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_req.h"
  37 #include "drbd_wrappers.h"
  38 #include <asm/unaligned.h>
  39 #include <linux/drbd_tag_magic.h>
  40 #include <linux/drbd_limits.h>
  41 #include <linux/compiler.h>
  42 #include <linux/kthread.h>
  43
  44 static unsigned short *tl_add_blob(unsigned short *, enum drbd_tags, const void *, int);
  45 static unsigned short *tl_add_str(unsigned short *, enum drbd_tags, const char *);
  46 static unsigned short *tl_add_int(unsigned short *, enum drbd_tags, const void *);
  47
  48 /* see get_sb_bdev and bd_claim */
  49 static char *drbd_m_holder = "Hands off! this is DRBD's meta data device.";
  50
  51 /* Generate the tag_list to struct functions */
  52 #define NL_PACKET(name, number, fields) \
  53 static int name ## _from_tags(struct drbd_conf *mdev, \
  54         unsigned short *tags, struct name *arg) __attribute__ ((unused)); \
  55 static int name ## _from_tags(struct drbd_conf *mdev, \
  56         unsigned short *tags, struct name *arg) \
  57 { \
  58         int tag; \
  59         int dlen; \
  60         \
  61         while ((tag = get_unaligned(tags++)) != TT_END) {       \
  62                 dlen = get_unaligned(tags++);                   \
  63                 switch (tag_number(tag)) { \
  64                 fields \
  65                 default: \
  66                         if (tag & T_MANDATORY) { \
  67                                 dev_err(DEV, "Unknown tag: %d\n", tag_number(tag)); \
  68                                 return 0; \
  69                         } \
  70                 } \
  71                 tags = (unsigned short *)((char *)tags + dlen); \
  72         } \
  73         return 1; \
  74 }
  75 #define NL_INTEGER(pn, pr, member) \
  76         case pn: /* D_ASSERT( tag_type(tag) == TT_INTEGER ); */ \
  77                 arg->member = get_unaligned((int *)(tags));     \
  78                 break;
  79 #define NL_INT64(pn, pr, member) \
  80         case pn: /* D_ASSERT( tag_type(tag) == TT_INT64 ); */ \
  81                 arg->member = get_unaligned((u64 *)(tags));     \
  82                 break;
  83 #define NL_BIT(pn, pr, member) \
  84         case pn: /* D_ASSERT( tag_type(tag) == TT_BIT ); */ \
  85                 arg->member = *(char *)(tags) ? 1 : 0; \
  86                 break;
  87 #define NL_STRING(pn, pr, member, len) \
  88         case pn: /* D_ASSERT( tag_type(tag) == TT_STRING ); */ \
  89                 if (dlen > len) { \
  90                         dev_err(DEV, "arg too long: %s (%u wanted, max len: %u bytes)\n", \
  91                                 #member, dlen, (unsigned int)len); \
  92                         return 0; \
  93                 } \
  94                  arg->member ## _len = dlen; \
  95                  memcpy(arg->member, tags, min_t(size_t, dlen, len)); \
  96                  break;
  97 #include "linux/drbd_nl.h"
  98
  99 /* Generate the struct to tag_list functions */
 100 #define NL_PACKET(name, number, fields) \
 101 static unsigned short* \
 102 name ## _to_tags(struct drbd_conf *mdev, \
 103         struct name *arg, unsigned short *tags) __attribute__ ((unused)); \
 104 static unsigned short* \
 105 name ## _to_tags(struct drbd_conf *mdev, \
 106         struct name *arg, unsigned short *tags) \
 107 { \
 108         fields \
 109         return tags; \
 110 }
 111
 112 #define NL_INTEGER(pn, pr, member) \
 113         put_unaligned(pn | pr | TT_INTEGER, tags++);    \
 114         put_unaligned(sizeof(int), tags++);             \
 115         put_unaligned(arg->member, (int *)tags);        \
 116         tags = (unsigned short *)((char *)tags+sizeof(int));
 117 #define NL_INT64(pn, pr, member) \
 118         put_unaligned(pn | pr | TT_INT64, tags++);      \
 119         put_unaligned(sizeof(u64), tags++);             \
 120         put_unaligned(arg->member, (u64 *)tags);        \
 121         tags = (unsigned short *)((char *)tags+sizeof(u64));
 122 #define NL_BIT(pn, pr, member) \
 123         put_unaligned(pn | pr | TT_BIT, tags++);        \
 124         put_unaligned(sizeof(char), tags++);            \
 125         *(char *)tags = arg->member; \
 126         tags = (unsigned short *)((char *)tags+sizeof(char));
 127 #define NL_STRING(pn, pr, member, len) \
 128         put_unaligned(pn | pr | TT_STRING, tags++);     \
 129         put_unaligned(arg->member ## _len, tags++);     \
 130         memcpy(tags, arg->member, arg->member ## _len); \
 131         tags = (unsigned short *)((char *)tags + arg->member ## _len);
 132 #include "linux/drbd_nl.h"
 133
 134 void drbd_bcast_ev_helper(struct drbd_conf *mdev, char *helper_name);
 135 void drbd_nl_send_reply(struct cn_msg *, int);
 136
 137 int drbd_khelper(struct drbd_conf *mdev, char *cmd)
 138 {
 139         char *envp[] = { "HOME=/",
 140                         "TERM=linux",
 141                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
 142                         NULL, /* Will be set to address family */
 143                         NULL, /* Will be set to address */
 144                         NULL };
 145
 146         char mb[12], af[20], ad[60], *afs;
 147         char *argv[] = {usermode_helper, cmd, mb, NULL };
 148         int ret;
 149
 150         snprintf(mb, 12, "minor-%d", mdev_to_minor(mdev));
 151
 152         if (get_net_conf(mdev)) {
 153                 switch (((struct sockaddr *)mdev->net_conf->peer_addr)->sa_family) {
 154                 case AF_INET6:
 155                         afs = "ipv6";
 156                         snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI6",
 157                                  &((struct sockaddr_in6 *)mdev->net_conf->peer_addr)->sin6_addr);
 158                         break;
 159                 case AF_INET:
 160                         afs = "ipv4";
 161                         snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI4",
 162                                  &((struct sockaddr_in *)mdev->net_conf->peer_addr)->sin_addr);
 163                         break;
 164                 default:
 165                         afs = "ssocks";
 166                         snprintf(ad, 60, "DRBD_PEER_ADDRESS=%pI4",
 167                                  &((struct sockaddr_in *)mdev->net_conf->peer_addr)->sin_addr);
 168                 }
 169                 snprintf(af, 20, "DRBD_PEER_AF=%s", afs);
 170                 envp[3]=af;
 171                 envp[4]=ad;
 172                 put_net_conf(mdev);
 173         }
 174
 175         /* The helper may take some time.
 176          * write out any unsynced meta data changes now */
 177         drbd_md_sync(mdev);
 178
 179         dev_info(DEV, "helper command: %s %s %s\n", usermode_helper, cmd, mb);
 180
 181         drbd_bcast_ev_helper(mdev, cmd);
 182         ret = call_usermodehelper(usermode_helper, argv, envp, 1);
 183         if (ret)
 184                 dev_warn(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
 185                                 usermode_helper, cmd, mb,
 186                                 (ret >> 8) & 0xff, ret);
 187         else
 188                 dev_info(DEV, "helper command: %s %s %s exit code %u (0x%x)\n",
 189                                 usermode_helper, cmd, mb,
 190                                 (ret >> 8) & 0xff, ret);
 191
 192         if (ret < 0) /* Ignore any ERRNOs we got. */
 193                 ret = 0;
 194
 195         return ret;
 196 }
 197
 198 enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev)
 199 {
 200         char *ex_to_string;
 201         int r;
 202         enum drbd_disk_state nps;
 203         enum drbd_fencing_p fp;
 204
 205         D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
 206
 207         if (get_ldev_if_state(mdev, D_CONSISTENT)) {
 208                 fp = mdev->ldev->dc.fencing;
 209                 put_ldev(mdev);
 210         } else {
 211                 dev_warn(DEV, "Not fencing peer, I'm not even Consistent myself.\n");
 212                 nps = mdev->state.pdsk;
 213                 goto out;
 214         }
 215
 216         r = drbd_khelper(mdev, "fence-peer");
 217
 218         switch ((r>>8) & 0xff) {
 219         case 3: /* peer is inconsistent */
 220                 ex_to_string = "peer is inconsistent or worse";
 221                 nps = D_INCONSISTENT;
 222                 break;
 223         case 4: /* peer got outdated, or was already outdated */
 224                 ex_to_string = "peer was fenced";
 225                 nps = D_OUTDATED;
 226                 break;
 227         case 5: /* peer was down */
 228                 if (mdev->state.disk == D_UP_TO_DATE) {
 229                         /* we will(have) create(d) a new UUID anyways... */
 230                         ex_to_string = "peer is unreachable, assumed to be dead";
 231                         nps = D_OUTDATED;
 232                 } else {
 233                         ex_to_string = "peer unreachable, doing nothing since disk != UpToDate";
 234                         nps = mdev->state.pdsk;
 235                 }
 236                 break;
 237         case 6: /* Peer is primary, voluntarily outdate myself.
 238                  * This is useful when an unconnected R_SECONDARY is asked to
 239                  * become R_PRIMARY, but finds the other peer being active. */
 240                 ex_to_string = "peer is active";
 241                 dev_warn(DEV, "Peer is primary, outdating myself.\n");
 242                 nps = D_UNKNOWN;
 243                 _drbd_request_state(mdev, NS(disk, D_OUTDATED), CS_WAIT_COMPLETE);
 244                 break;
 245         case 7:
 246                 if (fp != FP_STONITH)
 247                         dev_err(DEV, "fence-peer() = 7 && fencing != Stonith !!!\n");
 248                 ex_to_string = "peer was stonithed";
 249                 nps = D_OUTDATED;
 250                 break;
 251         default:
 252                 /* The script is broken ... */
 253                 nps = D_UNKNOWN;
 254                 dev_err(DEV, "fence-peer helper broken, returned %d\n", (r>>8)&0xff);
 255                 return nps;
 256         }
 257
 258         dev_info(DEV, "fence-peer helper returned %d (%s)\n",
 259                         (r>>8) & 0xff, ex_to_string);
 260
 261 out:
 262         if (mdev->state.susp_fen && nps >= D_UNKNOWN) {
 263                 /* The handler was not successful... unfreeze here, the
 264                    state engine can not unfreeze... */
 265                 _drbd_request_state(mdev, NS(susp_fen, 0), CS_VERBOSE);
 266         }
 267
 268         return nps;
 269 }
 270
 271 static int _try_outdate_peer_async(void *data)
 272 {
 273         struct drbd_conf *mdev = (struct drbd_conf *)data;
 274         enum drbd_disk_state nps;
 275
 276         nps = drbd_try_outdate_peer(mdev);
 277         drbd_request_state(mdev, NS(pdsk, nps));
 278
 279         return 0;
 280 }
 281
 282 void drbd_try_outdate_peer_async(struct drbd_conf *mdev)
 283 {
 284         struct task_struct *opa;
 285
 286         opa = kthread_run(_try_outdate_peer_async, mdev, "drbd%d_a_helper", mdev_to_minor(mdev));
 287         if (IS_ERR(opa))
 288                 dev_err(DEV, "out of mem, failed to invoke fence-peer helper\n");
 289 }
 290
 291 int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, int force)
 292 {
 293         const int max_tries = 4;
 294         int r = 0;
 295         int try = 0;
 296         int forced = 0;
 297         union drbd_state mask, val;
 298         enum drbd_disk_state nps;
 299
 300         if (new_role == R_PRIMARY)
 301                 request_ping(mdev); /* Detect a dead peer ASAP */
 302
 303         mutex_lock(&mdev->state_mutex);
 304
 305         mask.i = 0; mask.role = R_MASK;
 306         val.i  = 0; val.role  = new_role;
 307
 308         while (try++ < max_tries) {
 309                 r = _drbd_request_state(mdev, mask, val, CS_WAIT_COMPLETE);
 310
 311                 /* in case we first succeeded to outdate,
 312                  * but now suddenly could establish a connection */
 313                 if (r == SS_CW_FAILED_BY_PEER && mask.pdsk != 0) {
 314                         val.pdsk = 0;
 315                         mask.pdsk = 0;
 316                         continue;
 317                 }
 318
 319                 if (r == SS_NO_UP_TO_DATE_DISK && force &&
 320                     (mdev->state.disk < D_UP_TO_DATE &&
 321                      mdev->state.disk >= D_INCONSISTENT)) {
 322                         mask.disk = D_MASK;
 323                         val.disk  = D_UP_TO_DATE;
 324                         forced = 1;
 325                         continue;
 326                 }
 327
 328                 if (r == SS_NO_UP_TO_DATE_DISK &&
 329                     mdev->state.disk == D_CONSISTENT && mask.pdsk == 0) {
 330                         D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
 331                         nps = drbd_try_outdate_peer(mdev);
 332
 333                         if (nps == D_OUTDATED || nps == D_INCONSISTENT) {
 334                                 val.disk = D_UP_TO_DATE;
 335                                 mask.disk = D_MASK;
 336                         }
 337
 338                         val.pdsk = nps;
 339                         mask.pdsk = D_MASK;
 340
 341                         continue;
 342                 }
 343
 344                 if (r == SS_NOTHING_TO_DO)
 345                         goto fail;
 346                 if (r == SS_PRIMARY_NOP && mask.pdsk == 0) {
 347                         nps = drbd_try_outdate_peer(mdev);
 348
 349                         if (force && nps > D_OUTDATED) {
 350                                 dev_warn(DEV, "Forced into split brain situation!\n");
 351                                 nps = D_OUTDATED;
 352                         }
 353
 354                         mask.pdsk = D_MASK;
 355                         val.pdsk  = nps;
 356
 357                         continue;
 358                 }
 359                 if (r == SS_TWO_PRIMARIES) {
 360                         /* Maybe the peer is detected as dead very soon...
