[PATCH 3/7] riscv: mm: add Svnapot-aware contiguous PTE wrappers
Yunhui Cui
cuiyunhui at bytedance.com
Tue Apr 21 02:24:53 PDT 2026
Add Svnapot-aware wrappers around the public PTE helpers so core MM
callers can operate on contiguous mappings without learning the NAPOT
encoding details. Introduce contpte.c to handle folding, unfolding and
accessed/dirty state aggregation for contiguous PTE blocks.
Keep the raw __* helpers unchanged so NAPOT-aware callers can continue
to access the underlying PTE encoding directly, and centralize the
public Svnapot-aware wrappers under a single CONFIG_RISCV_ISA_SVNAPOT
block with simple alias fallbacks for the non-Svnapot case.
Signed-off-by: Yunhui Cui <cuiyunhui at bytedance.com>
---
arch/riscv/include/asm/pgtable.h | 288 +++++++++++++++++--
arch/riscv/mm/Makefile | 1 +
arch/riscv/mm/contpte.c | 479 +++++++++++++++++++++++++++++++
arch/riscv/mm/pgtable.c | 39 ++-
4 files changed, 769 insertions(+), 38 deletions(-)
create mode 100644 arch/riscv/mm/contpte.c
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 4de1f40fa77ea..722483d4df37f 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -11,6 +11,10 @@
#include <asm/pgtable-bits.h>
+#ifndef __ASSEMBLER__
+#include <asm/cmpxchg.h>
+#endif
+
#ifndef CONFIG_MMU
#ifdef CONFIG_RELOCATABLE
#define KERNEL_LINK_ADDR UL(0)
@@ -301,6 +305,12 @@ static inline unsigned long pte_napot(pte_t pte)
return 0;
}
+static inline pte_t pte_mknapot(pte_t pte, unsigned int order)
+{
+ (void)order;
+ return pte;
+}
+
#endif /* CONFIG_RISCV_ISA_SVNAPOT */
/* Yields the page frame number (PFN) of a page table entry */
@@ -339,6 +349,11 @@ static inline int pte_present(pte_t pte)
return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
}
+static inline bool pte_present_napot(pte_t pte)
+{
+ return pte_present(pte) && pte_napot(pte);
+}
+
#define pte_accessible pte_accessible
static inline unsigned long pte_accessible(struct mm_struct *mm, pte_t a)
{
@@ -392,6 +407,23 @@ static inline int pte_special(pte_t pte)
return pte_val(pte) & _PAGE_SPECIAL;
}
+static inline pte_t pte_mknonnapot(pte_t pte, unsigned long addr)
+{
+ unsigned long pfn;
+ unsigned long offset;
+ pgprot_t prot;
+
+ if (!pte_present_napot(pte))
+ return pte;
+
+ offset = (addr & (napot_cont_size(napot_cont_order(pte)) - 1)) >>
+ PAGE_SHIFT;
+ pfn = pte_pfn(pte) + offset;
+ prot = __pgprot((pte_val(pte) & ~_PAGE_PFN_MASK) & ~_PAGE_NAPOT);
+
+ return pfn_pte(pfn, prot);
+}
+
/* static inline pte_t pte_rdprotect(pte_t pte) */
static inline pte_t pte_wrprotect(pte_t pte)
@@ -642,24 +674,12 @@ static inline void __set_ptes(struct mm_struct *mm, unsigned long addr,
#define __set_ptes __set_ptes
-static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pteval, unsigned int nr)
-{
- __set_ptes(mm, addr, ptep, pteval, nr);
-}
-
static inline void __pte_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
__set_pte_at(mm, ptep, __pte(0));
}
-static inline void pte_clear(struct mm_struct *mm,
- unsigned long addr, pte_t *ptep)
-{
- __pte_clear(mm, addr, ptep);
-}
-
#define __ptep_get __ptep_get
static inline pte_t __ptep_get(pte_t *ptep)
