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