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 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 #ifndef SIGRTMIN
  28 #define SIGRTMIN        NSIG
  29 #endif
  30 #define RT_SIGNAL_AIO   (SIGRTMIN+3)
  31 #endif
  32
  33 #ifndef HAVE_STRUCT_SIGEVENT_SIGEV_VALUE_SIVAL_PTR
  34 #ifdef HAVE_STRUCT_SIGEVENT_SIGEV_VALUE_SIGVAL_PTR
  35 #define sival_int       sigval_int
  36 #define sival_ptr       sigval_ptr
  37 #endif
  38 #endif
  39
  40 /****************************************************************************
  41  The buffer we keep around whilst an aio request is in process.
  42 *****************************************************************************/
  43
  44 struct aio_extra {
  45         struct aio_extra *next, *prev;
  46         SMB_STRUCT_AIOCB acb;
  47         files_struct *fsp;
  48         bool read_req;
  49         uint16 mid;
  50         char *inbuf;
  51         char *outbuf;
  52 };
  53
  54 static struct aio_extra *aio_list_head;
  55
  56 /****************************************************************************
  57  Create the extended aio struct we must keep around for the lifetime
  58  of the aio_read call.
  59 *****************************************************************************/
  60
  61 static struct aio_extra *create_aio_ex_read(files_struct *fsp, size_t buflen,
  62                                             uint16 mid)
  63 {
  64         struct aio_extra *aio_ex = SMB_MALLOC_P(struct aio_extra);
  65
  66         if (!aio_ex) {
  67                 return NULL;
  68         }
  69         ZERO_STRUCTP(aio_ex);
  70         /* The output buffer stored in the aio_ex is the start of
  71            the smb return buffer. The buffer used in the acb
  72            is the start of the reply data portion of that buffer. */
  73         aio_ex->outbuf = SMB_MALLOC_ARRAY(char, buflen);
  74         if (!aio_ex->outbuf) {
  75                 SAFE_FREE(aio_ex);
  76                 return NULL;
  77         }
  78         DLIST_ADD(aio_list_head, aio_ex);
  79         aio_ex->fsp = fsp;
  80         aio_ex->read_req = True;
  81         aio_ex->mid = mid;
  82         return aio_ex;
  83 }
  84
  85 /****************************************************************************
  86  Create the extended aio struct we must keep around for the lifetime
  87  of the aio_write call.
  88 *****************************************************************************/
  89
  90 static struct aio_extra *create_aio_ex_write(files_struct *fsp,
  91                                              size_t inbuflen,
  92                                              size_t outbuflen,
  93                                              uint16 mid)
  94 {
  95         struct aio_extra *aio_ex = SMB_MALLOC_P(struct aio_extra);
  96
  97         if (!aio_ex) {
  98                 return NULL;
  99         }
 100         ZERO_STRUCTP(aio_ex);
 101
 102         /* We need space for an output reply of outbuflen bytes. */
 103         aio_ex->outbuf = SMB_MALLOC_ARRAY(char, outbuflen);
 104         if (!aio_ex->outbuf) {
 105                 SAFE_FREE(aio_ex);
 106                 return NULL;
 107         }
 108
 109         if (!(aio_ex->inbuf = SMB_MALLOC_ARRAY(char, inbuflen))) {
 110                 SAFE_FREE(aio_ex->outbuf);
 111                 SAFE_FREE(aio_ex);
 112                 return NULL;
 113         }
 114
 115         DLIST_ADD(aio_list_head, aio_ex);
 116         aio_ex->fsp = fsp;
 117         aio_ex->read_req = False;
 118         aio_ex->mid = mid;
 119         return aio_ex;
 120 }
 121
 122 /****************************************************************************
