {
1141 		dev_warn(DEV, "refusing to truncate a consistent device\n");
1142 		retcode = ERR_DISK_TOO_SMALL;
1143 		goto force_diskless_dec;
1144 	}
1145 
1146 	if (!drbd_al_read_log(mdev, nbc)) {
1147 		retcode = ERR_IO_MD_DISK;
1148 		goto force_diskless_dec;
1149 	}
1150 
1151 	/* Reset the "barriers don't work" bits here, then force meta data to
1152 	 * be written, to ensure we determine if barriers are supported. */
1153 	if (nbc->dc.no_md_flush)
1154 		set_bit(MD_NO_FUA, &mdev->flags);
1155 	else
1156 		clear_bit(MD_NO_FUA, &mdev->flags);
1157 
1158 	/* Point of no return reached.
1159 	 * Devices and memory are no longer released by error cleanup below.
1160 	 * now mdev takes over responsibility, and the state engine should
1161 	 * clean it up somewhere.  */
1162 	D_ASSERT(mdev->ldev == NULL);
1163 	mdev->ldev = nbc;
1164 	mdev->resync = resync_lru;
1165 	nbc = NULL;
1166 	resync_lru = NULL;
1167 
1168 	mdev->write_ordering = WO_bdev_flush;
1169 	drbd_bump_write_ordering(mdev, WO_bdev_flush);
1170 
1171 	if (drbd_md_test_flag(mdev->ldev, MDF_CRASHED_PRIMARY))
1172 		set_bit(CRASHED_PRIMARY, &mdev->flags);
1173 	else
1174 		clear_bit(CRASHED_PRIMARY, &mdev->flags);
1175 
1176 	if (drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
1177 	    !(mdev->state.role == R_PRIMARY && mdev->state.susp_nod)) {
1178 		set_bit(CRASHED_PRIMARY, &mdev->flags);
1179 		cp_discovered = 1;
1180 	}
1181 
1182 	mdev->send_cnt = 0;
1183 	mdev->recv_cnt = 0;
1184 	mdev->read_cnt = 0;
1185 	mdev->writ_cnt = 0;
1186 
1187 	drbd_reconsider_max_bio_size(mdev);
1188 
1189 	/* If I am currently not R_PRIMARY,
1190 	 * but meta data primary indicator is set,
1191 	 * I just now recover from a hard crash,
1192 	 * and have been R_PRIMARY before that crash.
1193 	 *
1194 	 * Now, if I had no connection before that crash
1195 	 * (have been degraded R_PRIMARY), chances are that
1196 	 * I won't find my peer now either.
1197 	 *
1198 	 * In that case, and _only_ in that case,
1199 	 * we use the degr-wfc-timeout instead of the default,
1200 	 * so we can automatically recover from a crash of a
1201 	 * degraded but active "cluster" after a certain timeout.
1202 	 */
1203 	clear_bit(USE_DEGR_WFC_T, &mdev->flags);
1204 	if (mdev->state.role != R_PRIMARY &&
1205 	     drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
1206 	    !drbd_md_test_flag(mdev->ldev, MDF_CONNECTED_IND))
1207 		set_bit(USE_DEGR_WFC_T, &mdev->flags);
1208 
1209 	dd = drbd_determine_dev_size(mdev, 0);
1210 	if (dd == dev_size_error) {
1211 		retcode = ERR_NOMEM_BITMAP;
1212 		goto force_diskless_dec;
1213 	} else if (dd == grew)
1214 		set_bit(RESYNC_AFTER_NEG, &mdev->flags);
1215 
1216 	if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
1217 		dev_info(DEV, "Assuming that all blocks are out of sync "
1218 		     "(aka FullSync)\n");
1219 		if (drbd_bitmap_io(mdev, &drbd_bmio_set_n_write,
1220 			"set_n_write from attaching", BM_LOCKED_MASK)) {
1221 			retcode = ERR_IO_MD_DISK;
1222 			goto force_diskless_dec;
1223 		}
1224 	} else {
1225 		if (drbd_bitmap_io(mdev, &drbd_bm_read,
1226 			"read from attaching", BM_LOCKED_MASK) < 0) {
1227 			retcode = ERR_IO_MD_DISK;
1228 			goto force_diskless_dec;
1229 		}
1230 	}
1231 
1232 	if (cp_discovered) {
1233 		drbd_al_apply_to_bm(mdev);
1234 		if (drbd_bitmap_io(mdev, &drbd_bm_write,
1235 			"crashed primary apply AL", BM_LOCKED_MASK)) {
1236 			retcode = ERR_IO_MD_DISK;
1237 			goto force_diskless_dec;
1238 		}
1239 	}
1240 
1241 	if (_drbd_bm_total_weight(mdev) == drbd_bm_bits(mdev))
1242 		drbd_suspend_al(mdev); /* IO is still suspended here... */
1243 
1244 	spin_lock_irq(&mdev->req_lock);
1245 	os = mdev->state;
1246 	ns.i = os.i;
1247 	/* If MDF_CONSISTENT is not set go into inconsistent state,
1248 	   otherwise investigate MDF_WasUpToDate...
1249 	   If MDF_WAS_UP_TO_DATE is not set go into D_OUTDATED disk state,
1250 	   otherwise into D_CONSISTENT state.
1251 	*/
1252 	if (drbd_md_test_flag(mdev->ldev, MDF_CONSISTENT)) {
1253 		if (drbd_md_test_flag(mdev->ldev, MDF_WAS_UP_TO_DATE))
1254 			ns.disk = D_CONSISTENT;
1255 		else
1256 			ns.disk = D_OUTDATED;
1257 	} else {
1258 		ns.disk = D_INCONSISTENT;
1259 	}
1260 
1261 	if (drbd_md_test_flag(mdev->ldev, MDF_PEER_OUT_DATED))
1262 		ns.pdsk = D_OUTDATED;
1263 
1264 	if ( ns.disk == D_CONSISTENT &&
1265 	    (ns.pdsk == D_OUTDATED || mdev->ldev->dc.fencing == FP_DONT_CARE))
1266 		ns.disk = D_UP_TO_DATE;
1267 
1268 	/* All tests on MDF_PRIMARY_IND, MDF_CONNECTED_IND,
1269 	   MDF_CONSISTENT and MDF_WAS_UP_TO_DATE must happen before
1270 	   this point, because drbd_request_state() modifies these
1271 	   flags. */
1272 
1273 	/* In case we are C_CONNECTED postpone any decision on the new disk
1274 	   state after the negotiation phase. */
1275 	if (mdev->state.conn == C_CONNECTED) {
1276 		mdev->new_state_tmp.i = ns.i;
1277 		ns.i = os.i;
1278 		ns.disk = D_NEGOTIATING;
1279 
1280 		/* We expect to receive up-to-date UUIDs soon.
1281 		   To avoid a race in receive_state, free p_uuid while
1282 		   holding req_lock. I.e. atomic with the state change */
1283 		kfree(mdev->p_uuid);
1284 		mdev->p_uuid = NULL;
1285 	}
1286 
1287 	rv = _drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
1288 	ns = mdev->state;
1289 	spin_unlock_irq(&mdev->req_lock);
1290 
1291 	if (rv < SS_SUCCESS)
1292 		goto force_diskless_dec;
1293 
1294 	if (mdev->state.role == R_PRIMARY)
1295 		mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
1296 	else
1297 		mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
1298 
1299 	drbd_md_mark_dirty(mdev);
1300 	drbd_md_sync(mdev);
1301 
1302 	kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1303 	put_ldev(mdev);
1304 	reply->ret_code = retcode;
1305 	drbd_reconfig_done(mdev);
1306 	return 0;
1307 
1308  force_diskless_dec:
1309 	put_ldev(mdev);
1310  force_diskless:
1311 	drbd_force_state(mdev, NS(disk, D_FAILED));
1312 	drbd_md_sync(mdev);
1313  fail:
1314 	if (nbc) {
1315 		if (nbc->backing_bdev)
1316 			blkdev_put(nbc->backing_bdev,
1317 				   FMODE_READ | FMODE_WRITE | FMODE_EXCL);
1318 		if (nbc->md_bdev)
1319 			blkdev_put(nbc->md_bdev,
1320 				   FMODE_READ | FMODE_WRITE | FMODE_EXCL);
1321 		kfree(nbc);
1322 	}
1323 	lc_destroy(resync_lru);
1324 
1325 	reply->ret_code = retcode;
1326 	drbd_reconfig_done(mdev);
1327 	return 0;
1328 }
1329 
1330 /* Detaching the disk is a process in multiple stages.  First we need to lock
1331  * out application IO, in-flight IO, IO stuck in drbd_al_begin_io.
