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     unsigned int         status;          /* current status */
  45     struct timeout_user *timeout;
  46     unsigned int         timeout_status;  /* status to report upon timeout */
  47     int                  signaled;
  48     struct event        *event;
  49     async_data_t         data;            /* data for async I/O call */
  50     struct iosb         *iosb;            /* I/O status block */
  51 };
  52
  53 static void async_dump( struct object *obj, int verbose );
  54 static int async_signaled( struct object *obj, struct wait_queue_entry *entry );
  55 static void async_destroy( struct object *obj );
  56
  57 static const struct object_ops async_ops =
  58 {
  59     sizeof(struct async),      /* size */
  60     async_dump,                /* dump */
  61     no_get_type,               /* get_type */
  62     add_queue,                 /* add_queue */
  63     remove_queue,              /* remove_queue */
  64     async_signaled,            /* signaled */
  65     no_satisfied,              /* satisfied */
  66     no_signal,                 /* signal */
  67     no_get_fd,                 /* get_fd */
  68     no_map_access,             /* map_access */
  69     default_get_sd,            /* get_sd */
  70     default_set_sd,            /* set_sd */
  71     no_lookup_name,            /* lookup_name */
  72     no_link_name,              /* link_name */
  73     NULL,                      /* unlink_name */
  74     no_open_file,              /* open_file */
  75     no_close_handle,           /* close_handle */
  76     async_destroy              /* destroy */
  77 };
  78
  79
  80 struct async_queue
  81 {
  82     struct object        obj;             /* object header */
  83     struct fd           *fd;              /* file descriptor owning this queue */
  84     struct completion   *completion;      /* completion associated with a recently closed file descriptor */
  85     apc_param_t          comp_key;        /* completion key associated with a recently closed file descriptor */
  86     struct list          queue;           /* queue of async objects */
  87 };
  88
  89 static void async_queue_dump( struct object *obj, int verbose );
  90 static void async_queue_destroy( struct object *obj );
  91
  92 static const struct object_ops async_queue_ops =
  93 {
  94     sizeof(struct async_queue),      /* size */
  95     async_queue_dump,                /* dump */
  96     no_get_type,                     /* get_type */
  97     no_add_queue,                    /* add_queue */
  98     NULL,                            /* remove_queue */
  99     NULL,                            /* signaled */
 100     NULL,                            /* satisfied */
 101     no_signal,                       /* signal */
 102     no_get_fd,                       /* get_fd */
 103     no_map_access,                   /* map_access */
 104     default_get_sd,                  /* get_sd */
 105     default_set_sd,                  /* set_sd */
 106     no_lookup_name,                  /* lookup_name */
 107     no_link_name,                    /* link_name */
 108     NULL,                            /* unlink_name */
 109     no_open_file,                    /* open_file */
 110     no_close_handle,                 /* close_handle */
 111     async_queue_destroy              /* destroy */
 112 };
 113
 114
 115 static inline void async_reselect( struct async *async )
 116 {
 117     if (async->queue && async->queue->fd) fd_reselect_async( async->queue->fd, async->queue );
 118 }
 119
 120 static void async_dump( struct object *obj, int verbose )
 121 {
 122     struct async *async = (struct async *)obj;
 123     assert( obj->ops == &async_ops );
 124     fprintf( stderr, "Async thread=%p\n", async->thread );
 125 }
 126
 127 static int async_signaled( struct object *obj, struct wait_queue_entry *entry )
 128 {
 129     struct async *async = (struct async *)obj;
 130     assert( obj->ops == &async_ops );
 131     return async->signaled;
 132 }
 133
 134 static void async_destroy( struct object *obj )
 135 {
 136     struct async *async = (struct async *)obj;
 137     assert( obj->ops == &async_ops );
 138
 139     list_remove( &async->process_entry );
 140
 141     if (async->queue)
 142     {
 143         list_remove( &async->queue_entry );
 144         async_reselect( async );
 145         release_object( async->queue );
 146     }
 147
