On Tuesday 09 October 2007 18:22, Huang, Ying wrote: > On Tue, 2007-10-09 at 01:25 +1000, Nick Piggin wrote: > > On Tuesday 09 October 2007 16:40, Huang, Ying wrote: > > > +unsigned long copy_from_phys(void *to, unsigned long from_phys, > > > + unsigned long 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? > > On 32-bit platform such as i386. Some memory zones have no kernel > virtual mapping (highmem region etc). I'm just wondering whether you really need to access highmem in boot code... > So I think this may be useful as a > universal way to access physical memory. But it can be more efficient to > implement it in arch file for some arch. Should this implementation be > used as a fall back implementation with attribute "weak"? Definitely on most architectures it would just amount to memcpy(dst, __va(phys), n);, right? However I don't know if it's worth the trouble of overriding it unless there is some non-__init user of it. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
