fs: fix superblock iteration race
[sfrench/cifs-2.6.git] / drivers / block / drbd / drbd_nl.c
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_wrappers.h"
37 #include <asm/unaligned.h>
38 #include <linux/drbd_tag_magic.h>
39 #include <linux/drbd_limits.h>
40
41 static unsigned short *tl_add_blob(unsigned short *, enum drbd_tags, const void *, int);
42 static unsigned short *tl_add_str(unsigned short *, enum drbd_tags, const char *);
43 static unsigned short *tl_add_int(unsigned short *, enum drbd_tags, const void *);
44
45 /* see get_sb_bdev and bd_claim */
46 static char *drbd_m_holder = "Hands off! this is DRBD's meta data device.";
47
48 /* Generate the tag_list to struct functions */
49 #define NL_PACKET(name, number, fields) \
50 static int name ## _from_tags(struct drbd_conf *mdev, \
51         unsigned short *tags, struct name *arg) __attribute__ ((unused)); \
52 static int name ## _from_tags(struct drbd_conf *mdev, \
53         unsigned short *tags, struct name *arg) \
54 { \
55         int tag; \
56         int dlen; \
57         \
58         while ((tag = get_unaligned(tags++)) != TT_END) {       \
59                 dlen = get_unaligned(tags++);                   \
60                 switch (tag_number(tag)) { \
61                 fields \
62                 default: \
63                         if (tag & T_MANDATORY) { \
64                                 dev_err(DEV, "Unknown tag: %d\n", tag_number(tag)); \
65                                 return 0; \
66                         } \
67                 } \
68                 tags = (unsigned short *)((char *)tags + dlen); \
69         } \
70         return 1; \
71 }
72 #define NL_INTEGER(pn, pr, member) \
73         case pn: /* D_ASSERT( tag_type(tag) == TT_INTEGER ); */ \
74                 arg->member = get_unaligned((int *)(tags));     \
75                 break;
76 #define NL_INT64(pn, pr, member) \
77         case pn: /* D_ASSERT( tag_type(tag) == TT_INT64 ); */ \
78                 arg->member = get_unaligned((u64 *)(tags));     \
79                 break;
80 #define NL_BIT(pn, pr, member) \
81         case pn: /* D_ASSERT( tag_type(tag) == TT_BIT ); */ \
82                 arg->member = *(char *)(tags) ? 1 : 0; \
83                 break;
84 #define NL_STRING(pn, pr, member, len) \
85         case pn: /* D_ASSERT( tag_type(tag) == TT_STRING ); */ \
86                 if (dlen > len) { \
87                         dev_err(DEV, "arg too long: %s (%u wanted, max len: %u bytes)\n", \
88                                 #member, dlen, (unsigned int)len); \
89                         return 0; \
90                 } \
91                  arg->member ## _len = dlen; \
92                  memcpy(arg->member, tags, min_t(size_t, dlen, len)); \
93                  break;
94 #include "linux/drbd_nl.h"
95
96 /* Generate the struct to tag_list functions */
97 #define NL_PACKET(name, number, fields) \
98 static unsigned short* \
99 name ## _to_tags(struct drbd_conf *mdev, \
100         struct name *arg, unsigned short *tags) __attribute__ ((unused)); \
101 static unsigned short* \
102 name ## _to_tags(struct drbd_conf *mdev, \
103         struct name *arg, unsigned short *tags) \
104 { \
105         fields \
106         return tags; \
107 }
108
109 #define NL_INTEGER(pn, pr, member) \
110         put_unaligned(pn | pr | TT_INTEGER, tags++);    \
111         put_unaligned(sizeof(int), tags++);             \
112         put_unaligned(arg->member, (int *)tags);        \
113         tags = (unsigned short *)((char *)tags+sizeof(int));
114 #define NL_INT64(pn, pr, member) \
115         put_unaligned(pn | pr | TT_INT64, tags++);      \
116         put_unaligned(sizeof(u64), tags++);             \
117         put_unaligned(arg->member, (u64 *)tags);        \
118         tags = (unsigned short *)((char *)tags+sizeof(u64));
119 #define NL_BIT(pn, pr, member) \
120         put_unaligned(pn | pr | TT_BIT, tags++);        \
121         put_unaligned(sizeof(char), tags++);            \
122         *(char *)tags = arg->member; \
123         tags = (unsigned short *)((char *)tags+sizeof(char));
124 #define NL_STRING(pn, pr, member, len) \
125         put_unaligned(pn | pr | TT_STRING, tags++);     \
126         put_unaligned(arg->member ## _len, tags++);     \
127         memcpy(tags, arg->member, arg->member ## _len); \
128         tags = (unsigned short *)((char *)tags + arg->member ## _len);
129 #include "linux/drbd_nl.h"
130
131 void drbd_bcast_ev_helper(struct drbd_conf *mdev, char *helper_name);
132 void drbd_nl_send_reply(struct cn_msg *, int);
133
134 int drbd_khelper(struct drbd_conf *mdev, char *cmd)
135 {
136         char *envp[] = { "HOME=/",
137                         "TERM=linux",
138                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
139                         NULL, /* Will be set to address family */
140                         NULL, /* Will be set to address */
141                         NULL };
142
143         char mb[12], af[20], ad[60], *afs;
144         char *argv[] = {usermode_helper, cmd, mb, NULL };
145         int ret;
146
147         snprintf(mb, 12, "minor-%d", mdev_to_minor(mdev));
148
149         if (get_net_conf(mdev)) {
150                 switch (((struct sockaddr *)mdev->net_conf->peer_addr)->sa_family) {
151                 case AF_INET6:
152                         afs = "ipv6";
153                         snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI6",
154                                  &((struct sockaddr_in6 *)mdev->net_conf->peer_addr)->sin6_addr);
155                         break;
156                 case AF_INET:
157                         afs = "ipv4";
158                         snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI4",
159                                  &((struct sockaddr_in *)mdev->net_conf->peer_addr)->sin_addr);
160                         break;
161                 default:
162                         afs = "ssocks";
163                         snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI4",
164                                  &((struct sockaddr_in *)mdev->net_conf->peer_addr)->sin_addr);
165                 }
166                 snprintf(af, 20, "DRBD_PEER_AF=%s", afs);
167                 envp[3]=af;
168                 envp[4]=ad;
169                 put_net_conf(mdev);
170         }
171
172         dev_info(DEV, "helper command: %s %s %s\n", usermode_helper, cmd, mb);
173
174         drbd_bcast_ev_helper(mdev, cmd);
175         ret = call_usermodehelper(usermode_helper, argv, envp, 1);
176         if (ret)
177                 dev_warn(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
178                                 usermode_helper, cmd, mb,
179                                 (ret >> 8) & 0xff, ret);
180         else
181                 dev_info(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
182                                 usermode_helper, cmd, mb,
183                                 (ret >> 8) & 0xff, ret);
184
185         if (ret < 0) /* Ignore any ERRNOs we got. */
186                 ret = 0;
187
188         return ret;
189 }
190
191 enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev)
192 {
193         char *ex_to_string;
194         int r;
195         enum drbd_disk_state nps;
196         enum drbd_fencing_p fp;
197
198         D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
199
200         if (get_ldev_if_state(mdev, D_CONSISTENT)) {
201                 fp = mdev->ldev->dc.fencing;
202                 put_ldev(mdev);
203         } else {
204                 dev_warn(DEV, "Not fencing peer, I'm not even Consistent myself.\n");
205                 return mdev->state.pdsk;
206         }
207
208         if (fp == FP_STONITH)
209                 _drbd_request_state(mdev, NS(susp, 1), CS_WAIT_COMPLETE);
210
211         r = drbd_khelper(mdev, "fence-peer");
212
213         switch ((r>>8) & 0xff) {
214         case 3: /* peer is inconsistent */
215                 ex_to_string = "peer is inconsistent or worse";
216                 nps = D_INCONSISTENT;
217                 break;
218         case 4: /* peer got outdated, or was already outdated */
219                 ex_to_string = "peer was fenced";
220                 nps = D_OUTDATED;
221                 break;
222         case 5: /* peer was down */
223                 if (mdev->state.disk == D_UP_TO_DATE) {
224                         /* we will(have) create(d) a new UUID anyways... */
225                         ex_to_string = "peer is unreachable, assumed to be dead";
226                         nps = D_OUTDATED;
227                 } else {
228                         ex_to_string = "peer unreachable, doing nothing since disk != UpToDate";
229                         nps = mdev->state.pdsk;
230                 }
231                 break;
232         case 6: /* Peer is primary, voluntarily outdate myself.
233                  * This is useful when an unconnected R_SECONDARY is asked to
234                  * become R_PRIMARY, but finds the other peer being active. */
235                 ex_to_string = "peer is active";
236                 dev_warn(DEV, "Peer is primary, outdating myself.\n");
237                 nps = D_UNKNOWN;
238                 _drbd_request_state(mdev, NS(disk, D_OUTDATED), CS_WAIT_COMPLETE);
239                 break;
240         case 7:
241                 if (fp != FP_STONITH)
242                         dev_err(DEV, "fence-peer() = 7 && fencing != Stonith !!!\n");
243                 ex_to_string = "peer was stonithed";
244                 nps = D_OUTDATED;
245                 break;
246         default:
247                 /* The script is broken ... */
248                 nps = D_UNKNOWN;
249                 dev_err(DEV, "fence-peer helper broken, returned %d\n", (r>>8)&0xff);
250                 return nps;
251         }
252
253         dev_info(DEV, "fence-peer helper returned %d (%s)\n",
254                         (r>>8) & 0xff, ex_to_string);
255         return nps;
256 }
257
258
259 int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, int force)
260 {
261         const int max_tries = 4;
262         int r = 0;
263         int try = 0;
264         int forced = 0;
265         union drbd_state mask, val;
266         enum drbd_disk_state nps;
267
268         if (new_role == R_PRIMARY)
269                 request_ping(mdev); /* Detect a dead peer ASAP */
270
271         mutex_lock(&mdev->state_mutex);
272
273         mask.i = 0; mask.role = R_MASK;
274         val.i  = 0; val.role  = new_role;
275
276         while (try++ < max_tries) {
277                 r = _drbd_request_state(mdev, mask, val, CS_WAIT_COMPLETE);
278
279                 /* in case we first succeeded to outdate,
280                  * but now suddenly could establish a connection */
281                 if (r == SS_CW_FAILED_BY_PEER && mask.pdsk != 0) {
282                         val.pdsk = 0;
283                         mask.pdsk = 0;
284                         continue;
285                 }
286
287                 if (r == SS_NO_UP_TO_DATE_DISK && force &&
288                     (mdev->state.disk < D_UP_TO_DATE &&
289                      mdev->state.disk >= D_INCONSISTENT)) {
290                         mask.disk = D_MASK;
291                         val.disk  = D_UP_TO_DATE;
292                         forced = 1;
293                         continue;
294                 }
295
296                 if (r == SS_NO_UP_TO_DATE_DISK &&
297                     mdev->state.disk == D_CONSISTENT && mask.pdsk == 0) {
298                         D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
299                         nps = drbd_try_outdate_peer(mdev);
300
301                         if (nps == D_OUTDATED || nps == D_INCONSISTENT) {
302                                 val.disk = D_UP_TO_DATE;
303                                 mask.disk = D_MASK;
304                         }
305
306                         val.pdsk = nps;
307                         mask.pdsk = D_MASK;
308
309                         continue;
310                 }
311
312                 if (r == SS_NOTHING_TO_DO)
313                         goto fail;
314                 if (r == SS_PRIMARY_NOP && mask.pdsk == 0) {
315                         nps = drbd_try_outdate_peer(mdev);
316
317                         if (force && nps > D_OUTDATED) {
318                                 dev_warn(DEV, "Forced into split brain situation!\n");
319                                 nps = D_OUTDATED;
320                         }
321
322                         mask.pdsk = D_MASK;
323                         val.pdsk  = nps;
324
325                         continue;
326                 }
327                 if (r == SS_TWO_PRIMARIES) {
328                         /* Maybe the peer is detected as dead very soon...
