On Mon, 3 Mar 2008, Jared Hulbert wrote: > > By 1:1 you mean virtual + offset == physical + offset right? Right. It's a special case, and it's an important special case because it's the only one that is fast to do. It's not very common, but it's common enough that it's worth doing. That said, xip should probably never have used virt_to_phys() in the first place. It should be limited to purely architecture-specific memory management routines. [ There's a number of drivers that need "physical" addresses for DMA, and that use virt_to_phys, but they should use the DMA interfaces that do this right, and even for legacy things that don't use the proper DMA allocator things virt_to_phys is wrong, because it's about _bus_ addresses, not CPU physical addresses. Only architecture code can know when the two actually mean the same thing ] Quite frankly, I think it's totally wrong to use kernel-virtual addresses in those interfaces in first place. Either you use "struct page *" or you use a pfn number. Nothing else is simply valid. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
