> 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 *addr = kmap_atomic_fast(page);
>
> - preempt_disable();
> - pagefault_disable();
> - if (!PageHighMem(page))
> - return page_address(page);
> + if (addr)
> + return addr;
Wouldn't it make sense to just move kmap_atomic itelf to common code,
and call out to a kmap_atomic_high for the highmem case, following the
scheme in kmap? Same for the unmap side. 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.
