source3/smbd/aio.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    async_io read handling using POSIX async io.
   5    Copyright (C) Jeremy Allison 2005.
   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
  23 #if defined(WITH_AIO)
  24
  25 /* The signal we'll use to signify aio done. */
  26 #ifndef RT_SIGNAL_AIO
  27 #define RT_SIGNAL_AIO (SIGRTMIN+3)
  28 #endif
  29
  30 /****************************************************************************
  31  The buffer we keep around whilst an aio request is in process.
  32 *****************************************************************************/
  33
  34 struct aio_extra {
  35         struct aio_extra *next, *prev;
  36         SMB_STRUCT_AIOCB acb;
  37         files_struct *fsp;
  38         bool read_req;
  39         uint16 mid;
  40         char *inbuf;
  41         char *outbuf;
  42 };
  43
  44 static struct aio_extra *aio_list_head;
  45
  46 /****************************************************************************
  47  Create the extended aio struct we must keep around for the lifetime
  48  of the aio_read call.
  49 *****************************************************************************/
  50
  51 static struct aio_extra *create_aio_ex_read(files_struct *fsp, size_t buflen,
  52                                             uint16 mid)
  53 {
  54         struct aio_extra *aio_ex = SMB_MALLOC_P(struct aio_extra);
  55
  56         if (!aio_ex) {
  57                 return NULL;
  58         }
  59         ZERO_STRUCTP(aio_ex);
  60         /* The output buffer stored in the aio_ex is the start of
  61            the smb return buffer. The buffer used in the acb
  62            is the start of the reply data portion of that buffer. */
  63         aio_ex->outbuf = SMB_MALLOC_ARRAY(char, buflen);
  64         if (!aio_ex->outbuf) {
  65                 SAFE_FREE(aio_ex);
  66                 return NULL;
  67         }
  68         DLIST_ADD(aio_list_head, aio_ex);
  69         aio_ex->fsp = fsp;
  70         aio_ex->read_req = True;
  71         aio_ex->mid = mid;
  72         return aio_ex;
  73 }
  74
  75 /****************************************************************************
  76  Create the extended aio struct we must keep around for the lifetime
  77  of the aio_write call.
  78 *****************************************************************************/
  79
  80 static struct aio_extra *create_aio_ex_write(files_struct *fsp,
  81                                              size_t inbuflen,
  82                                              size_t outbuflen,
  83                                              uint16 mid)
  84 {
  85         struct aio_extra *aio_ex = SMB_MALLOC_P(struct aio_extra);
  86
  87         if (!aio_ex) {
  88                 return NULL;
  89         }
  90         ZERO_STRUCTP(aio_ex);
  91
  92         /* We need space for an output reply of outbuflen bytes. */
  93         aio_ex->outbuf = SMB_MALLOC_ARRAY(char, outbuflen);
  94         if (!aio_ex->outbuf) {
  95                 SAFE_FREE(aio_ex);
  96                 return NULL;
  97         }
  98
  99         if (!(aio_ex->inbuf = SMB_MALLOC_ARRAY(char, inbuflen))) {
 100                 SAFE_FREE(aio_ex->outbuf);
 101                 SAFE_FREE(aio_ex);
 102                 return NULL;
 103         }
 104
 105         DLIST_ADD(aio_list_head, aio_ex);
 106         aio_ex->fsp = fsp;
 107         aio_ex->read_req = False;
 108         aio_ex->mid = mid;
 109         return aio_ex;
 110 }
 111
 112 /****************************************************************************
 113  Delete the extended aio struct.
 114 *****************************************************************************/
 115
 116 static void delete_aio_ex(struct aio_extra *aio_ex)
 117 {
 118         DLIST_REMOVE(aio_list_head, aio_ex);
 119         SAFE_FREE(aio_ex->inbuf);
 120         SAFE_FREE(aio_ex->outbuf);
 121         SAFE_FREE(aio_ex);
 122 }
 123
 124 /****************************************************************************
 125  Given the aiocb struct find the extended aio struct containing it.
 126 *****************************************************************************/
 127
 128 static struct aio_extra *find_aio_ex(uint16 mid)
 129 {
 130         struct aio_extra *p;
 131
 132         for( p = aio_list_head; p; p = p->next) {
 133                 if (mid == p->mid) {
 134                         return p;
 135                 }
 136         }
 137         return NULL;
 138 }
 139
 140 /****************************************************************************