 361                            retry at most once more in this case. */
 362                         __set_current_state(TASK_INTERRUPTIBLE);
 363                         schedule_timeout((mdev->net_conf->ping_timeo+1)*HZ/10);
 364                         if (try < max_tries)
 365                                 try = max_tries - 1;
 366                         continue;
 367                 }
 368                 if (r < SS_SUCCESS) {
 369                         r = _drbd_request_state(mdev, mask, val,
 370                                                 CS_VERBOSE + CS_WAIT_COMPLETE);
 371                         if (r < SS_SUCCESS)
 372                                 goto fail;
 373                 }
 374                 break;
 375         }
 376
 377         if (r < SS_SUCCESS)
 378                 goto fail;
 379
 380         if (forced)
 381                 dev_warn(DEV, "Forced to consider local data as UpToDate!\n");
 382
 383         /* Wait until nothing is on the fly :) */
 384         wait_event(mdev->misc_wait, atomic_read(&mdev->ap_pending_cnt) == 0);
 385
 386         if (new_role == R_SECONDARY) {
 387                 set_disk_ro(mdev->vdisk, TRUE);
 388                 if (get_ldev(mdev)) {
 389                         mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
 390                         put_ldev(mdev);
 391                 }
 392         } else {
 393                 if (get_net_conf(mdev)) {
 394                         mdev->net_conf->want_lose = 0;
 395                         put_net_conf(mdev);
 396                 }
 397                 set_disk_ro(mdev->vdisk, FALSE);
 398                 if (get_ldev(mdev)) {
 399                         if (((mdev->state.conn < C_CONNECTED ||
 400                                mdev->state.pdsk <= D_FAILED)
 401                               && mdev->ldev->md.uuid[UI_BITMAP] == 0) || forced)
 402                                 drbd_uuid_new_current(mdev);
 403
 404                         mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
 405                         put_ldev(mdev);
 406                 }
 407         }
 408
 409         if ((new_role == R_SECONDARY) && get_ldev(mdev)) {
 410                 drbd_al_to_on_disk_bm(mdev);
 411                 put_ldev(mdev);
 412         }
 413
 414         if (mdev->state.conn >= C_WF_REPORT_PARAMS) {
 415                 /* if this was forced, we should consider sync */
 416                 if (forced)
 417                         drbd_send_uuids(mdev);
 418                 drbd_send_state(mdev);
 419         }
 420
 421         drbd_md_sync(mdev);
 422
 423         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
 424  fail:
 425         mutex_unlock(&mdev->state_mutex);
 426         return r;
 427 }
 428
 429 static struct drbd_conf *ensure_mdev(int minor, int create)
 430 {
 431         struct drbd_conf *mdev;
 432
 433         if (minor >= minor_count)
 434                 return NULL;
 435
 436         mdev = minor_to_mdev(minor);
 437
 438         if (!mdev && create) {
 439                 struct gendisk *disk = NULL;
 440                 mdev = drbd_new_device(minor);
 441
 442                 spin_lock_irq(&drbd_pp_lock);
 443                 if (minor_table[minor] == NULL) {
 444                         minor_table[minor] = mdev;
 445                         disk = mdev->vdisk;
 446                         mdev = NULL;
 447                 } /* else: we lost the race */
 448                 spin_unlock_irq(&drbd_pp_lock);
 449
 450                 if (disk) /* we won the race above */
 451                         /* in case we ever add a drbd_delete_device(),
 452                          * don't forget the del_gendisk! */
 453                         add_disk(disk);
 454                 else /* we lost the race above */
 455                         drbd_free_mdev(mdev);
 456
 457                 mdev = minor_to_mdev(minor);
 458         }
 459
 460         return mdev;
 461 }
 462
 463 static int drbd_nl_primary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
 464                            struct drbd_nl_cfg_reply *reply)
 465 {
 466         struct primary primary_args;
 467
 468         memset(&primary_args, 0, sizeof(struct primary));
 469         if (!primary_from_tags(mdev, nlp->tag_list, &primary_args)) {
 470                 reply->ret_code = ERR_MANDATORY_TAG;
 471                 return 0;
 472         }
 473
 474         reply->ret_code =
 475                 drbd_set_role(mdev, R_PRIMARY, primary_args.primary_force);
 476
 477         return 0;
 478 }
 479
 480 static int drbd_nl_secondary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
 481                              struct drbd_nl_cfg_reply *reply)
 482 {
 483         reply->ret_code = drbd_set_role(mdev, R_SECONDARY, 0);
 484
 485         return 0;
 486 }
 487
 488 /* initializes the md.*_offset members, so we are able to find
 489  * the on disk meta data */
 490 static void drbd_md_set_sector_offsets(struct drbd_conf *mdev,
 491                                        struct drbd_backing_dev *bdev)
 492 {
 493         sector_t md_size_sect = 0;
 494         switch (bdev->dc.meta_dev_idx) {
 495         default:
 496                 /* v07 style fixed size indexed meta data */
 497                 bdev->md.md_size_sect = MD_RESERVED_SECT;
 498                 bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
 499                 bdev->md.al_offset = MD_AL_OFFSET;
 500                 bdev->md.bm_offset = MD_BM_OFFSET;
 501                 break;
 502         case DRBD_MD_INDEX_FLEX_EXT:
 503                 /* just occupy the full device; unit: sectors */
 504                 bdev->md.md_size_sect = drbd_get_capacity(bdev->md_bdev);
 505                 bdev->md.md_offset = 0;
 506                 bdev->md.al_offset = MD_AL_OFFSET;
 507                 bdev->md.bm_offset = MD_BM_OFFSET;
 508                 break;
 509         case DRBD_MD_INDEX_INTERNAL:
 510         case DRBD_MD_INDEX_FLEX_INT:
 511                 bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
 512                 /* al size is still fixed */
 513                 bdev->md.al_offset = -MD_AL_MAX_SIZE;
 514                 /* we need (slightly less than) ~ this much bitmap sectors: */
 515                 md_size_sect = drbd_get_capacity(bdev->backing_bdev);
 516                 md_size_sect = ALIGN(md_size_sect, BM_SECT_PER_EXT);
 517                 md_size_sect = BM_SECT_TO_EXT(md_size_sect);
 518                 md_size_sect = ALIGN(md_size_sect, 8);
 519
 520                 /* plus the "drbd meta data super block",
 521                  * and the activity log; */
 522                 md_size_sect += MD_BM_OFFSET;
 523
 524                 bdev->md.md_size_sect = md_size_sect;
 525                 /* bitmap offset is adjusted by 'super' block size */
 526                 bdev->md.bm_offset   = -md_size_sect + MD_AL_OFFSET;
 527                 break;
 528         }
 529 }
 530
 531 char *ppsize(char *buf, unsigned long long size)
 532 {
 533         /* Needs 9 bytes at max. */
 534         static char units[] = { 'K', 'M', 'G', 'T', 'P', 'E' };
 535         int base = 0;
 536         while (size >= 10000) {
 537                 /* shift + round */
 538                 size = (size >> 10) + !!(size & (1<<9));
 539                 base++;
 540         }
 541         sprintf(buf, "%lu %cB", (long)size, units[base]);
 542
 543         return buf;
 544 }
 545
 546 /* there is still a theoretical deadlock when called from receiver
 547  * on an D_INCONSISTENT R_PRIMARY:
 548  *  remote READ does inc_ap_bio, receiver would need to receive answer
 549  *  packet from remote to dec_ap_bio again.
 550  *  receiver receive_sizes(), comes here,
 551  *  waits for ap_bio_cnt == 0. -> deadlock.
 552  * but this cannot happen, actually, because:
 553  *  R_PRIMARY D_INCONSISTENT, and peer's disk is unreachable
 554  *  (not connected, or bad/no disk on peer):
 555  *  see drbd_fail_request_early, ap_bio_cnt is zero.
 556  *  R_PRIMARY D_INCONSISTENT, and C_SYNC_TARGET:
 557  *  peer may not initiate a resize.
 558  */
 559 void drbd_suspend_io(struct drbd_conf *mdev)
 560 {
 561         set_bit(SUSPEND_IO, &mdev->flags);
 562         if (is_susp(mdev->state))
 563                 return;
 564         wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
 565 }
 566
 567 void drbd_resume_io(struct drbd_conf *mdev)
 568 {
 569         clear_bit(SUSPEND_IO, &mdev->flags);
 570         wake_up(&mdev->misc_wait);
 571 }
 572
 573 /**
 574  * drbd_determine_dev_size() -  Sets the right device size obeying all constraints
 575  * @mdev:       DRBD device.
 576  *
 577  * Returns 0 on success, negative return values indicate errors.
 578  * You should call drbd_md_sync() after calling this function.
 579  */
 580 enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *mdev, enum dds_flags flags) __must_hold(local)
 581 {
 582         sector_t prev_first_sect, prev_size; /* previous meta location */
 583         sector_t la_size;
 584         sector_t size;
 585         char ppb[10];
 586
 587         int md_moved, la_size_changed;
 588         enum determine_dev_size rv = unchanged;
 589
 590         /* race:
 591          * application request passes inc_ap_bio,
 592          * but then cannot get an AL-reference.
 593          * this function later may wait on ap_bio_cnt == 0. -> deadlock.
 594          *
 595          * to avoid that:
 596          * Suspend IO right here.
 597          * still lock the act_log to not trigger ASSERTs there.
 598          */
 599         drbd_suspend_io(mdev);
 600
 601         /* no wait necessary anymore, actually we could assert that */
 602         wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
 603
 604         prev_first_sect = drbd_md_first_sector(mdev->ldev);
 605         prev_size = mdev->ldev->md.md_size_sect;
 606         la_size = mdev->ldev->md.la_size_sect;
 607
 608         /* TODO: should only be some assert here, not (re)init... */
 609         drbd_md_set_sector_offsets(mdev, mdev->ldev);
 610
 611         size = drbd_new_dev_size(mdev, mdev->ldev, flags & DDSF_FORCED);
 612
 613         if (drbd_get_capacity(mdev->this_bdev) != size ||
 614             drbd_bm_capacity(mdev) != size) {
 615                 int err;
 616                 err = drbd_bm_resize(mdev, size, !(flags & DDSF_NO_RESYNC));
 617                 if (unlikely(err)) {
 618                         /* currently there is only one error: ENOMEM! */
 619                         size = drbd_bm_capacity(mdev)>>1;
 620                         if (size == 0) {
 621                                 dev_err(DEV, "OUT OF MEMORY! "
 622                                     "Could not allocate bitmap!\n");
 623                         } else {
 624                                 dev_err(DEV, "BM resizing failed. "
 625                                     "Leaving size unchanged at size = %lu KB\n",
 626                                     (unsigned long)size);
 627                         }
 628                         rv = dev_size_error;
 629                 }
 630                 /* racy, see comments above. */
 631                 drbd_set_my_capacity(mdev, size);
 632                 mdev->ldev->md.la_size_sect = size;
 633                 dev_info(DEV, "size = %s (%llu KB)\n", ppsize(ppb, size>>1),
 634                      (unsigned long long)size>>1);
 635         }
 636         if (rv == dev_size_error)
 637                 goto out;
 638
 639         la_size_changed = (la_size != mdev->ldev->md.la_size_sect);
 640
 641         md_moved = prev_first_sect != drbd_md_first_sector(mdev->ldev)
 642                 || prev_size       != mdev->ldev->md.md_size_sect;
 643
 644         if (la_size_changed || md_moved) {
 645                 drbd_al_shrink(mdev); /* All extents inactive. */
 646                 dev_info(DEV, "Writing the whole bitmap, %s\n",
 647                          la_size_changed && md_moved ? "size changed and md moved" :
 648                          la_size_changed ? "size changed" : "md moved");
 649                 rv = drbd_bitmap_io(mdev, &drbd_bm_write, "size changed"); /* does drbd_resume_io() ! */
 650                 drbd_md_mark_dirty(mdev);
 651         }
 652
 653         if (size > la_size)
 654                 rv = grew;
 655         if (size < la_size)
 656                 rv = shrunk;
 657 out:
 658         lc_unlock(mdev->act_log);
 659         wake_up(&mdev->al_wait);
 660         drbd_resume_io(mdev);
 661
 662         return rv;
 663 }
 664
 665 sector_t
 666 drbd_new_dev_size(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, int assume_peer_has_space)
 667 {
 668         sector_t p_size = mdev->p_size;   /* partner's disk size. */
 669         sector_t la_size = bdev->md.la_size_sect; /* last agreed size. */
 670         sector_t m_size; /* my size */
 671         sector_t u_size = bdev->dc.disk_size; /* size requested by user. */
 672         sector_t size = 0;
 673
 674         m_size = drbd_get_max_capacity(bdev);
 675
 676         if (mdev->state.conn < C_CONNECTED && assume_peer_has_space) {
 677                 dev_warn(DEV, "Resize while not connected was forced by the user!\n");
 678                 p_size = m_size;
 679         }
 680
 681         if (p_size && m_size) {
 682                 size = min_t(sector_t, p_size, m_size);
 683         } else {
 684                 if (la_size) {
 685                         size = la_size;
 686                         if (m_size && m_size < size)
 687                                 size = m_size;
 688                         if (p_size && p_size < size)
 689                                 size = p_size;
 690                 } else {
 691                         if (m_size)
 692                                 size = m_size;
 693                         if (p_size)
 694                                 size = p_size;
 695                 }
 696         }
 697
 698         if (size == 0)
 699                 dev_err(DEV, "Both nodes diskless!\n");
 700
 701         if (u_size) {
 702                 if (u_size > size)
 703                         dev_err(DEV, "Requested disk size is too big (%lu > %lu)\n",
 704                             (unsigned long)u_size>>1, (unsigned long)size>>1);
 705                 else
 706                         size = u_size;
 707         }
 708
 709         return size;
 710 }
 711
 712 /**
 713  * drbd_check_al_size() - Ensures that the AL is of the right size
 714  * @mdev:       DRBD device.
