[PATCH RESEND v2 4/9] mm: Use common set_huge_pte_at() function for riscv/arm64
Alexandre Ghiti
alexghiti at rivosinc.com
Wed May 8 04:34:14 PDT 2024
After some adjustments, both architectures have the same implementation
so move it to generic code.
Signed-off-by: Alexandre Ghiti <alexghiti at rivosinc.com>
---
arch/arm64/include/asm/pgtable.h | 14 +++++---
arch/arm64/mm/hugetlbpage.c | 56 -----------------------------
arch/riscv/include/asm/pgtable.h | 39 +++++++++++++-------
arch/riscv/mm/hugetlbpage.c | 62 --------------------------------
mm/contpte.c | 59 ++++++++++++++++++++++++++++++
5 files changed, 95 insertions(+), 135 deletions(-)
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index e30149a128f2..2e0415fd5083 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -372,9 +372,10 @@ static inline pte_t pte_advance_pfn(pte_t pte, unsigned long nr)
return pfn_pte(pte_pfn(pte) + nr, pte_pgprot(pte));
}
-static inline void __set_ptes(struct mm_struct *mm,
- unsigned long __always_unused addr,
- pte_t *ptep, pte_t pte, unsigned int nr)
+static inline void ___set_ptes(struct mm_struct *mm,
+ unsigned long __always_unused addr,
+ pte_t *ptep, pte_t pte, unsigned int nr,
+ size_t pgsize)
{
page_table_check_ptes_set(mm, ptep, pte, nr);
__sync_cache_and_tags(pte, nr);
@@ -385,10 +386,15 @@ static inline void __set_ptes(struct mm_struct *mm,
if (--nr == 0)
break;
ptep++;
- pte = pte_advance_pfn(pte, 1);
+ pte = pte_advance_pfn(pte, pgsize >> PAGE_SHIFT);
}
}
+#define __set_ptes(mm, addr, ptep, pte, nr) \
+ ___set_ptes(mm, addr, ptep, pte, nr, PAGE_SIZE)
+
+#define set_contptes ___set_ptes
+
/*
* Huge pte definitions.
*/
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 9e9c80ec6e74..b8353b0a273c 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -159,62 +159,6 @@ static pte_t get_clear_contig_flush(struct mm_struct *mm,
return orig_pte;
}
-/*
- * Changing some bits of contiguous entries requires us to follow a
- * Break-Before-Make approach, breaking the whole contiguous set
- * before we can change any entries. See ARM DDI 0487A.k_iss10775,
- * "Misprogramming of the Contiguous bit", page D4-1762.
- *
- * This helper performs the break step for use cases where the
- * original pte is not needed.
- */
-static void clear_flush(struct mm_struct *mm,
- unsigned long addr,
- pte_t *ptep,
- unsigned long pgsize,
- unsigned long ncontig)
-{
- struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0);
- unsigned long i, saddr = addr;
-
- for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
- __ptep_get_and_clear(mm, addr, ptep);
-
- flush_tlb_range(&vma, saddr, addr);
-}
-
-void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte, unsigned long sz)
-{
- size_t pgsize;
- int i;
- int ncontig;
- unsigned long pfn, dpfn;
- pgprot_t hugeprot;
-
- ncontig = arch_contpte_get_num_contig(ptep, sz, &pgsize);
-
- if (!pte_present(pte)) {
- for (i = 0; i < ncontig; i++, ptep++, addr += pgsize)
- __set_ptes(mm, addr, ptep, pte, 1);
- return;
- }
-
- if (!pte_cont(pte)) {
- __set_ptes(mm, addr, ptep, pte, 1);
- return;
- }
-
- pfn = pte_pfn(pte);
- dpfn = pgsize >> PAGE_SHIFT;
- hugeprot = pte_pgprot(pte);
-
- clear_flush(mm, addr, ptep, pgsize, ncontig);
-
- for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
- __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1);
-}
-
pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, unsigned long sz)
{
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 66061002ff36..5d1d3a6c7c44 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -535,29 +535,39 @@ static inline void __set_pte_at(struct mm_struct *mm, pte_t *ptep, pte_t pteval)