 141  We can have these many aio buffers in flight.
 142 *****************************************************************************/
 143
 144 #define AIO_PENDING_SIZE 10
 145 static sig_atomic_t signals_received;
 146 static int outstanding_aio_calls;
 147 static uint16 aio_pending_array[AIO_PENDING_SIZE];
 148
 149 /****************************************************************************
 150  Signal handler when an aio request completes.
 151 *****************************************************************************/
 152
 153 static void signal_handler(int sig, siginfo_t *info, void *unused)
 154 {
 155         if (signals_received < AIO_PENDING_SIZE) {
 156                 aio_pending_array[signals_received] = info->si_value.sival_int;
 157                 signals_received++;
 158         } /* Else signal is lost. */
 159         sys_select_signal(RT_SIGNAL_AIO);
 160 }
 161
 162 /****************************************************************************
 163  Is there a signal waiting ?
 164 *****************************************************************************/
 165
 166 bool aio_finished(void)
 167 {
 168         return (signals_received != 0);
 169 }
 170
 171 /****************************************************************************
 172  Initialize the signal handler for aio read/write.
 173 *****************************************************************************/
 174
 175 void initialize_async_io_handler(void)
 176 {
 177         struct sigaction act;
 178
 179         ZERO_STRUCT(act);
 180         act.sa_sigaction = signal_handler;
 181         act.sa_flags = SA_SIGINFO;
 182         sigemptyset( &act.sa_mask );
 183         if (sigaction(RT_SIGNAL_AIO, &act, NULL) != 0) {
 184                 DEBUG(0,("Failed to setup RT_SIGNAL_AIO handler\n"));
 185         }
 186
 187         /* the signal can start off blocked due to a bug in bash */
 188         BlockSignals(False, RT_SIGNAL_AIO);
 189 }
 190
 191 /****************************************************************************
 192  Set up an aio request from a SMBreadX call.
 193 *****************************************************************************/
 194
 195 bool schedule_aio_read_and_X(connection_struct *conn,
 196                              struct smb_request *req,
 197                              files_struct *fsp, SMB_OFF_T startpos,
 198                              size_t smb_maxcnt)
 199 {
 200         struct aio_extra *aio_ex;
 201         SMB_STRUCT_AIOCB *a;
 202         size_t bufsize;
 203         size_t min_aio_read_size = lp_aio_read_size(SNUM(conn));
 204
 205         if (!min_aio_read_size || (smb_maxcnt < min_aio_read_size)) {
 206                 /* Too small a read for aio request. */
 207                 DEBUG(10,("schedule_aio_read_and_X: read size (%u) too small "
 208                           "for minimum aio_read of %u\n",
 209                           (unsigned int)smb_maxcnt,
 210                           (unsigned int)min_aio_read_size ));
 211                 return False;
 212         }
 213
 214         /* Only do this on non-chained and non-chaining reads not using the
 215          * write cache. */
 216         if (chain_size !=0 || (CVAL(req->inbuf,smb_vwv0) != 0xFF)
 217             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 218                 return False;
 219         }
 220
 221         if (outstanding_aio_calls >= AIO_PENDING_SIZE) {
 222                 DEBUG(10,("schedule_aio_read_and_X: Already have %d aio "
 223                           "activities outstanding.\n",
 224                           outstanding_aio_calls ));
 225                 return False;
 226         }
 227
 228         /* The following is safe from integer wrap as we've already checked
 229            smb_maxcnt is 128k or less. Wct is 12 for read replies */
 230
 231         bufsize = smb_size + 12 * 2 + smb_maxcnt;
 232
 233         if ((aio_ex = create_aio_ex_read(fsp, bufsize, req->mid)) == NULL) {
 234                 DEBUG(10,("schedule_aio_read_and_X: malloc fail.\n"));
 235                 return False;
 236         }
 237
 238         construct_reply_common((char *)req->inbuf, aio_ex->outbuf);
 239         srv_set_message(aio_ex->outbuf, 12, 0, True);
 240         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 241
 242         a = &aio_ex->acb;
 243
 244         /* Now set up the aio record for the read call. */
 245
 246         a->aio_fildes = fsp->fh->fd;
 247         a->aio_buf = smb_buf(aio_ex->outbuf);
 248         a->aio_nbytes = smb_maxcnt;
 249         a->aio_offset = startpos;
 250         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 251         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 252         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 253
 254         if (SMB_VFS_AIO_READ(fsp,a) == -1) {
 255                 DEBUG(0,("schedule_aio_read_and_X: aio_read failed. "
 256                          "Error %s\n", strerror(errno) ));
 257                 delete_aio_ex(aio_ex);
 258                 return False;
 259         }
 260
 261         DEBUG(10,("schedule_aio_read_and_X: scheduled aio_read for file %s, "
 262                   "offset %.0f, len = %u (mid = %u)\n",
 263                   fsp->fsp_name, (double)startpos, (unsigned int)smb_maxcnt,
 264                   (unsigned int)aio_ex->mid ));
 265
 266         srv_defer_sign_response(aio_ex->mid);
 267         outstanding_aio_calls++;
 268         return True;
 269 }
 270
 271 /****************************************************************************
