release/src/router/samba3/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, 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, size_t outbuflen, uint16 mid)
  81 {
  82         struct aio_extra *aio_ex = SMB_MALLOC_P(struct aio_extra);
  83
  84         if (!aio_ex) {
  85                 return NULL;
  86         }
  87         ZERO_STRUCTP(aio_ex);
  88
  89         /* We need space for an output reply of outbuflen bytes. */
  90         aio_ex->outbuf = SMB_MALLOC_ARRAY(char, outbuflen);
  91         if (!aio_ex->outbuf) {
  92                 SAFE_FREE(aio_ex);
  93                 return NULL;
  94         }
  95         /* Steal the input buffer containing the write data from the main SMB call. */
  96         /* We must re-allocate a new one here. */
  97         if (NewInBuffer(&aio_ex->inbuf) == NULL) {
  98                 SAFE_FREE(aio_ex->outbuf);
  99                 SAFE_FREE(aio_ex);
 100                 return NULL;
 101         }
 102
 103         /* aio_ex->inbuf now contains the stolen old InBuf containing the data to write. */
 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 to do as we've removed ourselves from the in use list first. */
 120         free_InBuffer(aio_ex->inbuf);
 121
 122         SAFE_FREE(aio_ex->outbuf);
 123         SAFE_FREE(aio_ex);
 124 }
 125
 126 /****************************************************************************
 127  Given the aiocb struct find the extended aio struct containing it.
 128 *****************************************************************************/
 129
 130 static struct aio_extra *find_aio_ex(uint16 mid)
 131 {
 132         struct aio_extra *p;
 133
 134         for( p = aio_list_head; p; p = p->next) {
 135                 if (mid == p->mid) {
 136                         return p;
 137                 }
 138         }
 139         return NULL;
 140 }
 141
 142 /****************************************************************************
 143  We can have these many aio buffers in flight.
 144 *****************************************************************************/
 145
 146 #define AIO_PENDING_SIZE 10
 147 static sig_atomic_t signals_received;
 148 static int outstanding_aio_calls;
 149 static uint16 aio_pending_array[AIO_PENDING_SIZE];
 150
 151 /****************************************************************************
 152  Signal handler when an aio request completes.
 153 *****************************************************************************/
 154
 155 static void signal_handler(int sig, siginfo_t *info, void *unused)
 156 {
 157         if (signals_received < AIO_PENDING_SIZE - 1) {
 158                 aio_pending_array[signals_received] = info->si_value.sival_int;
 159                 signals_received++;
 160         } /* Else signal is lost. */
 161         sys_select_signal(RT_SIGNAL_AIO);
 162 }
 163
 164 /****************************************************************************
 165  Is there a signal waiting ?
 166 *****************************************************************************/
 167
 168 BOOL aio_finished(void)
 169 {
 170         return (signals_received != 0);
 171 }
 172
 173 /****************************************************************************
 174  Initialize the signal handler for aio read/write.
 175 *****************************************************************************/
 176
 177 void initialize_async_io_handler(void)
 178 {
 179         struct sigaction act;
 180
 181         ZERO_STRUCT(act);
 182         act.sa_sigaction = signal_handler;
 183         act.sa_flags = SA_SIGINFO;
 184         sigemptyset( &act.sa_mask );
 185         if (sigaction(RT_SIGNAL_AIO, &act, NULL) != 0) {
 186                 DEBUG(0,("Failed to setup RT_SIGNAL_AIO handler\n"));
 187         }
 188
 189         /* the signal can start off blocked due to a bug in bash */
 190         BlockSignals(False, RT_SIGNAL_AIO);
 191 }
 192
 193 /****************************************************************************
