Re: (reposting) how to get DMA'able memory within 4GB on 64-bit m achi ne

Jens Axboe
2001-07-02T08:09:03Z

On Thu, Jun 28 2001, Alan Cox wrote:
> We will also have to address those cards that have 28/30/31 bit limits (yes
> they exist) when we start doing direct I/O for 32bits of memory - one reason
> I'm very wary of Jens patch ever being in 2.4

The patch can handle those too, FWIW. The fact that it just sets 32-bit
limit now is unrelated, and it is also just set for devices that have
been sort-of tested :-)

Anyhoo, my point is that the bounce limit is variable on a page
granularity.

--
Jens Axboe