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         union drbd_state ns;
 276
 277         nps = drbd_try_outdate_peer(mdev);
 278
 279         /* Not using
 280            drbd_request_state(mdev, NS(pdsk, nps));
 281            here, because we might were able to re-establish the connection
 282            in the meantime. This can only partially be solved in the state's
 283            engine is_valid_state() and is_valid_state_transition()
 284            functions.
 285
 286            nps can be D_INCONSISTENT, D_OUTDATED or D_UNKNOWN.
 287            pdsk == D_INCONSISTENT while conn >= C_CONNECTED is valid,
 288            therefore we have to have the pre state change check here.
 289         */
 290         spin_lock_irq(&mdev->req_lock);
 291         ns = mdev->state;
 292         if (ns.conn < C_WF_REPORT_PARAMS) {
 293                 ns.pdsk = nps;
 294                 _drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
 295         }
 296         spin_unlock_irq(&mdev->req_lock);
 297
 298         return 0;
 299 }
 300
 301 void drbd_try_outdate_peer_async(struct drbd_conf *mdev)
 302 {
 303         struct task_struct *opa;
 304
 305         opa = kthread_run(_try_outdate_peer_async, mdev, "drbd%d_a_helper", mdev_to_minor(mdev));
 306         if (IS_ERR(opa))
 307                 dev_err(DEV, "out of mem, failed to invoke fence-peer helper\n");
 308 }
 309
 310 enum drbd_state_rv
 311 drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, int force)
 312 {
 313         const int max_tries = 4;
 314         enum drbd_state_rv rv = SS_UNKNOWN_ERROR;
 315         int try = 0;
 316         int forced = 0;
 317         union drbd_state mask, val;
 318         enum drbd_disk_state nps;
 319
 320         if (new_role == R_PRIMARY)
 321                 request_ping(mdev); /* Detect a dead peer ASAP */
 322
 323         mutex_lock(&mdev->state_mutex);
 324
 325         mask.i = 0; mask.role = R_MASK;
 326         val.i  = 0; val.role  = new_role;
 327
 328         while (try++ < max_tries) {
 329                 rv = _drbd_request_state(mdev, mask, val, CS_WAIT_COMPLETE);
 330
 331                 /* in case we first succeeded to outdate,
 332                  * but now suddenly could establish a connection */
 333                 if (rv == SS_CW_FAILED_BY_PEER && mask.pdsk != 0) {
 334                         val.pdsk = 0;
 335                         mask.pdsk = 0;
 336                         continue;
 337                 }
 338
 339                 if (rv == SS_NO_UP_TO_DATE_DISK && force &&
 340                     (mdev->state.disk < D_UP_TO_DATE &&
 341                      mdev->state.disk >= D_INCONSISTENT)) {
 342                         mask.disk = D_MASK;
 343                         val.disk  = D_UP_TO_DATE;
 344                         forced = 1;
 345                         continue;
 346                 }
 347
 348                 if (rv == SS_NO_UP_TO_DATE_DISK &&
 349                     mdev->state.disk == D_CONSISTENT && mask.pdsk == 0) {
 350                         D_ASSERT(mdev->state.pdsk == D_UNKNOWN);
 351                         nps = drbd_try_outdate_peer(mdev);
 352
 353                         if (nps == D_OUTDATED || nps == D_INCONSISTENT) {
 354                                 val.disk = D_UP_TO_DATE;
 355                                 mask.disk = D_MASK;
 356                         }
 357
 358                         val.pdsk = nps;
 359                         mask.pdsk = D_MASK;
 360
 361                         continue;
 362                 }
 363
 364                 if (rv == SS_NOTHING_TO_DO)
 365                         goto fail;
 366                 if (rv == SS_PRIMARY_NOP && mask.pdsk == 0) {
 367                         nps = drbd_try_outdate_peer(mdev);
 368
 369                         if (force && nps > D_OUTDATED) {
 370                                 dev_warn(DEV, "Forced into split brain situation!\n");
 371                                 nps = D_OUTDATED;
 372                         }
 373
 374                         mask.pdsk = D_MASK;
 375                         val.pdsk  = nps;
 376
 377                         continue;
 378                 }
 379                 if (rv == SS_TWO_PRIMARIES) {
 380                         /* Maybe the peer is detected as dead very soon...
 381                            retry at most once more in this case. */
 382                         schedule_timeout_interruptible((mdev->net_conf->ping_timeo+1)*HZ/10);
 383                         if (try < max_tries)
 384                                 try = max_tries - 1;
 385                         continue;
 386                 }
 387                 if (rv < SS_SUCCESS) {
 388                         rv = _drbd_request_state(mdev, mask, val,
 389                                                 CS_VERBOSE + CS_WAIT_COMPLETE);
 390                         if (rv < SS_SUCCESS)
 391                                 goto fail;
 392                 }
 393                 break;
 394         }
 395
 396         if (rv < SS_SUCCESS)
 397                 goto fail;
 398
 399         if (forced)
 400                 dev_warn(DEV, "Forced to consider local data as UpToDate!\n");
 401
 402         /* Wait until nothing is on the fly :) */
 403         wait_event(mdev->misc_wait, atomic_read(&mdev->ap_pending_cnt) == 0);
 404
 405         if (new_role == R_SECONDARY) {
 406                 set_disk_ro(mdev->vdisk, true);
 407                 if (get_ldev(mdev)) {
 408                         mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
 409                         put_ldev(mdev);
 410                 }
 411         } else {
 412                 if (get_net_conf(mdev)) {
 413                         mdev->net_conf->want_lose = 0;
 414                         put_net_conf(mdev);
 415                 }
 416                 set_disk_ro(mdev->vdisk, false);
 417                 if (get_ldev(mdev)) {
 418                         if (((mdev->state.conn < C_CONNECTED ||
 419                                mdev->state.pdsk <= D_FAILED)
 420                               && mdev->ldev->md.uuid[UI_BITMAP] == 0) || forced)
 421                                 drbd_uuid_new_current(mdev);
 422
 423                         mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
 424                         put_ldev(mdev);
 425                 }
 426         }
 427
 428         /* writeout of activity log covered areas of the bitmap
 429          * to stable storage done in after state change already */
 430
 431         if (mdev->state.conn >= C_WF_REPORT_PARAMS) {
 432                 /* if this was forced, we should consider sync */
 433                 if (forced)
 434                         drbd_send_uuids(mdev);
 435                 drbd_send_state(mdev);
 436         }
 437
 438         drbd_md_sync(mdev);
 439
 440         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
 441  fail:
 442         mutex_unlock(&mdev->state_mutex);
 443         return rv;
 444 }
 445
 446 static struct drbd_conf *ensure_mdev(int minor, int create)
 447 {
 448         struct drbd_conf *mdev;
 449
 450         if (minor >= minor_count)
 451                 return NULL;
 452
 453         mdev = minor_to_mdev(minor);
 454
 455         if (!mdev && create) {
 456                 struct gendisk *disk = NULL;
 457                 mdev = drbd_new_device(minor);
 458
 459                 spin_lock_irq(&drbd_pp_lock);
 460                 if (minor_table[minor] == NULL) {
 461                         minor_table[minor] = mdev;
 462                         disk = mdev->vdisk;
 463                         mdev = NULL;
 464                 } /* else: we lost the race */
 465                 spin_unlock_irq(&drbd_pp_lock);
 466
 467                 if (disk) /* we won the race above */
 468                         /* in case we ever add a drbd_delete_device(),
 469                          * don't forget the del_gendisk! */
 470                         add_disk(disk);
 471                 else /* we lost the race above */
 472                         drbd_free_mdev(mdev);
 473
 474                 mdev = minor_to_mdev(minor);
 475         }
 476
 477         return mdev;
 478 }
 479
 480 static int drbd_nl_primary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
 481                            struct drbd_nl_cfg_reply *reply)
 482 {
 483         struct primary primary_args;
 484
 485         memset(&primary_args, 0, sizeof(struct primary));
 486         if (!primary_from_tags(mdev, nlp->tag_list, &primary_args)) {
 487                 reply->ret_code = ERR_MANDATORY_TAG;
 488                 return 0;
 489         }
 490
 491         reply->ret_code =
 492                 drbd_set_role(mdev, R_PRIMARY, primary_args.primary_force);
 493
 494         return 0;
 495 }
 496
 497 static int drbd_nl_secondary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
 498                              struct drbd_nl_cfg_reply *reply)
 499 {
 500         reply->ret_code = drbd_set_role(mdev, R_SECONDARY, 0);
 501
 502         return 0;
 503 }
 504
 505 /* initializes the md.*_offset members, so we are able to find
 506  * the on disk meta data */
 507 static void drbd_md_set_sector_offsets(struct drbd_conf *mdev,
 508                                        struct drbd_backing_dev *bdev)
 509 {
 510         sector_t md_size_sect = 0;
 511         switch (bdev->dc.meta_dev_idx) {
 512         default:
 513                 /* v07 style fixed size indexed meta data */
 514                 bdev->md.md_size_sect = MD_RESERVED_SECT;
 515                 bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
 516                 bdev->md.al_offset = MD_AL_OFFSET;
 517                 bdev->md.bm_offset = MD_BM_OFFSET;
 518                 break;
 519         case DRBD_MD_INDEX_FLEX_EXT:
 520                 /* just occupy the full device; unit: sectors */
 521                 bdev->md.md_size_sect = drbd_get_capacity(bdev->md_bdev);
 522                 bdev->md.md_offset = 0;
 523                 bdev->md.al_offset = MD_AL_OFFSET;
 524                 bdev->md.bm_offset = MD_BM_OFFSET;
 525                 break;
 526         case DRBD_MD_INDEX_INTERNAL:
 527         case DRBD_MD_INDEX_FLEX_INT:
 528                 bdev->md.md_offset = drbd_md_ss__(mdev, bdev);
 529                 /* al size is still fixed */
 530                 bdev->md.al_offset = -MD_AL_MAX_SIZE;
 531                 /* we need (slightly less than) ~ this much bitmap sectors: */
 532                 md_size_sect = drbd_get_capacity(bdev->backing_bdev);
 533                 md_size_sect = ALIGN(md_size_sect, BM_SECT_PER_EXT);
 534                 md_size_sect = BM_SECT_TO_EXT(md_size_sect);
 535                 md_size_sect = ALIGN(md_size_sect, 8);
 536
 537                 /* plus the "drbd meta data super block",
 538                  * and the activity log; */
 539                 md_size_sect += MD_BM_OFFSET;
 540
 541                 bdev->md.md_size_sect = md_size_sect;
 542                 /* bitmap offset is adjusted by 'super' block size */
 543                 bdev->md.bm_offset   = -md_size_sect + MD_AL_OFFSET;
 544                 break;
 545         }
 546 }
 547
 548 /* input size is expected to be in KB */
 549 char *ppsize(char *buf, unsigned long long size)
 550 {
 551         /* Needs 9 bytes at max including trailing NUL:
 552          * -1ULL ==> "16384 EB" */
 553         static char units[] = { 'K', 'M', 'G', 'T', 'P', 'E' };
 554         int base = 0;
 555         while (size >= 10000 && base < sizeof(units)-1) {
 556                 /* shift + round */
 557                 size = (size >> 10) + !!(size & (1<<9));
 558                 base++;
 559         }
 560         sprintf(buf, "%u %cB", (unsigned)size, units[base]);
 561
 562         return buf;
 563 }
 564
 565 /* there is still a theoretical deadlock when called from receiver
 566  * on an D_INCONSISTENT R_PRIMARY:
 567  *  remote READ does inc_ap_bio, receiver would need to receive answer
 568  *  packet from remote to dec_ap_bio again.
 569  *  receiver receive_sizes(), comes here,
 570  *  waits for ap_bio_cnt == 0. -> deadlock.
 571  * but this cannot happen, actually, because:
 572  *  R_PRIMARY D_INCONSISTENT, and peer's disk is unreachable
 573  *  (not connected, or bad/no disk on peer):
 574  *  see drbd_fail_request_early, ap_bio_cnt is zero.
 575  *  R_PRIMARY D_INCONSISTENT, and C_SYNC_TARGET:
 576  *  peer may not initiate a resize.
