source/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 2 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, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 #if defined(WITH_AIO)
  25
  26 /* The signal we'll use to signify aio done. */
  27 #ifndef RT_SIGNAL_AIO
  28 #define RT_SIGNAL_AIO (SIGRTMIN+3)
  29 #endif
  30
  31 /****************************************************************************
  32  The buffer we keep around whilst an aio request is in process.
  33 *****************************************************************************/
  34
  35 struct aio_extra {
  36         struct aio_extra *next, *prev;
  37         SMB_STRUCT_AIOCB acb;
  38         files_struct *fsp;
  39         BOOL read_req;
  40         uint16 mid;
  41         char *inbuf;
  42         char *outbuf;
  43 };
  44
  45 static struct aio_extra *aio_list_head;
  46
  47 /****************************************************************************
  48  Create the extended aio struct we must keep around for the lifetime
  49  of the aio_read call.
  50 *****************************************************************************/
  51
  52 static struct aio_extra *create_aio_ex_read(files_struct *fsp, size_t buflen,
  53                                             uint16 mid)
  54 {
  55         struct aio_extra *aio_ex = SMB_MALLOC_P(struct aio_extra);
  56
  57         if (!aio_ex) {
  58                 return NULL;
  59         }
  60         ZERO_STRUCTP(aio_ex);
  61         /* The output buffer stored in the aio_ex is the start of
  62            the smb return buffer. The buffer used in the acb
  63            is the start of the reply data portion of that buffer. */
  64         aio_ex->outbuf = SMB_MALLOC_ARRAY(char, buflen);
  65         if (!aio_ex->outbuf) {
  66                 SAFE_FREE(aio_ex);
  67                 return NULL;
  68         }
  69         DLIST_ADD(aio_list_head, aio_ex);
  70         aio_ex->fsp = fsp;
  71         aio_ex->read_req = True;
  72         aio_ex->mid = mid;
  73         return aio_ex;
  74 }
  75
  76 /****************************************************************************
  77  Create the extended aio struct we must keep around for the lifetime
  78  of the aio_write call.
  79 *****************************************************************************/
  80
  81 static struct aio_extra *create_aio_ex_write(files_struct *fsp,
  82                                              size_t inbuflen,
  83                                              size_t outbuflen,
  84                                              uint16 mid)
  85 {
  86         struct aio_extra *aio_ex = SMB_MALLOC_P(struct aio_extra);
  87
  88         if (!aio_ex) {
  89                 return NULL;
  90         }
  91         ZERO_STRUCTP(aio_ex);
  92
  93         /* We need space for an output reply of outbuflen bytes. */
  94         aio_ex->outbuf = SMB_MALLOC_ARRAY(char, outbuflen);
  95         if (!aio_ex->outbuf) {
  96                 SAFE_FREE(aio_ex);
  97                 return NULL;
  98         }
  99
 100         if (!(aio_ex->inbuf = SMB_MALLOC_ARRAY(char, inbuflen))) {
 101                 SAFE_FREE(aio_ex->outbuf);
 102                 SAFE_FREE(aio_ex);
 103                 return NULL;
 104         }
 105
 106         DLIST_ADD(aio_list_head, aio_ex);
 107         aio_ex->fsp = fsp;
 108         aio_ex->read_req = False;
 109         aio_ex->mid = mid;
 110         return aio_ex;
 111 }
 112
 113 /****************************************************************************
 114  Delete the extended aio struct.
 115 *****************************************************************************/
 116
 117 static void delete_aio_ex(struct aio_extra *aio_ex)
 118 {
 119         DLIST_REMOVE(aio_list_head, aio_ex);
 120         SAFE_FREE(aio_ex->inbuf);
 121         SAFE_FREE(aio_ex->outbuf);
 122         SAFE_FREE(aio_ex);
 123 }
 124
 125 /****************************************************************************
