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