 194  Set up an aio request from a SMBreadX call.
 195 *****************************************************************************/
 196
 197 BOOL schedule_aio_read_and_X(connection_struct *conn,
 198                              char *inbuf, char *outbuf,
 199                              int length, int len_outbuf,
 200                              files_struct *fsp, SMB_OFF_T startpos,
 201                              size_t smb_maxcnt)
 202 {
 203         struct aio_extra *aio_ex;
 204         SMB_STRUCT_AIOCB *a;
 205         size_t bufsize;
 206         size_t min_aio_read_size = lp_aio_read_size(SNUM(conn));
 207
 208         if (!min_aio_read_size || (smb_maxcnt < min_aio_read_size)) {
 209                 /* Too small a read for aio request. */
 210                 DEBUG(10,("schedule_aio_read_and_X: read size (%u) too small "
 211                           "for minimum aio_read of %u\n",
 212                           (unsigned int)smb_maxcnt,
 213                           (unsigned int)min_aio_read_size ));
 214                 return False;
 215         }
 216
 217         /* Only do this on non-chained and non-chaining reads not using the write cache. */
 218         if (chain_size !=0 || (CVAL(inbuf,smb_vwv0) != 0xFF) || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 219                 return False;
 220         }
 221
 222         if (outstanding_aio_calls >= AIO_PENDING_SIZE) {
 223                 DEBUG(10,("schedule_aio_read_and_X: Already have %d aio activities outstanding.\n",
 224                           outstanding_aio_calls ));
 225                 return False;
 226         }
 227
 228         /* The following is safe from integer wrap as we've already
 229            checked smb_maxcnt is 128k or less. */
 230         bufsize = PTR_DIFF(smb_buf(outbuf),outbuf) + smb_maxcnt;
 231
 232         if ((aio_ex = create_aio_ex_read(fsp, bufsize, SVAL(inbuf,smb_mid))) == NULL) {
 233                 DEBUG(10,("schedule_aio_read_and_X: malloc fail.\n"));
 234                 return False;
 235         }
 236
 237         /* Copy the SMB header already setup in outbuf. */
 238         memcpy(aio_ex->outbuf, outbuf, smb_buf(outbuf) - outbuf);
 239         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 240
 241         a = &aio_ex->acb;
 242
 243         /* Now set up the aio record for the read call. */
 244
 245         a->aio_fildes = fsp->fh->fd;
 246         a->aio_buf = smb_buf(aio_ex->outbuf);
 247         a->aio_nbytes = smb_maxcnt;
 248         a->aio_offset = startpos;
 249         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 250         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 251         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 252
 253         if (SMB_VFS_AIO_READ(fsp,a) == -1) {
 254                 DEBUG(0,("schedule_aio_read_and_X: aio_read failed. Error %s\n",
 255                         strerror(errno) ));
 256                 delete_aio_ex(aio_ex);
 257                 return False;
 258         }
 259
 260         DEBUG(10,("schedule_aio_read_and_X: scheduled aio_read for file %s, offset %.0f, len = %u (mid = %u)\n",
 261                 fsp->fsp_name, (double)startpos, (unsigned int)smb_maxcnt, (unsigned int)aio_ex->mid ));
 262
 263         srv_defer_sign_response(aio_ex->mid);
 264         outstanding_aio_calls++;
 265         return True;
 266 }
 267
 268 /****************************************************************************