 126  Given the aiocb struct find the extended aio struct containing it.
 127 *****************************************************************************/
 128
 129 static struct aio_extra *find_aio_ex(uint16 mid)
 130 {
 131         struct aio_extra *p;
 132
 133         for( p = aio_list_head; p; p = p->next) {
 134                 if (mid == p->mid) {
 135                         return p;
 136                 }
 137         }
 138         return NULL;
 139 }
 140
 141 /****************************************************************************
 142  We can have these many aio buffers in flight.
 143 *****************************************************************************/
 144
 145 #define AIO_PENDING_SIZE 10
 146 static sig_atomic_t signals_received;
 147 static int outstanding_aio_calls;
 148 static uint16 aio_pending_array[AIO_PENDING_SIZE];
 149
 150 /****************************************************************************
 151  Signal handler when an aio request completes.
 152 *****************************************************************************/
 153
 154 static void signal_handler(int sig, siginfo_t *info, void *unused)
 155 {
 156         if (signals_received < AIO_PENDING_SIZE) {
 157                 aio_pending_array[signals_received] = info->si_value.sival_int;
 158                 signals_received++;
 159         } /* Else signal is lost. */
 160         sys_select_signal(RT_SIGNAL_AIO);
 161 }
 162
 163 /****************************************************************************
 164  Is there a signal waiting ?
 165 *****************************************************************************/
 166
 167 BOOL aio_finished(void)
 168 {
 169         return (signals_received != 0);
 170 }
 171
 172 /****************************************************************************
 173  Initialize the signal handler for aio read/write.
 174 *****************************************************************************/
 175
 176 void initialize_async_io_handler(void)
 177 {
 178         struct sigaction act;
 179
 180         ZERO_STRUCT(act);
 181         act.sa_sigaction = signal_handler;
 182         act.sa_flags = SA_SIGINFO;
 183         sigemptyset( &act.sa_mask );
 184         if (sigaction(RT_SIGNAL_AIO, &act, NULL) != 0) {
 185                 DEBUG(0,("Failed to setup RT_SIGNAL_AIO handler\n"));
 186         }
 187
 188         /* the signal can start off blocked due to a bug in bash */
 189         BlockSignals(False, RT_SIGNAL_AIO);
 190 }
 191
 192 /****************************************************************************
 193  Set up an aio request from a SMBreadX call.
 194 *****************************************************************************/
 195
 196 BOOL schedule_aio_read_and_X(connection_struct *conn,
 197                              char *inbuf, char *outbuf,
 198                              int length, int len_outbuf,
 199                              files_struct *fsp, SMB_OFF_T startpos,
 200                              size_t smb_maxcnt)
 201 {
 202         struct aio_extra *aio_ex;
 203         SMB_STRUCT_AIOCB *a;
 204         size_t bufsize;
 205         size_t min_aio_read_size = lp_aio_read_size(SNUM(conn));
 206
 207         if (!min_aio_read_size || (smb_maxcnt < min_aio_read_size)) {
 208                 /* Too small a read for aio request. */
 209                 DEBUG(10,("schedule_aio_read_and_X: read size (%u) too small "
 210                           "for minimum aio_read of %u\n",
 211                           (unsigned int)smb_maxcnt,
 212                           (unsigned int)min_aio_read_size ));
 213                 return False;
 214         }
 215
 216         /* Only do this on non-chained and non-chaining reads not using the
 217          * write cache. */
 218         if (chain_size !=0 || (CVAL(inbuf,smb_vwv0) != 0xFF)
 219             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 220                 return False;
 221         }
 222
