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 static int aio_pending_size;
 145 static sig_atomic_t signals_received;
 146 static int outstanding_aio_calls;
 147 static uint16 *aio_pending_array;
 148
 149 /****************************************************************************
 150  Signal handler when an aio request completes.
 151 *****************************************************************************/
 152
 153 void aio_request_done(uint16_t mid)
 154 {
 155         if (signals_received < aio_pending_size) {
 156                 aio_pending_array[signals_received] = mid;
 157                 signals_received++;
 158         }
 159         /* Else signal is lost. */
 160 }
 161
 162 static void signal_handler(int sig, siginfo_t *info, void *unused)
 163 {
 164         aio_request_done(info->si_value.sival_int);
 165         sys_select_signal(RT_SIGNAL_AIO);
 166 }
 167
 168 /****************************************************************************
 169  Is there a signal waiting ?
 170 *****************************************************************************/
 171
 172 bool aio_finished(void)
 173 {
 174         return (signals_received != 0);
 175 }
 176
 177 /****************************************************************************
 178  Initialize the signal handler for aio read/write.
 179 *****************************************************************************/
 180
 181 void initialize_async_io_handler(void)
 182 {
 183         struct sigaction act;
 184
 185         aio_pending_size = lp_maxmux();
 186         aio_pending_array = SMB_MALLOC_ARRAY(uint16, aio_pending_size);
 187         SMB_ASSERT(aio_pending_array != NULL);
 188
 189         ZERO_STRUCT(act);
 190         act.sa_sigaction = signal_handler;
 191         act.sa_flags = SA_SIGINFO;
 192         sigemptyset( &act.sa_mask );
 193         if (sigaction(RT_SIGNAL_AIO, &act, NULL) != 0) {
 194                 DEBUG(0,("Failed to setup RT_SIGNAL_AIO handler\n"));
 195         }
 196
 197         /* the signal can start off blocked due to a bug in bash */
 198         BlockSignals(False, RT_SIGNAL_AIO);
 199 }
 200
 201 /****************************************************************************
 202  Set up an aio request from a SMBreadX call.
 203 *****************************************************************************/
 204
 205 bool schedule_aio_read_and_X(connection_struct *conn,
 206                              struct smb_request *req,
 207                              files_struct *fsp, SMB_OFF_T startpos,
 208                              size_t smb_maxcnt)
 209 {
 210         struct aio_extra *aio_ex;
 211         SMB_STRUCT_AIOCB *a;
 212         size_t bufsize;
 213         size_t min_aio_read_size = lp_aio_read_size(SNUM(conn));
 214
 215         if (fsp->base_fsp != NULL) {
 216                 /* No AIO on streams yet */
 217                 DEBUG(10, ("AIO on streams not yet supported\n"));
 218                 return false;
 219         }
 220
 221         if ((!min_aio_read_size || (smb_maxcnt < min_aio_read_size))
 222             && !SMB_VFS_AIO_FORCE(fsp)) {
 223                 /* Too small a read for aio request. */
 224                 DEBUG(10,("schedule_aio_read_and_X: read size (%u) too small "
 225                           "for minimum aio_read of %u\n",
 226                           (unsigned int)smb_maxcnt,
 227                           (unsigned int)min_aio_read_size ));
 228                 return False;
 229         }
 230
 231         /* Only do this on non-chained and non-chaining reads not using the
 232          * write cache. */
 233         if (chain_size !=0 || (CVAL(req->inbuf,smb_vwv0) != 0xFF)
 234             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 235                 return False;
 236         }
 237
 238         if (outstanding_aio_calls >= aio_pending_size) {
