source3/modules/onefs_cbrl.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  * Support for OneFS system interfaces.
   4  *
   5  * Copyright (C) Zack Kirsch, 2009
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "includes.h"
  22 #include "onefs.h"
  23
  24 #include <ifs/ifs_syscalls.h>
  25 #include <sys/isi_cifs_brl.h>
  26 #include <isi_ecs/isi_ecs_cbrl.h>
  27
  28 #undef DBGC_CLASS
  29 #define DBGC_CLASS DBGC_LOCKING
  30
  31 extern struct blocking_lock_record *blocking_lock_queue;
  32
  33 static uint64_t onefs_get_new_id(void) {
  34         static uint64_t id = 0;
  35
  36         id++;
  37
  38         return id;
  39 }
  40
  41 enum onefs_cbrl_lock_state {ONEFS_CBRL_NONE, ONEFS_CBRL_ASYNC, ONEFS_CBRL_DONE,
  42         ONEFS_CBRL_ERROR};
  43
  44 struct onefs_cbrl_blr_state {
  45         uint64_t id;
  46         enum onefs_cbrl_lock_state state;
  47 };
  48
  49 static char *onefs_cbrl_blr_state_str(const struct blocking_lock_record *blr)
  50 {
  51         static fstring result;
  52         struct onefs_cbrl_blr_state *bs;
  53
  54         SMB_ASSERT(blr);
  55
  56         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
  57
  58         if (bs == NULL) {
  59                 fstrcpy(result, "NULL CBRL BLR state - Posix lock?");
  60                 return result;
  61         }
  62
  63         switch (bs->state) {
  64         case ONEFS_CBRL_NONE:
  65                 fstr_sprintf(result, "CBRL BLR id=%llu: state=NONE", bs->id);
  66                 break;
  67         case ONEFS_CBRL_ASYNC:
  68                 fstr_sprintf(result, "CBRL BLR id=%llu: state=ASYNC", bs->id);
  69                 break;
  70         case ONEFS_CBRL_DONE:
  71                 fstr_sprintf(result, "CBRL BLR id=%llu: state=DONE", bs->id);
  72                 break;
  73         case ONEFS_CBRL_ERROR:
  74                 fstr_sprintf(result, "CBRL BLR id=%llu: state=ERROR", bs->id);
  75                 break;
  76         default:
  77                 fstr_sprintf(result, "CBRL BLR id=%llu: unknown state %d",
  78                     bs->id, bs->state);
  79                 break;
  80         }
  81
  82         return result;
  83 }
  84
  85 static void onefs_cbrl_enumerate_blq(const char *fn)
  86 {
  87         struct blocking_lock_record *blr;
  88
  89         if (DEBUGLVL(10))
  90                 return;
  91
  92         DEBUG(10, ("CBRL BLR records (%s):\n", fn));
  93
  94         for (blr = blocking_lock_queue; blr; blr = blr->next)
  95                 DEBUGADD(10, ("%s\n", onefs_cbrl_blr_state_str(blr)));
  96 }
  97
  98 static struct blocking_lock_record *onefs_cbrl_find_blr(uint64_t id)
  99 {
 100         struct blocking_lock_record *blr;
 101         struct onefs_cbrl_blr_state *bs;
 102
 103         onefs_cbrl_enumerate_blq("onefs_cbrl_find_blr");
 104
 105         for (blr = blocking_lock_queue; blr; blr = blr->next) {
 106                 bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 107
 108                 /* We don't control all of the BLRs on the BLQ. */
 109                 if (bs == NULL)
 110                         continue;
 111
 112                 if (bs->id == id) {
 113                         DEBUG(10, ("found %s\n",
 114                             onefs_cbrl_blr_state_str(blr)));
 115                         break;
 116                 }
 117         }
 118
 119         if (blr == NULL) {
 120                 DEBUG(5, ("Could not find CBRL BLR for id %llu\n", id));
 121                 return NULL;
 122         }
 123
 124         return blr;
 125 }
 126
 127 static void onefs_cbrl_async_success(uint64_t id)
 128 {
 129         struct blocking_lock_record *blr;
 130         struct onefs_cbrl_blr_state *bs;
 131         uint16 num_locks;
 132
 133         DEBUG(10, ("CBRL async success!\n"));
 134