 223         if (outstanding_aio_calls >= AIO_PENDING_SIZE) {
 224                 DEBUG(10,("schedule_aio_read_and_X: Already have %d aio "
 225                           "activities outstanding.\n",
 226                           outstanding_aio_calls ));
 227                 return False;
 228         }
 229
 230         /* The following is safe from integer wrap as we've already
 231            checked smb_maxcnt is 128k or less. */
 232         bufsize = PTR_DIFF(smb_buf(outbuf),outbuf) + smb_maxcnt;
 233
 234         if ((aio_ex = create_aio_ex_read(fsp, bufsize,
 235                                          SVAL(inbuf,smb_mid))) == NULL) {
 236                 DEBUG(10,("schedule_aio_read_and_X: malloc fail.\n"));
 237                 return False;
 238         }
 239
 240         /* Copy the SMB header already setup in outbuf. */
 241         memcpy(aio_ex->outbuf, outbuf, smb_buf(outbuf) - outbuf);
 242         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 243
 244         a = &aio_ex->acb;
 245
 246         /* Now set up the aio record for the read call. */
 247
 248         a->aio_fildes = fsp->fh->fd;
 249         a->aio_buf = smb_buf(aio_ex->outbuf);
 250         a->aio_nbytes = smb_maxcnt;
 251         a->aio_offset = startpos;
 252         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 253         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 254         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 255
 256         if (SMB_VFS_AIO_READ(fsp,a) == -1) {
 257                 DEBUG(0,("schedule_aio_read_and_X: aio_read failed. "
 258                          "Error %s\n", strerror(errno) ));
 259                 delete_aio_ex(aio_ex);
 260                 return False;
 261         }
 262
 263         DEBUG(10,("schedule_aio_read_and_X: scheduled aio_read for file %s, "
 264                   "offset %.0f, len = %u (mid = %u)\n",
 265                   fsp->fsp_name, (double)startpos, (unsigned int)smb_maxcnt,
 266                   (unsigned int)aio_ex->mid ));
 267
 268         srv_defer_sign_response(aio_ex->mid);
 269         outstanding_aio_calls++;
 270         return True;
 271 }
 272
 273 /****************************************************************************
 274  Set up an aio request from a SMBwriteX call.
 275 *****************************************************************************/
 276
 277 BOOL schedule_aio_write_and_X(connection_struct *conn,
 278                                 char *inbuf, char *outbuf,
 279                                 int length, int len_outbuf,
 280                                 files_struct *fsp, char *data,
 281                                 SMB_OFF_T startpos,
 282                                 size_t numtowrite)
 283 {
 284         struct aio_extra *aio_ex;
 285         SMB_STRUCT_AIOCB *a;
 286         size_t inbufsize, outbufsize;
 287         BOOL write_through = BITSETW(inbuf+smb_vwv7,0);
 288         size_t min_aio_write_size = lp_aio_write_size(SNUM(conn));
 289
 290         if (!min_aio_write_size || (numtowrite < min_aio_write_size)) {
 291                 /* Too small a write for aio request. */
 292                 DEBUG(10,("schedule_aio_write_and_X: write size (%u) too "
 293                           "small for minimum aio_write of %u\n",
 294                           (unsigned int)numtowrite,
 295                           (unsigned int)min_aio_write_size ));
 296                 return False;
 297         }
 298
 299         /* Only do this on non-chained and non-chaining reads not using the
 300          * write cache. */
 301         if (chain_size !=0 || (CVAL(inbuf,smb_vwv0) != 0xFF)
 302             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 303                 return False;
 304         }
 305
 306         if (outstanding_aio_calls >= AIO_PENDING_SIZE) {
 307                 DEBUG(3,("schedule_aio_write_and_X: Already have %d aio "
 308                          "activities outstanding.\n",
 309                           outstanding_aio_calls ));
