Re: [PATCHv2 1/9] mm: Introduce new vm_insert_range and vm_insert_range_buggy API

From: Heiko Stuebner
Date: Thu Jan 31 2019 - 07:35:02 EST


Am Donnerstag, 31. Januar 2019, 13:31:52 CET schrieb Souptick Joarder:
> On Thu, Jan 31, 2019 at 5:37 PM Heiko Stuebner <heiko@xxxxxxxxx> wrote:
> >
> > Am Donnerstag, 31. Januar 2019, 04:08:12 CET schrieb Souptick Joarder:
> > > Previouly drivers have their own way of mapping range of
> > > kernel pages/memory into user vma and this was done by
> > > invoking vm_insert_page() within a loop.
> > >
> > > As this pattern is common across different drivers, it can
> > > be generalized by creating new functions and use it across
> > > the drivers.
> > >
> > > vm_insert_range() is the API which could be used to mapped
> > > kernel memory/pages in drivers which has considered vm_pgoff
> > >
> > > vm_insert_range_buggy() is the API which could be used to map
> > > range of kernel memory/pages in drivers which has not considered
> > > vm_pgoff. vm_pgoff is passed default as 0 for those drivers.
> > >
> > > We _could_ then at a later "fix" these drivers which are using
> > > vm_insert_range_buggy() to behave according to the normal vm_pgoff
> > > offsetting simply by removing the _buggy suffix on the function
> > > name and if that causes regressions, it gives us an easy way to revert.
> > >
> > > Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx>
> > > Suggested-by: Russell King <linux@xxxxxxxxxxxxxxx>
> > > Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> >
> > hmm, I'm missing a changelog here between v1 and v2.
> > Nevertheless I managed to test v1 on Rockchip hardware
> > and display is still working, including talking to Lima via prime.
> >
> > So if there aren't any big changes for v2, on Rockchip
> > Tested-by: Heiko Stuebner <heiko@xxxxxxxxx>
>
> Change log is available in [0/9].
> Patch [1/9] & [4/9] have no changes between v1 -> v2.

I never seem to get your cover-letters, so didn't see that, sorry.

But great that there weren't changes then :-)

Heiko