[PATCH v4 28/36] xtensa: Implement the new page table range API

From: Matthew Wilcox (Oracle)
Date: Wed Mar 15 2023 - 01:16:05 EST


Add PFN_PTE_SHIFT, update_mmu_cache_range(), flush_dcache_folio() and
flush_icache_pages().

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Max Filippov <jcmvbkbc@xxxxxxxxx>
Cc: linux-xtensa@xxxxxxxxxxxxxxxx
---
arch/xtensa/include/asm/cacheflush.h | 9 ++-
arch/xtensa/include/asm/pgtable.h | 17 +++---
arch/xtensa/mm/cache.c | 83 ++++++++++++++++------------
3 files changed, 62 insertions(+), 47 deletions(-)

diff --git a/arch/xtensa/include/asm/cacheflush.h b/arch/xtensa/include/asm/cacheflush.h
index 7b4359312c25..35153f6725e4 100644
--- a/arch/xtensa/include/asm/cacheflush.h
+++ b/arch/xtensa/include/asm/cacheflush.h
@@ -119,8 +119,14 @@ void flush_cache_page(struct vm_area_struct*,
#define flush_cache_vmap(start,end) flush_cache_all()
#define flush_cache_vunmap(start,end) flush_cache_all()

+void flush_dcache_folio(struct folio *folio);
+#define flush_dcache_folio flush_dcache_folio
+
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
-void flush_dcache_page(struct page *);
+static inline void flush_dcache_page(struct page *page)
+{
+ flush_dcache_folio(page_folio(page));
+}

void local_flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end);
@@ -156,6 +162,7 @@ void local_flush_cache_page(struct vm_area_struct *vma,

/* This is not required, see Documentation/core-api/cachetlb.rst */
#define flush_icache_page(vma,page) do { } while (0)
+#define flush_icache_pages(vma, page, nr) do { } while (0)

#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index fc7a14884c6c..80bc70251aad 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -274,6 +274,7 @@ static inline pte_t pte_mkwrite(pte_t pte)
* and a page entry and page directory to the page they refer to.
*/

+#define PFN_PTE_SHIFT PAGE_SHIFT
#define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT)
#define pte_same(a,b) (pte_val(a) == pte_val(b))
#define pte_page(x) pfn_to_page(pte_pfn(x))
@@ -301,15 +302,9 @@ static inline void update_pte(pte_t *ptep, pte_t pteval)

struct mm_struct;

-static inline void
-set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pteval)
-{
- update_pte(ptep, pteval);
-}
-
-static inline void set_pte(pte_t *ptep, pte_t pteval)
+static inline void set_pte(pte_t *ptep, pte_t pte)
{
- update_pte(ptep, pteval);
+ update_pte(ptep, pte);
}

static inline void
@@ -407,8 +402,10 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)

#else

-extern void update_mmu_cache(struct vm_area_struct * vma,
- unsigned long address, pte_t *ptep);
+void update_mmu_cache_range(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep, unsigned int nr);
+#define update_mmu_cache(vma, address, ptep) \
+ update_mmu_cache_range(vma, address, ptep, 1)

typedef pte_t *pte_addr_t;

diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c
index 19e5a478a7e8..27bd798e4d89 100644
--- a/arch/xtensa/mm/cache.c
+++ b/arch/xtensa/mm/cache.c
@@ -121,9 +121,9 @@ EXPORT_SYMBOL(copy_user_highpage);
*
*/

-void flush_dcache_page(struct page *page)
+void flush_dcache_folio(struct folio *folio)
{
- struct address_space *mapping = page_mapping_file(page);
+ struct address_space *mapping = folio_flush_mapping(folio);

/*
* If we have a mapping but the page is not mapped to user-space
@@ -132,14 +132,14 @@ void flush_dcache_page(struct page *page)
*/

if (mapping && !mapping_mapped(mapping)) {
- if (!test_bit(PG_arch_1, &page->flags))
- set_bit(PG_arch_1, &page->flags);
+ if (!test_bit(PG_arch_1, &folio->flags))
+ set_bit(PG_arch_1, &folio->flags);
return;

} else {
-
- unsigned long phys = page_to_phys(page);
- unsigned long temp = page->index << PAGE_SHIFT;
+ unsigned long phys = folio_pfn(folio) * PAGE_SIZE;
+ unsigned long temp = folio_pos(folio);
+ unsigned int i, nr = folio_nr_pages(folio);
unsigned long alias = !(DCACHE_ALIAS_EQ(temp, phys));
unsigned long virt;