 239                 DEBUG(10,("schedule_aio_read_and_X: Already have %d aio "
 240                           "activities outstanding.\n",
 241                           outstanding_aio_calls ));
 242                 return False;
 243         }
 244
 245         /* The following is safe from integer wrap as we've already checked
 246            smb_maxcnt is 128k or less. Wct is 12 for read replies */
 247
 248         bufsize = smb_size + 12 * 2 + smb_maxcnt;
 249
 250         if ((aio_ex = create_aio_ex_read(fsp, bufsize, req->mid)) == NULL) {
 251                 DEBUG(10,("schedule_aio_read_and_X: malloc fail.\n"));
 252                 return False;
 253         }
 254
 255         construct_reply_common((char *)req->inbuf, aio_ex->outbuf);
 256         srv_set_message(aio_ex->outbuf, 12, 0, True);
 257         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 258
 259         a = &aio_ex->acb;
 260
 261         /* Now set up the aio record for the read call. */
 262
 263         a->aio_fildes = fsp->fh->fd;
 264         a->aio_buf = smb_buf(aio_ex->outbuf);
 265         a->aio_nbytes = smb_maxcnt;
 266         a->aio_offset = startpos;
 267         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 268         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 269         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 270
 271         become_root();
 272         if (SMB_VFS_AIO_READ(fsp,a) == -1) {
 273                 DEBUG(0,("schedule_aio_read_and_X: aio_read failed. "
 274                          "Error %s\n", strerror(errno) ));
 275                 delete_aio_ex(aio_ex);
 276                 unbecome_root();
 277                 return False;
 278         }
 279         unbecome_root();
 280
 281         DEBUG(10,("schedule_aio_read_and_X: scheduled aio_read for file %s, "
 282                   "offset %.0f, len = %u (mid = %u)\n",
 283                   fsp->fsp_name, (double)startpos, (unsigned int)smb_maxcnt,
 284                   (unsigned int)aio_ex->mid ));
 285
 286         srv_defer_sign_response(aio_ex->mid);
 287         outstanding_aio_calls++;
 288         return True;
 289 }
 290
 291 /****************************************************************************
 292  Set up an aio request from a SMBwriteX call.
 293 *****************************************************************************/
 294
 295 bool schedule_aio_write_and_X(connection_struct *conn,
 296                               struct smb_request *req,
 297                               files_struct *fsp, char *data,
 298                               SMB_OFF_T startpos,
 299                               size_t numtowrite)
 300 {
 301         struct aio_extra *aio_ex;
 302         SMB_STRUCT_AIOCB *a;
 303         size_t inbufsize, outbufsize;
 304         bool write_through = BITSETW(req->inbuf+smb_vwv7,0);
 305         size_t min_aio_write_size = lp_aio_write_size(SNUM(conn));
 306
 307         if (fsp->base_fsp != NULL) {
 308                 /* No AIO on streams yet */
 309                 DEBUG(10, ("AIO on streams not yet supported\n"));
 310                 return false;
 311         }
 312
 313         if ((!min_aio_write_size || (numtowrite < min_aio_write_size))
 314             && !SMB_VFS_AIO_FORCE(fsp)) {
 315                 /* Too small a write for aio request. */
 316                 DEBUG(10,("schedule_aio_write_and_X: write size (%u) too "
 317                           "small for minimum aio_write of %u\n",
 318                           (unsigned int)numtowrite,
 319                           (unsigned int)min_aio_write_size ));
 320                 return False;
 321         }
 322
 323         /* Only do this on non-chained and non-chaining reads not using the
 324          * write cache. */
 325         if (chain_size !=0 || (CVAL(req->inbuf,smb_vwv0) != 0xFF)
 326             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 327                 return False;