 123  Delete the extended aio struct.
 124 *****************************************************************************/
 125
 126 static void delete_aio_ex(struct aio_extra *aio_ex)
 127 {
 128         DLIST_REMOVE(aio_list_head, aio_ex);
 129         SAFE_FREE(aio_ex->inbuf);
 130         SAFE_FREE(aio_ex->outbuf);
 131         SAFE_FREE(aio_ex);
 132 }
 133
 134 /****************************************************************************
 135  Given the aiocb struct find the extended aio struct containing it.
 136 *****************************************************************************/
 137
 138 static struct aio_extra *find_aio_ex(uint16 mid)
 139 {
 140         struct aio_extra *p;
 141
 142         for( p = aio_list_head; p; p = p->next) {
 143                 if (mid == p->mid) {
 144                         return p;
 145                 }
 146         }
 147         return NULL;
 148 }
 149
 150 /****************************************************************************
 151  We can have these many aio buffers in flight.
 152 *****************************************************************************/
 153
 154 static int aio_pending_size;
 155 static sig_atomic_t signals_received;
 156 static int outstanding_aio_calls;
 157 static uint16 *aio_pending_array;
 158
 159 /****************************************************************************
 160  Signal handler when an aio request completes.
 161 *****************************************************************************/
 162
 163 void aio_request_done(uint16_t mid)
 164 {
 165         if (signals_received < aio_pending_size) {
 166                 aio_pending_array[signals_received] = mid;
 167                 signals_received++;
 168         }
 169         /* Else signal is lost. */
 170 }
 171
 172 static void signal_handler(int sig, siginfo_t *info, void *unused)
 173 {
 174         aio_request_done(info->si_value.sival_int);
 175         sys_select_signal(RT_SIGNAL_AIO);
 176 }
 177
 178 /****************************************************************************
 179  Is there a signal waiting ?
 180 *****************************************************************************/
 181
 182 bool aio_finished(void)
 183 {
 184         return (signals_received != 0);
 185 }
 186
 187 /****************************************************************************
 188  Initialize the signal handler for aio read/write.
 189 *****************************************************************************/
 190
 191 void initialize_async_io_handler(void)
 192 {
 193         struct sigaction act;
 194
 195         aio_pending_size = lp_maxmux();
 196         aio_pending_array = SMB_MALLOC_ARRAY(uint16, aio_pending_size);
 197         SMB_ASSERT(aio_pending_array != NULL);
 198
 199         ZERO_STRUCT(act);
 200         act.sa_sigaction = signal_handler;
 201         act.sa_flags = SA_SIGINFO;
 202         sigemptyset( &act.sa_mask );
 203         if (sigaction(RT_SIGNAL_AIO, &act, NULL) != 0) {
 204                 DEBUG(0,("Failed to setup RT_SIGNAL_AIO handler\n"));
 205         }
 206
 207         /* the signal can start off blocked due to a bug in bash */
 208         BlockSignals(False, RT_SIGNAL_AIO);
 209 }
 210
 211 /****************************************************************************