1332  * Then we transition to D_DISKLESS, and wait for put_ldev() to return all
1333  * internal references as well.
1334  * Only then we have finally detached. */
1335 static int drbd_nl_detach(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1336 			  struct drbd_nl_cfg_reply *reply)
1337 {
1338 	enum drbd_ret_code retcode;
1339 	int ret;
1340 	struct detach dt = {};
1341 
1342 	if (!detach_from_tags(mdev, nlp->tag_list, &dt)) {
1343 		reply->ret_code = ERR_MANDATORY_TAG;
1344 		goto out;
1345 	}
1346 
1347 	if (dt.detach_force) {
1348 		drbd_force_state(mdev, NS(disk, D_FAILED));
1349 		reply->ret_code = SS_SUCCESS;
1350 		goto out;
1351 	}
1352 
1353 	drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */
1354 	drbd_md_get_buffer(mdev); /* make sure there is no in-flight meta-data IO */
1355 	retcode = drbd_request_state(mdev, NS(disk, D_FAILED));
1356 	drbd_md_put_buffer(mdev);
1357 	/* D_FAILED will transition to DISKLESS. */
1358 	ret = wait_event_interruptible(mdev->misc_wait,
1359 			mdev->state.disk != D_FAILED);
1360 	drbd_resume_io(mdev);
1361 
1362 	if ((int)retcode == (int)SS_IS_DISKLESS)
1363 		retcode = SS_NOTHING_TO_DO;
1364 	if (ret)
1365 		retcode = ERR_INTR;
1366 	reply->ret_code = retcode;
1367 out:
1368 	return 0;
1369 }
1370 
1371 static int drbd_nl_net_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1372 			    struct drbd_nl_cfg_reply *reply)
1373 {
1374 	int i, ns;
1375 	enum drbd_ret_code retcode;
1376 	struct net_conf *new_conf = NULL;
1377 	struct crypto_hash *tfm = NULL;
1378 	struct crypto_hash *integrity_w_tfm = NULL;
1379 	struct crypto_hash *integrity_r_tfm = NULL;
1380 	struct hlist_head *new_tl_hash = NULL;
1381 	struct hlist_head *new_ee_hash = NULL;
1382 	struct drbd_conf *odev;
1383 	char hmac_name[CRYPTO_MAX_ALG_NAME];
1384 	void *int_dig_out = NULL;
1385 	void *int_dig_in = NULL;
1386 	void *int_dig_vv = NULL;
1387 	struct sockaddr *new_my_addr, *new_peer_addr, *taken_addr;
1388 
1389 	drbd_reconfig_start(mdev);
1390 
1391 	if (mdev->state.conn > C_STANDALONE) {
1392 		retcode = ERR_NET_CONFIGURED;
1393 		goto fail;
1394 	}
1395 
1396 	/* allocation not in the IO path, cqueue thread context */
1397 	new_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
1398 	if (!new_conf) {
1399 		retcode = ERR_NOMEM;
1400 		goto fail;
1401 	}
1402 
1403 	new_conf->timeout	   = DRBD_TIMEOUT_DEF;
1404 	new_conf->try_connect_int  = DRBD_CONNECT_INT_DEF;
1405 	new_conf->ping_int	   = DRBD_PING_INT_DEF;
1406 	new_conf->max_epoch_size   = DRBD_MAX_EPOCH_SIZE_DEF;
1407 	new_conf->max_buffers	   = DRBD_MAX_BUFFERS_DEF;
1408 	new_conf->unplug_watermark = DRBD_UNPLUG_WATERMARK_DEF;
1409 	new_conf->sndbuf_size	   = DRBD_SNDBUF_SIZE_DEF;
1410 	new_conf->rcvbuf_size	   = DRBD_RCVBUF_SIZE_DEF;
1411 	new_conf->ko_count	   = DRBD_KO_COUNT_DEF;
1412 	new_conf->after_sb_0p	   = DRBD_AFTER_SB_0P_DEF;
1413 	new_conf->after_sb_1p	   = DRBD_AFTER_SB_1P_DEF;
1414 	new_conf->after_sb_2p	   = DRBD_AFTER_SB_2P_DEF;
1415 	new_conf->want_lose	   = 0;
1416 	new_conf->two_primaries    = 0;
1417 	new_conf->wire_protocol    = DRBD_PROT_C;
1418 	new_conf->ping_timeo	   = DRBD_PING_TIMEO_DEF;
1419 	new_conf->rr_conflict	   = DRBD_RR_CONFLICT_DEF;
1420 	new_conf->on_congestion    = DRBD_ON_CONGESTION_DEF;
1421 	new_conf->cong_extents     = DRBD_CONG_EXTENTS_DEF;
1422 
1423 	if (!net_conf_from_tags(mdev, nlp->tag_list, new_conf)) {
1424 		retcode = ERR_MANDATORY_TAG;
1425 		goto fail;
1426 	}
1427 
1428 	if (new_conf->two_primaries
1429 	    && (new_conf->wire_protocol != DRBD_PROT_C)) {
1430 		retcode = ERR_NOT_PROTO_C;
1431 		goto fail;
1432 	}
1433 
1434 	if (get_ldev(mdev)) {
1435 		enum drbd_fencing_p fp = mdev->ldev->dc.fencing;
1436 		put_ldev(mdev);
1437 		if (new_conf->wire_protocol == DRBD_PROT_A && fp == FP_STONITH) {
1438 			retcode = ERR_STONITH_AND_PROT_A;
1439 			goto fail;
1440 		}
1441 	}
1442 
1443 	if (new_conf->on_congestion != OC_BLOCK && new_conf->wire_protocol != DRBD_PROT_A) {
1444 		retcode = ERR_CONG_NOT_PROTO_A;
1445 		goto fail;
1446 	}
1447 
1448 	if (mdev->state.role == R_PRIMARY && new_conf->want_lose) {
1449 		retcode = ERR_DISCARD;
1450 		goto fail;
1451 	}
1452 
1453 	retcode = NO_ERROR;
1454 
1455 	new_my_addr = (struct sockaddr *)&new_conf->my_addr;
1456 	new_peer_addr = (struct sockaddr *)&new_conf->peer_addr;
1457 	for (i = 0; i < minor_count; i++) {
1458 		odev = minor_to_mdev(i);
1459 		if (!odev || odev == mdev)
1460 			continue;
1461 		if (get_net_conf(odev)) {
1462 			taken_addr = (struct sockaddr *)&odev->net_conf->my_addr;
1463 			if (new_conf->my_addr_len == odev->net_conf->my_addr_len &&
1464 			    !memcmp(new_my_addr, taken_addr, new_conf->my_addr_len))
1465 				retcode = ERR_LOCAL_ADDR;
1466 
1467 			taken_addr = (struct sockaddr *)&odev->net_conf->peer_addr;
1468 			if (new_conf->peer_addr_len == odev->net_conf->peer_addr_len &&
1469 			    !memcmp(new_peer_addr, taken_addr, new_conf->peer_addr_len))
1470 				retcode = ERR_PEER_ADDR;
1471 
1472 			put_net_conf(odev);
1473 			if (retcode != NO_ERROR)
1474 				goto fail;
1475 		}
1476 	}
1477 
1478 	if (new_conf->cram_hmac_alg[0] != 0) {
1479 		snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",
1480 			new_conf->cram_hmac_alg);
1481 		tfm = crypto_alloc_hash(hmac_name, 0, CRYPTO_ALG_ASYNC);
1482 		if (IS_ERR(tfm)) {
1483 			tfm = NULL;
1484 			retcode = ERR_AUTH_ALG;
1485 			goto fail;
1486 		}
1487 
1488 		if (!drbd_crypto_is_hash(crypto_hash_tfm(tfm))) {
1489 			retcode = ERR_AUTH_ALG_ND;
1490 			goto fail;
1491 		}
1492 	}
1493 
1494 	if (new_conf->integrity_alg[0]) {
1495 		integrity_w_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1496 		if (IS_ERR(integrity_w_tfm)) {
1497 			integrity_w_tfm = NULL;
1498 			retcode=ERR_INTEGRITY_ALG;
1499 			goto fail;
1500 		}
1501 
1502 		if (!drbd_crypto_is_hash(crypto_hash_tfm(integrity_w_tfm))) {