 269  Set up an aio request from a SMBwriteX call.
 270 *****************************************************************************/
 271
 272 BOOL schedule_aio_write_and_X(connection_struct *conn,
 273                                 char *inbuf, char *outbuf,
 274                                 int length, int len_outbuf,
 275                                 files_struct *fsp, char *data,
 276                                 SMB_OFF_T startpos,
 277                                 size_t numtowrite)
 278 {
 279         struct aio_extra *aio_ex;
 280         SMB_STRUCT_AIOCB *a;
 281         size_t outbufsize;
 282         BOOL write_through = BITSETW(inbuf+smb_vwv7,0);
 283         size_t min_aio_write_size = lp_aio_write_size(SNUM(conn));
 284
 285         if (!min_aio_write_size || (numtowrite < min_aio_write_size)) {
 286                 /* Too small a write for aio request. */
 287                 DEBUG(10,("schedule_aio_write_and_X: write size (%u) too small "
 288                           "for minimum aio_write of %u\n",
 289                           (unsigned int)numtowrite,
 290                           (unsigned int)min_aio_write_size ));
 291                 return False;
 292         }
 293
 294         /* Only do this on non-chained and non-chaining reads not using the write cache. */
 295         if (chain_size !=0 || (CVAL(inbuf,smb_vwv0) != 0xFF) || (lp_write_cache_size(SNUM(conn)) != 0) ) {
 296                 return False;
 297         }
 298
 299         if (outstanding_aio_calls >= AIO_PENDING_SIZE) {
 300                 DEBUG(3,("schedule_aio_write_and_X: Already have %d aio activities outstanding.\n",
 301                           outstanding_aio_calls ));
 302                 DEBUG(10,("schedule_aio_write_and_X: failed to schedule aio_write for file %s, offset %.0f, len = %u (mid = %u)\n",
 303                         fsp->fsp_name, (double)startpos, (unsigned int)numtowrite, (unsigned int)SVAL(inbuf,smb_mid) ));
 304                 return False;
 305         }
 306
 307         outbufsize = smb_len(outbuf) + 4;
 308         if ((aio_ex = create_aio_ex_write(fsp, outbufsize, SVAL(inbuf,smb_mid))) == NULL) {
 309                 DEBUG(0,("schedule_aio_write_and_X: malloc fail.\n"));
 310                 return False;
 311         }
 312
 313         /* Paranioa.... */
 314         SMB_ASSERT(aio_ex->inbuf == inbuf);
 315
 316         /* Copy the SMB header already setup in outbuf. */
 317         memcpy(aio_ex->outbuf, outbuf, outbufsize);
 318         SCVAL(aio_ex->outbuf,smb_vwv0,0xFF); /* Never a chained reply. */
 319
 320         a = &aio_ex->acb;
 321
 322         /* Now set up the aio record for the write call. */
 323
 324         a->aio_fildes = fsp->fh->fd;
 325         a->aio_buf = data; /* As we've stolen inbuf this points within inbuf. */
 326         a->aio_nbytes = numtowrite;
 327         a->aio_offset = startpos;
 328         a->aio_sigevent.sigev_notify = SIGEV_SIGNAL;
 329         a->aio_sigevent.sigev_signo  = RT_SIGNAL_AIO;
 330         a->aio_sigevent.sigev_value.sival_int = aio_ex->mid;
 331
 332         if (SMB_VFS_AIO_WRITE(fsp,a) == -1) {
 333                 DEBUG(3,("schedule_aio_wrote_and_X: aio_write failed. Error %s\n",
 334                         strerror(errno) ));
 335                 /* Replace global InBuf as we're going to do a normal write. */
 336                 set_InBuffer(aio_ex->inbuf);
 337                 aio_ex->inbuf = NULL;
 338                 delete_aio_ex(aio_ex);
 339                 return False;
 340         }
 341
 342         if (!write_through && !lp_syncalways(SNUM(fsp->conn)) && fsp->aio_write_behind) {
 343                 /* Lie to the client and immediately claim we finished the write. */
 344                 SSVAL(aio_ex->outbuf,smb_vwv2,numtowrite);
 345                 SSVAL(aio_ex->outbuf,smb_vwv4,(numtowrite>>16)&1);
 346                 show_msg(aio_ex->outbuf);
 347                 if (!send_smb(smbd_server_fd(),aio_ex->outbuf)) {
 348                         exit_server("handle_aio_write: send_smb failed.");
 349                 }
 350                 DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write behind for file %s\n",
 351                         fsp->fsp_name ));
 352         } else {
 353                 srv_defer_sign_response(aio_ex->mid);
 354         }
 355         outstanding_aio_calls++;
 356
 357         DEBUG(10,("schedule_aio_write_and_X: scheduled aio_write for file %s, \
 358 offset %.0f, len = %u (mid = %u) outstanding_aio_calls = %d\n",
 359                 fsp->fsp_name, (double)startpos, (unsigned int)numtowrite, (unsigned int)aio_ex->mid, outstanding_aio_calls ));
 360
 361         return True;
 362 }
 363
 364
 365 /****************************************************************************
