Re: [PATCH 19/31] riscv: use asm-generic/cacheflush.h

Palmer Dabbelt
2020-05-12T23:00:26Z

On Sun, 10 May 2020 00:54:58 PDT (-0700), Christoph Hellwig wrote:
> RISC-V needs almost no cache flushing routines of its own. Rely on
> asm-generic/cacheflush.h for the defaults.
>
> Also remove the pointless __KERNEL__ ifdef while we're at it.
> ---
> arch/riscv/include/asm/cacheflush.h | 62 ++---------------------------
> 1 file changed, 3 insertions(+), 59 deletions(-)
>
> diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h
> index c8677c75f82cb..a167b4fbdf007 100644
> --- a/arch/riscv/include/asm/cacheflush.h
> +++ b/arch/riscv/include/asm/cacheflush.h
> @@ -8,65 +8,6 @@
>
> #include <linux/mm.h>
>
> -#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
> -
> -/*
> - * The cache doesn't need to be flushed when TLB entries change when
> - * the cache is mapped to physical memory, not virtual memory
> - */
> -static inline void flush_cache_all(void)
> -{
> -}
> -
> -static inline void flush_cache_mm(struct mm_struct *mm)
> -{
> -}
> -
> -static inline void flush_cache_dup_mm(struct mm_struct *mm)
> -{
> -}
> -
> -static inline void flush_cache_range(struct vm_area_struct *vma,
> - unsigned long start,
> - unsigned long end)
> -{
> -}
> -
> -static inline void flush_cache_page(struct vm_area_struct *vma,
> - unsigned long vmaddr,
> - unsigned long pfn)
> -{
> -}
> -
> -static inline void flush_dcache_mmap_lock(struct address_space *mapping)
> -{
> -}
> -
> -static inline void flush_dcache_mmap_unlock(struct address_space *mapping)
> -{
> -}
> -
> -static inline void flush_icache_page(struct vm_area_struct *vma,
> - struct page *page)
> -{
> -}
> -
> -static inline void flush_cache_vmap(unsigned long start, unsigned long end)
> -{
> -}
> -
> -static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
> -{
> -}
> -
> -#define copy_to_user_page(vma, page, vaddr, dst, src, len) \
> - do { \
> - memcpy(dst, src, len); \
> - flush_icache_user_range(vma, page, vaddr, len); \
> - } while (0)
> -#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
> - memcpy(dst, src, len)
> -
> static inline void local_flush_icache_all(void)
> {
> asm volatile ("fence.i" ::: "memory");
> @@ -79,6 +20,7 @@ static inline void flush_dcache_page(struct page *page)
> if (test_bit(PG_dcache_clean, &page->flags))
> clear_bit(PG_dcache_clean, &page->flags);
> }
> +#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
>
> /*
> * RISC-V doesn't have an instruction to flush parts of the instruction cache,
> @@ -105,4 +47,6 @@ void flush_icache_mm(struct mm_struct *mm, bool local);
> #define SYS_RISCV_FLUSH_ICACHE_LOCAL 1UL
> #define SYS_RISCV_FLUSH_ICACHE_ALL (SYS_RISCV_FLUSH_ICACHE_LOCAL)
>
> +#include <asm-generic/cacheflush.h>
> +
> #endif /* _ASM_RISCV_CACHEFLUSH_H */

Thanks!

Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>

Were you trying to get these all in at once, or do you want me to take it into
my tree?