On 6/17/22 13:30, hch@xxxxxxxxxxxxx wrote:
> On Fri, Jun 17, 2022 at 05:48:11AM +0000, Christophe Leroy wrote:
>> Is it a good idea to duplicate vm_get_page_prot() in each architecture ?
>
> It is a completely trivial array index. And I really like the idea
> of not having the protection_map in common code - it really is an
> implementation detail. But what we could do is something like
>
> #define DECLARE_VM_GET_PAGE_PROT \
> pgprot_t vm_get_page_prot(unsigned long vm_flags) \
> { \
> return protection_map[vm_flags & \
> (VM_READ | VM_WRITE | VM_EXEC | VM_SHARED)]; \
> } \
> EXPORT_SYMBOL(vm_get_page_prot);
>
> as a helper for the architectures.
Agreed, this will ensure the exact same implementation for all platforms
(except those custom vm_get_page_prot), without deviations and mistakes.