 272  Set up an aio request from a SMBwriteX call.
 273 *****************************************************************************/
 274
 275 bool schedule_aio_write_and_X(connection_struct *conn,
 276                               struct smb_request *req,
 277                               files_struct *fsp, char *data,
 278                               SMB_OFF_T startpos,
 279                               size_t numtowrite)
 280 {
 281         struct aio_extra *aio_ex;
 282         SMB_STRUCT_AIOCB *a;
 283         size_t inbufsize, outbufsize;
 284         bool write_through = BITSETW(req->inbuf+smb_vwv7,0);
 285         size_t min_aio_write_size = lp_aio_write_size(SNUM(conn));
 286
 287         if (!min_aio_write_size || (numtowrite < min_aio_write_size)) {
 288                 /* Too small a write for aio request. */
 289                 DEBUG(10,("schedule_aio_write_and_X: write size (%u) too "
 290                           "small for minimum aio_write of %u\n",
 291                           (unsigned int)numtowrite,
 292                           (unsigned int)min_aio_write_size ));
 293                 return False;
 294         }
 295
 296         /* Only do this on non-chained and non-chaining reads not using the
 297          * write cache. */
 298         if (chain_size !=0 || (CVAL(req->inbuf,smb_vwv0) != 0xFF)
 299             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 300                 return False;
 301         }
 302
 303         if (outstanding_aio_calls >= AIO_PENDING_SIZE) {
 304                 DEBUG(3,("schedule_aio_write_and_X: Already have %d aio "
 305                          "activities outstanding.\n",
 306                           outstanding_aio_calls ));
 307                 DEBUG(10,("schedule_aio_write_and_X: failed to schedule "
 308                           "aio_write for file %s, offset %.0f, len = %u "
 309                           "(mid = %u)\n",
 310                           fsp->fsp_name, (double)startpos,
 311                           (unsigned int)numtowrite,
 312                           (unsigned int)req->mid ));
 313                 return False;
 314         }
 315
 316         inbufsize =  smb_len(req->inbuf) + 4;
 317         reply_outbuf(req, 6, 0);
 318         outbufsize = smb_len(req->outbuf) + 4;
 319         if (!(aio_ex = create_aio_ex_write(fsp, inbufsize, outbufsize,
 320                                            req->mid))) {
 321                 DEBUG(0,("schedule_aio_write_and_X: malloc fail.\n"));
 322                 return False;
 323         }
 324
 325         /* Copy the SMB header already setup in outbuf. */
 326         memcpy(aio_ex->inbuf, req->inbuf, inbufsize);
 327
 328         /* Copy the SMB header already setup in outbuf. */
 329         memcpy(aio_ex->outbuf, req->outbuf, outbufsize);
 330         TALLOC_FREE(req->outbuf);
 331         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 332
 333         a = &aio_ex->acb;
 334
 335         /* Now set up the aio record for the write call. */
 336
 337         a->aio_fildes = fsp->fh->fd;
 338         a->aio_buf = aio_ex->inbuf + (PTR_DIFF(data, req->inbuf));
 339         a->aio_nbytes = numtowrite;
 340         a->aio_offset = startpos;
 341         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 342         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 343         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 344
 345         if (SMB_VFS_AIO_WRITE(fsp,a) == -1) {
 346                 DEBUG(3,("schedule_aio_wrote_and_X: aio_write failed. "
 347                          "Error %s\n", strerror(errno) ));
 348                 delete_aio_ex(aio_ex);
 349                 return False;
 350         }
 351
 352         if (!write_through && !lp_syncalways(SNUM(fsp->conn))
 353             && fsp->aio_write_behind) {
 354                 /* Lie to the client and immediately claim we finished the
 355                  * write. */
 356                 SSVAL(aio_ex->outbuf,smb_vwv2,numtowrite);
 357                 SSVAL(aio_ex->outbuf,smb_vwv4,(numtowrite>>16)&1);