1503 			retcode=ERR_INTEGRITY_ALG_ND;
1504 			goto fail;
1505 		}
1506 
1507 		integrity_r_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1508 		if (IS_ERR(integrity_r_tfm)) {
1509 			integrity_r_tfm = NULL;
1510 			retcode=ERR_INTEGRITY_ALG;
1511 			goto fail;
1512 		}
1513 	}
1514 
1515 	ns = new_conf->max_epoch_size/8;
1516 	if (mdev->tl_hash_s != ns) {
1517 		new_tl_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1518 		if (!new_tl_hash) {
1519 			retcode = ERR_NOMEM;
1520 			goto fail;
1521 		}
1522 	}
1523 
1524 	ns = new_conf->max_buffers/8;
1525 	if (new_conf->two_primaries && (mdev->ee_hash_s != ns)) {
1526 		new_ee_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1527 		if (!new_ee_hash) {
1528 			retcode = ERR_NOMEM;
1529 			goto fail;
1530 		}
1531 	}
1532 
1533 	((char *)new_conf->shared_secret)[SHARED_SECRET_MAX-1] = 0;
1534 
1535 	if (integrity_w_tfm) {
1536 		i = crypto_hash_digestsize(integrity_w_tfm);
1537 		int_dig_out = kmalloc(i, GFP_KERNEL);
1538 		if (!int_dig_out) {
1539 			retcode = ERR_NOMEM;
1540 			goto fail;
1541 		}
1542 		int_dig_in = kmalloc(i, GFP_KERNEL);
1543 		if (!int_dig_in) {
1544 			retcode = ERR_NOMEM;
1545 			goto fail;
1546 		}
1547 		int_dig_vv = kmalloc(i, GFP_KERNEL);
1548 		if (!int_dig_vv) {
1549 			retcode = ERR_NOMEM;
1550 			goto fail;
1551 		}
1552 	}
1553 
1554 	if (!mdev->bitmap) {
1555 		if(drbd_bm_init(mdev)) {
1556 			retcode = ERR_NOMEM;
1557 			goto fail;
1558 		}
1559 	}
1560 
1561 	drbd_flush_workqueue(mdev);
1562 	spin_lock_irq(&mdev->req_lock);
1563 	if (mdev->net_conf != NULL) {
1564 		retcode = ERR_NET_CONFIGURED;
1565 		spin_unlock_irq(&mdev->req_lock);
1566 		goto fail;
1567 	}
1568 	mdev->net_conf = new_conf;
1569 
1570 	mdev->send_cnt = 0;
1571 	mdev->recv_cnt = 0;
1572 
1573 	if (new_tl_hash) {
1574 		kfree(mdev->tl_hash);
1575 		mdev->tl_hash_s = mdev->net_conf->max_epoch_size/8;
1576 		mdev->tl_hash = new_tl_hash;
1577 	}
1578 
1579 	if (new_ee_hash) {
1580 		kfree(mdev->ee_hash);
1581 		mdev->ee_hash_s = mdev->net_conf->max_buffers/8;
1582 		mdev->ee_hash = new_ee_hash;
1583 	}
1584 
1585 	crypto_free_hash(mdev->cram_hmac_tfm);
1586 	mdev->cram_hmac_tfm = tfm;
1587 
1588 	crypto_free_hash(mdev->integrity_w_tfm);
1589 	mdev->integrity_w_tfm = integrity_w_tfm;
1590 
1591 	crypto_free_hash(mdev->integrity_r_tfm);
1592 	mdev->integrity_r_tfm = integrity_r_tfm;
1593 
1594 	kfree(mdev->int_dig_out);
1595 	kfree(mdev->int_dig_in);
1596 	kfree(mdev->int_dig_vv);
1597 	mdev->int_dig_out=int_dig_out;
1598 	mdev->int_dig_in=int_dig_in;
1599 	mdev->int_dig_vv=int_dig_vv;
1600 	retcode = _drbd_set_state(_NS(mdev, conn, C_UNCONNECTED), CS_VERBOSE, NULL);
1601 	spin_unlock_irq(&mdev->req_lock);
1602 
1603 	kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1604 	reply->ret_code = retcode;
1605 	drbd_reconfig_done(mdev);
1606 	return 0;
1607 
1608 fail:
1609 	kfree(int_dig_out);
1610 	kfree(int_dig_in);
1611 	kfree(int_dig_vv);
1612 	crypto_free_hash(tfm);
1613 	crypto_free_hash(integrity_w_tfm);
1614 	crypto_free_hash(integrity_r_tfm);
1615 	kfree(new_tl_hash);
1616 	kfree(new_ee_hash);
1617 	kfree(new_conf);
1618 
1619 	reply->ret_code = retcode;
1620 	drbd_reconfig_done(mdev);
1621 	return 0;
1622 }
1623 
1624 static int drbd_nl_disconnect(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1625 			      struct drbd_nl_cfg_reply *reply)
1626 {
1627 	int retcode;
1628 	struct disconnect dc;
1629 
1630 	memset(&dc, 0, sizeof(struct disconnect));
1631 	if (!disconnect_from_tags(mdev, nlp->tag_list, &dc)) {
1632 		retcode = ERR_MANDATORY_TAG;
1633 		goto fail;
1634 	}
1635 
1636 	if (dc.force) {
1637 		spin_lock_irq(&mdev->req_lock);
1638 		if (mdev->state.conn >= C_WF_CONNECTION)
1639 			_drbd_set_state(_NS(mdev, conn, C_DISCONNECTING), CS_HARD, NULL);
1640 		spin_unlock_irq(&mdev->req_lock);
1641 		goto done;
1642 	}
1643 
1644 	retcode = _drbd_request_state(mdev, NS(conn, C_DISCONNECTING), CS_ORDERED);
1645 
1646 	if (retcode == SS_NOTHING_TO_DO)
1647 		goto done;
1648 	else if (retcode == SS_ALREADY_STANDALONE)
1649 		goto done;
1650 	else if (retcode == SS_PRIMARY_NOP) {
1651 		/* Our statche checking code wants to see the peer outdated. */
1652 		retcode = drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1653 						      pdsk, D_OUTDATED));
1654 	} else if (retcode == SS_CW_FAILED_BY_PEER) {
1655 		/* The peer probably wants to see us outdated. */
1656 		retcode = _drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1657 							disk, D_OUTDATED),
1658 					      CS_ORDERED);
1659 		if (retcode == SS_IS_DISKLESS || retcode == SS_LOWER_THAN_OUTDATED) {
1660 			drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
1661 			retcode = SS_SUCCESS;
1662 		}
1663 	}
1664 
1665 	if (retcode < SS_SUCCESS)
1666 		goto fail;
1667 
1668 	if (wait_event_interruptible(mdev->state_wait,
1669 				     mdev->state.conn != C_DISCONNECTING)) {
1670 		/* Do not test for mdev->state.conn == C_STANDALONE, since
1671 		   someone else might connect us in the mean time! */
1672 		retcode = ERR_INTR;
1673 		goto fail;
1674 	}
1675 
1676  done:
1677 	retcode = NO_ERROR;
1678  fail:
1679 	drbd_md_sync(mdev);
1680 	reply->ret_code = retcode;
1681 	return 0;
1682 }
1683 
1684 void resync_after_online_grow(struct drbd_conf *mdev)
1685 {
1686 	int iass; /* I am sync source */
1687 
1688 	dev_info(DEV, "Resync of new storage after online grow\n");
1689 	if (mdev->state.role != mdev->state.peer)
1690 		iass = (mdev->state.role == R_PRIMARY);
1691 	else
1692 		iass = test_bit(DISCARD_CONCURRENT, &mdev->flags);
1693 
1694 	if (iass)
1695 		drbd_start_resync(mdev, C_SYNC_SOURCE);
1696 	else
1697 		_drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE + CS_SERIALIZE);
1698 }
1699 
1700 static int drbd_nl_resize(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1701 			  struct drbd_nl_cfg_reply *reply)
1702 {
1703 	struct resize rs;