 310                 DEBUG(10,("schedule_aio_write_and_X: failed to schedule "
 311                           "aio_write for file %s, offset %.0f, len = %u "
 312                           "(mid = %u)\n",
 313                           fsp->fsp_name, (double)startpos,
 314                           (unsigned int)numtowrite,
 315                           (unsigned int)SVAL(inbuf,smb_mid) ));
 316                 return False;
 317         }
 318
 319         inbufsize =  smb_len(inbuf) + 4;
 320         outbufsize = smb_len(outbuf) + 4;
 321         if (!(aio_ex = create_aio_ex_write(fsp, inbufsize, outbufsize,
 322                                            SVAL(inbuf,smb_mid)))) {
 323                 DEBUG(0,("schedule_aio_write_and_X: malloc fail.\n"));
 324                 return False;
 325         }
 326
 327         /* Copy the SMB header already setup in outbuf. */
 328         memcpy(aio_ex->inbuf, inbuf, inbufsize);
 329
 330         /* Copy the SMB header already setup in outbuf. */
 331         memcpy(aio_ex->outbuf, outbuf, outbufsize);
 332         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 333
 334         a = &aio_ex->acb;
 335
 336         /* Now set up the aio record for the write call. */
 337
 338         a->aio_fildes = fsp->fh->fd;
 339         a->aio_buf = aio_ex->inbuf + (PTR_DIFF(data, inbuf));
 340         a->aio_nbytes = numtowrite;
 341         a->aio_offset = startpos;
 342         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 343         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 344         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 345
 346         if (SMB_VFS_AIO_WRITE(fsp,a) == -1) {
 347                 DEBUG(3,("schedule_aio_wrote_and_X: aio_write failed. "
 348                          "Error %s\n", strerror(errno) ));
 349                 delete_aio_ex(aio_ex);
 350                 return False;
 351         }
 352
 353         if (!write_through && !lp_syncalways(SNUM(fsp->conn))
 354             && fsp->aio_write_behind) {
 355                 /* Lie to the client and immediately claim we finished the
 356                  * write. */
 357                 SSVAL(aio_ex->outbuf,smb_vwv2,numtowrite);
 358                 SSVAL(aio_ex->outbuf,smb_vwv4,(numtowrite>>16)&1);
 359                 show_msg(aio_ex->outbuf);
 360                 if (!send_smb(smbd_server_fd(),aio_ex->outbuf)) {
 361                         exit_server_cleanly("handle_aio_write: 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                 outsize = (UNIXERROR(ERRDOS,ERRnoaccess));
 412                 ret = errno;
 413         } else {
 414                 outsize = set_message(outbuf,12,nread,False);
 415                 SSVAL(outbuf,smb_vwv2,0xFFFF); /* Remaining - must be * -1. */
 416                 SSVAL(outbuf,smb_vwv5,nread);
 417                 SSVAL(outbuf,smb_vwv6,smb_offset(data,outbuf));
 418                 SSVAL(outbuf,smb_vwv7,((nread >> 16) & 1));
 419                 SSVAL(smb_buf(outbuf),-2,nread);
 420
 421                 DEBUG( 3, ( "handle_aio_read_complete file %s max=%d "
 422                             "nread=%d\n",
 423                             aio_ex->fsp->fsp_name,
 424                             aio_ex->acb.aio_nbytes, (int)nread ) );
 425
 426         }
 427         smb_setlen(outbuf,outsize - 4);
 428         show_msg(outbuf);
 429         if (!send_smb(smbd_server_fd(),outbuf)) {
 430                 exit_server_cleanly("handle_aio_read_complete: send_smb "
 431                                     "failed.");
 432         }
 433
 434         DEBUG(10,("handle_aio_read_complete: scheduled aio_read completed "
 435                   "for file %s, offset %.0f, len = %u\n",
 436                   aio_ex->fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 437                   (unsigned int)nread ));
 438
 439         return ret;
 440 }
 441
 442 /****************************************************************************