 358                 show_msg(aio_ex->outbuf);
 359                 if (!srv_send_smb(smbd_server_fd(),aio_ex->outbuf,
 360                                 IS_CONN_ENCRYPTED(fsp->conn))) {
 361                         exit_server_cleanly("handle_aio_write: srv_send_smb "
 362                                             "failed.");
 363                 }
 364                 DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write "
 365                           "behind for file %s\n", fsp->fsp_name ));
 366         } else {
 367                 srv_defer_sign_response(aio_ex->mid);
 368         }
 369         outstanding_aio_calls++;
 370
 371         DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write for file "
 372                   "%s, offset %.0f, len = %u (mid = %u) "
 373                   "outstanding_aio_calls = %d\n",
 374                   fsp->fsp_name, (double)startpos, (unsigned int)numtowrite,
 375                   (unsigned int)aio_ex->mid, outstanding_aio_calls ));
 376
 377         return True;
 378 }
 379
 380
 381 /****************************************************************************
 382  Complete the read and return the data or error back to the client.
 383  Returns errno or zero if all ok.
 384 *****************************************************************************/
 385
 386 static int handle_aio_read_complete(struct aio_extra *aio_ex)
 387 {
 388         int ret = 0;
 389         int outsize;
 390         char *outbuf = aio_ex->outbuf;
 391         char *data = smb_buf(outbuf);
 392         ssize_t nread = SMB_VFS_AIO_RETURN(aio_ex->fsp,&aio_ex->acb);
 393
 394         if (nread < 0) {
 395                 /* We're relying here on the fact that if the fd is
 396                    closed then the aio will complete and aio_return
 397                    will return an error. Hopefully this is
 398                    true.... JRA. */
 399
 400                 /* If errno is ECANCELED then don't return anything to the
 401                  * client. */
 402                 if (errno == ECANCELED) {
 403                         srv_cancel_sign_response(aio_ex->mid);
 404                         return 0;
 405                 }
 406
 407                 DEBUG( 3,( "handle_aio_read_complete: file %s nread == -1. "
 408                            "Error = %s\n",
 409                            aio_ex->fsp->fsp_name, strerror(errno) ));
 410
 411                 ret = errno;
 412                 ERROR_NT(map_nt_error_from_unix(ret));
 413                 outsize = srv_set_message(outbuf,0,0,true);
 414         } else {
 415                 outsize = srv_set_message(outbuf,12,nread,False);
 416                 SSVAL(outbuf,smb_vwv2,0xFFFF); /* Remaining - must be * -1. */
 417                 SSVAL(outbuf,smb_vwv5,nread);
 418                 SSVAL(outbuf,smb_vwv6,smb_offset(data,outbuf));
 419                 SSVAL(outbuf,smb_vwv7,((nread >> 16) & 1));
 420                 SSVAL(smb_buf(outbuf),-2,nread);
 421
 422                 DEBUG( 3, ( "handle_aio_read_complete file %s max=%d "
 423                             "nread=%d\n",
 424                             aio_ex->fsp->fsp_name,
 425                             (int)aio_ex->acb.aio_nbytes, (int)nread ) );
 426
 427         }
 428         smb_setlen(outbuf,outsize - 4);
 429         show_msg(outbuf);
 430         if (!srv_send_smb(smbd_server_fd(),outbuf,
 431                         IS_CONN_ENCRYPTED(aio_ex->fsp->conn))) {
 432                 exit_server_cleanly("handle_aio_read_complete: srv_send_smb "
 433                                     "failed.");
 434         }
 435
 436         DEBUG(10,("handle_aio_read_complete: scheduled aio_read completed "
 437                   "for file %s, offset %.0f, len = %u\n",
 438                   aio_ex->fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 439                   (unsigned int)nread ));
 440
 441         return ret;
 442 }
 443
 444 /****************************************************************************
