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
  35 struct async
  36 {
  37     struct object        obj;             /* object header */
  38     struct thread       *thread;          /* owning thread */
  39     struct list          queue_entry;     /* entry in async queue list */
  40     struct async_queue  *queue;           /* queue containing this async */
  41     unsigned int         status;          /* current status */
  42     struct timeout_user *timeout;
  43     unsigned int         timeout_status;  /* status to report upon timeout */
  44     int                  signaled;
  45     struct event        *event;
  46     async_data_t         data;            /* data for async I/O call */
  47 };
  48
  49 static void async_dump( struct object *obj, int verbose );
  50 static int async_signaled( struct object *obj, struct wait_queue_entry *entry );
  51 static void async_destroy( struct object *obj );
  52
  53 static const struct object_ops async_ops =
  54 {
  55     sizeof(struct async),      /* size */
  56     async_dump,                /* dump */
  57     no_get_type,               /* get_type */
  58     add_queue,                 /* add_queue */
  59     remove_queue,              /* remove_queue */
  60     async_signaled,            /* signaled */
  61     no_satisfied,              /* satisfied */
  62     no_signal,                 /* signal */
  63     no_get_fd,                 /* get_fd */
  64     no_map_access,             /* map_access */
  65     default_get_sd,            /* get_sd */
  66     default_set_sd,            /* set_sd */
  67     no_lookup_name,            /* lookup_name */
  68     no_link_name,              /* link_name */
  69     NULL,                      /* unlink_name */
  70     no_open_file,              /* open_file */
  71     no_close_handle,           /* close_handle */
  72     async_destroy              /* destroy */
  73 };
  74
  75
  76 struct async_queue
  77 {
  78     struct object        obj;             /* object header */
  79     struct fd           *fd;              /* file descriptor owning this queue */
  80     struct completion   *completion;      /* completion associated with a recently closed file descriptor */
  81     apc_param_t          comp_key;        /* completion key associated with a recently closed file descriptor */
  82     struct list          queue;           /* queue of async objects */
  83 };
  84
  85 static void async_queue_dump( struct object *obj, int verbose );
  86 static void async_queue_destroy( struct object *obj );
  87
  88 static const struct object_ops async_queue_ops =
  89 {
  90     sizeof(struct async_queue),      /* size */
  91     async_queue_dump,                /* dump */
  92     no_get_type,                     /* get_type */
  93     no_add_queue,                    /* add_queue */
  94     NULL,                            /* remove_queue */
  95     NULL,                            /* signaled */
  96     NULL,                            /* satisfied */
  97     no_signal,                       /* signal */
  98     no_get_fd,                       /* get_fd */
  99     no_map_access,                   /* map_access */
 100     default_get_sd,                  /* get_sd */
 101     default_set_sd,                  /* set_sd */
 102     no_lookup_name,                  /* lookup_name */
 103     no_link_name,                    /* link_name */
 104     NULL,                            /* unlink_name */
 105     no_open_file,                    /* open_file */
 106     no_close_handle,                 /* close_handle */
 107     async_queue_destroy              /* destroy */
 108 };
 109
 110
 111 static inline void async_reselect( struct async *async )
 112 {
 113     if (async->queue->fd) fd_reselect_async( async->queue->fd, async->queue );
 114 }
 115
 116 static void async_dump( struct object *obj, int verbose )
 117 {
 118     struct async *async = (struct async *)obj;
 119     assert( obj->ops == &async_ops );
 120     fprintf( stderr, "Async thread=%p\n", async->thread );
 121 }
 122
 123 static int async_signaled( struct object *obj, struct wait_queue_entry *entry )
 124 {
 125     struct async *async = (struct async *)obj;
 126     assert( obj->ops == &async_ops );
 127     return async->signaled;
 128 }
 129
 130 static void async_destroy( struct object *obj )
 131 {
 132     struct async *async = (struct async *)obj;
 133     assert( obj->ops == &async_ops );
 134