 148     if (async->timeout) remove_timeout_user( async->timeout );
 149     if (async->event) release_object( async->event );
 150     if (async->iosb) release_object( async->iosb );
 151     release_object( async->thread );
 152 }
 153
 154 static void async_queue_dump( struct object *obj, int verbose )
 155 {
 156     struct async_queue *async_queue = (struct async_queue *)obj;
 157     assert( obj->ops == &async_queue_ops );
 158     fprintf( stderr, "Async queue fd=%p\n", async_queue->fd );
 159 }
 160
 161 static void async_queue_destroy( struct object *obj )
 162 {
 163     struct async_queue *async_queue = (struct async_queue *)obj;
 164     assert( obj->ops == &async_queue_ops );
 165     if (async_queue->completion) release_object( async_queue->completion );
 166 }
 167
 168 /* notifies client thread of new status of its async request */
 169 void async_terminate( struct async *async, unsigned int status )
 170 {
 171     assert( status != STATUS_PENDING );
 172
 173     if (async->status != STATUS_PENDING)
 174     {
 175         /* already terminated, just update status */
 176         async->status = status;
 177         return;
 178     }
 179
 180     async->status = status;
 181     if (async->iosb && async->iosb->status == STATUS_PENDING) async->iosb->status = status;
 182
 183     if (async->data.user)
 184     {
 185         apc_call_t data;
 186
 187         memset( &data, 0, sizeof(data) );
 188         data.type            = APC_ASYNC_IO;
 189         data.async_io.user   = async->data.user;
 190         data.async_io.sb     = async->data.iosb;
 191         data.async_io.status = status;
 192         thread_queue_apc( async->thread, &async->obj, &data );
 193     }
 194     else async_set_result( &async->obj, STATUS_SUCCESS, 0 );
 195
 196     async_reselect( async );
 197     if (async->queue) release_object( async );  /* so that it gets destroyed when the async is done */
 198 }
 199
 200 /* callback for timeout on an async request */
 201 static void async_timeout( void *private )
 202 {
 203     struct async *async = private;
 204
 205     async->timeout = NULL;
 206     async_terminate( async, async->timeout_status );
 207 }
 208
 209 /* create a new async queue for a given fd */
 210 struct async_queue *create_async_queue( struct fd *fd )
 211 {
 212     struct async_queue *queue = alloc_object( &async_queue_ops );
 213
 214     if (queue)
 215     {
 216         queue->fd = fd;
 217         queue->completion = NULL;
 218         list_init( &queue->queue );
 219     }
 220     return queue;
 221 }
 222
 223 /* free an async queue, cancelling all async operations */
 224 void free_async_queue( struct async_queue *queue )
 225 {
 226     if (!queue) return;
 227     if (queue->fd) queue->completion = fd_get_completion( queue->fd, &queue->comp_key );
 228     queue->fd = NULL;
 229     async_wake_up( queue, STATUS_HANDLES_CLOSED );
 230     release_object( queue );
 231 }
 232
 233 void queue_async( struct async_queue *queue, struct async *async )
 234 {
 235     async->queue = (struct async_queue *)grab_object( queue );
 236
 237     grab_object( async );
 238     list_add_tail( &queue->queue, &async->queue_entry );
 239
 240     if (queue->fd) set_fd_signaled( queue->fd, 0 );
 241 }
 242
 243 /* create an async on a given queue of a fd */
 244 struct async *create_async( struct thread *thread, const async_data_t *data, struct iosb *iosb )
 245 {
 246     struct event *event = NULL;
 247     struct async *async;
 248
 249     if (data->event && !(event = get_event_obj( thread->process, data->event, EVENT_MODIFY_STATE )))
 250         return NULL;
 251
 252     if (!(async = alloc_object( &async_ops )))
 253     {
 254         if (event) release_object( event );
 255         return NULL;
 256     }
 257
 258     async->thread  = (struct thread *)grab_object( thread );
 259     async->event   = event;
 260     async->status  = STATUS_PENDING;
 261     async->data    = *data;
 262     async->timeout = NULL;
 263     async->queue   = NULL;
 264     async->signaled = 0;
 265
 266     if (iosb) async->iosb = (struct iosb *)grab_object( iosb );
 267     else async->iosb = NULL;
 268
 269     list_add_head( &thread->process->asyncs, &async->process_entry );
 270     if (event) reset_event( event );
 271
 272     return async;
 273 }
 274
 275 /* set the timeout of an async operation */
 276 void async_set_timeout( struct async *async, timeout_t timeout, unsigned int status )
 277 {
 278     if (async->timeout) remove_timeout_user( async->timeout );