 577  */
 578 void drbd_suspend_io(struct drbd_conf *mdev)
 579 {
 580         set_bit(SUSPEND_IO, &mdev->flags);
 581         if (is_susp(mdev->state))
 582                 return;
 583         wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt));
 584 }
 585
 586 void drbd_resume_io(struct drbd_conf *mdev)
 587 {
 588         clear_bit(SUSPEND_IO, &mdev->flags);
 589         wake_up(&mdev->misc_wait);
 590 }
 591
 592 /**
 593  * drbd_determine_dev_size() -  Sets the right device size obeying all constraints
 594  * @mdev:       DRBD device.
 595  *
 596  * Returns 0 on success, negative return values indicate errors.
 597  * You should call drbd_md_sync() after calling this function.
 598  */
 599 enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *mdev, enum dds_flags flags) __must_hold(local)
 600 {
 601         sector_t prev_first_sect, prev_size; /* previous meta location */
 602         sector_t la_size;
 603         sector_t size;
 604         char ppb[10];
 605
 606         int md_moved, la_size_changed;
 607         enum determine_dev_size rv = unchanged;
 608
 609         /* race:
 610          * application request passes inc_ap_bio,
 611          * but then cannot get an AL-reference.
 612          * this function later may wait on ap_bio_cnt == 0. -> deadlock.
 613          *
 614          * to avoid that:
 615          * Suspend IO right here.
 616          * still lock the act_log to not trigger ASSERTs there.
 617          */
 618         drbd_suspend_io(mdev);
 619
 620         /* no wait necessary anymore, actually we could assert that */
 621         wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
 622
 623         prev_first_sect = drbd_md_first_sector(mdev->ldev);
 624         prev_size = mdev->ldev->md.md_size_sect;
 625         la_size = mdev->ldev->md.la_size_sect;
 626
 627         /* TODO: should only be some assert here, not (re)init... */
 628         drbd_md_set_sector_offsets(mdev, mdev->ldev);
 629
 630         size = drbd_new_dev_size(mdev, mdev->ldev, flags & DDSF_FORCED);
 631
 632         if (drbd_get_capacity(mdev->this_bdev) != size ||
 633             drbd_bm_capacity(mdev) != size) {
 634                 int err;
 635                 err = drbd_bm_resize(mdev, size, !(flags & DDSF_NO_RESYNC));
 636                 if (unlikely(err)) {
 637                         /* currently there is only one error: ENOMEM! */
 638                         size = drbd_bm_capacity(mdev)>>1;
 639                         if (size == 0) {
 640                                 dev_err(DEV, "OUT OF MEMORY! "
 641                                     "Could not allocate bitmap!\n");
 642                         } else {
 643                                 dev_err(DEV, "BM resizing failed. "
 644                                     "Leaving size unchanged at size = %lu KB\n",
 645                                     (unsigned long)size);
 646                         }
 647                         rv = dev_size_error;
 648                 }
 649                 /* racy, see comments above. */
 650                 drbd_set_my_capacity(mdev, size);
 651                 mdev->ldev->md.la_size_sect = size;
 652                 dev_info(DEV, "size = %s (%llu KB)\n", ppsize(ppb, size>>1),
 653                      (unsigned long long)size>>1);
 654         }
 655         if (rv == dev_size_error)
 656                 goto out;
 657
 658         la_size_changed = (la_size != mdev->ldev->md.la_size_sect);
 659
 660         md_moved = prev_first_sect != drbd_md_first_sector(mdev->ldev)
 661                 || prev_size       != mdev->ldev->md.md_size_sect;
 662
 663         if (la_size_changed || md_moved) {
 664                 int err;
 665
 666                 drbd_al_shrink(mdev); /* All extents inactive. */
 667                 dev_info(DEV, "Writing the whole bitmap, %s\n",
 668                          la_size_changed && md_moved ? "size changed and md moved" :
 669                          la_size_changed ? "size changed" : "md moved");
 670                 /* next line implicitly does drbd_suspend_io()+drbd_resume_io() */
 671                 err = drbd_bitmap_io(mdev, &drbd_bm_write,
 672                                 "size changed", BM_LOCKED_MASK);
 673                 if (err) {
 674                         rv = dev_size_error;
 675                         goto out;
 676                 }
 677                 drbd_md_mark_dirty(mdev);
 678         }
 679
 680         if (size > la_size)
 681                 rv = grew;
 682         if (size < la_size)
 683                 rv = shrunk;
 684 out:
 685         lc_unlock(mdev->act_log);
 686         wake_up(&mdev->al_wait);
 687         drbd_resume_io(mdev);
 688
 689         return rv;
 690 }
 691
 692 sector_t
 693 drbd_new_dev_size(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, int assume_peer_has_space)
 694 {
 695         sector_t p_size = mdev->p_size;   /* partner's disk size. */
 696         sector_t la_size = bdev->md.la_size_sect; /* last agreed size. */
 697         sector_t m_size; /* my size */
 698         sector_t u_size = bdev->dc.disk_size; /* size requested by user. */
 699         sector_t size = 0;
 700
 701         m_size = drbd_get_max_capacity(bdev);
 702
 703         if (mdev->state.conn < C_CONNECTED && assume_peer_has_space) {
 704                 dev_warn(DEV, "Resize while not connected was forced by the user!\n");
 705                 p_size = m_size;
 706         }
 707
 708         if (p_size && m_size) {
 709                 size = min_t(sector_t, p_size, m_size);
 710         } else {
 711                 if (la_size) {
 712                         size = la_size;
 713                         if (m_size && m_size < size)
 714                                 size = m_size;
 715                         if (p_size && p_size < size)
 716                                 size = p_size;
 717                 } else {
 718                         if (m_size)
 719                                 size = m_size;
 720                         if (p_size)
 721                                 size = p_size;
 722                 }
 723         }
 724
 725         if (size == 0)
 726                 dev_err(DEV, "Both nodes diskless!\n");
 727
 728         if (u_size) {
 729                 if (u_size > size)
 730                         dev_err(DEV, "Requested disk size is too big (%lu > %lu)\n",
 731                             (unsigned long)u_size>>1, (unsigned long)size>>1);
 732                 else
 733                         size = u_size;
 734         }
 735
 736         return size;
 737 }
 738
 739 /**
 740  * drbd_check_al_size() - Ensures that the AL is of the right size
 741  * @mdev:       DRBD device.
 742  *
 743  * Returns -EBUSY if current al lru is still used, -ENOMEM when allocation
 744  * failed, and 0 on success. You should call drbd_md_sync() after you called
 745  * this function.
 746  */
 747 static int drbd_check_al_size(struct drbd_conf *mdev)
 748 {
 749         struct lru_cache *n, *t;
 750         struct lc_element *e;
 751         unsigned int in_use;
 752         int i;
 753
 754         ERR_IF(mdev->sync_conf.al_extents < 7)
 755                 mdev->sync_conf.al_extents = 127;
 756
 757         if (mdev->act_log &&
 758             mdev->act_log->nr_elements == mdev->sync_conf.al_extents)
 759                 return 0;
 760
 761         in_use = 0;
 762         t = mdev->act_log;
 763         n = lc_create("act_log", drbd_al_ext_cache,
 764                 mdev->sync_conf.al_extents, sizeof(struct lc_element), 0);
 765
 766         if (n == NULL) {
 767                 dev_err(DEV, "Cannot allocate act_log lru!\n");
 768                 return -ENOMEM;
 769         }
 770         spin_lock_irq(&mdev->al_lock);
 771         if (t) {
 772                 for (i = 0; i < t->nr_elements; i++) {
 773                         e = lc_element_by_index(t, i);
 774                         if (e->refcnt)
 775                                 dev_err(DEV, "refcnt(%d)==%d\n",
 776                                     e->lc_number, e->refcnt);
 777                         in_use += e->refcnt;
 778                 }
 779         }
 780         if (!in_use)
 781                 mdev->act_log = n;
 782         spin_unlock_irq(&mdev->al_lock);
 783         if (in_use) {
 784                 dev_err(DEV, "Activity log still in use!\n");
 785                 lc_destroy(n);
 786                 return -EBUSY;
 787         } else {
 788                 if (t)
 789                         lc_destroy(t);
 790         }
 791         drbd_md_mark_dirty(mdev); /* we changed mdev->act_log->nr_elemens */
 792         return 0;
 793 }
 794
 795 static void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_bio_size)
 796 {
 797         struct request_queue * const q = mdev->rq_queue;
 798         int max_hw_sectors = max_bio_size >> 9;
 799         int max_segments = 0;
 800
 801         if (get_ldev_if_state(mdev, D_ATTACHING)) {
 802                 struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
 803
 804                 max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9);
 805                 max_segments = mdev->ldev->dc.max_bio_bvecs;
 806                 put_ldev(mdev);
 807         }
 808
 809         blk_queue_logical_block_size(q, 512);
 810         blk_queue_max_hw_sectors(q, max_hw_sectors);
 811         /* This is the workaround for "bio would need to, but cannot, be split" */
 812         blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
 813         blk_queue_segment_boundary(q, PAGE_CACHE_SIZE-1);
 814
 815         if (get_ldev_if_state(mdev, D_ATTACHING)) {
 816                 struct request_queue * const b = mdev->ldev->backing_bdev->bd_disk->queue;
 817
 818                 blk_queue_stack_limits(q, b);
 819
 820                 if (q->backing_dev_info.ra_pages != b->backing_dev_info.ra_pages) {
 821                         dev_info(DEV, "Adjusting my ra_pages to backing device's (%lu -> %lu)\n",
 822                                  q->backing_dev_info.ra_pages,
 823                                  b->backing_dev_info.ra_pages);
 824                         q->backing_dev_info.ra_pages = b->backing_dev_info.ra_pages;
 825                 }
 826                 put_ldev(mdev);
 827         }
 828 }
 829
 830 void drbd_reconsider_max_bio_size(struct drbd_conf *mdev)
 831 {
 832         int now, new, local, peer;
 833
 834         now = queue_max_hw_sectors(mdev->rq_queue) << 9;
 835         local = mdev->local_max_bio_size; /* Eventually last known value, from volatile memory */
 836         peer = mdev->peer_max_bio_size; /* Eventually last known value, from meta data */
 837
 838         if (get_ldev_if_state(mdev, D_ATTACHING)) {
 839                 local = queue_max_hw_sectors(mdev->ldev->backing_bdev->bd_disk->queue) << 9;
 840                 mdev->local_max_bio_size = local;
 841                 put_ldev(mdev);
 842         }
 843
 844         /* We may ignore peer limits if the peer is modern enough.
 845            Because new from 8.3.8 onwards the peer can use multiple
 846            BIOs for a single peer_request */
 847         if (mdev->state.conn >= C_CONNECTED) {
 848                 if (mdev->agreed_pro_version < 94)
 849                         peer = mdev->peer_max_bio_size;
 850                 else if (mdev->agreed_pro_version == 94)
 851                         peer = DRBD_MAX_SIZE_H80_PACKET;
 852                 else /* drbd 8.3.8 onwards */
 853                         peer = DRBD_MAX_BIO_SIZE;
 854         }
 855
 856         new = min_t(int, local, peer);
 857
 858         if (mdev->state.role == R_PRIMARY && new < now)
 859                 dev_err(DEV, "ASSERT FAILED new < now; (%d < %d)\n", new, now);
 860
 861         if (new != now)
 862                 dev_info(DEV, "max BIO size = %u\n", new);
 863
 864         drbd_setup_queue_param(mdev, new);
 865 }
 866
 867 /* serialize deconfig (worker exiting, doing cleanup)
 868  * and reconfig (drbdsetup disk, drbdsetup net)
 869  *
 870  * Wait for a potentially exiting worker, then restart it,
 871  * or start a new one.  Flush any pending work, there may still be an
 872  * after_state_change queued.
 873  */
 874 static void drbd_reconfig_start(struct drbd_conf *mdev)
 875 {
 876         wait_event(mdev->state_wait, !test_and_set_bit(CONFIG_PENDING, &mdev->flags));
 877         wait_event(mdev->state_wait, !test_bit(DEVICE_DYING, &mdev->flags));
 878         drbd_thread_start(&mdev->worker);
 879         drbd_flush_workqueue(mdev);
 880 }
 881
 882 /* if still unconfigured, stops worker again.
 883  * if configured now, clears CONFIG_PENDING.