 715  *
 716  * Returns -EBUSY if current al lru is still used, -ENOMEM when allocation
 717  * failed, and 0 on success. You should call drbd_md_sync() after you called
 718  * this function.
 719  */
 720 static int drbd_check_al_size(struct drbd_conf *mdev)
 721 {
 722         struct lru_cache *n, *t;
 723         struct lc_element *e;
 724         unsigned int in_use;
 725         int i;
 726
 727         ERR_IF(mdev->sync_conf.al_extents < 7)
 728                 mdev->sync_conf.al_extents = 127;
 729
 730         if (mdev->act_log &&
 731             mdev->act_log->nr_elements == mdev->sync_conf.al_extents)
 732                 return 0;
 733
 734         in_use = 0;
 735         t = mdev->act_log;
 736         n = lc_create("act_log", drbd_al_ext_cache,
 737                 mdev->sync_conf.al_extents, sizeof(struct lc_element), 0);
 738
 739         if (n == NULL) {
 740                 dev_err(DEV, "Cannot allocate act_log lru!\n");
 741                 return -ENOMEM;
 742         }
 743         spin_lock_irq(&mdev->al_lock);
 744         if (t) {
 745                 for (i = 0; i < t->nr_elements; i++) {
 746                         e = lc_element_by_index(t, i);
 747                         if (e->refcnt)
 748                                 dev_err(DEV, "refcnt(%d)==%d\n",
 749                                     e->lc_number, e->refcnt);
 750                         in_use += e->refcnt;
 751                 }
 752         }
 753         if (!in_use)
 754                 mdev->act_log = n;
 755         spin_unlock_irq(&mdev->al_lock);
 756         if (in_use) {
 757                 dev_err(DEV, "Activity log still in use!\n");
 758                 lc_destroy(n);
 759                 return -EBUSY;
 760         } else {
 761                 if (t)
 762                         lc_destroy(t);
 763         }
 764         drbd_md_mark_dirty(mdev); /* we changed mdev->act_log->nr_elemens */
 765         return 0;
 766 }
 767
 768 void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_seg_s) __must_hold(local)
 769 {
 770         struct request_queue * const q = mdev->rq_queue;
 771         struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
 772         int max_segments = mdev->ldev->dc.max_bio_bvecs;
 773
 774         max_seg_s = min(queue_max_sectors(b) * queue_logical_block_size(b), max_seg_s);
 775
 776         blk_queue_max_hw_sectors(q, max_seg_s >> 9);
 777         blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
 778         blk_queue_max_segment_size(q, max_seg_s);
 779         blk_queue_logical_block_size(q, 512);
 780         blk_queue_segment_boundary(q, PAGE_SIZE-1);
 781         blk_stack_limits(&q->limits, &b->limits, 0);
 782
 783         dev_info(DEV, "max_segment_size ( = BIO size ) = %u\n", queue_max_segment_size(q));
 784
 785         if (q->backing_dev_info.ra_pages != b->backing_dev_info.ra_pages) {
 786                 dev_info(DEV, "Adjusting my ra_pages to backing device's (%lu -> %lu)\n",
 787                      q->backing_dev_info.ra_pages,
 788                      b->backing_dev_info.ra_pages);
 789                 q->backing_dev_info.ra_pages = b->backing_dev_info.ra_pages;
 790         }
 791 }
 792
 793 /* serialize deconfig (worker exiting, doing cleanup)
 794  * and reconfig (drbdsetup disk, drbdsetup net)
 795  *
 796  * Wait for a potentially exiting worker, then restart it,
 797  * or start a new one.  Flush any pending work, there may still be an
 798  * after_state_change queued.
 799  */
 800 static void drbd_reconfig_start(struct drbd_conf *mdev)
 801 {
 802         wait_event(mdev->state_wait, !test_and_set_bit(CONFIG_PENDING, &mdev->flags));
 803         wait_event(mdev->state_wait, !test_bit(DEVICE_DYING, &mdev->flags));
 804         drbd_thread_start(&mdev->worker);
 805         drbd_flush_workqueue(mdev);
 806 }
 807
 808 /* if still unconfigured, stops worker again.
 809  * if configured now, clears CONFIG_PENDING.
 810  * wakes potential waiters */
 811 static void drbd_reconfig_done(struct drbd_conf *mdev)
 812 {
 813         spin_lock_irq(&mdev->req_lock);
 814         if (mdev->state.disk == D_DISKLESS &&
 815             mdev->state.conn == C_STANDALONE &&
 816             mdev->state.role == R_SECONDARY) {
 817                 set_bit(DEVICE_DYING, &mdev->flags);
 818                 drbd_thread_stop_nowait(&mdev->worker);
 819         } else
 820                 clear_bit(CONFIG_PENDING, &mdev->flags);
 821         spin_unlock_irq(&mdev->req_lock);
 822         wake_up(&mdev->state_wait);
 823 }
 824
 825 /* Make sure IO is suspended before calling this function(). */
 826 static void drbd_suspend_al(struct drbd_conf *mdev)
 827 {
 828         int s = 0;
 829
 830         if (lc_try_lock(mdev->act_log)) {
 831                 drbd_al_shrink(mdev);
 832                 lc_unlock(mdev->act_log);
 833         } else {
 834                 dev_warn(DEV, "Failed to lock al in drbd_suspend_al()\n");
 835                 return;
 836         }
 837
 838         spin_lock_irq(&mdev->req_lock);
 839         if (mdev->state.conn < C_CONNECTED)
 840                 s = !test_and_set_bit(AL_SUSPENDED, &mdev->flags);
 841
 842         spin_unlock_irq(&mdev->req_lock);
 843
 844         if (s)
 845                 dev_info(DEV, "Suspended AL updates\n");
 846 }
 847
 848 /* does always return 0;
 849  * interesting return code is in reply->ret_code */
 850 static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
 851                              struct drbd_nl_cfg_reply *reply)
 852 {
 853         enum drbd_ret_codes retcode;
 854         enum determine_dev_size dd;
 855         sector_t max_possible_sectors;
 856         sector_t min_md_device_sectors;
 857         struct drbd_backing_dev *nbc = NULL; /* new_backing_conf */
 858         struct block_device *bdev;
 859         struct lru_cache *resync_lru = NULL;
 860         union drbd_state ns, os;
 861         unsigned int max_seg_s;
 862         int rv;
 863         int cp_discovered = 0;
 864         int logical_block_size;
 865
 866         drbd_reconfig_start(mdev);
 867
 868         /* if you want to reconfigure, please tear down first */
 869         if (mdev->state.disk > D_DISKLESS) {
 870                 retcode = ERR_DISK_CONFIGURED;
 871                 goto fail;
 872         }
 873         /* It may just now have detached because of IO error.  Make sure
 874          * drbd_ldev_destroy is done already, we may end up here very fast,
 875          * e.g. if someone calls attach from the on-io-error handler,
 876          * to realize a "hot spare" feature (not that I'd recommend that) */
 877         wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
 878
 879         /* allocation not in the IO path, cqueue thread context */
 880         nbc = kzalloc(sizeof(struct drbd_backing_dev), GFP_KERNEL);
 881         if (!nbc) {
 882                 retcode = ERR_NOMEM;
 883                 goto fail;
 884         }
 885
 886         nbc->dc.disk_size     = DRBD_DISK_SIZE_SECT_DEF;
 887         nbc->dc.on_io_error   = DRBD_ON_IO_ERROR_DEF;
 888         nbc->dc.fencing       = DRBD_FENCING_DEF;
 889         nbc->dc.max_bio_bvecs = DRBD_MAX_BIO_BVECS_DEF;
 890
 891         if (!disk_conf_from_tags(mdev, nlp->tag_list, &nbc->dc)) {
 892                 retcode = ERR_MANDATORY_TAG;
 893                 goto fail;
 894         }
 895
 896         if (nbc->dc.meta_dev_idx < DRBD_MD_INDEX_FLEX_INT) {
 897                 retcode = ERR_MD_IDX_INVALID;
 898                 goto fail;
 899         }
 900
 901         if (get_net_conf(mdev)) {
 902                 int prot = mdev->net_conf->wire_protocol;
 903                 put_net_conf(mdev);
 904                 if (nbc->dc.fencing == FP_STONITH && prot == DRBD_PROT_A) {
 905                         retcode = ERR_STONITH_AND_PROT_A;
 906                         goto fail;
 907                 }
 908         }
 909
 910         bdev = blkdev_get_by_path(nbc->dc.backing_dev,
 911                                   FMODE_READ | FMODE_WRITE | FMODE_EXCL, mdev);
 912         if (IS_ERR(bdev)) {
 913                 dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.backing_dev,
 914                         PTR_ERR(bdev));
 915                 retcode = ERR_OPEN_DISK;
 916                 goto fail;
 917         }
 918         nbc->backing_bdev = bdev;
 919
 920         /*
 921          * meta_dev_idx >= 0: external fixed size, possibly multiple
 922          * drbd sharing one meta device.  TODO in that case, paranoia
 923          * check that [md_bdev, meta_dev_idx] is not yet used by some
 924          * other drbd minor!  (if you use drbd.conf + drbdadm, that
 925          * should check it for you already; but if you don't, or
 926          * someone fooled it, we need to double check here)
 927          */
 928         bdev = blkdev_get_by_path(nbc->dc.meta_dev,
 929                                   FMODE_READ | FMODE_WRITE | FMODE_EXCL,
 930                                   (nbc->dc.meta_dev_idx < 0) ?