 328         }
 329
 330         if (outstanding_aio_calls >= aio_pending_size) {
 331                 DEBUG(3,("schedule_aio_write_and_X: Already have %d aio "
 332                          "activities outstanding.\n",
 333                           outstanding_aio_calls ));
 334                 DEBUG(10,("schedule_aio_write_and_X: failed to schedule "
 335                           "aio_write for file %s, offset %.0f, len = %u "
 336                           "(mid = %u)\n",
 337                           fsp->fsp_name, (double)startpos,
 338                           (unsigned int)numtowrite,
 339                           (unsigned int)req->mid ));
 340                 return False;
 341         }
 342
 343         inbufsize =  smb_len(req->inbuf) + 4;
 344         reply_outbuf(req, 6, 0);
 345         outbufsize = smb_len(req->outbuf) + 4;
 346         if (!(aio_ex = create_aio_ex_write(fsp, inbufsize, outbufsize,
 347                                            req->mid))) {
 348                 DEBUG(0,("schedule_aio_write_and_X: malloc fail.\n"));
 349                 return False;
 350         }
 351
 352         /* Copy the SMB header already setup in outbuf. */
 353         memcpy(aio_ex->inbuf, req->inbuf, inbufsize);
 354
 355         /* Copy the SMB header already setup in outbuf. */
 356         memcpy(aio_ex->outbuf, req->outbuf, outbufsize);
 357         TALLOC_FREE(req->outbuf);
 358         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 359
 360         a = &aio_ex->acb;
 361
 362         /* Now set up the aio record for the write call. */
 363
 364         a->aio_fildes = fsp->fh->fd;
 365         a->aio_buf = aio_ex->inbuf + (PTR_DIFF(data, req->inbuf));
 366         a->aio_nbytes = numtowrite;
 367         a->aio_offset = startpos;
 368         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 369         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 370         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 371
 372         become_root();
 373         if (SMB_VFS_AIO_WRITE(fsp,a) == -1) {
 374                 DEBUG(3,("schedule_aio_wrote_and_X: aio_write failed. "
 375                          "Error %s\n", strerror(errno) ));
 376                 delete_aio_ex(aio_ex);
 377                 unbecome_root();
 378                 return False;
 379         }
 380         unbecome_root();
 381
 382         release_level_2_oplocks_on_change(fsp);
 383
 384         if (!write_through && !lp_syncalways(SNUM(fsp->conn))
 385             && fsp->aio_write_behind) {
 386                 /* Lie to the client and immediately claim we finished the
 387                  * write. */
 388                 SSVAL(aio_ex->outbuf,smb_vwv2,numtowrite);
 389                 SSVAL(aio_ex->outbuf,smb_vwv4,(numtowrite>>16)&1);
 390                 show_msg(aio_ex->outbuf);
 391                 if (!srv_send_smb(smbd_server_fd(),aio_ex->outbuf,
 392                                 IS_CONN_ENCRYPTED(fsp->conn))) {
 393                         exit_server_cleanly("handle_aio_write: srv_send_smb "
 394                                             "failed.");
 395                 }
 396                 DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write "
 397                           "behind for file %s\n", fsp->fsp_name ));
 398         } else {
 399                 srv_defer_sign_response(aio_ex->mid);
 400         }
 401         outstanding_aio_calls++;
 402
 403         DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write for file "
 404                   "%s, offset %.0f, len = %u (mid = %u) "
 405                   "outstanding_aio_calls = %d\n",
 406                   fsp->fsp_name, (double)startpos, (unsigned int)numtowrite,
 407                   (unsigned int)aio_ex->mid, outstanding_aio_calls ));
 408
 409         return True;
 410 }
 411
 412
 413 /****************************************************************************
