[PATCH v2] mm/hugetlb: add more arch-defined huge_pte functions

From: Gerald Schaefer
Date: Thu Mar 14 2013 - 13:51:29 EST


Commit abf09bed3c "s390/mm: implement software dirty bits" introduced
another difference in the pte layout vs. the pmd layout on s390,
thoroughly breaking the s390 support for hugetlbfs. This requires
replacing some more pte_xxx functions in mm/hugetlbfs.c with a
huge_pte_xxx version.

This patch introduces those huge_pte_xxx functions and their
generic implementation in asm-generic/hugetlb.h, which will now be
included on all architectures supporting hugetlbfs apart from s390.
This change will be a no-op for those architectures.

Signed-off-by: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx>
---
arch/ia64/include/asm/hugetlb.h | 1 +
arch/mips/include/asm/hugetlb.h | 1 +
arch/powerpc/include/asm/hugetlb.h | 1 +
arch/s390/include/asm/hugetlb.h | 56 +++++++++++++++++++++-
arch/s390/include/asm/pgtable.h | 95 ++++++++++++++++----------------------
arch/s390/mm/hugetlbpage.c | 2 +-
arch/sh/include/asm/hugetlb.h | 1 +
arch/sparc/include/asm/hugetlb.h | 1 +
arch/tile/include/asm/hugetlb.h | 1 +
arch/x86/include/asm/hugetlb.h | 1 +
include/asm-generic/hugetlb.h | 40 ++++++++++++++++
mm/hugetlb.c | 23 ++++-----
12 files changed, 155 insertions(+), 68 deletions(-)
create mode 100644 include/asm-generic/hugetlb.h

diff --git a/arch/ia64/include/asm/hugetlb.h b/arch/ia64/include/asm/hugetlb.h
index 94eaa5b..aa91005 100644
--- a/arch/ia64/include/asm/hugetlb.h
+++ b/arch/ia64/include/asm/hugetlb.h
@@ -2,6 +2,7 @@
#define _ASM_IA64_HUGETLB_H

#include <asm/page.h>
+#include <asm-generic/hugetlb.h>


void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h
index ef99db9..fe0d15d 100644
--- a/arch/mips/include/asm/hugetlb.h
+++ b/arch/mips/include/asm/hugetlb.h
@@ -10,6 +10,7 @@
#define __ASM_HUGETLB_H

#include <asm/page.h>
+#include <asm-generic/hugetlb.h>


static inline int is_hugepage_only_range(struct mm_struct *mm,
diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h
index 62e11a3..4fcbd6b 100644
--- a/arch/powerpc/include/asm/hugetlb.h
+++ b/arch/powerpc/include/asm/hugetlb.h
@@ -3,6 +3,7 @@

#ifdef CONFIG_HUGETLB_PAGE
#include <asm/page.h>
+#include <asm-generic/hugetlb.h>

extern struct kmem_cache *hugepte_cache;

diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 593753e..bd90359 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -114,7 +114,7 @@ static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
#define huge_ptep_set_wrprotect(__mm, __addr, __ptep) \
({ \
pte_t __pte = huge_ptep_get(__ptep); \
- if (pte_write(__pte)) { \
+ if (huge_pte_write(__pte)) { \
huge_ptep_invalidate(__mm, __addr, __ptep); \
set_huge_pte_at(__mm, __addr, __ptep, \
huge_pte_wrprotect(__pte)); \
@@ -127,4 +127,58 @@ static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
huge_ptep_invalidate(vma->vm_mm, address, ptep);
}