329                            retry at most once more in this case. */
330                         __set_current_state(TASK_INTERRUPTIBLE);
331                         schedule_timeout((mdev->net_conf->ping_timeo+1)*HZ/10);
332                         if (try < max_tries)
333                                 try = max_tries - 1;
334                         continue;
335                 }
336                 if (r < SS_SUCCESS) {
337                         r = _drbd_request_state(mdev, mask, val,
338                                                 CS_VERBOSE + CS_WAIT_COMPLETE);
339                         if (r < SS_SUCCESS)
340                                 goto fail;
341                 }
342                 break;
343         }
344
345         if (r < SS_SUCCESS)
346                 goto fail;
347
348         if (forced)
349                 dev_warn(DEV, "Forced to consider local data as UpToDate!\n");
350
351         /* Wait until nothing is on the fly :) */
352         wait_event(mdev->misc_wait, atomic_read(&mdev->ap_pending_cnt) == 0);
353
354         if (new_role == R_SECONDARY) {
355                 set_disk_ro(mdev->vdisk, TRUE);
356                 if (get_ldev(mdev)) {
357                         mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
358                         put_ldev(mdev);
359                 }
360         } else {
361                 if (get_net_conf(mdev)) {
362                         mdev->net_conf->want_lose = 0;
363                         put_net_conf(mdev);
364                 }
365                 set_disk_ro(mdev->vdisk, FALSE);
366                 if (get_ldev(mdev)) {
367                         if (((mdev->state.conn < C_CONNECTED ||
368                                mdev->state.pdsk <= D_FAILED)
369                               && mdev->ldev->md.uuid[UI_BITMAP] == 0) || forced)
370                                 drbd_uuid_new_current(mdev);
371
372                         mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
373                         put_ldev(mdev);
374                 }
375         }
376
377         if ((new_role == R_SECONDARY) && get_ldev(mdev)) {
378                 drbd_al_to_on_disk_bm(mdev);
379                 put_ldev(mdev);
380         }
381
382         if (mdev->state.conn >= C_WF_REPORT_PARAMS) {
383                 /* if this was forced, we should consider sync */
384                 if (forced)
385                         drbd_send_uuids(mdev);
386                 drbd_send_state(mdev);
387         }
388
389         drbd_md_sync(mdev);
390
391         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
392  fail:
393         mutex_unlock(&mdev->state_mutex);
394         return r;
395 }
396
397
398 static int drbd_nl_primary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
399                            struct drbd_nl_cfg_reply *reply)
400 {
401         struct primary primary_args;
402
403         memset(&primary_args, 0, sizeof(struct primary));
404         if (!primary_from_tags(mdev, nlp->tag_list, &primary_args)) {
405                 reply->ret_code = ERR_MANDATORY_TAG;
406                 return 0;
407         }
408
409         reply->ret_code =
410                 drbd_set_role(mdev, R_PRIMARY, primary_args.primary_force);
411
412         return 0;
413 }
414
415 static int drbd_nl_secondary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
416                              struct drbd_nl_cfg_reply *reply)
417 {
418         reply->ret_code = drbd_set_role(mdev, R_SECONDARY, 0);
419
420         return 0;
421 }
422
423 /* initializes the md.*_offset members, so we are able to find
424  * the on disk meta data */
425 static void drbd_md_set_sector_offsets(struct drbd_conf *mdev,
426                                        struct drbd_backing_dev *bdev)
427 {
428         sector_t md_size_sect = 0;
429         switch (bdev->dc.meta_dev_idx) {
430         default:
431                 /* v07 style fixed size indexed meta data */
432                 bdev->md.md_size_sect = MD_RESERVED_SECT;
433                 bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
434                 bdev->md.al_offset = MD_AL_OFFSET;
435                 bdev->md.bm_offset = MD_BM_OFFSET;
436                 break;
437         case DRBD_MD_INDEX_FLEX_EXT:
438                 /* just occupy the full device; unit: sectors */
439                 bdev->md.md_size_sect = drbd_get_capacity(bdev->md_bdev);
440                 bdev->md.md_offset = 0;
441                 bdev->md.al_offset = MD_AL_OFFSET;
442                 bdev->md.bm_offset = MD_BM_OFFSET;
443                 break;
444         case DRBD_MD_INDEX_INTERNAL:
445         case DRBD_MD_INDEX_FLEX_INT:
446                 bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
447                 /* al size is still fixed */
448                 bdev->md.al_offset = -MD_AL_MAX_SIZE;
449                 /* we need (slightly less than) ~ this much bitmap sectors: */
450                 md_size_sect = drbd_get_capacity(bdev->backing_bdev);
451                 md_size_sect = ALIGN(md_size_sect, BM_SECT_PER_EXT);
452                 md_size_sect = BM_SECT_TO_EXT(md_size_sect);
453                 md_size_sect = ALIGN(md_size_sect, 8);
454
455                 /* plus the "drbd meta data super block",
456                  * and the activity log; */
457                 md_size_sect += MD_BM_OFFSET;
458
459                 bdev->md.md_size_sect = md_size_sect;
460                 /* bitmap offset is adjusted by 'super' block size */
461                 bdev->md.bm_offset   = -md_size_sect + MD_AL_OFFSET;
462                 break;
463         }
464 }
465
466 char *ppsize(char *buf, unsigned long long size)
467 {
468         /* Needs 9 bytes at max. */
469         static char units[] = { 'K', 'M', 'G', 'T', 'P', 'E' };
470         int base = 0;
471         while (size >= 10000) {
472                 /* shift + round */
473                 size = (size >> 10) + !!(size & (1<<9));
474                 base++;
475         }
476         sprintf(buf, "%lu %cB", (long)size, units[base]);
477
478         return buf;
479 }
480
481 /* there is still a theoretical deadlock when called from receiver
482  * on an D_INCONSISTENT R_PRIMARY:
483  *  remote READ does inc_ap_bio, receiver would need to receive answer
484  *  packet from remote to dec_ap_bio again.
485  *  receiver receive_sizes(), comes here,
486  *  waits for ap_bio_cnt == 0. -> deadlock.
487  * but this cannot happen, actually, because:
488  *  R_PRIMARY D_INCONSISTENT, and peer's disk is unreachable
489  *  (not connected, or bad/no disk on peer):
490  *  see drbd_fail_request_early, ap_bio_cnt is zero.
491  *  R_PRIMARY D_INCONSISTENT, and C_SYNC_TARGET:
492  *  peer may not initiate a resize.
493  */
494 void drbd_suspend_io(struct drbd_conf *mdev)
495 {
496         set_bit(SUSPEND_IO, &mdev->flags);
497         wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
498 }
499
500 void drbd_resume_io(struct drbd_conf *mdev)
501 {
502         clear_bit(SUSPEND_IO, &mdev->flags);
503         wake_up(&mdev->misc_wait);
504 }
505
506 /**
507  * drbd_determine_dev_size() -  Sets the right device size obeying all constraints
508  * @mdev:       DRBD device.
509  *
510  * Returns 0 on success, negative return values indicate errors.
511  * You should call drbd_md_sync() after calling this function.
512  */
513 enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *mdev, enum dds_flags flags) __must_hold(local)
514 {
515         sector_t prev_first_sect, prev_size; /* previous meta location */
516         sector_t la_size;
517         sector_t size;
518         char ppb[10];
519
520         int md_moved, la_size_changed;
521         enum determine_dev_size rv = unchanged;
522
523         /* race:
524          * application request passes inc_ap_bio,
525          * but then cannot get an AL-reference.
526          * this function later may wait on ap_bio_cnt == 0. -> deadlock.
527          *
528          * to avoid that:
529          * Suspend IO right here.
530          * still lock the act_log to not trigger ASSERTs there.
531          */
532         drbd_suspend_io(mdev);
533
534         /* no wait necessary anymore, actually we could assert that */
535         wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
536
537         prev_first_sect = drbd_md_first_sector(mdev->ldev);
538         prev_size = mdev->ldev->md.md_size_sect;
539         la_size = mdev->ldev->md.la_size_sect;
540
541         /* TODO: should only be some assert here, not (re)init... */
542         drbd_md_set_sector_offsets(mdev, mdev->ldev);
543
544         size = drbd_new_dev_size(mdev, mdev->ldev, flags & DDSF_FORCED);
545
546         if (drbd_get_capacity(mdev->this_bdev) != size ||
547             drbd_bm_capacity(mdev) != size) {
548                 int err;
549                 err = drbd_bm_resize(mdev, size, !(flags & DDSF_NO_RESYNC));
550                 if (unlikely(err)) {
551                         /* currently there is only one error: ENOMEM! */
552                         size = drbd_bm_capacity(mdev)>>1;
553                         if (size == 0) {
554                                 dev_err(DEV, "OUT OF MEMORY! "
555                                     "Could not allocate bitmap!\n");
556                         } else {
557                                 dev_err(DEV, "BM resizing failed. "
558                                     "Leaving size unchanged at size = %lu KB\n",
559                                     (unsigned long)size);
560                         }
561                         rv = dev_size_error;
562                 }
563                 /* racy, see comments above. */
564                 drbd_set_my_capacity(mdev, size);
565                 mdev->ldev->md.la_size_sect = size;
566                 dev_info(DEV, "size = %s (%llu KB)\n", ppsize(ppb, size>>1),
567                      (unsigned long long)size>>1);
568         }
569         if (rv == dev_size_error)
570                 goto out;
571
572         la_size_changed = (la_size != mdev->ldev->md.la_size_sect);
573
574         md_moved = prev_first_sect != drbd_md_first_sector(mdev->ldev)
575                 || prev_size       != mdev->ldev->md.md_size_sect;
576
577         if (la_size_changed || md_moved) {
578                 drbd_al_shrink(mdev); /* All extents inactive. */
579                 dev_info(DEV, "Writing the whole bitmap, %s\n",
580                          la_size_changed && md_moved ? "size changed and md moved" :
581                          la_size_changed ? "size changed" : "md moved");
582                 rv = drbd_bitmap_io(mdev, &drbd_bm_write, "size changed"); /* does drbd_resume_io() ! */
583                 drbd_md_mark_dirty(mdev);
584         }
585
586         if (size > la_size)
587                 rv = grew;
588         if (size < la_size)
589                 rv = shrunk;
590 out:
591         lc_unlock(mdev->act_log);
592         wake_up(&mdev->al_wait);
593         drbd_resume_io(mdev);
594
595         return rv;
596 }
597
598 sector_t
599 drbd_new_dev_size(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, int assume_peer_has_space)
600 {
601         sector_t p_size = mdev->p_size;   /* partner's disk size. */
602         sector_t la_size = bdev->md.la_size_sect; /* last agreed size. */
603         sector_t m_size; /* my size */
604         sector_t u_size = bdev->dc.disk_size; /* size requested by user. */
605         sector_t size = 0;
606
607         m_size = drbd_get_max_capacity(bdev);
608
609         if (mdev->state.conn < C_CONNECTED && assume_peer_has_space) {
610                 dev_warn(DEV, "Resize while not connected was forced by the user!\n");
611                 p_size = m_size;
612         }
613
614         if (p_size && m_size) {
615                 size = min_t(sector_t, p_size, m_size);
616         } else {
617                 if (la_size) {
618                         size = la_size;
619                         if (m_size && m_size < size)
620                                 size = m_size;
621                         if (p_size && p_size < size)
622                                 size = p_size;
623                 } else {
624                         if (m_size)
625                                 size = m_size;
626                         if (p_size)
627                                 size = p_size;
628                 }
629         }
630
631         if (size == 0)
632                 dev_err(DEV, "Both nodes diskless!\n");
633
634         if (u_size) {
635                 if (u_size > size)
636                         dev_err(DEV, "Requested disk size is too big (%lu > %lu)\n",
637                             (unsigned long)u_size>>1, (unsigned long)size>>1);
638                 else
639                         size = u_size;
640         }
641
642         return size;
643 }
644
645 /**
646  * drbd_check_al_size() - Ensures that the AL is of the right size
647  * @mdev:       DRBD device.
