Changes between Version 5 and Version 6 of TBR/UserApp/MMU_Context


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Timestamp:
May 30, 2009, 1:58:39 PM (10 years ago)
Author:
Aanjhan
Comment:

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  • TBR/UserApp/MMU_Context

    v5 v6  
    11= MMU Context =
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    3 
    4 An MMU context is a data structure containing information wrt the process. The data structure would look something like the below.
    5 
    6 A create_mmu_context() function would result in populating this data structure.
     3==  Access Lookup Table (ALUT)  ==
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    9 [[Image(mmu_context_struct.jpg)]]
     6The entire address space is split up into various zones with various access attributes like Read only, Full access etc. This information is stored in a look up table inside the cpukit level of the RTEMS architecture. The data structure would have the following information stored. At the beginning we would have this as a static LUT but in the longer vision of the project it could be dynamically updated depending on the task.
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    11 The main focus now would be on having a single MMU context for the entire process working. One could have additional services to map an area of "private" memory on a per task basis. This MMU context shall be modified using the mmap* and shm* application calls.
    12 
    13 The design must allow for possibly RTEMS specific calls at application level for additional capabilities also.
     8{| class="wikitable" border="1"
     9|-
     10!  Address Pointer
     11!  Address Space Length
     12!  Access Attribute
     13|}