On Thu, Aug 21, 2014 at 04:43:28PM +0100, Steve Capper wrote: > We need a mechanism to tag ptes as being special, this indicates that > no attempt should be made to access the underlying struct page * > associated with the pte. This is used by the fast_gup when operating on > ptes as it has no means to access VMAs (that also contain this > information) locklessly. > > The L_PTE_SPECIAL bit is already allocated for LPAE, this patch modifies > pte_special and pte_mkspecial to make use of it, and defines > __HAVE_ARCH_PTE_SPECIAL. > > This patch also excludes special ptes from the icache/dcache sync logic. > > Signed-off-by: Steve Capper <steve.capper@xxxxxxxxxx> Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>