+static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
+{
+ pte_t pte;
+ pmd_t pmd;
+
+ pmd = mk_pmd_phys(page_to_phys(page), pgprot);
+ pte_val(pte) = pmd_val(pmd);
+ return pte;
+}
+
+static inline int huge_pte_write(pte_t pte)
+{
+ pmd_t pmd;
+
+ pmd_val(pmd) = pte_val(pte);
+ return pmd_write(pmd);
+}
+
+static inline int huge_pte_dirty(pte_t pte)
+{
+ /* No dirty bit in the segment table entry. */
+ return 0;
+}
+
+static inline pte_t huge_pte_mkwrite(pte_t pte)
+{
+ pmd_t pmd;
+
+ pmd_val(pmd) = pte_val(pte);
+ pte_val(pte) = pmd_val(pmd_mkwrite(pmd));
+ return pte;
+}
+
+static inline pte_t huge_pte_mkdirty(pte_t pte)
+{
+ /* No dirty bit in the segment table entry. */
+ return pte;
+}
+
+static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
+{
+ pmd_t pmd;
+
+ pmd_val(pmd) = pte_val(pte);
+ pte_val(pte) = pmd_val(pmd_modify(pmd, newprot));
+ return pte;
+}
+
+static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ pmd_clear((pmd_t *) ptep);
+}
+
#endif /* _ASM_S390_HUGETLB_H */
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 75b8750..7c9a145 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -419,6 +419,13 @@ extern unsigned long MODULES_END;
#define __S110 PAGE_RW
#define __S111 PAGE_RW

+/*
+ * Segment entry (large page) protection definitions.
+ */
+#define SEGMENT_NONE __pgprot(_HPAGE_TYPE_NONE)
+#define SEGMENT_RO __pgprot(_HPAGE_TYPE_RO)
+#define SEGMENT_RW __pgprot(_HPAGE_TYPE_RW)
+
static inline int mm_exclusive(struct mm_struct *mm)
{
return likely(mm == current->active_mm &&
@@ -909,26 +916,6 @@ static inline pte_t pte_mkspecial(pte_t pte)
#ifdef CONFIG_HUGETLB_PAGE
static inline pte_t pte_mkhuge(pte_t pte)
{
- /*
- * PROT_NONE needs to be remapped from the pte type to the ste type.
- * The HW invalid bit is also different for pte and ste. The pte
- * invalid bit happens to be the same as the ste _SEGMENT_ENTRY_LARGE
- * bit, so we don't have to clear it.
- */
- if (pte_val(pte) & _PAGE_INVALID) {
- if (pte_val(pte) & _PAGE_SWT)
- pte_val(pte) |= _HPAGE_TYPE_NONE;
- pte_val(pte) |= _SEGMENT_ENTRY_INV;
- }
- /*
- * Clear SW pte bits, there are no SW bits in a segment table entry.
- */
- pte_val(pte) &= ~(_PAGE_SWT | _PAGE_SWX | _PAGE_SWC |
- _PAGE_SWR | _PAGE_SWW);
- /*
- * Also set the change-override bit because we don't need dirty bit
- * tracking for hugetlbfs pages.
- */
pte_val(pte) |= (_SEGMENT_ENTRY_LARGE | _SEGMENT_ENTRY_CO);
return pte;
}
@@ -1273,31 +1260,7 @@ static inline void __pmd_idte(unsigned long address, pmd_t *pmdp)
}
}

-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-
-#define SEGMENT_NONE __pgprot(_HPAGE_TYPE_NONE)
-#define SEGMENT_RO __pgprot(_HPAGE_TYPE_RO)
-#define SEGMENT_RW __pgprot(_HPAGE_TYPE_RW)
-
-#define __HAVE_ARCH_PGTABLE_DEPOSIT
-extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pgtable_t pgtable);
-
-#define __HAVE_ARCH_PGTABLE_WITHDRAW
-extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm);
-
-static inline int pmd_trans_splitting(pmd_t pmd)
-{
- return pmd_val(pmd) & _SEGMENT_ENTRY_SPLIT;
-}
-
-static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
- pmd_t *pmdp, pmd_t entry)
-{
- if (!(pmd_val(entry) & _SEGMENT_ENTRY_INV) && MACHINE_HAS_EDAT1)
- pmd_val(entry) |= _SEGMENT_ENTRY_CO;
- *pmdp = entry;
-}
-
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
static inline unsigned long massage_pgprot_pmd(pgprot_t pgprot)
{
/*
@@ -1318,10 +1281,11 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
return pmd;
}