 931                                   (void *)mdev : (void *)drbd_m_holder);
 932         if (IS_ERR(bdev)) {
 933                 dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.meta_dev,
 934                         PTR_ERR(bdev));
 935                 retcode = ERR_OPEN_MD_DISK;
 936                 goto fail;
 937         }
 938         nbc->md_bdev = bdev;
 939
 940         if ((nbc->backing_bdev == nbc->md_bdev) !=
 941             (nbc->dc.meta_dev_idx == DRBD_MD_INDEX_INTERNAL ||
 942              nbc->dc.meta_dev_idx == DRBD_MD_INDEX_FLEX_INT)) {
 943                 retcode = ERR_MD_IDX_INVALID;
 944                 goto fail;
 945         }
 946
 947         resync_lru = lc_create("resync", drbd_bm_ext_cache,
 948                         61, sizeof(struct bm_extent),
 949                         offsetof(struct bm_extent, lce));
 950         if (!resync_lru) {
 951                 retcode = ERR_NOMEM;
 952                 goto fail;
 953         }
 954
 955         /* RT - for drbd_get_max_capacity() DRBD_MD_INDEX_FLEX_INT */
 956         drbd_md_set_sector_offsets(mdev, nbc);
 957
 958         if (drbd_get_max_capacity(nbc) < nbc->dc.disk_size) {
 959                 dev_err(DEV, "max capacity %llu smaller than disk size %llu\n",
 960                         (unsigned long long) drbd_get_max_capacity(nbc),
 961                         (unsigned long long) nbc->dc.disk_size);
 962                 retcode = ERR_DISK_TO_SMALL;
 963                 goto fail;
 964         }
 965
 966         if (nbc->dc.meta_dev_idx < 0) {
 967                 max_possible_sectors = DRBD_MAX_SECTORS_FLEX;
 968                 /* at least one MB, otherwise it does not make sense */
 969                 min_md_device_sectors = (2<<10);
 970         } else {
 971                 max_possible_sectors = DRBD_MAX_SECTORS;
 972                 min_md_device_sectors = MD_RESERVED_SECT * (nbc->dc.meta_dev_idx + 1);
 973         }
 974
 975         if (drbd_get_capacity(nbc->md_bdev) < min_md_device_sectors) {
 976                 retcode = ERR_MD_DISK_TO_SMALL;
 977                 dev_warn(DEV, "refusing attach: md-device too small, "
 978                      "at least %llu sectors needed for this meta-disk type\n",
 979                      (unsigned long long) min_md_device_sectors);
 980                 goto fail;
 981         }
 982
 983         /* Make sure the new disk is big enough
 984          * (we may currently be R_PRIMARY with no local disk...) */
 985         if (drbd_get_max_capacity(nbc) <
 986             drbd_get_capacity(mdev->this_bdev)) {
 987                 retcode = ERR_DISK_TO_SMALL;
 988                 goto fail;
 989         }
 990
 991         nbc->known_size = drbd_get_capacity(nbc->backing_bdev);
 992
 993         if (nbc->known_size > max_possible_sectors) {
 994                 dev_warn(DEV, "==> truncating very big lower level device "
 995                         "to currently maximum possible %llu sectors <==\n",
 996                         (unsigned long long) max_possible_sectors);
 997                 if (nbc->dc.meta_dev_idx >= 0)
 998                         dev_warn(DEV, "==>> using internal or flexible "
 999                                       "meta data may help <<==\n");
1000         }
1001
1002         drbd_suspend_io(mdev);
1003         /* also wait for the last barrier ack. */
1004         wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_pending_cnt) || is_susp(mdev->state));
1005         /* and for any other previously queued work */
1006         drbd_flush_workqueue(mdev);
1007
1008         retcode = _drbd_request_state(mdev, NS(disk, D_ATTACHING), CS_VERBOSE);
1009         drbd_resume_io(mdev);
1010         if (retcode < SS_SUCCESS)
1011                 goto fail;
1012
1013         if (!get_ldev_if_state(mdev, D_ATTACHING))
1014                 goto force_diskless;
1015
1016         drbd_md_set_sector_offsets(mdev, nbc);
1017
1018         /* allocate a second IO page if logical_block_size != 512 */
1019         logical_block_size = bdev_logical_block_size(nbc->md_bdev);
1020         if (logical_block_size == 0)
1021                 logical_block_size = MD_SECTOR_SIZE;
1022
1023         if (logical_block_size != MD_SECTOR_SIZE) {
1024                 if (!mdev->md_io_tmpp) {
1025                         struct page *page = alloc_page(GFP_NOIO);
1026                         if (!page)
1027                                 goto force_diskless_dec;
1028
1029                         dev_warn(DEV, "Meta data's bdev logical_block_size = %d != %d\n",
1030                              logical_block_size, MD_SECTOR_SIZE);
1031                         dev_warn(DEV, "Workaround engaged (has performance impact).\n");
1032
1033                         mdev->md_io_tmpp = page;
1034                 }
1035         }
1036
1037         if (!mdev->bitmap) {
1038                 if (drbd_bm_init(mdev)) {
1039                         retcode = ERR_NOMEM;
1040                         goto force_diskless_dec;
1041                 }
1042         }
1043
1044         retcode = drbd_md_read(mdev, nbc);
1045         if (retcode != NO_ERROR)
1046                 goto force_diskless_dec;
1047
1048         if (mdev->state.conn < C_CONNECTED &&
1049             mdev->state.role == R_PRIMARY &&
1050             (mdev->ed_uuid & ~((u64)1)) != (nbc->md.uuid[UI_CURRENT] & ~((u64)1))) {
1051                 dev_err(DEV, "Can only attach to data with current UUID=%016llX\n",
1052                     (unsigned long long)mdev->ed_uuid);
1053                 retcode = ERR_DATA_NOT_CURRENT;
1054                 goto force_diskless_dec;
1055         }
1056
1057         /* Since we are diskless, fix the activity log first... */
1058         if (drbd_check_al_size(mdev)) {
1059                 retcode = ERR_NOMEM;
1060                 goto force_diskless_dec;
1061         }
1062
1063         /* Prevent shrinking of consistent devices ! */
1064         if (drbd_md_test_flag(nbc, MDF_CONSISTENT) &&
1065             drbd_new_dev_size(mdev, nbc, 0) < nbc->md.la_size_sect) {
1066                 dev_warn(DEV, "refusing to truncate a consistent device\n");
1067                 retcode = ERR_DISK_TO_SMALL;
1068                 goto force_diskless_dec;
1069         }
1070
1071         if (!drbd_al_read_log(mdev, nbc)) {
1072                 retcode = ERR_IO_MD_DISK;
1073                 goto force_diskless_dec;
1074         }
1075
1076         /* Reset the "barriers don't work" bits here, then force meta data to
1077          * be written, to ensure we determine if barriers are supported. */
1078         if (nbc->dc.no_md_flush)
1079                 set_bit(MD_NO_FUA, &mdev->flags);
1080         else
1081                 clear_bit(MD_NO_FUA, &mdev->flags);
1082
1083         /* Point of no return reached.
1084          * Devices and memory are no longer released by error cleanup below.
1085          * now mdev takes over responsibility, and the state engine should
1086          * clean it up somewhere.  */
1087         D_ASSERT(mdev->ldev == NULL);
1088         mdev->ldev = nbc;
1089         mdev->resync = resync_lru;
1090         nbc = NULL;
1091         resync_lru = NULL;
1092
1093         mdev->write_ordering = WO_bdev_flush;
1094         drbd_bump_write_ordering(mdev, WO_bdev_flush);
1095
1096         if (drbd_md_test_flag(mdev->ldev, MDF_CRASHED_PRIMARY))
1097                 set_bit(CRASHED_PRIMARY, &mdev->flags);
1098         else
1099                 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1100
1101         if (drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
1102             !(mdev->state.role == R_PRIMARY && mdev->state.susp_nod)) {
1103                 set_bit(CRASHED_PRIMARY, &mdev->flags);
1104                 cp_discovered = 1;
1105         }
1106
1107         mdev->send_cnt = 0;
1108         mdev->recv_cnt = 0;
1109         mdev->read_cnt = 0;
1110         mdev->writ_cnt = 0;
1111
1112         max_seg_s = DRBD_MAX_SEGMENT_SIZE;
1113         if (mdev->state.conn == C_CONNECTED) {
1114                 /* We are Primary, Connected, and now attach a new local
1115                  * backing store. We must not increase the user visible maximum
1116                  * bio size on this device to something the peer may not be
1117                  * able to handle. */
1118                 if (mdev->agreed_pro_version < 94)
1119                         max_seg_s = queue_max_segment_size(mdev->rq_queue);
1120                 else if (mdev->agreed_pro_version == 94)
1121                         max_seg_s = DRBD_MAX_SIZE_H80_PACKET;
1122                 /* else: drbd 8.3.9 and later, stay with default */
1123         }
1124
1125         drbd_setup_queue_param(mdev, max_seg_s);
1126
1127         /* If I am currently not R_PRIMARY,
1128          * but meta data primary indicator is set,
1129          * I just now recover from a hard crash,
1130          * and have been R_PRIMARY before that crash.
1131          *
1132          * Now, if I had no connection before that crash
1133          * (have been degraded R_PRIMARY), chances are that
1134          * I won't find my peer now either.
1135          *
1136          * In that case, and _only_ in that case,
1137          * we use the degr-wfc-timeout instead of the default,
1138          * so we can automatically recover from a crash of a
1139          * degraded but active "cluster" after a certain timeout.
1140          */
1141         clear_bit(USE_DEGR_WFC_T, &mdev->flags);
1142         if (mdev->state.role != R_PRIMARY &&
1143              drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
1144             !drbd_md_test_flag(mdev->ldev, MDF_CONNECTED_IND))
1145                 set_bit(USE_DEGR_WFC_T, &mdev->flags);
1146
1147         dd = drbd_determin_dev_size(mdev, 0);
1148         if (dd == dev_size_error) {
1149                 retcode = ERR_NOMEM_BITMAP;
1150                 goto force_diskless_dec;
1151         } else if (dd == grew)
1152                 set_bit(RESYNC_AFTER_NEG, &mdev->flags);
1153
1154         if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
1155                 dev_info(DEV, "Assuming that all blocks are out of sync "
1156                      "(aka FullSync)\n");
1157                 if (drbd_bitmap_io(mdev, &drbd_bmio_set_n_write, "set_n_write from attaching")) {
1158                         retcode = ERR_IO_MD_DISK;
1159                         goto force_diskless_dec;
1160                 }
1161         } else {
1162                 if (drbd_bitmap_io(mdev, &drbd_bm_read, "read from attaching") < 0) {
1163                         retcode = ERR_IO_MD_DISK;
1164                         goto force_diskless_dec;
1165                 }
1166         }
1167
1168         if (cp_discovered) {
1169                 drbd_al_apply_to_bm(mdev);
1170                 drbd_al_to_on_disk_bm(mdev);
1171         }
1172
1173         if (_drbd_bm_total_weight(mdev) == drbd_bm_bits(mdev))
1174                 drbd_suspend_al(mdev); /* IO is still suspended here... */
1175
1176         spin_lock_irq(&mdev->req_lock);
1177         os = mdev->state;
1178         ns.i = os.i;
1179         /* If MDF_CONSISTENT is not set go into inconsistent state,
1180            otherwise investigate MDF_WasUpToDate...
1181            If MDF_WAS_UP_TO_DATE is not set go into D_OUTDATED disk state,
1182            otherwise into D_CONSISTENT state.
1183         */
1184         if (drbd_md_test_flag(mdev->ldev, MDF_CONSISTENT)) {
1185                 if (drbd_md_test_flag(mdev->ldev, MDF_WAS_UP_TO_DATE))
1186                         ns.disk = D_CONSISTENT;
1187                 else
1188                         ns.disk = D_OUTDATED;
1189         } else {
1190                 ns.disk = D_INCONSISTENT;
1191         }
1192
1193         if (drbd_md_test_flag(mdev->ldev, MDF_PEER_OUT_DATED))
1194                 ns.pdsk = D_OUTDATED;
1195
1196         if ( ns.disk == D_CONSISTENT &&
1197             (ns.pdsk == D_OUTDATED || mdev->ldev->dc.fencing == FP_DONT_CARE))
1198                 ns.disk = D_UP_TO_DATE;
1199
1200         /* All tests on MDF_PRIMARY_IND, MDF_CONNECTED_IND,
1201            MDF_CONSISTENT and MDF_WAS_UP_TO_DATE must happen before
1202            this point, because drbd_request_state() modifies these
1203            flags. */
1204
1205         /* In case we are C_CONNECTED postpone any decision on the new disk
1206            state after the negotiation phase. */
1207         if (mdev->state.conn == C_CONNECTED) {
1208                 mdev->new_state_tmp.i = ns.i;
1209                 ns.i = os.i;
1210                 ns.disk = D_NEGOTIATING;
1211
1212                 /* We expect to receive up-to-date UUIDs soon.
1213                    To avoid a race in receive_state, free p_uuid while
1214                    holding req_lock. I.e. atomic with the state change */
1215                 kfree(mdev->p_uuid);
1216                 mdev->p_uuid = NULL;
1217         }
1218
1219         rv = _drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
1220         ns = mdev->state;
1221         spin_unlock_irq(&mdev->req_lock);
1222
1223         if (rv < SS_SUCCESS)
1224                 goto force_diskless_dec;
1225
1226         if (mdev->state.role == R_PRIMARY)
1227                 mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
1228         else
1229                 mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
1230
1231         drbd_md_mark_dirty(mdev);
1232         drbd_md_sync(mdev);
1233
1234         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1235         put_ldev(mdev);
1236         reply->ret_code = retcode;
1237         drbd_reconfig_done(mdev);
1238         return 0;
1239
1240  force_diskless_dec:
1241         put_ldev(mdev);
1242  force_diskless:
1243         drbd_force_state(mdev, NS(disk, D_FAILED));
1244         drbd_md_sync(mdev);
1245  fail:
1246         if (nbc) {
1247                 if (nbc->backing_bdev)
1248                         blkdev_put(nbc->backing_bdev,
1249                                    FMODE_READ | FMODE_WRITE | FMODE_EXCL);
1250                 if (nbc->md_bdev)
1251                         blkdev_put(nbc->md_bdev,
1252                                    FMODE_READ | FMODE_WRITE | FMODE_EXCL);
1253                 kfree(nbc);
1254         }
1255         lc_destroy(resync_lru);
1256
1257         reply->ret_code = retcode;
1258         drbd_reconfig_done(mdev);
1259         return 0;
1260 }
1261
1262 /* Detaching the disk is a process in multiple stages.  First we need to lock
1263  * out application IO, in-flight IO, IO stuck in drbd_al_begin_io.