 212  Set up an aio request from a SMBreadX call.
 213 *****************************************************************************/
 214
 215 bool schedule_aio_read_and_X(connection_struct *conn,
 216                              struct smb_request *req,
 217                              files_struct *fsp, SMB_OFF_T startpos,
 218                              size_t smb_maxcnt)
 219 {
 220         struct aio_extra *aio_ex;
 221         SMB_STRUCT_AIOCB *a;
 222         size_t bufsize;
 223         size_t min_aio_read_size = lp_aio_read_size(SNUM(conn));
 224
 225         if (fsp->base_fsp != NULL) {
 226                 /* No AIO on streams yet */
 227                 DEBUG(10, ("AIO on streams not yet supported\n"));
 228                 return false;
 229         }
 230
 231         if ((!min_aio_read_size || (smb_maxcnt < min_aio_read_size))
 232             && !SMB_VFS_AIO_FORCE(fsp)) {
 233                 /* Too small a read for aio request. */
 234                 DEBUG(10,("schedule_aio_read_and_X: read size (%u) too small "
 235                           "for minimum aio_read of %u\n",
 236                           (unsigned int)smb_maxcnt,
 237                           (unsigned int)min_aio_read_size ));
 238                 return False;
 239         }
 240
 241         /* Only do this on non-chained and non-chaining reads not using the
 242          * write cache. */
 243         if (chain_size !=0 || (CVAL(req->inbuf,smb_vwv0) != 0xFF)
 244             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 245                 return False;
 246         }
 247
 248         if (outstanding_aio_calls >= aio_pending_size) {
 249                 DEBUG(10,("schedule_aio_read_and_X: Already have %d aio "
 250                           "activities outstanding.\n",
 251                           outstanding_aio_calls ));
 252                 return False;
 253         }
 254
 255         /* The following is safe from integer wrap as we've already checked
 256            smb_maxcnt is 128k or less. Wct is 12 for read replies */
 257
 258         bufsize = smb_size + 12 * 2 + smb_maxcnt;
 259
 260         if ((aio_ex = create_aio_ex_read(fsp, bufsize, req->mid)) == NULL) {
 261                 DEBUG(10,("schedule_aio_read_and_X: malloc fail.\n"));
 262                 return False;
 263         }
 264
 265         construct_reply_common((char *)req->inbuf, aio_ex->outbuf);
 266         srv_set_message(aio_ex->outbuf, 12, 0, True);
 267         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 268
 269         a = &aio_ex->acb;
 270
 271         /* Now set up the aio record for the read call. */
 272
 273         a->aio_fildes = fsp->fh->fd;
 274         a->aio_buf = smb_buf(aio_ex->outbuf);
 275         a->aio_nbytes = smb_maxcnt;
 276         a->aio_offset = startpos;
 277         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 278         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 279         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 280
 281         become_root();
 282         if (SMB_VFS_AIO_READ(fsp,a) == -1) {
 283                 DEBUG(0,("schedule_aio_read_and_X: aio_read failed. "
 284                          "Error %s\n", strerror(errno) ));
 285                 delete_aio_ex(aio_ex);
 286                 unbecome_root();
 287                 return False;
 288         }
 289         unbecome_root();
 290
 291         DEBUG(10,("schedule_aio_read_and_X: scheduled aio_read for file %s, "
 292                   "offset %.0f, len = %u (mid = %u)\n",
 293                   fsp->fsp_name, (double)startpos, (unsigned int)smb_maxcnt,
 294                   (unsigned int)aio_ex->mid ));
 295
 296         srv_defer_sign_response(aio_ex->mid);
 297         outstanding_aio_calls++;
 298         return True;
 299 }
 300
 301 /****************************************************************************
 302  Set up an aio request from a SMBwriteX call.
 303 *****************************************************************************/
 304
 305 bool schedule_aio_write_and_X(connection_struct *conn,
 306                               struct smb_request *req,
 307                               files_struct *fsp, char *data,
 308                               SMB_OFF_T startpos,
 309                               size_t numtowrite)
 310 {
 311         struct aio_extra *aio_ex;
 312         SMB_STRUCT_AIOCB *a;
 313         size_t inbufsize, outbufsize;
 314         bool write_through = BITSETW(req->inbuf+smb_vwv7,0);
 315         size_t min_aio_write_size = lp_aio_write_size(SNUM(conn));
 316
 317         if (fsp->base_fsp != NULL) {
 318                 /* No AIO on streams yet */
 319                 DEBUG(10, ("AIO on streams not yet supported\n"));