 443  Complete the write and return the data or error back to the client.
 444  Returns errno or zero if all ok.
 445 *****************************************************************************/
 446
 447 static int handle_aio_write_complete(struct aio_extra *aio_ex)
 448 {
 449         int ret = 0;
 450         files_struct *fsp = aio_ex->fsp;
 451         char *outbuf = aio_ex->outbuf;
 452         ssize_t numtowrite = aio_ex->acb.aio_nbytes;
 453         ssize_t nwritten = SMB_VFS_AIO_RETURN(fsp,&aio_ex->acb);
 454
 455         if (fsp->aio_write_behind) {
 456                 if (nwritten != numtowrite) {
 457                         if (nwritten == -1) {
 458                                 DEBUG(5,("handle_aio_write_complete: "
 459                                          "aio_write_behind failed ! File %s "
 460                                          "is corrupt ! Error %s\n",
 461                                          fsp->fsp_name, strerror(errno) ));
 462                                 ret = errno;
 463                         } else {
 464                                 DEBUG(0,("handle_aio_write_complete: "
 465                                          "aio_write_behind failed ! File %s "
 466                                          "is corrupt ! Wanted %u bytes but "
 467                                          "only wrote %d\n", fsp->fsp_name,
 468                                          (unsigned int)numtowrite,
 469                                          (int)nwritten ));
 470                                 ret = EIO;
 471                         }
 472                 } else {
 473                         DEBUG(10,("handle_aio_write_complete: "
 474                                   "aio_write_behind completed for file %s\n",
 475                                   fsp->fsp_name ));
 476                 }
 477                 return 0;
 478         }
 479
 480         /* We don't need outsize or set_message here as we've already set the
 481            fixed size length when we set up the aio call. */
 482
 483         if(nwritten == -1) {
 484                 DEBUG( 3,( "handle_aio_write: file %s wanted %u bytes. "
 485                            "nwritten == %d. Error = %s\n",
 486                            fsp->fsp_name, (unsigned int)numtowrite,
 487                            (int)nwritten, strerror(errno) ));
 488
 489                 /* If errno is ECANCELED then don't return anything to the
 490                  * client. */
 491                 if (errno == ECANCELED) {
 492                         srv_cancel_sign_response(aio_ex->mid);
 493                         return 0;
 494                 }
 495
 496                 UNIXERROR(ERRHRD,ERRdiskfull);
 497                 ret = errno;
 498         } else {
 499                 BOOL write_through = BITSETW(aio_ex->inbuf+smb_vwv7,0);
 500                 NTSTATUS status;
 501
 502                 SSVAL(outbuf,smb_vwv2,nwritten);
 503                 SSVAL(outbuf,smb_vwv4,(nwritten>>16)&1);
 504                 if (nwritten < (ssize_t)numtowrite) {
 505                         SCVAL(outbuf,smb_rcls,ERRHRD);
 506                         SSVAL(outbuf,smb_err,ERRdiskfull);
 507                 }
 508
 509                 DEBUG(3,("handle_aio_write: fnum=%d num=%d wrote=%d\n",
 510                          fsp->fnum, (int)numtowrite, (int)nwritten));
 511                 status = sync_file(fsp->conn,fsp, write_through);
 512                 if (!NT_STATUS_IS_OK(status)) {
 513                         UNIXERROR(ERRHRD,ERRdiskfull);
 514                         ret = errno;
 515                         DEBUG(5,("handle_aio_write: sync_file for %s returned %s\n",
 516                                 fsp->fsp_name, nt_errstr(status) ));
 517                 }
 518         }
 519
 520         show_msg(outbuf);
 521         if (!send_smb(smbd_server_fd(),outbuf)) {
 522                 exit_server_cleanly("handle_aio_write: send_smb failed.");
 523         }
 524
 525         DEBUG(10,("handle_aio_write_complete: scheduled aio_write completed "
 526                   "for file %s, offset %.0f, requested %u, written = %u\n",
 527                   fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 528                   (unsigned int)numtowrite, (unsigned int)nwritten ));
 529
 530         return ret;
 531 }
 532
 533 /****************************************************************************
 534  Handle any aio completion. Returns True if finished (and sets *perr if err
 535  was non-zero), False if not.
 536 *****************************************************************************/
 537
 538 static BOOL handle_aio_completed(struct aio_extra *aio_ex, int *perr)
 539 {
 540         int err;
 541
 542         /* Ensure the operation has really completed. */
 543         if (SMB_VFS_AIO_ERROR(aio_ex->fsp, &aio_ex->acb) == EINPROGRESS) {
 544                 DEBUG(10,( "handle_aio_completed: operation mid %u still in "
 545                            "process for file %s\n",
 546                            aio_ex->mid, aio_ex->fsp->fsp_name ));
 547                 return False;
 548         }
 549
 550         if (aio_ex->read_req) {
 551                 err = handle_aio_read_complete(aio_ex);
 552         } else {
 553                 err = handle_aio_write_complete(aio_ex);
 554         }
 555
 556         if (err) {
 557                 *perr = err; /* Only save non-zero errors. */
 558         }
 559
 560         return True;
 561 }
 562
 563 /****************************************************************************
