On Saturday 09 May 2009, Benjamin Herrenschmidt wrote: > This was shot down by a vast majority of people, with the outcome being > an agreement that for IORESOURCE_MEM, pci_iomap and friends must return > something that is strictly interchangeable with what ioremap would have > returned. > > That means that readl and writel must work on the output of pci_iomap() > and similar, but I don't see why __raw_writel would be excluded there, I > think it's in there too. One of the ideas was to change pci_iomap to return a special token in case of virtual devices that causes iowrite32() to do an hcall, and to just define writel() to do iowrite32(). Unfortunately, there is no __raw_iowrite32(), although I guess we could add this generically if necessary. > Direct dereference is illegal in all cases though. right. > The token returned by pci_iomap for other type of resources (IO for > example) is also only supported for use by iomap access functions > (ioreadXX/iowriteXX) , and IO ports cannot be passed directly to those > neither. That still leaves the option to let drivers pass the IORESOURCE_PVIO for its own resources under some conditions, meaning that we will only use hcalls for I/O on these drivers but not on others, as Chris explained earlier. Arnd <>< -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html