1264  * Then we transition to D_DISKLESS, and wait for put_ldev() to return all
1265  * internal references as well.
1266  * Only then we have finally detached. */
1267 static int drbd_nl_detach(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1268                           struct drbd_nl_cfg_reply *reply)
1269 {
1270         drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */
1271         reply->ret_code = drbd_request_state(mdev, NS(disk, D_DISKLESS));
1272         if (mdev->state.disk == D_DISKLESS)
1273                 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1274         drbd_resume_io(mdev);
1275         return 0;
1276 }
1277
1278 static int drbd_nl_net_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1279                             struct drbd_nl_cfg_reply *reply)
1280 {
1281         int i, ns;
1282         enum drbd_ret_codes retcode;
1283         struct net_conf *new_conf = NULL;
1284         struct crypto_hash *tfm = NULL;
1285         struct crypto_hash *integrity_w_tfm = NULL;
1286         struct crypto_hash *integrity_r_tfm = NULL;
1287         struct hlist_head *new_tl_hash = NULL;
1288         struct hlist_head *new_ee_hash = NULL;
1289         struct drbd_conf *odev;
1290         char hmac_name[CRYPTO_MAX_ALG_NAME];
1291         void *int_dig_out = NULL;
1292         void *int_dig_in = NULL;
1293         void *int_dig_vv = NULL;
1294         struct sockaddr *new_my_addr, *new_peer_addr, *taken_addr;
1295
1296         drbd_reconfig_start(mdev);
1297
1298         if (mdev->state.conn > C_STANDALONE) {
1299                 retcode = ERR_NET_CONFIGURED;
1300                 goto fail;
1301         }
1302
1303         /* allocation not in the IO path, cqueue thread context */
1304         new_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
1305         if (!new_conf) {
1306                 retcode = ERR_NOMEM;
1307                 goto fail;
1308         }
1309
1310         new_conf->timeout          = DRBD_TIMEOUT_DEF;
1311         new_conf->try_connect_int  = DRBD_CONNECT_INT_DEF;
1312         new_conf->ping_int         = DRBD_PING_INT_DEF;
1313         new_conf->max_epoch_size   = DRBD_MAX_EPOCH_SIZE_DEF;
1314         new_conf->max_buffers      = DRBD_MAX_BUFFERS_DEF;
1315         new_conf->unplug_watermark = DRBD_UNPLUG_WATERMARK_DEF;
1316         new_conf->sndbuf_size      = DRBD_SNDBUF_SIZE_DEF;
1317         new_conf->rcvbuf_size      = DRBD_RCVBUF_SIZE_DEF;
1318         new_conf->ko_count         = DRBD_KO_COUNT_DEF;
1319         new_conf->after_sb_0p      = DRBD_AFTER_SB_0P_DEF;
1320         new_conf->after_sb_1p      = DRBD_AFTER_SB_1P_DEF;
1321         new_conf->after_sb_2p      = DRBD_AFTER_SB_2P_DEF;
1322         new_conf->want_lose        = 0;
1323         new_conf->two_primaries    = 0;
1324         new_conf->wire_protocol    = DRBD_PROT_C;
1325         new_conf->ping_timeo       = DRBD_PING_TIMEO_DEF;
1326         new_conf->rr_conflict      = DRBD_RR_CONFLICT_DEF;
1327
1328         if (!net_conf_from_tags(mdev, nlp->tag_list, new_conf)) {
1329                 retcode = ERR_MANDATORY_TAG;
1330                 goto fail;
1331         }
1332
1333         if (new_conf->two_primaries
1334             && (new_conf->wire_protocol != DRBD_PROT_C)) {
1335                 retcode = ERR_NOT_PROTO_C;
1336                 goto fail;
1337         }
1338
1339         if (get_ldev(mdev)) {
1340                 enum drbd_fencing_p fp = mdev->ldev->dc.fencing;
1341                 put_ldev(mdev);
1342                 if (new_conf->wire_protocol == DRBD_PROT_A && fp == FP_STONITH) {
1343                         retcode = ERR_STONITH_AND_PROT_A;
1344                         goto fail;
1345                 }
1346         }
1347
1348         if (mdev->state.role == R_PRIMARY && new_conf->want_lose) {
1349                 retcode = ERR_DISCARD;
1350                 goto fail;
1351         }
1352
1353         retcode = NO_ERROR;
1354
1355         new_my_addr = (struct sockaddr *)&new_conf->my_addr;
1356         new_peer_addr = (struct sockaddr *)&new_conf->peer_addr;
1357         for (i = 0; i < minor_count; i++) {
1358                 odev = minor_to_mdev(i);
1359                 if (!odev || odev == mdev)
1360                         continue;
1361                 if (get_net_conf(odev)) {
1362                         taken_addr = (struct sockaddr *)&odev->net_conf->my_addr;
1363                         if (new_conf->my_addr_len == odev->net_conf->my_addr_len &&
1364                             !memcmp(new_my_addr, taken_addr, new_conf->my_addr_len))
1365                                 retcode = ERR_LOCAL_ADDR;
1366
1367                         taken_addr = (struct sockaddr *)&odev->net_conf->peer_addr;
1368                         if (new_conf->peer_addr_len == odev->net_conf->peer_addr_len &&
1369                             !memcmp(new_peer_addr, taken_addr, new_conf->peer_addr_len))
1370                                 retcode = ERR_PEER_ADDR;
1371
1372                         put_net_conf(odev);
1373                         if (retcode != NO_ERROR)
1374                                 goto fail;
1375                 }
1376         }
1377
1378         if (new_conf->cram_hmac_alg[0] != 0) {
1379                 snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",
1380                         new_conf->cram_hmac_alg);
1381                 tfm = crypto_alloc_hash(hmac_name, 0, CRYPTO_ALG_ASYNC);
1382                 if (IS_ERR(tfm)) {
1383                         tfm = NULL;
1384                         retcode = ERR_AUTH_ALG;
1385                         goto fail;
1386                 }
1387
1388                 if (!drbd_crypto_is_hash(crypto_hash_tfm(tfm))) {
1389                         retcode = ERR_AUTH_ALG_ND;
1390                         goto fail;
1391                 }
1392         }
1393
1394         if (new_conf->integrity_alg[0]) {
1395                 integrity_w_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1396                 if (IS_ERR(integrity_w_tfm)) {
1397                         integrity_w_tfm = NULL;
1398                         retcode=ERR_INTEGRITY_ALG;
1399                         goto fail;
1400                 }
1401
1402                 if (!drbd_crypto_is_hash(crypto_hash_tfm(integrity_w_tfm))) {
1403                         retcode=ERR_INTEGRITY_ALG_ND;
1404                         goto fail;
1405                 }
1406
1407                 integrity_r_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1408                 if (IS_ERR(integrity_r_tfm)) {
1409                         integrity_r_tfm = NULL;
1410                         retcode=ERR_INTEGRITY_ALG;
1411                         goto fail;
1412                 }
1413         }
1414
1415         ns = new_conf->max_epoch_size/8;
1416         if (mdev->tl_hash_s != ns) {
1417                 new_tl_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1418                 if (!new_tl_hash) {
1419                         retcode = ERR_NOMEM;
1420                         goto fail;
1421                 }
1422         }
1423
1424         ns = new_conf->max_buffers/8;
1425         if (new_conf->two_primaries && (mdev->ee_hash_s != ns)) {
1426                 new_ee_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1427                 if (!new_ee_hash) {
1428                         retcode = ERR_NOMEM;
1429                         goto fail;
1430                 }
1431         }
1432
1433         ((char *)new_conf->shared_secret)[SHARED_SECRET_MAX-1] = 0;
1434
1435         if (integrity_w_tfm) {
1436                 i = crypto_hash_digestsize(integrity_w_tfm);
1437                 int_dig_out = kmalloc(i, GFP_KERNEL);
1438                 if (!int_dig_out) {
1439                         retcode = ERR_NOMEM;
1440                         goto fail;
1441                 }
1442                 int_dig_in = kmalloc(i, GFP_KERNEL);
1443                 if (!int_dig_in) {
1444                         retcode = ERR_NOMEM;
1445                         goto fail;
1446                 }
1447                 int_dig_vv = kmalloc(i, GFP_KERNEL);
1448                 if (!int_dig_vv) {
1449                         retcode = ERR_NOMEM;
1450                         goto fail;
1451                 }
1452         }
1453
1454         if (!mdev->bitmap) {
1455                 if(drbd_bm_init(mdev)) {
1456                         retcode = ERR_NOMEM;
1457                         goto fail;
1458                 }
1459         }
1460
1461         drbd_flush_workqueue(mdev);
1462         spin_lock_irq(&mdev->req_lock);
1463         if (mdev->net_conf != NULL) {
1464                 retcode = ERR_NET_CONFIGURED;
1465                 spin_unlock_irq(&mdev->req_lock);
1466                 goto fail;
1467         }
1468         mdev->net_conf = new_conf;
1469
1470         mdev->send_cnt = 0;
1471         mdev->recv_cnt = 0;
1472
1473         if (new_tl_hash) {
1474                 kfree(mdev->tl_hash);
1475                 mdev->tl_hash_s = mdev->net_conf->max_epoch_size/8;
1476                 mdev->tl_hash = new_tl_hash;
1477         }
1478
1479         if (new_ee_hash) {
1480                 kfree(mdev->ee_hash);
1481                 mdev->ee_hash_s = mdev->net_conf->max_buffers/8;
1482                 mdev->ee_hash = new_ee_hash;
1483         }
1484
1485         crypto_free_hash(mdev->cram_hmac_tfm);
1486         mdev->cram_hmac_tfm = tfm;
1487
1488         crypto_free_hash(mdev->integrity_w_tfm);
1489         mdev->integrity_w_tfm = integrity_w_tfm;
1490
1491         crypto_free_hash(mdev->integrity_r_tfm);
1492         mdev->integrity_r_tfm = integrity_r_tfm;
1493
1494         kfree(mdev->int_dig_out);
1495         kfree(mdev->int_dig_in);
1496         kfree(mdev->int_dig_vv);
1497         mdev->int_dig_out=int_dig_out;
1498         mdev->int_dig_in=int_dig_in;
1499         mdev->int_dig_vv=int_dig_vv;
1500         retcode = _drbd_set_state(_NS(mdev, conn, C_UNCONNECTED), CS_VERBOSE, NULL);
1501         spin_unlock_irq(&mdev->req_lock);
1502
1503         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1504         reply->ret_code = retcode;
1505         drbd_reconfig_done(mdev);
1506         return 0;
1507
1508 fail:
1509         kfree(int_dig_out);
1510         kfree(int_dig_in);
1511         kfree(int_dig_vv);
1512         crypto_free_hash(tfm);
1513         crypto_free_hash(integrity_w_tfm);
1514         crypto_free_hash(integrity_r_tfm);
1515         kfree(new_tl_hash);
1516         kfree(new_ee_hash);