1704 	int retcode = NO_ERROR;
1705 	enum determine_dev_size dd;
1706 	enum dds_flags ddsf;
1707 
1708 	memset(&rs, 0, sizeof(struct resize));
1709 	if (!resize_from_tags(mdev, nlp->tag_list, &rs)) {
1710 		retcode = ERR_MANDATORY_TAG;
1711 		goto fail;
1712 	}
1713 
1714 	if (mdev->state.conn > C_CONNECTED) {
1715 		retcode = ERR_RESIZE_RESYNC;
1716 		goto fail;
1717 	}
1718 
1719 	if (mdev->state.role == R_SECONDARY &&
1720 	    mdev->state.peer == R_SECONDARY) {
1721 		retcode = ERR_NO_PRIMARY;
1722 		goto fail;
1723 	}
1724 
1725 	if (!get_ldev(mdev)) {
1726 		retcode = ERR_NO_DISK;
1727 		goto fail;
1728 	}
1729 
1730 	if (rs.no_resync && mdev->agreed_pro_version < 93) {
1731 		retcode = ERR_NEED_APV_93;
1732 		goto fail_ldev;
1733 	}
1734 
1735 	if (mdev->ldev->known_size != drbd_get_capacity(mdev->ldev->backing_bdev))
1736 		mdev->ldev->known_size = drbd_get_capacity(mdev->ldev->backing_bdev);
1737 
1738 	mdev->ldev->dc.disk_size = (sector_t)rs.resize_size;
1739 	ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
1740 	dd = drbd_determine_dev_size(mdev, ddsf);
1741 	drbd_md_sync(mdev);
1742 	put_ldev(mdev);
1743 	if (dd == dev_size_error) {
1744 		retcode = ERR_NOMEM_BITMAP;
1745 		goto fail;
1746 	}
1747 
1748 	if (mdev->state.conn == C_CONNECTED) {
1749 		if (dd == grew)
1750 			set_bit(RESIZE_PENDING, &mdev->flags);
1751 
1752 		drbd_send_uuids(mdev);
1753 		drbd_send_sizes(mdev, 1, ddsf);
1754 	}
1755 
1756  fail:
1757 	reply->ret_code = retcode;
1758 	return 0;
1759 
1760  fail_ldev:
1761 	put_ldev(mdev);
1762 	goto fail;
1763 }
1764 
1765 static int drbd_nl_syncer_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1766 			       struct drbd_nl_cfg_reply *reply)
1767 {
1768 	int retcode = NO_ERROR;
1769 	int err;
1770 	int ovr; /* online verify running */
1771 	int rsr; /* re-sync running */
1772 	struct crypto_hash *verify_tfm = NULL;
1773 	struct crypto_hash *csums_tfm = NULL;
1774 	struct syncer_conf sc;
1775 	cpumask_var_t new_cpu_mask;
1776 	int *rs_plan_s = NULL;
1777 	int fifo_size;
1778 
1779 	if (!zalloc_cpumask_var(&new_cpu_mask, GFP_KERNEL)) {
1780 		retcode = ERR_NOMEM;
1781 		goto fail;
1782 	}
1783 
1784 	if (nlp->flags & DRBD_NL_SET_DEFAULTS) {
1785 		memset(&sc, 0, sizeof(struct syncer_conf));
1786 		sc.rate       = DRBD_RATE_DEF;
1787 		sc.after      = DRBD_AFTER_DEF;
1788 		sc.al_extents = DRBD_AL_EXTENTS_DEF;
1789 		sc.on_no_data  = DRBD_ON_NO_DATA_DEF;
1790 		sc.c_plan_ahead = DRBD_C_PLAN_AHEAD_DEF;
1791 		sc.c_delay_target = DRBD_C_DELAY_TARGET_DEF;
1792 		sc.c_fill_target = DRBD_C_FILL_TARGET_DEF;
1793 		sc.c_max_rate = DRBD_C_MAX_RATE_DEF;
1794 		sc.c_min_rate = DRBD_C_MIN_RATE_DEF;
1795 	} else
1796 		memcpy(&sc, &mdev->sync_conf, sizeof(struct syncer_conf));
1797 
1798 	if (!syncer_conf_from_tags(mdev, nlp->tag_list, &sc)) {
1799 		retcode = ERR_MANDATORY_TAG;
1800 		goto fail;
1801 	}
1802 
1803 	/* re-sync running */
1804 	rsr = (	mdev->state.conn == C_SYNC_SOURCE ||
1805 		mdev->state.conn == C_SYNC_TARGET ||
1806 		mdev->state.conn == C_PAUSED_SYNC_S ||
1807 		mdev->state.conn == C_PAUSED_SYNC_T );
1808 
1809 	if (rsr && strcmp(sc.csums_alg, mdev->sync_conf.csums_alg)) {
1810 		retcode = ERR_CSUMS_RESYNC_RUNNING;
1811 		goto fail;
1812 	}
1813 
1814 	if (!rsr && sc.csums_alg[0]) {
1815 		csums_tfm = crypto_alloc_hash(sc.csums_alg, 0, CRYPTO_ALG_ASYNC);
1816 		if (IS_ERR(csums_tfm)) {
1817 			csums_tfm = NULL;
1818 			retcode = ERR_CSUMS_ALG;
1819 			goto fail;
1820 		}
1821 
1822 		if (!drbd_crypto_is_hash(crypto_hash_tfm(csums_tfm))) {
1823 			retcode = ERR_CSUMS_ALG_ND;
1824 			goto fail;
1825 		}
1826 	}
1827 
1828 	/* online verify running */
1829 	ovr = (mdev->state.conn == C_VERIFY_S || mdev->state.conn == C_VERIFY_T);
1830 
1831 	if (ovr) {
1832 		if (strcmp(sc.verify_alg, mdev->sync_conf.verify_alg)) {
1833 			retcode = ERR_VERIFY_RUNNING;
1834 			goto fail;
1835 		}
1836 	}
1837 
1838 	if (!ovr && sc.verify_alg[0]) {
1839 		verify_tfm = crypto_alloc_hash(sc.verify_alg, 0, CRYPTO_ALG_ASYNC);
1840 		if (IS_ERR(verify_tfm)) {
1841 			verify_tfm = NULL;
1842 			retcode = ERR_VERIFY_ALG;
1843 			goto fail;
1844 		}
1845 
1846 		if (!drbd_crypto_is_hash(crypto_hash_tfm(verify_tfm))) {
1847 			retcode = ERR_VERIFY_ALG_ND;
1848 			goto fail;
1849 		}
1850 	}
1851 
1852 	/* silently ignore cpu mask on UP kernel */
1853 	if (nr_cpu_ids > 1 && sc.cpu_mask[0] != 0) {
1854 		err = bitmap_parse(sc.cpu_mask, 32,
1855 				cpumask_bits(new_cpu_mask), nr_cpu_ids);
1856 		if (err) {
1857 			dev_warn(DEV, "bitmap_parse() failed with %d\n", err);
1858 			retcode = ERR_CPU_MASK_PARSE;
1859 			goto fail;
1860 		}
1861 	}
1862 
1863 	ERR_IF (sc.rate < 1) sc.rate = 1;
1864 	ERR_IF (sc.al_extents < 7) sc.al_extents = 127; /* arbitrary minimum */
1865 #define AL_MAX ((MD_AL_MAX_SIZE-1) * AL_EXTENTS_PT)
1866 	if (sc.al_extents > AL_MAX) {
1867 		dev_err(DEV, "sc.al_extents > %d\n", AL_MAX);
1868 		sc.al_extents = AL_MAX;
1869 	}
1870 #undef AL_MAX
1871 
1872 	/* to avoid spurious errors when configuring minors before configuring
1873 	 * the minors they depend on: if necessary, first create the minor we
1874 	 * depend on */
1875 	if (sc.after >= 0)
1876 		ensure_mdev(sc.after, 1);
1877 
1878 	/* most sanity checks done, try to assign the new sync-after
1879 	 * dependency.  need to hold the global lock in there,
1880 	 * to avoid a race in the dependency loop check. */
1881 	retcode = drbd_alter_sa(mdev, sc.after);
1882 	if (retcode != NO_ERROR)
1883 		goto fail;
1884 
1885 	fifo_size = (sc.c_plan_ahead * 10 * SLEEP_TIME) / HZ;
1886 	if (fifo_size != mdev->rs_plan_s.size && fifo_size > 0) {
1887 		rs_plan_s   = kzalloc(sizeof(int) * fifo_size, GFP_KERNEL);
1888 		if (!rs_plan_s) {
1889 			dev_err(DEV, "kmalloc of fifo_buffer failed");
1890 			retcode = ERR_NOMEM;
1891 			goto fail;
1892 		}
1893 	}
1894 
1895 	/* ok, assign the rest of it as well.