 320                 return false;
 321         }
 322
 323         if ((!min_aio_write_size || (numtowrite < min_aio_write_size))
 324             && !SMB_VFS_AIO_FORCE(fsp)) {
 325                 /* Too small a write for aio request. */
 326                 DEBUG(10,("schedule_aio_write_and_X: write size (%u) too "
 327                           "small for minimum aio_write of %u\n",
 328                           (unsigned int)numtowrite,
 329                           (unsigned int)min_aio_write_size ));
 330                 return False;
 331         }
 332
 333         /* Only do this on non-chained and non-chaining reads not using the
 334          * write cache. */
 335         if (chain_size !=0 || (CVAL(req->inbuf,smb_vwv0) != 0xFF)
 336             || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 337                 return False;
 338         }
 339
 340         if (outstanding_aio_calls >= aio_pending_size) {
 341                 DEBUG(3,("schedule_aio_write_and_X: Already have %d aio "
 342                          "activities outstanding.\n",
 343                           outstanding_aio_calls ));
 344                 DEBUG(10,("schedule_aio_write_and_X: failed to schedule "
 345                           "aio_write for file %s, offset %.0f, len = %u "
 346                           "(mid = %u)\n",
 347                           fsp->fsp_name, (double)startpos,
 348                           (unsigned int)numtowrite,
 349                           (unsigned int)req->mid ));
 350                 return False;
 351         }
 352
 353         inbufsize =  smb_len(req->inbuf) + 4;
 354         reply_outbuf(req, 6, 0);
 355         outbufsize = smb_len(req->outbuf) + 4;
 356         if (!(aio_ex = create_aio_ex_write(fsp, inbufsize, outbufsize,
 357                                            req->mid))) {
 358                 DEBUG(0,("schedule_aio_write_and_X: malloc fail.\n"));
 359                 return False;
 360         }
 361
 362         /* Copy the SMB header already setup in outbuf. */
 363         memcpy(aio_ex->inbuf, req->inbuf, inbufsize);
 364
 365         /* Copy the SMB header already setup in outbuf. */
 366         memcpy(aio_ex->outbuf, req->outbuf, outbufsize);
 367         TALLOC_FREE(req->outbuf);
 368         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 369
 370         a = &aio_ex->acb;
 371
 372         /* Now set up the aio record for the write call. */
 373
 374         a->aio_fildes = fsp->fh->fd;
 375         a->aio_buf = aio_ex->inbuf + (PTR_DIFF(data, req->inbuf));
 376         a->aio_nbytes = numtowrite;
 377         a->aio_offset = startpos;
 378         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 379         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 380         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 381
 382         become_root();
 383         if (SMB_VFS_AIO_WRITE(fsp,a) == -1) {
 384                 DEBUG(3,("schedule_aio_wrote_and_X: aio_write failed. "
 385                          "Error %s\n", strerror(errno) ));
 386                 delete_aio_ex(aio_ex);
 387                 unbecome_root();
 388                 return False;
 389         }
 390         unbecome_root();
 391
 392         release_level_2_oplocks_on_change(fsp);
 393
 394         if (!write_through && !lp_syncalways(SNUM(fsp->conn))
 395             && fsp->aio_write_behind) {
 396                 /* Lie to the client and immediately claim we finished the
 397                  * write. */
 398                 SSVAL(aio_ex->outbuf,smb_vwv2,numtowrite);
 399                 SSVAL(aio_ex->outbuf,smb_vwv4,(numtowrite>>16)&1);
 400                 show_msg(aio_ex->outbuf);
 401                 if (!srv_send_smb(smbd_server_fd(),aio_ex->outbuf,
 402                                 IS_CONN_ENCRYPTED(fsp->conn))) {
 403                         exit_server_cleanly("handle_aio_write: srv_send_smb "
 404                                             "failed.");
 405                 }
 406                 DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write "
 407                           "behind for file %s\n", fsp->fsp_name ));
 408         } else {
 409                 srv_defer_sign_response(aio_ex->mid);
 410         }
 411         outstanding_aio_calls++;
 412
 413         DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write for file "
 414                   "%s, offset %.0f, len = %u (mid = %u) "
 415                   "outstanding_aio_calls = %d\n",
 416                   fsp->fsp_name, (double)startpos, (unsigned int)numtowrite,
 417                   (unsigned int)aio_ex->mid, outstanding_aio_calls ));
 418
 419         return True;
 420 }
 421
 422
 423 /****************************************************************************
