fs/ocfs2/dlm/dlmconvert.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * dlmconvert.c
   4  *
   5  * underlying calls for lock conversion
   6  *
   7  * Copyright (C) 2004 Oracle.  All rights reserved.
   8  */
   9
  10
  11 #include <linux/module.h>
  12 #include <linux/fs.h>
  13 #include <linux/types.h>
  14 #include <linux/highmem.h>
  15 #include <linux/init.h>
  16 #include <linux/sysctl.h>
  17 #include <linux/random.h>
  18 #include <linux/blkdev.h>
  19 #include <linux/socket.h>
  20 #include <linux/inet.h>
  21 #include <linux/spinlock.h>
  22
  23
  24 #include "../cluster/heartbeat.h"
  25 #include "../cluster/nodemanager.h"
  26 #include "../cluster/tcp.h"
  27
  28 #include "dlmapi.h"
  29 #include "dlmcommon.h"
  30
  31 #include "dlmconvert.h"
  32
  33 #define MLOG_MASK_PREFIX ML_DLM
  34 #include "../cluster/masklog.h"
  35
  36 /* NOTE: __dlmconvert_master is the only function in here that
  37  * needs a spinlock held on entry (res->spinlock) and it is the
  38  * only one that holds a lock on exit (res->spinlock).
  39  * All other functions in here need no locks and drop all of
  40  * the locks that they acquire. */
  41 static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
  42                                            struct dlm_lock_resource *res,
  43                                            struct dlm_lock *lock, int flags,
  44                                            int type, int *call_ast,
  45                                            int *kick_thread);
  46 static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
  47                                            struct dlm_lock_resource *res,
  48                                            struct dlm_lock *lock, int flags, int type);
  49
  50 /*
  51  * this is only called directly by dlmlock(), and only when the
  52  * local node is the owner of the lockres
  53  * locking:
  54  *   caller needs:  none
  55  *   taken:         takes and drops res->spinlock
  56  *   held on exit:  none
  57  * returns: see __dlmconvert_master
  58  */
  59 enum dlm_status dlmconvert_master(struct dlm_ctxt *dlm,
  60                                   struct dlm_lock_resource *res,
  61                                   struct dlm_lock *lock, int flags, int type)
  62 {
  63         int call_ast = 0, kick_thread = 0;
  64         enum dlm_status status;
  65
  66         spin_lock(&res->spinlock);
  67         /* we are not in a network handler, this is fine */
  68         __dlm_wait_on_lockres(res);
  69         __dlm_lockres_reserve_ast(res);
  70         res->state |= DLM_LOCK_RES_IN_PROGRESS;
  71
  72         status = __dlmconvert_master(dlm, res, lock, flags, type,
  73                                      &call_ast, &kick_thread);
  74
  75         res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
  76         spin_unlock(&res->spinlock);
  77         wake_up(&res->wq);
  78         if (status != DLM_NORMAL && status != DLM_NOTQUEUED)
  79                 dlm_error(status);
  80
  81         /* either queue the ast or release it */
  82         if (call_ast)
  83                 dlm_queue_ast(dlm, lock);
  84         else
  85                 dlm_lockres_release_ast(dlm, res);
  86
  87         if (kick_thread)
  88                 dlm_kick_thread(dlm, res);
  89
  90         return status;
  91 }
  92
  93 /* performs lock conversion at the lockres master site
  94  * locking:
  95  *   caller needs:  res->spinlock
  96  *   taken:         takes and drops lock->spinlock
  97  *   held on exit:  res->spinlock
  98  * returns: DLM_NORMAL, DLM_NOTQUEUED, DLM_DENIED
  99  *   call_ast: whether ast should be called for this lock
 100  *   kick_thread: whether dlm_kick_thread should be called
 101  */
 102 static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
 103                                            struct dlm_lock_resource *res,
 104                                            struct dlm_lock *lock, int flags,
 105                                            int type, int *call_ast,
 106                                            int *kick_thread)
 107 {
 108         enum dlm_status status = DLM_NORMAL;
 109         struct dlm_lock *tmplock=NULL;
 110