1517         kfree(new_conf);
1518
1519         reply->ret_code = retcode;
1520         drbd_reconfig_done(mdev);
1521         return 0;
1522 }
1523
1524 static int drbd_nl_disconnect(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1525                               struct drbd_nl_cfg_reply *reply)
1526 {
1527         int retcode;
1528
1529         retcode = _drbd_request_state(mdev, NS(conn, C_DISCONNECTING), CS_ORDERED);
1530
1531         if (retcode == SS_NOTHING_TO_DO)
1532                 goto done;
1533         else if (retcode == SS_ALREADY_STANDALONE)
1534                 goto done;
1535         else if (retcode == SS_PRIMARY_NOP) {
1536                 /* Our statche checking code wants to see the peer outdated. */
1537                 retcode = drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1538                                                       pdsk, D_OUTDATED));
1539         } else if (retcode == SS_CW_FAILED_BY_PEER) {
1540                 /* The peer probably wants to see us outdated. */
1541                 retcode = _drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1542                                                         disk, D_OUTDATED),
1543                                               CS_ORDERED);
1544                 if (retcode == SS_IS_DISKLESS || retcode == SS_LOWER_THAN_OUTDATED) {
1545                         drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
1546                         retcode = SS_SUCCESS;
1547                 }
1548         }
1549
1550         if (retcode < SS_SUCCESS)
1551                 goto fail;
1552
1553         if (wait_event_interruptible(mdev->state_wait,
1554                                      mdev->state.conn != C_DISCONNECTING)) {
1555                 /* Do not test for mdev->state.conn == C_STANDALONE, since
1556                    someone else might connect us in the mean time! */
1557                 retcode = ERR_INTR;
1558                 goto fail;
1559         }
1560
1561  done:
1562         retcode = NO_ERROR;
1563  fail:
1564         drbd_md_sync(mdev);
1565         reply->ret_code = retcode;
1566         return 0;
1567 }
1568
1569 void resync_after_online_grow(struct drbd_conf *mdev)
1570 {
1571         int iass; /* I am sync source */
1572
1573         dev_info(DEV, "Resync of new storage after online grow\n");
1574         if (mdev->state.role != mdev->state.peer)
1575                 iass = (mdev->state.role == R_PRIMARY);
1576         else
1577                 iass = test_bit(DISCARD_CONCURRENT, &mdev->flags);
1578
1579         if (iass)
1580                 drbd_start_resync(mdev, C_SYNC_SOURCE);
1581         else
1582                 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE + CS_SERIALIZE);
1583 }
1584
1585 static int drbd_nl_resize(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1586                           struct drbd_nl_cfg_reply *reply)
1587 {
1588         struct resize rs;
1589         int retcode = NO_ERROR;
1590         enum determine_dev_size dd;
1591         enum dds_flags ddsf;
1592
1593         memset(&rs, 0, sizeof(struct resize));
1594         if (!resize_from_tags(mdev, nlp->tag_list, &rs)) {
1595                 retcode = ERR_MANDATORY_TAG;
1596                 goto fail;
1597         }
1598
1599         if (mdev->state.conn > C_CONNECTED) {
1600                 retcode = ERR_RESIZE_RESYNC;
1601                 goto fail;
1602         }
1603
1604         if (mdev->state.role == R_SECONDARY &&
1605             mdev->state.peer == R_SECONDARY) {
1606                 retcode = ERR_NO_PRIMARY;
1607                 goto fail;
1608         }
1609
1610         if (!get_ldev(mdev)) {
1611                 retcode = ERR_NO_DISK;
1612                 goto fail;
1613         }
1614
1615         if (rs.no_resync && mdev->agreed_pro_version < 93) {
1616                 retcode = ERR_NEED_APV_93;
1617                 goto fail;
1618         }
1619
1620         if (mdev->ldev->known_size != drbd_get_capacity(mdev->ldev->backing_bdev))
1621                 mdev->ldev->known_size = drbd_get_capacity(mdev->ldev->backing_bdev);
1622
1623         mdev->ldev->dc.disk_size = (sector_t)rs.resize_size;
1624         ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
1625         dd = drbd_determin_dev_size(mdev, ddsf);
1626         drbd_md_sync(mdev);
1627         put_ldev(mdev);
1628         if (dd == dev_size_error) {
1629                 retcode = ERR_NOMEM_BITMAP;
1630                 goto fail;
1631         }
1632
1633         if (mdev->state.conn == C_CONNECTED) {
1634                 if (dd == grew)
1635                         set_bit(RESIZE_PENDING, &mdev->flags);
1636
1637                 drbd_send_uuids(mdev);
1638                 drbd_send_sizes(mdev, 1, ddsf);
1639         }
1640
1641  fail:
1642         reply->ret_code = retcode;
1643         return 0;
1644 }
1645
1646 static int drbd_nl_syncer_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1647                                struct drbd_nl_cfg_reply *reply)
1648 {
1649         int retcode = NO_ERROR;
1650         int err;
1651         int ovr; /* online verify running */
1652         int rsr; /* re-sync running */
1653         struct crypto_hash *verify_tfm = NULL;
1654         struct crypto_hash *csums_tfm = NULL;
1655         struct syncer_conf sc;
1656         cpumask_var_t new_cpu_mask;
1657         int *rs_plan_s = NULL;
1658         int fifo_size;
1659
1660         if (!zalloc_cpumask_var(&new_cpu_mask, GFP_KERNEL)) {
1661                 retcode = ERR_NOMEM;
1662                 goto fail;
1663         }
1664
1665         if (nlp->flags & DRBD_NL_SET_DEFAULTS) {
1666                 memset(&sc, 0, sizeof(struct syncer_conf));
1667                 sc.rate       = DRBD_RATE_DEF;
1668                 sc.after      = DRBD_AFTER_DEF;
1669                 sc.al_extents = DRBD_AL_EXTENTS_DEF;
1670                 sc.on_no_data  = DRBD_ON_NO_DATA_DEF;
1671                 sc.c_plan_ahead = DRBD_C_PLAN_AHEAD_DEF;
1672                 sc.c_delay_target = DRBD_C_DELAY_TARGET_DEF;
1673                 sc.c_fill_target = DRBD_C_FILL_TARGET_DEF;
1674                 sc.c_max_rate = DRBD_C_MAX_RATE_DEF;
1675                 sc.c_min_rate = DRBD_C_MIN_RATE_DEF;
1676         } else
1677                 memcpy(&sc, &mdev->sync_conf, sizeof(struct syncer_conf));
1678
1679         if (!syncer_conf_from_tags(mdev, nlp->tag_list, &sc)) {
1680                 retcode = ERR_MANDATORY_TAG;
1681                 goto fail;
1682         }
1683
1684         /* re-sync running */
1685         rsr = ( mdev->state.conn == C_SYNC_SOURCE ||
1686                 mdev->state.conn == C_SYNC_TARGET ||
1687                 mdev->state.conn == C_PAUSED_SYNC_S ||
1688                 mdev->state.conn == C_PAUSED_SYNC_T );
1689
1690         if (rsr && strcmp(sc.csums_alg, mdev->sync_conf.csums_alg)) {
1691                 retcode = ERR_CSUMS_RESYNC_RUNNING;
1692                 goto fail;
1693         }
1694
1695         if (!rsr && sc.csums_alg[0]) {
1696                 csums_tfm = crypto_alloc_hash(sc.csums_alg, 0, CRYPTO_ALG_ASYNC);
1697                 if (IS_ERR(csums_tfm)) {
1698                         csums_tfm = NULL;
1699                         retcode = ERR_CSUMS_ALG;
1700                         goto fail;
1701                 }
1702
1703                 if (!drbd_crypto_is_hash(crypto_hash_tfm(csums_tfm))) {
1704                         retcode = ERR_CSUMS_ALG_ND;
1705                         goto fail;
1706                 }
1707         }
1708
1709         /* online verify running */
1710         ovr = (mdev->state.conn == C_VERIFY_S || mdev->state.conn == C_VERIFY_T);
1711
1712         if (ovr) {
1713                 if (strcmp(sc.verify_alg, mdev->sync_conf.verify_alg)) {
1714                         retcode = ERR_VERIFY_RUNNING;
1715                         goto fail;
1716                 }
1717         }
1718
1719         if (!ovr && sc.verify_alg[0]) {
1720                 verify_tfm = crypto_alloc_hash(sc.verify_alg, 0, CRYPTO_ALG_ASYNC);
1721                 if (IS_ERR(verify_tfm)) {
1722                         verify_tfm = NULL;
1723                         retcode = ERR_VERIFY_ALG;
1724                         goto fail;
1725                 }
1726
1727                 if (!drbd_crypto_is_hash(crypto_hash_tfm(verify_tfm))) {
1728                         retcode = ERR_VERIFY_ALG_ND;
1729                         goto fail;
1730                 }
1731         }
1732
1733         /* silently ignore cpu mask on UP kernel */
1734         if (nr_cpu_ids > 1 && sc.cpu_mask[0] != 0) {
1735                 err = __bitmap_parse(sc.cpu_mask, 32, 0,
1736                                 cpumask_bits(new_cpu_mask), nr_cpu_ids);
1737                 if (err) {
1738                         dev_warn(DEV, "__bitmap_parse() failed with %d\n", err);
1739                         retcode = ERR_CPU_MASK_PARSE;
1740                         goto fail;
1741                 }
1742         }
1743
1744         ERR_IF (sc.rate < 1) sc.rate = 1;
1745         ERR_IF (sc.al_extents < 7) sc.al_extents = 127; /* arbitrary minimum */
1746 #define AL_MAX ((MD_AL_MAX_SIZE-1) * AL_EXTENTS_PT)
1747         if (sc.al_extents > AL_MAX) {
1748                 dev_err(DEV, "sc.al_extents > %d\n", AL_MAX);
1749                 sc.al_extents = AL_MAX;
1750         }
1751 #undef AL_MAX
1752
1753         /* to avoid spurious errors when configuring minors before configuring
1754          * the minors they depend on: if necessary, first create the minor we
1755          * depend on */
1756         if (sc.after >= 0)
1757                 ensure_mdev(sc.after, 1);
1758
1759         /* most sanity checks done, try to assign the new sync-after
1760          * dependency.  need to hold the global lock in there,
1761          * to avoid a race in the dependency loop check. */
1762         retcode = drbd_alter_sa(mdev, sc.after);
1763         if (retcode != NO_ERROR)
1764                 goto fail;
1765
1766         fifo_size = (sc.c_plan_ahead * 10 * SLEEP_TIME) / HZ;
1767         if (fifo_size != mdev->rs_plan_s.size && fifo_size > 0) {
1768                 rs_plan_s   = kzalloc(sizeof(int) * fifo_size, GFP_KERNEL);
1769                 if (!rs_plan_s) {
1770                         dev_err(DEV, "kmalloc of fifo_buffer failed");
1771                         retcode = ERR_NOMEM;
1772                         goto fail;
1773                 }
1774         }
1775
1776         /* ok, assign the rest of it as well.