static inline int arch_contpte_get_num_contig(pte_t *ptep, unsigned long size,
size_t *pgsize)
{
+ unsigned long hugepage_shift;
pte_t __pte;
/* We must read the raw value of the pte to get the size of the mapping */
__pte = READ_ONCE(*ptep);
- if (pgsize) {
- if (size >= PGDIR_SIZE)
+ if (size >= PGDIR_SIZE) {
+ if (pgsize)
*pgsize = PGDIR_SIZE;
- else if (size >= P4D_SIZE)
+ hugepage_shift = PGDIR_SHIFT;
+ } else if (size >= P4D_SIZE) {
+ if (pgsize)
*pgsize = P4D_SIZE;
- else if (size >= PUD_SIZE)
+ hugepage_shift = P4D_SHIFT;
+ } else if (size >= PUD_SIZE) {
+ if (pgsize)
*pgsize = PUD_SIZE;
- else if (size >= PMD_SIZE)
+ hugepage_shift = PUD_SHIFT;
+ } else if (size >= PMD_SIZE) {
+ if (pgsize)
*pgsize = PMD_SIZE;
- else
+ hugepage_shift = PMD_SHIFT;
+ } else {
+ if (pgsize)
*pgsize = PAGE_SIZE;
+ hugepage_shift = PAGE_SHIFT;
}
/* Make sure __pte is not a swap entry */
if (pte_valid_napot(__pte))
return napot_pte_num(napot_cont_order(__pte));
- return 1;
+ return size >> hugepage_shift;
}
#endif
@@ -586,8 +596,8 @@ static inline pte_t __ptep_get(pte_t *ptep)
return pte;
}
-static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pteval, unsigned int nr)
+static inline void __set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pteval, unsigned int nr)
{
#ifdef CONFIG_RISCV_ISA_SVNAPOT
if (unlikely(pte_valid_napot(pteval))) {
@@ -631,7 +641,8 @@ static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
pte_val(pteval) += 1 << _PAGE_PFN_SHIFT;
}
}
-#define set_ptes set_ptes
+#define set_contptes(mm, addr, ptep, pte, nr, pgsize) \
+ __set_ptes(mm, addr, ptep, pte, nr)
static inline void pte_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
@@ -646,9 +657,8 @@ extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addre
extern int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long address,
pte_t *ptep);
-#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
-static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
- unsigned long address, pte_t *ptep)
+static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
+ unsigned long address, pte_t *ptep)
{
pte_t pte = __pte(atomic_long_xchg((atomic_long_t *)ptep, 0));
@@ -687,6 +697,9 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
}
#define ptep_get __ptep_get
+#define set_ptes __set_ptes
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
+#define ptep_get_and_clear __ptep_get_and_clear
#define pgprot_nx pgprot_nx
static inline pgprot_t pgprot_nx(pgprot_t _prot)
diff --git a/arch/riscv/mm/hugetlbpage.c b/arch/riscv/mm/hugetlbpage.c
index be129f4f1503..d8f07aef758b 100644
--- a/arch/riscv/mm/hugetlbpage.c
+++ b/arch/riscv/mm/hugetlbpage.c
@@ -173,68 +173,6 @@ pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags)
return entry;
}
-static void clear_flush(struct mm_struct *mm,
- unsigned long addr,
- pte_t *ptep,
- unsigned long pgsize,
- unsigned long ncontig)
-{
- struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0);
- unsigned long i, saddr = addr;
-
- for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
- ptep_get_and_clear(mm, addr, ptep);
-
- flush_tlb_range(&vma, saddr, addr);
-}
-
-/*
- * When dealing with NAPOT mappings, the privileged specification indicates that
- * "if an update needs to be made, the OS generally should first mark all of the
- * PTEs invalid, then issue SFENCE.VMA instruction(s) covering all 4 KiB regions
- * within the range, [...] then update the PTE(s), as described in Section
- * 4.2.1.". That's the equivalent of the Break-Before-Make approach used by
- * arm64.
