Re: [PATCH v6 3/5] mm: introduce mmap3 for safely defining new mmap flags

[Kirill A. Shutemov]

On Fri, Aug 25, 2017 at 09:02:36AM -0700, Christoph Hellwig wrote:
> On Fri, Aug 25, 2017 at 06:58:03PM +0300, Kirill A. Shutemov wrote:
> > Not all archs are ready for this:
> > 
> > arch/parisc/include/uapi/asm/mman.h:#define MAP_TYPE    0x03            /* Mask for type of mapping */
> > arch/parisc/include/uapi/asm/mman.h:#define MAP_FIXED   0x04            /* Interpret addr exactly */
> 
> I'd be happy to say that we should not care about parisc for
> persistent memory.  We'll just have to find a way to exclude
> parisc without making life too ugly.

I don't think creapling mmap() interface for one arch is the right way to
go. I think the interface should be universal.

I may imagine MAP_DIRECT can be useful not only for persistent memory.
For tmpfs instead of mlock()?

-- 
 Kirill A. Shutemov