Re: How to map high memory for block io

Pierre Ossman
2006-01-27T20:12:20Z

Russell King wrote:

> >
> > I don't see what the problem is. A sg entry is a list of struct page
> > pointers, an offset, and a size. As such, it can't describe a transfer
> > which crosses a page because such a structure does not imply that one
> > struct page follows another struct page.
> >
> >
>

If the pages do not strictly follow each other then there is a lot of
broken code in the kernel. drivers/mmc/mmci.c and drivers/block/ub.c
being two occurences since both assume they can access the entire entry
through a single mapping.

Rgds
Pierre