[PATCH 1/6] libmm-score-api. The high-level libmm API should be used by applications. It helps developers to manage memory by setting generic and target-independent protection and cache attributes for a region that has a start address, length, and desired memory attributes.

[Gedare Bloom]

On Fri, Sep 13, 2013 at 11:27 AM, Sebastian Huber
<sebastian.huber at embedded-brains.de> wrote:
> On 2013-09-12 08:59, Hesham AL-Matary wrote:
>>
>> +/**
>> + * @brief _Memory_management_Region Flags defs
>> + */
>> +
>> +#define RTEMS_MM_REGION_BIT_READ        0
>> +#define RTEMS_MM_REGION_BIT_WRITE       1
>> +#define RTEMS_MM_REGION_BIT_EXECUTE     2
>> +#define RTEMS_MM_REGION_BIT_CACHE       3
>> +#define RTEMS_MM_REGION_BIT_DEVICE      4
>> +#define RTEMS_MM_REGION_BIT_SHARED      5
>> +
>> +#define RTEMS_MM_REGION_READ    (1U << RTEMS_MM_REGION_BIT_READ)
>> +#define RTEMS_MM_REGION_WRITE   (1U << RTEMS_MM_REGION_BIT_WRITE)
>> +#define RTEMS_MM_REGION_EXECUTE (1U << RTEMS_MM_REGION_BIT_EXECUTE)
>> +#define RTEMS_MM_REGION_CACHE   (1U << RTEMS_MM_REGION_BIT_CACHE)
>> +#define RTEMS_MM_REGION_DEVICE  (1U << RTEMS_MM_REGION_BIT_DEVICE)
>> +#define RTEMS_MM_REGION_SHARED  (1U << RTEMS_MM_REGION_BIT_SHARED)
>
>
> I suggested to use such a schema, but now I am no longer sure if this was a
> good idea.
>
> What is the use case and benefit of this libmm?  Currently I see some
> low-level changes, but what is the application or kernel level use case?
>
The immediate goal would be to support POSIX mprotect on BSPs that can
(and to ignore it on those that don't). Other benefits may come in the
future, as we can consider how real-time memory protection might be
employed by applications.

Currently we do not need this high-level interface, until mprotect shows up.

-Gedare

> --
> Sebastian Huber, embedded brains GmbH
>
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>
> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
>
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