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