 424  Complete the read and return the data or error back to the client.
 425  Returns errno or zero if all ok.
 426 *****************************************************************************/
 427
 428 static int handle_aio_read_complete(struct aio_extra *aio_ex, int errcode)
 429 {
 430         int outsize;
 431         char *outbuf = aio_ex->outbuf;
 432         char *data = smb_buf(outbuf);
 433         ssize_t nread = SMB_VFS_AIO_RETURN(aio_ex->fsp,&aio_ex->acb);
 434
 435         if (nread < 0) {
 436                 /* We're relying here on the fact that if the fd is
 437                    closed then the aio will complete and aio_return
 438                    will return an error. Hopefully this is
 439                    true.... JRA. */
 440
 441                 DEBUG( 3,( "handle_aio_read_complete: file %s nread == %d. "
 442                            "Error = %s\n",
 443                            aio_ex->fsp->fsp_name, (int)nread, strerror(errcode) ));
 444
 445                 ERROR_NT(map_nt_error_from_unix(errcode));
 446                 outsize = srv_set_message(outbuf,0,0,true);
 447         } else {
 448                 outsize = srv_set_message(outbuf,12,nread,False);
 449                 SSVAL(outbuf,smb_vwv2,0xFFFF); /* Remaining - must be * -1. */
 450                 SSVAL(outbuf,smb_vwv5,nread);
 451                 SSVAL(outbuf,smb_vwv6,smb_offset(data,outbuf));
 452                 SSVAL(outbuf,smb_vwv7,((nread >> 16) & 1));
 453                 SSVAL(smb_buf(outbuf),-2,nread);
 454
 455                 aio_ex->fsp->fh->pos = aio_ex->acb.aio_offset + nread;
 456                 aio_ex->fsp->fh->position_information = aio_ex->fsp->fh->pos;
 457
 458                 DEBUG( 3, ( "handle_aio_read_complete file %s max=%d "
 459                             "nread=%d\n",
 460                             aio_ex->fsp->fsp_name,
 461                             (int)aio_ex->acb.aio_nbytes, (int)nread ) );
 462
 463         }
 464         smb_setlen(outbuf,outsize - 4);
 465         show_msg(outbuf);
 466         if (!srv_send_smb(smbd_server_fd(),outbuf,
 467                         IS_CONN_ENCRYPTED(aio_ex->fsp->conn))) {
 468                 exit_server_cleanly("handle_aio_read_complete: srv_send_smb "
 469                                     "failed.");
 470         }
 471
 472         DEBUG(10,("handle_aio_read_complete: scheduled aio_read completed "
 473                   "for file %s, offset %.0f, len = %u\n",
 474                   aio_ex->fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 475                   (unsigned int)nread ));
 476
 477         return errcode;
 478 }
 479
 480 /****************************************************************************