- */
-void set_huge_pte_at(struct mm_struct *mm,
- unsigned long addr,
- pte_t *ptep,
- pte_t pte,
- unsigned long sz)
-{
- unsigned long hugepage_shift, pgsize;
- int i, pte_num;
-
- if (sz >= PGDIR_SIZE)
- hugepage_shift = PGDIR_SHIFT;
- else if (sz >= P4D_SIZE)
- hugepage_shift = P4D_SHIFT;
- else if (sz >= PUD_SIZE)
- hugepage_shift = PUD_SHIFT;
- else if (sz >= PMD_SIZE)
- hugepage_shift = PMD_SHIFT;
- else
- hugepage_shift = PAGE_SHIFT;
-
- pte_num = sz >> hugepage_shift;
- pgsize = 1 << hugepage_shift;
-
- if (!pte_present(pte)) {
- for (i = 0; i < pte_num; i++, ptep++, addr += pgsize)
- set_ptes(mm, addr, ptep, pte, 1);
- return;
- }
-
- if (!pte_napot(pte)) {
- set_ptes(mm, addr, ptep, pte, 1);
- return;
- }
-
- clear_flush(mm, addr, ptep, pgsize, pte_num);
-
- set_ptes(mm, addr, ptep, pte, pte_num);
-}
-
int huge_ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long addr,
pte_t *ptep,
diff --git a/mm/contpte.c b/mm/contpte.c
index e8574051d0b9..2320ee23478a 100644
--- a/mm/contpte.c
+++ b/mm/contpte.c
@@ -10,6 +10,8 @@
/*
* Any arch that wants to use that needs to define:
* - __ptep_get()
+ * - __set_ptes()
+ * - __ptep_get_and_clear()
* - pte_cont()
* - arch_contpte_get_num_contig()
*/
@@ -17,6 +19,7 @@
/*
* This file implements the following contpte aware API:
* - huge_ptep_get()
+ * - set_huge_pte_at()
*/
pte_t huge_ptep_get(pte_t *ptep)
@@ -43,3 +46,59 @@ pte_t huge_ptep_get(pte_t *ptep)
}
return orig_pte;
}
+
+/*
+ * ARM64: Changing some bits of contiguous entries requires us to follow a
+ * Break-Before-Make approach, breaking the whole contiguous set
+ * before we can change any entries. See ARM DDI 0487A.k_iss10775,
+ * "Misprogramming of the Contiguous bit", page D4-1762.
+ *
+ * RISCV: When dealing with NAPOT mappings, the privileged specification
+ * indicates that "if an update needs to be made, the OS generally should first
+ * mark all of the PTEs invalid, then issue SFENCE.VMA instruction(s) covering
+ * all 4 KiB regions within the range, [...] then update the PTE(s), as
+ * described in Section 4.2.1.". That's the equivalent of the Break-Before-Make
+ * approach used by arm64.
+ *
+ * This helper performs the break step for use cases where the
+ * original pte is not needed.
+ */
+static void clear_flush(struct mm_struct *mm,
+ unsigned long addr,
+ pte_t *ptep,
+ unsigned long pgsize,
+ unsigned long ncontig)
+{
+ struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0);
+ unsigned long i, saddr = addr;
+
+ for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
+ __ptep_get_and_clear(mm, addr, ptep);
+
+ flush_tlb_range(&vma, saddr, addr);
+}
+
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned long sz)
+{
+ size_t pgsize;
+ int i;
+ int ncontig;
+
+ ncontig = arch_contpte_get_num_contig(ptep, sz, &pgsize);
+
+ if (!pte_present(pte)) {
+ for (i = 0; i < ncontig; i++, ptep++, addr += pgsize)
+ __set_ptes(mm, addr, ptep, pte, 1);
+ return;
+ }
+
+ if (!pte_cont(pte)) {
+ __set_ptes(mm, addr, ptep, pte, 1);
+ return;
+ }
+
+ clear_flush(mm, addr, ptep, pgsize, ncontig);
+
+ set_contptes(mm, addr, ptep, pte, ncontig, pgsize);
+}
--
2.39.2
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