server/async.c

   1 /*
   2  * Server-side async I/O support
   3  *
   4  * Copyright (C) 2007 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include <assert.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <stdarg.h>
  25
  26 #include "ntstatus.h"
  27 #define WIN32_NO_STATUS
  28 #include "windef.h"
  29 #include "winternl.h"
  30
  31 #include "object.h"
  32 #include "file.h"
  33 #include "request.h"
  34 #include "process.h"
  35 #include "handle.h"
  36
  37 struct async
  38 {
  39     struct object        obj;             /* object header */
  40     struct thread       *thread;          /* owning thread */
  41     struct list          queue_entry;     /* entry in async queue list */
  42     struct list          process_entry;   /* entry in process list */
  43     struct async_queue  *queue;           /* queue containing this async */
  44     struct fd           *fd;              /* fd associated with an unqueued async */
  45     unsigned int         status;          /* current status */
  46     struct timeout_user *timeout;
  47     unsigned int         timeout_status;  /* status to report upon timeout */
  48     int                  signaled;
  49     struct event        *event;
  50     async_data_t         data;            /* data for async I/O call */
  51     struct iosb         *iosb;            /* I/O status block */
  52     obj_handle_t         wait_handle;     /* pre-allocated wait handle */
  53     int                  direct_result;   /* a flag if we're passing result directly from request instead of APC  */
  54 };
  55
  56 static void async_dump( struct object *obj, int verbose );
  57 static int async_signaled( struct object *obj, struct wait_queue_entry *entry );
  58 static void async_satisfied( struct object * obj, struct wait_queue_entry *entry );
  59 static void async_destroy( struct object *obj );
  60
  61 static const struct object_ops async_ops =
  62 {
  63     sizeof(struct async),      /* size */
  64     async_dump,                /* dump */
  65     no_get_type,               /* get_type */
  66     add_queue,                 /* add_queue */
  67     remove_queue,              /* remove_queue */
  68     async_signaled,            /* signaled */
  69     async_satisfied,           /* satisfied */
  70     no_signal,                 /* signal */
  71     no_get_fd,                 /* get_fd */
  72     no_map_access,             /* map_access */
  73     default_get_sd,            /* get_sd */
  74     default_set_sd,            /* set_sd */
  75     no_lookup_name,            /* lookup_name */
  76     no_link_name,              /* link_name */
  77     NULL,                      /* unlink_name */
  78     no_open_file,              /* open_file */
  79     no_close_handle,           /* close_handle */
  80     async_destroy              /* destroy */
  81 };
  82
  83
  84 struct async_queue
  85 {
  86     struct object        obj;             /* object header */
  87     struct fd           *fd;              /* file descriptor owning this queue */
  88     struct completion   *completion;      /* completion associated with a recently closed file descriptor */
  89     apc_param_t          comp_key;        /* completion key associated with a recently closed file descriptor */
  90     struct list          queue;           /* queue of async objects */
  91 };
  92
  93 static void async_queue_dump( struct object *obj, int verbose );
  94 static void async_queue_destroy( struct object *obj );
  95
  96 static const struct object_ops async_queue_ops =
  97 {
  98     sizeof(struct async_queue),      /* size */
  99     async_queue_dump,                /* dump */
 100     no_get_type,                     /* get_type */
 101     no_add_queue,                    /* add_queue */
 102     NULL,                            /* remove_queue */
 103     NULL,                            /* signaled */
 104     NULL,                            /* satisfied */
 105     no_signal,                       /* signal */
 106     no_get_fd,                       /* get_fd */
 107     no_map_access,                   /* map_access */
 108     default_get_sd,                  /* get_sd */
 109     default_set_sd,                  /* set_sd */
 110     no_lookup_name,                  /* lookup_name */
 111     no_link_name,                    /* link_name */
 112     NULL,                            /* unlink_name */
 113     no_open_file,                    /* open_file */
 114     no_close_handle,                 /* close_handle */