1896 	 * lock against receive_SyncParam() */
1897 	spin_lock(&mdev->peer_seq_lock);
1898 	mdev->sync_conf = sc;
1899 
1900 	if (!rsr) {
1901 		crypto_free_hash(mdev->csums_tfm);
1902 		mdev->csums_tfm = csums_tfm;
1903 		csums_tfm = NULL;
1904 	}
1905 
1906 	if (!ovr) {
1907 		crypto_free_hash(mdev->verify_tfm);
1908 		mdev->verify_tfm = verify_tfm;
1909 		verify_tfm = NULL;
1910 	}
1911 
1912 	if (fifo_size != mdev->rs_plan_s.size) {
1913 		kfree(mdev->rs_plan_s.values);
1914 		mdev->rs_plan_s.values = rs_plan_s;
1915 		mdev->rs_plan_s.size   = fifo_size;
1916 		mdev->rs_planed = 0;
1917 		rs_plan_s = NULL;
1918 	}
1919 
1920 	spin_unlock(&mdev->peer_seq_lock);
1921 
1922 	if (get_ldev(mdev)) {
1923 		wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
1924 		drbd_al_shrink(mdev);
1925 		err = drbd_check_al_size(mdev);
1926 		lc_unlock(mdev->act_log);
1927 		wake_up(&mdev->al_wait);
1928 
1929 		put_ldev(mdev);
1930 		drbd_md_sync(mdev);
1931 
1932 		if (err) {
1933 			retcode = ERR_NOMEM;
1934 			goto fail;
1935 		}
1936 	}
1937 
1938 	if (mdev->state.conn >= C_CONNECTED)
1939 		drbd_send_sync_param(mdev, &sc);
1940 
1941 	if (!cpumask_equal(mdev->cpu_mask, new_cpu_mask)) {
1942 		cpumask_copy(mdev->cpu_mask, new_cpu_mask);
1943 		drbd_calc_cpu_mask(mdev);
1944 		mdev->receiver.reset_cpu_mask = 1;
1945 		mdev->asender.reset_cpu_mask = 1;
1946 		mdev->worker.reset_cpu_mask = 1;
1947 	}
1948 
1949 	kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1950 fail:
1951 	kfree(rs_plan_s);
1952 	free_cpumask_var(new_cpu_mask);
1953 	crypto_free_hash(csums_tfm);
1954 	crypto_free_hash(verify_tfm);
1955 	reply->ret_code = retcode;
1956 	return 0;
1957 }
1958 
1959 static int drbd_nl_invalidate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1960 			      struct drbd_nl_cfg_reply *reply)
1961 {
1962 	int retcode;
1963 
1964 	/* If there is still bitmap IO pending, probably because of a previous
1965 	 * resync just being finished, wait for it before requesting a new resync. */
1966 	drbd_suspend_io(mdev);
1967 	wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
1968 
1969 	retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T), CS_ORDERED);
1970 
1971 	if (retcode < SS_SUCCESS && retcode != SS_NEED_CONNECTION)
1972 		retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1973 
1974 	while (retcode == SS_NEED_CONNECTION) {
1975 		spin_lock_irq(&mdev->req_lock);
1976 		if (mdev->state.conn < C_CONNECTED)
1977 			retcode = _drbd_set_state(_NS(mdev, disk, D_INCONSISTENT), CS_VERBOSE, NULL);
1978 		spin_unlock_irq(&mdev->req_lock);
1979 
1980 		if (retcode != SS_NEED_CONNECTION)
1981 			break;
1982 
1983 		retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1984 	}
1985 	drbd_resume_io(mdev);
1986 
1987 	reply->ret_code = retcode;
1988 	return 0;
1989 }
1990 
1991 static int drbd_bmio_set_susp_al(struct drbd_conf *mdev)
1992 {
1993 	int rv;
1994 
1995 	rv = drbd_bmio_set_n_write(mdev);
1996 	drbd_suspend_al(mdev);
1997 	return rv;
1998 }
1999 
2000 static int drbd_nl_invalidate_peer(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2001 				   struct drbd_nl_cfg_reply *reply)
2002 {
2003 	int retcode;
2004 
2005 	/* If there is still bitmap IO pending, probably because of a previous
2006 	 * resync just being finished, wait for it before requesting a new resync. */
2007 	drbd_suspend_io(mdev);
2008 	wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
2009 
2010 	retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S), CS_ORDERED);
2011 
2012 	if (retcode < SS_SUCCESS) {
2013 		if (retcode == SS_NEED_CONNECTION && mdev->state.role == R_PRIMARY) {
2014 			/* The peer will get a resync upon connect anyways. Just make that
2015 			   into a full resync. */
2016 			retcode = drbd_request_state(mdev, NS(pdsk, D_INCONSISTENT));
2017 			if (retcode >= SS_SUCCESS) {
2018 				if (drbd_bitmap_io(mdev, &drbd_bmio_set_susp_al,
2019 					"set_n_write from invalidate_peer",
2020 					BM_LOCKED_SET_ALLOWED))
2021 					retcode = ERR_IO_MD_DISK;
2022 			}
2023 		} else
2024 			retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S));
2025 	}
2026 	drbd_resume_io(mdev);
2027 
2028 	reply->ret_code = retcode;
2029 	return 0;
2030 }
2031 
2032 static int drbd_nl_pause_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2033 			      struct drbd_nl_cfg_reply *reply)
2034 {
2035 	int retcode = NO_ERROR;
2036 
2037 	if (drbd_request_state(mdev, NS(user_isp, 1)) == SS_NOTHING_TO_DO)
2038 		retcode = ERR_PAUSE_IS_SET;
2039 
2040 	reply->ret_code = retcode;
2041 	return 0;
2042 }
2043 
2044 static int drbd_nl_resume_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2045 			       struct drbd_nl_cfg_reply *reply)
2046 {
2047 	int retcode = NO_ERROR;
2048 	union drbd_state s;
2049 
2050 	if (drbd_request_state(mdev, NS(user_isp, 0)) == SS_NOTHING_TO_DO) {
2051 		s = mdev->state;
2052 		if (s.conn == C_PAUSED_SYNC_S || s.conn == C_PAUSED_SYNC_T) {
2053 			retcode = s.aftr_isp ? ERR_PIC_AFTER_DEP :
2054 				  s.peer_isp ? ERR_PIC_PEER_DEP : ERR_PAUSE_IS_CLEAR;
2055 		} else {
2056 			retcode = ERR_PAUSE_IS_CLEAR;
2057 		}
2058 	}
2059 
2060 	reply->ret_code = retcode;
2061 	return 0;
2062 }
2063 
2064 static int drbd_nl_suspend_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2065 			      struct drbd_nl_cfg_reply *reply)
2066 {
2067 	reply->ret_code = drbd_request_state(mdev, NS(susp, 1));
2068 
2069 	return 0;
2070 }
2071 
2072 static int drbd_nl_resume_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2073 			     struct drbd_nl_cfg_reply *reply)
2074 {
2075 	if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
2076 		drbd_uuid_new_current(mdev);
2077 		clear_bit(NEW_CUR_UUID, &mdev->flags);
2078 	}
2079 	drbd_suspend_io(mdev);
2080 	reply->ret_code = drbd_request_state(mdev, NS3(susp, 0, susp_nod, 0, susp_fen, 0));
2081 	if (reply->ret_code == SS_SUCCESS) {
2082 		if (mdev->state.conn < C_CONNECTED)
2083 			tl_clear(mdev);
2084 		if (mdev->state.disk == D_DISKLESS || mdev->state.disk == D_FAILED)
2085 			tl_restart(mdev, fail_frozen_disk_io);
2086 	}
2087 	drbd_resume_io(mdev);
2088 
2089 	return 0;
2090 }
2091 
2092 static int drbd_nl_outdate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2093 			   struct drbd_nl_cfg_reply *reply)
2094 {
2095 	reply->ret_code = drbd_request_state(mdev, NS(disk, D_OUTDATED));
2096 	return 0;
2097 }
2098 
2099 static int drbd_nl_get_config(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2100 			   struct drbd_nl_cfg_reply *reply)
2101 {
2102 	unsigned short *tl;
2103 
2104 	tl = reply->tag_list;
2105 
2106 	if (get_ldev(mdev)) {
2107 		tl = disk_conf_to_tags(mdev, &mdev->ldev->dc, tl);
2108 		put_ldev(mdev);
2109 	}
2110 
2111 	if (get_net_conf(mdev)) {
2112 		tl = net_conf_to_tags(mdev, mdev->net_conf, tl);
2113 		put_net_conf(mdev);
2114 	}
2115 	tl = syncer_conf_to_tags(mdev, &mdev->sync_conf, tl);
2116 
2117 	put_unaligned(TT_END, tl++); /* Close the tag list */
2118 