1777          * lock against receive_SyncParam() */
1778         spin_lock(&mdev->peer_seq_lock);
1779         mdev->sync_conf = sc;
1780
1781         if (!rsr) {
1782                 crypto_free_hash(mdev->csums_tfm);
1783                 mdev->csums_tfm = csums_tfm;
1784                 csums_tfm = NULL;
1785         }
1786
1787         if (!ovr) {
1788                 crypto_free_hash(mdev->verify_tfm);
1789                 mdev->verify_tfm = verify_tfm;
1790                 verify_tfm = NULL;
1791         }
1792
1793         if (fifo_size != mdev->rs_plan_s.size) {
1794                 kfree(mdev->rs_plan_s.values);
1795                 mdev->rs_plan_s.values = rs_plan_s;
1796                 mdev->rs_plan_s.size   = fifo_size;
1797                 mdev->rs_planed = 0;
1798                 rs_plan_s = NULL;
1799         }
1800
1801         spin_unlock(&mdev->peer_seq_lock);
1802
1803         if (get_ldev(mdev)) {
1804                 wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
1805                 drbd_al_shrink(mdev);
1806                 err = drbd_check_al_size(mdev);
1807                 lc_unlock(mdev->act_log);
1808                 wake_up(&mdev->al_wait);
1809
1810                 put_ldev(mdev);
1811                 drbd_md_sync(mdev);
1812
1813                 if (err) {
1814                         retcode = ERR_NOMEM;
1815                         goto fail;
1816                 }
1817         }
1818
1819         if (mdev->state.conn >= C_CONNECTED)
1820                 drbd_send_sync_param(mdev, &sc);
1821
1822         if (!cpumask_equal(mdev->cpu_mask, new_cpu_mask)) {
1823                 cpumask_copy(mdev->cpu_mask, new_cpu_mask);
1824                 drbd_calc_cpu_mask(mdev);
1825                 mdev->receiver.reset_cpu_mask = 1;
1826                 mdev->asender.reset_cpu_mask = 1;
1827                 mdev->worker.reset_cpu_mask = 1;
1828         }
1829
1830         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1831 fail:
1832         kfree(rs_plan_s);
1833         free_cpumask_var(new_cpu_mask);
1834         crypto_free_hash(csums_tfm);
1835         crypto_free_hash(verify_tfm);
1836         reply->ret_code = retcode;
1837         return 0;
1838 }
1839
1840 static int drbd_nl_invalidate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1841                               struct drbd_nl_cfg_reply *reply)
1842 {
1843         int retcode;
1844
1845         retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T), CS_ORDERED);
1846
1847         if (retcode < SS_SUCCESS && retcode != SS_NEED_CONNECTION)
1848                 retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1849
1850         while (retcode == SS_NEED_CONNECTION) {
1851                 spin_lock_irq(&mdev->req_lock);
1852                 if (mdev->state.conn < C_CONNECTED)
1853                         retcode = _drbd_set_state(_NS(mdev, disk, D_INCONSISTENT), CS_VERBOSE, NULL);
1854                 spin_unlock_irq(&mdev->req_lock);
1855
1856                 if (retcode != SS_NEED_CONNECTION)
1857                         break;
1858
1859                 retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1860         }
1861
1862         reply->ret_code = retcode;
1863         return 0;
1864 }
1865
1866 static int drbd_bmio_set_susp_al(struct drbd_conf *mdev)
1867 {
1868         int rv;
1869
1870         rv = drbd_bmio_set_n_write(mdev);
1871         drbd_suspend_al(mdev);
1872         return rv;
1873 }
1874
1875 static int drbd_nl_invalidate_peer(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1876                                    struct drbd_nl_cfg_reply *reply)
1877 {
1878         int retcode;
1879
1880         retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S), CS_ORDERED);
1881
1882         if (retcode < SS_SUCCESS) {
1883                 if (retcode == SS_NEED_CONNECTION && mdev->state.role == R_PRIMARY) {
1884                         /* The peer will get a resync upon connect anyways. Just make that
1885                            into a full resync. */
1886                         retcode = drbd_request_state(mdev, NS(pdsk, D_INCONSISTENT));
1887                         if (retcode >= SS_SUCCESS) {
1888                                 /* open coded drbd_bitmap_io() */
1889                                 if (drbd_bitmap_io(mdev, &drbd_bmio_set_susp_al,
1890                                                    "set_n_write from invalidate_peer"))
1891                                         retcode = ERR_IO_MD_DISK;
1892                         }
1893                 } else
1894                         retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S));
1895         }
1896
1897         reply->ret_code = retcode;
1898         return 0;
1899 }
1900
1901 static int drbd_nl_pause_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1902                               struct drbd_nl_cfg_reply *reply)
1903 {
1904         int retcode = NO_ERROR;
1905
1906         if (drbd_request_state(mdev, NS(user_isp, 1)) == SS_NOTHING_TO_DO)
1907                 retcode = ERR_PAUSE_IS_SET;
1908
1909         reply->ret_code = retcode;
1910         return 0;
1911 }
1912
1913 static int drbd_nl_resume_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1914                                struct drbd_nl_cfg_reply *reply)
1915 {
1916         int retcode = NO_ERROR;
1917
1918         if (drbd_request_state(mdev, NS(user_isp, 0)) == SS_NOTHING_TO_DO)
1919                 retcode = ERR_PAUSE_IS_CLEAR;
1920
1921         reply->ret_code = retcode;
1922         return 0;
1923 }
1924
1925 static int drbd_nl_suspend_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1926                               struct drbd_nl_cfg_reply *reply)
1927 {
1928         reply->ret_code = drbd_request_state(mdev, NS(susp, 1));
1929
1930         return 0;
1931 }
1932
1933 static int drbd_nl_resume_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1934                              struct drbd_nl_cfg_reply *reply)
1935 {
1936         if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
1937                 drbd_uuid_new_current(mdev);
1938                 clear_bit(NEW_CUR_UUID, &mdev->flags);
1939         }
1940         drbd_suspend_io(mdev);
1941         reply->ret_code = drbd_request_state(mdev, NS3(susp, 0, susp_nod, 0, susp_fen, 0));
1942         if (reply->ret_code == SS_SUCCESS) {
1943                 if (mdev->state.conn < C_CONNECTED)
1944                         tl_clear(mdev);
1945                 if (mdev->state.disk == D_DISKLESS || mdev->state.disk == D_FAILED)
1946                         tl_restart(mdev, fail_frozen_disk_io);
1947         }
1948         drbd_resume_io(mdev);
1949
1950         return 0;
1951 }
1952
1953 static int drbd_nl_outdate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1954                            struct drbd_nl_cfg_reply *reply)
1955 {
1956         reply->ret_code = drbd_request_state(mdev, NS(disk, D_OUTDATED));
1957         return 0;
1958 }
1959
1960 static int drbd_nl_get_config(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1961                            struct drbd_nl_cfg_reply *reply)
1962 {
1963         unsigned short *tl;
1964
1965         tl = reply->tag_list;
1966
1967         if (get_ldev(mdev)) {
1968                 tl = disk_conf_to_tags(mdev, &mdev->ldev->dc, tl);
1969                 put_ldev(mdev);
1970         }
1971
1972         if (get_net_conf(mdev)) {
1973                 tl = net_conf_to_tags(mdev, mdev->net_conf, tl);
1974                 put_net_conf(mdev);
1975         }
1976         tl = syncer_conf_to_tags(mdev, &mdev->sync_conf, tl);
1977
1978         put_unaligned(TT_END, tl++); /* Close the tag list */
1979
1980         return (int)((char *)tl - (char *)reply->tag_list);
1981 }
1982
1983 static int drbd_nl_get_state(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1984                              struct drbd_nl_cfg_reply *reply)
1985 {
1986         unsigned short *tl = reply->tag_list;
1987         union drbd_state s = mdev->state;
1988         unsigned long rs_left;
1989         unsigned int res;
1990
1991         tl = get_state_to_tags(mdev, (struct get_state *)&s, tl);
1992
1993         /* no local ref, no bitmap, no syncer progress. */
1994         if (s.conn >= C_SYNC_SOURCE && s.conn <= C_PAUSED_SYNC_T) {
1995                 if (get_ldev(mdev)) {
1996                         drbd_get_syncer_progress(mdev, &rs_left, &res);
1997                         tl = tl_add_int(tl, T_sync_progress, &res);
1998                         put_ldev(mdev);
1999                 }
2000         }
2001         put_unaligned(TT_END, tl++); /* Close the tag list */
2002
2003         return (int)((char *)tl - (char *)reply->tag_list);
2004 }
2005
2006 static int drbd_nl_get_uuids(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2007                              struct drbd_nl_cfg_reply *reply)
2008 {
2009         unsigned short *tl;
2010
2011         tl = reply->tag_list;
2012
2013         if (get_ldev(mdev)) {
2014                 tl = tl_add_blob(tl, T_uuids, mdev->ldev->md.uuid, UI_SIZE*sizeof(u64));
2015                 tl = tl_add_int(tl, T_uuids_flags, &mdev->ldev->md.flags);
2016                 put_ldev(mdev);
2017         }
2018         put_unaligned(TT_END, tl++); /* Close the tag list */
2019
2020         return (int)((char *)tl - (char *)reply->tag_list);
2021 }
2022
2023 /**
2024  * drbd_nl_get_timeout_flag() - Used by drbdsetup to find out which timeout value to use
2025  * @mdev:       DRBD device.
2026  * @nlp:        Netlink/connector packet from drbdsetup
2027  * @reply:      Reply packet for drbdsetup
2028  */
2029 static int drbd_nl_get_timeout_flag(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2030                                     struct drbd_nl_cfg_reply *reply)
2031 {
2032         unsigned short *tl;
2033         char rv;
2034
2035         tl = reply->tag_list;
2036
2037         rv = mdev->state.pdsk == D_OUTDATED        ? UT_PEER_OUTDATED :
2038           test_bit(USE_DEGR_WFC_T, &mdev->flags) ? UT_DEGRADED : UT_DEFAULT;
2039
2040         tl = tl_add_blob(tl, T_use_degraded, &rv, sizeof(rv));
2041         put_unaligned(TT_END, tl++); /* Close the tag list */
2042
2043         return (int)((char *)tl - (char *)reply->tag_list);
2044 }
2045
2046 static int drbd_nl_start_ov(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2047                                     struct drbd_nl_cfg_reply *reply)
2048 {
2049         /* default to resume from last known position, if possible */
2050         struct start_ov args =
2051                 { .start_sector = mdev->ov_start_sector };
2052
2053         if (!start_ov_from_tags(mdev, nlp->tag_list, &args)) {
2054                 reply->ret_code = ERR_MANDATORY_TAG;
2055                 return 0;
2056         }
2057         /* w_make_ov_request expects position to be aligned */
2058         mdev->ov_start_sector = args.start_sector & ~BM_SECT_PER_BIT;
2059         reply->ret_code = drbd_request_state(mdev,NS(conn,C_VERIFY_S));
2060         return 0;
2061 }
2062
2063
2064 static int drbd_nl_new_c_uuid(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2065                               struct drbd_nl_cfg_reply *reply)
2066 {
2067         int retcode = NO_ERROR;
2068         int skip_initial_sync = 0;
2069         int err;
2070
2071         struct new_c_uuid args;
2072
2073         memset(&args, 0, sizeof(struct new_c_uuid));
2074         if (!new_c_uuid_from_tags(mdev, nlp->tag_list, &args)) {
2075                 reply->ret_code = ERR_MANDATORY_TAG;
2076                 return 0;
2077         }
2078
2079         mutex_lock(&mdev->state_mutex); /* Protects us against serialized state changes. */
2080
2081         if (!get_ldev(mdev)) {
2082                 retcode = ERR_NO_DISK;
2083                 goto out;
2084         }
2085
2086         /* this is "skip initial sync", assume to be clean */
2087         if (mdev->state.conn == C_CONNECTED && mdev->agreed_pro_version >= 90 &&
2088             mdev->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED && args.clear_bm) {
2089                 dev_info(DEV, "Preparing to skip initial sync\n");
2090                 skip_initial_sync = 1;
2091         } else if (mdev->state.conn != C_STANDALONE) {
2092                 retcode = ERR_CONNECTED;
2093                 goto out_dec;
2094         }
2095
2096         drbd_uuid_set(mdev, UI_BITMAP, 0); /* Rotate UI_BITMAP to History 1, etc... */
2097         drbd_uuid_new_current(mdev); /* New current, previous to UI_BITMAP */
2098
2099         if (args.clear_bm) {
2100                 err = drbd_bitmap_io(mdev, &drbd_bmio_clear_n_write, "clear_n_write from new_c_uuid");
2101                 if (err) {
2102                         dev_err(DEV, "Writing bitmap failed with %d\n",err);
2103                         retcode = ERR_IO_MD_DISK;
2104                 }
2105                 if (skip_initial_sync) {
2106                         drbd_send_uuids_skip_initial_sync(mdev);
2107                         _drbd_uuid_set(mdev, UI_BITMAP, 0);
2108                         spin_lock_irq(&mdev->req_lock);
2109                         _drbd_set_state(_NS2(mdev, disk, D_UP_TO_DATE, pdsk, D_UP_TO_DATE),
2110                                         CS_VERBOSE, NULL);
2111                         spin_unlock_irq(&mdev->req_lock);
2112                 }
2113         }
2114
2115         drbd_md_sync(mdev);
2116 out_dec:
2117         put_ldev(mdev);
2118 out:
2119         mutex_unlock(&mdev->state_mutex);
2120
2121         reply->ret_code = retcode;
2122         return 0;
2123 }
2124
2125 struct cn_handler_struct {
2126         int (*function)(struct drbd_conf *,
2127                          struct drbd_nl_cfg_req *,
2128                          struct drbd_nl_cfg_reply *);
2129         int reply_body_size;
2130 };
2131
2132 static struct cn_handler_struct cnd_table[] = {
2133         [ P_primary ]           = { &drbd_nl_primary,           0 },
2134         [ P_secondary ]         = { &drbd_nl_secondary,         0 },
2135         [ P_disk_conf ]         = { &drbd_nl_disk_conf,         0 },
2136         [ P_detach ]            = { &drbd_nl_detach,            0 },
2137         [ P_net_conf ]          = { &drbd_nl_net_conf,          0 },
2138         [ P_disconnect ]        = { &drbd_nl_disconnect,        0 },
2139         [ P_resize ]            = { &drbd_nl_resize,            0 },
2140         [ P_syncer_conf ]       = { &drbd_nl_syncer_conf,       0 },
2141         [ P_invalidate ]        = { &drbd_nl_invalidate,        0 },
2142         [ P_invalidate_peer ]   = { &drbd_nl_invalidate_peer,   0 },
2143         [ P_pause_sync ]        = { &drbd_nl_pause_sync,        0 },
2144         [ P_resume_sync ]       = { &drbd_nl_resume_sync,       0 },
2145         [ P_suspend_io ]        = { &drbd_nl_suspend_io,        0 },
2146         [ P_resume_io ]         = { &drbd_nl_resume_io,         0 },