 115     async_queue_destroy              /* destroy */
 116 };
 117
 118
 119 static inline void async_reselect( struct async *async )
 120 {
 121     if (async->queue && async->queue->fd) fd_reselect_async( async->queue->fd, async->queue );
 122 }
 123
 124 static void async_dump( struct object *obj, int verbose )
 125 {
 126     struct async *async = (struct async *)obj;
 127     assert( obj->ops == &async_ops );
 128     fprintf( stderr, "Async thread=%p\n", async->thread );
 129 }
 130
 131 static int async_signaled( struct object *obj, struct wait_queue_entry *entry )
 132 {
 133     struct async *async = (struct async *)obj;
 134     assert( obj->ops == &async_ops );
 135     return async->signaled;
 136 }
 137
 138 static void async_satisfied( struct object *obj, struct wait_queue_entry *entry )
 139 {
 140     struct async *async = (struct async *)obj;
 141     assert( obj->ops == &async_ops );
 142
 143     if (async->direct_result)
 144     {
 145         async_set_result( &async->obj, async->iosb->status, async->iosb->result );
 146         async->direct_result = 0;
 147     }
 148
 149     /* close wait handle here to avoid extra server round trip */
 150     if (async->wait_handle)
 151     {
 152         close_handle( async->thread->process, async->wait_handle );
 153         async->wait_handle = 0;
 154     }
 155 }
 156
 157 static void async_destroy( struct object *obj )
 158 {
 159     struct async *async = (struct async *)obj;
 160     assert( obj->ops == &async_ops );
 161
 162     list_remove( &async->process_entry );
 163
 164     if (async->queue)
 165     {
 166         list_remove( &async->queue_entry );
 167         async_reselect( async );
 168         release_object( async->queue );
 169     }
 170
 171     if (async->fd) release_object( async->fd );
 172     if (async->timeout) remove_timeout_user( async->timeout );
 173     if (async->event) release_object( async->event );
 174     if (async->iosb) release_object( async->iosb );
 175     release_object( async->thread );
 176 }
 177
 178 static void async_queue_dump( struct object *obj, int verbose )
 179 {
 180     struct async_queue *async_queue = (struct async_queue *)obj;
 181     assert( obj->ops == &async_queue_ops );
 182     fprintf( stderr, "Async queue fd=%p\n", async_queue->fd );
 183 }
 184
 185 static void async_queue_destroy( struct object *obj )
 186 {
 187     struct async_queue *async_queue = (struct async_queue *)obj;
 188     assert( obj->ops == &async_queue_ops );
 189     if (async_queue->completion) release_object( async_queue->completion );
 190 }
 191
 192 /* notifies client thread of new status of its async request */
 193 void async_terminate( struct async *async, unsigned int status )
 194 {
 195     assert( status != STATUS_PENDING );
 196
 197     if (async->status != STATUS_PENDING)
 198     {
 199         /* already terminated, just update status */
 200         async->status = status;
 201         return;
 202     }
 203
 204     async->status = status;
 205     if (async->iosb && async->iosb->status == STATUS_PENDING) async->iosb->status = status;
 206
 207     if (!async->direct_result)
 208     {
 209         if (async->data.user)
 210         {
 211             apc_call_t data;
 212
 213             memset( &data, 0, sizeof(data) );
 214             data.type            = APC_ASYNC_IO;
 215             data.async_io.user   = async->data.user;
 216             data.async_io.sb     = async->data.iosb;
 217             data.async_io.status = status;
 218             thread_queue_apc( async->thread, &async->obj, &data );
 219         }
 220         else async_set_result( &async->obj, STATUS_SUCCESS, 0 );
 221     }
 222
 223     async_reselect( async );
 224     if (async->queue) release_object( async );  /* so that it gets destroyed when the async is done */
 225 }
 226
 227 /* callback for timeout on an async request */
 228 static void async_timeout( void *private )
 229 {
 230     struct async *async = private;
 231
 232     async->timeout = NULL;
 233     async_terminate( async, async->timeout_status );
 234 }
 235
 236 /* create a new async queue for a given fd */
 237 struct async_queue *create_async_queue( struct fd *fd )
 238 {
 239     struct async_queue *queue = alloc_object( &async_queue_ops );
 240
 241     if (queue)
 242     {
 243         queue->fd = fd;
 244         queue->completion = NULL;
 245         list_init( &queue->queue );
 246     }
 247     return queue;
 248 }
 249
 250 /* free an async queue, cancelling all async operations */