{
@@ -672,6 +692,47 @@ static inline pte_t __ptep_get_lockless(pte_t *ptep)
return __ptep_get(ptep);
}
+static inline void __clear_young_dirty_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ pte_t pte, cydp_t flags)
+{
+ pte_t old_pte;
+
+ do {
+ old_pte = pte;
+
+ if (flags & CYDP_CLEAR_YOUNG)
+ pte = pte_mkold(pte);
+ if (flags & CYDP_CLEAR_DIRTY)
+ pte = pte_mkclean(pte);
+
+ pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
+ pte_val(old_pte),
+ pte_val(pte));
+ } while (pte_val(pte) != pte_val(old_pte));
+}
+
+static inline void __clear_young_dirty_ptes(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ unsigned int nr, cydp_t flags)
+{
+ pte_t pte;
+
+ for (;;) {
+ pte = __ptep_get(ptep);
+
+ if (flags == (CYDP_CLEAR_YOUNG | CYDP_CLEAR_DIRTY))
+ __set_pte(ptep, pte_mkclean(pte_mkold(pte)));
+ else
+ __clear_young_dirty_pte(vma, addr, ptep, pte, flags);
+
+ if (--nr == 0)
+ break;
+ ptep++;
+ addr += PAGE_SIZE;
+ }
+}
+
#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS /* defined in mm/pgtable.c */
extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
pte_t *ptep, pte_t entry, int dirty);
@@ -703,12 +764,6 @@ __ptep_get_and_clear(struct mm_struct *mm, unsigned long address, pte_t *ptep)
#define __ptep_get_and_clear __ptep_get_and_clear
-static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
- unsigned long address, pte_t *ptep)
-{
- return __ptep_get_and_clear(mm, address, ptep);
-}
-
static inline void
__ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
{
@@ -725,13 +780,6 @@ __ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
#define __ptep_set_wrprotect __ptep_set_wrprotect
-#define __HAVE_ARCH_PTEP_SET_WRPROTECT
-static inline void ptep_set_wrprotect(struct mm_struct *mm,
- unsigned long address, pte_t *ptep)
-{
- __ptep_set_wrprotect(mm, address, ptep);
-}
-
static inline pte_t __ptep_clear_flush(struct vm_area_struct *vma,
unsigned long address,
pte_t *ptep)
@@ -744,9 +792,8 @@ static inline pte_t __ptep_clear_flush(struct vm_area_struct *vma,
return pte;
}
-#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
-static inline bool ptep_clear_flush_young(struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep)
+static inline bool __ptep_clear_flush_young(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep)
{
/*
* This comment is borrowed from x86, but applies equally to RISC-V:
@@ -763,9 +810,192 @@ static inline bool ptep_clear_flush_young(struct vm_area_struct *vma,
* shouldn't really matter because there's no real memory
* pressure for swapout to react to. ]
*/
- return ptep_test_and_clear_young(vma, address, ptep);
+ return __ptep_test_and_clear_young(vma, address, ptep);
+}
+
+#define __ptep_clear_flush_young __ptep_clear_flush_young
+
+#ifdef CONFIG_RISCV_ISA_SVNAPOT
+
+/*
+ * The Svnapot helpers transparently manage napot-encoded PTEs for the public
+ * core-MM-facing API below. The napot bit is a private implementation detail
+ * of those public helpers. Callers that need direct access to the underlying
+ * PTE encoding must use the low-level __* helpers instead.