2147         [ P_outdate ]           = { &drbd_nl_outdate,           0 },
2148         [ P_get_config ]        = { &drbd_nl_get_config,
2149                                     sizeof(struct syncer_conf_tag_len_struct) +
2150                                     sizeof(struct disk_conf_tag_len_struct) +
2151                                     sizeof(struct net_conf_tag_len_struct) },
2152         [ P_get_state ]         = { &drbd_nl_get_state,
2153                                     sizeof(struct get_state_tag_len_struct) +
2154                                     sizeof(struct sync_progress_tag_len_struct) },
2155         [ P_get_uuids ]         = { &drbd_nl_get_uuids,
2156                                     sizeof(struct get_uuids_tag_len_struct) },
2157         [ P_get_timeout_flag ]  = { &drbd_nl_get_timeout_flag,
2158                                     sizeof(struct get_timeout_flag_tag_len_struct)},
2159         [ P_start_ov ]          = { &drbd_nl_start_ov,          0 },
2160         [ P_new_c_uuid ]        = { &drbd_nl_new_c_uuid,        0 },
2161 };
2162
2163 static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms *nsp)
2164 {
2165         struct drbd_nl_cfg_req *nlp = (struct drbd_nl_cfg_req *)req->data;
2166         struct cn_handler_struct *cm;
2167         struct cn_msg *cn_reply;
2168         struct drbd_nl_cfg_reply *reply;
2169         struct drbd_conf *mdev;
2170         int retcode, rr;
2171         int reply_size = sizeof(struct cn_msg)
2172                 + sizeof(struct drbd_nl_cfg_reply)
2173                 + sizeof(short int);
2174
2175         if (!try_module_get(THIS_MODULE)) {
2176                 printk(KERN_ERR "drbd: try_module_get() failed!\n");
2177                 return;
2178         }
2179
2180         if (!cap_raised(nsp->eff_cap, CAP_SYS_ADMIN)) {
2181                 retcode = ERR_PERM;
2182                 goto fail;
2183         }
2184
2185         mdev = ensure_mdev(nlp->drbd_minor,
2186                         (nlp->flags & DRBD_NL_CREATE_DEVICE));
2187         if (!mdev) {
2188                 retcode = ERR_MINOR_INVALID;
2189                 goto fail;
2190         }
2191
2192         if (nlp->packet_type >= P_nl_after_last_packet) {
2193                 retcode = ERR_PACKET_NR;
2194                 goto fail;
2195         }
2196
2197         cm = cnd_table + nlp->packet_type;
2198
2199         /* This may happen if packet number is 0: */
2200         if (cm->function == NULL) {
2201                 retcode = ERR_PACKET_NR;
2202                 goto fail;
2203         }
2204
2205         reply_size += cm->reply_body_size;
2206
2207         /* allocation not in the IO path, cqueue thread context */
2208         cn_reply = kmalloc(reply_size, GFP_KERNEL);
2209         if (!cn_reply) {
2210                 retcode = ERR_NOMEM;
2211                 goto fail;
2212         }
2213         reply = (struct drbd_nl_cfg_reply *) cn_reply->data;
2214
2215         reply->packet_type =
2216                 cm->reply_body_size ? nlp->packet_type : P_nl_after_last_packet;
2217         reply->minor = nlp->drbd_minor;
2218         reply->ret_code = NO_ERROR; /* Might by modified by cm->function. */
2219         /* reply->tag_list; might be modified by cm->function. */
2220
2221         rr = cm->function(mdev, nlp, reply);
2222
2223         cn_reply->id = req->id;
2224         cn_reply->seq = req->seq;
2225         cn_reply->ack = req->ack  + 1;
2226         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) + rr;
2227         cn_reply->flags = 0;
2228
2229         rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_KERNEL);
2230         if (rr && rr != -ESRCH)
2231                 printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2232
2233         kfree(cn_reply);
2234         module_put(THIS_MODULE);
2235         return;
2236  fail:
2237         drbd_nl_send_reply(req, retcode);
2238         module_put(THIS_MODULE);
2239 }
2240
2241 static atomic_t drbd_nl_seq = ATOMIC_INIT(2); /* two. */
2242
2243 static unsigned short *
2244 __tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data,
2245         unsigned short len, int nul_terminated)
2246 {
2247         unsigned short l = tag_descriptions[tag_number(tag)].max_len;
2248         len = (len < l) ? len :  l;
2249         put_unaligned(tag, tl++);
2250         put_unaligned(len, tl++);
2251         memcpy(tl, data, len);
2252         tl = (unsigned short*)((char*)tl + len);
2253         if (nul_terminated)
2254                 *((char*)tl - 1) = 0;
2255         return tl;
2256 }
2257
2258 static unsigned short *
2259 tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data, int len)
2260 {
2261         return __tl_add_blob(tl, tag, data, len, 0);
2262 }
2263
2264 static unsigned short *
2265 tl_add_str(unsigned short *tl, enum drbd_tags tag, const char *str)
2266 {
2267         return __tl_add_blob(tl, tag, str, strlen(str)+1, 0);
2268 }
2269
2270 static unsigned short *
2271 tl_add_int(unsigned short *tl, enum drbd_tags tag, const void *val)
2272 {
2273         put_unaligned(tag, tl++);
2274         switch(tag_type(tag)) {
2275         case TT_INTEGER:
2276                 put_unaligned(sizeof(int), tl++);
2277                 put_unaligned(*(int *)val, (int *)tl);
2278                 tl = (unsigned short*)((char*)tl+sizeof(int));
2279                 break;
2280         case TT_INT64:
2281                 put_unaligned(sizeof(u64), tl++);
2282                 put_unaligned(*(u64 *)val, (u64 *)tl);
2283                 tl = (unsigned short*)((char*)tl+sizeof(u64));
2284                 break;
2285         default:
2286                 /* someone did something stupid. */
2287                 ;
2288         }
2289         return tl;
2290 }
2291
2292 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state state)
2293 {
2294         char buffer[sizeof(struct cn_msg)+
2295                     sizeof(struct drbd_nl_cfg_reply)+
2296                     sizeof(struct get_state_tag_len_struct)+
2297                     sizeof(short int)];
2298         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2299         struct drbd_nl_cfg_reply *reply =
2300                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2301         unsigned short *tl = reply->tag_list;
2302
2303         /* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2304
2305         tl = get_state_to_tags(mdev, (struct get_state *)&state, tl);
2306
2307         put_unaligned(TT_END, tl++); /* Close the tag list */
2308
2309         cn_reply->id.idx = CN_IDX_DRBD;
2310         cn_reply->id.val = CN_VAL_DRBD;
2311
2312         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2313         cn_reply->ack = 0; /* not used here. */
2314         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2315                 (int)((char *)tl - (char *)reply->tag_list);
2316         cn_reply->flags = 0;
2317
2318         reply->packet_type = P_get_state;
2319         reply->minor = mdev_to_minor(mdev);
2320         reply->ret_code = NO_ERROR;
2321
2322         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2323 }
2324
2325 void drbd_bcast_ev_helper(struct drbd_conf *mdev, char *helper_name)
2326 {
2327         char buffer[sizeof(struct cn_msg)+
2328                     sizeof(struct drbd_nl_cfg_reply)+
2329                     sizeof(struct call_helper_tag_len_struct)+
2330                     sizeof(short int)];
2331         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2332         struct drbd_nl_cfg_reply *reply =
2333                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2334         unsigned short *tl = reply->tag_list;
2335
2336         /* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2337
2338         tl = tl_add_str(tl, T_helper, helper_name);
2339         put_unaligned(TT_END, tl++); /* Close the tag list */
2340
2341         cn_reply->id.idx = CN_IDX_DRBD;
2342         cn_reply->id.val = CN_VAL_DRBD;
2343
2344         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2345         cn_reply->ack = 0; /* not used here. */
2346         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2347                 (int)((char *)tl - (char *)reply->tag_list);
2348         cn_reply->flags = 0;
2349
2350         reply->packet_type = P_call_helper;
2351         reply->minor = mdev_to_minor(mdev);
2352         reply->ret_code = NO_ERROR;
2353
2354         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2355 }
2356
2357 void drbd_bcast_ee(struct drbd_conf *mdev,
2358                 const char *reason, const int dgs,
2359                 const char* seen_hash, const char* calc_hash,
2360                 const struct drbd_epoch_entry* e)
2361 {
2362         struct cn_msg *cn_reply;
2363         struct drbd_nl_cfg_reply *reply;
2364         unsigned short *tl;
2365         struct page *page;
2366         unsigned len;
2367
2368         if (!e)
2369                 return;
2370         if (!reason || !reason[0])
2371                 return;
2372
2373         /* apparently we have to memcpy twice, first to prepare the data for the
2374          * struct cn_msg, then within cn_netlink_send from the cn_msg to the
2375          * netlink skb. */
2376         /* receiver thread context, which is not in the writeout path (of this node),
2377          * but may be in the writeout path of the _other_ node.
2378          * GFP_NOIO to avoid potential "distributed deadlock". */
2379         cn_reply = kmalloc(
2380                 sizeof(struct cn_msg)+
2381                 sizeof(struct drbd_nl_cfg_reply)+
2382                 sizeof(struct dump_ee_tag_len_struct)+
2383                 sizeof(short int),
2384                 GFP_NOIO);
2385
2386         if (!cn_reply) {
2387                 dev_err(DEV, "could not kmalloc buffer for drbd_bcast_ee, sector %llu, size %u\n",
2388                                 (unsigned long long)e->sector, e->size);
2389                 return;
2390         }
2391
2392         reply = (struct drbd_nl_cfg_reply*)cn_reply->data;
2393         tl = reply->tag_list;
2394
2395         tl = tl_add_str(tl, T_dump_ee_reason, reason);
2396         tl = tl_add_blob(tl, T_seen_digest, seen_hash, dgs);
2397         tl = tl_add_blob(tl, T_calc_digest, calc_hash, dgs);
2398         tl = tl_add_int(tl, T_ee_sector, &e->sector);
2399         tl = tl_add_int(tl, T_ee_block_id, &e->block_id);
2400
2401         put_unaligned(T_ee_data, tl++);
2402         put_unaligned(e->size, tl++);
2403
2404         len = e->size;
2405         page = e->pages;
2406         page_chain_for_each(page) {
2407                 void *d = kmap_atomic(page, KM_USER0);
2408                 unsigned l = min_t(unsigned, len, PAGE_SIZE);
2409                 memcpy(tl, d, l);
2410                 kunmap_atomic(d, KM_USER0);
2411                 tl = (unsigned short*)((char*)tl + l);
2412                 len -= l;
2413         }
2414         put_unaligned(TT_END, tl++); /* Close the tag list */
2415
2416         cn_reply->id.idx = CN_IDX_DRBD;
2417         cn_reply->id.val = CN_VAL_DRBD;
2418
2419         cn_reply->seq = atomic_add_return(1,&drbd_nl_seq);
2420         cn_reply->ack = 0; // not used here.
2421         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2422                 (int)((char*)tl - (char*)reply->tag_list);
2423         cn_reply->flags = 0;
2424
2425         reply->packet_type = P_dump_ee;
2426         reply->minor = mdev_to_minor(mdev);
2427         reply->ret_code = NO_ERROR;
2428
2429         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2430         kfree(cn_reply);
2431 }
2432
2433 void drbd_bcast_sync_progress(struct drbd_conf *mdev)
2434 {
2435         char buffer[sizeof(struct cn_msg)+
2436                     sizeof(struct drbd_nl_cfg_reply)+
2437                     sizeof(struct sync_progress_tag_len_struct)+
2438                     sizeof(short int)];
2439         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2440         struct drbd_nl_cfg_reply *reply =
2441                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2442         unsigned short *tl = reply->tag_list;
2443         unsigned long rs_left;
2444         unsigned int res;
2445
2446         /* no local ref, no bitmap, no syncer progress, no broadcast. */
2447         if (!get_ldev(mdev))
2448                 return;
2449         drbd_get_syncer_progress(mdev, &rs_left, &res);
2450         put_ldev(mdev);
2451
2452         tl = tl_add_int(tl, T_sync_progress, &res);
2453         put_unaligned(TT_END, tl++); /* Close the tag list */
2454
2455         cn_reply->id.idx = CN_IDX_DRBD;
2456         cn_reply->id.val = CN_VAL_DRBD;
2457
2458         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2459         cn_reply->ack = 0; /* not used here. */
2460         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2461                 (int)((char *)tl - (char *)reply->tag_list);
2462         cn_reply->flags = 0;
2463
2464         reply->packet_type = P_sync_progress;
2465         reply->minor = mdev_to_minor(mdev);
2466         reply->ret_code = NO_ERROR;
2467
2468         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2469 }
2470
2471 int __init drbd_nl_init(void)
2472 {
2473         static struct cb_id cn_id_drbd;
2474         int err, try=10;
2475
2476         cn_id_drbd.val = CN_VAL_DRBD;
2477         do {
2478                 cn_id_drbd.idx = cn_idx;
2479                 err = cn_add_callback(&cn_id_drbd, "cn_drbd", &drbd_connector_callback);
2480                 if (!err)
2481                         break;
2482                 cn_idx = (cn_idx + CN_IDX_STEP);
2483         } while (try--);
2484
2485         if (err) {
2486                 printk(KERN_ERR "drbd: cn_drbd failed to register\n");
2487                 return err;
2488         }
2489
2490         return 0;
2491 }
2492
2493 void drbd_nl_cleanup(void)
2494 {
2495         static struct cb_id cn_id_drbd;
2496
2497         cn_id_drbd.idx = cn_idx;
2498         cn_id_drbd.val = CN_VAL_DRBD;
2499
2500         cn_del_callback(&cn_id_drbd);
2501 }
2502
2503 void drbd_nl_send_reply(struct cn_msg *req, int ret_code)
2504 {
2505         char buffer[sizeof(struct cn_msg)+sizeof(struct drbd_nl_cfg_reply)];
2506         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2507         struct drbd_nl_cfg_reply *reply =
2508                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2509         int rr;
2510
2511         cn_reply->id = req->id;
2512
2513         cn_reply->seq = req->seq;
2514         cn_reply->ack = req->ack  + 1;
2515         cn_reply->len = sizeof(struct drbd_nl_cfg_reply);
2516         cn_reply->flags = 0;
2517
2518         reply->minor = ((struct drbd_nl_cfg_req *)req->data)->drbd_minor;
2519         reply->ret_code = ret_code;
2520
2521         rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2522         if (rr && rr != -ESRCH)
2523                 printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2524 }
2525