 251 void free_async_queue( struct async_queue *queue )
 252 {
 253     if (!queue) return;
 254     if (queue->fd) queue->completion = fd_get_completion( queue->fd, &queue->comp_key );
 255     queue->fd = NULL;
 256     async_wake_up( queue, STATUS_HANDLES_CLOSED );
 257     release_object( queue );
 258 }
 259
 260 void queue_async( struct async_queue *queue, struct async *async )
 261 {
 262     release_object( async->fd );
 263     async->fd = NULL;
 264
 265     async->queue = (struct async_queue *)grab_object( queue );
 266     grab_object( async );
 267     list_add_tail( &queue->queue, &async->queue_entry );
 268
 269     if (queue->fd) set_fd_signaled( queue->fd, 0 );
 270 }
 271
 272 /* create an async on a given queue of a fd */
 273 struct async *create_async( struct fd *fd, struct thread *thread, const async_data_t *data, struct iosb *iosb )
 274 {
 275     struct event *event = NULL;
 276     struct async *async;
 277
 278     if (data->event && !(event = get_event_obj( thread->process, data->event, EVENT_MODIFY_STATE )))
 279         return NULL;
 280
 281     if (!(async = alloc_object( &async_ops )))
 282     {
 283         if (event) release_object( event );
 284         return NULL;
 285     }
 286
 287     async->thread        = (struct thread *)grab_object( thread );
 288     async->event         = event;
 289     async->status        = STATUS_PENDING;
 290     async->data          = *data;
 291     async->timeout       = NULL;
 292     async->queue         = NULL;
 293     async->fd            = (struct fd *)grab_object( fd );
 294     async->signaled      = 0;
 295     async->wait_handle   = 0;
 296     async->direct_result = 0;
 297
 298     if (iosb) async->iosb = (struct iosb *)grab_object( iosb );
 299     else async->iosb = NULL;
 300
 301     list_add_head( &thread->process->asyncs, &async->process_entry );
 302     if (event) reset_event( event );
 303
 304     return async;
 305 }
 306
 307 /* create an async associated with iosb for async-based requests
 308  * returned async must be passed to async_handoff */
 309 struct async *create_request_async( struct fd *fd, const async_data_t *data )
 310 {
 311     struct async *async;
 312     struct iosb *iosb;
 313
 314     if (!(iosb = create_iosb( get_req_data(), get_req_data_size(), get_reply_max_size() )))
 315         return NULL;
 316
 317     async = create_async( fd, current, data, iosb );
 318     release_object( iosb );
 319     if (async)
 320     {
 321         if (!(async->wait_handle = alloc_handle( current->process, async, SYNCHRONIZE, 0 )))
 322         {
 323             release_object( async );
 324             return NULL;
 325         }
 326         async->direct_result = 1;
 327     }
 328     return async;
 329 }
 330
 331 /* return async object status and wait handle to client */
 332 obj_handle_t async_handoff( struct async *async, int success, data_size_t *result )
 333 {
 334     if (!success)
 335     {
 336         close_handle( async->thread->process, async->wait_handle );
 337         async->wait_handle = 0;
 338         return 0;
 339     }
 340
 341     if (get_error() != STATUS_PENDING)
 342     {
 343         /* status and data are already set and returned */
 344         async_terminate( async, get_error() );
 345     }
 346     else if (async->iosb->status != STATUS_PENDING)
 347     {
 348         /* result is already available in iosb, return it */
 349         if (async->iosb->out_data)
 350         {
 351             set_reply_data_ptr( async->iosb->out_data, async->iosb->out_size );
 352             async->iosb->out_data = NULL;
 353         }
 354     }
 355
 356     if (async->iosb->status != STATUS_PENDING)
 357     {
 358         if (result) *result = async->iosb->result;
 359         async->signaled = 1;
 360     }
 361     else
 362     {
 363         async->direct_result = 0;
 364         if (!async_is_blocking( async ))
 365         {
 366             close_handle( async->thread->process, async->wait_handle);
 367             async->wait_handle = 0;
 368         }
 369     }
 370     set_error( async->iosb->status );
 371     return async->wait_handle;
 372 }
 373
 374 /* set the timeout of an async operation */
 375 void async_set_timeout( struct async *async, timeout_t timeout, unsigned int status )
 376 {
 377     if (async->timeout) remove_timeout_user( async->timeout );
 378     if (timeout != TIMEOUT_INFINITE) async->timeout = add_timeout_user( timeout, async_timeout, async );
 379     else async->timeout = NULL;