+ */
+void __napotpte_try_fold(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte);
+void __napotpte_try_unfold(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte);
+pte_t napotpte_ptep_get(pte_t *ptep, pte_t orig_pte);
+pte_t napotpte_ptep_get_lockless(pte_t *ptep);
+void napotpte_set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned int nr);
+void napotpte_clear_young_dirty_ptes(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ unsigned int nr, cydp_t flags);
+bool napotpte_ptep_set_access_flags(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep,
+ pte_t entry, int dirty);
+bool napotpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep);
+bool napotpte_ptep_clear_flush_young(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep);
+
+static __always_inline bool riscv_pte_present_napot(pte_t pte)
+{
+ return riscv_has_extension_unlikely(RISCV_ISA_EXT_SVNAPOT) &&
+ pte_present_napot(pte);
+}
+
+static __always_inline void
+napotpte_try_fold(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
+ pte_t pte)
+{
+ const unsigned long contmask = napot_pte_num(NAPOT_CONT64KB_ORDER) - 1;
+ bool valign = ((addr >> PAGE_SHIFT) & contmask) == contmask;
+
+ if (unlikely(valign)) {
+ bool palign = (pte_pfn(pte) & contmask) == contmask;
+
+ if (unlikely(palign && pte_present(pte) && !pte_napot(pte) &&
+ !pte_special(pte)))
+ __napotpte_try_fold(mm, addr, ptep, pte);
+ }
+}
+
+static __always_inline void
+napotpte_try_unfold(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
+ pte_t pte)
+{
+ if (unlikely(pte_present_napot(pte)))
+ __napotpte_try_unfold(mm, addr, ptep, pte);
+}
+
+#define set_ptes set_ptes
+static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pteval, unsigned int nr)
+{
+ pteval = pte_mknonnapot(pteval, addr);
+
+ if (likely(nr == 1)) {
+ napotpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
+ __set_ptes(mm, addr, ptep, pteval, 1);
+ napotpte_try_fold(mm, addr, ptep, pteval);
+ return;
+ }
+
+ napotpte_set_ptes(mm, addr, ptep, pteval, nr);
+}
+
+static inline void pte_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep)
+{
+ napotpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
+ __pte_clear(mm, addr, ptep);
+}
+
+#define ptep_get ptep_get
+static inline pte_t ptep_get(pte_t *ptep)
+{
+ pte_t pte = __ptep_get(ptep);
+
+ if (likely(!pte_present_napot(pte)))
+ return pte;
+
+ return napotpte_ptep_get(ptep, pte);
+}
+
+#define ptep_get_lockless ptep_get_lockless
+static inline pte_t ptep_get_lockless(pte_t *ptep)
+{
+ pte_t pte = __ptep_get_lockless(ptep);
+
+ if (likely(!pte_present_napot(pte)))
+ return pte;
+
+ return napotpte_ptep_get_lockless(ptep);
+}
+
+static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
+ unsigned long address, pte_t *ptep)
+{
+ napotpte_try_unfold(mm, address, ptep, __ptep_get(ptep));
+
+ return __ptep_get_and_clear(mm, address, ptep);
+}
+
+#define clear_young_dirty_ptes clear_young_dirty_ptes
+static inline void clear_young_dirty_ptes(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ unsigned int nr, cydp_t flags)
+{
+ napotpte_clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