648  *
649  * Returns -EBUSY if current al lru is still used, -ENOMEM when allocation
650  * failed, and 0 on success. You should call drbd_md_sync() after you called
651  * this function.
652  */
653 static int drbd_check_al_size(struct drbd_conf *mdev)
654 {
655         struct lru_cache *n, *t;
656         struct lc_element *e;
657         unsigned int in_use;
658         int i;
659
660         ERR_IF(mdev->sync_conf.al_extents < 7)
661                 mdev->sync_conf.al_extents = 127;
662
663         if (mdev->act_log &&
664             mdev->act_log->nr_elements == mdev->sync_conf.al_extents)
665                 return 0;
666
667         in_use = 0;
668         t = mdev->act_log;
669         n = lc_create("act_log", drbd_al_ext_cache,
670                 mdev->sync_conf.al_extents, sizeof(struct lc_element), 0);
671
672         if (n == NULL) {
673                 dev_err(DEV, "Cannot allocate act_log lru!\n");
674                 return -ENOMEM;
675         }
676         spin_lock_irq(&mdev->al_lock);
677         if (t) {
678                 for (i = 0; i < t->nr_elements; i++) {
679                         e = lc_element_by_index(t, i);
680                         if (e->refcnt)
681                                 dev_err(DEV, "refcnt(%d)==%d\n",
682                                     e->lc_number, e->refcnt);
683                         in_use += e->refcnt;
684                 }
685         }
686         if (!in_use)
687                 mdev->act_log = n;
688         spin_unlock_irq(&mdev->al_lock);
689         if (in_use) {
690                 dev_err(DEV, "Activity log still in use!\n");
691                 lc_destroy(n);
692                 return -EBUSY;
693         } else {
694                 if (t)
695                         lc_destroy(t);
696         }
697         drbd_md_mark_dirty(mdev); /* we changed mdev->act_log->nr_elemens */
698         return 0;
699 }
700
701 void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_seg_s) __must_hold(local)
702 {
703         struct request_queue * const q = mdev->rq_queue;
704         struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
705         int max_segments = mdev->ldev->dc.max_bio_bvecs;
706
707         max_seg_s = min(queue_max_sectors(b) * queue_logical_block_size(b), max_seg_s);
708
709         blk_queue_max_hw_sectors(q, max_seg_s >> 9);
710         blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
711         blk_queue_max_segment_size(q, max_seg_s);
712         blk_queue_logical_block_size(q, 512);
713         blk_queue_segment_boundary(q, PAGE_SIZE-1);
714         blk_stack_limits(&q->limits, &b->limits, 0);
715
716         if (b->merge_bvec_fn)
717                 dev_warn(DEV, "Backing device's merge_bvec_fn() = %p\n",
718                      b->merge_bvec_fn);
719         dev_info(DEV, "max_segment_size ( = BIO size ) = %u\n", queue_max_segment_size(q));
720
721         if (q->backing_dev_info.ra_pages != b->backing_dev_info.ra_pages) {
722                 dev_info(DEV, "Adjusting my ra_pages to backing device's (%lu -> %lu)\n",
723                      q->backing_dev_info.ra_pages,
724                      b->backing_dev_info.ra_pages);
725                 q->backing_dev_info.ra_pages = b->backing_dev_info.ra_pages;
726         }
727 }
728
729 /* serialize deconfig (worker exiting, doing cleanup)
730  * and reconfig (drbdsetup disk, drbdsetup net)
731  *
732  * wait for a potentially exiting worker, then restart it,
733  * or start a new one.
734  */
735 static void drbd_reconfig_start(struct drbd_conf *mdev)
736 {
737         wait_event(mdev->state_wait, !test_and_set_bit(CONFIG_PENDING, &mdev->flags));
738         wait_event(mdev->state_wait, !test_bit(DEVICE_DYING, &mdev->flags));
739         drbd_thread_start(&mdev->worker);
740 }
741
742 /* if still unconfigured, stops worker again.
743  * if configured now, clears CONFIG_PENDING.
744  * wakes potential waiters */
745 static void drbd_reconfig_done(struct drbd_conf *mdev)
746 {
747         spin_lock_irq(&mdev->req_lock);
748         if (mdev->state.disk == D_DISKLESS &&
749             mdev->state.conn == C_STANDALONE &&
750             mdev->state.role == R_SECONDARY) {
751                 set_bit(DEVICE_DYING, &mdev->flags);
752                 drbd_thread_stop_nowait(&mdev->worker);
753         } else
754                 clear_bit(CONFIG_PENDING, &mdev->flags);
755         spin_unlock_irq(&mdev->req_lock);
756         wake_up(&mdev->state_wait);
757 }
758
759 /* does always return 0;
760  * interesting return code is in reply->ret_code */
761 static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
762                              struct drbd_nl_cfg_reply *reply)
763 {
764         enum drbd_ret_codes retcode;
765         enum determine_dev_size dd;
766         sector_t max_possible_sectors;
767         sector_t min_md_device_sectors;
768         struct drbd_backing_dev *nbc = NULL; /* new_backing_conf */
769         struct inode *inode, *inode2;
770         struct lru_cache *resync_lru = NULL;
771         union drbd_state ns, os;
772         int rv;
773         int cp_discovered = 0;
774         int logical_block_size;
775
776         drbd_reconfig_start(mdev);
777
778         /* if you want to reconfigure, please tear down first */
779         if (mdev->state.disk > D_DISKLESS) {
780                 retcode = ERR_DISK_CONFIGURED;
781                 goto fail;
782         }
783
784         /* allocation not in the IO path, cqueue thread context */
785         nbc = kzalloc(sizeof(struct drbd_backing_dev), GFP_KERNEL);
786         if (!nbc) {
787                 retcode = ERR_NOMEM;
788                 goto fail;
789         }
790
791         nbc->dc.disk_size     = DRBD_DISK_SIZE_SECT_DEF;
792         nbc->dc.on_io_error   = DRBD_ON_IO_ERROR_DEF;
793         nbc->dc.fencing       = DRBD_FENCING_DEF;
794         nbc->dc.max_bio_bvecs = DRBD_MAX_BIO_BVECS_DEF;
795
796         if (!disk_conf_from_tags(mdev, nlp->tag_list, &nbc->dc)) {
797                 retcode = ERR_MANDATORY_TAG;
798                 goto fail;
799         }
800
801         if (nbc->dc.meta_dev_idx < DRBD_MD_INDEX_FLEX_INT) {
802                 retcode = ERR_MD_IDX_INVALID;
803                 goto fail;
804         }
805
806         nbc->lo_file = filp_open(nbc->dc.backing_dev, O_RDWR, 0);
807         if (IS_ERR(nbc->lo_file)) {
808                 dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.backing_dev,
809                     PTR_ERR(nbc->lo_file));
810                 nbc->lo_file = NULL;
811                 retcode = ERR_OPEN_DISK;
812                 goto fail;
813         }
814
815         inode = nbc->lo_file->f_dentry->d_inode;
816
817         if (!S_ISBLK(inode->i_mode)) {
818                 retcode = ERR_DISK_NOT_BDEV;
819                 goto fail;
820         }
821
822         nbc->md_file = filp_open(nbc->dc.meta_dev, O_RDWR, 0);
823         if (IS_ERR(nbc->md_file)) {
824                 dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.meta_dev,
825                     PTR_ERR(nbc->md_file));
826                 nbc->md_file = NULL;
827                 retcode = ERR_OPEN_MD_DISK;
828                 goto fail;
829         }
830
831         inode2 = nbc->md_file->f_dentry->d_inode;
832
833         if (!S_ISBLK(inode2->i_mode)) {
834                 retcode = ERR_MD_NOT_BDEV;
835                 goto fail;
836         }
837
838         nbc->backing_bdev = inode->i_bdev;
839         if (bd_claim(nbc->backing_bdev, mdev)) {
840                 printk(KERN_ERR "drbd: bd_claim(%p,%p); failed [%p;%p;%u]\n",
841                        nbc->backing_bdev, mdev,
842                        nbc->backing_bdev->bd_holder,
843                        nbc->backing_bdev->bd_contains->bd_holder,
844                        nbc->backing_bdev->bd_holders);
845                 retcode = ERR_BDCLAIM_DISK;
846                 goto fail;
847         }
848
849         resync_lru = lc_create("resync", drbd_bm_ext_cache,
850                         61, sizeof(struct bm_extent),
851                         offsetof(struct bm_extent, lce));
852         if (!resync_lru) {
853                 retcode = ERR_NOMEM;
854                 goto release_bdev_fail;
855         }
856
857         /* meta_dev_idx >= 0: external fixed size,
858          * possibly multiple drbd sharing one meta device.
859          * TODO in that case, paranoia check that [md_bdev, meta_dev_idx] is
860          * not yet used by some other drbd minor!