 445  Complete the write and return the data or error back to the client.
 446  Returns errno or zero if all ok.
 447 *****************************************************************************/
 448
 449 static int handle_aio_write_complete(struct aio_extra *aio_ex)
 450 {
 451         int ret = 0;
 452         files_struct *fsp = aio_ex->fsp;
 453         char *outbuf = aio_ex->outbuf;
 454         ssize_t numtowrite = aio_ex->acb.aio_nbytes;
 455         ssize_t nwritten = SMB_VFS_AIO_RETURN(fsp,&aio_ex->acb);
 456
 457         if (fsp->aio_write_behind) {
 458                 if (nwritten != numtowrite) {
 459                         if (nwritten == -1) {
 460                                 DEBUG(5,("handle_aio_write_complete: "
 461                                          "aio_write_behind failed ! File %s "
 462                                          "is corrupt ! Error %s\n",
 463                                          fsp->fsp_name, strerror(errno) ));
 464                                 ret = errno;
 465                         } else {
 466                                 DEBUG(0,("handle_aio_write_complete: "
 467                                          "aio_write_behind failed ! File %s "
 468                                          "is corrupt ! Wanted %u bytes but "
 469                                          "only wrote %d\n", fsp->fsp_name,
 470                                          (unsigned int)numtowrite,
 471                                          (int)nwritten ));
 472                                 ret = EIO;
 473                         }
 474                 } else {
 475                         DEBUG(10,("handle_aio_write_complete: "
 476                                   "aio_write_behind completed for file %s\n",
 477                                   fsp->fsp_name ));
 478                 }
 479                 return 0;
 480         }
 481
 482         /* We don't need outsize or set_message here as we've already set the
 483            fixed size length when we set up the aio call. */
 484
 485         if(nwritten == -1) {
 486                 DEBUG( 3,( "handle_aio_write: file %s wanted %u bytes. "
 487                            "nwritten == %d. Error = %s\n",
 488                            fsp->fsp_name, (unsigned int)numtowrite,
 489                            (int)nwritten, strerror(errno) ));
 490
 491                 /* If errno is ECANCELED then don't return anything to the
 492                  * client. */
 493                 if (errno == ECANCELED) {
 494                         srv_cancel_sign_response(aio_ex->mid);
 495                         return 0;
 496                 }
 497
 498                 ret = errno;
 499                 ERROR_BOTH(map_nt_error_from_unix(ret), ERRHRD, ERRdiskfull);
 500                 srv_set_message(outbuf,0,0,true);
 501         } else {
 502                 bool write_through = BITSETW(aio_ex->inbuf+smb_vwv7,0);
 503                 NTSTATUS status;
 504
 505                 SSVAL(outbuf,smb_vwv2,nwritten);
 506                 SSVAL(outbuf,smb_vwv4,(nwritten>>16)&1);
 507                 if (nwritten < (ssize_t)numtowrite) {
 508                         SCVAL(outbuf,smb_rcls,ERRHRD);
 509                         SSVAL(outbuf,smb_err,ERRdiskfull);
 510                 }
 511
 512                 DEBUG(3,("handle_aio_write: fnum=%d num=%d wrote=%d\n",
 513                          fsp->fnum, (int)numtowrite, (int)nwritten));
 514                 status = sync_file(fsp->conn,fsp, write_through);
 515                 if (!NT_STATUS_IS_OK(status)) {
 516                         ret = errno;
 517                         ERROR_BOTH(map_nt_error_from_unix(ret),
 518                                    ERRHRD, ERRdiskfull);
 519                         srv_set_message(outbuf,0,0,true);
 520                         DEBUG(5,("handle_aio_write: sync_file for %s returned %s\n",
 521                                 fsp->fsp_name, nt_errstr(status) ));
 522                 }
 523         }
 524
 525         show_msg(outbuf);
 526         if (!srv_send_smb(smbd_server_fd(),outbuf,IS_CONN_ENCRYPTED(fsp->conn))) {
 527                 exit_server_cleanly("handle_aio_write: srv_send_smb failed.");
 528         }
 529
 530         DEBUG(10,("handle_aio_write_complete: scheduled aio_write completed "
 531                   "for file %s, offset %.0f, requested %u, written = %u\n",
 532                   fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 533                   (unsigned int)numtowrite, (unsigned int)nwritten ));
 534
 535         return ret;
 536 }
 537
 538 /****************************************************************************
 539  Handle any aio completion. Returns True if finished (and sets *perr if err
 540  was non-zero), False if not.