 564  Handle any aio completion inline.
 565  Returns non-zero errno if fail or zero if all ok.
 566 *****************************************************************************/
 567
 568 int process_aio_queue(void)
 569 {
 570         int i;
 571         int ret = 0;
 572
 573         BlockSignals(True, RT_SIGNAL_AIO);
 574
 575         DEBUG(10,("process_aio_queue: signals_received = %d\n",
 576                   (int)signals_received));
 577         DEBUG(10,("process_aio_queue: outstanding_aio_calls = %d\n",
 578                   outstanding_aio_calls));
 579
 580         if (!signals_received) {
 581                 BlockSignals(False, RT_SIGNAL_AIO);
 582                 return 0;
 583         }
 584
 585         /* Drain all the complete aio_reads. */
 586         for (i = 0; i < signals_received; i++) {
 587                 uint16 mid = aio_pending_array[i];
 588                 files_struct *fsp = NULL;
 589                 struct aio_extra *aio_ex = find_aio_ex(mid);
 590
 591                 if (!aio_ex) {
 592                         DEBUG(3,("process_aio_queue: Can't find record to "
 593                                  "match mid %u.\n", (unsigned int)mid));
 594                         srv_cancel_sign_response(mid);
 595                         continue;
 596                 }
 597
 598                 fsp = aio_ex->fsp;
 599                 if (fsp == NULL) {
 600                         /* file was closed whilst I/O was outstanding. Just
 601                          * ignore. */
 602                         DEBUG( 3,( "process_aio_queue: file closed whilst "
 603                                    "aio outstanding.\n"));
 604                         srv_cancel_sign_response(mid);
 605                         continue;
 606                 }
 607
 608                 if (!handle_aio_completed(aio_ex, &ret)) {
 609                         continue;
 610                 }
 611
 612                 delete_aio_ex(aio_ex);
 613         }
 614
 615         outstanding_aio_calls -= signals_received;
 616         signals_received = 0;
 617         BlockSignals(False, RT_SIGNAL_AIO);
 618         return ret;
 619 }
 620
 621 /****************************************************************************
 622  We're doing write behind and the client closed the file. Wait up to 30
 623  seconds (my arbitrary choice) for the aio to complete. Return 0 if all writes
 624  completed, errno to return if not.
 625 *****************************************************************************/
 626
 627 #define SMB_TIME_FOR_AIO_COMPLETE_WAIT 29
 628
 629 int wait_for_aio_completion(files_struct *fsp)
 630 {
 631         struct aio_extra *aio_ex;
 632         const SMB_STRUCT_AIOCB **aiocb_list;
 633         int aio_completion_count = 0;
 634         time_t start_time = time(NULL);
 635         int seconds_left;
 636
 637         for (seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT;
 638              seconds_left >= 0;) {
 639                 int err = 0;
 640                 int i;
 641                 struct timespec ts;
 642
 643                 aio_completion_count = 0;
 644                 for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 645                         if (aio_ex->fsp == fsp) {
 646                                 aio_completion_count++;
 647                         }
 648                 }
 649
 650                 if (!aio_completion_count) {
 651                         return 0;
 652                 }
 653
 654                 DEBUG(3,("wait_for_aio_completion: waiting for %d aio events "
 655                          "to complete.\n", aio_completion_count ));
 656
 657                 aiocb_list = SMB_MALLOC_ARRAY(const SMB_STRUCT_AIOCB *,
 658                                               aio_completion_count);
 659                 if (!aiocb_list) {
 660                         return ENOMEM;
 661                 }
 662
 663                 for( i = 0, aio_ex = aio_list_head;
 664                      aio_ex;
 665                      aio_ex = aio_ex->next) {
 666                         if (aio_ex->fsp == fsp) {
 667                                 aiocb_list[i++] = &aio_ex->acb;
 668                         }
 669                 }
 670
 671                 /* Now wait up to seconds_left for completion. */
 672                 ts.tv_sec = seconds_left;
 673                 ts.tv_nsec = 0;
 674
 675                 DEBUG(10,("wait_for_aio_completion: %d events, doing a wait "
 676                           "of %d seconds.\n",