 135         /* Find BLR with id. Its okay not to find one (race with cancel) */
 136         blr = onefs_cbrl_find_blr(id);
 137         if (blr == NULL)
 138                 return;
 139
 140         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 141         SMB_ASSERT(bs);
 142         SMB_ASSERT(bs->state == ONEFS_CBRL_ASYNC);
 143
 144         blr->lock_num++;
 145
 146         num_locks = SVAL(blr->req->vwv+7, 0);
 147
 148         if (blr->lock_num == num_locks)
 149                 bs->state = ONEFS_CBRL_DONE;
 150         else
 151                 bs->state = ONEFS_CBRL_NONE;
 152
 153         /* Process the queue, to try the next lock or finish up. */
 154         process_blocking_lock_queue();
 155 }
 156
 157 static void onefs_cbrl_async_failure(uint64_t id)
 158 {
 159         struct blocking_lock_record *blr;
 160         struct onefs_cbrl_blr_state *bs;
 161
 162         DEBUG(10, ("CBRL async failure!\n"));
 163
 164         /* Find BLR with id. Its okay not to find one (race with cancel) */
 165         blr = onefs_cbrl_find_blr(id);
 166         if (blr == NULL)
 167                 return;
 168
 169         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 170         SMB_ASSERT(bs);
 171
 172         SMB_ASSERT(bs->state == ONEFS_CBRL_ASYNC);
 173         bs->state = ONEFS_CBRL_ERROR;
 174
 175         /* Process the queue. It will end up trying to retake the same lock,
 176          * see the error in onefs_cbrl_lock_windows() and fail. */
 177         process_blocking_lock_queue();
 178 }
 179
 180 static struct cbrl_event_ops cbrl_ops =
 181     {.cbrl_async_success = onefs_cbrl_async_success,
 182      .cbrl_async_failure = onefs_cbrl_async_failure};
 183
 184 static void onefs_cbrl_events_handler(struct event_context *ev,
 185                                         struct fd_event *fde,
 186                                         uint16_t flags,
 187                                         void *private_data)
 188 {
 189         DEBUG(10, ("onefs_cbrl_events_handler\n"));
 190
 191         if (cbrl_event_dispatcher(&cbrl_ops)) {
 192                 DEBUG(0, ("cbrl_event_dispatcher failed: %s\n",
 193                         strerror(errno)));
 194         }
 195 }
 196
 197 static void onefs_init_cbrl(void)
 198 {
 199         static bool init_done = false;
 200         static int cbrl_event_fd;
 201         static struct fd_event *cbrl_fde;
 202
 203         if (init_done)
 204                 return;
 205
 206         DEBUG(10, ("onefs_init_cbrl\n"));
 207
 208         /* Register the event channel for CBRL. */
 209         cbrl_event_fd = cbrl_event_register();
 210         if (cbrl_event_fd == -1) {
 211                 DEBUG(0, ("cbrl_event_register failed: %s\n",
 212                         strerror(errno)));
 213                 return;
 214         }
 215
 216         DEBUG(10, ("cbrl_event_fd = %d\n", cbrl_event_fd));
 217
 218         /* Register the oplock event_fd with samba's event system */
 219         cbrl_fde = event_add_fd(smbd_event_context(),
 220                                      NULL,
 221                                      cbrl_event_fd,
 222                                      EVENT_FD_READ,
 223                                      onefs_cbrl_events_handler,
 224                                      NULL);
 225
 226         init_done = true;
 227         return;
 228 }
 229
 230 /**
 231  * Blocking PID. As far as I can tell, the blocking_pid is only used to tell
 232  * whether a posix lock or a CIFS lock blocked us. If it was a posix lock,
 233  * Samba polls every 10 seconds, which we don't want. -zkirsch
 234  */
 235 #define ONEFS_BLOCKING_PID 0xABCDABCD
 236
 237 /**
 238  * @param[in]     br_lck        Contains the fsp.
 239  * @param[in]     plock         Lock request.
 240  * @param[in]     blocking_lock Only used for figuring out the error.
