[PATCH v2 16/30] openrisc: Implement the new page table range API

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

Add set_ptes(), update_mmu_cache_range() and flush_dcache_folio().
Change the PG_arch_1 (aka PG_dcache_dirty) flag from being per-page
to per-folio.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: linux-openrisc@vger.kernel.org
---
 arch/openrisc/include/asm/cacheflush.h |  8 +++++++-
 arch/openrisc/include/asm/pgtable.h    | 27 +++++++++++++++++++++-----
 arch/openrisc/mm/cache.c               | 12 ++++++++----
 3 files changed, 37 insertions(+), 10 deletions(-)

diff --git a/arch/openrisc/include/asm/cacheflush.h b/arch/openrisc/include/asm/cacheflush.h
index eeac40d4a854..984c331ff5f4 100644
--- a/arch/openrisc/include/asm/cacheflush.h
+++ b/arch/openrisc/include/asm/cacheflush.h
@@ -56,10 +56,16 @@ static inline void sync_icache_dcache(struct page *page)
  */
 #define PG_dc_clean                  PG_arch_1
 
+static inline void flush_dcache_folio(struct folio *folio)
+{
+	clear_bit(PG_dc_clean, &folio->flags);
+}
+#define flush_dcache_folio flush_dcache_folio
+
 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 static inline void flush_dcache_page(struct page *page)
 {
-	clear_bit(PG_dc_clean, &page->flags);
+	flush_dcache_folio(page_folio(page));
 }
 
 #define flush_icache_user_page(vma, page, addr, len)	\
diff --git a/arch/openrisc/include/asm/pgtable.h b/arch/openrisc/include/asm/pgtable.h
index 3eb9b9555d0d..1a7077150d7b 100644
--- a/arch/openrisc/include/asm/pgtable.h
+++ b/arch/openrisc/include/asm/pgtable.h
@@ -46,7 +46,21 @@ extern void paging_init(void);
  * hook is made available.
  */
 #define set_pte(pteptr, pteval) ((*(pteptr)) = (pteval))
-#define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
+
+static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
+		pte_t *ptep, pte_t pte, unsigned int nr)
+{
+	for (;;) {
+		set_pte(ptep, pte);
+		if (--nr == 0)
+			break;
+		ptep++;
+		pte_val(pte) += PAGE_SIZE;
+	}
+}
+
+#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1)
+
 /*
  * (pmds are folded into pgds so this doesn't get actually called,
  * but the define is needed for a generic inline function.)
@@ -379,13 +393,16 @@ static inline void update_tlb(struct vm_area_struct *vma,
 extern void update_cache(struct vm_area_struct *vma,
 	unsigned long address, pte_t *pte);
 
-static inline void update_mmu_cache(struct vm_area_struct *vma,
-	unsigned long address, pte_t *pte)
+static inline void update_mmu_cache_range(struct vm_area_struct *vma,
+		unsigned long address, pte_t *ptep, unsigned int nr)
 {
-	update_tlb(vma, address, pte);
-	update_cache(vma, address, pte);
+	update_tlb(vma, address, ptep);
+	update_cache(vma, address, ptep);
 }
 
+#define update_mmu_cache(vma, addr, ptep) \
+	update_mmu_cache_range(vma, addr, ptep, 1)
+
 /* __PHX__ FIXME, SWAP, this probably doesn't work */
 
 /*
diff --git a/arch/openrisc/mm/cache.c b/arch/openrisc/mm/cache.c
index 534a52ec5e66..eb43b73f3855 100644
--- a/arch/openrisc/mm/cache.c
+++ b/arch/openrisc/mm/cache.c
@@ -43,15 +43,19 @@ void update_cache(struct vm_area_struct *vma, unsigned long address,
 	pte_t *pte)
 {
 	unsigned long pfn = pte_val(*pte) >> PAGE_SHIFT;
-	struct page *page = pfn_to_page(pfn);
-	int dirty = !test_and_set_bit(PG_dc_clean, &page->flags);
+	struct folio *folio = page_folio(pfn_to_page(pfn));
+	int dirty = !test_and_set_bit(PG_dc_clean, &folio->flags);
 
 	/*
 	 * Since icaches do not snoop for updated data on OpenRISC, we
 	 * must write back and invalidate any dirty pages manually. We
 	 * can skip data pages, since they will not end up in icaches.
 	 */
-	if ((vma->vm_flags & VM_EXEC) && dirty)
-		sync_icache_dcache(page);
+	if ((vma->vm_flags & VM_EXEC) && dirty) {
+		unsigned int nr = folio_nr_pages(folio);
+
+		while (nr--)
+			sync_icache_dcache(folio_page(folio, nr));
+	}
 }
 
-- 
2.39.1