2119 	return (int)((char *)tl - (char *)reply->tag_list);
2120 }
2121 
2122 static int drbd_nl_get_state(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2123 			     struct drbd_nl_cfg_reply *reply)
2124 {
2125 	unsigned short *tl = reply->tag_list;
2126 	union drbd_state s = mdev->state;
2127 	unsigned long rs_left;
2128 	unsigned int res;
2129 
2130 	tl = get_state_to_tags(mdev, (struct get_state *)&s, tl);
2131 
2132 	/* no local ref, no bitmap, no syncer progress. */
2133 	if (s.conn >= C_SYNC_SOURCE && s.conn <= C_PAUSED_SYNC_T) {
2134 		if (get_ldev(mdev)) {
2135 			drbd_get_syncer_progress(mdev, &rs_left, &res);
2136 			tl = tl_add_int(tl, T_sync_progress, &res);
2137 			put_ldev(mdev);
2138 		}
2139 	}
2140 	put_unaligned(TT_END, tl++); /* Close the tag list */
2141 
2142 	return (int)((char *)tl - (char *)reply->tag_list);
2143 }
2144 
2145 static int drbd_nl_get_uuids(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2146 			     struct drbd_nl_cfg_reply *reply)
2147 {
2148 	unsigned short *tl;
2149 
2150 	tl = reply->tag_list;
2151 
2152 	if (get_ldev(mdev)) {
2153 		tl = tl_add_blob(tl, T_uuids, mdev->ldev->md.uuid, UI_SIZE*sizeof(u64));
2154 		tl = tl_add_int(tl, T_uuids_flags, &mdev->ldev->md.flags);
2155 		put_ldev(mdev);
2156 	}
2157 	put_unaligned(TT_END, tl++); /* Close the tag list */
2158 
2159 	return (int)((char *)tl - (char *)reply->tag_list);
2160 }
2161 
2162 /**
2163  * drbd_nl_get_timeout_flag() - Used by drbdsetup to find out which timeout value to use
2164  * @mdev:	DRBD device.
2165  * @nlp:	Netlink/connector packet from drbdsetup
2166  * @reply:	Reply packet for drbdsetup
2167  */
2168 static int drbd_nl_get_timeout_flag(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2169 				    struct drbd_nl_cfg_reply *reply)
2170 {
2171 	unsigned short *tl;
2172 	char rv;
2173 
2174 	tl = reply->tag_list;
2175 
2176 	rv = mdev->state.pdsk == D_OUTDATED        ? UT_PEER_OUTDATED :
2177 	  test_bit(USE_DEGR_WFC_T, &mdev->flags) ? UT_DEGRADED : UT_DEFAULT;
2178 
2179 	tl = tl_add_blob(tl, T_use_degraded, &rv, sizeof(rv));
2180 	put_unaligned(TT_END, tl++); /* Close the tag list */
2181 
2182 	return (int)((char *)tl - (char *)reply->tag_list);
2183 }
2184 
2185 static int drbd_nl_start_ov(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2186 				    struct drbd_nl_cfg_reply *reply)
2187 {
2188 	/* default to resume from last known position, if possible */
2189 	struct start_ov args =
2190 		{ .start_sector = mdev->ov_start_sector };
2191 
2192 	if (!start_ov_from_tags(mdev, nlp->tag_list, &args)) {
2193 		reply->ret_code = ERR_MANDATORY_TAG;
2194 		return 0;
2195 	}
2196 
2197 	/* If there is still bitmap IO pending, e.g. previous resync or verify
2198 	 * just being finished, wait for it before requesting a new resync. */
2199 	drbd_suspend_io(mdev);
2200 	wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
2201 
2202 	/* w_make_ov_request expects position to be aligned */
2203 	mdev->ov_start_sector = args.start_sector & ~BM_SECT_PER_BIT;
2204 	reply->ret_code = drbd_request_state(mdev,NS(conn,C_VERIFY_S));
2205 	drbd_resume_io(mdev);
2206 	return 0;
2207 }
2208 
2209 
2210 static int drbd_nl_new_c_uuid(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2211 			      struct drbd_nl_cfg_reply *reply)
2212 {
2213 	int retcode = NO_ERROR;
2214 	int skip_initial_sync = 0;
2215 	int err;
2216 
2217 	struct new_c_uuid args;
2218 
2219 	memset(&args, 0, sizeof(struct new_c_uuid));
2220 	if (!new_c_uuid_from_tags(mdev, nlp->tag_list, &args)) {
2221 		reply->ret_code = ERR_MANDATORY_TAG;
2222 		return 0;
2223 	}
2224 
2225 	mutex_lock(&mdev->state_mutex); /* Protects us against serialized state changes. */
2226 
2227 	if (!get_ldev(mdev)) {
2228 		retcode = ERR_NO_DISK;
2229 		goto out;
2230 	}
2231 
2232 	/* this is "skip initial sync", assume to be clean */
2233 	if (mdev->state.conn == C_CONNECTED && mdev->agreed_pro_version >= 90 &&
2234 	    mdev->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED && args.clear_bm) {
2235 		dev_info(DEV, "Preparing to skip initial sync\n");
2236 		skip_initial_sync = 1;
2237 	} else if (mdev->state.conn != C_STANDALONE) {
2238 		retcode = ERR_CONNECTED;
2239 		goto out_dec;
2240 	}
2241 
2242 	drbd_uuid_set(mdev, UI_BITMAP, 0); /* Rotate UI_BITMAP to History 1, etc... */
2243 	drbd_uuid_new_current(mdev); /* New current, previous to UI_BITMAP */
2244 
2245 	if (args.clear_bm) {
2246 		err = drbd_bitmap_io(mdev, &drbd_bmio_clear_n_write,
2247 			"clear_n_write from new_c_uuid", BM_LOCKED_MASK);
2248 		if (err) {
2249 			dev_err(DEV, "Writing bitmap failed with %d\n",err);
2250 			retcode = ERR_IO_MD_DISK;
2251 		}
2252 		if (skip_initial_sync) {
2253 			drbd_send_uuids_skip_initial_sync(mdev);
2254 			_drbd_uuid_set(mdev, UI_BITMAP, 0);
2255 			drbd_print_uuids(mdev, "cleared bitmap UUID");
2256 			spin_lock_irq(&mdev->req_lock);
2257 			_drbd_set_state(_NS2(mdev, disk, D_UP_TO_DATE, pdsk, D_UP_TO_DATE),
2258 					CS_VERBOSE, NULL);
2259 			spin_unlock_irq(&mdev->req_lock);
2260 		}
2261 	}
2262 
2263 	drbd_md_sync(mdev);
2264 out_dec:
2265 	put_ldev(mdev);
2266 out:
2267 	mutex_unlock(&mdev->state_mutex);
2268 
2269 	reply->ret_code = retcode;
2270 	return 0;
2271 }
2272 
2273 struct cn_handler_struct {
2274 	int (*function)(struct drbd_conf *,
2275 			 struct drbd_nl_cfg_req *,
2276 			 struct drbd_nl_cfg_reply *);
2277 	int reply_body_size;
2278 };
2279 
2280 static struct cn_handler_struct cnd_table[] = {
2281 	[ P_primary ]		= { &drbd_nl_primary,		0 },
2282 	[ P_secondary ]		= { &drbd_nl_secondary,		0 },
2283 	[ P_disk_conf ]		= { &drbd_nl_disk_conf,		0 },
2284 	[ P_detach ]		= { &drbd_nl_detach,		0 },
2285 	[ P_net_conf ]		= { &drbd_nl_net_conf,		0 },
2286 	[ P_disconnect ]	= { &drbd_nl_disconnect,	0 },
2287 	[ P_resize ]		= { &drbd_nl_resize,		0 },
2288 	[ P_syncer_conf ]	= { &drbd_nl_syncer_conf,	0 },
2289 	[ P_invalidate ]	= { &drbd_nl_invalidate,	0 },
2290 	[ P_invalidate_peer ]	= { &drbd_nl_invalidate_peer,	0 },
2291 	[ P_pause_sync ]	= { &drbd_nl_pause_sync,	0 },
2292 	[ P_resume_sync ]	= { &drbd_nl_resume_sync,	0 },
2293 	[ P_suspend_io ]	= { &drbd_nl_suspend_io,	0 },
2294 	[ P_resume_io ]		= { &drbd_nl_resume_io,		0 },
2295 	[ P_outdate ]		= { &drbd_nl_outdate,		0 },
2296 	[ P_get_config ]	= { &drbd_nl_get_config,
2297 				    sizeof(struct syncer_conf_tag_len_struct) +
2298 				    sizeof(struct disk_conf_tag_len_struct) +
2299 				    sizeof(struct net_conf_tag_len_struct) },
2300 	[ P_get_state ]		= { &drbd_nl_get_state,
2301 				    sizeof(struct get_state_tag_len_struct) +
2302 				    sizeof(struct sync_progress_tag_len_struct)	},
2303 	[ P_get_uuids ]		= { &drbd_nl_get_uuids,
2304 				    sizeof(struct get_uuids_tag_len_struct) },
2305 	[ P_get_timeout_flag ]	= { &drbd_nl_get_timeout_flag,
2306 				    sizeof(struct get_timeout_flag_tag_len_struct)},
2307 	[ P_start_ov ]		= { &drbd_nl_start_ov,		0 },
2308 	[ P_new_c_uuid ]	= { &drbd_nl_new_c_uuid,	0 },
2309 };
2310 
