Re: [PATCH -mm -v4 1/3] i386/x86_64 boot: setup data

From: Nick Piggin
Date: Tue Oct 09 2007 - 03:57:22 EST


On Tuesday 09 October 2007 16:40, Huang, Ying wrote:

> +unsigned long copy_from_phys(void *to, unsigned long from_phys,
> + unsigned long n)
> +{
> + struct page *page;
> + void *from;
> + unsigned long remain = n, offset, trunck;
> +
> + while (remain) {
> + page = pfn_to_page(from_phys >> PAGE_SHIFT);
> + from = kmap_atomic(page, KM_USER0);
> + offset = from_phys & ~PAGE_MASK;
> + if (remain > PAGE_SIZE - offset)
> + trunck = PAGE_SIZE - offset;
> + else
> + trunck = remain;
> + memcpy(to, from + offset, trunck);
> + kunmap_atomic(from, KM_USER0);
> + to += trunck;
> + from_phys += trunck;
> + remain -= trunck;
> + }
> + return n;
> +}


I suppose that's not unreasonable to put in mm/memory.c, although
it's not really considered a problem to do this kind of stuff in
a low level arch file...

You have no kernel virtual mapping for the source data?

Should it be __init?

Care to add a line of documentation if you keep it in mm/memory.c?

Thanks,
Nick
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/