 111         assert_spin_locked(&res->spinlock);
 112
 113         mlog(0, "type=%d, convert_type=%d, new convert_type=%d\n",
 114              lock->ml.type, lock->ml.convert_type, type);
 115
 116         spin_lock(&lock->spinlock);
 117
 118         /* already converting? */
 119         if (lock->ml.convert_type != LKM_IVMODE) {
 120                 mlog(ML_ERROR, "attempted to convert a lock with a lock "
 121                      "conversion pending\n");
 122                 status = DLM_DENIED;
 123                 goto unlock_exit;
 124         }
 125
 126         /* must be on grant queue to convert */
 127         if (!dlm_lock_on_list(&res->granted, lock)) {
 128                 mlog(ML_ERROR, "attempted to convert a lock not on grant "
 129                      "queue\n");
 130                 status = DLM_DENIED;
 131                 goto unlock_exit;
 132         }
 133
 134         if (flags & LKM_VALBLK) {
 135                 switch (lock->ml.type) {
 136                         case LKM_EXMODE:
 137                                 /* EX + LKM_VALBLK + convert == set lvb */
 138                                 mlog(0, "will set lvb: converting %s->%s\n",
 139                                      dlm_lock_mode_name(lock->ml.type),
 140                                      dlm_lock_mode_name(type));
 141                                 lock->lksb->flags |= DLM_LKSB_PUT_LVB;
 142                                 break;
 143                         case LKM_PRMODE:
 144                         case LKM_NLMODE:
 145                                 /* refetch if new level is not NL */
 146                                 if (type > LKM_NLMODE) {
 147                                         mlog(0, "will fetch new value into "
 148                                              "lvb: converting %s->%s\n",
 149                                              dlm_lock_mode_name(lock->ml.type),
 150                                              dlm_lock_mode_name(type));
 151                                         lock->lksb->flags |= DLM_LKSB_GET_LVB;
 152                                 } else {
 153                                         mlog(0, "will NOT fetch new value "
 154                                              "into lvb: converting %s->%s\n",
 155                                              dlm_lock_mode_name(lock->ml.type),
 156                                              dlm_lock_mode_name(type));
 157                                         flags &= ~(LKM_VALBLK);
 158                                 }
 159                                 break;
 160                 }
 161         }
 162
 163
 164         /* in-place downconvert? */
 165         if (type <= lock->ml.type)
 166                 goto grant;
 167
 168         /* upconvert from here on */
 169         status = DLM_NORMAL;
 170         list_for_each_entry(tmplock, &res->granted, list) {
 171                 if (tmplock == lock)
 172                         continue;
 173                 if (!dlm_lock_compatible(tmplock->ml.type, type))
 174                         goto switch_queues;
 175         }
 176
 177         list_for_each_entry(tmplock, &res->converting, list) {
 178                 if (!dlm_lock_compatible(tmplock->ml.type, type))
 179                         goto switch_queues;
 180                 /* existing conversion requests take precedence */
 181                 if (!dlm_lock_compatible(tmplock->ml.convert_type, type))
 182                         goto switch_queues;
 183         }
 184
 185         /* fall thru to grant */
 186
 187 grant:
 188         mlog(0, "res %.*s, granting %s lock\n", res->lockname.len,
 189              res->lockname.name, dlm_lock_mode_name(type));
 190         /* immediately grant the new lock type */
 191         lock->lksb->status = DLM_NORMAL;
 192         if (lock->ml.node == dlm->node_num)
 193                 mlog(0, "doing in-place convert for nonlocal lock\n");
 194         lock->ml.type = type;
 195         if (lock->lksb->flags & DLM_LKSB_PUT_LVB)
 196                 memcpy(res->lvb, lock->lksb->lvb, DLM_LVB_LEN);
 197
 198         /*
 199          * Move the lock to the tail because it may be the only lock which has
 200          * an invalid lvb.