 241  * @param[in,out] blr           The BLR for the already-deferred operation.
 242  */
 243 NTSTATUS onefs_brl_lock_windows(vfs_handle_struct *handle,
 244                                 struct byte_range_lock *br_lck,
 245                                 struct lock_struct *plock,
 246                                 bool blocking_lock,
 247                                 struct blocking_lock_record *blr)
 248 {
 249         int fd = br_lck->fsp->fh->fd;
 250         uint64_t id = 0;
 251         enum cbrl_lock_type type;
 252         bool async = false;
 253         bool pending = false;
 254         bool pending_async = false;
 255         int error;
 256         struct onefs_cbrl_blr_state *bs;
 257         NTSTATUS status;
 258
 259         START_PROFILE(syscall_brl_lock);
 260
 261         SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
 262         SMB_ASSERT(plock->lock_type != UNLOCK_LOCK);
 263
 264         onefs_cbrl_enumerate_blq("onefs_brl_lock_windows");
 265
 266         /* Will only initialize the first time its called. */
 267         onefs_init_cbrl();
 268
 269         switch (plock->lock_type) {
 270                 case WRITE_LOCK:
 271                         type = CBRL_LK_EX;
 272                         break;
 273                 case READ_LOCK:
 274                         type = CBRL_LK_SH;
 275                         break;
 276                 case PENDING_WRITE_LOCK:
 277                         /* Called when a blocking lock request is added - do an
 278                          * async lock. */
 279                         type = CBRL_LK_EX;
 280                         pending = true;
 281                         async = true;
 282                         break;
 283                 case PENDING_READ_LOCK:
 284                         /* Called when a blocking lock request is added - do an
 285                          * async lock. */
 286                         type = CBRL_LK_SH;
 287                         pending = true;
 288                         async = true;
 289                         break;
 290                 default:
 291                         /* UNLOCK_LOCK: should only be used for a POSIX_LOCK */
 292                         smb_panic("Invalid plock->lock_type passed in to "
 293                             "onefs_brl_lock_windows");
 294         }
 295
 296         /* Figure out if we're actually doing the lock or a no-op. We need to
 297          * do a no-op when process_blocking_lock_queue calls back into us.
 298          *
 299          * We know process_* is calling into us if a blr is passed in and
 300          * pending is false. */
 301         if (!pending && blr) {
 302                 /* Check the BLR state. */
 303                 bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 304                 SMB_ASSERT(bs);
 305
 306                 /* ASYNC still in progress: The process_* calls will keep
 307                  * calling even if we haven't gotten the lock. Keep erroring
 308                  * without calling ifs_cbrl, or getting/setting an id. */
 309                 if (bs->state == ONEFS_CBRL_ASYNC) {
 310                         goto failure;
 311                 }
 312                 else if (bs->state == ONEFS_CBRL_ERROR) {
 313                         END_PROFILE(syscall_brl_lock);
 314                         return NT_STATUS_NO_MEMORY;
 315                 }
 316
 317                 SMB_ASSERT(bs->state == ONEFS_CBRL_NONE);
 318                 async = true;
 319         }
 320
 321         if (async) {
 322                 SMB_ASSERT(blocking_lock);
 323                 SMB_ASSERT(blr);
 324                 id = onefs_get_new_id();
 325         }
 326
 327         DEBUG(10, ("Calling ifs_cbrl(LOCK)..."));
 328         error = ifs_cbrl(fd, CBRL_OP_LOCK, type, plock->start,
 329             plock->size, async, id, plock->context.smbpid, plock->context.tid,
 330             plock->fnum);
 331         if (!error) {
 332                 goto success;
 333         } else if (errno == EWOULDBLOCK) {