 481  Complete the write and return the data or error back to the client.
 482  Returns errno or zero if all ok.
 483 *****************************************************************************/
 484
 485 static int handle_aio_write_complete(struct aio_extra *aio_ex, int errcode)
 486 {
 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(errcode) ));
 499                         } else {
 500                                 DEBUG(0,("handle_aio_write_complete: "
 501                                          "aio_write_behind failed ! File %s "
 502                                          "is corrupt ! Wanted %u bytes but "
 503                                          "only wrote %d\n", fsp->fsp_name,
 504                                          (unsigned int)numtowrite,
 505                                          (int)nwritten ));
 506                                 errcode = EIO;
 507                         }
 508                 } else {
 509                         DEBUG(10,("handle_aio_write_complete: "
 510                                   "aio_write_behind completed for file %s\n",
 511                                   fsp->fsp_name ));
 512                 }
 513                 /* TODO: should no return 0 in case of an error !!! */
 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                 ERROR_NT(map_nt_error_from_unix(errcode));
 527                 srv_set_message(outbuf,0,0,true);
 528         } else {
 529                 bool write_through = BITSETW(aio_ex->inbuf+smb_vwv7,0);
 530                 NTSTATUS status;
 531
 532                 SSVAL(outbuf,smb_vwv2,nwritten);
 533                 SSVAL(outbuf,smb_vwv4,(nwritten>>16)&1);
 534                 if (nwritten < (ssize_t)numtowrite) {
 535                         SCVAL(outbuf,smb_rcls,ERRHRD);
 536                         SSVAL(outbuf,smb_err,ERRdiskfull);
 537                 }
 538
 539                 DEBUG(3,("handle_aio_write: fnum=%d num=%d wrote=%d\n",
 540                          fsp->fnum, (int)numtowrite, (int)nwritten));
 541                 status = sync_file(fsp->conn,fsp, write_through);
 542                 if (!NT_STATUS_IS_OK(status)) {
 543                         errcode = errno;
 544                         ERROR_BOTH(map_nt_error_from_unix(errcode),
 545                                    ERRHRD, ERRdiskfull);
 546                         srv_set_message(outbuf,0,0,true);
 547                         DEBUG(5,("handle_aio_write: sync_file for %s returned %s\n",
 548                                 fsp->fsp_name, nt_errstr(status) ));
 549                 }
 550
 551                 aio_ex->fsp->fh->pos = aio_ex->acb.aio_offset + nwritten;
 552         }
 553
 554         show_msg(outbuf);
 555         if (!srv_send_smb(smbd_server_fd(),outbuf,IS_CONN_ENCRYPTED(fsp->conn))) {
 556                 exit_server_cleanly("handle_aio_write: srv_send_smb failed.");
 557         }
 558
 559         DEBUG(10,("handle_aio_write_complete: scheduled aio_write completed "
 560                   "for file %s, offset %.0f, requested %u, written = %u\n",
 561                   fsp->fsp_name, (double)aio_ex->acb.aio_offset,
 562                   (unsigned int)numtowrite, (unsigned int)nwritten ));
 563
 564         return errcode;
 565 }
 566
 567 /****************************************************************************
 568  Handle any aio completion. Returns True if finished (and sets *perr if err
 569  was non-zero), False if not.
 570 *****************************************************************************/
 571
 572 static bool handle_aio_completed(struct aio_extra *aio_ex, int *perr)
 573 {
 574         int err;
 575
 576         if(!aio_ex) {
 577                 DEBUG(3, ("handle_aio_completed: Non-existing aio_ex passed\n"));
 578                 return false;
 579         }
 580
 581         /* Ensure the operation has really completed. */
 582         err = SMB_VFS_AIO_ERROR(aio_ex->fsp, &aio_ex->acb);
 583         if (err == EINPROGRESS) {
 584                 DEBUG(10,( "handle_aio_completed: operation mid %u still in "
 585                            "process for file %s\n",
 586                            aio_ex->mid, aio_ex->fsp->fsp_name ));
 587                 return False;
 588         } else if (err == ECANCELED) {
 589                 /* If error is ECANCELED then don't return anything to the
 590                  * client. */
 591                 DEBUG(10,( "handle_aio_completed: operation mid %u"
 592                         " canceled\n", aio_ex->mid));
 593                 srv_cancel_sign_response(aio_ex->mid, false);
 594                 return True;
 595         }
 596
 597
 598         if (aio_ex->read_req) {
 599                 err = handle_aio_read_complete(aio_ex, err);
 600         } else {
 601                 err = handle_aio_write_complete(aio_ex, err);
 602         }
 603
 604         if (err) {
 605                 *perr = err; /* Only save non-zero errors. */
 606         }
 607
 608         return True;
 609 }
 610
 611 /****************************************************************************