 135     list_remove( &async->queue_entry );
 136     async_reselect( async );
 137
 138     if (async->timeout) remove_timeout_user( async->timeout );
 139     if (async->event) release_object( async->event );
 140     release_object( async->queue );
 141     release_object( async->thread );
 142 }
 143
 144 static void async_queue_dump( struct object *obj, int verbose )
 145 {
 146     struct async_queue *async_queue = (struct async_queue *)obj;
 147     assert( obj->ops == &async_queue_ops );
 148     fprintf( stderr, "Async queue fd=%p\n", async_queue->fd );
 149 }
 150
 151 static void async_queue_destroy( struct object *obj )
 152 {
 153     struct async_queue *async_queue = (struct async_queue *)obj;
 154     assert( obj->ops == &async_queue_ops );
 155     if (async_queue->completion) release_object( async_queue->completion );
 156 }
 157
 158 /* notifies client thread of new status of its async request */
 159 void async_terminate( struct async *async, unsigned int status )
 160 {
 161     assert( status != STATUS_PENDING );
 162
 163     if (async->status != STATUS_PENDING)
 164     {
 165         /* already terminated, just update status */
 166         async->status = status;
 167         return;
 168     }
 169
 170     async->status = status;
 171
 172     if (async->data.callback)
 173     {
 174         apc_call_t data;
 175
 176         memset( &data, 0, sizeof(data) );
 177         data.type            = APC_ASYNC_IO;
 178         data.async_io.func   = async->data.callback;
 179         data.async_io.user   = async->data.arg;
 180         data.async_io.sb     = async->data.iosb;
 181         data.async_io.status = status;
 182         thread_queue_apc( async->thread, &async->obj, &data );
 183     }
 184     else async_set_result( &async->obj, STATUS_SUCCESS, 0, 0, 0 );
 185
 186     async_reselect( async );
 187     release_object( async );  /* so that it gets destroyed when the async is done */
 188 }
 189
 190 /* callback for timeout on an async request */
 191 static void async_timeout( void *private )
 192 {
 193     struct async *async = private;
 194
 195     async->timeout = NULL;
 196     async_terminate( async, async->timeout_status );
 197 }
 198
 199 /* create a new async queue for a given fd */
 200 struct async_queue *create_async_queue( struct fd *fd )
 201 {
 202     struct async_queue *queue = alloc_object( &async_queue_ops );
 203
 204     if (queue)
 205     {
 206         queue->fd = fd;
 207         queue->completion = NULL;
 208         list_init( &queue->queue );
 209     }
 210     return queue;
 211 }
 212
 213 /* free an async queue, cancelling all async operations */
 214 void free_async_queue( struct async_queue *queue )
 215 {
 216     if (!queue) return;
 217     if (queue->fd) queue->completion = fd_get_completion( queue->fd, &queue->comp_key );
 218     queue->fd = NULL;
 219     async_wake_up( queue, STATUS_HANDLES_CLOSED );
 220     release_object( queue );
 221 }
 222
 223 /* create an async on a given queue of a fd */
 224 struct async *create_async( struct thread *thread, struct async_queue *queue, const async_data_t *data )
 225 {
 226     struct event *event = NULL;
 227     struct async *async;
 228
 229     if (data->event && !(event = get_event_obj( thread->process, data->event, EVENT_MODIFY_STATE )))
 230         return NULL;
 231
 232     if (!(async = alloc_object( &async_ops )))
 233     {
 234         if (event) release_object( event );
 235         return NULL;
 236     }
 237
 238     async->thread  = (struct thread *)grab_object( thread );
 239     async->event   = event;
 240     async->status  = STATUS_PENDING;
 241     async->data    = *data;
 242     async->timeout = NULL;
 243     async->queue   = (struct async_queue *)grab_object( queue );
 244     async->signaled = 0;
 245
 246     list_add_tail( &queue->queue, &async->queue_entry );
 247     grab_object( async );
 248
 249     if (queue->fd) set_fd_signaled( queue->fd, 0 );
 250     if (event) reset_event( event );
 251     return async;
 252 }
 253
 254 /* set the timeout of an async operation */
 255 void async_set_timeout( struct async *async, timeout_t timeout, unsigned int status )
 256 {
 257     if (async->timeout) remove_timeout_user( async->timeout );
 258     if (timeout != TIMEOUT_INFINITE) async->timeout = add_timeout_user( timeout, async_timeout, async );
 259     else async->timeout = NULL;
 260     async->timeout_status = status;
 261 }
 262