 414  Complete the read and return the data or error back to the client.
 415  Returns errno or zero if all ok.
 416 *****************************************************************************/
 417
 418 static int handle_aio_read_complete(struct aio_extra *aio_ex)
 419 {
 420         int ret = 0;
 421         int outsize;
 422         char *outbuf = aio_ex->outbuf;
 423         char *data = smb_buf(outbuf);
 424         ssize_t nread = SMB_VFS_AIO_RETURN(aio_ex->fsp,&aio_ex->acb);
 425
 426         if (nread < 0) {
 427                 /* We're relying here on the fact that if the fd is
 428                    closed then the aio will complete and aio_return
 429                    will return an error. Hopefully this is
 430                    true.... JRA. */
 431
 432                 /* If errno is ECANCELED then don't return anything to the
 433                  * client. */
 434                 if (errno == ECANCELED) {
 435                         srv_cancel_sign_response(aio_ex->mid);
 436                         return 0;
 437                 }
 438
 439                 DEBUG( 3,( "handle_aio_read_complete: file %s nread == -1. "
 440                            "Error = %s\n",
 441                            aio_ex->fsp->fsp_name, strerror(errno) ));
 442
 443                 ret = errno;
 444                 ERROR_NT(map_nt_error_from_unix(ret));
 445                 outsize = srv_set_message(outbuf,0,0,true);
 446         } else {
 447                 outsize = srv_set_message(outbuf,12,nread,False);
 448                 SSVAL(outbuf,smb_vwv2,0xFFFF); /* Remaining - must be * -1. */
 449                 SSVAL(outbuf,smb_vwv5,nread);
 450                 SSVAL(outbuf,smb_vwv6,smb_offset(data,outbuf));
 451                 SSVAL(outbuf,smb_vwv7,((nread >> 16) & 1));
 452                 SSVAL(smb_buf(outbuf),-2,nread);
 453
 454                 aio_ex->fsp->fh->pos = aio_ex->acb.aio_offset + nread;
 455                 aio_ex->fsp->fh->position_information = aio_ex->fsp->fh->pos;
 456
 457                 DEBUG( 3, ( "handle_aio_read_complete file %s max=%d "
 458                             "nread=%d\n",
 459                             aio_ex->fsp->fsp_name,
 460                             (int)aio_ex->acb.aio_nbytes, (int)nread ) );
 461
 462         }
 463         smb_setlen(outbuf,outsize - 4);
 464         show_msg(outbuf);
 465         if (!srv_send_smb(smbd_server_fd(),outbuf,
 466                         IS_CONN_ENCRYPTED(aio_ex->fsp->conn))) {
 467                 exit_server_cleanly("handle_aio_read_complete: srv_send_smb "
 468                                     "failed.");
 469         }
 470
 471         DEBUG(10,("handle_aio_read_complete: scheduled aio_read completed "
 472                   "for file %s, offset %.0f, len = %u\n",
 473                   aio_ex->fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 474                   (unsigned int)nread ));
 475
 476         return ret;
 477 }
 478
 479 /****************************************************************************
 480  Complete the write and return the data or error back to the client.
 481  Returns errno or zero if all ok.
 482 *****************************************************************************/
 483
 484 static int handle_aio_write_complete(struct aio_extra *aio_ex)
 485 {
 486         int ret = 0;
 487         files_struct *fsp = aio_ex->fsp;
 488         char *outbuf = aio_ex->outbuf;
 489         ssize_t numtowrite = aio_ex->acb.aio_nbytes;
 490         ssize_t nwritten = SMB_VFS_AIO_RETURN(fsp,&aio_ex->acb);
 491
 492         if (fsp->aio_write_behind) {
 493                 if (nwritten != numtowrite) {
 494                         if (nwritten == -1) {
 495                                 DEBUG(5,("handle_aio_write_complete: "
 496                                          "aio_write_behind failed ! File %s "
 497                                          "is corrupt ! Error %s\n",
 498                                          fsp->fsp_name, strerror(errno) ));
 499                                 ret = errno;
 500                         } else {
 501                                 DEBUG(0,("handle_aio_write_complete: "
 502                                          "aio_write_behind failed ! File %s "
 503                                          "is corrupt ! Wanted %u bytes but "
 504                                          "only wrote %d\n", fsp->fsp_name,
 505                                          (unsigned int)numtowrite,