 279     if (timeout != TIMEOUT_INFINITE) async->timeout = add_timeout_user( timeout, async_timeout, async );
 280     else async->timeout = NULL;
 281     async->timeout_status = status;
 282 }
 283
 284 static void add_async_completion( struct async_queue *queue, apc_param_t cvalue, unsigned int status,
 285                                   apc_param_t information )
 286 {
 287     if (queue->fd)
 288     {
 289         apc_param_t ckey;
 290         struct completion *completion = fd_get_completion( queue->fd, &ckey );
 291
 292         if (completion)
 293         {
 294             add_completion( completion, ckey, cvalue, status, information );
 295             release_object( completion );
 296         }
 297     }
 298     else if (queue->completion) add_completion( queue->completion, queue->comp_key,
 299                                                 cvalue, status, information );
 300 }
 301
 302 /* store the result of the client-side async callback */
 303 void async_set_result( struct object *obj, unsigned int status, apc_param_t total )
 304 {
 305     struct async *async = (struct async *)obj;
 306
 307     if (obj->ops != &async_ops) return;  /* in case the client messed up the APC results */
 308
 309     assert( async->status != STATUS_PENDING );  /* it must have been woken up if we get a result */
 310
 311     if (status == STATUS_PENDING)  /* restart it */
 312     {
 313         status = async->status;
 314         async->status = STATUS_PENDING;
 315         grab_object( async );
 316
 317         if (status != STATUS_ALERTED)  /* it was terminated in the meantime */
 318             async_terminate( async, status );
 319         else
 320             async_reselect( async );
 321     }
 322     else
 323     {
 324         if (async->timeout) remove_timeout_user( async->timeout );
 325         async->timeout = NULL;
 326         async->status = status;
 327         if (status == STATUS_MORE_PROCESSING_REQUIRED) return;  /* don't report the completion */
 328
 329         if (async->queue && !async->data.apc && async->data.apc_context)
 330             add_async_completion( async->queue, async->data.apc_context, status, total );
 331         if (async->data.apc)
 332         {
 333             apc_call_t data;
 334             memset( &data, 0, sizeof(data) );
 335             data.type         = APC_USER;
 336             data.user.func    = async->data.apc;
 337             data.user.args[0] = async->data.apc_context;
 338             data.user.args[1] = async->data.iosb;
 339             data.user.args[2] = 0;
 340             thread_queue_apc( async->thread, NULL, &data );
 341         }
 342         if (async->event) set_event( async->event );
 343         else if (async->queue && async->queue->fd) set_fd_signaled( async->queue->fd, 1 );
 344         async->signaled = 1;
 345         wake_up( &async->obj, 0 );
 346     }
 347 }
 348
 349 /* check if there are any queued async operations */
 350 int async_queued( struct async_queue *queue )
 351 {
 352     return queue && list_head( &queue->queue );
 353 }
 354
 355 /* check if an async operation is waiting to be alerted */
 356 int async_waiting( struct async_queue *queue )
 357 {
 358     struct list *ptr;
 359     struct async *async;
 360
 361     if (!queue) return 0;
 362     if (!(ptr = list_head( &queue->queue ))) return 0;
 363     async = LIST_ENTRY( ptr, struct async, queue_entry );
 364     return async->status == STATUS_PENDING;
 365 }
 366
 367 static int cancel_async( struct process *process, struct object *obj, struct thread *thread, client_ptr_t iosb )
 368 {
 369     struct async *async;
 370     int woken = 0;
 371
 372 restart:
 373     LIST_FOR_EACH_ENTRY( async, &process->asyncs, struct async, process_entry )
 374     {
 375         if (async->status == STATUS_CANCELLED) continue;
 376         if ((!obj || (async->queue && async->queue->fd && get_fd_user( async->queue->fd ) == obj)) &&
 377             (!thread || async->thread == thread) &&
 378             (!iosb || async->data.iosb == iosb))
 379         {
 380             async_terminate( async, STATUS_CANCELLED );
 381             woken++;
 382             goto restart;
 383         }
 384     }
 385     return woken;
 386 }
 387
 388 void cancel_process_asyncs( struct process *process )
 389 {
 390     cancel_async( process, NULL, NULL, 0 );
 391 }
 392
 393 /* wake up async operations on the queue */
 394 void async_wake_up( struct async_queue *queue, unsigned int status )
