1 | /** |
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2 | * @file |
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3 | * |
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4 | * @brief RTEMS Get Region Segment |
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5 | * @ingroup ClassicRegion |
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6 | */ |
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7 | |
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8 | /* |
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9 | * COPYRIGHT (c) 1989-2007. |
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10 | * On-Line Applications Research Corporation (OAR). |
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11 | * |
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12 | * The license and distribution terms for this file may be |
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13 | * found in the file LICENSE in this distribution or at |
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14 | * http://www.rtems.org/license/LICENSE. |
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15 | */ |
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16 | |
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17 | #if HAVE_CONFIG_H |
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18 | #include "config.h" |
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19 | #endif |
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20 | |
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21 | #include <rtems/rtems/regionimpl.h> |
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22 | #include <rtems/rtems/optionsimpl.h> |
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23 | #include <rtems/rtems/statusimpl.h> |
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24 | #include <rtems/score/threadqimpl.h> |
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25 | #include <rtems/score/statesimpl.h> |
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26 | |
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27 | rtems_status_code rtems_region_get_segment( |
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28 | rtems_id id, |
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29 | uintptr_t size, |
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30 | rtems_option option_set, |
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31 | rtems_interval timeout, |
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32 | void **segment |
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33 | ) |
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34 | { |
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35 | rtems_status_code status; |
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36 | Region_Control *the_region; |
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37 | |
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38 | if ( segment == NULL ) { |
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39 | return RTEMS_INVALID_ADDRESS; |
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40 | } |
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41 | |
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42 | *segment = NULL; |
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43 | |
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44 | if ( size == 0 ) { |
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45 | return RTEMS_INVALID_SIZE; |
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46 | } |
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47 | |
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48 | the_region = _Region_Get_and_lock( id ); |
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49 | |
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50 | if ( the_region == NULL ) { |
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51 | return RTEMS_INVALID_ID; |
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52 | } |
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53 | |
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54 | if ( size > the_region->maximum_segment_size ) { |
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55 | status = RTEMS_INVALID_SIZE; |
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56 | } else { |
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57 | void *the_segment; |
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58 | |
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59 | the_segment = _Region_Allocate_segment( the_region, size ); |
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60 | |
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61 | if ( the_segment != NULL ) { |
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62 | *segment = the_segment; |
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63 | status = RTEMS_SUCCESSFUL; |
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64 | } else if ( _Options_Is_no_wait( option_set ) ) { |
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65 | status = RTEMS_UNSATISFIED; |
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66 | } else { |
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67 | Per_CPU_Control *cpu_self; |
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68 | Thread_Control *executing; |
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69 | |
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70 | /* |
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71 | * Switch from using the memory allocation mutex to using a |
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72 | * dispatching disabled critical section. We have to do this |
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73 | * because this thread is going to block. |
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74 | */ |
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75 | /* FIXME: This is a home grown condition variable */ |
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76 | cpu_self = _Thread_Dispatch_disable(); |
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77 | _Region_Unlock( the_region ); |
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78 | |
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79 | executing = _Per_CPU_Get_executing( cpu_self ); |
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80 | |
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81 | executing->Wait.count = size; |
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82 | executing->Wait.return_argument = segment; |
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83 | |
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84 | _Thread_queue_Enqueue( |
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85 | &the_region->Wait_queue, |
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86 | the_region->wait_operations, |
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87 | executing, |
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88 | STATES_WAITING_FOR_SEGMENT, |
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89 | timeout |
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90 | ); |
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91 | |
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92 | _Thread_Dispatch_enable( cpu_self ); |
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93 | |
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94 | return _Status_Get_after_wait( executing ); |
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95 | } |
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96 | } |
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97 | |
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98 | _Region_Unlock( the_region ); |
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99 | return status; |
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100 | } |
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