 612  Handle any aio completion inline.
 613  Returns non-zero errno if fail or zero if all ok.
 614 *****************************************************************************/
 615
 616 int process_aio_queue(void)
 617 {
 618         int i;
 619         int ret = 0;
 620
 621         BlockSignals(True, RT_SIGNAL_AIO);
 622
 623         DEBUG(10,("process_aio_queue: signals_received = %d\n",
 624                   (int)signals_received));
 625         DEBUG(10,("process_aio_queue: outstanding_aio_calls = %d\n",
 626                   outstanding_aio_calls));
 627
 628         if (!signals_received) {
 629                 BlockSignals(False, RT_SIGNAL_AIO);
 630                 return 0;
 631         }
 632
 633         /* Drain all the complete aio_reads. */
 634         for (i = 0; i < signals_received; i++) {
 635                 uint16 mid = aio_pending_array[i];
 636                 files_struct *fsp = NULL;
 637                 struct aio_extra *aio_ex = find_aio_ex(mid);
 638
 639                 if (!aio_ex) {
 640                         DEBUG(3,("process_aio_queue: Can't find record to "
 641                                  "match mid %u.\n", (unsigned int)mid));
 642                         srv_cancel_sign_response(mid, false);
 643                         continue;
 644                 }
 645
 646                 fsp = aio_ex->fsp;
 647                 if (fsp == NULL) {
 648                         /* file was closed whilst I/O was outstanding. Just
 649                          * ignore. */
 650                         DEBUG( 3,( "process_aio_queue: file closed whilst "
 651                                    "aio outstanding.\n"));
 652                         srv_cancel_sign_response(mid, false);
 653                         continue;
 654                 }
 655
 656                 if (!handle_aio_completed(aio_ex, &ret)) {
 657                         continue;
 658                 }
 659
 660                 delete_aio_ex(aio_ex);
 661         }
 662
 663         outstanding_aio_calls -= signals_received;
 664         signals_received = 0;
 665         BlockSignals(False, RT_SIGNAL_AIO);
 666         return ret;
 667 }
 668
 669 /****************************************************************************
 670  We're doing write behind and the client closed the file. Wait up to 30
 671  seconds (my arbitrary choice) for the aio to complete. Return 0 if all writes
 672  completed, errno to return if not.
 673 *****************************************************************************/
 674
 675 #define SMB_TIME_FOR_AIO_COMPLETE_WAIT 29
 676
 677 int wait_for_aio_completion(files_struct *fsp)
 678 {
 679         struct aio_extra *aio_ex;
 680         const SMB_STRUCT_AIOCB **aiocb_list;
 681         int aio_completion_count = 0;
 682         time_t start_time = time(NULL);
 683         int seconds_left;
 684
 685         for (seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT;
 686              seconds_left >= 0;) {
 687                 int err = 0;
 688                 int i;
 689                 struct timespec ts;
 690
 691                 aio_completion_count = 0;
 692                 for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 693                         if (aio_ex->fsp == fsp) {
 694                                 aio_completion_count++;
 695                         }
 696                 }
 697
 698                 if (!aio_completion_count) {
 699                         return 0;
 700                 }
 701
 702                 DEBUG(3,("wait_for_aio_completion: waiting for %d aio events "
 703                          "to complete.\n", aio_completion_count ));
 704
 705                 aiocb_list = SMB_MALLOC_ARRAY(const SMB_STRUCT_AIOCB *,
 706                                               aio_completion_count);
 707                 if (!aiocb_list) {
 708                         return ENOMEM;
 709                 }
 710
 711                 for( i = 0, aio_ex = aio_list_head;
 712                      aio_ex;
 713                      aio_ex = aio_ex->next) {
 714                         if (aio_ex->fsp == fsp) {
 715                                 aiocb_list[i++] = &aio_ex->acb;
 716                         }
 717                 }
 718
 719                 /* Now wait up to seconds_left for completion. */
 720                 ts.tv_sec = seconds_left;
 721                 ts.tv_nsec = 0;
 722