+}
+
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
+static inline void ptep_set_wrprotect(struct mm_struct *mm,
+ unsigned long address, pte_t *ptep)
+{
+ __ptep_set_wrprotect(mm, address, ptep);
}
+#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
+static inline bool ptep_clear_flush_young(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep)
+{
+ pte_t orig_pte = __ptep_get(ptep);
+
+ if (likely(!riscv_pte_present_napot(orig_pte)))
+ return __ptep_clear_flush_young(vma, address, ptep);
+
+ return napotpte_ptep_clear_flush_young(vma, address, ptep);
+}
+
+#else /* CONFIG_RISCV_ISA_SVNAPOT */
+
+static __always_inline bool riscv_pte_present_napot(pte_t pte)
+{
+ return false;
+}
+
+static inline bool napotpte_ptep_set_access_flags(struct vm_area_struct *vma,
+ unsigned long address,
+ pte_t *ptep, pte_t entry,
+ int dirty)
+{
+ return false;
+}
+
+static inline bool
+napotpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long address,
+ pte_t *ptep)
+{
+ return false;
+}
+
+static inline bool
+napotpte_ptep_clear_flush_young(struct vm_area_struct *vma,
+ unsigned long address,
+ pte_t *ptep)
+{
+ return false;
+}
+
+#define set_ptes __set_ptes
+#define pte_clear __pte_clear
+#define ptep_get __ptep_get
+#define ptep_get_lockless __ptep_get_lockless
+#define ptep_get_and_clear __ptep_get_and_clear
+#define clear_young_dirty_ptes __clear_young_dirty_ptes
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
+#define ptep_set_wrprotect __ptep_set_wrprotect
+#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
+#define ptep_clear_flush_young __ptep_clear_flush_young
+
+#endif /* CONFIG_RISCV_ISA_SVNAPOT */
+
#define pgprot_nx pgprot_nx
static inline pgprot_t pgprot_nx(pgprot_t _prot)
{
diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile
index b916a68d324ad..5855f923b83ec 100644
--- a/arch/riscv/mm/Makefile
+++ b/arch/riscv/mm/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_MMU) += extable.o fault.o pageattr.o pgtable.o tlbflush.o
obj-y += cacheflush.o
obj-y += context.o
obj-y += pmem.o
+obj-$(CONFIG_RISCV_ISA_SVNAPOT) += contpte.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_PTDUMP) += ptdump.o
diff --git a/arch/riscv/mm/contpte.c b/arch/riscv/mm/contpte.c
new file mode 100644
index 0000000000000..f73af7d9b099a
--- /dev/null
+++ b/arch/riscv/mm/contpte.c
@@ -0,0 +1,479 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/align.h>
+#include <linux/cpufeature.h>
+#include <linux/efi.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/mm_types.h>
+#include <linux/page_table_check.h>
+#include <linux/pgtable.h>
+
+#include <asm/tlbflush.h>
+
+static inline bool napot_hw_supported(void)
+{
+ return riscv_has_extension_unlikely(RISCV_ISA_EXT_SVNAPOT);
+}
+
+static inline bool mm_is_user(struct mm_struct *mm)
+{
+ if (unlikely(mm_is_efi(mm)))
+ return false;
+
+ return mm != &init_mm;
+}
+
+static inline unsigned int napotpte_order(void)
+{
+ return NAPOT_CONT64KB_ORDER;
+}
+
+static inline unsigned long napotpte_size(void)
+{
+ return napot_cont_size(napotpte_order());
+}
+
+static inline unsigned int napotpte_pte_num(void)