-static inline pmd_t pmd_mkhuge(pmd_t pmd)
+static inline pmd_t mk_pmd_phys(unsigned long physpage, pgprot_t pgprot)
{
- pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
- return pmd;
+ pmd_t __pmd;
+ pmd_val(__pmd) = physpage + massage_pgprot_pmd(pgprot);
+ return __pmd;
}

static inline pmd_t pmd_mkwrite(pmd_t pmd)
@@ -1331,6 +1295,34 @@ static inline pmd_t pmd_mkwrite(pmd_t pmd)
pmd_val(pmd) &= ~_SEGMENT_ENTRY_RO;
return pmd;
}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLB_PAGE */
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+
+#define __HAVE_ARCH_PGTABLE_DEPOSIT
+extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pgtable_t pgtable);
+
+#define __HAVE_ARCH_PGTABLE_WITHDRAW
+extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm);
+
+static inline int pmd_trans_splitting(pmd_t pmd)
+{
+ return pmd_val(pmd) & _SEGMENT_ENTRY_SPLIT;
+}
+
+static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
+ pmd_t *pmdp, pmd_t entry)
+{
+ if (!(pmd_val(entry) & _SEGMENT_ENTRY_INV) && MACHINE_HAS_EDAT1)
+ pmd_val(entry) |= _SEGMENT_ENTRY_CO;
+ *pmdp = entry;
+}
+
+static inline pmd_t pmd_mkhuge(pmd_t pmd)
+{
+ pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
+ return pmd;
+}

static inline pmd_t pmd_wrprotect(pmd_t pmd)
{
@@ -1427,13 +1419,6 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
}
}

-static inline pmd_t mk_pmd_phys(unsigned long physpage, pgprot_t pgprot)
-{
- pmd_t __pmd;
- pmd_val(__pmd) = physpage + massage_pgprot_pmd(pgprot);
- return __pmd;
-}
-
#define pfn_pmd(pfn, pgprot) mk_pmd_phys(__pa((pfn) << PAGE_SHIFT), (pgprot))
#define mk_pmd(page, pgprot) pfn_pmd(page_to_pfn(page), (pgprot))

diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index 532525e..121089d 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -39,7 +39,7 @@ int arch_prepare_hugepage(struct page *page)
if (!ptep)
return -ENOMEM;

- pte = mk_pte(page, PAGE_RW);
+ pte_val(pte) = addr;
for (i = 0; i < PTRS_PER_PTE; i++) {
set_pte_at(&init_mm, addr + i * PAGE_SIZE, ptep + i, pte);
pte_val(pte) += PAGE_SIZE;
diff --git a/arch/sh/include/asm/hugetlb.h b/arch/sh/include/asm/hugetlb.h
index b3808c7..699255d 100644
--- a/arch/sh/include/asm/hugetlb.h
+++ b/arch/sh/include/asm/hugetlb.h
@@ -3,6 +3,7 @@

#include <asm/cacheflush.h>
#include <asm/page.h>
+#include <asm-generic/hugetlb.h>


static inline int is_hugepage_only_range(struct mm_struct *mm,
diff --git a/arch/sparc/include/asm/hugetlb.h b/arch/sparc/include/asm/hugetlb.h
index 7eb57d2..e4cab46 100644
--- a/arch/sparc/include/asm/hugetlb.h
+++ b/arch/sparc/include/asm/hugetlb.h
@@ -2,6 +2,7 @@
#define _ASM_SPARC64_HUGETLB_H

#include <asm/page.h>
+#include <asm-generic/hugetlb.h>


void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
diff --git a/arch/tile/include/asm/hugetlb.h b/arch/tile/include/asm/hugetlb.h
index 0f885af..3257733 100644
--- a/arch/tile/include/asm/hugetlb.h
+++ b/arch/tile/include/asm/hugetlb.h
@@ -16,6 +16,7 @@
#define _ASM_TILE_HUGETLB_H

#include <asm/page.h>
+#include <asm-generic/hugetlb.h>


static inline int is_hugepage_only_range(struct mm_struct *mm,
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index bdd35db..a809121 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -2,6 +2,7 @@
#define _ASM_X86_HUGETLB_H