 884  * wakes potential waiters */
 885 static void drbd_reconfig_done(struct drbd_conf *mdev)
 886 {
 887         spin_lock_irq(&mdev->req_lock);
 888         if (mdev->state.disk == D_DISKLESS &&
 889             mdev->state.conn == C_STANDALONE &&
 890             mdev->state.role == R_SECONDARY) {
 891                 set_bit(DEVICE_DYING, &mdev->flags);
 892                 drbd_thread_stop_nowait(&mdev->worker);
 893         } else
 894                 clear_bit(CONFIG_PENDING, &mdev->flags);
 895         spin_unlock_irq(&mdev->req_lock);
 896         wake_up(&mdev->state_wait);
 897 }
 898
 899 /* Make sure IO is suspended before calling this function(). */
 900 static void drbd_suspend_al(struct drbd_conf *mdev)
 901 {
 902         int s = 0;
 903
 904         if (lc_try_lock(mdev->act_log)) {
 905                 drbd_al_shrink(mdev);
 906                 lc_unlock(mdev->act_log);
 907         } else {
 908                 dev_warn(DEV, "Failed to lock al in drbd_suspend_al()\n");
 909                 return;
 910         }
 911
 912         spin_lock_irq(&mdev->req_lock);
 913         if (mdev->state.conn < C_CONNECTED)
 914                 s = !test_and_set_bit(AL_SUSPENDED, &mdev->flags);
 915
 916         spin_unlock_irq(&mdev->req_lock);
 917
 918         if (s)
 919                 dev_info(DEV, "Suspended AL updates\n");
 920 }
 921
 922 /* does always return 0;
 923  * interesting return code is in reply->ret_code */
 924 static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
 925                              struct drbd_nl_cfg_reply *reply)
 926 {
 927         enum drbd_ret_code retcode;
 928         enum determine_dev_size dd;
 929         sector_t max_possible_sectors;
 930         sector_t min_md_device_sectors;
 931         struct drbd_backing_dev *nbc = NULL; /* new_backing_conf */
 932         struct block_device *bdev;
 933         struct lru_cache *resync_lru = NULL;
 934         union drbd_state ns, os;
 935         enum drbd_state_rv rv;
 936         int cp_discovered = 0;
 937         int logical_block_size;
 938
 939         drbd_reconfig_start(mdev);
 940
 941         /* if you want to reconfigure, please tear down first */
 942         if (mdev->state.disk > D_DISKLESS) {
 943                 retcode = ERR_DISK_CONFIGURED;
 944                 goto fail;
 945         }
 946         /* It may just now have detached because of IO error.  Make sure
 947          * drbd_ldev_destroy is done already, we may end up here very fast,
 948          * e.g. if someone calls attach from the on-io-error handler,
 949          * to realize a "hot spare" feature (not that I'd recommend that) */
 950         wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
 951
 952         /* allocation not in the IO path, cqueue thread context */
 953         nbc = kzalloc(sizeof(struct drbd_backing_dev), GFP_KERNEL);
 954         if (!nbc) {
 955                 retcode = ERR_NOMEM;
 956                 goto fail;
 957         }
 958
 959         nbc->dc.disk_size     = DRBD_DISK_SIZE_SECT_DEF;
 960         nbc->dc.on_io_error   = DRBD_ON_IO_ERROR_DEF;
 961         nbc->dc.fencing       = DRBD_FENCING_DEF;
 962         nbc->dc.max_bio_bvecs = DRBD_MAX_BIO_BVECS_DEF;
 963
 964         if (!disk_conf_from_tags(mdev, nlp->tag_list, &nbc->dc)) {
 965                 retcode = ERR_MANDATORY_TAG;
 966                 goto fail;
 967         }
 968
 969         if (nbc->dc.meta_dev_idx < DRBD_MD_INDEX_FLEX_INT) {
 970                 retcode = ERR_MD_IDX_INVALID;
 971                 goto fail;
 972         }
 973
 974         if (get_net_conf(mdev)) {
 975                 int prot = mdev->net_conf->wire_protocol;
 976                 put_net_conf(mdev);
 977                 if (nbc->dc.fencing == FP_STONITH && prot == DRBD_PROT_A) {
 978                         retcode = ERR_STONITH_AND_PROT_A;
 979                         goto fail;
 980                 }
 981         }
 982
 983         bdev = blkdev_get_by_path(nbc->dc.backing_dev,
 984                                   FMODE_READ | FMODE_WRITE | FMODE_EXCL, mdev);
 985         if (IS_ERR(bdev)) {
 986                 dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.backing_dev,
 987                         PTR_ERR(bdev));
 988                 retcode = ERR_OPEN_DISK;
 989                 goto fail;
 990         }
 991         nbc->backing_bdev = bdev;
 992
 993         /*
 994          * meta_dev_idx >= 0: external fixed size, possibly multiple
 995          * drbd sharing one meta device.  TODO in that case, paranoia
 996          * check that [md_bdev, meta_dev_idx] is not yet used by some
 997          * other drbd minor!  (if you use drbd.conf + drbdadm, that
 998          * should check it for you already; but if you don't, or
 999          * someone fooled it, we need to double check here)
1000          */
1001         bdev = blkdev_get_by_path(nbc->dc.meta_dev,
1002                                   FMODE_READ | FMODE_WRITE | FMODE_EXCL,
1003                                   (nbc->dc.meta_dev_idx < 0) ?
1004                                   (void *)mdev : (void *)drbd_m_holder);
1005         if (IS_ERR(bdev)) {
1006                 dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.meta_dev,
1007                         PTR_ERR(bdev));
1008                 retcode = ERR_OPEN_MD_DISK;
1009                 goto fail;
1010         }
1011         nbc->md_bdev = bdev;
1012
1013         if ((nbc->backing_bdev == nbc->md_bdev) !=
1014             (nbc->dc.meta_dev_idx == DRBD_MD_INDEX_INTERNAL ||
1015              nbc->dc.meta_dev_idx == DRBD_MD_INDEX_FLEX_INT)) {
1016                 retcode = ERR_MD_IDX_INVALID;
1017                 goto fail;
1018         }
1019
1020         resync_lru = lc_create("resync", drbd_bm_ext_cache,
1021                         61, sizeof(struct bm_extent),
1022                         offsetof(struct bm_extent, lce));
1023         if (!resync_lru) {
1024                 retcode = ERR_NOMEM;
1025                 goto fail;
1026         }
1027
1028         /* RT - for drbd_get_max_capacity() DRBD_MD_INDEX_FLEX_INT */
1029         drbd_md_set_sector_offsets(mdev, nbc);
1030
1031         if (drbd_get_max_capacity(nbc) < nbc->dc.disk_size) {
1032                 dev_err(DEV, "max capacity %llu smaller than disk size %llu\n",
1033                         (unsigned long long) drbd_get_max_capacity(nbc),
1034                         (unsigned long long) nbc->dc.disk_size);
1035                 retcode = ERR_DISK_TO_SMALL;
1036                 goto fail;
1037         }
1038
1039         if (nbc->dc.meta_dev_idx < 0) {
1040                 max_possible_sectors = DRBD_MAX_SECTORS_FLEX;
1041                 /* at least one MB, otherwise it does not make sense */
1042                 min_md_device_sectors = (2<<10);
1043         } else {
1044                 max_possible_sectors = DRBD_MAX_SECTORS;
1045                 min_md_device_sectors = MD_RESERVED_SECT * (nbc->dc.meta_dev_idx + 1);
1046         }
1047
1048         if (drbd_get_capacity(nbc->md_bdev) < min_md_device_sectors) {
1049                 retcode = ERR_MD_DISK_TO_SMALL;
1050                 dev_warn(DEV, "refusing attach: md-device too small, "
1051                      "at least %llu sectors needed for this meta-disk type\n",
1052                      (unsigned long long) min_md_device_sectors);
1053                 goto fail;
1054         }
1055
1056         /* Make sure the new disk is big enough
1057          * (we may currently be R_PRIMARY with no local disk...) */
1058         if (drbd_get_max_capacity(nbc) <
1059             drbd_get_capacity(mdev->this_bdev)) {
1060                 retcode = ERR_DISK_TO_SMALL;
1061                 goto fail;
1062         }
1063
1064         nbc->known_size = drbd_get_capacity(nbc->backing_bdev);
1065
1066         if (nbc->known_size > max_possible_sectors) {
1067                 dev_warn(DEV, "==> truncating very big lower level device "
1068                         "to currently maximum possible %llu sectors <==\n",
1069                         (unsigned long long) max_possible_sectors);
1070                 if (nbc->dc.meta_dev_idx >= 0)
1071                         dev_warn(DEV, "==>> using internal or flexible "
1072                                       "meta data may help <<==\n");
1073         }
1074
1075         drbd_suspend_io(mdev);
1076         /* also wait for the last barrier ack. */
1077         wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_pending_cnt) || is_susp(mdev->state));
1078         /* and for any other previously queued work */
1079         drbd_flush_workqueue(mdev);
1080
1081         rv = _drbd_request_state(mdev, NS(disk, D_ATTACHING), CS_VERBOSE);
1082         retcode = rv;  /* FIXME: Type mismatch. */
1083         drbd_resume_io(mdev);
1084         if (rv < SS_SUCCESS)
1085                 goto fail;
1086
1087         if (!get_ldev_if_state(mdev, D_ATTACHING))
1088                 goto force_diskless;
1089
1090         drbd_md_set_sector_offsets(mdev, nbc);
1091
1092         /* allocate a second IO page if logical_block_size != 512 */
1093         logical_block_size = bdev_logical_block_size(nbc->md_bdev);
1094         if (logical_block_size == 0)
1095                 logical_block_size = MD_SECTOR_SIZE;
1096
1097         if (logical_block_size != MD_SECTOR_SIZE) {
1098                 if (!mdev->md_io_tmpp) {
1099                         struct page *page = alloc_page(GFP_NOIO);
1100                         if (!page)
1101                                 goto force_diskless_dec;
1102
1103                         dev_warn(DEV, "Meta data's bdev logical_block_size = %d != %d\n",
1104                              logical_block_size, MD_SECTOR_SIZE);
1105                         dev_warn(DEV, "Workaround engaged (has performance impact).\n");
1106
1107                         mdev->md_io_tmpp = page;
1108                 }
1109         }
1110
1111         if (!mdev->bitmap) {
1112                 if (drbd_bm_init(mdev)) {
1113                         retcode = ERR_NOMEM;
1114                         goto force_diskless_dec;
1115                 }
1116         }
1117
1118         retcode = drbd_md_read(mdev, nbc);
1119         if (retcode != NO_ERROR)
1120                 goto force_diskless_dec;
1121
1122         if (mdev->state.conn < C_CONNECTED &&
1123             mdev->state.role == R_PRIMARY &&
1124             (mdev->ed_uuid & ~((u64)1)) != (nbc->md.uuid[UI_CURRENT] & ~((u64)1))) {
1125                 dev_err(DEV, "Can only attach to data with current UUID=%016llX\n",
1126                     (unsigned long long)mdev->ed_uuid);
1127                 retcode = ERR_DATA_NOT_CURRENT;
1128                 goto force_diskless_dec;
1129         }
1130
1131         /* Since we are diskless, fix the activity log first... */
1132         if (drbd_check_al_size(mdev)) {
1133                 retcode = ERR_NOMEM;
1134                 goto force_diskless_dec;
1135         }
1136
1137         /* Prevent shrinking of consistent devices ! */
1138         if (drbd_md_test_flag(nbc, MDF_CONSISTENT) &&
1139             drbd_new_dev_size(mdev, nbc, 0) < nbc->md.la_size_sect) {
1140                 dev_warn(DEV, "refusing to truncate a consistent device\n");
1141                 retcode = ERR_DISK_TO_SMALL;
1142                 goto force_diskless_dec;
1143         }
1144
1145         if (!drbd_al_read_log(mdev, nbc)) {
1146                 retcode = ERR_IO_MD_DISK;
1147                 goto force_diskless_dec;
1148         }
1149
1150         /* Reset the "barriers don't work" bits here, then force meta data to
1151          * be written, to ensure we determine if barriers are supported. */
1152         if (nbc->dc.no_md_flush)
1153                 set_bit(MD_NO_FUA, &mdev->flags);
1154         else
1155                 clear_bit(MD_NO_FUA, &mdev->flags);
1156
1157         /* Point of no return reached.
1158          * Devices and memory are no longer released by error cleanup below.
