Re: [PATCH 0/2] vmalloc: Introduce vmap_file()

From: Christoph Hellwig
Date: Fri Jan 31 2025 - 02:10:52 EST


On Thu, Jan 30, 2025 at 04:18:04PM -0800, Vishal Moola (Oracle) wrote:
> Currently, users have to call vmap() or vmap_pfn() to map pages to
> kernel virtual space. vmap() requires the page references, and
> vmap_pfn() requires page pfns. If we have a file but no page references,
> we have to do extra work to map them.
>
> Create a function, vmap_file(), to map a specified range of a given
> file to kernel virtual space. Also convert a user that benefits from
> vmap_file().

As far as I can tell there is exatly one user that maps file pages
into vmalloc space. It's a pretty odd thing to do, so figuring out
a way to get rid of that might be a better use of time.