 506                                          (int)nwritten ));
 507                                 ret = EIO;
 508                         }
 509                 } else {
 510                         DEBUG(10,("handle_aio_write_complete: "
 511                                   "aio_write_behind completed for file %s\n",
 512                                   fsp->fsp_name ));
 513                 }
 514                 return 0;
 515         }
 516
 517         /* We don't need outsize or set_message here as we've already set the
 518            fixed size length when we set up the aio call. */
 519
 520         if(nwritten == -1) {
 521                 DEBUG( 3,( "handle_aio_write: file %s wanted %u bytes. "
 522                            "nwritten == %d. Error = %s\n",
 523                            fsp->fsp_name, (unsigned int)numtowrite,
 524                            (int)nwritten, strerror(errno) ));
 525
 526                 /* If errno is ECANCELED then don't return anything to the
 527                  * client. */
 528                 if (errno == ECANCELED) {
 529                         srv_cancel_sign_response(aio_ex->mid);
 530                         return 0;
 531                 }
 532
 533                 ret = errno;
 534                 ERROR_BOTH(map_nt_error_from_unix(ret), ERRHRD, ERRdiskfull);
 535                 srv_set_message(outbuf,0,0,true);
 536         } else {
 537                 bool write_through = BITSETW(aio_ex->inbuf+smb_vwv7,0);
 538                 NTSTATUS status;
 539
 540                 SSVAL(outbuf,smb_vwv2,nwritten);
 541                 SSVAL(outbuf,smb_vwv4,(nwritten>>16)&1);
 542                 if (nwritten < (ssize_t)numtowrite) {
 543                         SCVAL(outbuf,smb_rcls,ERRHRD);
 544                         SSVAL(outbuf,smb_err,ERRdiskfull);
 545                 }
 546
 547                 DEBUG(3,("handle_aio_write: fnum=%d num=%d wrote=%d\n",
 548                          fsp->fnum, (int)numtowrite, (int)nwritten));
 549                 status = sync_file(fsp->conn,fsp, write_through);
 550                 if (!NT_STATUS_IS_OK(status)) {
 551                         ret = errno;
 552                         ERROR_BOTH(map_nt_error_from_unix(ret),
 553                                    ERRHRD, ERRdiskfull);
 554                         srv_set_message(outbuf,0,0,true);
 555                         DEBUG(5,("handle_aio_write: sync_file for %s returned %s\n",
 556                                 fsp->fsp_name, nt_errstr(status) ));
 557                 }
 558
 559                 aio_ex->fsp->fh->pos = aio_ex->acb.aio_offset + nwritten;
 560         }
 561
 562         show_msg(outbuf);
 563         if (!srv_send_smb(smbd_server_fd(),outbuf,IS_CONN_ENCRYPTED(fsp->conn))) {
 564                 exit_server_cleanly("handle_aio_write: srv_send_smb failed.");
 565         }
 566
 567         DEBUG(10,("handle_aio_write_complete: scheduled aio_write completed "
 568                   "for file %s, offset %.0f, requested %u, written = %u\n",
 569                   fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 570                   (unsigned int)numtowrite, (unsigned int)nwritten ));
 571
 572         return ret;
 573 }
 574
 575 /****************************************************************************
 576  Handle any aio completion. Returns True if finished (and sets *perr if err
 577  was non-zero), False if not.
 578 *****************************************************************************/
 579
 580 static bool handle_aio_completed(struct aio_extra *aio_ex, int *perr)
 581 {
 582         int err;
 583
 584         /* Ensure the operation has really completed. */
 585         if (SMB_VFS_AIO_ERROR(aio_ex->fsp, &aio_ex->acb) == EINPROGRESS) {
 586                 DEBUG(10,( "handle_aio_completed: operation mid %u still in "
 587                            "process for file %s\n",
 588                            aio_ex->mid, aio_ex->fsp->fsp_name ));
 589                 return False;
 590         }
 591
 592         if (aio_ex->read_req) {
 593                 err = handle_aio_read_complete(aio_ex);
 594         } else {
 595                 err = handle_aio_write_complete(aio_ex);
 596         }
 597
 598         if (err) {
 599                 *perr = err; /* Only save non-zero errors. */
 600         }
 601
 602         return True;
 603 }
 604
 605 /****************************************************************************