 334                 SMB_ASSERT(!async);
 335         } else if (errno == EINPROGRESS) {
 336                 SMB_ASSERT(async);
 337
 338                 if (pending) {
 339                         /* Talloc a new BLR private state. */
 340                         blr->blr_private = talloc(blr, struct onefs_cbrl_blr_state);
 341                         pending_async = true;
 342                 }
 343
 344                 /* Store the new id in the BLR private state. */
 345                 bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 346                 bs->id = id;
 347                 bs->state = ONEFS_CBRL_ASYNC;
 348         } else {
 349                 DEBUG(0, ("onefs_brl_lock_windows failure: error=%d (%s).\n",
 350                         errno, strerror(errno)));
 351         }
 352
 353 failure:
 354
 355         END_PROFILE(syscall_brl_lock);
 356
 357         /* Failure - error or async. */
 358         plock->context.smbpid = (uint32) ONEFS_BLOCKING_PID;
 359
 360         if (pending_async)
 361                 status = NT_STATUS_OK;
 362         else
 363                 status = brl_lock_failed(br_lck->fsp, plock, blocking_lock);
 364
 365         DEBUG(10, ("returning %s.\n", nt_errstr(status)));
 366         return status;
 367
 368 success:
 369
 370         END_PROFILE(syscall_brl_lock);
 371
 372         /* Success. */
 373         onefs_cbrl_enumerate_blq("onefs_brl_unlock_windows");
 374         DEBUG(10, ("returning NT_STATUS_OK.\n"));
 375         return NT_STATUS_OK;
 376 }
 377
 378 bool onefs_brl_unlock_windows(vfs_handle_struct *handle,
 379                               struct messaging_context *msg_ctx,
 380                               struct byte_range_lock *br_lck,
 381                               const struct lock_struct *plock)
 382 {
 383         int error;
 384         int fd = br_lck->fsp->fh->fd;
 385
 386         START_PROFILE(syscall_brl_unlock);
 387
 388         SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
 389         SMB_ASSERT(plock->lock_type == UNLOCK_LOCK);
 390
 391         DEBUG(10, ("Calling ifs_cbrl(UNLOCK)..."));
 392         error = ifs_cbrl(fd, CBRL_OP_UNLOCK, CBRL_LK_SH,
 393             plock->start, plock->size, false, 0, plock->context.smbpid,
 394             plock->context.tid, plock->fnum);
 395
 396         END_PROFILE(syscall_brl_unlock);
 397
 398         if (error) {
 399                 DEBUG(10, ("returning false.\n"));
 400                 return false;
 401         }
 402
 403         DEBUG(10, ("returning true.\n"));
 404         return true;
 405
 406         /* Problem with storing things in TDB: I won't know what BRL to unlock in the TDB.
 407          *  - I could fake it?
 408          *  - I could send Samba a message with which lock is being unlocked?
 409          *  - I could *easily* make the "id" something you always pass in to
 410          *  lock, unlock or cancel -- it identifies a lock. Makes sense!
 411          */
 412 }
 413
 414 /* Default implementation only calls this on PENDING locks. */
 415 bool onefs_brl_cancel_windows(vfs_handle_struct *handle,
 416                               struct byte_range_lock *br_lck,
 417                               struct lock_struct *plock,
 418                               struct blocking_lock_record *blr)
 419 {
 420         int error;
 421         int fd = br_lck->fsp->fh->fd;
 422         struct onefs_cbrl_blr_state *bs;
 423
 424         START_PROFILE(syscall_brl_cancel);
 425
 426         SMB_ASSERT(plock);
 427         SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
 428         SMB_ASSERT(blr);
 429
 430         onefs_cbrl_enumerate_blq("onefs_brl_cancel_windows");
 431
 432         bs = ((struct onefs_cbrl_blr_state *)blr->blr_private);
 433         SMB_ASSERT(bs);
 434
 435         if (bs->state == ONEFS_CBRL_DONE || bs->state == ONEFS_CBRL_ERROR) {
 436                 /* No-op. */
 437                 DEBUG(10, ("State=%d, returning true\n", bs->state));
 438                 END_PROFILE(syscall_brl_cancel);
 439                 return true;