2311 static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms *nsp)
2312 {
2313 	struct drbd_nl_cfg_req *nlp = (struct drbd_nl_cfg_req *)req->data;
2314 	struct cn_handler_struct *cm;
2315 	struct cn_msg *cn_reply;
2316 	struct drbd_nl_cfg_reply *reply;
2317 	struct drbd_conf *mdev;
2318 	int retcode, rr;
2319 	int reply_size = sizeof(struct cn_msg)
2320 		+ sizeof(struct drbd_nl_cfg_reply)
2321 		+ sizeof(short int);
2322 
2323 	if (!try_module_get(THIS_MODULE)) {
2324 		printk(KERN_ERR "drbd: try_module_get() failed!\n");
2325 		return;
2326 	}
2327 
2328 	if (!capable(CAP_SYS_ADMIN)) {
2329 		retcode = ERR_PERM;
2330 		goto fail;
2331 	}
2332 
2333 	mdev = ensure_mdev(nlp->drbd_minor,
2334 			(nlp->flags & DRBD_NL_CREATE_DEVICE));
2335 	if (!mdev) {
2336 		retcode = ERR_MINOR_INVALID;
2337 		goto fail;
2338 	}
2339 
2340 	if (nlp->packet_type >= P_nl_after_last_packet ||
2341 	    nlp->packet_type == P_return_code_only) {
2342 		retcode = ERR_PACKET_NR;
2343 		goto fail;
2344 	}
2345 
2346 	cm = cnd_table + nlp->packet_type;
2347 
2348 	/* This may happen if packet number is 0: */
2349 	if (cm->function == NULL) {
2350 		retcode = ERR_PACKET_NR;
2351 		goto fail;
2352 	}
2353 
2354 	reply_size += cm->reply_body_size;
2355 
2356 	/* allocation not in the IO path, cqueue thread context */
2357 	cn_reply = kzalloc(reply_size, GFP_KERNEL);
2358 	if (!cn_reply) {
2359 		retcode = ERR_NOMEM;
2360 		goto fail;
2361 	}
2362 	reply = (struct drbd_nl_cfg_reply *) cn_reply->data;
2363 
2364 	reply->packet_type =
2365 		cm->reply_body_size ? nlp->packet_type : P_return_code_only;
2366 	reply->minor = nlp->drbd_minor;
2367 	reply->ret_code = NO_ERROR; /* Might by modified by cm->function. */
2368 	/* reply->tag_list; might be modified by cm->function. */
2369 
2370 	rr = cm->function(mdev, nlp, reply);
2371 
2372 	cn_reply->id = req->id;
2373 	cn_reply->seq = req->seq;
2374 	cn_reply->ack = req->ack  + 1;
2375 	cn_reply->len = sizeof(struct drbd_nl_cfg_reply) + rr;
2376 	cn_reply->flags = 0;
2377 
2378 	rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_KERNEL);
2379 	if (rr && rr != -ESRCH)
2380 		printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2381 
2382 	kfree(cn_reply);
2383 	module_put(THIS_MODULE);
2384 	return;
2385  fail:
2386 	drbd_nl_send_reply(req, retcode);
2387 	module_put(THIS_MODULE);
2388 }
2389 
2390 static atomic_t drbd_nl_seq = ATOMIC_INIT(2); /* two. */
2391 
2392 static unsigned short *
2393 __tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data,
2394 	unsigned short len, int nul_terminated)
2395 {
2396 	unsigned short l = tag_descriptions[tag_number(tag)].max_len;
2397 	len = (len < l) ? len :  l;
2398 	put_unaligned(tag, tl++);
2399 	put_unaligned(len, tl++);
2400 	memcpy(tl, data, len);
2401 	tl = (unsigned short*)((char*)tl + len);
2402 	if (nul_terminated)
2403 		*((char*)tl - 1) = 0;
2404 	return tl;
2405 }
2406 
2407 static unsigned short *
2408 tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data, int len)
2409 {
2410 	return __tl_add_blob(tl, tag, data, len, 0);
2411 }
2412 
2413 static unsigned short *
2414 tl_add_str(unsigned short *tl, enum drbd_tags tag, const char *str)
2415 {
2416 	return __tl_add_blob(tl, tag, str, strlen(str)+1, 0);
2417 }
2418 
2419 static unsigned short *
2420 tl_add_int(unsigned short *tl, enum drbd_tags tag, const void *val)
2421 {
2422 	put_unaligned(tag, tl++);
2423 	switch(tag_type(tag)) {
2424 	case TT_INTEGER:
2425 		put_unaligned(sizeof(int), tl++);
2426 		put_unaligned(*(int *)val, (int *)tl);
2427 		tl = (unsigned short*)((char*)tl+sizeof(int));
2428 		break;
2429 	case TT_INT64:
2430 		put_unaligned(sizeof(u64), tl++);
2431 		put_unaligned(*(u64 *)val, (u64 *)tl);
2432 		tl = (unsigned short*)((char*)tl+sizeof(u64));
2433 		break;
2434 	default:
2435 		/* someone did something stupid. */
2436 		;
2437 	}
2438 	return tl;
2439 }
2440 
2441 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state state)
2442 {
2443 	char buffer[sizeof(struct cn_msg)+
2444 		    sizeof(struct drbd_nl_cfg_reply)+
2445 		    sizeof(struct get_state_tag_len_struct)+
2446 		    sizeof(short int)];
2447 	struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2448 	struct drbd_nl_cfg_reply *reply =
2449 		(struct drbd_nl_cfg_reply *)cn_reply->data;
2450 	unsigned short *tl = reply->tag_list;
2451 
2452 	/* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2453 
2454 	tl = get_state_to_tags(mdev, (struct get_state *)&state, tl);
2455 
2456 	put_unaligned(TT_END, tl++); /* Close the tag list */
2457 
2458 	cn_reply->id.idx = CN_IDX_DRBD;
2459 	cn_reply->id.val = CN_VAL_DRBD;
2460 
2461 	cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2462 	cn_reply->ack = 0; /* not used here. */
2463 	cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2464 		(int)((char *)tl - (char *)reply->tag_list);
2465 	cn_reply->flags = 0;
2466 
2467 	reply->packet_type = P_get_state;
2468 	reply->minor = mdev_to_minor(mdev);
2469 	reply->ret_code = NO_ERROR;
2470 
2471 	cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2472 }
2473 
2474 void drbd_bcast_ev_helper(struct drbd_conf *mdev, char *helper_name)
2475 {
2476 	char buffer[sizeof(struct cn_msg)+
2477 		    sizeof(struct drbd_nl_cfg_reply)+
2478 		    sizeof(struct call_helper_tag_len_struct)+
2479 		    sizeof(short int)];
2480 	struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2481 	struct drbd_nl_cfg_reply *reply =
2482 		(struct drbd_nl_cfg_reply *)cn_reply->data;
2483 	unsigned short *tl = reply->tag_list;
2484 
2485 	/* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2486 
2487 	tl = tl_add_str(tl, T_helper, helper_name);
2488 	put_unaligned(TT_END, tl++); /* Close the tag list */
2489 
2490 	cn_reply->id.idx = CN_IDX_DRBD;
2491 	cn_reply->id.val = CN_VAL_DRBD;
2492 
2493 	cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2494 	cn_reply->ack = 0; /* not used here. */
2495 	cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2496 		(int)((char *)tl - (char *)reply->tag_list);
2497 	cn_reply->flags = 0;
2498 
2499 	reply->packet_type = P_call_helper;
2500 	reply->minor = mdev_to_minor(mdev);
2501 	reply->ret_code = NO_ERROR;
2502 
2503 	cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2504 }
2505 
2506 void drbd_bcast_ee(struct drbd_conf *mdev,
2507 		const char *reason, const int dgs,
2508 		const char* seen_hash, const char* calc_hash,
2509 		const struct drbd_epoch_entry* e)
2510 {
2511 	struct cn_msg *cn_reply;
2512 	struct drbd_nl_cfg_reply *reply;
2513 	unsigned short *tl;
2514 	struct page *page;
2515 	unsigned len;
2516 
2517 	if (!e)
2518 		return;
2519 	if (!reason || !reason[0])
2520 		return;
2521 
2522 	/* apparently we have to memcpy twice, first to prepare the data for the
2523 	 * struct cn_msg, then within cn_netlink_send from the cn_msg to the
2524 	 * netlink skb. */
2525 	/* receiver thread context, which is not in the writeout path (of this node),
2526 	 * but may be in the writeout path of the _other_ node.