 263 static void add_async_completion( struct async_queue *queue, apc_param_t cvalue, unsigned int status,
 264                                   apc_param_t information )
 265 {
 266     if (queue->fd)
 267     {
 268         apc_param_t ckey;
 269         struct completion *completion = fd_get_completion( queue->fd, &ckey );
 270
 271         if (completion)
 272         {
 273             add_completion( completion, ckey, cvalue, status, information );
 274             release_object( completion );
 275         }
 276     }
 277     else if (queue->completion) add_completion( queue->completion, queue->comp_key,
 278                                                 cvalue, status, information );
 279 }
 280
 281 /* store the result of the client-side async callback */
 282 void async_set_result( struct object *obj, unsigned int status, apc_param_t total,
 283                        client_ptr_t apc, client_ptr_t apc_arg )
 284 {
 285     struct async *async = (struct async *)obj;
 286
 287     if (obj->ops != &async_ops) return;  /* in case the client messed up the APC results */
 288
 289     assert( async->status != STATUS_PENDING );  /* it must have been woken up if we get a result */
 290
 291     if (status == STATUS_PENDING)  /* restart it */
 292     {
 293         status = async->status;
 294         async->status = STATUS_PENDING;
 295         grab_object( async );
 296
 297         if (status != STATUS_ALERTED)  /* it was terminated in the meantime */
 298             async_terminate( async, status );
 299         else
 300             async_reselect( async );
 301     }
 302     else
 303     {
 304         if (async->timeout) remove_timeout_user( async->timeout );
 305         async->timeout = NULL;
 306         async->status = status;
 307         if (status == STATUS_MORE_PROCESSING_REQUIRED) return;  /* don't report the completion */
 308
 309         if (async->data.cvalue) add_async_completion( async->queue, async->data.cvalue, status, total );
 310         if (apc)
 311         {
 312             apc_call_t data;
 313             memset( &data, 0, sizeof(data) );
 314             data.type         = APC_USER;
 315             data.user.func    = apc;
 316             data.user.args[0] = apc_arg;
 317             data.user.args[1] = async->data.iosb;
 318             data.user.args[2] = 0;
 319             thread_queue_apc( async->thread, NULL, &data );
 320         }
 321         if (async->event) set_event( async->event );
 322         else if (async->queue->fd) set_fd_signaled( async->queue->fd, 1 );
 323         async->signaled = 1;
 324         wake_up( &async->obj, 0 );
 325     }
 326 }
 327
 328 /* check if there are any queued async operations */
 329 int async_queued( struct async_queue *queue )
 330 {
 331     return queue && list_head( &queue->queue );
 332 }
 333
 334 /* check if an async operation is waiting to be alerted */
 335 int async_waiting( struct async_queue *queue )
 336 {
 337     struct list *ptr;
 338     struct async *async;
 339
 340     if (!queue) return 0;
 341     if (!(ptr = list_head( &queue->queue ))) return 0;
 342     async = LIST_ENTRY( ptr, struct async, queue_entry );
 343     return async->status == STATUS_PENDING;
 344 }
 345
 346 int async_wake_up_by( struct async_queue *queue, struct process *process,
 347                       struct thread *thread, client_ptr_t iosb, unsigned int status )
 348 {
 349     struct list *ptr, *next;
 350     int woken = 0;
 351
 352     if (!queue || (!process && !thread && !iosb)) return 0;
 353
 354     LIST_FOR_EACH_SAFE( ptr, next, &queue->queue )
 355     {
 356         struct async *async = LIST_ENTRY( ptr, struct async, queue_entry );
 357         if ( (!process || async->thread->process == process) &&
 358              (!thread || async->thread == thread) &&
 359              (!iosb || async->data.iosb == iosb) )
 360         {
 361             async_terminate( async, status );
 362             woken++;
 363         }
 364     }
 365     return woken;
 366 }
 367
 368 /* wake up async operations on the queue */
 369 void async_wake_up( struct async_queue *queue, unsigned int status )
 370 {
 371     struct list *ptr, *next;
 372
 373     if (!queue) return;
 374
 375     LIST_FOR_EACH_SAFE( ptr, next, &queue->queue )
 376     {
 377         struct async *async = LIST_ENTRY( ptr, struct async, queue_entry );
 378         async_terminate( async, status );
 379         if (status == STATUS_ALERTED) break;  /* only wake up the first one */
 380     }
 381 }