861          * (if you use drbd.conf + drbdadm,
862          * that should check it for you already; but if you don't, or someone
863          * fooled it, we need to double check here) */
864         nbc->md_bdev = inode2->i_bdev;
865         if (bd_claim(nbc->md_bdev, (nbc->dc.meta_dev_idx < 0) ? (void *)mdev
866                                 : (void *) drbd_m_holder)) {
867                 retcode = ERR_BDCLAIM_MD_DISK;
868                 goto release_bdev_fail;
869         }
870
871         if ((nbc->backing_bdev == nbc->md_bdev) !=
872             (nbc->dc.meta_dev_idx == DRBD_MD_INDEX_INTERNAL ||
873              nbc->dc.meta_dev_idx == DRBD_MD_INDEX_FLEX_INT)) {
874                 retcode = ERR_MD_IDX_INVALID;
875                 goto release_bdev2_fail;
876         }
877
878         /* RT - for drbd_get_max_capacity() DRBD_MD_INDEX_FLEX_INT */
879         drbd_md_set_sector_offsets(mdev, nbc);
880
881         if (drbd_get_max_capacity(nbc) < nbc->dc.disk_size) {
882                 dev_err(DEV, "max capacity %llu smaller than disk size %llu\n",
883                         (unsigned long long) drbd_get_max_capacity(nbc),
884                         (unsigned long long) nbc->dc.disk_size);
885                 retcode = ERR_DISK_TO_SMALL;
886                 goto release_bdev2_fail;
887         }
888
889         if (nbc->dc.meta_dev_idx < 0) {
890                 max_possible_sectors = DRBD_MAX_SECTORS_FLEX;
891                 /* at least one MB, otherwise it does not make sense */
892                 min_md_device_sectors = (2<<10);
893         } else {
894                 max_possible_sectors = DRBD_MAX_SECTORS;
895                 min_md_device_sectors = MD_RESERVED_SECT * (nbc->dc.meta_dev_idx + 1);
896         }
897
898         if (drbd_get_capacity(nbc->md_bdev) < min_md_device_sectors) {
899                 retcode = ERR_MD_DISK_TO_SMALL;
900                 dev_warn(DEV, "refusing attach: md-device too small, "
901                      "at least %llu sectors needed for this meta-disk type\n",
902                      (unsigned long long) min_md_device_sectors);
903                 goto release_bdev2_fail;
904         }
905
906         /* Make sure the new disk is big enough
907          * (we may currently be R_PRIMARY with no local disk...) */
908         if (drbd_get_max_capacity(nbc) <
909             drbd_get_capacity(mdev->this_bdev)) {
910                 retcode = ERR_DISK_TO_SMALL;
911                 goto release_bdev2_fail;
912         }
913
914         nbc->known_size = drbd_get_capacity(nbc->backing_bdev);
915
916         if (nbc->known_size > max_possible_sectors) {
917                 dev_warn(DEV, "==> truncating very big lower level device "
918                         "to currently maximum possible %llu sectors <==\n",
919                         (unsigned long long) max_possible_sectors);
920                 if (nbc->dc.meta_dev_idx >= 0)
921                         dev_warn(DEV, "==>> using internal or flexible "
922                                       "meta data may help <<==\n");
923         }
924
925         drbd_suspend_io(mdev);
926         /* also wait for the last barrier ack. */
927         wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_pending_cnt));
928         /* and for any other previously queued work */
929         drbd_flush_workqueue(mdev);
930
931         retcode = _drbd_request_state(mdev, NS(disk, D_ATTACHING), CS_VERBOSE);
932         drbd_resume_io(mdev);
933         if (retcode < SS_SUCCESS)
934                 goto release_bdev2_fail;
935
936         if (!get_ldev_if_state(mdev, D_ATTACHING))
937                 goto force_diskless;
938
939         drbd_md_set_sector_offsets(mdev, nbc);
940
941         /* allocate a second IO page if logical_block_size != 512 */
942         logical_block_size = bdev_logical_block_size(nbc->md_bdev);
943         if (logical_block_size == 0)
944                 logical_block_size = MD_SECTOR_SIZE;
945
946         if (logical_block_size != MD_SECTOR_SIZE) {
947                 if (!mdev->md_io_tmpp) {
948                         struct page *page = alloc_page(GFP_NOIO);
949                         if (!page)
950                                 goto force_diskless_dec;
951
952                         dev_warn(DEV, "Meta data's bdev logical_block_size = %d != %d\n",
953                              logical_block_size, MD_SECTOR_SIZE);
954                         dev_warn(DEV, "Workaround engaged (has performance impact).\n");
955
956                         mdev->md_io_tmpp = page;
957                 }
958         }
959
960         if (!mdev->bitmap) {
961                 if (drbd_bm_init(mdev)) {
962                         retcode = ERR_NOMEM;
963                         goto force_diskless_dec;
964                 }
965         }
966
967         retcode = drbd_md_read(mdev, nbc);
968         if (retcode != NO_ERROR)
969                 goto force_diskless_dec;
970
971         if (mdev->state.conn < C_CONNECTED &&
972             mdev->state.role == R_PRIMARY &&
973             (mdev->ed_uuid & ~((u64)1)) != (nbc->md.uuid[UI_CURRENT] & ~((u64)1))) {
974                 dev_err(DEV, "Can only attach to data with current UUID=%016llX\n",
975                     (unsigned long long)mdev->ed_uuid);
976                 retcode = ERR_DATA_NOT_CURRENT;
977                 goto force_diskless_dec;
978         }
979
980         /* Since we are diskless, fix the activity log first... */
981         if (drbd_check_al_size(mdev)) {
982                 retcode = ERR_NOMEM;
983                 goto force_diskless_dec;
984         }
985
986         /* Prevent shrinking of consistent devices ! */
987         if (drbd_md_test_flag(nbc, MDF_CONSISTENT) &&
988             drbd_new_dev_size(mdev, nbc, 0) < nbc->md.la_size_sect) {
989                 dev_warn(DEV, "refusing to truncate a consistent device\n");
990                 retcode = ERR_DISK_TO_SMALL;
991                 goto force_diskless_dec;
992         }
993
994         if (!drbd_al_read_log(mdev, nbc)) {
995                 retcode = ERR_IO_MD_DISK;
996                 goto force_diskless_dec;
997         }
998
999         /* Reset the "barriers don't work" bits here, then force meta data to
1000          * be written, to ensure we determine if barriers are supported. */
1001         if (nbc->dc.no_md_flush)
1002                 set_bit(MD_NO_BARRIER, &mdev->flags);
1003         else
1004                 clear_bit(MD_NO_BARRIER, &mdev->flags);
1005
1006         /* Point of no return reached.
1007          * Devices and memory are no longer released by error cleanup below.
1008          * now mdev takes over responsibility, and the state engine should
1009          * clean it up somewhere.  */
1010         D_ASSERT(mdev->ldev == NULL);
1011         mdev->ldev = nbc;
1012         mdev->resync = resync_lru;
1013         nbc = NULL;
1014         resync_lru = NULL;
1015
1016         mdev->write_ordering = WO_bio_barrier;
1017         drbd_bump_write_ordering(mdev, WO_bio_barrier);
1018
1019         if (drbd_md_test_flag(mdev->ldev, MDF_CRASHED_PRIMARY))
1020                 set_bit(CRASHED_PRIMARY, &mdev->flags);
1021         else
1022                 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1023
1024         if (drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND)) {
1025                 set_bit(CRASHED_PRIMARY, &mdev->flags);
1026                 cp_discovered = 1;
1027         }
1028
1029         mdev->send_cnt = 0;
1030         mdev->recv_cnt = 0;
1031         mdev->read_cnt = 0;
1032         mdev->writ_cnt = 0;
1033
1034         drbd_setup_queue_param(mdev, DRBD_MAX_SEGMENT_SIZE);
1035
1036         /* If I am currently not R_PRIMARY,
1037          * but meta data primary indicator is set,
1038          * I just now recover from a hard crash,
1039          * and have been R_PRIMARY before that crash.
1040          *
1041          * Now, if I had no connection before that crash
1042          * (have been degraded R_PRIMARY), chances are that
1043          * I won't find my peer now either.
1044          *
1045          * In that case, and _only_ in that case,
1046          * we use the degr-wfc-timeout instead of the default,
1047          * so we can automatically recover from a crash of a
1048          * degraded but active "cluster" after a certain timeout.
1049          */
1050         clear_bit(USE_DEGR_WFC_T, &mdev->flags);
1051         if (mdev->state.role != R_PRIMARY &&
1052              drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
1053             !drbd_md_test_flag(mdev->ldev, MDF_CONNECTED_IND))
1054                 set_bit(USE_DEGR_WFC_T, &mdev->flags);
1055
1056         dd = drbd_determin_dev_size(mdev, 0);
1057         if (dd == dev_size_error) {
1058                 retcode = ERR_NOMEM_BITMAP;
1059                 goto force_diskless_dec;
1060         } else if (dd == grew)
1061                 set_bit(RESYNC_AFTER_NEG, &mdev->flags);
1062
1063         if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
1064                 dev_info(DEV, "Assuming that all blocks are out of sync "
1065                      "(aka FullSync)\n");
1066                 if (drbd_bitmap_io(mdev, &drbd_bmio_set_n_write, "set_n_write from attaching")) {
1067                         retcode = ERR_IO_MD_DISK;
1068                         goto force_diskless_dec;
1069                 }
1070         } else {
1071                 if (drbd_bitmap_io(mdev, &drbd_bm_read, "read from attaching") < 0) {
1072                         retcode = ERR_IO_MD_DISK;
1073                         goto force_diskless_dec;
1074                 }
1075         }
1076
1077         if (cp_discovered) {
1078                 drbd_al_apply_to_bm(mdev);
1079                 drbd_al_to_on_disk_bm(mdev);
1080         }
1081
1082         spin_lock_irq(&mdev->req_lock);
1083         os = mdev->state;
1084         ns.i = os.i;
1085         /* If MDF_CONSISTENT is not set go into inconsistent state,
1086            otherwise investigate MDF_WasUpToDate...
1087            If MDF_WAS_UP_TO_DATE is not set go into D_OUTDATED disk state,
1088            otherwise into D_CONSISTENT state.
1089         */
1090         if (drbd_md_test_flag(mdev->ldev, MDF_CONSISTENT)) {
1091                 if (drbd_md_test_flag(mdev->ldev, MDF_WAS_UP_TO_DATE))
1092                         ns.disk = D_CONSISTENT;
1093                 else
1094                         ns.disk = D_OUTDATED;
1095         } else {
1096                 ns.disk = D_INCONSISTENT;
1097         }
1098
1099         if (drbd_md_test_flag(mdev->ldev, MDF_PEER_OUT_DATED))
1100                 ns.pdsk = D_OUTDATED;
1101
1102         if ( ns.disk == D_CONSISTENT &&
1103             (ns.pdsk == D_OUTDATED || mdev->ldev->dc.fencing == FP_DONT_CARE))
1104                 ns.disk = D_UP_TO_DATE;
1105
1106         /* All tests on MDF_PRIMARY_IND, MDF_CONNECTED_IND,
1107            MDF_CONSISTENT and MDF_WAS_UP_TO_DATE must happen before
1108            this point, because drbd_request_state() modifies these
1109            flags. */
1110
1111         /* In case we are C_CONNECTED postpone any decision on the new disk
1112            state after the negotiation phase. */
1113         if (mdev->state.conn == C_CONNECTED) {
1114                 mdev->new_state_tmp.i = ns.i;
1115                 ns.i = os.i;
1116                 ns.disk = D_NEGOTIATING;
1117         }
1118
1119         rv = _drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
1120         ns = mdev->state;
1121         spin_unlock_irq(&mdev->req_lock);
1122
1123         if (rv < SS_SUCCESS)
1124                 goto force_diskless_dec;
1125
1126         if (mdev->state.role == R_PRIMARY)
1127                 mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
1128         else
1129                 mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
1130
1131         drbd_md_mark_dirty(mdev);
1132         drbd_md_sync(mdev);
1133
1134         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1135         put_ldev(mdev);
1136         reply->ret_code = retcode;
1137         drbd_reconfig_done(mdev);
1138         return 0;
1139
1140  force_diskless_dec:
1141         put_ldev(mdev);
1142  force_diskless:
1143         drbd_force_state(mdev, NS(disk, D_DISKLESS));
1144         drbd_md_sync(mdev);
1145  release_bdev2_fail:
1146         if (nbc)
1147                 bd_release(nbc->md_bdev);
1148  release_bdev_fail:
1149         if (nbc)
1150                 bd_release(nbc->backing_bdev);
1151  fail:
1152         if (nbc) {
1153                 if (nbc->lo_file)
1154                         fput(nbc->lo_file);
1155                 if (nbc->md_file)
1156                         fput(nbc->md_file);
1157                 kfree(nbc);
1158         }
1159         lc_destroy(resync_lru);
1160
1161         reply->ret_code = retcode;
1162         drbd_reconfig_done(mdev);
1163         return 0;
1164 }
1165
1166 static int drbd_nl_detach(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1167                           struct drbd_nl_cfg_reply *reply)
1168 {
1169         reply->ret_code = drbd_request_state(mdev, NS(disk, D_DISKLESS));
1170         return 0;