+{
+ return napot_pte_num(napotpte_order());
+}
+
+static inline unsigned long napotpte_mask(void)
+{
+ return napotpte_size() - 1;
+}
+
+static inline unsigned long napot_align_addr(unsigned long addr)
+{
+ return ALIGN_DOWN(addr, napotpte_size());
+}
+
+static inline pte_t *napot_align_ptep(pte_t *ptep)
+{
+ return PTR_ALIGN_DOWN(ptep, napotpte_pte_num() * sizeof(*ptep));
+}
+
+static inline pte_t pte_mask_ad(pte_t pte)
+{
+ return pte_mkold(pte_mkclean(pte));
+}
+
+static inline unsigned long pte_protval_no_pfn_no_napot(pte_t pte)
+{
+ return (pte_val(pte) & ~_PAGE_PFN_MASK) & ~_PAGE_NAPOT;
+}
+
+static inline void napotpte_clear_young_dirty_pte(pte_t *ptep, cydp_t flags)
+{
+ pte_t old_pte, new_pte;
+ unsigned long old_val, new_val;
+
+ do {
+ old_pte = READ_ONCE(*ptep);
+ new_pte = old_pte;
+ if (flags & CYDP_CLEAR_YOUNG)
+ new_pte = pte_mkold(new_pte);
+ if (flags & CYDP_CLEAR_DIRTY)
+ new_pte = pte_mkclean(new_pte);
+
+ old_val = pte_val(old_pte);
+ new_val = pte_val(new_pte);
+ } while (cmpxchg_relaxed(&pte_val(*ptep), old_val, new_val) != old_val);
+}
+
+static inline pte_t napotpte_subpte(pte_t *ptep, pte_t pte)
+{
+ unsigned long pfn;
+ pgprot_t prot;
+
+ if (!pte_present_napot(pte))
+ return pte;
+
+ pfn = pte_pfn(pte) + (ptep - napot_align_ptep(ptep));
+ prot = __pgprot(pte_protval_no_pfn_no_napot(pte));
+
+ return pfn_pte(pfn, prot);
+}
+
+static inline pte_t
+__napot_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
+{
+ pte_t pte;
+
+ pte = __pte(atomic_long_xchg((atomic_long_t *)ptep, 0));
+ page_table_check_pte_clear(mm, addr, pte);
+
+ return pte;
+}
+
+static void napotpte_convert(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t target)
+{
+ unsigned long start_addr, end;
+ pte_t *start_ptep;
+ pte_t ptent, pte;
+ unsigned int i, nr;
+
+ start_addr = napot_align_addr(addr);
+ start_ptep = napot_align_ptep(ptep);
+ nr = napotpte_pte_num();
+ end = start_addr + napotpte_size();
+
+ for (i = 0; i < nr; i++) {
+ ptent = __napot_ptep_get_and_clear(mm, start_addr + i * PAGE_SIZE,
+ start_ptep + i);
+ if (pte_dirty(ptent))
+ target = pte_mkdirty(target);
+ if (pte_young(ptent))
+ target = pte_mkyoung(target);
+ }
+
+ flush_tlb_mm_range(mm, start_addr, end, PAGE_SIZE);
+
+ page_table_check_ptes_set(mm, start_addr, start_ptep, target, nr);
+ if (pte_napot(target)) {
+ for (i = 0; i < nr; i++)
+ __set_pte_at(mm, start_ptep + i, target);
+ return;
+ }
+
+ for (i = 0; i < nr; i++) {
+ pte = pfn_pte(pte_pfn(target) + i,
+ __pgprot(pte_protval_no_pfn_no_napot(target)));
+ if (pte_dirty(target))
+ pte = pte_mkdirty(pte);
+ if (pte_young(target))
+ pte = pte_mkyoung(pte);
+ __set_pte_at(mm, start_ptep + i, pte);
+ }
+}
+
+static inline bool napotpte_is_consistent(pte_t pte, pte_t orig_pte)
+{
+ return pte_present_napot(pte) &&
+ pte_val(pte_mask_ad(pte)) == pte_val(pte_mask_ad(orig_pte));
+}
+
+void __napotpte_try_fold(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ struct page *page;
+ struct folio *folio;
+ unsigned long folio_start, folio_end;
+ unsigned long cont_start, cont_end;
+ unsigned long pfn;
+ pgprot_t prot;
