On Fri, May 02, 2014 at 06:07:45PM +0100, Will Deacon wrote: > On Fri, May 02, 2014 at 04:51:59PM +0100, Catalin Marinas wrote: > > The primary aim of this patchset is to remove the pgprot_default and > > prot_sect_default global variables and rely strictly on predefined > > values. The original goal was to be able to run SMP kernels on UP > > hardware by not setting the Shareability bit. However, it is unlikely to > > see UP ARMv8 hardware and even if we do, the Shareability bit is no > > longer assumed to disable cacheable accesses. > > > > A side effect is that the device mappings now have the Shareability > > attribute set. The hardware, however, should ignore it since Device > > accesses are always Outer Shareable. > > > > Following the removal of the two global variables, there is some PROT_* > > macro reshuffling and cleanup, including the __PAGE_* macros (replaced > > by PAGE_*). > > [...] > > > +#define PAGE_NONE __pgprot(((_PAGE_DEFAULT) & ~PTE_TYPE_MASK) | PTE_PROT_NONE | PTE_PXN | PTE_UXN) > > +#define PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE) > > +#define PAGE_SHARED_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_WRITE) > > +#define PAGE_COPY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN) > > +#define PAGE_COPY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN) > > +#define PAGE_READONLY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN) > > +#define PAGE_READONLY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN) > > +#define PAGE_EXECONLY __pgprot(_PAGE_DEFAULT | PTE_NG | PTE_PXN) > > Could you build the non-exec versions in terms of the exec versions? The > difference is just the addition of PTE_UXN, and it would make this easier to > read. I think it still looks nicer this way. If we are writing one in terms of the other we have to use pgprot_val() to decompose the __pgprot() returned type. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-arm-kernel