 366  Complete the read and return the data or error back to the client.
 367  Returns errno or zero if all ok.
 368 *****************************************************************************/
 369
 370 static int handle_aio_read_complete(struct aio_extra *aio_ex)
 371 {
 372         int ret = 0;
 373         int outsize;
 374         char *outbuf = aio_ex->outbuf;
 375         char *data = smb_buf(outbuf);
 376         ssize_t nread = SMB_VFS_AIO_RETURN(aio_ex->fsp,&aio_ex->acb);
 377
 378         if (nread < 0) {
 379                 /* We're relying here on the fact that if the fd is
 380                    closed then the aio will complete and aio_return
 381                    will return an error. Hopefully this is
 382                    true.... JRA. */
 383
 384                 /* If errno is ECANCELED then don't return anything to the client. */
 385                 if (errno == ECANCELED) {
 386                         srv_cancel_sign_response(aio_ex->mid);
 387                         return 0;
 388                 }
 389
 390                 DEBUG( 3,( "handle_aio_read_complete: file %s nread == -1. Error = %s\n",
 391                         aio_ex->fsp->fsp_name, strerror(errno) ));
 392
 393                 outsize = (UNIXERROR(ERRDOS,ERRnoaccess));
 394                 ret = errno;
 395         } else {
 396                 outsize = set_message(outbuf,12,nread,False);
 397                 SSVAL(outbuf,smb_vwv2,0xFFFF); /* Remaining - must be * -1. */
 398                 SSVAL(outbuf,smb_vwv5,nread);
 399                 SSVAL(outbuf,smb_vwv6,smb_offset(data,outbuf));
 400                 SSVAL(outbuf,smb_vwv7,((nread >> 16) & 1));
 401                 SSVAL(smb_buf(outbuf),-2,nread);
 402
 403                 DEBUG( 3, ( "handle_aio_read_complete file %s max=%d nread=%d\n",
 404                         aio_ex->fsp->fsp_name,
 405                         aio_ex->acb.aio_nbytes, (int)nread ) );
 406
 407         }
 408         smb_setlen(outbuf,outsize - 4);
 409         show_msg(outbuf);
 410         if (!send_smb(smbd_server_fd(),outbuf)) {
 411                 exit_server("handle_aio_read_complete: send_smb failed.");
 412         }
 413
 414         DEBUG(10,("handle_aio_read_complete: scheduled aio_read completed for file %s, offset %.0f, len = %u\n",
 415                 aio_ex->fsp->fsp_name, (double)aio_ex->acb.aio_offset, (unsigned int)nread ));
 416
 417         return ret;
 418 }
 419
 420 /****************************************************************************