 201          */
 202         list_move_tail(&lock->list, &res->granted);
 203
 204         status = DLM_NORMAL;
 205         *call_ast = 1;
 206         goto unlock_exit;
 207
 208 switch_queues:
 209         if (flags & LKM_NOQUEUE) {
 210                 mlog(0, "failed to convert NOQUEUE lock %.*s from "
 211                      "%d to %d...\n", res->lockname.len, res->lockname.name,
 212                      lock->ml.type, type);
 213                 status = DLM_NOTQUEUED;
 214                 goto unlock_exit;
 215         }
 216         mlog(0, "res %.*s, queueing...\n", res->lockname.len,
 217              res->lockname.name);
 218
 219         lock->ml.convert_type = type;
 220         /* do not alter lock refcount.  switching lists. */
 221         list_move_tail(&lock->list, &res->converting);
 222
 223 unlock_exit:
 224         spin_unlock(&lock->spinlock);
 225         if (status == DLM_DENIED) {
 226                 __dlm_print_one_lock_resource(res);
 227         }
 228         if (status == DLM_NORMAL)
 229                 *kick_thread = 1;
 230         return status;
 231 }
 232
 233 void dlm_revert_pending_convert(struct dlm_lock_resource *res,
 234                                 struct dlm_lock *lock)
 235 {
 236         /* do not alter lock refcount.  switching lists. */
 237         list_move_tail(&lock->list, &res->granted);
 238         lock->ml.convert_type = LKM_IVMODE;
 239         lock->lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
 240 }
 241
 242 /* messages the master site to do lock conversion
 243  * locking:
 244  *   caller needs:  none
 245  *   taken:         takes and drops res->spinlock, uses DLM_LOCK_RES_IN_PROGRESS
 246  *   held on exit:  none
 247  * returns: DLM_NORMAL, DLM_RECOVERING, status from remote node
 248  */
 249 enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
 250                                   struct dlm_lock_resource *res,
 251                                   struct dlm_lock *lock, int flags, int type)
 252 {
 253         enum dlm_status status;
 254
 255         mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
 256              lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);
 257
 258         spin_lock(&res->spinlock);
 259         if (res->state & DLM_LOCK_RES_RECOVERING) {
 260                 mlog(0, "bailing out early since res is RECOVERING "
 261                      "on secondary queue\n");
 262                 /* __dlm_print_one_lock_resource(res); */
 263                 status = DLM_RECOVERING;
 264                 goto bail;
 265         }
 266         /* will exit this call with spinlock held */
 267         __dlm_wait_on_lockres(res);
 268
 269         if (lock->ml.convert_type != LKM_IVMODE) {
 270                 __dlm_print_one_lock_resource(res);
 271                 mlog(ML_ERROR, "converting a remote lock that is already "
 272                      "converting! (cookie=%u:%llu, conv=%d)\n",
 273                      dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
 274                      dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
 275                      lock->ml.convert_type);
 276                 status = DLM_DENIED;
 277                 goto bail;
 278         }
 279
 280         if (lock->ml.type == type && lock->ml.convert_type == LKM_IVMODE) {
 281                 mlog(0, "last convert request returned DLM_RECOVERING, but "
 282                      "owner has already queued and sent ast to me. res %.*s, "
 283                      "(cookie=%u:%llu, type=%d, conv=%d)\n",
 284                      res->lockname.len, res->lockname.name,
 285                      dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
 286                      dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
 287                      lock->ml.type, lock->ml.convert_type);
 288                 status = DLM_NORMAL;
 289                 goto bail;
 290         }
 291
 292         res->state |= DLM_LOCK_RES_IN_PROGRESS;
 293         /* move lock to local convert queue */
 294         /* do not alter lock refcount.  switching lists. */
 295         list_move_tail(&lock->list, &res->converting);
 296         lock->convert_pending = 1;
 297         lock->ml.convert_type = type;
 298
 299         if (flags & LKM_VALBLK) {
 300                 if (lock->ml.type == LKM_EXMODE) {
 301                         flags |= LKM_PUT_LVB;
 302                         lock->lksb->flags |= DLM_LKSB_PUT_LVB;
 303                 } else {
 304                         if (lock->ml.convert_type == LKM_NLMODE)
 305                                 flags &= ~LKM_VALBLK;
 306                         else {
 307                                 flags |= LKM_GET_LVB;
 308                                 lock->lksb->flags |= DLM_LKSB_GET_LVB;
 309                         }
 310                 }
 311         }
 312         spin_unlock(&res->spinlock);
 313
 314         /* no locks held here.
 315          * need to wait for a reply as to whether it got queued or not. */
 316         status = dlm_send_remote_convert_request(dlm, res, lock, flags, type);
 317
 318         spin_lock(&res->spinlock);
 319         res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
 320         /* if it failed, move it back to granted queue.