 606  Handle any aio completion inline.
 607  Returns non-zero errno if fail or zero if all ok.
 608 *****************************************************************************/
 609
 610 int process_aio_queue(void)
 611 {
 612         int i;
 613         int ret = 0;
 614
 615         BlockSignals(True, RT_SIGNAL_AIO);
 616
 617         DEBUG(10,("process_aio_queue: signals_received = %d\n",
 618                   (int)signals_received));
 619         DEBUG(10,("process_aio_queue: outstanding_aio_calls = %d\n",
 620                   outstanding_aio_calls));
 621
 622         if (!signals_received) {
 623                 BlockSignals(False, RT_SIGNAL_AIO);
 624                 return 0;
 625         }
 626
 627         /* Drain all the complete aio_reads. */
 628         for (i = 0; i < signals_received; i++) {
 629                 uint16 mid = aio_pending_array[i];
 630                 files_struct *fsp = NULL;
 631                 struct aio_extra *aio_ex = find_aio_ex(mid);
 632
 633                 if (!aio_ex) {
 634                         DEBUG(3,("process_aio_queue: Can't find record to "
 635                                  "match mid %u.\n", (unsigned int)mid));
 636                         srv_cancel_sign_response(mid);
 637                         continue;
 638                 }
 639
 640                 fsp = aio_ex->fsp;
 641                 if (fsp == NULL) {
 642                         /* file was closed whilst I/O was outstanding. Just
 643                          * ignore. */
 644                         DEBUG( 3,( "process_aio_queue: file closed whilst "
 645                                    "aio outstanding.\n"));
 646                         srv_cancel_sign_response(mid);
 647                         continue;
 648                 }
 649
 650                 if (!handle_aio_completed(aio_ex, &ret)) {
 651                         continue;
 652                 }
 653
 654                 delete_aio_ex(aio_ex);
 655         }
 656
 657         outstanding_aio_calls -= signals_received;
 658         signals_received = 0;
 659         BlockSignals(False, RT_SIGNAL_AIO);
 660         return ret;
 661 }
 662
 663 /****************************************************************************
 664  We're doing write behind and the client closed the file. Wait up to 30
 665  seconds (my arbitrary choice) for the aio to complete. Return 0 if all writes
 666  completed, errno to return if not.
 667 *****************************************************************************/
 668
 669 #define SMB_TIME_FOR_AIO_COMPLETE_WAIT 29
 670
 671 int wait_for_aio_completion(files_struct *fsp)
 672 {
 673         struct aio_extra *aio_ex;
 674         const SMB_STRUCT_AIOCB **aiocb_list;
 675         int aio_completion_count = 0;
 676         time_t start_time = time(NULL);
 677         int seconds_left;
 678
 679         for (seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT;
 680              seconds_left >= 0;) {
 681                 int err = 0;
 682                 int i;
 683                 struct timespec ts;
 684
 685                 aio_completion_count = 0;
 686                 for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 687                         if (aio_ex->fsp == fsp) {
 688                                 aio_completion_count++;
 689                         }
 690                 }
 691
 692                 if (!aio_completion_count) {
 693                         return 0;
 694                 }
 695
 696                 DEBUG(3,("wait_for_aio_completion: waiting for %d aio events "
 697                          "to complete.\n", aio_completion_count ));
 698
 699                 aiocb_list = SMB_MALLOC_ARRAY(const SMB_STRUCT_AIOCB *,
 700                                               aio_completion_count);
 701                 if (!aiocb_list) {
 702                         return ENOMEM;
 703                 }
 704
 705                 for( i = 0, aio_ex = aio_list_head;
 706                      aio_ex;
 707                      aio_ex = aio_ex->next) {
 708                         if (aio_ex->fsp == fsp) {
 709                                 aiocb_list[i++] = &aio_ex->acb;
 710                         }
 711                 }
 712
 713                 /* Now wait up to seconds_left for completion. */
 714                 ts.tv_sec = seconds_left;
 715                 ts.tv_nsec = 0;
 716
 717                 DEBUG(10,("wait_for_aio_completion: %d events, doing a wait "