1171 }
1172
1173 static int drbd_nl_net_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1174                             struct drbd_nl_cfg_reply *reply)
1175 {
1176         int i, ns;
1177         enum drbd_ret_codes retcode;
1178         struct net_conf *new_conf = NULL;
1179         struct crypto_hash *tfm = NULL;
1180         struct crypto_hash *integrity_w_tfm = NULL;
1181         struct crypto_hash *integrity_r_tfm = NULL;
1182         struct hlist_head *new_tl_hash = NULL;
1183         struct hlist_head *new_ee_hash = NULL;
1184         struct drbd_conf *odev;
1185         char hmac_name[CRYPTO_MAX_ALG_NAME];
1186         void *int_dig_out = NULL;
1187         void *int_dig_in = NULL;
1188         void *int_dig_vv = NULL;
1189         struct sockaddr *new_my_addr, *new_peer_addr, *taken_addr;
1190
1191         drbd_reconfig_start(mdev);
1192
1193         if (mdev->state.conn > C_STANDALONE) {
1194                 retcode = ERR_NET_CONFIGURED;
1195                 goto fail;
1196         }
1197
1198         /* allocation not in the IO path, cqueue thread context */
1199         new_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
1200         if (!new_conf) {
1201                 retcode = ERR_NOMEM;
1202                 goto fail;
1203         }
1204
1205         new_conf->timeout          = DRBD_TIMEOUT_DEF;
1206         new_conf->try_connect_int  = DRBD_CONNECT_INT_DEF;
1207         new_conf->ping_int         = DRBD_PING_INT_DEF;
1208         new_conf->max_epoch_size   = DRBD_MAX_EPOCH_SIZE_DEF;
1209         new_conf->max_buffers      = DRBD_MAX_BUFFERS_DEF;
1210         new_conf->unplug_watermark = DRBD_UNPLUG_WATERMARK_DEF;
1211         new_conf->sndbuf_size      = DRBD_SNDBUF_SIZE_DEF;
1212         new_conf->rcvbuf_size      = DRBD_RCVBUF_SIZE_DEF;
1213         new_conf->ko_count         = DRBD_KO_COUNT_DEF;
1214         new_conf->after_sb_0p      = DRBD_AFTER_SB_0P_DEF;
1215         new_conf->after_sb_1p      = DRBD_AFTER_SB_1P_DEF;
1216         new_conf->after_sb_2p      = DRBD_AFTER_SB_2P_DEF;
1217         new_conf->want_lose        = 0;
1218         new_conf->two_primaries    = 0;
1219         new_conf->wire_protocol    = DRBD_PROT_C;
1220         new_conf->ping_timeo       = DRBD_PING_TIMEO_DEF;
1221         new_conf->rr_conflict      = DRBD_RR_CONFLICT_DEF;
1222
1223         if (!net_conf_from_tags(mdev, nlp->tag_list, new_conf)) {
1224                 retcode = ERR_MANDATORY_TAG;
1225                 goto fail;
1226         }
1227
1228         if (new_conf->two_primaries
1229             && (new_conf->wire_protocol != DRBD_PROT_C)) {
1230                 retcode = ERR_NOT_PROTO_C;
1231                 goto fail;
1232         };
1233
1234         if (mdev->state.role == R_PRIMARY && new_conf->want_lose) {
1235                 retcode = ERR_DISCARD;
1236                 goto fail;
1237         }
1238
1239         retcode = NO_ERROR;
1240
1241         new_my_addr = (struct sockaddr *)&new_conf->my_addr;
1242         new_peer_addr = (struct sockaddr *)&new_conf->peer_addr;
1243         for (i = 0; i < minor_count; i++) {
1244                 odev = minor_to_mdev(i);
1245                 if (!odev || odev == mdev)
1246                         continue;
1247                 if (get_net_conf(odev)) {
1248                         taken_addr = (struct sockaddr *)&odev->net_conf->my_addr;
1249                         if (new_conf->my_addr_len == odev->net_conf->my_addr_len &&
1250                             !memcmp(new_my_addr, taken_addr, new_conf->my_addr_len))
1251                                 retcode = ERR_LOCAL_ADDR;
1252
1253                         taken_addr = (struct sockaddr *)&odev->net_conf->peer_addr;
1254                         if (new_conf->peer_addr_len == odev->net_conf->peer_addr_len &&
1255                             !memcmp(new_peer_addr, taken_addr, new_conf->peer_addr_len))
1256                                 retcode = ERR_PEER_ADDR;
1257
1258                         put_net_conf(odev);
1259                         if (retcode != NO_ERROR)
1260                                 goto fail;
1261                 }
1262         }
1263
1264         if (new_conf->cram_hmac_alg[0] != 0) {
1265                 snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",
1266                         new_conf->cram_hmac_alg);
1267                 tfm = crypto_alloc_hash(hmac_name, 0, CRYPTO_ALG_ASYNC);
1268                 if (IS_ERR(tfm)) {
1269                         tfm = NULL;
1270                         retcode = ERR_AUTH_ALG;
1271                         goto fail;
1272                 }
1273
1274                 if (!drbd_crypto_is_hash(crypto_hash_tfm(tfm))) {
1275                         retcode = ERR_AUTH_ALG_ND;
1276                         goto fail;
1277                 }
1278         }
1279
1280         if (new_conf->integrity_alg[0]) {
1281                 integrity_w_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1282                 if (IS_ERR(integrity_w_tfm)) {
1283                         integrity_w_tfm = NULL;
1284                         retcode=ERR_INTEGRITY_ALG;
1285                         goto fail;
1286                 }
1287
1288                 if (!drbd_crypto_is_hash(crypto_hash_tfm(integrity_w_tfm))) {
1289                         retcode=ERR_INTEGRITY_ALG_ND;
1290                         goto fail;
1291                 }
1292
1293                 integrity_r_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1294                 if (IS_ERR(integrity_r_tfm)) {
1295                         integrity_r_tfm = NULL;
1296                         retcode=ERR_INTEGRITY_ALG;
1297                         goto fail;
1298                 }
1299         }
1300
1301         ns = new_conf->max_epoch_size/8;
1302         if (mdev->tl_hash_s != ns) {
1303                 new_tl_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1304                 if (!new_tl_hash) {
1305                         retcode = ERR_NOMEM;
1306                         goto fail;
1307                 }
1308         }
1309
1310         ns = new_conf->max_buffers/8;
1311         if (new_conf->two_primaries && (mdev->ee_hash_s != ns)) {
1312                 new_ee_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1313                 if (!new_ee_hash) {
1314                         retcode = ERR_NOMEM;
1315                         goto fail;
1316                 }
1317         }
1318
1319         ((char *)new_conf->shared_secret)[SHARED_SECRET_MAX-1] = 0;
1320
1321         if (integrity_w_tfm) {
1322                 i = crypto_hash_digestsize(integrity_w_tfm);
1323                 int_dig_out = kmalloc(i, GFP_KERNEL);
1324                 if (!int_dig_out) {
1325                         retcode = ERR_NOMEM;
1326                         goto fail;
1327                 }
1328                 int_dig_in = kmalloc(i, GFP_KERNEL);
1329                 if (!int_dig_in) {
1330                         retcode = ERR_NOMEM;
1331                         goto fail;
1332                 }
1333                 int_dig_vv = kmalloc(i, GFP_KERNEL);
1334                 if (!int_dig_vv) {
1335                         retcode = ERR_NOMEM;
1336                         goto fail;
1337                 }
1338         }
1339
1340         if (!mdev->bitmap) {
1341                 if(drbd_bm_init(mdev)) {
1342                         retcode = ERR_NOMEM;
1343                         goto fail;
1344                 }
1345         }
1346
1347         spin_lock_irq(&mdev->req_lock);
1348         if (mdev->net_conf != NULL) {
1349                 retcode = ERR_NET_CONFIGURED;
1350                 spin_unlock_irq(&mdev->req_lock);
1351                 goto fail;
1352         }
1353         mdev->net_conf = new_conf;
1354
1355         mdev->send_cnt = 0;
1356         mdev->recv_cnt = 0;
1357
1358         if (new_tl_hash) {
1359                 kfree(mdev->tl_hash);
1360                 mdev->tl_hash_s = mdev->net_conf->max_epoch_size/8;
1361                 mdev->tl_hash = new_tl_hash;
1362         }
1363
1364         if (new_ee_hash) {
1365                 kfree(mdev->ee_hash);
1366                 mdev->ee_hash_s = mdev->net_conf->max_buffers/8;
1367                 mdev->ee_hash = new_ee_hash;
1368         }
1369
1370         crypto_free_hash(mdev->cram_hmac_tfm);
1371         mdev->cram_hmac_tfm = tfm;
1372
1373         crypto_free_hash(mdev->integrity_w_tfm);
1374         mdev->integrity_w_tfm = integrity_w_tfm;
1375
1376         crypto_free_hash(mdev->integrity_r_tfm);
1377         mdev->integrity_r_tfm = integrity_r_tfm;
1378
1379         kfree(mdev->int_dig_out);
1380         kfree(mdev->int_dig_in);
1381         kfree(mdev->int_dig_vv);
1382         mdev->int_dig_out=int_dig_out;
1383         mdev->int_dig_in=int_dig_in;
1384         mdev->int_dig_vv=int_dig_vv;
1385         spin_unlock_irq(&mdev->req_lock);
1386
1387         retcode = _drbd_request_state(mdev, NS(conn, C_UNCONNECTED), CS_VERBOSE);
1388
1389         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1390         reply->ret_code = retcode;
1391         drbd_reconfig_done(mdev);
1392         return 0;
1393
1394 fail:
1395         kfree(int_dig_out);
1396         kfree(int_dig_in);
1397         kfree(int_dig_vv);
1398         crypto_free_hash(tfm);
1399         crypto_free_hash(integrity_w_tfm);
1400         crypto_free_hash(integrity_r_tfm);
1401         kfree(new_tl_hash);
1402         kfree(new_ee_hash);
1403         kfree(new_conf);
1404
1405         reply->ret_code = retcode;
1406         drbd_reconfig_done(mdev);
1407         return 0;
1408 }
1409
1410 static int drbd_nl_disconnect(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1411                               struct drbd_nl_cfg_reply *reply)
1412 {
1413         int retcode;
1414
1415         retcode = _drbd_request_state(mdev, NS(conn, C_DISCONNECTING), CS_ORDERED);
1416
1417         if (retcode == SS_NOTHING_TO_DO)
1418                 goto done;
1419         else if (retcode == SS_ALREADY_STANDALONE)
1420                 goto done;
1421         else if (retcode == SS_PRIMARY_NOP) {
1422                 /* Our statche checking code wants to see the peer outdated. */
1423                 retcode = drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1424                                                       pdsk, D_OUTDATED));
1425         } else if (retcode == SS_CW_FAILED_BY_PEER) {
1426                 /* The peer probably wants to see us outdated. */
1427                 retcode = _drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1428                                                         disk, D_OUTDATED),
1429                                               CS_ORDERED);
1430                 if (retcode == SS_IS_DISKLESS || retcode == SS_LOWER_THAN_OUTDATED) {
1431                         drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
1432                         retcode = SS_SUCCESS;
1433                 }
1434         }
1435
1436         if (retcode < SS_SUCCESS)
1437                 goto fail;
1438
1439         if (wait_event_interruptible(mdev->state_wait,
1440                                      mdev->state.conn != C_DISCONNECTING)) {
1441                 /* Do not test for mdev->state.conn == C_STANDALONE, since
1442                    someone else might connect us in the mean time! */
1443                 retcode = ERR_INTR;
1444                 goto fail;
1445         }
1446
1447  done:
1448         retcode = NO_ERROR;
1449  fail:
1450         drbd_md_sync(mdev);
1451         reply->ret_code = retcode;
1452         return 0;
1453 }
1454
1455 void resync_after_online_grow(struct drbd_conf *mdev)
1456 {
1457         int iass; /* I am sync source */
1458
1459         dev_info(DEV, "Resync of new storage after online grow\n");
1460         if (mdev->state.role != mdev->state.peer)
1461                 iass = (mdev->state.role == R_PRIMARY);
1462         else
1463                 iass = test_bit(DISCARD_CONCURRENT, &mdev->flags);
1464
1465         if (iass)
1466                 drbd_start_resync(mdev, C_SYNC_SOURCE);
1467         else
1468                 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE + CS_SERIALIZE);
1469 }
1470
1471 static int drbd_nl_resize(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1472                           struct drbd_nl_cfg_reply *reply)
1473 {
1474         struct resize rs;
1475         int retcode = NO_ERROR;
1476         enum determine_dev_size dd;
1477         enum dds_flags ddsf;
1478
1479         memset(&rs, 0, sizeof(struct resize));
1480         if (!resize_from_tags(mdev, nlp->tag_list, &rs)) {
1481                 retcode = ERR_MANDATORY_TAG;
1482                 goto fail;
1483         }
1484
1485         if (mdev->state.conn > C_CONNECTED) {
1486                 retcode = ERR_RESIZE_RESYNC;
1487                 goto fail;
1488         }
1489
1490         if (mdev->state.role == R_SECONDARY &&
1491             mdev->state.peer == R_SECONDARY) {
1492                 retcode = ERR_NO_PRIMARY;
1493                 goto fail;
1494         }
1495
1496         if (!get_ldev(mdev)) {
1497                 retcode = ERR_NO_DISK;
1498                 goto fail;