1159          * now mdev takes over responsibility, and the state engine should
1160          * clean it up somewhere.  */
1161         D_ASSERT(mdev->ldev == NULL);
1162         mdev->ldev = nbc;
1163         mdev->resync = resync_lru;
1164         nbc = NULL;
1165         resync_lru = NULL;
1166
1167         mdev->write_ordering = WO_bdev_flush;
1168         drbd_bump_write_ordering(mdev, WO_bdev_flush);
1169
1170         if (drbd_md_test_flag(mdev->ldev, MDF_CRASHED_PRIMARY))
1171                 set_bit(CRASHED_PRIMARY, &mdev->flags);
1172         else
1173                 clear_bit(CRASHED_PRIMARY, &mdev->flags);
1174
1175         if (drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
1176             !(mdev->state.role == R_PRIMARY && mdev->state.susp_nod)) {
1177                 set_bit(CRASHED_PRIMARY, &mdev->flags);
1178                 cp_discovered = 1;
1179         }
1180
1181         mdev->send_cnt = 0;
1182         mdev->recv_cnt = 0;
1183         mdev->read_cnt = 0;
1184         mdev->writ_cnt = 0;
1185
1186         drbd_reconsider_max_bio_size(mdev);
1187
1188         /* If I am currently not R_PRIMARY,
1189          * but meta data primary indicator is set,
1190          * I just now recover from a hard crash,
1191          * and have been R_PRIMARY before that crash.
1192          *
1193          * Now, if I had no connection before that crash
1194          * (have been degraded R_PRIMARY), chances are that
1195          * I won't find my peer now either.
1196          *
1197          * In that case, and _only_ in that case,
1198          * we use the degr-wfc-timeout instead of the default,
1199          * so we can automatically recover from a crash of a
1200          * degraded but active "cluster" after a certain timeout.
1201          */
1202         clear_bit(USE_DEGR_WFC_T, &mdev->flags);
1203         if (mdev->state.role != R_PRIMARY &&
1204              drbd_md_test_flag(mdev->ldev, MDF_PRIMARY_IND) &&
1205             !drbd_md_test_flag(mdev->ldev, MDF_CONNECTED_IND))
1206                 set_bit(USE_DEGR_WFC_T, &mdev->flags);
1207
1208         dd = drbd_determin_dev_size(mdev, 0);
1209         if (dd == dev_size_error) {
1210                 retcode = ERR_NOMEM_BITMAP;
1211                 goto force_diskless_dec;
1212         } else if (dd == grew)
1213                 set_bit(RESYNC_AFTER_NEG, &mdev->flags);
1214
1215         if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
1216                 dev_info(DEV, "Assuming that all blocks are out of sync "
1217                      "(aka FullSync)\n");
1218                 if (drbd_bitmap_io(mdev, &drbd_bmio_set_n_write,
1219                         "set_n_write from attaching", BM_LOCKED_MASK)) {
1220                         retcode = ERR_IO_MD_DISK;
1221                         goto force_diskless_dec;
1222                 }
1223         } else {
1224                 if (drbd_bitmap_io(mdev, &drbd_bm_read,
1225                         "read from attaching", BM_LOCKED_MASK) < 0) {
1226                         retcode = ERR_IO_MD_DISK;
1227                         goto force_diskless_dec;
1228                 }
1229         }
1230
1231         if (cp_discovered) {
1232                 drbd_al_apply_to_bm(mdev);
1233                 if (drbd_bitmap_io(mdev, &drbd_bm_write,
1234                         "crashed primary apply AL", BM_LOCKED_MASK)) {
1235                         retcode = ERR_IO_MD_DISK;
1236                         goto force_diskless_dec;
1237                 }
1238         }
1239
1240         if (_drbd_bm_total_weight(mdev) == drbd_bm_bits(mdev))
1241                 drbd_suspend_al(mdev); /* IO is still suspended here... */
1242
1243         spin_lock_irq(&mdev->req_lock);
1244         os = mdev->state;
1245         ns.i = os.i;
1246         /* If MDF_CONSISTENT is not set go into inconsistent state,
1247            otherwise investigate MDF_WasUpToDate...
1248            If MDF_WAS_UP_TO_DATE is not set go into D_OUTDATED disk state,
1249            otherwise into D_CONSISTENT state.
1250         */
1251         if (drbd_md_test_flag(mdev->ldev, MDF_CONSISTENT)) {
1252                 if (drbd_md_test_flag(mdev->ldev, MDF_WAS_UP_TO_DATE))
1253                         ns.disk = D_CONSISTENT;
1254                 else
1255                         ns.disk = D_OUTDATED;
1256         } else {
1257                 ns.disk = D_INCONSISTENT;
1258         }
1259
1260         if (drbd_md_test_flag(mdev->ldev, MDF_PEER_OUT_DATED))
1261                 ns.pdsk = D_OUTDATED;
1262
1263         if ( ns.disk == D_CONSISTENT &&
1264             (ns.pdsk == D_OUTDATED || mdev->ldev->dc.fencing == FP_DONT_CARE))
1265                 ns.disk = D_UP_TO_DATE;
1266
1267         /* All tests on MDF_PRIMARY_IND, MDF_CONNECTED_IND,
1268            MDF_CONSISTENT and MDF_WAS_UP_TO_DATE must happen before
1269            this point, because drbd_request_state() modifies these
1270            flags. */
1271
1272         /* In case we are C_CONNECTED postpone any decision on the new disk
1273            state after the negotiation phase. */
1274         if (mdev->state.conn == C_CONNECTED) {
1275                 mdev->new_state_tmp.i = ns.i;
1276                 ns.i = os.i;
1277                 ns.disk = D_NEGOTIATING;
1278
1279                 /* We expect to receive up-to-date UUIDs soon.
1280                    To avoid a race in receive_state, free p_uuid while
1281                    holding req_lock. I.e. atomic with the state change */
1282                 kfree(mdev->p_uuid);
1283                 mdev->p_uuid = NULL;
1284         }
1285
1286         rv = _drbd_set_state(mdev, ns, CS_VERBOSE, NULL);
1287         ns = mdev->state;
1288         spin_unlock_irq(&mdev->req_lock);
1289
1290         if (rv < SS_SUCCESS)
1291                 goto force_diskless_dec;
1292
1293         if (mdev->state.role == R_PRIMARY)
1294                 mdev->ldev->md.uuid[UI_CURRENT] |=  (u64)1;
1295         else
1296                 mdev->ldev->md.uuid[UI_CURRENT] &= ~(u64)1;
1297
1298         drbd_md_mark_dirty(mdev);
1299         drbd_md_sync(mdev);
1300
1301         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1302         put_ldev(mdev);
1303         reply->ret_code = retcode;
1304         drbd_reconfig_done(mdev);
1305         return 0;
1306
1307  force_diskless_dec:
1308         put_ldev(mdev);
1309  force_diskless:
1310         drbd_force_state(mdev, NS(disk, D_FAILED));
1311         drbd_md_sync(mdev);
1312  fail:
1313         if (nbc) {
1314                 if (nbc->backing_bdev)
1315                         blkdev_put(nbc->backing_bdev,
1316                                    FMODE_READ | FMODE_WRITE | FMODE_EXCL);
1317                 if (nbc->md_bdev)
1318                         blkdev_put(nbc->md_bdev,
1319                                    FMODE_READ | FMODE_WRITE | FMODE_EXCL);
1320                 kfree(nbc);
1321         }
1322         lc_destroy(resync_lru);
1323
1324         reply->ret_code = retcode;
1325         drbd_reconfig_done(mdev);
1326         return 0;
1327 }
1328
1329 /* Detaching the disk is a process in multiple stages.  First we need to lock
1330  * out application IO, in-flight IO, IO stuck in drbd_al_begin_io.
1331  * Then we transition to D_DISKLESS, and wait for put_ldev() to return all
1332  * internal references as well.
1333  * Only then we have finally detached. */
1334 static int drbd_nl_detach(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1335                           struct drbd_nl_cfg_reply *reply)
1336 {
1337         drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */
1338         reply->ret_code = drbd_request_state(mdev, NS(disk, D_DISKLESS));
1339         if (mdev->state.disk == D_DISKLESS)
1340                 wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
1341         drbd_resume_io(mdev);
1342         return 0;
1343 }
1344
1345 static int drbd_nl_net_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1346                             struct drbd_nl_cfg_reply *reply)
1347 {
1348         int i, ns;
1349         enum drbd_ret_code retcode;
1350         struct net_conf *new_conf = NULL;
1351         struct crypto_hash *tfm = NULL;
1352         struct crypto_hash *integrity_w_tfm = NULL;
1353         struct crypto_hash *integrity_r_tfm = NULL;
1354         struct hlist_head *new_tl_hash = NULL;
1355         struct hlist_head *new_ee_hash = NULL;
1356         struct drbd_conf *odev;
1357         char hmac_name[CRYPTO_MAX_ALG_NAME];
1358         void *int_dig_out = NULL;
1359         void *int_dig_in = NULL;
1360         void *int_dig_vv = NULL;
1361         struct sockaddr *new_my_addr, *new_peer_addr, *taken_addr;
1362
1363         drbd_reconfig_start(mdev);
1364
1365         if (mdev->state.conn > C_STANDALONE) {
1366                 retcode = ERR_NET_CONFIGURED;
1367                 goto fail;
1368         }
1369
1370         /* allocation not in the IO path, cqueue thread context */
1371         new_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
1372         if (!new_conf) {
1373                 retcode = ERR_NOMEM;
1374                 goto fail;
1375         }
1376
1377         new_conf->timeout          = DRBD_TIMEOUT_DEF;
1378         new_conf->try_connect_int  = DRBD_CONNECT_INT_DEF;
1379         new_conf->ping_int         = DRBD_PING_INT_DEF;
1380         new_conf->max_epoch_size   = DRBD_MAX_EPOCH_SIZE_DEF;
1381         new_conf->max_buffers      = DRBD_MAX_BUFFERS_DEF;
1382         new_conf->unplug_watermark = DRBD_UNPLUG_WATERMARK_DEF;
1383         new_conf->sndbuf_size      = DRBD_SNDBUF_SIZE_DEF;
1384         new_conf->rcvbuf_size      = DRBD_RCVBUF_SIZE_DEF;
1385         new_conf->ko_count         = DRBD_KO_COUNT_DEF;
1386         new_conf->after_sb_0p      = DRBD_AFTER_SB_0P_DEF;
1387         new_conf->after_sb_1p      = DRBD_AFTER_SB_1P_DEF;
1388         new_conf->after_sb_2p      = DRBD_AFTER_SB_2P_DEF;
1389         new_conf->want_lose        = 0;
1390         new_conf->two_primaries    = 0;
1391         new_conf->wire_protocol    = DRBD_PROT_C;
1392         new_conf->ping_timeo       = DRBD_PING_TIMEO_DEF;
1393         new_conf->rr_conflict      = DRBD_RR_CONFLICT_DEF;
1394         new_conf->on_congestion    = DRBD_ON_CONGESTION_DEF;
1395         new_conf->cong_extents     = DRBD_CONG_EXTENTS_DEF;
1396
1397         if (!net_conf_from_tags(mdev, nlp->tag_list, new_conf)) {
1398                 retcode = ERR_MANDATORY_TAG;
1399                 goto fail;
1400         }
1401
1402         if (new_conf->two_primaries
1403             && (new_conf->wire_protocol != DRBD_PROT_C)) {
1404                 retcode = ERR_NOT_PROTO_C;
1405                 goto fail;
1406         }
1407
1408         if (get_ldev(mdev)) {
1409                 enum drbd_fencing_p fp = mdev->ldev->dc.fencing;
1410                 put_ldev(mdev);
1411                 if (new_conf->wire_protocol == DRBD_PROT_A && fp == FP_STONITH) {
1412                         retcode = ERR_STONITH_AND_PROT_A;
1413                         goto fail;
1414                 }
1415         }
1416
1417         if (new_conf->on_congestion != OC_BLOCK && new_conf->wire_protocol != DRBD_PROT_A) {
1418                 retcode = ERR_CONG_NOT_PROTO_A;
1419                 goto fail;
1420         }
1421
1422         if (mdev->state.role == R_PRIMARY && new_conf->want_lose) {
1423                 retcode = ERR_DISCARD;
1424                 goto fail;
1425         }
1426
1427         retcode = NO_ERROR;
1428
1429         new_my_addr = (struct sockaddr *)&new_conf->my_addr;
1430         new_peer_addr = (struct sockaddr *)&new_conf->peer_addr;
1431         for (i = 0; i < minor_count; i++) {
1432                 odev = minor_to_mdev(i);
1433                 if (!odev || odev == mdev)
1434                         continue;
1435                 if (get_net_conf(odev)) {
1436                         taken_addr = (struct sockaddr *)&odev->net_conf->my_addr;
1437                         if (new_conf->my_addr_len == odev->net_conf->my_addr_len &&
1438                             !memcmp(new_my_addr, taken_addr, new_conf->my_addr_len))
1439                                 retcode = ERR_LOCAL_ADDR;
1440
1441                         taken_addr = (struct sockaddr *)&odev->net_conf->peer_addr;
1442                         if (new_conf->peer_addr_len == odev->net_conf->peer_addr_len &&
1443                             !memcmp(new_peer_addr, taken_addr, new_conf->peer_addr_len))
1444                                 retcode = ERR_PEER_ADDR;
1445
1446                         put_net_conf(odev);
1447                         if (retcode != NO_ERROR)
1448                                 goto fail;
1449                 }
1450         }
1451
1452         if (new_conf->cram_hmac_alg[0] != 0) {
1453                 snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",
1454                         new_conf->cram_hmac_alg);
1455                 tfm = crypto_alloc_hash(hmac_name, 0, CRYPTO_ALG_ASYNC);
1456                 if (IS_ERR(tfm)) {
1457                         tfm = NULL;
1458                         retcode = ERR_AUTH_ALG;
1459                         goto fail;
1460                 }
1461