#include <asm/page.h>
+#include <asm-generic/hugetlb.h>


static inline int is_hugepage_only_range(struct mm_struct *mm,
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
new file mode 100644
index 0000000..d06079c
--- /dev/null
+++ b/include/asm-generic/hugetlb.h
@@ -0,0 +1,40 @@
+#ifndef _ASM_GENERIC_HUGETLB_H
+#define _ASM_GENERIC_HUGETLB_H
+
+static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
+{
+ return mk_pte(page, pgprot);
+}
+
+static inline int huge_pte_write(pte_t pte)
+{
+ return pte_write(pte);
+}
+
+static inline int huge_pte_dirty(pte_t pte)
+{
+ return pte_dirty(pte);
+}
+
+static inline pte_t huge_pte_mkwrite(pte_t pte)
+{
+ return pte_mkwrite(pte);
+}
+
+static inline pte_t huge_pte_mkdirty(pte_t pte)
+{
+ return pte_mkdirty(pte);
+}
+
+static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
+{
+ return pte_modify(pte, newprot);
+}
+
+static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ pte_clear(mm, addr, ptep);
+}
+
+#endif /* _ASM_GENERIC_HUGETLB_H */
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index c65a8a5..43425ad 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2243,10 +2243,11 @@ static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
pte_t entry;

if (writable) {
- entry =
- pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
+ entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page,
+ vma->vm_page_prot)));
} else {
- entry = huge_pte_wrprotect(mk_pte(page, vma->vm_page_prot));
+ entry = huge_pte_wrprotect(mk_huge_pte(page,
+ vma->vm_page_prot));
}
entry = pte_mkyoung(entry);
entry = pte_mkhuge(entry);
@@ -2260,7 +2261,7 @@ static void set_huge_ptep_writable(struct vm_area_struct *vma,
{
pte_t entry;

- entry = pte_mkwrite(pte_mkdirty(huge_ptep_get(ptep)));
+ entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep)));
if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1))
update_mmu_cache(vma, address, ptep);
}
@@ -2375,7 +2376,7 @@ again:
* HWPoisoned hugepage is already unmapped and dropped reference
*/
if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) {
- pte_clear(mm, address, ptep);
+ huge_pte_clear(mm, address, ptep);
continue;
}

@@ -2399,7 +2400,7 @@ again:

pte = huge_ptep_get_and_clear(mm, address, ptep);
tlb_remove_tlb_entry(tlb, ptep, address);
- if (pte_dirty(pte))
+ if (huge_pte_dirty(pte))
set_page_dirty(page);

page_remove_rmap(page);
@@ -2852,7 +2853,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
* page now as it is used to determine if a reservation has been
* consumed.
*/
- if ((flags & FAULT_FLAG_WRITE) && !pte_write(entry)) {
+ if ((flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) {
if (vma_needs_reservation(h, vma, address) < 0) {
ret = VM_FAULT_OOM;
goto out_mutex;
@@ -2882,12 +2883,12 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,


if (flags & FAULT_FLAG_WRITE) {
- if (!pte_write(entry)) {
+ if (!huge_pte_write(entry)) {
ret = hugetlb_cow(mm, vma, address, ptep, entry,
pagecache_page);
goto out_page_table_lock;
}
- entry = pte_mkdirty(entry);
+ entry = huge_pte_mkdirty(entry);
}
entry = pte_mkyoung(entry);
if (huge_ptep_set_access_flags(vma, address, ptep, entry,
@@ -2958,7 +2959,7 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
}

if (absent ||
- ((flags & FOLL_WRITE) && !pte_write(huge_ptep_get(pte)))) {
+ ((flags & FOLL_WRITE) && !huge_pte_write(huge_ptep_get(pte)))) {
int ret;

spin_unlock(&mm->page_table_lock);
@@ -3028,7 +3029,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
}
if (!huge_pte_none(huge_ptep_get(ptep))) {
pte = huge_ptep_get_and_clear(mm, address, ptep);
- pte = pte_mkhuge(pte_modify(pte, newprot));
+ pte = pte_mkhuge(huge_pte_modify(pte, newprot));
pte = arch_make_huge_pte(pte, vma, NULL, 0);
set_huge_pte_at(mm, address, ptep, pte);
pages++;
--
1.7.12.4

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