1499         }
1500
1501         if (rs.no_resync && mdev->agreed_pro_version < 93) {
1502                 retcode = ERR_NEED_APV_93;
1503                 goto fail;
1504         }
1505
1506         if (mdev->ldev->known_size != drbd_get_capacity(mdev->ldev->backing_bdev))
1507                 mdev->ldev->known_size = drbd_get_capacity(mdev->ldev->backing_bdev);
1508
1509         mdev->ldev->dc.disk_size = (sector_t)rs.resize_size;
1510         ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
1511         dd = drbd_determin_dev_size(mdev, ddsf);
1512         drbd_md_sync(mdev);
1513         put_ldev(mdev);
1514         if (dd == dev_size_error) {
1515                 retcode = ERR_NOMEM_BITMAP;
1516                 goto fail;
1517         }
1518
1519         if (mdev->state.conn == C_CONNECTED) {
1520                 if (dd == grew)
1521                         set_bit(RESIZE_PENDING, &mdev->flags);
1522
1523                 drbd_send_uuids(mdev);
1524                 drbd_send_sizes(mdev, 1, ddsf);
1525         }
1526
1527  fail:
1528         reply->ret_code = retcode;
1529         return 0;
1530 }
1531
1532 static int drbd_nl_syncer_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1533                                struct drbd_nl_cfg_reply *reply)
1534 {
1535         int retcode = NO_ERROR;
1536         int err;
1537         int ovr; /* online verify running */
1538         int rsr; /* re-sync running */
1539         struct crypto_hash *verify_tfm = NULL;
1540         struct crypto_hash *csums_tfm = NULL;
1541         struct syncer_conf sc;
1542         cpumask_var_t new_cpu_mask;
1543
1544         if (!zalloc_cpumask_var(&new_cpu_mask, GFP_KERNEL)) {
1545                 retcode = ERR_NOMEM;
1546                 goto fail;
1547         }
1548
1549         if (nlp->flags & DRBD_NL_SET_DEFAULTS) {
1550                 memset(&sc, 0, sizeof(struct syncer_conf));
1551                 sc.rate       = DRBD_RATE_DEF;
1552                 sc.after      = DRBD_AFTER_DEF;
1553                 sc.al_extents = DRBD_AL_EXTENTS_DEF;
1554                 sc.dp_volume  = DRBD_DP_VOLUME_DEF;
1555                 sc.dp_interval = DRBD_DP_INTERVAL_DEF;
1556                 sc.throttle_th = DRBD_RS_THROTTLE_TH_DEF;
1557                 sc.hold_off_th = DRBD_RS_HOLD_OFF_TH_DEF;
1558         } else
1559                 memcpy(&sc, &mdev->sync_conf, sizeof(struct syncer_conf));
1560
1561         if (!syncer_conf_from_tags(mdev, nlp->tag_list, &sc)) {
1562                 retcode = ERR_MANDATORY_TAG;
1563                 goto fail;
1564         }
1565
1566         /* re-sync running */
1567         rsr = ( mdev->state.conn == C_SYNC_SOURCE ||
1568                 mdev->state.conn == C_SYNC_TARGET ||
1569                 mdev->state.conn == C_PAUSED_SYNC_S ||
1570                 mdev->state.conn == C_PAUSED_SYNC_T );
1571
1572         if (rsr && strcmp(sc.csums_alg, mdev->sync_conf.csums_alg)) {
1573                 retcode = ERR_CSUMS_RESYNC_RUNNING;
1574                 goto fail;
1575         }
1576
1577         if (!rsr && sc.csums_alg[0]) {
1578                 csums_tfm = crypto_alloc_hash(sc.csums_alg, 0, CRYPTO_ALG_ASYNC);
1579                 if (IS_ERR(csums_tfm)) {
1580                         csums_tfm = NULL;
1581                         retcode = ERR_CSUMS_ALG;
1582                         goto fail;
1583                 }
1584
1585                 if (!drbd_crypto_is_hash(crypto_hash_tfm(csums_tfm))) {
1586                         retcode = ERR_CSUMS_ALG_ND;
1587                         goto fail;
1588                 }
1589         }
1590
1591         /* online verify running */
1592         ovr = (mdev->state.conn == C_VERIFY_S || mdev->state.conn == C_VERIFY_T);
1593
1594         if (ovr) {
1595                 if (strcmp(sc.verify_alg, mdev->sync_conf.verify_alg)) {
1596                         retcode = ERR_VERIFY_RUNNING;
1597                         goto fail;
1598                 }
1599         }
1600
1601         if (!ovr && sc.verify_alg[0]) {
1602                 verify_tfm = crypto_alloc_hash(sc.verify_alg, 0, CRYPTO_ALG_ASYNC);
1603                 if (IS_ERR(verify_tfm)) {
1604                         verify_tfm = NULL;
1605                         retcode = ERR_VERIFY_ALG;
1606                         goto fail;
1607                 }
1608
1609                 if (!drbd_crypto_is_hash(crypto_hash_tfm(verify_tfm))) {
1610                         retcode = ERR_VERIFY_ALG_ND;
1611                         goto fail;
1612                 }
1613         }
1614
1615         /* silently ignore cpu mask on UP kernel */
1616         if (nr_cpu_ids > 1 && sc.cpu_mask[0] != 0) {
1617                 err = __bitmap_parse(sc.cpu_mask, 32, 0,
1618                                 cpumask_bits(new_cpu_mask), nr_cpu_ids);
1619                 if (err) {
1620                         dev_warn(DEV, "__bitmap_parse() failed with %d\n", err);
1621                         retcode = ERR_CPU_MASK_PARSE;
1622                         goto fail;
1623                 }
1624         }
1625
1626         ERR_IF (sc.rate < 1) sc.rate = 1;
1627         ERR_IF (sc.al_extents < 7) sc.al_extents = 127; /* arbitrary minimum */
1628 #define AL_MAX ((MD_AL_MAX_SIZE-1) * AL_EXTENTS_PT)
1629         if (sc.al_extents > AL_MAX) {
1630                 dev_err(DEV, "sc.al_extents > %d\n", AL_MAX);
1631                 sc.al_extents = AL_MAX;
1632         }
1633 #undef AL_MAX
1634
1635         /* most sanity checks done, try to assign the new sync-after
1636          * dependency.  need to hold the global lock in there,
1637          * to avoid a race in the dependency loop check. */
1638         retcode = drbd_alter_sa(mdev, sc.after);
1639         if (retcode != NO_ERROR)
1640                 goto fail;
1641
1642         /* ok, assign the rest of it as well.
1643          * lock against receive_SyncParam() */
1644         spin_lock(&mdev->peer_seq_lock);
1645         mdev->sync_conf = sc;
1646
1647         if (!rsr) {
1648                 crypto_free_hash(mdev->csums_tfm);
1649                 mdev->csums_tfm = csums_tfm;
1650                 csums_tfm = NULL;
1651         }
1652
1653         if (!ovr) {
1654                 crypto_free_hash(mdev->verify_tfm);
1655                 mdev->verify_tfm = verify_tfm;
1656                 verify_tfm = NULL;
1657         }
1658         spin_unlock(&mdev->peer_seq_lock);
1659
1660         if (get_ldev(mdev)) {
1661                 wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
1662                 drbd_al_shrink(mdev);
1663                 err = drbd_check_al_size(mdev);
1664                 lc_unlock(mdev->act_log);
1665                 wake_up(&mdev->al_wait);
1666
1667                 put_ldev(mdev);
1668                 drbd_md_sync(mdev);
1669
1670                 if (err) {
1671                         retcode = ERR_NOMEM;
1672                         goto fail;
1673                 }
1674         }
1675
1676         if (mdev->state.conn >= C_CONNECTED)
1677                 drbd_send_sync_param(mdev, &sc);
1678
1679         if (!cpumask_equal(mdev->cpu_mask, new_cpu_mask)) {
1680                 cpumask_copy(mdev->cpu_mask, new_cpu_mask);
1681                 drbd_calc_cpu_mask(mdev);
1682                 mdev->receiver.reset_cpu_mask = 1;
1683                 mdev->asender.reset_cpu_mask = 1;
1684                 mdev->worker.reset_cpu_mask = 1;
1685         }
1686
1687         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1688 fail:
1689         free_cpumask_var(new_cpu_mask);
1690         crypto_free_hash(csums_tfm);
1691         crypto_free_hash(verify_tfm);
1692         reply->ret_code = retcode;
1693         return 0;
1694 }
1695
1696 static int drbd_nl_invalidate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1697                               struct drbd_nl_cfg_reply *reply)
1698 {
1699         int retcode;
1700
1701         retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T), CS_ORDERED);
1702
1703         if (retcode < SS_SUCCESS && retcode != SS_NEED_CONNECTION)
1704                 retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1705
1706         while (retcode == SS_NEED_CONNECTION) {
1707                 spin_lock_irq(&mdev->req_lock);
1708                 if (mdev->state.conn < C_CONNECTED)
1709                         retcode = _drbd_set_state(_NS(mdev, disk, D_INCONSISTENT), CS_VERBOSE, NULL);
1710                 spin_unlock_irq(&mdev->req_lock);
1711
1712                 if (retcode != SS_NEED_CONNECTION)
1713                         break;
1714
1715                 retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1716         }
1717
1718         reply->ret_code = retcode;
1719         return 0;
1720 }
1721
1722 static int drbd_nl_invalidate_peer(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1723                                    struct drbd_nl_cfg_reply *reply)
1724 {
1725
1726         reply->ret_code = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S));
1727
1728         return 0;
1729 }
1730
1731 static int drbd_nl_pause_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1732                               struct drbd_nl_cfg_reply *reply)
1733 {
1734         int retcode = NO_ERROR;
1735
1736         if (drbd_request_state(mdev, NS(user_isp, 1)) == SS_NOTHING_TO_DO)
1737                 retcode = ERR_PAUSE_IS_SET;
1738
1739         reply->ret_code = retcode;
1740         return 0;
1741 }
1742
1743 static int drbd_nl_resume_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1744                                struct drbd_nl_cfg_reply *reply)
1745 {
1746         int retcode = NO_ERROR;
1747
1748         if (drbd_request_state(mdev, NS(user_isp, 0)) == SS_NOTHING_TO_DO)
1749                 retcode = ERR_PAUSE_IS_CLEAR;
1750
1751         reply->ret_code = retcode;
1752         return 0;
1753 }
1754
1755 static int drbd_nl_suspend_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1756                               struct drbd_nl_cfg_reply *reply)
1757 {
1758         reply->ret_code = drbd_request_state(mdev, NS(susp, 1));
1759
1760         return 0;
1761 }
1762
1763 static int drbd_nl_resume_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1764                              struct drbd_nl_cfg_reply *reply)
1765 {
1766         reply->ret_code = drbd_request_state(mdev, NS(susp, 0));
1767         return 0;
1768 }
1769
1770 static int drbd_nl_outdate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1771                            struct drbd_nl_cfg_reply *reply)
1772 {
1773         reply->ret_code = drbd_request_state(mdev, NS(disk, D_OUTDATED));
1774         return 0;
1775 }
1776
1777 static int drbd_nl_get_config(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1778                            struct drbd_nl_cfg_reply *reply)
1779 {
1780         unsigned short *tl;
1781
1782         tl = reply->tag_list;
1783
1784         if (get_ldev(mdev)) {
1785                 tl = disk_conf_to_tags(mdev, &mdev->ldev->dc, tl);
1786                 put_ldev(mdev);
1787         }
1788
1789         if (get_net_conf(mdev)) {
1790                 tl = net_conf_to_tags(mdev, mdev->net_conf, tl);
1791                 put_net_conf(mdev);
1792         }
1793         tl = syncer_conf_to_tags(mdev, &mdev->sync_conf, tl);
1794
1795         put_unaligned(TT_END, tl++); /* Close the tag list */
1796
1797         return (int)((char *)tl - (char *)reply->tag_list);
1798 }
1799
1800 static int drbd_nl_get_state(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1801                              struct drbd_nl_cfg_reply *reply)
1802 {
1803         unsigned short *tl = reply->tag_list;
1804         union drbd_state s = mdev->state;
1805         unsigned long rs_left;
1806         unsigned int res;
1807
1808         tl = get_state_to_tags(mdev, (struct get_state *)&s, tl);
1809
1810         /* no local ref, no bitmap, no syncer progress. */
1811         if (s.conn >= C_SYNC_SOURCE && s.conn <= C_PAUSED_SYNC_T) {
1812                 if (get_ldev(mdev)) {
1813                         drbd_get_syncer_progress(mdev, &rs_left, &res);
1814                         tl = tl_add_int(tl, T_sync_progress, &res);
1815                         put_ldev(mdev);
1816                 }
1817         }
1818         put_unaligned(TT_END, tl++); /* Close the tag list */
1819
1820         return (int)((char *)tl - (char *)reply->tag_list);
1821 }
1822
1823 static int drbd_nl_get_uuids(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1824                              struct drbd_nl_cfg_reply *reply)
1825 {
1826         unsigned short *tl;
1827
1828         tl = reply->tag_list;
1829
1830         if (get_ldev(mdev)) {
1831                 tl = tl_add_blob(tl, T_uuids, mdev->ldev->md.uuid, UI_SIZE*sizeof(u64));
1832                 tl = tl_add_int(tl, T_uuids_flags, &mdev->ldev->md.flags);
1833                 put_ldev(mdev);
1834         }
1835         put_unaligned(TT_END, tl++); /* Close the tag list */
1836
1837         return (int)((char *)tl - (char *)reply->tag_list);
1838 }
1839
1840 /**
1841  * drbd_nl_get_timeout_flag() - Used by drbdsetup to find out which timeout value to use
1842  * @mdev:       DRBD device.