1462                 if (!drbd_crypto_is_hash(crypto_hash_tfm(tfm))) {
1463                         retcode = ERR_AUTH_ALG_ND;
1464                         goto fail;
1465                 }
1466         }
1467
1468         if (new_conf->integrity_alg[0]) {
1469                 integrity_w_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1470                 if (IS_ERR(integrity_w_tfm)) {
1471                         integrity_w_tfm = NULL;
1472                         retcode=ERR_INTEGRITY_ALG;
1473                         goto fail;
1474                 }
1475
1476                 if (!drbd_crypto_is_hash(crypto_hash_tfm(integrity_w_tfm))) {
1477                         retcode=ERR_INTEGRITY_ALG_ND;
1478                         goto fail;
1479                 }
1480
1481                 integrity_r_tfm = crypto_alloc_hash(new_conf->integrity_alg, 0, CRYPTO_ALG_ASYNC);
1482                 if (IS_ERR(integrity_r_tfm)) {
1483                         integrity_r_tfm = NULL;
1484                         retcode=ERR_INTEGRITY_ALG;
1485                         goto fail;
1486                 }
1487         }
1488
1489         ns = new_conf->max_epoch_size/8;
1490         if (mdev->tl_hash_s != ns) {
1491                 new_tl_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1492                 if (!new_tl_hash) {
1493                         retcode = ERR_NOMEM;
1494                         goto fail;
1495                 }
1496         }
1497
1498         ns = new_conf->max_buffers/8;
1499         if (new_conf->two_primaries && (mdev->ee_hash_s != ns)) {
1500                 new_ee_hash = kzalloc(ns*sizeof(void *), GFP_KERNEL);
1501                 if (!new_ee_hash) {
1502                         retcode = ERR_NOMEM;
1503                         goto fail;
1504                 }
1505         }
1506
1507         ((char *)new_conf->shared_secret)[SHARED_SECRET_MAX-1] = 0;
1508
1509         if (integrity_w_tfm) {
1510                 i = crypto_hash_digestsize(integrity_w_tfm);
1511                 int_dig_out = kmalloc(i, GFP_KERNEL);
1512                 if (!int_dig_out) {
1513                         retcode = ERR_NOMEM;
1514                         goto fail;
1515                 }
1516                 int_dig_in = kmalloc(i, GFP_KERNEL);
1517                 if (!int_dig_in) {
1518                         retcode = ERR_NOMEM;
1519                         goto fail;
1520                 }
1521                 int_dig_vv = kmalloc(i, GFP_KERNEL);
1522                 if (!int_dig_vv) {
1523                         retcode = ERR_NOMEM;
1524                         goto fail;
1525                 }
1526         }
1527
1528         if (!mdev->bitmap) {
1529                 if(drbd_bm_init(mdev)) {
1530                         retcode = ERR_NOMEM;
1531                         goto fail;
1532                 }
1533         }
1534
1535         drbd_flush_workqueue(mdev);
1536         spin_lock_irq(&mdev->req_lock);
1537         if (mdev->net_conf != NULL) {
1538                 retcode = ERR_NET_CONFIGURED;
1539                 spin_unlock_irq(&mdev->req_lock);
1540                 goto fail;
1541         }
1542         mdev->net_conf = new_conf;
1543
1544         mdev->send_cnt = 0;
1545         mdev->recv_cnt = 0;
1546
1547         if (new_tl_hash) {
1548                 kfree(mdev->tl_hash);
1549                 mdev->tl_hash_s = mdev->net_conf->max_epoch_size/8;
1550                 mdev->tl_hash = new_tl_hash;
1551         }
1552
1553         if (new_ee_hash) {
1554                 kfree(mdev->ee_hash);
1555                 mdev->ee_hash_s = mdev->net_conf->max_buffers/8;
1556                 mdev->ee_hash = new_ee_hash;
1557         }
1558
1559         crypto_free_hash(mdev->cram_hmac_tfm);
1560         mdev->cram_hmac_tfm = tfm;
1561
1562         crypto_free_hash(mdev->integrity_w_tfm);
1563         mdev->integrity_w_tfm = integrity_w_tfm;
1564
1565         crypto_free_hash(mdev->integrity_r_tfm);
1566         mdev->integrity_r_tfm = integrity_r_tfm;
1567
1568         kfree(mdev->int_dig_out);
1569         kfree(mdev->int_dig_in);
1570         kfree(mdev->int_dig_vv);
1571         mdev->int_dig_out=int_dig_out;
1572         mdev->int_dig_in=int_dig_in;
1573         mdev->int_dig_vv=int_dig_vv;
1574         retcode = _drbd_set_state(_NS(mdev, conn, C_UNCONNECTED), CS_VERBOSE, NULL);
1575         spin_unlock_irq(&mdev->req_lock);
1576
1577         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1578         reply->ret_code = retcode;
1579         drbd_reconfig_done(mdev);
1580         return 0;
1581
1582 fail:
1583         kfree(int_dig_out);
1584         kfree(int_dig_in);
1585         kfree(int_dig_vv);
1586         crypto_free_hash(tfm);
1587         crypto_free_hash(integrity_w_tfm);
1588         crypto_free_hash(integrity_r_tfm);
1589         kfree(new_tl_hash);
1590         kfree(new_ee_hash);
1591         kfree(new_conf);
1592
1593         reply->ret_code = retcode;
1594         drbd_reconfig_done(mdev);
1595         return 0;
1596 }
1597
1598 static int drbd_nl_disconnect(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1599                               struct drbd_nl_cfg_reply *reply)
1600 {
1601         int retcode;
1602         struct disconnect dc;
1603
1604         memset(&dc, 0, sizeof(struct disconnect));
1605         if (!disconnect_from_tags(mdev, nlp->tag_list, &dc)) {
1606                 retcode = ERR_MANDATORY_TAG;
1607                 goto fail;
1608         }
1609
1610         if (dc.force) {
1611                 spin_lock_irq(&mdev->req_lock);
1612                 if (mdev->state.conn >= C_WF_CONNECTION)
1613                         _drbd_set_state(_NS(mdev, conn, C_DISCONNECTING), CS_HARD, NULL);
1614                 spin_unlock_irq(&mdev->req_lock);
1615                 goto done;
1616         }
1617
1618         retcode = _drbd_request_state(mdev, NS(conn, C_DISCONNECTING), CS_ORDERED);
1619
1620         if (retcode == SS_NOTHING_TO_DO)
1621                 goto done;
1622         else if (retcode == SS_ALREADY_STANDALONE)
1623                 goto done;
1624         else if (retcode == SS_PRIMARY_NOP) {
1625                 /* Our statche checking code wants to see the peer outdated. */
1626                 retcode = drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1627                                                       pdsk, D_OUTDATED));
1628         } else if (retcode == SS_CW_FAILED_BY_PEER) {
1629                 /* The peer probably wants to see us outdated. */
1630                 retcode = _drbd_request_state(mdev, NS2(conn, C_DISCONNECTING,
1631                                                         disk, D_OUTDATED),
1632                                               CS_ORDERED);
1633                 if (retcode == SS_IS_DISKLESS || retcode == SS_LOWER_THAN_OUTDATED) {
1634                         drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
1635                         retcode = SS_SUCCESS;
1636                 }
1637         }
1638
1639         if (retcode < SS_SUCCESS)
1640                 goto fail;
1641
1642         if (wait_event_interruptible(mdev->state_wait,
1643                                      mdev->state.conn != C_DISCONNECTING)) {
1644                 /* Do not test for mdev->state.conn == C_STANDALONE, since
1645                    someone else might connect us in the mean time! */
1646                 retcode = ERR_INTR;
1647                 goto fail;
1648         }
1649
1650  done:
1651         retcode = NO_ERROR;
1652  fail:
1653         drbd_md_sync(mdev);
1654         reply->ret_code = retcode;
1655         return 0;
1656 }
1657
1658 void resync_after_online_grow(struct drbd_conf *mdev)
1659 {
1660         int iass; /* I am sync source */
1661
1662         dev_info(DEV, "Resync of new storage after online grow\n");
1663         if (mdev->state.role != mdev->state.peer)
1664                 iass = (mdev->state.role == R_PRIMARY);
1665         else
1666                 iass = test_bit(DISCARD_CONCURRENT, &mdev->flags);
1667
1668         if (iass)
1669                 drbd_start_resync(mdev, C_SYNC_SOURCE);
1670         else
1671                 _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE + CS_SERIALIZE);
1672 }
1673
1674 static int drbd_nl_resize(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1675                           struct drbd_nl_cfg_reply *reply)
1676 {
1677         struct resize rs;
1678         int retcode = NO_ERROR;
1679         enum determine_dev_size dd;
1680         enum dds_flags ddsf;
1681
1682         memset(&rs, 0, sizeof(struct resize));
1683         if (!resize_from_tags(mdev, nlp->tag_list, &rs)) {
1684                 retcode = ERR_MANDATORY_TAG;
1685                 goto fail;
1686         }
1687
1688         if (mdev->state.conn > C_CONNECTED) {
1689                 retcode = ERR_RESIZE_RESYNC;
1690                 goto fail;
1691         }
1692
1693         if (mdev->state.role == R_SECONDARY &&
1694             mdev->state.peer == R_SECONDARY) {
1695                 retcode = ERR_NO_PRIMARY;
1696                 goto fail;
1697         }
1698
1699         if (!get_ldev(mdev)) {
1700                 retcode = ERR_NO_DISK;
1701                 goto fail;
1702         }
1703
1704         if (rs.no_resync && mdev->agreed_pro_version < 93) {
1705                 retcode = ERR_NEED_APV_93;
1706                 goto fail;
1707         }
1708
1709         if (mdev->ldev->known_size != drbd_get_capacity(mdev->ldev->backing_bdev))
1710                 mdev->ldev->known_size = drbd_get_capacity(mdev->ldev->backing_bdev);
1711
1712         mdev->ldev->dc.disk_size = (sector_t)rs.resize_size;
1713         ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
1714         dd = drbd_determin_dev_size(mdev, ddsf);
1715         drbd_md_sync(mdev);
1716         put_ldev(mdev);
1717         if (dd == dev_size_error) {
1718                 retcode = ERR_NOMEM_BITMAP;
1719                 goto fail;
1720         }
1721
1722         if (mdev->state.conn == C_CONNECTED) {
1723                 if (dd == grew)
1724                         set_bit(RESIZE_PENDING, &mdev->flags);
1725
1726                 drbd_send_uuids(mdev);
1727                 drbd_send_sizes(mdev, 1, ddsf);
1728         }
1729
1730  fail:
1731         reply->ret_code = retcode;
1732         return 0;
1733 }
1734
1735 static int drbd_nl_syncer_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1736                                struct drbd_nl_cfg_reply *reply)
1737 {
1738         int retcode = NO_ERROR;
1739         int err;
1740         int ovr; /* online verify running */
1741         int rsr; /* re-sync running */
1742         struct crypto_hash *verify_tfm = NULL;
1743         struct crypto_hash *csums_tfm = NULL;
1744         struct syncer_conf sc;
1745         cpumask_var_t new_cpu_mask;
1746         int *rs_plan_s = NULL;
1747         int fifo_size;
1748
1749         if (!zalloc_cpumask_var(&new_cpu_mask, GFP_KERNEL)) {
1750                 retcode = ERR_NOMEM;
1751                 goto fail;
1752         }
1753
1754         if (nlp->flags & DRBD_NL_SET_DEFAULTS) {
1755                 memset(&sc, 0, sizeof(struct syncer_conf));
1756                 sc.rate       = DRBD_RATE_DEF;
1757                 sc.after      = DRBD_AFTER_DEF;
1758                 sc.al_extents = DRBD_AL_EXTENTS_DEF;
1759                 sc.on_no_data  = DRBD_ON_NO_DATA_DEF;
1760                 sc.c_plan_ahead = DRBD_C_PLAN_AHEAD_DEF;
1761                 sc.c_delay_target = DRBD_C_DELAY_TARGET_DEF;
1762                 sc.c_fill_target = DRBD_C_FILL_TARGET_DEF;
1763                 sc.c_max_rate = DRBD_C_MAX_RATE_DEF;
1764                 sc.c_min_rate = DRBD_C_MIN_RATE_DEF;
1765         } else
1766                 memcpy(&sc, &mdev->sync_conf, sizeof(struct syncer_conf));
1767
1768         if (!syncer_conf_from_tags(mdev, nlp->tag_list, &sc)) {
1769                 retcode = ERR_MANDATORY_TAG;
1770                 goto fail;
1771         }
1772
1773         /* re-sync running */
1774         rsr = ( mdev->state.conn == C_SYNC_SOURCE ||
1775                 mdev->state.conn == C_SYNC_TARGET ||
1776                 mdev->state.conn == C_PAUSED_SYNC_S ||
1777                 mdev->state.conn == C_PAUSED_SYNC_T );
1778
1779         if (rsr && strcmp(sc.csums_alg, mdev->sync_conf.csums_alg)) {
1780                 retcode = ERR_CSUMS_RESYNC_RUNNING;
1781                 goto fail;
1782         }
1783
1784         if (!rsr && sc.csums_alg[0]) {
1785                 csums_tfm = crypto_alloc_hash(sc.csums_alg, 0, CRYPTO_ALG_ASYNC);
1786                 if (IS_ERR(csums_tfm)) {
1787                         csums_tfm = NULL;
1788                         retcode = ERR_CSUMS_ALG;
1789                         goto fail;
1790                 }
1791
1792                 if (!drbd_crypto_is_hash(crypto_hash_tfm(csums_tfm))) {
1793                         retcode = ERR_CSUMS_ALG_ND;
1794                         goto fail;
1795                 }
1796         }
1797
1798         /* online verify running */
1799         ovr = (mdev->state.conn == C_VERIFY_S || mdev->state.conn == C_VERIFY_T);
1800
1801         if (ovr) {