 723                 DEBUG(10,("wait_for_aio_completion: %d events, doing a wait "
 724                           "of %d seconds.\n",
 725                           aio_completion_count, seconds_left ));
 726
 727                 err = SMB_VFS_AIO_SUSPEND(fsp, aiocb_list,
 728                                           aio_completion_count, &ts);
 729
 730                 DEBUG(10,("wait_for_aio_completion: returned err = %d, "
 731                           "errno = %s\n", err, strerror(errno) ));
 732
 733                 if (err == -1 && errno == EAGAIN) {
 734                         DEBUG(0,("wait_for_aio_completion: aio_suspend timed "
 735                                  "out waiting for %d events after a wait of "
 736                                  "%d seconds\n", aio_completion_count,
 737                                  seconds_left));
 738                         /* Timeout. */
 739                         cancel_aio_by_fsp(fsp);
 740                         SAFE_FREE(aiocb_list);
 741                         return EIO;
 742                 }
 743
 744                 /* One or more events might have completed - process them if
 745                  * so. */
 746                 for( i = 0; i < aio_completion_count; i++) {
 747                         uint16 mid = aiocb_list[i]->aio_sigevent.sigev_value.sival_int;
 748
 749                         aio_ex = find_aio_ex(mid);
 750
 751                         if (!aio_ex) {
 752                                 DEBUG(0, ("wait_for_aio_completion: mid %u "
 753                                           "doesn't match an aio record\n",
 754                                           (unsigned int)mid ));
 755                                 continue;
 756                         }
 757
 758                         if (!handle_aio_completed(aio_ex, &err)) {
 759                                 continue;
 760                         }
 761                         delete_aio_ex(aio_ex);
 762                 }
 763
 764                 SAFE_FREE(aiocb_list);
 765                 seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT
 766                         - (time(NULL) - start_time);
 767         }
 768
 769         /* We timed out - we don't know why. Return ret if already an error,
 770          * else EIO. */
 771         DEBUG(10,("wait_for_aio_completion: aio_suspend timed out waiting "
 772                   "for %d events\n",
 773                   aio_completion_count));
 774
 775         return EIO;
 776 }
 777
 778 /****************************************************************************
 779  Cancel any outstanding aio requests. The client doesn't care about the reply.
 780 *****************************************************************************/
 781
 782 void cancel_aio_by_fsp(files_struct *fsp)
 783 {
 784         struct aio_extra *aio_ex;
 785
 786         for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 787                 if (aio_ex->fsp == fsp) {
 788                         /* Don't delete the aio_extra record as we may have
 789                            completed and don't yet know it. Just do the
 790                            aio_cancel call and return. */
 791                         SMB_VFS_AIO_CANCEL(fsp, &aio_ex->acb);
 792                         aio_ex->fsp = NULL; /* fsp will be closed when we
 793                                              * return. */
 794                 }
 795         }
 796 }
 797
 798 #else
 799 bool aio_finished(void)
 800 {
 801         return False;
 802 }
 803
 804 void initialize_async_io_handler(void)
 805 {
 806 }
 807
 808 int process_aio_queue(void)
 809 {
 810         return False;
 811 }
 812
 813 bool schedule_aio_read_and_X(connection_struct *conn,
 814                              struct smb_request *req,
 815                              files_struct *fsp, SMB_OFF_T startpos,
 816                              size_t smb_maxcnt)
 817 {
 818         return False;
 819 }
 820
 821 bool schedule_aio_write_and_X(connection_struct *conn,
 822                               struct smb_request *req,
 823                               files_struct *fsp, char *data,
 824                               SMB_OFF_T startpos,
 825                               size_t numtowrite)
 826 {
 827         return False;
 828 }
 829
 830 void cancel_aio_by_fsp(files_struct *fsp)
 831 {
 832 }
 833
 834 int wait_for_aio_completion(files_struct *fsp)
 835 {
 836         return ENOSYS;
 837 }
 838 #endif