1843  * @nlp:        Netlink/connector packet from drbdsetup
1844  * @reply:      Reply packet for drbdsetup
1845  */
1846 static int drbd_nl_get_timeout_flag(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1847                                     struct drbd_nl_cfg_reply *reply)
1848 {
1849         unsigned short *tl;
1850         char rv;
1851
1852         tl = reply->tag_list;
1853
1854         rv = mdev->state.pdsk == D_OUTDATED        ? UT_PEER_OUTDATED :
1855           test_bit(USE_DEGR_WFC_T, &mdev->flags) ? UT_DEGRADED : UT_DEFAULT;
1856
1857         tl = tl_add_blob(tl, T_use_degraded, &rv, sizeof(rv));
1858         put_unaligned(TT_END, tl++); /* Close the tag list */
1859
1860         return (int)((char *)tl - (char *)reply->tag_list);
1861 }
1862
1863 static int drbd_nl_start_ov(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1864                                     struct drbd_nl_cfg_reply *reply)
1865 {
1866         /* default to resume from last known position, if possible */
1867         struct start_ov args =
1868                 { .start_sector = mdev->ov_start_sector };
1869
1870         if (!start_ov_from_tags(mdev, nlp->tag_list, &args)) {
1871                 reply->ret_code = ERR_MANDATORY_TAG;
1872                 return 0;
1873         }
1874         /* w_make_ov_request expects position to be aligned */
1875         mdev->ov_start_sector = args.start_sector & ~BM_SECT_PER_BIT;
1876         reply->ret_code = drbd_request_state(mdev,NS(conn,C_VERIFY_S));
1877         return 0;
1878 }
1879
1880
1881 static int drbd_nl_new_c_uuid(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1882                               struct drbd_nl_cfg_reply *reply)
1883 {
1884         int retcode = NO_ERROR;
1885         int skip_initial_sync = 0;
1886         int err;
1887
1888         struct new_c_uuid args;
1889
1890         memset(&args, 0, sizeof(struct new_c_uuid));
1891         if (!new_c_uuid_from_tags(mdev, nlp->tag_list, &args)) {
1892                 reply->ret_code = ERR_MANDATORY_TAG;
1893                 return 0;
1894         }
1895
1896         mutex_lock(&mdev->state_mutex); /* Protects us against serialized state changes. */
1897
1898         if (!get_ldev(mdev)) {
1899                 retcode = ERR_NO_DISK;
1900                 goto out;
1901         }
1902
1903         /* this is "skip initial sync", assume to be clean */
1904         if (mdev->state.conn == C_CONNECTED && mdev->agreed_pro_version >= 90 &&
1905             mdev->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED && args.clear_bm) {
1906                 dev_info(DEV, "Preparing to skip initial sync\n");
1907                 skip_initial_sync = 1;
1908         } else if (mdev->state.conn != C_STANDALONE) {
1909                 retcode = ERR_CONNECTED;
1910                 goto out_dec;
1911         }
1912
1913         drbd_uuid_set(mdev, UI_BITMAP, 0); /* Rotate UI_BITMAP to History 1, etc... */
1914         drbd_uuid_new_current(mdev); /* New current, previous to UI_BITMAP */
1915
1916         if (args.clear_bm) {
1917                 err = drbd_bitmap_io(mdev, &drbd_bmio_clear_n_write, "clear_n_write from new_c_uuid");
1918                 if (err) {
1919                         dev_err(DEV, "Writing bitmap failed with %d\n",err);
1920                         retcode = ERR_IO_MD_DISK;
1921                 }
1922                 if (skip_initial_sync) {
1923                         drbd_send_uuids_skip_initial_sync(mdev);
1924                         _drbd_uuid_set(mdev, UI_BITMAP, 0);
1925                         spin_lock_irq(&mdev->req_lock);
1926                         _drbd_set_state(_NS2(mdev, disk, D_UP_TO_DATE, pdsk, D_UP_TO_DATE),
1927                                         CS_VERBOSE, NULL);
1928                         spin_unlock_irq(&mdev->req_lock);
1929                 }
1930         }
1931
1932         drbd_md_sync(mdev);
1933 out_dec:
1934         put_ldev(mdev);
1935 out:
1936         mutex_unlock(&mdev->state_mutex);
1937
1938         reply->ret_code = retcode;
1939         return 0;
1940 }
1941
1942 static struct drbd_conf *ensure_mdev(struct drbd_nl_cfg_req *nlp)
1943 {
1944         struct drbd_conf *mdev;
1945
1946         if (nlp->drbd_minor >= minor_count)
1947                 return NULL;
1948
1949         mdev = minor_to_mdev(nlp->drbd_minor);
1950
1951         if (!mdev && (nlp->flags & DRBD_NL_CREATE_DEVICE)) {
1952                 struct gendisk *disk = NULL;
1953                 mdev = drbd_new_device(nlp->drbd_minor);
1954
1955                 spin_lock_irq(&drbd_pp_lock);
1956                 if (minor_table[nlp->drbd_minor] == NULL) {
1957                         minor_table[nlp->drbd_minor] = mdev;
1958                         disk = mdev->vdisk;
1959                         mdev = NULL;
1960                 } /* else: we lost the race */
1961                 spin_unlock_irq(&drbd_pp_lock);
1962
1963                 if (disk) /* we won the race above */
1964                         /* in case we ever add a drbd_delete_device(),
1965                          * don't forget the del_gendisk! */
1966                         add_disk(disk);
1967                 else /* we lost the race above */
1968                         drbd_free_mdev(mdev);
1969
1970                 mdev = minor_to_mdev(nlp->drbd_minor);
1971         }
1972
1973         return mdev;
1974 }
1975
1976 struct cn_handler_struct {
1977         int (*function)(struct drbd_conf *,
1978                          struct drbd_nl_cfg_req *,
1979                          struct drbd_nl_cfg_reply *);
1980         int reply_body_size;
1981 };
1982
1983 static struct cn_handler_struct cnd_table[] = {
1984         [ P_primary ]           = { &drbd_nl_primary,           0 },
1985         [ P_secondary ]         = { &drbd_nl_secondary,         0 },
1986         [ P_disk_conf ]         = { &drbd_nl_disk_conf,         0 },
1987         [ P_detach ]            = { &drbd_nl_detach,            0 },
1988         [ P_net_conf ]          = { &drbd_nl_net_conf,          0 },
1989         [ P_disconnect ]        = { &drbd_nl_disconnect,        0 },
1990         [ P_resize ]            = { &drbd_nl_resize,            0 },
1991         [ P_syncer_conf ]       = { &drbd_nl_syncer_conf,       0 },
1992         [ P_invalidate ]        = { &drbd_nl_invalidate,        0 },
1993         [ P_invalidate_peer ]   = { &drbd_nl_invalidate_peer,   0 },
1994         [ P_pause_sync ]        = { &drbd_nl_pause_sync,        0 },
1995         [ P_resume_sync ]       = { &drbd_nl_resume_sync,       0 },
1996         [ P_suspend_io ]        = { &drbd_nl_suspend_io,        0 },
1997         [ P_resume_io ]         = { &drbd_nl_resume_io,         0 },
1998         [ P_outdate ]           = { &drbd_nl_outdate,           0 },
1999         [ P_get_config ]        = { &drbd_nl_get_config,
2000                                     sizeof(struct syncer_conf_tag_len_struct) +
2001                                     sizeof(struct disk_conf_tag_len_struct) +
2002                                     sizeof(struct net_conf_tag_len_struct) },
2003         [ P_get_state ]         = { &drbd_nl_get_state,
2004                                     sizeof(struct get_state_tag_len_struct) +
2005                                     sizeof(struct sync_progress_tag_len_struct) },
2006         [ P_get_uuids ]         = { &drbd_nl_get_uuids,
2007                                     sizeof(struct get_uuids_tag_len_struct) },
2008         [ P_get_timeout_flag ]  = { &drbd_nl_get_timeout_flag,
2009                                     sizeof(struct get_timeout_flag_tag_len_struct)},
2010         [ P_start_ov ]          = { &drbd_nl_start_ov,          0 },
2011         [ P_new_c_uuid ]        = { &drbd_nl_new_c_uuid,        0 },
2012 };
2013
2014 static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms *nsp)
2015 {
2016         struct drbd_nl_cfg_req *nlp = (struct drbd_nl_cfg_req *)req->data;
2017         struct cn_handler_struct *cm;
2018         struct cn_msg *cn_reply;
2019         struct drbd_nl_cfg_reply *reply;
2020         struct drbd_conf *mdev;
2021         int retcode, rr;
2022         int reply_size = sizeof(struct cn_msg)
2023                 + sizeof(struct drbd_nl_cfg_reply)
2024                 + sizeof(short int);
2025
2026         if (!try_module_get(THIS_MODULE)) {
2027                 printk(KERN_ERR "drbd: try_module_get() failed!\n");
2028                 return;
2029         }
2030
2031         if (!cap_raised(nsp->eff_cap, CAP_SYS_ADMIN)) {
2032                 retcode = ERR_PERM;
2033                 goto fail;
2034         }
2035
2036         mdev = ensure_mdev(nlp);
2037         if (!mdev) {
2038                 retcode = ERR_MINOR_INVALID;
2039                 goto fail;
2040         }
2041
2042         if (nlp->packet_type >= P_nl_after_last_packet) {
2043                 retcode = ERR_PACKET_NR;
2044                 goto fail;
2045         }
2046
2047         cm = cnd_table + nlp->packet_type;
2048
2049         /* This may happen if packet number is 0: */
2050         if (cm->function == NULL) {
2051                 retcode = ERR_PACKET_NR;
2052                 goto fail;
2053         }
2054
2055         reply_size += cm->reply_body_size;
2056
2057         /* allocation not in the IO path, cqueue thread context */
2058         cn_reply = kmalloc(reply_size, GFP_KERNEL);
2059         if (!cn_reply) {
2060                 retcode = ERR_NOMEM;
2061                 goto fail;
2062         }
2063         reply = (struct drbd_nl_cfg_reply *) cn_reply->data;
2064
2065         reply->packet_type =
2066                 cm->reply_body_size ? nlp->packet_type : P_nl_after_last_packet;
2067         reply->minor = nlp->drbd_minor;
2068         reply->ret_code = NO_ERROR; /* Might by modified by cm->function. */
2069         /* reply->tag_list; might be modified by cm->function. */
2070
2071         rr = cm->function(mdev, nlp, reply);
2072
2073         cn_reply->id = req->id;
2074         cn_reply->seq = req->seq;
2075         cn_reply->ack = req->ack  + 1;
2076         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) + rr;
2077         cn_reply->flags = 0;
2078
2079         rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_KERNEL);
2080         if (rr && rr != -ESRCH)
2081                 printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2082
2083         kfree(cn_reply);
2084         module_put(THIS_MODULE);
2085         return;
2086  fail:
2087         drbd_nl_send_reply(req, retcode);
2088         module_put(THIS_MODULE);
2089 }
2090
2091 static atomic_t drbd_nl_seq = ATOMIC_INIT(2); /* two. */
2092
2093 static unsigned short *
2094 __tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data,
2095         unsigned short len, int nul_terminated)