1802                 if (strcmp(sc.verify_alg, mdev->sync_conf.verify_alg)) {
1803                         retcode = ERR_VERIFY_RUNNING;
1804                         goto fail;
1805                 }
1806         }
1807
1808         if (!ovr && sc.verify_alg[0]) {
1809                 verify_tfm = crypto_alloc_hash(sc.verify_alg, 0, CRYPTO_ALG_ASYNC);
1810                 if (IS_ERR(verify_tfm)) {
1811                         verify_tfm = NULL;
1812                         retcode = ERR_VERIFY_ALG;
1813                         goto fail;
1814                 }
1815
1816                 if (!drbd_crypto_is_hash(crypto_hash_tfm(verify_tfm))) {
1817                         retcode = ERR_VERIFY_ALG_ND;
1818                         goto fail;
1819                 }
1820         }
1821
1822         /* silently ignore cpu mask on UP kernel */
1823         if (nr_cpu_ids > 1 && sc.cpu_mask[0] != 0) {
1824                 err = __bitmap_parse(sc.cpu_mask, 32, 0,
1825                                 cpumask_bits(new_cpu_mask), nr_cpu_ids);
1826                 if (err) {
1827                         dev_warn(DEV, "__bitmap_parse() failed with %d\n", err);
1828                         retcode = ERR_CPU_MASK_PARSE;
1829                         goto fail;
1830                 }
1831         }
1832
1833         ERR_IF (sc.rate < 1) sc.rate = 1;
1834         ERR_IF (sc.al_extents < 7) sc.al_extents = 127; /* arbitrary minimum */
1835 #define AL_MAX ((MD_AL_MAX_SIZE-1) * AL_EXTENTS_PT)
1836         if (sc.al_extents > AL_MAX) {
1837                 dev_err(DEV, "sc.al_extents > %d\n", AL_MAX);
1838                 sc.al_extents = AL_MAX;
1839         }
1840 #undef AL_MAX
1841
1842         /* to avoid spurious errors when configuring minors before configuring
1843          * the minors they depend on: if necessary, first create the minor we
1844          * depend on */
1845         if (sc.after >= 0)
1846                 ensure_mdev(sc.after, 1);
1847
1848         /* most sanity checks done, try to assign the new sync-after
1849          * dependency.  need to hold the global lock in there,
1850          * to avoid a race in the dependency loop check. */
1851         retcode = drbd_alter_sa(mdev, sc.after);
1852         if (retcode != NO_ERROR)
1853                 goto fail;
1854
1855         fifo_size = (sc.c_plan_ahead * 10 * SLEEP_TIME) / HZ;
1856         if (fifo_size != mdev->rs_plan_s.size && fifo_size > 0) {
1857                 rs_plan_s   = kzalloc(sizeof(int) * fifo_size, GFP_KERNEL);
1858                 if (!rs_plan_s) {
1859                         dev_err(DEV, "kmalloc of fifo_buffer failed");
1860                         retcode = ERR_NOMEM;
1861                         goto fail;
1862                 }
1863         }
1864
1865         /* ok, assign the rest of it as well.
1866          * lock against receive_SyncParam() */
1867         spin_lock(&mdev->peer_seq_lock);
1868         mdev->sync_conf = sc;
1869
1870         if (!rsr) {
1871                 crypto_free_hash(mdev->csums_tfm);
1872                 mdev->csums_tfm = csums_tfm;
1873                 csums_tfm = NULL;
1874         }
1875
1876         if (!ovr) {
1877                 crypto_free_hash(mdev->verify_tfm);
1878                 mdev->verify_tfm = verify_tfm;
1879                 verify_tfm = NULL;
1880         }
1881
1882         if (fifo_size != mdev->rs_plan_s.size) {
1883                 kfree(mdev->rs_plan_s.values);
1884                 mdev->rs_plan_s.values = rs_plan_s;
1885                 mdev->rs_plan_s.size   = fifo_size;
1886                 mdev->rs_planed = 0;
1887                 rs_plan_s = NULL;
1888         }
1889
1890         spin_unlock(&mdev->peer_seq_lock);
1891
1892         if (get_ldev(mdev)) {
1893                 wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
1894                 drbd_al_shrink(mdev);
1895                 err = drbd_check_al_size(mdev);
1896                 lc_unlock(mdev->act_log);
1897                 wake_up(&mdev->al_wait);
1898
1899                 put_ldev(mdev);
1900                 drbd_md_sync(mdev);
1901
1902                 if (err) {
1903                         retcode = ERR_NOMEM;
1904                         goto fail;
1905                 }
1906         }
1907
1908         if (mdev->state.conn >= C_CONNECTED)
1909                 drbd_send_sync_param(mdev, &sc);
1910
1911         if (!cpumask_equal(mdev->cpu_mask, new_cpu_mask)) {
1912                 cpumask_copy(mdev->cpu_mask, new_cpu_mask);
1913                 drbd_calc_cpu_mask(mdev);
1914                 mdev->receiver.reset_cpu_mask = 1;
1915                 mdev->asender.reset_cpu_mask = 1;
1916                 mdev->worker.reset_cpu_mask = 1;
1917         }
1918
1919         kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE);
1920 fail:
1921         kfree(rs_plan_s);
1922         free_cpumask_var(new_cpu_mask);
1923         crypto_free_hash(csums_tfm);
1924         crypto_free_hash(verify_tfm);
1925         reply->ret_code = retcode;
1926         return 0;
1927 }
1928
1929 static int drbd_nl_invalidate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1930                               struct drbd_nl_cfg_reply *reply)
1931 {
1932         int retcode;
1933
1934         /* If there is still bitmap IO pending, probably because of a previous
1935          * resync just being finished, wait for it before requesting a new resync. */
1936         wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
1937
1938         retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T), CS_ORDERED);
1939
1940         if (retcode < SS_SUCCESS && retcode != SS_NEED_CONNECTION)
1941                 retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1942
1943         while (retcode == SS_NEED_CONNECTION) {
1944                 spin_lock_irq(&mdev->req_lock);
1945                 if (mdev->state.conn < C_CONNECTED)
1946                         retcode = _drbd_set_state(_NS(mdev, disk, D_INCONSISTENT), CS_VERBOSE, NULL);
1947                 spin_unlock_irq(&mdev->req_lock);
1948
1949                 if (retcode != SS_NEED_CONNECTION)
1950                         break;
1951
1952                 retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T));
1953         }
1954
1955         reply->ret_code = retcode;
1956         return 0;
1957 }
1958
1959 static int drbd_bmio_set_susp_al(struct drbd_conf *mdev)
1960 {
1961         int rv;
1962
1963         rv = drbd_bmio_set_n_write(mdev);
1964         drbd_suspend_al(mdev);
1965         return rv;
1966 }
1967
1968 static int drbd_nl_invalidate_peer(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1969                                    struct drbd_nl_cfg_reply *reply)
1970 {
1971         int retcode;
1972
1973         /* If there is still bitmap IO pending, probably because of a previous
1974          * resync just being finished, wait for it before requesting a new resync. */
1975         wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
1976
1977         retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S), CS_ORDERED);
1978
1979         if (retcode < SS_SUCCESS) {
1980                 if (retcode == SS_NEED_CONNECTION && mdev->state.role == R_PRIMARY) {
1981                         /* The peer will get a resync upon connect anyways. Just make that
1982                            into a full resync. */
1983                         retcode = drbd_request_state(mdev, NS(pdsk, D_INCONSISTENT));
1984                         if (retcode >= SS_SUCCESS) {
1985                                 if (drbd_bitmap_io(mdev, &drbd_bmio_set_susp_al,
1986                                         "set_n_write from invalidate_peer",
1987                                         BM_LOCKED_SET_ALLOWED))
1988                                         retcode = ERR_IO_MD_DISK;
1989                         }
1990                 } else
1991                         retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S));
1992         }
1993
1994         reply->ret_code = retcode;
1995         return 0;
1996 }
1997
1998 static int drbd_nl_pause_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
1999                               struct drbd_nl_cfg_reply *reply)
2000 {
2001         int retcode = NO_ERROR;
2002
2003         if (drbd_request_state(mdev, NS(user_isp, 1)) == SS_NOTHING_TO_DO)
2004                 retcode = ERR_PAUSE_IS_SET;
2005
2006         reply->ret_code = retcode;
2007         return 0;
2008 }
2009
2010 static int drbd_nl_resume_sync(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2011                                struct drbd_nl_cfg_reply *reply)
2012 {
2013         int retcode = NO_ERROR;
2014         union drbd_state s;
2015
2016         if (drbd_request_state(mdev, NS(user_isp, 0)) == SS_NOTHING_TO_DO) {
2017                 s = mdev->state;
2018                 if (s.conn == C_PAUSED_SYNC_S || s.conn == C_PAUSED_SYNC_T) {
2019                         retcode = s.aftr_isp ? ERR_PIC_AFTER_DEP :
2020                                   s.peer_isp ? ERR_PIC_PEER_DEP : ERR_PAUSE_IS_CLEAR;
2021                 } else {
2022                         retcode = ERR_PAUSE_IS_CLEAR;
2023                 }
2024         }
2025
2026         reply->ret_code = retcode;
2027         return 0;
2028 }
2029
2030 static int drbd_nl_suspend_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2031                               struct drbd_nl_cfg_reply *reply)
2032 {
2033         reply->ret_code = drbd_request_state(mdev, NS(susp, 1));
2034
2035         return 0;
2036 }
2037
2038 static int drbd_nl_resume_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2039                              struct drbd_nl_cfg_reply *reply)
2040 {
2041         if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
2042                 drbd_uuid_new_current(mdev);
2043                 clear_bit(NEW_CUR_UUID, &mdev->flags);
2044         }
2045         drbd_suspend_io(mdev);
2046         reply->ret_code = drbd_request_state(mdev, NS3(susp, 0, susp_nod, 0, susp_fen, 0));
2047         if (reply->ret_code == SS_SUCCESS) {
2048                 if (mdev->state.conn < C_CONNECTED)
2049                         tl_clear(mdev);
2050                 if (mdev->state.disk == D_DISKLESS || mdev->state.disk == D_FAILED)
2051                         tl_restart(mdev, fail_frozen_disk_io);
2052         }
2053         drbd_resume_io(mdev);
2054
2055         return 0;
2056 }
2057
2058 static int drbd_nl_outdate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2059                            struct drbd_nl_cfg_reply *reply)
2060 {
2061         reply->ret_code = drbd_request_state(mdev, NS(disk, D_OUTDATED));
2062         return 0;
2063 }
2064
2065 static int drbd_nl_get_config(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2066                            struct drbd_nl_cfg_reply *reply)
2067 {
2068         unsigned short *tl;
2069
2070         tl = reply->tag_list;
2071
2072         if (get_ldev(mdev)) {
2073                 tl = disk_conf_to_tags(mdev, &mdev->ldev->dc, tl);
2074                 put_ldev(mdev);
2075         }
2076
2077         if (get_net_conf(mdev)) {
2078                 tl = net_conf_to_tags(mdev, mdev->net_conf, tl);
2079                 put_net_conf(mdev);
2080         }
2081         tl = syncer_conf_to_tags(mdev, &mdev->sync_conf, tl);
2082
2083         put_unaligned(TT_END, tl++); /* Close the tag list */
2084
2085         return (int)((char *)tl - (char *)reply->tag_list);
2086 }
2087
2088 static int drbd_nl_get_state(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2089                              struct drbd_nl_cfg_reply *reply)
2090 {
2091         unsigned short *tl = reply->tag_list;
2092         union drbd_state s = mdev->state;
2093         unsigned long rs_left;
2094         unsigned int res;
2095
2096         tl = get_state_to_tags(mdev, (struct get_state *)&s, tl);
2097
2098         /* no local ref, no bitmap, no syncer progress. */
2099         if (s.conn >= C_SYNC_SOURCE && s.conn <= C_PAUSED_SYNC_T) {
2100                 if (get_ldev(mdev)) {
2101                         drbd_get_syncer_progress(mdev, &rs_left, &res);
2102                         tl = tl_add_int(tl, T_sync_progress, &res);
2103                         put_ldev(mdev);
2104                 }
2105         }
2106         put_unaligned(TT_END, tl++); /* Close the tag list */
2107
2108         return (int)((char *)tl - (char *)reply->tag_list);
2109 }
2110
2111 static int drbd_nl_get_uuids(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2112                              struct drbd_nl_cfg_reply *reply)
2113 {
2114         unsigned short *tl;
2115
2116         tl = reply->tag_list;
2117
2118         if (get_ldev(mdev)) {
2119                 tl = tl_add_blob(tl, T_uuids, mdev->ldev->md.uuid, UI_SIZE*sizeof(u64));
2120                 tl = tl_add_int(tl, T_uuids_flags, &mdev->ldev->md.flags);
2121                 put_ldev(mdev);
2122         }
2123         put_unaligned(TT_END, tl++); /* Close the tag list */
2124
2125         return (int)((char *)tl - (char *)reply->tag_list);
2126 }
2127
2128 /**
2129  * drbd_nl_get_timeout_flag() - Used by drbdsetup to find out which timeout value to use
2130  * @mdev:       DRBD device.
