Re: IO space memcpy support for userspace.

From: Carlos O'Donell
Date: Fri Dec 05 2008 - 12:32:21 EST

On Thu, Dec 4, 2008 at 10:40 PM, Dave Airlie <airlied@xxxxxxxxx> wrote:
> I'm sure this has come up before and I'm sure I'll either wish I never
> posted this or someone will show me the crisp corpse of the last guy
> who suggested it.

Do you plan to prevent the compiler from issuing the same sorts of
instructions that might appear in an optimized memcpy?

Isn't it dangerous to have memory that doesn't behave like normal
memory, and yet try to treat it like normal memory?

This mismatch of abstractions is a warning that must not be ignored.

IMHO you need a thin library with a new API (adding support for HAL
would be a clever way to check for PCI devices and perhaps even

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