 541 *****************************************************************************/
 542
 543 static bool handle_aio_completed(struct aio_extra *aio_ex, int *perr)
 544 {
 545         int err;
 546
 547         /* Ensure the operation has really completed. */
 548         if (SMB_VFS_AIO_ERROR(aio_ex->fsp, &aio_ex->acb) == EINPROGRESS) {
 549                 DEBUG(10,( "handle_aio_completed: operation mid %u still in "
 550                            "process for file %s\n",
 551                            aio_ex->mid, aio_ex->fsp->fsp_name ));
 552                 return False;
 553         }
 554
 555         if (aio_ex->read_req) {
 556                 err = handle_aio_read_complete(aio_ex);
 557         } else {
 558                 err = handle_aio_write_complete(aio_ex);
 559         }
 560
 561         if (err) {
 562                 *perr = err; /* Only save non-zero errors. */
 563         }
 564
 565         return True;
 566 }
 567
 568 /****************************************************************************
 569  Handle any aio completion inline.
 570  Returns non-zero errno if fail or zero if all ok.
 571 *****************************************************************************/
 572
 573 int process_aio_queue(void)
 574 {
 575         int i;
 576         int ret = 0;
 577
 578         BlockSignals(True, RT_SIGNAL_AIO);
 579
 580         DEBUG(10,("process_aio_queue: signals_received = %d\n",
 581                   (int)signals_received));
 582         DEBUG(10,("process_aio_queue: outstanding_aio_calls = %d\n",
 583                   outstanding_aio_calls));
 584
 585         if (!signals_received) {
 586                 BlockSignals(False, RT_SIGNAL_AIO);
 587                 return 0;
 588         }
 589
 590         /* Drain all the complete aio_reads. */
 591         for (i = 0; i < signals_received; i++) {
 592                 uint16 mid = aio_pending_array[i];
 593                 files_struct *fsp = NULL;
 594                 struct aio_extra *aio_ex = find_aio_ex(mid);
 595
 596                 if (!aio_ex) {
 597                         DEBUG(3,("process_aio_queue: Can't find record to "
 598                                  "match mid %u.\n", (unsigned int)mid));
 599                         srv_cancel_sign_response(mid);
 600                         continue;
 601                 }
 602
 603                 fsp = aio_ex->fsp;
 604                 if (fsp == NULL) {
 605                         /* file was closed whilst I/O was outstanding. Just
 606                          * ignore. */
 607                         DEBUG( 3,( "process_aio_queue: file closed whilst "
 608                                    "aio outstanding.\n"));
 609                         srv_cancel_sign_response(mid);
 610                         continue;
 611                 }
 612
 613                 if (!handle_aio_completed(aio_ex, &ret)) {
 614                         continue;
 615                 }
 616
 617                 delete_aio_ex(aio_ex);
 618         }
 619
 620         outstanding_aio_calls -= signals_received;
 621         signals_received = 0;
 622         BlockSignals(False, RT_SIGNAL_AIO);
 623         return ret;
 624 }
 625
 626 /****************************************************************************
 627  We're doing write behind and the client closed the file. Wait up to 30
 628  seconds (my arbitrary choice) for the aio to complete. Return 0 if all writes
 629  completed, errno to return if not.