2131  * @nlp:        Netlink/connector packet from drbdsetup
2132  * @reply:      Reply packet for drbdsetup
2133  */
2134 static int drbd_nl_get_timeout_flag(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2135                                     struct drbd_nl_cfg_reply *reply)
2136 {
2137         unsigned short *tl;
2138         char rv;
2139
2140         tl = reply->tag_list;
2141
2142         rv = mdev->state.pdsk == D_OUTDATED        ? UT_PEER_OUTDATED :
2143           test_bit(USE_DEGR_WFC_T, &mdev->flags) ? UT_DEGRADED : UT_DEFAULT;
2144
2145         tl = tl_add_blob(tl, T_use_degraded, &rv, sizeof(rv));
2146         put_unaligned(TT_END, tl++); /* Close the tag list */
2147
2148         return (int)((char *)tl - (char *)reply->tag_list);
2149 }
2150
2151 static int drbd_nl_start_ov(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2152                                     struct drbd_nl_cfg_reply *reply)
2153 {
2154         /* default to resume from last known position, if possible */
2155         struct start_ov args =
2156                 { .start_sector = mdev->ov_start_sector };
2157
2158         if (!start_ov_from_tags(mdev, nlp->tag_list, &args)) {
2159                 reply->ret_code = ERR_MANDATORY_TAG;
2160                 return 0;
2161         }
2162
2163         /* If there is still bitmap IO pending, e.g. previous resync or verify
2164          * just being finished, wait for it before requesting a new resync. */
2165         wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
2166
2167         /* w_make_ov_request expects position to be aligned */
2168         mdev->ov_start_sector = args.start_sector & ~BM_SECT_PER_BIT;
2169         reply->ret_code = drbd_request_state(mdev,NS(conn,C_VERIFY_S));
2170         return 0;
2171 }
2172
2173
2174 static int drbd_nl_new_c_uuid(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
2175                               struct drbd_nl_cfg_reply *reply)
2176 {
2177         int retcode = NO_ERROR;
2178         int skip_initial_sync = 0;
2179         int err;
2180
2181         struct new_c_uuid args;
2182
2183         memset(&args, 0, sizeof(struct new_c_uuid));
2184         if (!new_c_uuid_from_tags(mdev, nlp->tag_list, &args)) {
2185                 reply->ret_code = ERR_MANDATORY_TAG;
2186                 return 0;
2187         }
2188
2189         mutex_lock(&mdev->state_mutex); /* Protects us against serialized state changes. */
2190
2191         if (!get_ldev(mdev)) {
2192                 retcode = ERR_NO_DISK;
2193                 goto out;
2194         }
2195
2196         /* this is "skip initial sync", assume to be clean */
2197         if (mdev->state.conn == C_CONNECTED && mdev->agreed_pro_version >= 90 &&
2198             mdev->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED && args.clear_bm) {
2199                 dev_info(DEV, "Preparing to skip initial sync\n");
2200                 skip_initial_sync = 1;
2201         } else if (mdev->state.conn != C_STANDALONE) {
2202                 retcode = ERR_CONNECTED;
2203                 goto out_dec;
2204         }
2205
2206         drbd_uuid_set(mdev, UI_BITMAP, 0); /* Rotate UI_BITMAP to History 1, etc... */
2207         drbd_uuid_new_current(mdev); /* New current, previous to UI_BITMAP */
2208
2209         if (args.clear_bm) {
2210                 err = drbd_bitmap_io(mdev, &drbd_bmio_clear_n_write,
2211                         "clear_n_write from new_c_uuid", BM_LOCKED_MASK);
2212                 if (err) {
2213                         dev_err(DEV, "Writing bitmap failed with %d\n",err);
2214                         retcode = ERR_IO_MD_DISK;
2215                 }
2216                 if (skip_initial_sync) {
2217                         drbd_send_uuids_skip_initial_sync(mdev);
2218                         _drbd_uuid_set(mdev, UI_BITMAP, 0);
2219                         drbd_print_uuids(mdev, "cleared bitmap UUID");
2220                         spin_lock_irq(&mdev->req_lock);
2221                         _drbd_set_state(_NS2(mdev, disk, D_UP_TO_DATE, pdsk, D_UP_TO_DATE),
2222                                         CS_VERBOSE, NULL);
2223                         spin_unlock_irq(&mdev->req_lock);
2224                 }
2225         }
2226
2227         drbd_md_sync(mdev);
2228 out_dec:
2229         put_ldev(mdev);
2230 out:
2231         mutex_unlock(&mdev->state_mutex);
2232
2233         reply->ret_code = retcode;
2234         return 0;
2235 }
2236
2237 struct cn_handler_struct {
2238         int (*function)(struct drbd_conf *,
2239                          struct drbd_nl_cfg_req *,
2240                          struct drbd_nl_cfg_reply *);
2241         int reply_body_size;
2242 };
2243
2244 static struct cn_handler_struct cnd_table[] = {
2245         [ P_primary ]           = { &drbd_nl_primary,           0 },
2246         [ P_secondary ]         = { &drbd_nl_secondary,         0 },
2247         [ P_disk_conf ]         = { &drbd_nl_disk_conf,         0 },
2248         [ P_detach ]            = { &drbd_nl_detach,            0 },
2249         [ P_net_conf ]          = { &drbd_nl_net_conf,          0 },
2250         [ P_disconnect ]        = { &drbd_nl_disconnect,        0 },
2251         [ P_resize ]            = { &drbd_nl_resize,            0 },
2252         [ P_syncer_conf ]       = { &drbd_nl_syncer_conf,       0 },
2253         [ P_invalidate ]        = { &drbd_nl_invalidate,        0 },
2254         [ P_invalidate_peer ]   = { &drbd_nl_invalidate_peer,   0 },
2255         [ P_pause_sync ]        = { &drbd_nl_pause_sync,        0 },
2256         [ P_resume_sync ]       = { &drbd_nl_resume_sync,       0 },
2257         [ P_suspend_io ]        = { &drbd_nl_suspend_io,        0 },
2258         [ P_resume_io ]         = { &drbd_nl_resume_io,         0 },
2259         [ P_outdate ]           = { &drbd_nl_outdate,           0 },
2260         [ P_get_config ]        = { &drbd_nl_get_config,
2261                                     sizeof(struct syncer_conf_tag_len_struct) +
2262                                     sizeof(struct disk_conf_tag_len_struct) +
2263                                     sizeof(struct net_conf_tag_len_struct) },
2264         [ P_get_state ]         = { &drbd_nl_get_state,
2265                                     sizeof(struct get_state_tag_len_struct) +
2266                                     sizeof(struct sync_progress_tag_len_struct) },
2267         [ P_get_uuids ]         = { &drbd_nl_get_uuids,
2268                                     sizeof(struct get_uuids_tag_len_struct) },
2269         [ P_get_timeout_flag ]  = { &drbd_nl_get_timeout_flag,
2270                                     sizeof(struct get_timeout_flag_tag_len_struct)},
2271         [ P_start_ov ]          = { &drbd_nl_start_ov,          0 },
2272         [ P_new_c_uuid ]        = { &drbd_nl_new_c_uuid,        0 },
2273 };
2274
2275 static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms *nsp)
2276 {
2277         struct drbd_nl_cfg_req *nlp = (struct drbd_nl_cfg_req *)req->data;
2278         struct cn_handler_struct *cm;
2279         struct cn_msg *cn_reply;
2280         struct drbd_nl_cfg_reply *reply;
2281         struct drbd_conf *mdev;
2282         int retcode, rr;
2283         int reply_size = sizeof(struct cn_msg)
2284                 + sizeof(struct drbd_nl_cfg_reply)
2285                 + sizeof(short int);
2286
2287         if (!try_module_get(THIS_MODULE)) {
2288                 printk(KERN_ERR "drbd: try_module_get() failed!\n");
2289                 return;
2290         }
2291
2292         if (!cap_raised(current_cap(), CAP_SYS_ADMIN)) {
2293                 retcode = ERR_PERM;
2294                 goto fail;
2295         }
2296
2297         mdev = ensure_mdev(nlp->drbd_minor,
2298                         (nlp->flags & DRBD_NL_CREATE_DEVICE));
2299         if (!mdev) {
2300                 retcode = ERR_MINOR_INVALID;
2301                 goto fail;
2302         }
2303
2304         if (nlp->packet_type >= P_nl_after_last_packet ||
2305             nlp->packet_type == P_return_code_only) {
2306                 retcode = ERR_PACKET_NR;
2307                 goto fail;
2308         }
2309
2310         cm = cnd_table + nlp->packet_type;
2311
2312         /* This may happen if packet number is 0: */
2313         if (cm->function == NULL) {
2314                 retcode = ERR_PACKET_NR;
2315                 goto fail;
2316         }
2317
2318         reply_size += cm->reply_body_size;
2319
2320         /* allocation not in the IO path, cqueue thread context */
2321         cn_reply = kzalloc(reply_size, GFP_KERNEL);
2322         if (!cn_reply) {
2323                 retcode = ERR_NOMEM;
2324                 goto fail;
2325         }
2326         reply = (struct drbd_nl_cfg_reply *) cn_reply->data;
2327
2328         reply->packet_type =
2329                 cm->reply_body_size ? nlp->packet_type : P_return_code_only;
2330         reply->minor = nlp->drbd_minor;
2331         reply->ret_code = NO_ERROR; /* Might by modified by cm->function. */
2332         /* reply->tag_list; might be modified by cm->function. */
2333
2334         rr = cm->function(mdev, nlp, reply);
2335
2336         cn_reply->id = req->id;
2337         cn_reply->seq = req->seq;
2338         cn_reply->ack = req->ack  + 1;
2339         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) + rr;
2340         cn_reply->flags = 0;
2341
2342         rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_KERNEL);
2343         if (rr && rr != -ESRCH)
2344                 printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2345
2346         kfree(cn_reply);
2347         module_put(THIS_MODULE);
2348         return;
2349  fail:
2350         drbd_nl_send_reply(req, retcode);
2351         module_put(THIS_MODULE);
2352 }
2353
2354 static atomic_t drbd_nl_seq = ATOMIC_INIT(2); /* two. */
2355
2356 static unsigned short *
2357 __tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data,
2358         unsigned short len, int nul_terminated)
2359 {
2360         unsigned short l = tag_descriptions[tag_number(tag)].max_len;
2361         len = (len < l) ? len :  l;
2362         put_unaligned(tag, tl++);
2363         put_unaligned(len, tl++);
2364         memcpy(tl, data, len);
2365         tl = (unsigned short*)((char*)tl + len);
2366         if (nul_terminated)
2367                 *((char*)tl - 1) = 0;
2368         return tl;
2369 }
2370
2371 static unsigned short *
2372 tl_add_blob(unsigned short *tl, enum drbd_tags tag, const void *data, int len)