 421  Complete the write and return the data or error back to the client.
 422  Returns errno or zero if all ok.
 423 *****************************************************************************/
 424
 425 static int handle_aio_write_complete(struct aio_extra *aio_ex)
 426 {
 427         int ret = 0;
 428         files_struct *fsp = aio_ex->fsp;
 429         char *outbuf = aio_ex->outbuf;
 430         ssize_t numtowrite = aio_ex->acb.aio_nbytes;
 431         ssize_t nwritten = SMB_VFS_AIO_RETURN(fsp,&aio_ex->acb);
 432
 433         if (fsp->aio_write_behind) {
 434                 if (nwritten != numtowrite) {
 435                         if (nwritten == -1) {
 436                                 DEBUG(5,("handle_aio_write_complete: aio_write_behind failed ! File %s is corrupt ! Error %s\n",
 437                                         fsp->fsp_name, strerror(errno) ));
 438                                 ret = errno;
 439                         } else {
 440                                 DEBUG(0,("handle_aio_write_complete: aio_write_behind failed ! File %s is corrupt ! \
 441 Wanted %u bytes but only wrote %d\n", fsp->fsp_name, (unsigned int)numtowrite, (int)nwritten ));
 442                                 ret = EIO;
 443                         }
 444                 } else {
 445                         DEBUG(10,("handle_aio_write_complete: aio_write_behind completed for file %s\n",
 446                                 fsp->fsp_name ));
 447                 }
 448                 return 0;
 449         }
 450
 451         /* We don't need outsize or set_message here as we've already set the
 452            fixed size length when we set up the aio call. */
 453
 454         if(nwritten == -1) {
 455                 DEBUG( 3,( "handle_aio_write: file %s wanted %u bytes. nwritten == %d. Error = %s\n",
 456                         fsp->fsp_name, (unsigned int)numtowrite,
 457                         (int)nwritten, strerror(errno) ));
 458
 459                 /* If errno is ECANCELED then don't return anything to the client. */
 460                 if (errno == ECANCELED) {
 461                         srv_cancel_sign_response(aio_ex->mid);
 462                         return 0;
 463                 }
 464
 465                 UNIXERROR(ERRHRD,ERRdiskfull);
 466                 ret = errno;
 467         } else {
 468                 BOOL write_through = BITSETW(aio_ex->inbuf+smb_vwv7,0);
 469
 470                 SSVAL(outbuf,smb_vwv2,nwritten);
 471                 SSVAL(outbuf,smb_vwv4,(nwritten>>16)&1);
 472                 if (nwritten < (ssize_t)numtowrite) {
 473                         SCVAL(outbuf,smb_rcls,ERRHRD);
 474                         SSVAL(outbuf,smb_err,ERRdiskfull);
 475                 }
 476
 477                 DEBUG(3,("handle_aio_write: fnum=%d num=%d wrote=%d\n", fsp->fnum, (int)numtowrite, (int)nwritten));
 478                 sync_file(fsp->conn,fsp, write_through);
 479         }
 480
 481         show_msg(outbuf);
 482         if (!send_smb(smbd_server_fd(),outbuf)) {
 483                 exit_server("handle_aio_write: send_smb failed.");
 484         }
 485
 486         DEBUG(10,("handle_aio_write_complete: scheduled aio_write completed for file %s, offset %.0f, requested %u, written = %u\n",
 487                 fsp->fsp_name, (double)aio_ex->acb.aio_offset, (unsigned int)numtowrite, (unsigned int)nwritten ));
 488
 489         return ret;
 490 }
 491
 492 /****************************************************************************
 493  Handle any aio completion. Returns True if finished (and sets *perr if err was non-zero),
 494  False if not.
 495 *****************************************************************************/
 496
 497 static BOOL handle_aio_completed(struct aio_extra *aio_ex, int *perr)
 498 {
 499         int err;
 500
 501         /* Ensure the operation has really completed. */
 502         if (SMB_VFS_AIO_ERROR(aio_ex->fsp, &aio_ex->acb) == EINPROGRESS) {
 503                 DEBUG(10,( "handle_aio_completed: operation mid %u still in process for file %s\n",
 504                         aio_ex->mid, aio_ex->fsp->fsp_name ));
 505                 return False;
 506         }
 507
 508         if (aio_ex->read_req) {
 509                 err = handle_aio_read_complete(aio_ex);
 510         } else {
 511                 err = handle_aio_write_complete(aio_ex);
 512         }
 513
 514         if (err) {
 515                 *perr = err; /* Only save non-zero errors. */
 516         }
 517
 518         return True;
 519 }
 520
 521 /****************************************************************************