2527 	 * GFP_NOIO to avoid potential "distributed deadlock". */
2528 	cn_reply = kzalloc(
2529 		sizeof(struct cn_msg)+
2530 		sizeof(struct drbd_nl_cfg_reply)+
2531 		sizeof(struct dump_ee_tag_len_struct)+
2532 		sizeof(short int),
2533 		GFP_NOIO);
2534 
2535 	if (!cn_reply) {
2536 		dev_err(DEV, "could not kmalloc buffer for drbd_bcast_ee, sector %llu, size %u\n",
2537 				(unsigned long long)e->sector, e->size);
2538 		return;
2539 	}
2540 
2541 	reply = (struct drbd_nl_cfg_reply*)cn_reply->data;
2542 	tl = reply->tag_list;
2543 
2544 	tl = tl_add_str(tl, T_dump_ee_reason, reason);
2545 	tl = tl_add_blob(tl, T_seen_digest, seen_hash, dgs);
2546 	tl = tl_add_blob(tl, T_calc_digest, calc_hash, dgs);
2547 	tl = tl_add_int(tl, T_ee_sector, &e->sector);
2548 	tl = tl_add_int(tl, T_ee_block_id, &e->block_id);
2549 
2550 	/* dump the first 32k */
2551 	len = min_t(unsigned, e->size, 32 << 10);
2552 	put_unaligned(T_ee_data, tl++);
2553 	put_unaligned(len, tl++);
2554 
2555 	page = e->pages;
2556 	page_chain_for_each(page) {
2557 		void *d = kmap_atomic(page);
2558 		unsigned l = min_t(unsigned, len, PAGE_SIZE);
2559 		memcpy(tl, d, l);
2560 		kunmap_atomic(d);
2561 		tl = (unsigned short*)((char*)tl + l);
2562 		len -= l;
2563 		if (len == 0)
2564 			break;
2565 	}
2566 	put_unaligned(TT_END, tl++); /* Close the tag list */
2567 
2568 	cn_reply->id.idx = CN_IDX_DRBD;
2569 	cn_reply->id.val = CN_VAL_DRBD;
2570 
2571 	cn_reply->seq = atomic_add_return(1,&drbd_nl_seq);
2572 	cn_reply->ack = 0; // not used here.
2573 	cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2574 		(int)((char*)tl - (char*)reply->tag_list);
2575 	cn_reply->flags = 0;
2576 
2577 	reply->packet_type = P_dump_ee;
2578 	reply->minor = mdev_to_minor(mdev);
2579 	reply->ret_code = NO_ERROR;
2580 
2581 	cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2582 	kfree(cn_reply);
2583 }
2584 
2585 void drbd_bcast_sync_progress(struct drbd_conf *mdev)
2586 {
2587 	char buffer[sizeof(struct cn_msg)+
2588 		    sizeof(struct drbd_nl_cfg_reply)+
2589 		    sizeof(struct sync_progress_tag_len_struct)+
2590 		    sizeof(short int)];
2591 	struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2592 	struct drbd_nl_cfg_reply *reply =
2593 		(struct drbd_nl_cfg_reply *)cn_reply->data;
2594 	unsigned short *tl = reply->tag_list;
2595 	unsigned long rs_left;
2596 	unsigned int res;
2597 
2598 	/* no local ref, no bitmap, no syncer progress, no broadcast. */
2599 	if (!get_ldev(mdev))
2600 		return;
2601 	drbd_get_syncer_progress(mdev, &rs_left, &res);
2602 	put_ldev(mdev);
2603 
2604 	tl = tl_add_int(tl, T_sync_progress, &res);
2605 	put_unaligned(TT_END, tl++); /* Close the tag list */
2606 
2607 	cn_reply->id.idx = CN_IDX_DRBD;
2608 	cn_reply->id.val = CN_VAL_DRBD;
2609 
2610 	cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2611 	cn_reply->ack = 0; /* not used here. */
2612 	cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2613 		(int)((char *)tl - (char *)reply->tag_list);
2614 	cn_reply->flags = 0;
2615 
2616 	reply->packet_type = P_sync_progress;
2617 	reply->minor = mdev_to_minor(mdev);
2618 	reply->ret_code = NO_ERROR;
2619 
2620 	cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2621 }
2622 
2623 int __init drbd_nl_init(void)
2624 {
2625 	static struct cb_id cn_id_drbd;
2626 	int err, try=10;
2627 
2628 	cn_id_drbd.val = CN_VAL_DRBD;
2629 	do {
2630 		cn_id_drbd.idx = cn_idx;
2631 		err = cn_add_callback(&cn_id_drbd, "cn_drbd", &drbd_connector_callback);
2632 		if (!err)
2633 			break;
2634 		cn_idx = (cn_idx + CN_IDX_STEP);
2635 	} while (try--);
2636 
2637 	if (err) {
2638 		printk(KERN_ERR "drbd: cn_drbd failed to register\n");
2639 		return err;
2640 	}
2641 
2642 	return 0;
2643 }
2644 
2645 void drbd_nl_cleanup(void)
2646 {
2647 	static struct cb_id cn_id_drbd;
2648 
2649 	cn_id_drbd.idx = cn_idx;
2650 	cn_id_drbd.val = CN_VAL_DRBD;
2651 
2652 	cn_del_callback(&cn_id_drbd);
2653 }
2654 
2655 void drbd_nl_send_reply(struct cn_msg *req, int ret_code)
2656 {
2657 	char buffer[sizeof(struct cn_msg)+sizeof(struct drbd_nl_cfg_reply)];
2658 	struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2659 	struct drbd_nl_cfg_reply *reply =
2660 		(struct drbd_nl_cfg_reply *)cn_reply->data;
2661 	int rr;
2662 
2663 	memset(buffer, 0, sizeof(buffer));
2664 	cn_reply->id = req->id;
2665 
2666 	cn_reply->seq = req->seq;
2667 	cn_reply->ack = req->ack  + 1;
2668 	cn_reply->len = sizeof(struct drbd_nl_cfg_reply);
2669 	cn_reply->flags = 0;
2670 
2671 	reply->packet_type = P_return_code_only;
2672 	reply->minor = ((struct drbd_nl_cfg_req *)req->data)->drbd_minor;
2673 	reply->ret_code = ret_code;
2674 
2675 	rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2676 	if (rr && rr != -ESRCH)
2677 		printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2678 }
2679 
2680