 321          * if master returns DLM_NORMAL and then down before sending ast,
 322          * it may have already been moved to granted queue, reset to
 323          * DLM_RECOVERING and retry convert */
 324         if (status != DLM_NORMAL) {
 325                 if (status != DLM_NOTQUEUED)
 326                         dlm_error(status);
 327                 dlm_revert_pending_convert(res, lock);
 328         } else if (!lock->convert_pending) {
 329                 mlog(0, "%s: res %.*s, owner died and lock has been moved back "
 330                                 "to granted list, retry convert.\n",
 331                                 dlm->name, res->lockname.len, res->lockname.name);
 332                 status = DLM_RECOVERING;
 333         }
 334
 335         lock->convert_pending = 0;
 336 bail:
 337         spin_unlock(&res->spinlock);
 338
 339         /* TODO: should this be a wake_one? */
 340         /* wake up any IN_PROGRESS waiters */
 341         wake_up(&res->wq);
 342
 343         return status;
 344 }
 345
 346 /* sends DLM_CONVERT_LOCK_MSG to master site
 347  * locking:
 348  *   caller needs:  none
 349  *   taken:         none
 350  *   held on exit:  none
 351  * returns: DLM_NOLOCKMGR, status from remote node
 352  */
 353 static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
 354                                            struct dlm_lock_resource *res,
 355                                            struct dlm_lock *lock, int flags, int type)
 356 {
 357         struct dlm_convert_lock convert;
 358         int tmpret;
 359         enum dlm_status ret;
 360         int status = 0;
 361         struct kvec vec[2];
 362         size_t veclen = 1;
 363
 364         mlog(0, "%.*s\n", res->lockname.len, res->lockname.name);
 365
 366         memset(&convert, 0, sizeof(struct dlm_convert_lock));
 367         convert.node_idx = dlm->node_num;
 368         convert.requested_type = type;
 369         convert.cookie = lock->ml.cookie;
 370         convert.namelen = res->lockname.len;
 371         convert.flags = cpu_to_be32(flags);
 372         memcpy(convert.name, res->lockname.name, convert.namelen);
 373
 374         vec[0].iov_len = sizeof(struct dlm_convert_lock);
 375         vec[0].iov_base = &convert;
 376
 377         if (flags & LKM_PUT_LVB) {
 378                 /* extra data to send if we are updating lvb */
 379                 vec[1].iov_len = DLM_LVB_LEN;
 380                 vec[1].iov_base = lock->lksb->lvb;
 381                 veclen++;
 382         }
 383
 384         tmpret = o2net_send_message_vec(DLM_CONVERT_LOCK_MSG, dlm->key,
 385                                         vec, veclen, res->owner, &status);
 386         if (tmpret >= 0) {
 387                 // successfully sent and received
 388                 ret = status;  // this is already a dlm_status
 389                 if (ret == DLM_RECOVERING) {
 390                         mlog(0, "node %u returned DLM_RECOVERING from convert "
 391                              "message!\n", res->owner);
 392                 } else if (ret == DLM_MIGRATING) {
 393                         mlog(0, "node %u returned DLM_MIGRATING from convert "
 394                              "message!\n", res->owner);
 395                 } else if (ret == DLM_FORWARD) {
 396                         mlog(0, "node %u returned DLM_FORWARD from convert "
 397                              "message!\n", res->owner);
 398                 } else if (ret != DLM_NORMAL && ret != DLM_NOTQUEUED)
 399                         dlm_error(ret);
 400         } else {
 401                 mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
 402                      "node %u\n", tmpret, DLM_CONVERT_LOCK_MSG, dlm->key,
 403                      res->owner);
 404                 if (dlm_is_host_down(tmpret)) {
 405                         /* instead of logging the same network error over
 406                          * and over, sleep here and wait for the heartbeat
 407                          * to notice the node is dead.  times out after 5s. */
 408                         dlm_wait_for_node_death(dlm, res->owner,
 409                                                 DLM_NODE_DEATH_WAIT_MAX);
 410                         ret = DLM_RECOVERING;
 411                         mlog(0, "node %u died so returning DLM_RECOVERING "
 412                              "from convert message!\n", res->owner);
 413                 } else {
 414                         ret = dlm_err_to_dlm_status(tmpret);
 415                 }
 416         }
 417
 418         return ret;
 419 }
 420
 421 /* handler for DLM_CONVERT_LOCK_MSG on master site
 422  * locking:
 423  *   caller needs:  none
 424  *   taken:         takes and drop res->spinlock
 425  *   held on exit:  none
 426  * returns: DLM_NORMAL, DLM_IVLOCKID, DLM_BADARGS,
 427  *          status from __dlmconvert_master
 428  */
 429 int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