 677                           aio_completion_count, seconds_left ));
 678
 679                 err = SMB_VFS_AIO_SUSPEND(fsp, aiocb_list,
 680                                           aio_completion_count, &ts);
 681
 682                 DEBUG(10,("wait_for_aio_completion: returned err = %d, "
 683                           "errno = %s\n", err, strerror(errno) ));
 684
 685                 if (err == -1 && errno == EAGAIN) {
 686                         DEBUG(0,("wait_for_aio_completion: aio_suspend timed "
 687                                  "out waiting for %d events after a wait of "
 688                                  "%d seconds\n", aio_completion_count,
 689                                  seconds_left));
 690                         /* Timeout. */
 691                         cancel_aio_by_fsp(fsp);
 692                         SAFE_FREE(aiocb_list);
 693                         return EIO;
 694                 }
 695
 696                 /* One or more events might have completed - process them if
 697                  * so. */
 698                 for( i = 0; i < aio_completion_count; i++) {
 699                         uint16 mid = aiocb_list[i]->aio_sigevent.sigev_value.sival_int;
 700
 701                         aio_ex = find_aio_ex(mid);
 702
 703                         if (!aio_ex) {
 704                                 DEBUG(0, ("wait_for_aio_completion: mid %u "
 705                                           "doesn't match an aio record\n",
 706                                           (unsigned int)mid ));
 707                                 continue;
 708                         }
 709
 710                         if (!handle_aio_completed(aio_ex, &err)) {
 711                                 continue;
 712                         }
 713                         delete_aio_ex(aio_ex);
 714                 }
 715
 716                 SAFE_FREE(aiocb_list);
 717                 seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT
 718                         - (time(NULL) - start_time);
 719         }
 720
 721         /* We timed out - we don't know why. Return ret if already an error,
 722          * else EIO. */
 723         DEBUG(10,("wait_for_aio_completion: aio_suspend timed out waiting "
 724                   "for %d events\n",
 725                   aio_completion_count));
 726
 727         return EIO;
 728 }
 729
 730 /****************************************************************************
 731  Cancel any outstanding aio requests. The client doesn't care about the reply.
 732 *****************************************************************************/
 733
 734 void cancel_aio_by_fsp(files_struct *fsp)
 735 {
 736         struct aio_extra *aio_ex;
 737
 738         for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 739                 if (aio_ex->fsp == fsp) {
 740                         /* Don't delete the aio_extra record as we may have
 741                            completed and don't yet know it. Just do the
 742                            aio_cancel call and return. */
 743                         SMB_VFS_AIO_CANCEL(fsp,fsp->fh->fd, &aio_ex->acb);
 744                         aio_ex->fsp = NULL; /* fsp will be closed when we
 745                                              * return. */
 746                 }
 747         }
 748 }
 749
 750 #else
 751 BOOL aio_finished(void)
 752 {
 753         return False;
 754 }
 755
 756 void initialize_async_io_handler(void)
 757 {
 758 }
 759
 760 int process_aio_queue(void)
 761 {
 762         return False;
 763 }
 764
 765 BOOL schedule_aio_read_and_X(connection_struct *conn,
 766                              char *inbuf, char *outbuf,
 767                              int length, int len_outbuf,
 768                              files_struct *fsp, SMB_OFF_T startpos,
 769                              size_t smb_maxcnt)
 770 {
 771         return False;
 772 }
 773
 774 BOOL schedule_aio_write_and_X(connection_struct *conn,
 775                                 char *inbuf, char *outbuf,
 776                                 int length, int len_outbuf,
 777                                 files_struct *fsp, char *data,
 778                                 SMB_OFF_T startpos,
 779                                 size_t numtowrite)
 780 {
 781         return False;
 782 }
 783
 784 void cancel_aio_by_fsp(files_struct *fsp)
 785 {
 786 }
 787
 788 BOOL wait_for_aio_completion(files_struct *fsp)
 789 {
 790         return True;
 791 }
 792 #endif