Re: [PATCH v3 1/6] set_memory: add number of pages parameter to set_direct_map APIs

[Mike Rapoport <rppt@kernel.org>]

On Thu, Sep 17, 2026 at 08:11:22PM +0200, Kevin Brodsky wrote:
> On 03/09/2026 11:28, Mike Rapoport (Microsoft) wrote:
> > When set_direct_map APIs were introduced by the commit d253ca0c3865
> > ("x86/mm/cpa: Add set_direct_map_*() functions") the single page
> > parameter made sense because the initial callers (vmalloc and
> > hibernation) had sets of unsorted struct pages that required changes of
> > their mappings in the direct map.
> >
> > Since there is an increasing demand for direct map manipulation and it
> > is also desirable to be able to update larger physically contiguous
> > mappings, for example an entire large folio, extend set_direct_map APIs
> > to receive number of pages parameter.
> >
> > As there is still only a handful of callers, change the existing
> > functions directly and update all the call sites rather than adding
> > wrappers for single page case.
> >
> > Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
> > ---
> >  arch/arm64/include/asm/set_memory.h     | 4 ++--
> >  arch/arm64/mm/pageattr.c                | 8 ++++----
> >  arch/loongarch/include/asm/set_memory.h | 4 ++--
> >  arch/loongarch/mm/pageattr.c            | 8 ++++----
> >  arch/riscv/include/asm/set_memory.h     | 4 ++--
> >  arch/riscv/mm/pageattr.c                | 8 ++++----
> >  arch/s390/include/asm/set_memory.h      | 4 ++--
> >  arch/s390/mm/pageattr.c                 | 8 ++++----
> >  arch/x86/include/asm/set_memory.h       | 4 ++--
> >  arch/x86/mm/pat/set_memory.c            | 8 ++++----
> >  include/linux/set_memory.h              | 6 ++++--
> >  kernel/power/snapshot.c                 | 4 ++--
> >  mm/secretmem.c                          | 6 +++---
> >  mm/vmalloc.c                            | 5 +++--
> >  14 files changed, 42 insertions(+), 39 deletions(-)
> >
> > diff --git a/arch/arm64/include/asm/set_memory.h b/arch/arm64/include/asm/set_memory.h
> > index 90f61b17275e1..b07fd4e026eac 100644
> > --- a/arch/arm64/include/asm/set_memory.h
> > +++ b/arch/arm64/include/asm/set_memory.h
> > @@ -11,8 +11,8 @@ bool can_set_direct_map(void);
> >  
> >  int set_memory_valid(unsigned long addr, int numpages, int enable);
> >  
> > -int set_direct_map_invalid_noflush(struct page *page);
> > -int set_direct_map_default_noflush(struct page *page);
> > +int set_direct_map_invalid_noflush(struct page *page, unsigned int numpages);
> > +int set_direct_map_default_noflush(struct page *page, unsigned int numpages);
> 
> I don't have a strong opinion on whether to call the argument nr or
> numpages, but we might as well be consistent across archs :)

Well, it's either consistent across archs or consistent within each arch :)
Or add a churny patch that renames it everywhere to nr_pages :)
 
> Aside from that:
> 
> Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>

Thanks!

-- 
Sincerely yours,
Mike.