 522  Handle any aio completion inline.
 523  Returns non-zero errno if fail or zero if all ok.
 524 *****************************************************************************/
 525
 526 int process_aio_queue(void)
 527 {
 528         int i;
 529         int ret = 0;
 530
 531         BlockSignals(True, RT_SIGNAL_AIO);
 532
 533         DEBUG(10,("process_aio_queue: signals_received = %d\n", (int)signals_received));
 534         DEBUG(10,("process_aio_queue: outstanding_aio_calls = %d\n", outstanding_aio_calls));
 535
 536         if (!signals_received) {
 537                 BlockSignals(False, RT_SIGNAL_AIO);
 538                 return 0;
 539         }
 540
 541         /* Drain all the complete aio_reads. */
 542         for (i = 0; i < signals_received; i++) {
 543                 uint16 mid = aio_pending_array[i];
 544                 files_struct *fsp = NULL;
 545                 struct aio_extra *aio_ex = find_aio_ex(mid);
 546
 547                 if (!aio_ex) {
 548                         DEBUG(3,("process_aio_queue: Can't find record to match mid %u.\n",
 549                                 (unsigned int)mid));
 550                         srv_cancel_sign_response(mid);
 551                         continue;
 552                 }
 553
 554                 fsp = aio_ex->fsp;
 555                 if (fsp == NULL) {
 556                         /* file was closed whilst I/O was outstanding. Just ignore. */
 557                         DEBUG( 3,( "process_aio_queue: file closed whilst aio outstanding.\n"));
 558                         srv_cancel_sign_response(mid);
 559                         continue;
 560                 }
 561
 562                 if (!handle_aio_completed(aio_ex, &ret)) {
 563                         continue;
 564                 }
 565
 566                 delete_aio_ex(aio_ex);
 567         }
 568
 569         outstanding_aio_calls -= signals_received;
 570         signals_received = 0;
 571         BlockSignals(False, RT_SIGNAL_AIO);
 572         return ret;
 573 }
 574
 575 /****************************************************************************
 576  We're doing write behind and the client closed the file. Wait up to 30 seconds
 577  (my arbitrary choice) for the aio to complete. Return 0 if all writes completed,
 578  errno to return if not.
 579 *****************************************************************************/
 580
 581 #define SMB_TIME_FOR_AIO_COMPLETE_WAIT 29
 582
 583 BOOL wait_for_aio_completion(files_struct *fsp)
 584 {
 585         struct aio_extra *aio_ex;
 586         const SMB_STRUCT_AIOCB **aiocb_list;
 587         int aio_completion_count = 0;
 588         time_t start_time = time(NULL);
 589         int seconds_left;
 590         int ret = 0;
 591
 592         for (seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT; seconds_left >= 0;) {
 593                 int err = 0;
 594                 int i;
 595                 struct timespec ts;
 596
 597                 aio_completion_count = 0;
 598                 for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 599                         if (aio_ex->fsp == fsp) {
 600                                 aio_completion_count++;
 601                         }
 602                 }
 603
 604                 if (!aio_completion_count) {
 605                         return ret;
 606                 }
 607
 608                 DEBUG(3,("wait_for_aio_completion: waiting for %d aio events to complete.\n",
 609                         aio_completion_count ));
 610
 611                 aiocb_list = SMB_MALLOC_ARRAY(const SMB_STRUCT_AIOCB *, aio_completion_count);
 612                 if (!aiocb_list) {
 613                         return False;
 614                 }
 615
 616                 for( i = 0, aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 617                         if (aio_ex->fsp == fsp) {
 618                                 aiocb_list[i++] = &aio_ex->acb;
 619                         }
 620                 }
 621
 622                 /* Now wait up to seconds_left for completion. */
 623                 ts.tv_sec = seconds_left;
 624                 ts.tv_nsec = 0;
 625
 626                 DEBUG(10,("wait_for_aio_completion: %d events, doing a wait of %d seconds.\n",
 627                         aio_completion_count, seconds_left ));
 628
 629                 err = SMB_VFS_AIO_SUSPEND(fsp, aiocb_list, aio_completion_count, &ts);
 630
 631                 DEBUG(10,("wait_for_aio_completion: returned err = %d, errno = %s\n",