2373 {
2374         return __tl_add_blob(tl, tag, data, len, 0);
2375 }
2376
2377 static unsigned short *
2378 tl_add_str(unsigned short *tl, enum drbd_tags tag, const char *str)
2379 {
2380         return __tl_add_blob(tl, tag, str, strlen(str)+1, 0);
2381 }
2382
2383 static unsigned short *
2384 tl_add_int(unsigned short *tl, enum drbd_tags tag, const void *val)
2385 {
2386         put_unaligned(tag, tl++);
2387         switch(tag_type(tag)) {
2388         case TT_INTEGER:
2389                 put_unaligned(sizeof(int), tl++);
2390                 put_unaligned(*(int *)val, (int *)tl);
2391                 tl = (unsigned short*)((char*)tl+sizeof(int));
2392                 break;
2393         case TT_INT64:
2394                 put_unaligned(sizeof(u64), tl++);
2395                 put_unaligned(*(u64 *)val, (u64 *)tl);
2396                 tl = (unsigned short*)((char*)tl+sizeof(u64));
2397                 break;
2398         default:
2399                 /* someone did something stupid. */
2400                 ;
2401         }
2402         return tl;
2403 }
2404
2405 void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state state)
2406 {
2407         char buffer[sizeof(struct cn_msg)+
2408                     sizeof(struct drbd_nl_cfg_reply)+
2409                     sizeof(struct get_state_tag_len_struct)+
2410                     sizeof(short int)];
2411         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2412         struct drbd_nl_cfg_reply *reply =
2413                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2414         unsigned short *tl = reply->tag_list;
2415
2416         /* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2417
2418         tl = get_state_to_tags(mdev, (struct get_state *)&state, tl);
2419
2420         put_unaligned(TT_END, tl++); /* Close the tag list */
2421
2422         cn_reply->id.idx = CN_IDX_DRBD;
2423         cn_reply->id.val = CN_VAL_DRBD;
2424
2425         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2426         cn_reply->ack = 0; /* not used here. */
2427         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2428                 (int)((char *)tl - (char *)reply->tag_list);
2429         cn_reply->flags = 0;
2430
2431         reply->packet_type = P_get_state;
2432         reply->minor = mdev_to_minor(mdev);
2433         reply->ret_code = NO_ERROR;
2434
2435         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2436 }
2437
2438 void drbd_bcast_ev_helper(struct drbd_conf *mdev, char *helper_name)
2439 {
2440         char buffer[sizeof(struct cn_msg)+
2441                     sizeof(struct drbd_nl_cfg_reply)+
2442                     sizeof(struct call_helper_tag_len_struct)+
2443                     sizeof(short int)];
2444         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2445         struct drbd_nl_cfg_reply *reply =
2446                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2447         unsigned short *tl = reply->tag_list;
2448
2449         /* dev_warn(DEV, "drbd_bcast_state() got called\n"); */
2450
2451         tl = tl_add_str(tl, T_helper, helper_name);
2452         put_unaligned(TT_END, tl++); /* Close the tag list */
2453
2454         cn_reply->id.idx = CN_IDX_DRBD;
2455         cn_reply->id.val = CN_VAL_DRBD;
2456
2457         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2458         cn_reply->ack = 0; /* not used here. */
2459         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2460                 (int)((char *)tl - (char *)reply->tag_list);
2461         cn_reply->flags = 0;
2462
2463         reply->packet_type = P_call_helper;
2464         reply->minor = mdev_to_minor(mdev);
2465         reply->ret_code = NO_ERROR;
2466
2467         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2468 }
2469
2470 void drbd_bcast_ee(struct drbd_conf *mdev,
2471                 const char *reason, const int dgs,
2472                 const char* seen_hash, const char* calc_hash,
2473                 const struct drbd_epoch_entry* e)
2474 {
2475         struct cn_msg *cn_reply;
2476         struct drbd_nl_cfg_reply *reply;
2477         unsigned short *tl;
2478         struct page *page;
2479         unsigned len;
2480
2481         if (!e)
2482                 return;
2483         if (!reason || !reason[0])
2484                 return;
2485
2486         /* apparently we have to memcpy twice, first to prepare the data for the
2487          * struct cn_msg, then within cn_netlink_send from the cn_msg to the
2488          * netlink skb. */
2489         /* receiver thread context, which is not in the writeout path (of this node),
2490          * but may be in the writeout path of the _other_ node.
2491          * GFP_NOIO to avoid potential "distributed deadlock". */
2492         cn_reply = kzalloc(
2493                 sizeof(struct cn_msg)+
2494                 sizeof(struct drbd_nl_cfg_reply)+
2495                 sizeof(struct dump_ee_tag_len_struct)+
2496                 sizeof(short int),
2497                 GFP_NOIO);
2498
2499         if (!cn_reply) {
2500                 dev_err(DEV, "could not kmalloc buffer for drbd_bcast_ee, sector %llu, size %u\n",
2501                                 (unsigned long long)e->sector, e->size);
2502                 return;
2503         }
2504
2505         reply = (struct drbd_nl_cfg_reply*)cn_reply->data;
2506         tl = reply->tag_list;
2507
2508         tl = tl_add_str(tl, T_dump_ee_reason, reason);
2509         tl = tl_add_blob(tl, T_seen_digest, seen_hash, dgs);
2510         tl = tl_add_blob(tl, T_calc_digest, calc_hash, dgs);
2511         tl = tl_add_int(tl, T_ee_sector, &e->sector);
2512         tl = tl_add_int(tl, T_ee_block_id, &e->block_id);
2513
2514         /* dump the first 32k */
2515         len = min_t(unsigned, e->size, 32 << 10);
2516         put_unaligned(T_ee_data, tl++);
2517         put_unaligned(len, tl++);
2518
2519         page = e->pages;
2520         page_chain_for_each(page) {
2521                 void *d = kmap_atomic(page, KM_USER0);
2522                 unsigned l = min_t(unsigned, len, PAGE_SIZE);
2523                 memcpy(tl, d, l);
2524                 kunmap_atomic(d, KM_USER0);
2525                 tl = (unsigned short*)((char*)tl + l);
2526                 len -= l;
2527                 if (len == 0)
2528                         break;
2529         }
2530         put_unaligned(TT_END, tl++); /* Close the tag list */
2531
2532         cn_reply->id.idx = CN_IDX_DRBD;
2533         cn_reply->id.val = CN_VAL_DRBD;
2534
2535         cn_reply->seq = atomic_add_return(1,&drbd_nl_seq);
2536         cn_reply->ack = 0; // not used here.
2537         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2538                 (int)((char*)tl - (char*)reply->tag_list);
2539         cn_reply->flags = 0;
2540
2541         reply->packet_type = P_dump_ee;
2542         reply->minor = mdev_to_minor(mdev);
2543         reply->ret_code = NO_ERROR;
2544
2545         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2546         kfree(cn_reply);
2547 }
2548
2549 void drbd_bcast_sync_progress(struct drbd_conf *mdev)
2550 {
2551         char buffer[sizeof(struct cn_msg)+
2552                     sizeof(struct drbd_nl_cfg_reply)+
2553                     sizeof(struct sync_progress_tag_len_struct)+
2554                     sizeof(short int)];
2555         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2556         struct drbd_nl_cfg_reply *reply =
2557                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2558         unsigned short *tl = reply->tag_list;
2559         unsigned long rs_left;
2560         unsigned int res;
2561
2562         /* no local ref, no bitmap, no syncer progress, no broadcast. */
2563         if (!get_ldev(mdev))
2564                 return;
2565         drbd_get_syncer_progress(mdev, &rs_left, &res);
2566         put_ldev(mdev);
2567
2568         tl = tl_add_int(tl, T_sync_progress, &res);
2569         put_unaligned(TT_END, tl++); /* Close the tag list */
2570
2571         cn_reply->id.idx = CN_IDX_DRBD;
2572         cn_reply->id.val = CN_VAL_DRBD;
2573
2574         cn_reply->seq = atomic_add_return(1, &drbd_nl_seq);
2575         cn_reply->ack = 0; /* not used here. */
2576         cn_reply->len = sizeof(struct drbd_nl_cfg_reply) +
2577                 (int)((char *)tl - (char *)reply->tag_list);
2578         cn_reply->flags = 0;
2579
2580         reply->packet_type = P_sync_progress;
2581         reply->minor = mdev_to_minor(mdev);
2582         reply->ret_code = NO_ERROR;
2583
2584         cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2585 }
2586
2587 int __init drbd_nl_init(void)
2588 {
2589         static struct cb_id cn_id_drbd;
2590         int err, try=10;
2591
2592         cn_id_drbd.val = CN_VAL_DRBD;
2593         do {
2594                 cn_id_drbd.idx = cn_idx;
2595                 err = cn_add_callback(&cn_id_drbd, "cn_drbd", &drbd_connector_callback);
2596                 if (!err)
2597                         break;
2598                 cn_idx = (cn_idx + CN_IDX_STEP);
2599         } while (try--);
2600
2601         if (err) {
2602                 printk(KERN_ERR "drbd: cn_drbd failed to register\n");
2603                 return err;
2604         }
2605
2606         return 0;
2607 }
2608
2609 void drbd_nl_cleanup(void)
2610 {
2611         static struct cb_id cn_id_drbd;
2612
2613         cn_id_drbd.idx = cn_idx;
2614         cn_id_drbd.val = CN_VAL_DRBD;
2615
2616         cn_del_callback(&cn_id_drbd);
2617 }
2618
2619 void drbd_nl_send_reply(struct cn_msg *req, int ret_code)
2620 {
2621         char buffer[sizeof(struct cn_msg)+sizeof(struct drbd_nl_cfg_reply)];
2622         struct cn_msg *cn_reply = (struct cn_msg *) buffer;
2623         struct drbd_nl_cfg_reply *reply =
2624                 (struct drbd_nl_cfg_reply *)cn_reply->data;
2625         int rr;
2626
2627         memset(buffer, 0, sizeof(buffer));
2628         cn_reply->id = req->id;
2629
2630         cn_reply->seq = req->seq;
2631         cn_reply->ack = req->ack  + 1;
2632         cn_reply->len = sizeof(struct drbd_nl_cfg_reply);
2633         cn_reply->flags = 0;
2634
2635         reply->packet_type = P_return_code_only;
2636         reply->minor = ((struct drbd_nl_cfg_req *)req->data)->drbd_minor;
2637         reply->ret_code = ret_code;
2638
2639         rr = cn_netlink_send(cn_reply, CN_IDX_DRBD, GFP_NOIO);
2640         if (rr && rr != -ESRCH)
2641                 printk(KERN_INFO "drbd: cn_netlink_send()=%d\n", rr);
2642 }
2643