 395 {
 396     struct list *ptr, *next;
 397
 398     if (!queue) return;
 399
 400     LIST_FOR_EACH_SAFE( ptr, next, &queue->queue )
 401     {
 402         struct async *async = LIST_ENTRY( ptr, struct async, queue_entry );
 403         async_terminate( async, status );
 404         if (status == STATUS_ALERTED) break;  /* only wake up the first one */
 405     }
 406 }
 407
 408 static void iosb_dump( struct object *obj, int verbose );
 409 static void iosb_destroy( struct object *obj );
 410
 411 static const struct object_ops iosb_ops =
 412 {
 413     sizeof(struct iosb),      /* size */
 414     iosb_dump,                /* dump */
 415     no_get_type,              /* get_type */
 416     no_add_queue,             /* add_queue */
 417     NULL,                     /* remove_queue */
 418     NULL,                     /* signaled */
 419     NULL,                     /* satisfied */
 420     no_signal,                /* signal */
 421     no_get_fd,                /* get_fd */
 422     no_map_access,            /* map_access */
 423     default_get_sd,           /* get_sd */
 424     default_set_sd,           /* set_sd */
 425     no_lookup_name,           /* lookup_name */
 426     no_link_name,             /* link_name */
 427     NULL,                     /* unlink_name */
 428     no_open_file,             /* open_file */
 429     no_close_handle,          /* close_handle */
 430     iosb_destroy              /* destroy */
 431 };
 432
 433 static void iosb_dump( struct object *obj, int verbose )
 434 {
 435     assert( obj->ops == &iosb_ops );
 436     fprintf( stderr, "I/O status block\n" );
 437 }
 438
 439 static void iosb_destroy( struct object *obj )
 440 {
 441     struct iosb *iosb = (struct iosb *)obj;
 442
 443     free( iosb->in_data );
 444     free( iosb->out_data );
 445 }
 446
 447 /* allocate iosb struct */
 448 struct iosb *create_iosb( const void *in_data, data_size_t in_size, data_size_t out_size )
 449 {
 450     struct iosb *iosb;
 451
 452     if (!(iosb = alloc_object( &iosb_ops ))) return NULL;
 453
 454     iosb->status = STATUS_PENDING;
 455     iosb->result = 0;
 456     iosb->in_size = in_size;
 457     iosb->in_data = NULL;
 458     iosb->out_size = out_size;
 459     iosb->out_data = NULL;
 460
 461     if (in_size && !(iosb->in_data = memdup( in_data, in_size )))
 462     {
 463         release_object( iosb );
 464         iosb = NULL;
 465     }
 466
 467     return iosb;
 468 }
 469
 470 struct iosb *async_get_iosb( struct async *async )
 471 {
 472     return async->iosb ? (struct iosb *)grab_object( async->iosb ) : NULL;
 473 }
 474
 475 int async_is_blocking( struct async *async )
 476 {
 477     return !async->event && !async->data.apc && !async->data.apc_context;
 478 }
 479
 480 /* find the first pending async in queue */
 481 struct async *find_pending_async( struct async_queue *queue )
 482 {
 483     struct async *async;
 484     if (queue) LIST_FOR_EACH_ENTRY( async, &queue->queue, struct async, queue_entry )
 485         if (async->status == STATUS_PENDING) return (struct async *)grab_object( async );
 486     return NULL;
 487 }
 488
 489 /* cancels all async I/O */
 490 DECL_HANDLER(cancel_async)
 491 {
 492     struct object *obj = get_handle_obj( current->process, req->handle, 0, NULL );
 493     struct thread *thread = req->only_thread ? current : NULL;
 494
 495     if (obj)
 496     {
 497         int count = cancel_async( current->process, obj, thread, req->iosb );
 498         if (!count && req->iosb) set_error( STATUS_NOT_FOUND );
 499         release_object( obj );
 500     }
 501 }
 502
 503 /* get async result from associated iosb */
 504 DECL_HANDLER(get_async_result)
 505 {
 506     struct iosb *iosb = NULL;
 507     struct async *async;
 508
 509     LIST_FOR_EACH_ENTRY( async, &current->process->asyncs, struct async, process_entry )
 510         if (async->data.user == req->user_arg)
 511         {
 512             iosb = async->iosb;
 513             break;
 514         }
 515
 516     if (!iosb)
 517     {
 518         set_error( STATUS_INVALID_PARAMETER );
 519         return;
 520     }
 521
 522     if (iosb->out_data)
 523     {
 524         data_size_t size = min( iosb->out_size, get_reply_max_size() );
 525         if (size)
 526         {
 527             set_reply_data_ptr( iosb->out_data, size );
 528             iosb->out_data = NULL;
 529         }
 530     }
 531     reply->size = iosb->result;
 532     set_error( iosb->status );
 533 }