 630 *****************************************************************************/
 631
 632 #define SMB_TIME_FOR_AIO_COMPLETE_WAIT 29
 633
 634 int wait_for_aio_completion(files_struct *fsp)
 635 {
 636         struct aio_extra *aio_ex;
 637         const SMB_STRUCT_AIOCB **aiocb_list;
 638         int aio_completion_count = 0;
 639         time_t start_time = time(NULL);
 640         int seconds_left;
 641
 642         for (seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT;
 643              seconds_left >= 0;) {
 644                 int err = 0;
 645                 int i;
 646                 struct timespec ts;
 647
 648                 aio_completion_count = 0;
 649                 for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 650                         if (aio_ex->fsp == fsp) {
 651                                 aio_completion_count++;
 652                         }
 653                 }
 654
 655                 if (!aio_completion_count) {
 656                         return 0;
 657                 }
 658
 659                 DEBUG(3,("wait_for_aio_completion: waiting for %d aio events "
 660                          "to complete.\n", aio_completion_count ));
 661
 662                 aiocb_list = SMB_MALLOC_ARRAY(const SMB_STRUCT_AIOCB *,
 663                                               aio_completion_count);
 664                 if (!aiocb_list) {
 665                         return ENOMEM;
 666                 }
 667
 668                 for( i = 0, aio_ex = aio_list_head;
 669                      aio_ex;
 670                      aio_ex = aio_ex->next) {
 671                         if (aio_ex->fsp == fsp) {
 672                                 aiocb_list[i++] = &aio_ex->acb;
 673                         }
 674                 }
 675
 676                 /* Now wait up to seconds_left for completion. */
 677                 ts.tv_sec = seconds_left;
 678                 ts.tv_nsec = 0;
 679
 680                 DEBUG(10,("wait_for_aio_completion: %d events, doing a wait "
 681                           "of %d seconds.\n",
 682                           aio_completion_count, seconds_left ));
 683
 684                 err = SMB_VFS_AIO_SUSPEND(fsp, aiocb_list,
 685                                           aio_completion_count, &ts);
 686
 687                 DEBUG(10,("wait_for_aio_completion: returned err = %d, "
 688                           "errno = %s\n", err, strerror(errno) ));
 689
 690                 if (err == -1 && errno == EAGAIN) {
 691                         DEBUG(0,("wait_for_aio_completion: aio_suspend timed "
 692                                  "out waiting for %d events after a wait of "
 693                                  "%d seconds\n", aio_completion_count,
 694                                  seconds_left));
 695                         /* Timeout. */
 696                         cancel_aio_by_fsp(fsp);
 697                         SAFE_FREE(aiocb_list);
 698                         return EIO;
 699                 }
 700
 701                 /* One or more events might have completed - process them if
 702                  * so. */
 703                 for( i = 0; i < aio_completion_count; i++) {
 704                         uint16 mid = aiocb_list[i]->aio_sigevent.sigev_value.sival_int;
 705
 706                         aio_ex = find_aio_ex(mid);
 707
 708                         if (!aio_ex) {
 709                                 DEBUG(0, ("wait_for_aio_completion: mid %u "
 710                                           "doesn't match an aio record\n",
 711                                           (unsigned int)mid ));
 712                                 continue;
 713                         }
 714
 715                         if (!handle_aio_completed(aio_ex, &err)) {
 716                                 continue;
 717                         }
 718                         delete_aio_ex(aio_ex);
 719                 }
 720
 721                 SAFE_FREE(aiocb_list);
 722                 seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT
 723                         - (time(NULL) - start_time);
 724         }
 725
 726         /* We timed out - we don't know why. Return ret if already an error,
 727          * else EIO. */
 728         DEBUG(10,("wait_for_aio_completion: aio_suspend timed out waiting "
 729                   "for %d events\n",
 730                   aio_completion_count));
 731
 732         return EIO;
 733 }
 734
 735 /****************************************************************************
 736  Cancel any outstanding aio requests. The client doesn't care about the reply.
 737 *****************************************************************************/
 738
 739 void cancel_aio_by_fsp(files_struct *fsp)
 740 {
 741         struct aio_extra *aio_ex;
 742
 743         for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 744                 if (aio_ex->fsp == fsp) {
 745                         /* Don't delete the aio_extra record as we may have
 746                            completed and don't yet know it. Just do the
 747                            aio_cancel call and return. */
 748                         SMB_VFS_AIO_CANCEL(fsp, &aio_ex->acb);
 749                         aio_ex->fsp = NULL; /* fsp will be closed when we
 750                                              * return. */
 751                 }
 752         }
 753 }
 754
 755 #else
 756 bool aio_finished(void)
 757 {
 758         return False;
 759 }
 760
 761 void initialize_async_io_handler(void)
 762 {
 763 }
 764
 765 int process_aio_queue(void)
 766 {
 767         return False;
 768 }
 769
 770 bool schedule_aio_read_and_X(connection_struct *conn,
 771                              struct smb_request *req,
 772                              files_struct *fsp, SMB_OFF_T startpos,
 773                              size_t smb_maxcnt)
 774 {
 775         return False;
 776 }
 777
 778 bool schedule_aio_write_and_X(connection_struct *conn,
 779                               struct smb_request *req,
 780                               files_struct *fsp, char *data,
 781                               SMB_OFF_T startpos,
 782                               size_t numtowrite)
 783 {
 784         return False;
 785 }
 786
 787 void cancel_aio_by_fsp(files_struct *fsp)
 788 {
 789 }
 790
 791 int wait_for_aio_completion(files_struct *fsp)
 792 {
 793         return ENOSYS;
 794 }
 795 #endif