+ pte_t expected, cur;
+ pte_t *start;
+ unsigned int i, nr;
+
+ if (!napot_hw_supported() || !mm_is_user(mm))
+ return;
+
+ if (!pte_present(pte) || pte_napot(pte) || pte_special(pte))
+ return;
+
+ page = pte_page(pte);
+ folio = page_folio(page);
+ folio_start = addr - (page - &folio->page) * PAGE_SIZE;
+ folio_end = folio_start + folio_nr_pages(folio) * PAGE_SIZE;
+ cont_start = napot_align_addr(addr);
+ cont_end = cont_start + napotpte_size();
+ if (folio_start > cont_start || folio_end < cont_end)
+ return;
+
+ nr = napotpte_pte_num();
+ start = napot_align_ptep(ptep);
+
+ pfn = ALIGN_DOWN(pte_pfn(pte), nr);
+ prot = pte_pgprot(pte_mask_ad(pte));
+ expected = pfn_pte(pfn, prot);
+
+ for (i = 0; i < nr; i++) {
+ cur = READ_ONCE(start[i]);
+ if (pte_val(pte_mask_ad(cur)) != pte_val(expected))
+ return;
+ pte_val(expected) += 1UL << _PAGE_PFN_SHIFT;
+ }
+
+ expected = pte_mknapot(pfn_pte(pfn, prot), napotpte_order());
+ napotpte_convert(mm, addr, ptep, expected);
+}
+EXPORT_SYMBOL(__napotpte_try_fold);
+
+void __napotpte_try_unfold(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ pte_t target;
+ pgprot_t prot;
+
+ if (!napot_hw_supported() || !mm_is_user(mm))
+ return;
+
+ prot = __pgprot(pte_protval_no_pfn_no_napot(pte));
+ target = pfn_pte(pte_pfn(pte), prot);
+
+ napotpte_convert(mm, addr, ptep, target);
+}
+EXPORT_SYMBOL(__napotpte_try_unfold);
+
+pte_t napotpte_ptep_get(pte_t *ptep, pte_t orig_pte)
+{
+ pte_t pte, cur;
+ pte_t *start;
+ unsigned int i, nr;
+
+ if (!napot_hw_supported() || !pte_present_napot(orig_pte))
+ return orig_pte;
+
+ pte = orig_pte;
+ start = napot_align_ptep(ptep);
+ nr = napotpte_pte_num();
+
+ for (i = 0; i < nr; i++) {
+ cur = READ_ONCE(start[i]);
+ if (!napotpte_is_consistent(cur, orig_pte))
+ return napotpte_subpte(ptep, orig_pte);
+ if (pte_dirty(cur))
+ pte = pte_mkdirty(pte);
+ if (pte_young(cur))
+ pte = pte_mkyoung(pte);
+ }
+
+ return napotpte_subpte(ptep, pte);
+}
+EXPORT_SYMBOL(napotpte_ptep_get);
+
+pte_t napotpte_ptep_get_lockless(pte_t *orig_ptep)
+{
+ pte_t orig_pte, pte;
+ pte_t *ptep;
+ unsigned int i, nr;
+
+ if (!napot_hw_supported())
+ return READ_ONCE(*orig_ptep);
+
+ nr = napotpte_pte_num();
+
+retry:
+ orig_pte = READ_ONCE(*orig_ptep);
+ if (!pte_present_napot(orig_pte))
+ return orig_pte;
+
+ ptep = napot_align_ptep(orig_ptep);
+
+ for (i = 0; i < nr; i++, ptep++) {
+ pte = READ_ONCE(*ptep);
+
+ if (!napotpte_is_consistent(pte, orig_pte))
+ goto retry;
+
+ if (pte_dirty(pte)) {
+ orig_pte = pte_mkdirty(orig_pte);
+ for (; i < nr; i++, ptep++) {
+ pte = READ_ONCE(*ptep);
+
+ if (!napotpte_is_consistent(pte, orig_pte))
+ goto retry;
+
+ if (pte_young(pte)) {
+ orig_pte = pte_mkyoung(orig_pte);
+ break;
+ }
+ }
+ break;
+ }
+
+ if (pte_young(pte)) {
+ orig_pte = pte_mkyoung(orig_pte);
+ i++;
+ ptep++;
+ for (; i < nr; i++, ptep++) {
+ pte = READ_ONCE(*ptep);
+
+ if (!napotpte_is_consistent(pte, orig_pte))
+ goto retry;
+
+ if (pte_dirty(pte)) {
+ orig_pte = pte_mkdirty(orig_pte);
+ break;
+ }
+ }
+ break;
+ }
+ }
+
+ return napotpte_subpte(orig_ptep, orig_pte);
+}
+EXPORT_SYMBOL(napotpte_ptep_get_lockless);
+
