Re: [PATCH v4 12/36] ia64: Implement the new page table range API
From: Mike Rapoport
Date: Wed Mar 15 2023 - 05:57:32 EST
On Wed, Mar 15, 2023 at 05:14:20AM +0000, Matthew Wilcox (Oracle) wrote:
> Add PFN_PTE_SHIFT, update_mmu_cache_range() and flush_dcache_folio().
> Change the PG_arch_1 (aka PG_dcache_clean) flag from being per-page to
> per-folio, which makes arch_dma_mark_clean() and mark_clean() a little
> more exciting.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Cc: linux-ia64@xxxxxxxxxxxxxxx
Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
> ---
> arch/ia64/hp/common/sba_iommu.c | 26 +++++++++++++++-----------
> arch/ia64/include/asm/cacheflush.h | 14 ++++++++++----
> arch/ia64/include/asm/pgtable.h | 4 ++--
> arch/ia64/mm/init.c | 28 +++++++++++++++++++---------
> 4 files changed, 46 insertions(+), 26 deletions(-)
>
> diff --git a/arch/ia64/hp/common/sba_iommu.c b/arch/ia64/hp/common/sba_iommu.c
> index 8ad6946521d8..48d475f10003 100644
> --- a/arch/ia64/hp/common/sba_iommu.c
> +++ b/arch/ia64/hp/common/sba_iommu.c
> @@ -798,22 +798,26 @@ sba_io_pdir_entry(u64 *pdir_ptr, unsigned long vba)
> #endif
>
> #ifdef ENABLE_MARK_CLEAN
> -/**
> +/*
> * Since DMA is i-cache coherent, any (complete) pages that were written via
> * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
> * flush them when they get mapped into an executable vm-area.
> */
> -static void
> -mark_clean (void *addr, size_t size)
> +static void mark_clean(void *addr, size_t size)
> {
> - unsigned long pg_addr, end;
> -
> - pg_addr = PAGE_ALIGN((unsigned long) addr);
> - end = (unsigned long) addr + size;
> - while (pg_addr + PAGE_SIZE <= end) {
> - struct page *page = virt_to_page((void *)pg_addr);
> - set_bit(PG_arch_1, &page->flags);
> - pg_addr += PAGE_SIZE;
> + struct folio *folio = virt_to_folio(addr);
> + ssize_t left = size;
> + size_t offset = offset_in_folio(folio, addr);
> +
> + if (offset) {
> + left -= folio_size(folio) - offset;
> + folio = folio_next(folio);
> + }
> +
> + while (left >= folio_size(folio)) {
> + set_bit(PG_arch_1, &folio->flags);
> + left -= folio_size(folio);
> + folio = folio_next(folio);
> }
> }
> #endif
> diff --git a/arch/ia64/include/asm/cacheflush.h b/arch/ia64/include/asm/cacheflush.h
> index 708c0fa5d975..eac493fa9e0d 100644
> --- a/arch/ia64/include/asm/cacheflush.h
> +++ b/arch/ia64/include/asm/cacheflush.h
> @@ -13,10 +13,16 @@
> #include <asm/page.h>
>
> #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
> -#define flush_dcache_page(page) \
> -do { \
> - clear_bit(PG_arch_1, &(page)->flags); \
> -} while (0)
> +static inline void flush_dcache_folio(struct folio *folio)
> +{
> + clear_bit(PG_arch_1, &folio->flags);
> +}
> +#define flush_dcache_folio flush_dcache_folio
> +
> +static inline void flush_dcache_page(struct page *page)
> +{
> + flush_dcache_folio(page_folio(page));
> +}
>
> extern void flush_icache_range(unsigned long start, unsigned long end);
> #define flush_icache_range flush_icache_range
> diff --git a/arch/ia64/include/asm/pgtable.h b/arch/ia64/include/asm/pgtable.h
> index 21c97e31a28a..5450d59e4fb9 100644
> --- a/arch/ia64/include/asm/pgtable.h
> +++ b/arch/ia64/include/asm/pgtable.h
> @@ -206,6 +206,7 @@ ia64_phys_addr_valid (unsigned long addr)
> #define RGN_MAP_SHIFT (PGDIR_SHIFT + PTRS_PER_PGD_SHIFT - 3)
> #define RGN_MAP_LIMIT ((1UL << RGN_MAP_SHIFT) - PAGE_SIZE) /* per region addr limit */
>
> +#define PFN_PTE_SHIFT PAGE_SHIFT
> /*
> * Conversion functions: convert page frame number (pfn) and a protection value to a page
> * table entry (pte).
> @@ -303,8 +304,6 @@ static inline void set_pte(pte_t *ptep, pte_t pteval)
> *ptep = pteval;
> }
>
> -#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
> -
> /*
> * Make page protection values cacheable, uncacheable, or write-
> * combining. Note that "protection" is really a misnomer here as the
> @@ -396,6 +395,7 @@ pte_same (pte_t a, pte_t b)
> return pte_val(a) == pte_val(b);
> }
>
> +#define update_mmu_cache_range(vma, address, ptep, nr) do { } while (0)
> #define update_mmu_cache(vma, address, ptep) do { } while (0)
>
> extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
> diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
> index 7f5353e28516..b95debabdc2a 100644
> --- a/arch/ia64/mm/init.c
> +++ b/arch/ia64/mm/init.c
> @@ -50,30 +50,40 @@ void
> __ia64_sync_icache_dcache (pte_t pte)
> {
> unsigned long addr;
> - struct page *page;
> + struct folio *folio;
>
> - page = pte_page(pte);
> - addr = (unsigned long) page_address(page);
> + folio = page_folio(pte_page(pte));
> + addr = (unsigned long)folio_address(folio);
>
> - if (test_bit(PG_arch_1, &page->flags))
> + if (test_bit(PG_arch_1, &folio->flags))
> return; /* i-cache is already coherent with d-cache */
>
> - flush_icache_range(addr, addr + page_size(page));
> - set_bit(PG_arch_1, &page->flags); /* mark page as clean */
> + flush_icache_range(addr, addr + folio_size(folio));
> + set_bit(PG_arch_1, &folio->flags); /* mark page as clean */
> }
>
> /*
> - * Since DMA is i-cache coherent, any (complete) pages that were written via
> + * Since DMA is i-cache coherent, any (complete) folios that were written via
> * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
> * flush them when they get mapped into an executable vm-area.
> */
> void arch_dma_mark_clean(phys_addr_t paddr, size_t size)
> {
> unsigned long pfn = PHYS_PFN(paddr);
> + struct folio *folio = page_folio(pfn_to_page(pfn));
> + ssize_t left = size;
> + size_t offset = offset_in_folio(folio, paddr);
>
> - do {
> + if (offset) {
> + left -= folio_size(folio) - offset;
> + folio = folio_next(folio);
> + }
> +
> + while (left >= (ssize_t)folio_size(folio)) {
> set_bit(PG_arch_1, &pfn_to_page(pfn)->flags);
> - } while (++pfn <= PHYS_PFN(paddr + size - 1));
> + left -= folio_size(folio);
> + folio = folio_next(folio);
> + }
> }
>
> inline void
> --
> 2.39.2
>
>
--
Sincerely yours,
Mike.