 718                           "of %d seconds.\n",
 719                           aio_completion_count, seconds_left ));
 720
 721                 err = SMB_VFS_AIO_SUSPEND(fsp, aiocb_list,
 722                                           aio_completion_count, &ts);
 723
 724                 DEBUG(10,("wait_for_aio_completion: returned err = %d, "
 725                           "errno = %s\n", err, strerror(errno) ));
 726
 727                 if (err == -1 && errno == EAGAIN) {
 728                         DEBUG(0,("wait_for_aio_completion: aio_suspend timed "
 729                                  "out waiting for %d events after a wait of "
 730                                  "%d seconds\n", aio_completion_count,
 731                                  seconds_left));
 732                         /* Timeout. */
 733                         cancel_aio_by_fsp(fsp);
 734                         SAFE_FREE(aiocb_list);
 735                         return EIO;
 736                 }
 737
 738                 /* One or more events might have completed - process them if
 739                  * so. */
 740                 for( i = 0; i < aio_completion_count; i++) {
 741                         uint16 mid = aiocb_list[i]->aio_sigevent.sigev_value.sival_int;
 742
 743                         aio_ex = find_aio_ex(mid);
 744
 745                         if (!aio_ex) {
 746                                 DEBUG(0, ("wait_for_aio_completion: mid %u "
 747                                           "doesn't match an aio record\n",
 748                                           (unsigned int)mid ));
 749                                 continue;
 750                         }
 751
 752                         if (!handle_aio_completed(aio_ex, &err)) {
 753                                 continue;
 754                         }
 755                         delete_aio_ex(aio_ex);
 756                 }
 757
 758                 SAFE_FREE(aiocb_list);
 759                 seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT
 760                         - (time(NULL) - start_time);
 761         }
 762
 763         /* We timed out - we don't know why. Return ret if already an error,
 764          * else EIO. */
 765         DEBUG(10,("wait_for_aio_completion: aio_suspend timed out waiting "
 766                   "for %d events\n",
 767                   aio_completion_count));
 768
 769         return EIO;
 770 }
 771
 772 /****************************************************************************
 773  Cancel any outstanding aio requests. The client doesn't care about the reply.
 774 *****************************************************************************/
 775
 776 void cancel_aio_by_fsp(files_struct *fsp)
 777 {
 778         struct aio_extra *aio_ex;
 779
 780         for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 781                 if (aio_ex->fsp == fsp) {
 782                         /* Don't delete the aio_extra record as we may have
 783                            completed and don't yet know it. Just do the
 784                            aio_cancel call and return. */
 785                         SMB_VFS_AIO_CANCEL(fsp, &aio_ex->acb);
 786                         aio_ex->fsp = NULL; /* fsp will be closed when we
 787                                              * return. */
 788                 }
 789         }
 790 }
 791
 792 #else
 793 bool aio_finished(void)
 794 {
 795         return False;
 796 }
 797
 798 void initialize_async_io_handler(void)
 799 {
 800 }
 801
 802 int process_aio_queue(void)
 803 {
 804         return False;
 805 }
 806
 807 bool schedule_aio_read_and_X(connection_struct *conn,
 808                              struct smb_request *req,
 809                              files_struct *fsp, SMB_OFF_T startpos,
 810                              size_t smb_maxcnt)
 811 {
 812         return False;
 813 }
 814
 815 bool schedule_aio_write_and_X(connection_struct *conn,
 816                               struct smb_request *req,
 817                               files_struct *fsp, char *data,
 818                               SMB_OFF_T startpos,
 819                               size_t numtowrite)
 820 {
 821         return False;
 822 }
 823
 824 void cancel_aio_by_fsp(files_struct *fsp)
 825 {
 826 }
 827
 828 int wait_for_aio_completion(files_struct *fsp)
 829 {
 830         return ENOSYS;
 831 }
 832 #endif