 440         }
 441
 442         SMB_ASSERT(bs->state == ONEFS_CBRL_NONE ||
 443             bs->state == ONEFS_CBRL_ASYNC);
 444
 445         /* A real cancel. */
 446         DEBUG(10, ("Calling ifs_cbrl(CANCEL)..."));
 447         error = ifs_cbrl(fd, CBRL_OP_CANCEL, CBRL_LK_UNSPEC, plock->start,
 448             plock->size, false, bs->id, plock->context.smbpid,
 449             plock->context.tid, plock->fnum);
 450
 451         END_PROFILE(syscall_brl_cancel);
 452
 453         if (error) {
 454                 DEBUG(10, ("returning false\n"));
 455                 bs->state = ONEFS_CBRL_ERROR;
 456                 return false;
 457         }
 458
 459         bs->state = ONEFS_CBRL_DONE;
 460         onefs_cbrl_enumerate_blq("onefs_brl_cancel_windows");
 461         DEBUG(10, ("returning true\n"));
 462         return true;
 463 }
 464
 465 bool onefs_strict_lock(vfs_handle_struct *handle,
 466                         files_struct *fsp,
 467                         struct lock_struct *plock)
 468 {
 469         int error;
 470
 471         START_PROFILE(syscall_strict_lock);
 472
 473         SMB_ASSERT(plock->lock_type == READ_LOCK ||
 474             plock->lock_type == WRITE_LOCK);
 475
 476         if (!lp_locking(handle->conn->params) ||
 477             !lp_strict_locking(handle->conn->params)) {
 478                 END_PROFILE(syscall_strict_lock);
 479                 return True;
 480         }
 481
 482         if (plock->lock_flav == POSIX_LOCK) {
 483                 END_PROFILE(syscall_strict_lock);
 484                 return SMB_VFS_NEXT_STRICT_LOCK(handle, fsp, plock);
 485         }
 486
 487         if (plock->size == 0) {
 488                 END_PROFILE(syscall_strict_lock);
 489                 return True;
 490         }
 491
 492         error = ifs_cbrl(fsp->fh->fd, CBRL_OP_LOCK,
 493             plock->lock_type == READ_LOCK ? CBRL_LK_RD : CBRL_LK_WR,
 494             plock->start, plock->size, 0, 0, plock->context.smbpid,
 495             plock->context.tid, plock->fnum);
 496
 497         END_PROFILE(syscall_strict_lock);
 498
 499         return (error == 0);
 500 }
 501
 502 void onefs_strict_unlock(vfs_handle_struct *handle,
 503                         files_struct *fsp,
 504                         struct lock_struct *plock)
 505 {
 506         START_PROFILE(syscall_strict_unlock);
 507
 508         SMB_ASSERT(plock->lock_type == READ_LOCK ||
 509             plock->lock_type == WRITE_LOCK);
 510
 511         if (!lp_locking(handle->conn->params) ||
 512             !lp_strict_locking(handle->conn->params)) {
 513                 END_PROFILE(syscall_strict_unlock);
 514                 return;
 515         }
 516
 517         if (plock->lock_flav == POSIX_LOCK) {
 518                 SMB_VFS_NEXT_STRICT_UNLOCK(handle, fsp, plock);
 519                 END_PROFILE(syscall_strict_unlock);
 520                 return;
 521         }
 522
 523         if (plock->size == 0) {
 524                 END_PROFILE(syscall_strict_unlock);
 525                 return;
 526         }
 527
 528         if (fsp->fh) {
 529                 ifs_cbrl(fsp->fh->fd, CBRL_OP_UNLOCK,
 530                     plock->lock_type == READ_LOCK ? CBRL_LK_RD : CBRL_LK_WR,
 531                     plock->start, plock->size, 0, 0, plock->context.smbpid,
 532                     plock->context.tid, plock->fnum);
 533         }
 534
 535         END_PROFILE(syscall_strict_unlock);
 536 }
 537
 538 /* TODO Optimization: Abstract out brl_get_locks() in the Windows case.
 539  * We'll malloc some memory or whatever (can't return NULL), but not actually
 540  * touch the TDB. */
 541
 542 /* XXX brl_locktest: CBRL does not support calling this, but its only for
 543  * strict locking. Add empty VOP? */
 544
 545 /* XXX brl_lockquery: CBRL does not support calling this for WINDOWS LOCKS, but
 546  * its only called for POSIX LOCKS. Add empty VOP? */
 547
 548 /* XXX brl_close_fnum: CBRL will do this automatically. I think this is a NO-OP
 549  * for us, we could add an empty VOP. */
 550