 632                         err, strerror(errno) ));
 633
 634                 if (err == -1 && errno == EAGAIN) {
 635                         DEBUG(0,("wait_for_aio_completion: aio_suspend timed out waiting for %d events after a wait of %d seconds\n",
 636                                         aio_completion_count, seconds_left));
 637                         /* Timeout. */
 638                         cancel_aio_by_fsp(fsp);
 639                         SAFE_FREE(aiocb_list);
 640                         return ret ? ret : EIO;
 641                 }
 642
 643                 /* One or more events might have completed - process them if so. */
 644                 for( i = 0; i < aio_completion_count; i++) {
 645                         uint16 mid = aiocb_list[i]->aio_sigevent.sigev_value.sival_int;
 646
 647                         aio_ex = find_aio_ex(mid);
 648
 649                         if (!aio_ex) {
 650                                 DEBUG(0, ("wait_for_aio_completion: mid %u doesn't match an aio record\n",
 651                                         (unsigned int)mid ));
 652                                 continue;
 653                         }
 654
 655                         if (!handle_aio_completed(aio_ex, &err)) {
 656                                 continue;
 657                         }
 658                         delete_aio_ex(aio_ex);
 659                 }
 660
 661                 SAFE_FREE(aiocb_list);
 662                 seconds_left = SMB_TIME_FOR_AIO_COMPLETE_WAIT - (time(NULL) - start_time);
 663         }
 664
 665         /* We timed out - we don't know why. Return ret if already an error, else EIO. */
 666         DEBUG(10,("wait_for_aio_completion: aio_suspend timed out waiting for %d events\n",
 667                         aio_completion_count));
 668
 669         return ret ? ret : EIO;
 670 }
 671
 672 /****************************************************************************
 673  Cancel any outstanding aio requests. The client doesn't care about the reply.
 674 *****************************************************************************/
 675
 676 void cancel_aio_by_fsp(files_struct *fsp)
 677 {
 678         struct aio_extra *aio_ex;
 679
 680         for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 681                 if (aio_ex->fsp == fsp) {
 682                         /* Don't delete the aio_extra record as we may have completed
 683                            and don't yet know it. Just do the aio_cancel call and return. */
 684                         SMB_VFS_AIO_CANCEL(fsp,fsp->fh->fd, &aio_ex->acb);
 685                         aio_ex->fsp = NULL; /* fsp will be closed when we return. */
 686                 }
 687         }
 688 }
 689
 690 /****************************************************************************
 691  Check if a buffer was stolen for aio use.
 692 *****************************************************************************/
 693
 694 BOOL aio_inbuffer_in_use(char *inbuf)
 695 {
 696         struct aio_extra *aio_ex;
 697
 698         for( aio_ex = aio_list_head; aio_ex; aio_ex = aio_ex->next) {
 699                 if (aio_ex->inbuf == inbuf) {
 700                         return True;
 701                 }
 702         }
 703         return False;
 704 }
 705 #else
 706 BOOL aio_finished(void)
 707 {
 708         return False;
 709 }
 710
 711 void initialize_async_io_handler(void)
 712 {
 713 }
 714
 715 int process_aio_queue(void)
 716 {
 717         return False;
 718 }
 719
 720 BOOL schedule_aio_read_and_X(connection_struct *conn,
 721                              char *inbuf, char *outbuf,
 722                              int length, int len_outbuf,
 723                              files_struct *fsp, SMB_OFF_T startpos,
 724                              size_t smb_maxcnt)
 725 {
 726         return False;
 727 }
 728
 729 BOOL schedule_aio_write_and_X(connection_struct *conn,
 730                                 char *inbuf, char *outbuf,
 731                                 int length, int len_outbuf,
 732                                 files_struct *fsp, char *data,
 733                                 SMB_OFF_T startpos,
 734                                 size_t numtowrite)
 735 {
 736         return False;
 737 }
 738
 739 void cancel_aio_by_fsp(files_struct *fsp)
 740 {
 741 }
 742
 743 BOOL wait_for_aio_completion(files_struct *fsp)
 744 {
 745         return True;
 746 }
 747
 748 BOOL aio_inbuffer_in_use(char *ptr)
 749 {
 750         return False;
 751 }
 752 #endif