 380     async->timeout_status = status;
 381 }
 382
 383 static void add_async_completion( struct async *async, apc_param_t cvalue, unsigned int status,
 384                                   apc_param_t information )
 385 {
 386     struct fd *fd = async->queue ? async->queue->fd : async->fd;
 387
 388     if (fd)
 389     {
 390         apc_param_t ckey;
 391         struct completion *completion = fd_get_completion( fd, &ckey );
 392
 393         if (completion)
 394         {
 395             add_completion( completion, ckey, cvalue, status, information );
 396             release_object( completion );
 397         }
 398     }
 399     else if (async->queue && async->queue->completion)
 400         add_completion( async->queue->completion, async->queue->comp_key, cvalue, status, information );
 401 }
 402
 403 /* store the result of the client-side async callback */
 404 void async_set_result( struct object *obj, unsigned int status, apc_param_t total )
 405 {
 406     struct async *async = (struct async *)obj;
 407
 408     if (obj->ops != &async_ops) return;  /* in case the client messed up the APC results */
 409
 410     assert( async->status != STATUS_PENDING );  /* it must have been woken up if we get a result */
 411
 412     if (status == STATUS_PENDING)  /* restart it */
 413     {
 414         status = async->status;
 415         async->status = STATUS_PENDING;
 416         grab_object( async );
 417
 418         if (status != STATUS_ALERTED)  /* it was terminated in the meantime */
 419             async_terminate( async, status );
 420         else
 421             async_reselect( async );
 422     }
 423     else
 424     {
 425         if (async->timeout) remove_timeout_user( async->timeout );
 426         async->timeout = NULL;
 427         async->status = status;
 428         if (status == STATUS_MORE_PROCESSING_REQUIRED) return;  /* don't report the completion */
 429
 430         if (async->data.apc)
 431         {
 432             apc_call_t data;
 433             memset( &data, 0, sizeof(data) );
 434             data.type         = APC_USER;
 435             data.user.func    = async->data.apc;
 436             data.user.args[0] = async->data.apc_context;
 437             data.user.args[1] = async->data.iosb;
 438             data.user.args[2] = 0;
 439             thread_queue_apc( async->thread, NULL, &data );
 440         }
 441         else if (async->data.apc_context)
 442             add_async_completion( async, async->data.apc_context, status, total );
 443
 444         if (async->event) set_event( async->event );
 445         else if (async->fd) set_fd_signaled( async->fd, 1 );
 446         else if (async->queue && async->queue->fd) set_fd_signaled( async->queue->fd, 1 );
 447         if (!async->signaled)
 448         {
 449             async->signaled = 1;
 450             wake_up( &async->obj, 0 );
 451         }
 452     }
 453 }
 454
 455 /* check if there are any queued async operations */
 456 int async_queued( struct async_queue *queue )
 457 {
 458     return queue && list_head( &queue->queue );
 459 }
 460
 461 /* check if an async operation is waiting to be alerted */
 462 int async_waiting( struct async_queue *queue )
 463 {
 464     struct list *ptr;
 465     struct async *async;
 466
 467     if (!queue) return 0;
 468     if (!(ptr = list_head( &queue->queue ))) return 0;
 469     async = LIST_ENTRY( ptr, struct async, queue_entry );
 470     return async->status == STATUS_PENDING;
 471 }
 472
 473 static int cancel_async( struct process *process, struct object *obj, struct thread *thread, client_ptr_t iosb )
 474 {
 475     struct async *async;
 476     struct fd *fd;
 477     int woken = 0;
 478
 479 restart:
 480     LIST_FOR_EACH_ENTRY( async, &process->asyncs, struct async, process_entry )
 481     {
 482         if (async->status == STATUS_CANCELLED) continue;
 483         fd = async->queue ? async->queue->fd : async->fd;
 484         if ((!obj || (fd && get_fd_user( fd ) == obj)) &&
 485             (!thread || async->thread == thread) &&
 486             (!iosb || async->data.iosb == iosb))
 487         {
 488             async_terminate( async, STATUS_CANCELLED );
 489             woken++;
 490             goto restart;
 491         }
 492     }
 493     return woken;
 494 }
 495
 496 void cancel_process_asyncs( struct process *process )
 497 {
 498     cancel_async( process, NULL, NULL, 0 );
 499 }
 500
 501 /* wake up async operations on the queue */
 502 void async_wake_up( struct async_queue *queue, unsigned int status )
