On Sun, Apr 26, 2020 at 06:16:30PM -0700, Ira Weiny wrote:
> > That might require to support
> > kmap_atomic_prot everywhere first, which sounds like a really good
> > idea anyway, and would avoid the need for strange workaround in drm.
>
> Having a kmap_atomic_prot() seems like a good idea. But
On Sun, Apr 26, 2020 at 12:26:42AM -0700, Christoph Hellwig wrote:
> > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
> > index 4db13a6b9f3b..1cae4b911a33 100644
> > --- a/arch/arc/mm/highmem.c
> > +++ b/arch/arc/mm/highmem.c
> > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page)
> diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
> index 4db13a6b9f3b..1cae4b911a33 100644
> --- a/arch/arc/mm/highmem.c
> +++ b/arch/arc/mm/highmem.c
> @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page)
> {
> int idx, cpu_idx;
> unsigned long vaddr;
> + void *add
From: Ira Weiny
Every arch has the same check for a not HIGHMEM page. Define
kmap_atomic_fast() to quickly return already mapped pages and reduce the
code duplication by lifting this check to the core.
Reviewed-by: Dan Williams
Signed-off-by: Ira Weiny
---
arch/arc/mm/highmem.c| 7 ++