@@ -154,22 +154,26 @@ void flush_dcache_page(struct page *page)
return;

preempt_disable();
- virt = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK);
- __flush_invalidate_dcache_page_alias(virt, phys);
+ for (i = 0; i < nr; i++) {
+ virt = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(virt, phys);

- virt = TLBTEMP_BASE_1 + (temp & DCACHE_ALIAS_MASK);
+ virt = TLBTEMP_BASE_1 + (temp & DCACHE_ALIAS_MASK);

- if (alias)
- __flush_invalidate_dcache_page_alias(virt, phys);
+ if (alias)
+ __flush_invalidate_dcache_page_alias(virt, phys);

- if (mapping)
- __invalidate_icache_page_alias(virt, phys);
+ if (mapping)
+ __invalidate_icache_page_alias(virt, phys);
+ phys += PAGE_SIZE;
+ temp += PAGE_SIZE;
+ }
preempt_enable();
}

/* There shouldn't be an entry in the cache for this page anymore. */
}
-EXPORT_SYMBOL(flush_dcache_page);
+EXPORT_SYMBOL(flush_dcache_folio);

/*
* For now, flush the whole cache. FIXME??
@@ -207,45 +211,52 @@ EXPORT_SYMBOL(local_flush_cache_page);

#endif /* DCACHE_WAY_SIZE > PAGE_SIZE */

-void
-update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t *ptep)
+void update_mmu_cache_range(struct vm_area_struct *vma, unsigned long addr,
+ pte_t *ptep, unsigned int nr)
{
unsigned long pfn = pte_pfn(*ptep);
- struct page *page;
+ struct folio *folio;
+ unsigned int i;

if (!pfn_valid(pfn))
return;

- page = pfn_to_page(pfn);
+ folio = page_folio(pfn_to_page(pfn));

- /* Invalidate old entry in TLBs */
-
- flush_tlb_page(vma, addr);
+ /* Invalidate old entries in TLBs */
+ for (i = 0; i < nr; i++)
+ flush_tlb_page(vma, addr + i * PAGE_SIZE);
+ nr = folio_nr_pages(folio);

#if (DCACHE_WAY_SIZE > PAGE_SIZE)

- if (!PageReserved(page) && test_bit(PG_arch_1, &page->flags)) {
- unsigned long phys = page_to_phys(page);
+ if (!folio_test_reserved(folio) && test_bit(PG_arch_1, &folio->flags)) {
+ unsigned long phys = folio_pfn(folio) * PAGE_SIZE;
unsigned long tmp;

preempt_disable();
- tmp = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK);
- __flush_invalidate_dcache_page_alias(tmp, phys);
- tmp = TLBTEMP_BASE_1 + (addr & DCACHE_ALIAS_MASK);
- __flush_invalidate_dcache_page_alias(tmp, phys);
- __invalidate_icache_page_alias(tmp, phys);
+ for (i = 0; i < nr; i++) {
+ tmp = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(tmp, phys);
+ tmp = TLBTEMP_BASE_1 + (addr & DCACHE_ALIAS_MASK);
+ __flush_invalidate_dcache_page_alias(tmp, phys);
+ __invalidate_icache_page_alias(tmp, phys);
+ phys += PAGE_SIZE;
+ }
preempt_enable();

- clear_bit(PG_arch_1, &page->flags);
+ clear_bit(PG_arch_1, &folio->flags);
}
#else
- if (!PageReserved(page) && !test_bit(PG_arch_1, &page->flags)
+ if (!folio_test_reserved(folio) && !test_bit(PG_arch_1, &folio->flags)
&& (vma->vm_flags & VM_EXEC) != 0) {
- unsigned long paddr = (unsigned long)kmap_atomic(page);
- __flush_dcache_page(paddr);
- __invalidate_icache_page(paddr);
- set_bit(PG_arch_1, &page->flags);
- kunmap_atomic((void *)paddr);
+ for (i = 0; i < nr; i++) {
+ void *paddr = kmap_local_folio(folio, i * PAGE_SIZE);
+ __flush_dcache_page((unsigned long)paddr);
+ __invalidate_icache_page((unsigned long)paddr);
+ kunmap_local(paddr);
+ }
+ set_bit(PG_arch_1, &folio->flags);
}
#endif
}
--
2.39.2