+void napotpte_set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned int nr)
+{
+ unsigned long next, end;
+ unsigned long pfn, size, boundary;
+ pgprot_t prot;
+ unsigned int chunk, i;
+ pte_t cur;
+
+ if (!napot_hw_supported() || !mm_is_user(mm)) {
+ __set_ptes(mm, addr, ptep, pte, nr);
+ return;
+ }
+
+ size = napotpte_size();
+ end = addr + ((unsigned long)nr << PAGE_SHIFT);
+ pfn = pte_pfn(pte);
+ prot = __pgprot(pte_protval_no_pfn_no_napot(pte));
+
+ do {
+ boundary = (addr + size) & ~napotpte_mask();
+ next = (boundary - 1 < end - 1) ? boundary : end;
+ chunk = (next - addr) >> PAGE_SHIFT;
+
+ cur = pfn_pte(pfn, prot);
+ if (((addr | next | (pfn << PAGE_SHIFT)) & napotpte_mask()) == 0) {
+ cur = pte_mknapot(cur, napotpte_order());
+ page_table_check_ptes_set(mm, addr, ptep, cur, chunk);
+ for (i = 0; i < chunk; i++)
+ __set_pte_at(mm, ptep + i, cur);
+ } else {
+ __set_ptes(mm, addr, ptep, cur, chunk);
+ }
+
+ addr = next;
+ ptep += chunk;
+ pfn += chunk;
+ } while (addr != end);
+}
+EXPORT_SYMBOL(napotpte_set_ptes);
+
+void napotpte_clear_young_dirty_ptes(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ unsigned int nr, cydp_t flags)
+{
+ struct mm_struct *mm;
+ unsigned long start, end;
+ unsigned int total;
+
+ mm = vma->vm_mm;
+ if (!napot_hw_supported() || !mm_is_user(mm)) {
+ for (;;) {
+ if (flags == CYDP_CLEAR_YOUNG)
+ __ptep_test_and_clear_young(vma, addr, ptep);
+ else
+ napotpte_clear_young_dirty_pte(ptep, flags);
+ if (--nr == 0)
+ break;
+ ptep++;
+ addr += PAGE_SIZE;
+ }
+ return;
+ }
+
+ start = addr;
+ end = start + nr * PAGE_SIZE;
+
+ if (pte_present_napot(READ_ONCE(*(ptep + nr - 1))))
+ end = ALIGN(end, napotpte_size());
+
+ if (pte_present_napot(READ_ONCE(*ptep))) {
+ start = napot_align_addr(start);
+ ptep = napot_align_ptep(ptep);
+ }
+
+ total = (end - start) >> PAGE_SHIFT;
+ for (; total; total--, ptep++, start += PAGE_SIZE)
+ napotpte_clear_young_dirty_pte(ptep, flags);
+}
+EXPORT_SYMBOL(napotpte_clear_young_dirty_ptes);
+
+bool napotpte_ptep_set_access_flags(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep,
+ pte_t entry, int dirty)
+{
+ pte_t orig_pte, raw_pte, napot_pte;
+ pte_t *start;
+ pgprot_t prot;
+ unsigned long start_addr;
+ unsigned int i, nr;
+ bool changed;
+
+ raw_pte = READ_ONCE(*ptep);
+ if (!napot_hw_supported() || !pte_present_napot(raw_pte))
+ return false;
+
+ orig_pte = ptep_get(ptep);
+ if (pte_val(orig_pte) == pte_val(entry))
+ return false;
+
+ if (pte_write(orig_pte) != pte_write(entry)) {
+ __napotpte_try_unfold(vma->vm_mm, address, ptep, raw_pte);
+ entry = pte_mknonnapot(entry, address);
+
+ return ptep_set_access_flags(vma, address, ptep, entry, dirty);
+ }
+
+ prot = pte_pgprot(entry);
+ napot_pte = pfn_pte(pte_pfn(raw_pte), prot);
+ napot_pte = pte_mknapot(napot_pte, napotpte_order());
+
+ start = napot_align_ptep(ptep);
+ start_addr = napot_align_addr(address);
+ nr = napotpte_pte_num();
+ changed = false;
+
+ page_table_check_ptes_set(vma->vm_mm, start_addr, start, napot_pte, nr);
+ for (i = 0; i < nr; i++) {
+ if (!pte_same(READ_ONCE(start[i]), napot_pte)) {
