rtems/src/regiongetsegment.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSImplClassicRegion
0007  *
0008  * @brief This source file contains the implementation of
0009  *   rtems_region_get_segment().
0010  */
0011
0012 /*
0013  *  COPYRIGHT (c) 1989-2007.
0014  *  On-Line Applications Research Corporation (OAR).
0015  *
0016  * Redistribution and use in source and binary forms, with or without
0017  * modification, are permitted provided that the following conditions
0018  * are met:
0019  * 1. Redistributions of source code must retain the above copyright
0020  *    notice, this list of conditions and the following disclaimer.
0021  * 2. Redistributions in binary form must reproduce the above copyright
0022  *    notice, this list of conditions and the following disclaimer in the
0023  *    documentation and/or other materials provided with the distribution.
0024  *
0025  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0026  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0027  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0028  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0029  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0030  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0031  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0032  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0033  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0034  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0035  * POSSIBILITY OF SUCH DAMAGE.
0036  */
0037
0038 #ifdef HAVE_CONFIG_H
0039 #include "config.h"
0040 #endif
0041
0042 #include <rtems/rtems/regionimpl.h>
0043 #include <rtems/rtems/optionsimpl.h>
0044 #include <rtems/rtems/statusimpl.h>
0045 #include <rtems/score/threadqimpl.h>
0046 #include <rtems/score/statesimpl.h>
0047
0048 static void _Region_Enqueue_callout(
0049   Thread_queue_Queue   *queue,
0050   Thread_Control       *the_thread,
0051   Per_CPU_Control      *cpu_self,
0052   Thread_queue_Context *queue_context
0053 )
0054 {
0055   Region_Control *the_region;
0056
0057   _Thread_queue_Add_timeout_ticks(
0058     queue,
0059     the_thread,
0060     cpu_self,
0061     queue_context
0062   );
0063
0064   the_region = REGION_OF_THREAD_QUEUE_QUEUE( queue );
0065   _Region_Unlock( the_region );
0066 }
0067
0068 rtems_status_code rtems_region_get_segment(
0069   rtems_id           id,
0070   uintptr_t          size,
0071   rtems_option       option_set,
0072   rtems_interval     timeout,
0073   void              **segment
0074 )
0075 {
0076   rtems_status_code  status;
0077   Region_Control    *the_region;
0078
0079   if ( segment == NULL ) {
0080     return RTEMS_INVALID_ADDRESS;
0081   }
0082
0083   *segment = NULL;
0084
0085   if ( size == 0 ) {
0086     return RTEMS_INVALID_SIZE;
0087   }
0088
0089   the_region = _Region_Get_and_lock( id );
0090
0091   if ( the_region == NULL ) {
0092     return RTEMS_INVALID_ID;
0093   }
0094
0095   if ( size > the_region->maximum_segment_size ) {
0096     status = RTEMS_INVALID_SIZE;
0097   } else {
0098     void *the_segment;
0099
0100     the_segment = _Region_Allocate_segment( the_region, size );
0101
0102     if ( the_segment != NULL ) {
0103       *segment = the_segment;
0104       status = RTEMS_SUCCESSFUL;
0105     } else if ( _Options_Is_no_wait( option_set ) ) {
0106       status = RTEMS_UNSATISFIED;
0107     } else {
0108       Thread_queue_Context  queue_context;
0109       Thread_Control       *executing;
0110
0111       _Thread_queue_Context_initialize( &queue_context );
0112       _Thread_queue_Acquire( &the_region->Wait_queue, &queue_context );
0113
0114       executing  = _Thread_Executing;
0115       executing->Wait.count           = size;
0116       executing->Wait.return_argument = segment;
0117
0118       /* FIXME: This is a home grown condition variable */
0119       _Thread_queue_Context_set_thread_state(
0120         &queue_context,
0121         STATES_WAITING_FOR_SEGMENT
0122       );
0123       _Thread_queue_Context_set_timeout_ticks( &queue_context, timeout );
0124       _Thread_queue_Context_set_enqueue_callout(
0125         &queue_context,
0126         _Region_Enqueue_callout
0127       );
0128       _Thread_queue_Enqueue(
0129         &the_region->Wait_queue.Queue,
0130         the_region->wait_operations,
0131         executing,
0132         &queue_context
0133       );
0134       return _Status_Get_after_wait( executing );
0135     }
0136   }
0137
0138   _Region_Unlock( the_region );
0139   return status;
0140 }