Re: [PATCH v2] mm: Add MREMAP_DONTUNMAP to mremap().

[Kirill A. Shutemov]

On Sun, Feb 02, 2020 at 05:17:53AM +0100, Brian Geffon wrote:
> On Wed, Jan 29, 2020 at 11:46 AM Kirill A. Shutemov
> <kirill@xxxxxxxxxxxxx> wrote:
> > Any better options for the flag name? (I have none)
> 
> The other option is that it's broken up into two new flags the first
> MREMAP_MUSTMOVE which can be used regardless of whether or not you're
> leaving the original mapping mapped. This would do exactly what it
> describes: move the mapping to a new address with or without
> MREMAP_FIXED, this keeps consistency with MAYMOVE.
> 
> The second flag would be the new MREMAP_DONTUNMAP flag which requires
> MREMAP_MUSTMOVE, again with or without MREMAP_FIXED.
> 
> What are your thoughts on this?

Sounds reasonable.

MREMAP_DONTUNMAP doesn't really convey that you move pages to the new
mapping, but leave empty mapping behind. But I guess there's only so much
you can encode into the name. (Patch to the man page should do the rest)

-- 
 Kirill A. Shutemov