Re: Inefficient PCI DMA usage (was: [experimental patch] UHCI updates)

Johannes Erdfelt (
Sun, 21 Jan 2001 12:37:31 -0500

On Sat, Jan 20, 2001, Russell King <> wrote:
> Johannes Erdfelt writes:
> > They need to be visible via DMA. They need to be 16 byte aligned. We
> > also have QH's which have similar requirements, but we don't use as many
> > of them.
> Can we get away from the "16 byte aligned" and make it "n byte aligned"?
> I believe that slab already has support for this?

If you look at the part of the message that I quoted and you cut off,
the requirements for UHCI are the data structures MUST be 16 byte aligned.

I don't mind if the API is more generalized, but those are the
requirements that were asked about in this specific case.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at