 503 {
 504     struct list *ptr, *next;
 505
 506     if (!queue) return;
 507
 508     LIST_FOR_EACH_SAFE( ptr, next, &queue->queue )
 509     {
 510         struct async *async = LIST_ENTRY( ptr, struct async, queue_entry );
 511         async_terminate( async, status );
 512         if (status == STATUS_ALERTED) break;  /* only wake up the first one */
 513     }
 514 }
 515
 516 static void iosb_dump( struct object *obj, int verbose );
 517 static void iosb_destroy( struct object *obj );
 518
 519 static const struct object_ops iosb_ops =
 520 {
 521     sizeof(struct iosb),      /* size */
 522     iosb_dump,                /* dump */
 523     no_get_type,              /* get_type */
 524     no_add_queue,             /* add_queue */
 525     NULL,                     /* remove_queue */
 526     NULL,                     /* signaled */
 527     NULL,                     /* satisfied */
 528     no_signal,                /* signal */
 529     no_get_fd,                /* get_fd */
 530     no_map_access,            /* map_access */
 531     default_get_sd,           /* get_sd */
 532     default_set_sd,           /* set_sd */
 533     no_lookup_name,           /* lookup_name */
 534     no_link_name,             /* link_name */
 535     NULL,                     /* unlink_name */
 536     no_open_file,             /* open_file */
 537     no_close_handle,          /* close_handle */
 538     iosb_destroy              /* destroy */
 539 };
 540
 541 static void iosb_dump( struct object *obj, int verbose )
 542 {
 543     assert( obj->ops == &iosb_ops );
 544     fprintf( stderr, "I/O status block\n" );
 545 }
 546
 547 static void iosb_destroy( struct object *obj )
 548 {
 549     struct iosb *iosb = (struct iosb *)obj;
 550
 551     free( iosb->in_data );
 552     free( iosb->out_data );
 553 }
 554
 555 /* allocate iosb struct */
 556 struct iosb *create_iosb( const void *in_data, data_size_t in_size, data_size_t out_size )
 557 {
 558     struct iosb *iosb;
 559
 560     if (!(iosb = alloc_object( &iosb_ops ))) return NULL;
 561
 562     iosb->status = STATUS_PENDING;
 563     iosb->result = 0;
 564     iosb->in_size = in_size;
 565     iosb->in_data = NULL;
 566     iosb->out_size = out_size;
 567     iosb->out_data = NULL;
 568
 569     if (in_size && !(iosb->in_data = memdup( in_data, in_size )))
 570     {
 571         release_object( iosb );
 572         iosb = NULL;
 573     }
 574
 575     return iosb;
 576 }
 577
 578 struct iosb *async_get_iosb( struct async *async )
 579 {
 580     return async->iosb ? (struct iosb *)grab_object( async->iosb ) : NULL;
 581 }
 582
 583 int async_is_blocking( struct async *async )
 584 {
 585     return !async->event && !async->data.apc && !async->data.apc_context;
 586 }
 587
 588 /* find the first pending async in queue */
 589 struct async *find_pending_async( struct async_queue *queue )
 590 {
 591     struct async *async;
 592     if (queue) LIST_FOR_EACH_ENTRY( async, &queue->queue, struct async, queue_entry )
 593         if (async->status == STATUS_PENDING) return (struct async *)grab_object( async );
 594     return NULL;
 595 }
 596
 597 /* cancels all async I/O */
 598 DECL_HANDLER(cancel_async)
 599 {
 600     struct object *obj = get_handle_obj( current->process, req->handle, 0, NULL );
 601     struct thread *thread = req->only_thread ? current : NULL;
 602
 603     if (obj)
 604     {
 605         int count = cancel_async( current->process, obj, thread, req->iosb );
 606         if (!count && req->iosb) set_error( STATUS_NOT_FOUND );
 607         release_object( obj );
 608     }
 609 }
 610
 611 /* get async result from associated iosb */
 612 DECL_HANDLER(get_async_result)
 613 {
 614     struct iosb *iosb = NULL;
 615     struct async *async;
 616
 617     LIST_FOR_EACH_ENTRY( async, &current->process->asyncs, struct async, process_entry )
 618         if (async->data.user == req->user_arg)
 619         {
 620             iosb = async->iosb;
 621             break;
 622         }
 623
 624     if (!iosb)
 625     {
 626         set_error( STATUS_INVALID_PARAMETER );
 627         return;
 628     }
 629
 630     if (iosb->out_data)
 631     {
 632         data_size_t size = min( iosb->out_size, get_reply_max_size() );
 633         if (size)
 634         {
 635             set_reply_data_ptr( iosb->out_data, size );
 636             iosb->out_data = NULL;
 637         }
 638     }
 639     reply->size = iosb->result;
 640     set_error( iosb->status );
 641 }