 430                              void **ret_data)
 431 {
 432         struct dlm_ctxt *dlm = data;
 433         struct dlm_convert_lock *cnv = (struct dlm_convert_lock *)msg->buf;
 434         struct dlm_lock_resource *res = NULL;
 435         struct dlm_lock *lock = NULL;
 436         struct dlm_lock *tmp_lock;
 437         struct dlm_lockstatus *lksb;
 438         enum dlm_status status = DLM_NORMAL;
 439         u32 flags;
 440         int call_ast = 0, kick_thread = 0, ast_reserved = 0, wake = 0;
 441
 442         if (!dlm_grab(dlm)) {
 443                 dlm_error(DLM_REJECTED);
 444                 return DLM_REJECTED;
 445         }
 446
 447         mlog_bug_on_msg(!dlm_domain_fully_joined(dlm),
 448                         "Domain %s not fully joined!\n", dlm->name);
 449
 450         if (cnv->namelen > DLM_LOCKID_NAME_MAX) {
 451                 status = DLM_IVBUFLEN;
 452                 dlm_error(status);
 453                 goto leave;
 454         }
 455
 456         flags = be32_to_cpu(cnv->flags);
 457
 458         if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) ==
 459              (LKM_PUT_LVB|LKM_GET_LVB)) {
 460                 mlog(ML_ERROR, "both PUT and GET lvb specified\n");
 461                 status = DLM_BADARGS;
 462                 goto leave;
 463         }
 464
 465         mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" :
 466              (flags & LKM_GET_LVB ? "get lvb" : "none"));
 467
 468         status = DLM_IVLOCKID;
 469         res = dlm_lookup_lockres(dlm, cnv->name, cnv->namelen);
 470         if (!res) {
 471                 dlm_error(status);
 472                 goto leave;
 473         }
 474
 475         spin_lock(&res->spinlock);
 476         status = __dlm_lockres_state_to_status(res);
 477         if (status != DLM_NORMAL) {
 478                 spin_unlock(&res->spinlock);
 479                 dlm_error(status);
 480                 goto leave;
 481         }
 482         list_for_each_entry(tmp_lock, &res->granted, list) {
 483                 if (tmp_lock->ml.cookie == cnv->cookie &&
 484                     tmp_lock->ml.node == cnv->node_idx) {
 485                         lock = tmp_lock;
 486                         dlm_lock_get(lock);
 487                         break;
 488                 }
 489         }
 490         spin_unlock(&res->spinlock);
 491         if (!lock) {
 492                 status = DLM_IVLOCKID;
 493                 mlog(ML_ERROR, "did not find lock to convert on grant queue! "
 494                                "cookie=%u:%llu\n",
 495                      dlm_get_lock_cookie_node(be64_to_cpu(cnv->cookie)),
 496                      dlm_get_lock_cookie_seq(be64_to_cpu(cnv->cookie)));
 497                 dlm_print_one_lock_resource(res);
 498                 goto leave;
 499         }
 500
 501         /* found the lock */
 502         lksb = lock->lksb;
 503
 504         /* see if caller needed to get/put lvb */
 505         if (flags & LKM_PUT_LVB) {
 506                 BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
 507                 lksb->flags |= DLM_LKSB_PUT_LVB;
 508                 memcpy(&lksb->lvb[0], &cnv->lvb[0], DLM_LVB_LEN);
 509         } else if (flags & LKM_GET_LVB) {
 510                 BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
 511                 lksb->flags |= DLM_LKSB_GET_LVB;
 512         }
 513
 514         spin_lock(&res->spinlock);
 515         status = __dlm_lockres_state_to_status(res);
 516         if (status == DLM_NORMAL) {
 517                 __dlm_lockres_reserve_ast(res);
 518                 ast_reserved = 1;
 519                 res->state |= DLM_LOCK_RES_IN_PROGRESS;
 520                 status = __dlmconvert_master(dlm, res, lock, flags,
 521                                              cnv->requested_type,
 522                                              &call_ast, &kick_thread);
 523                 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
 524                 wake = 1;
 525         }
 526         spin_unlock(&res->spinlock);
 527         if (wake)
 528                 wake_up(&res->wq);
 529
 530         if (status != DLM_NORMAL) {
 531                 if (status != DLM_NOTQUEUED)
 532                         dlm_error(status);
 533                 lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
 534         }
 535
 536 leave:
 537         if (lock)
 538                 dlm_lock_put(lock);
 539
 540         /* either queue the ast or release it, if reserved */
 541         if (call_ast)
 542                 dlm_queue_ast(dlm, lock);
 543         else if (ast_reserved)
 544                 dlm_lockres_release_ast(dlm, res);
 545
 546         if (kick_thread)
 547                 dlm_kick_thread(dlm, res);
 548
 549         if (res)
 550                 dlm_lockres_put(res);
 551
 552         dlm_put(dlm);
 553
 554         return status;
 555 }