2096 {
2097         unsigned short l = tag_descriptions[tag_number(tag)].max_len;
2098         len = (len < l) ? len :  l;
2099         put_unaligned(tag, tl++);
2100         put_unaligned(len, tl++);
2101         memcpy(tl, data, len);
2102         tl = (unsigned short*)((char*)tl + len);
2103         if (nul_terminated)
2104                 *((char*)tl - 1) = 0;
2105         return tl;
2106 }
2107
2108 static unsigned short *
2109 tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data, int len)
2110 {
2111         return __tl_add_blob(tl, tag, data, len, 0);
2112 }
2113
2114 static unsigned short *
2115 tl_add_str(unsigned short *tl, enum drbd_tags tag, const char *str)
2116 {
2117         return __tl_add_blob(tl, tag, str, strlen(str)+1, 0);
2118 }
2119
2120 static unsigned short *
2121 tl_add_int(unsigned short *tl, enum drbd_tags tag, const void *val)
2122 {
2123         put_unaligned(tag, tl++);
2124         switch(tag_type(tag)) {
2125         case TT_INTEGER:
2126                 put_unaligned(sizeof(int), tl++);
2127                 put_unaligned(*(int *)val, (int *)tl);
2128                 tl = (unsigned short*)((char*)tl+sizeof(int));
2129                 break;
2130         case TT_INT64:
2131                 put_unaligned(sizeof(u64), tl++);
2132                 put_unaligned(*(u64 *)val, (u64 *)tl);
2133                 tl = (unsigned short*)((char*)tl+sizeof(u64));
2134                 break;
2135         default:
2136                 /* someone did something stupid. */
2137                 ;
2138         }
2139         return tl;
2140 }
2141
2142 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state state)
2143 {
2144         char buffer[sizeof(struct cn_msg)+
2145                     sizeof(struct drbd_nl_cfg_reply)+
2146                     sizeof(struct get_state_tag_len_struct)+
2147                     sizeof(short int)];
2148         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2149         struct drbd_nl_cfg_reply *reply =
2150                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2151         unsigned short *tl = reply->tag_list;
2152
2153         /* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2154
2155         tl = get_state_to_tags(mdev, (struct get_state *)&state, tl);
2156
2157         put_unaligned(TT_END, tl++); /* Close the tag list */
2158
2159         cn_reply->id.idx = CN_IDX_DRBD;
2160         cn_reply->id.val = CN_VAL_DRBD;
2161
2162         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2163         cn_reply->ack = 0; /* not used here. */
2164         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2165                 (int)((char *)tl - (char *)reply->tag_list);
2166         cn_reply->flags = 0;
2167
2168         reply->packet_type = P_get_state;
2169         reply->minor = mdev_to_minor(mdev);
2170         reply->ret_code = NO_ERROR;
2171
2172         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2173 }
2174
2175 void drbd_bcast_ev_helper(struct drbd_conf *mdev, char *helper_name)
2176 {
2177         char buffer[sizeof(struct cn_msg)+
2178                     sizeof(struct drbd_nl_cfg_reply)+
2179                     sizeof(struct call_helper_tag_len_struct)+
2180                     sizeof(short int)];
2181         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2182         struct drbd_nl_cfg_reply *reply =
2183                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2184         unsigned short *tl = reply->tag_list;
2185
2186         /* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2187
2188         tl = tl_add_str(tl, T_helper, helper_name);
2189         put_unaligned(TT_END, tl++); /* Close the tag list */
2190
2191         cn_reply->id.idx = CN_IDX_DRBD;
2192         cn_reply->id.val = CN_VAL_DRBD;
2193
2194         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2195         cn_reply->ack = 0; /* not used here. */
2196         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2197                 (int)((char *)tl - (char *)reply->tag_list);
2198         cn_reply->flags = 0;
2199
2200         reply->packet_type = P_call_helper;
2201         reply->minor = mdev_to_minor(mdev);
2202         reply->ret_code = NO_ERROR;
2203
2204         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2205 }
2206
2207 void drbd_bcast_ee(struct drbd_conf *mdev,
2208                 const char *reason, const int dgs,
2209                 const char* seen_hash, const char* calc_hash,
2210                 const struct drbd_epoch_entry* e)
2211 {
2212         struct cn_msg *cn_reply;
2213         struct drbd_nl_cfg_reply *reply;
2214         unsigned short *tl;
2215         struct page *page;
2216         unsigned len;
2217
2218         if (!e)
2219                 return;
2220         if (!reason || !reason[0])
2221                 return;
2222
2223         /* apparently we have to memcpy twice, first to prepare the data for the
2224          * struct cn_msg, then within cn_netlink_send from the cn_msg to the
2225          * netlink skb. */
2226         /* receiver thread context, which is not in the writeout path (of this node),
2227          * but may be in the writeout path of the _other_ node.
2228          * GFP_NOIO to avoid potential "distributed deadlock". */
2229         cn_reply = kmalloc(
2230                 sizeof(struct cn_msg)+
2231                 sizeof(struct drbd_nl_cfg_reply)+
2232                 sizeof(struct dump_ee_tag_len_struct)+
2233                 sizeof(short int),
2234                 GFP_NOIO);
2235
2236         if (!cn_reply) {
2237                 dev_err(DEV, "could not kmalloc buffer for drbd_bcast_ee, sector %llu, size %u\n",
2238                                 (unsigned long long)e->sector, e->size);
2239                 return;
2240         }
2241
2242         reply = (struct drbd_nl_cfg_reply*)cn_reply->data;
2243         tl = reply->tag_list;
2244
2245         tl = tl_add_str(tl, T_dump_ee_reason, reason);
2246         tl = tl_add_blob(tl, T_seen_digest, seen_hash, dgs);
2247         tl = tl_add_blob(tl, T_calc_digest, calc_hash, dgs);
2248         tl = tl_add_int(tl, T_ee_sector, &e->sector);
2249         tl = tl_add_int(tl, T_ee_block_id, &e->block_id);
2250
2251         put_unaligned(T_ee_data, tl++);
2252         put_unaligned(e->size, tl++);
2253
2254         len = e->size;
2255         page = e->pages;
2256         page_chain_for_each(page) {
2257                 void *d = kmap_atomic(page, KM_USER0);
2258                 unsigned l = min_t(unsigned, len, PAGE_SIZE);
2259                 memcpy(tl, d, l);
2260                 kunmap_atomic(d, KM_USER0);
2261                 tl = (unsigned short*)((char*)tl + l);
2262                 len -= l;
2263         }
2264         put_unaligned(TT_END, tl++); /* Close the tag list */
2265
2266         cn_reply->id.idx = CN_IDX_DRBD;
2267         cn_reply->id.val = CN_VAL_DRBD;
2268
2269         cn_reply->seq = atomic_add_return(1,&drbd_nl_seq);
2270         cn_reply->ack = 0; // not used here.
2271         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2272                 (int)((char*)tl - (char*)reply->tag_list);
2273         cn_reply->flags = 0;
2274
2275         reply->packet_type = P_dump_ee;
2276         reply->minor = mdev_to_minor(mdev);
2277         reply->ret_code = NO_ERROR;
2278
2279         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2280         kfree(cn_reply);
2281 }
2282
2283 void drbd_bcast_sync_progress(struct drbd_conf *mdev)
2284 {
2285         char buffer[sizeof(struct cn_msg)+
2286                     sizeof(struct drbd_nl_cfg_reply)+
2287                     sizeof(struct sync_progress_tag_len_struct)+
2288                     sizeof(short int)];
2289         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2290         struct drbd_nl_cfg_reply *reply =
2291                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2292         unsigned short *tl = reply->tag_list;
2293         unsigned long rs_left;
2294         unsigned int res;
2295
2296         /* no local ref, no bitmap, no syncer progress, no broadcast. */
2297         if (!get_ldev(mdev))
2298                 return;
2299         drbd_get_syncer_progress(mdev, &rs_left, &res);
2300         put_ldev(mdev);
2301
2302         tl = tl_add_int(tl, T_sync_progress, &res);
2303         put_unaligned(TT_END, tl++); /* Close the tag list */
2304
2305         cn_reply->id.idx = CN_IDX_DRBD;
2306         cn_reply->id.val = CN_VAL_DRBD;
2307
2308         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2309         cn_reply->ack = 0; /* not used here. */
2310         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2311                 (int)((char *)tl - (char *)reply->tag_list);
2312         cn_reply->flags = 0;
2313
2314         reply->packet_type = P_sync_progress;
2315         reply->minor = mdev_to_minor(mdev);
2316         reply->ret_code = NO_ERROR;
2317
2318         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2319 }
2320
2321 int __init drbd_nl_init(void)
2322 {
2323         static struct cb_id cn_id_drbd;
2324         int err, try=10;
2325
2326         cn_id_drbd.val = CN_VAL_DRBD;
2327         do {
2328                 cn_id_drbd.idx = cn_idx;
2329                 err = cn_add_callback(&cn_id_drbd, "cn_drbd", &drbd_connector_callback);
2330                 if (!err)
2331                         break;
2332                 cn_idx = (cn_idx + CN_IDX_STEP);
2333         } while (try--);
2334
2335         if (err) {
2336                 printk(KERN_ERR "drbd: cn_drbd failed to register\n");
2337                 return err;
2338         }
2339
2340         return 0;
2341 }
2342
2343 void drbd_nl_cleanup(void)
2344 {
2345         static struct cb_id cn_id_drbd;
2346
2347         cn_id_drbd.idx = cn_idx;
2348         cn_id_drbd.val = CN_VAL_DRBD;
2349
2350         cn_del_callback(&cn_id_drbd);
2351 }
2352
2353 void drbd_nl_send_reply(struct cn_msg *req, int ret_code)
2354 {
2355         char buffer[sizeof(struct cn_msg)+sizeof(struct drbd_nl_cfg_reply)];
2356         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2357         struct drbd_nl_cfg_reply *reply =
2358                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2359         int rr;
2360
2361         cn_reply->id = req->id;
2362
2363         cn_reply->seq = req->seq;
2364         cn_reply->ack = req->ack  + 1;
2365         cn_reply->len = sizeof(struct drbd_nl_cfg_reply);
2366         cn_reply->flags = 0;
2367
2368         reply->minor = ((struct drbd_nl_cfg_req *)req->data)->drbd_minor;
2369         reply->ret_code = ret_code;
2370
2371         rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2372         if (rr && rr != -ESRCH)
2373                 printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2374 }
2375