[PATCH 0/4] ppc, fbdev: Clean up fbdev mmap helper

Michael Ellerman mpe at ellerman.id.au
Tue Sep 5 12:47:08 AEST 2023

Thomas Zimmermann <tzimmermann at suse.de> writes:
> Refactor fb_pgprotect() in PowerPC to work without struct file. Then
> clean up and rename fb_pgprotect(). This change has been discussed at
> [1] in the context of refactoring fbdev's mmap code.
> The first three patches adapt PowerPC's internal interfaces to
> provide a phys_mem_access_prot() that works without struct file. Neither
> the architecture code or fbdev helpers need the parameter.
> Patch 4 replaces fbdev's fb_pgprotect() with fb_pgprot_device() on
> all architectures. The new helper with its stream-lined interface
> enables more refactoring within fbdev's mmap implementation.

The content of this series is OK, but the way it's structured makes it a
real headache to merge, because it's mostly powerpc changes and then a
dependant cross architecture patch at the end.

It would be simpler if patch 4 was first and just passed file=NULL to
the powerpc helper, with an explanation that it's unused and will be
dropped in a future cleanup.

We could then put the first patch (previously patch 4) in a topic branch
that is shared between the powerpc tree and the fbdev tree, and then the
powerpc changes could be staged on top of that through the powerpc tree.


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