Re: Allocating and accessing physically contiguous memory in user mode in WinCE 6.0 Beta

Hi again,

Very interresting discussion...
Is it possible to have a example (pseudo code) of starting a user mode
drivers from kernel
and
how to set protected registry key (syntax)

regards

"Steve Maillet (eMVP)" <nospam1@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:%235HpVYd%23GHA.2180@xxxxxxxxxxxxxxxxxxxxxxx
Do you mean that there is no way to allocate and use a physically
contiguous memory region from user mode in 6.0 beta ?
"no way" is a bit strong a phrase and not quite true. It's generally true
for normal processes. However CE 6 supports the concept of User mode
drivers which operate in the context of a user mode process that is
created by the kernel. This process can call the CEDDK functions that do
allocations and hardware access as needed and the kernel will allow the
access to a set of addresses defined by a protected registry key created
by the device OEM. So do what should have been driver level functionality
in your application doesn't really fit the CE6 memory/security model.
However, there is a theoretical alternative that is pretty close. The
process that the kernel starts for user mode drivers is something that
you, the OEM, can specify! Thus you can alter your application to load as
the user mode driver host process and then it ends up with access to the
APIs in CEDDK for mapping hardware etc...


--
Steve Maillet
EmbeddedFusion
www.EmbeddedFusion.com
smaillet at EmbeddedFusion dot com




.

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