On Sun, 2009-06-21 at 13:42 -0700, Linus Torvalds wrote: > Just a heads up that I committed the patches that I sent out two months > ago to make the fault handling routines use the finer-grained fault flags > (FAULT_FLAG_xyzzy) rather than passing in a boolean for "write". > > That was originally for the NOPAGE_RETRY patches, but it's a general > cleanup too. I have this suspicion that we should extend this to > "get_user_pages()" too, instead of having those boolean "write" and > "force" flags (and GUP_FLAGS_xyzzy as opposed to FAULT_FLAGS_yyzzy). BTW. I'd like to extend these if there's no objection one of these days to also pass whether it was an exec fault, and pass the full flags to ptep_set_access_flags(). That would (finally) give us a better hook for architectures that need to do it to handle i$/d$ coherency. Right now, I go dig for the current fault type inside the current pt_regs from ptep_set_access_flags() which is positively ugly. Ben. > We should probably also get rid of the insane FOLL_xyz flags too. Right > now the code in fact depends on FOLL_WRITE being the same as > FAULT_FLAGS_WRITE, and while that is a simple dependency, it's just crazy > how we have all these different flags for what ends up often boiling down > to the same fundamental issue in the end (even if not all versions of the > flags are necessarily always valid for all uses). > > I fixed up all architectures that I noticed (at least microblaze had been > added since the original patches in April), but arch maintainers should > double-check. Arch maintainers might also want to check whether the > mindless conversion of > > 'is_write' => 'is_write ? FAULT_FLAGS_WRITE : 0' > > might perhaps be written in some more natural way (for example, maybe > you'd like to get rid of 'iswrite' as a variable entirely, and replace it > with a 'fault_flags' variable). > > It's pushed out and tested on x86-64, but it really was such a mindless > conversion that I hope it works on all architectures. But I thought I'd > better give people a shout-out regardless. > > Linus > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@xxxxxxxxxx For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a> -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