+ __set_pte_at(vma->vm_mm, start + i, napot_pte);
+ changed = true;
+ }
+ }
+
+ if (changed)
+ flush_tlb_range(vma, start_addr, start_addr + napotpte_size());
+
+ return changed;
+}
+EXPORT_SYMBOL(napotpte_ptep_set_access_flags);
+
+bool napotpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep)
+{
+ pte_t *start;
+ unsigned int i, nr;
+ bool young;
+
+ if (!napot_hw_supported() || !pte_present_napot(READ_ONCE(*ptep)))
+ return false;
+
+ start = napot_align_ptep(ptep);
+ nr = napotpte_pte_num();
+ young = false;
+
+ for (i = 0; i < nr; i++)
+ young |= test_and_clear_bit(_PAGE_ACCESSED_OFFSET,
+ &pte_val(start[i]));
+
+ return young;
+}
+EXPORT_SYMBOL(napotpte_ptep_test_and_clear_young);
+
+bool napotpte_ptep_clear_flush_young(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep)
+{
+ unsigned long start_addr;
+ bool young;
+
+ young = napotpte_ptep_test_and_clear_young(vma, address, ptep);
+ if (!young)
+ return false;
+
+ start_addr = napot_align_addr(address);
+ flush_tlb_range(vma, start_addr, start_addr + napotpte_size());
+
+ return true;
+}
+EXPORT_SYMBOL(napotpte_ptep_clear_flush_young);
diff --git a/arch/riscv/mm/pgtable.c b/arch/riscv/mm/pgtable.c
index 9131a78fe15c4..85ff49286f91c 100644
--- a/arch/riscv/mm/pgtable.c
+++ b/arch/riscv/mm/pgtable.c
@@ -9,6 +9,14 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep,
pte_t entry, int dirty)
{
+ pte_t raw_pte;
+
+ entry = pte_mknonnapot(entry, address);
+ raw_pte = READ_ONCE(*ptep);
+ if (riscv_pte_present_napot(raw_pte))
+ return napotpte_ptep_set_access_flags(vma, address, ptep, entry,
+ dirty);
+
return __ptep_set_access_flags(vma, address, ptep, entry, dirty);
}
@@ -16,19 +24,26 @@ int __ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep,
pte_t entry, int dirty)
{
- if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SVVPTC)) {
- if (!pte_same(ptep_get(ptep), entry)) {
- __set_pte_at(vma->vm_mm, ptep, entry);
- /* Here only not svadu is impacted */
- flush_tlb_page(vma, address);
- return true;
- }
+ pte_t raw_pte;
+ bool changed;
+
+ entry = pte_mknonnapot(entry, address);
+ raw_pte = READ_ONCE(*ptep);
+ if (riscv_pte_present_napot(raw_pte))
+ return false;
+ changed = !pte_same(raw_pte, entry);
+ if (!changed)
return false;
+
+ __set_pte_at(vma->vm_mm, ptep, entry);
+
+ if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SVVPTC)) {
+ /* Here only not svadu is impacted */
+ flush_tlb_page(vma, address);
+ return true;
}
- if (!pte_same(ptep_get(ptep), entry))
- __set_pte_at(vma->vm_mm, ptep, entry);
/*
* update_mmu_cache will unconditionally execute, handling both
* the case that the PTE changed and the spurious fault case.
@@ -39,6 +54,12 @@ int __ptep_set_access_flags(struct vm_area_struct *vma,
bool ptep_test_and_clear_young(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep)
{
+ pte_t raw_pte;
+
+ raw_pte = READ_ONCE(*ptep);
+ if (riscv_pte_present_napot(raw_pte))
+ return napotpte_ptep_test_and_clear_young(vma, address, ptep);
+
return __ptep_test_and_clear_young(vma, address, ptep);
}
EXPORT_SYMBOL_GPL(ptep_test_and_clear_young);
--
2.39.5
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