Much of the required code for THP has been implemented in the earlier non-LPAE
HugeTLB patch.
One more domain bits is used (to store whether or not the THP is splitting).
Some THP helper functions are defined; and we have to re-define pmd_page such
that it distinguishes between page tables and sections.
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Steve Capper <steve.capper@xxxxxxx>
---
arch/arm/Kconfig | 2 +-
arch/arm/include/asm/pgtable-2level.h | 68 ++++++++++++++++++++++++++++++++-
arch/arm/include/asm/pgtable-3level.h | 2 +
arch/arm/include/asm/pgtable.h | 7 +++-
4 files changed, 75 insertions(+), 4 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 9621d5f..d459673 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1773,7 +1773,7 @@ config SYS_SUPPORTS_HUGETLBFS
config HAVE_ARCH_TRANSPARENT_HUGEPAGE
def_bool y
- depends on ARM_LPAE
+ depends on SYS_SUPPORTS_HUGETLBFS
source "mm/Kconfig"
diff --git a/arch/arm/include/asm/pgtable-2level.h b/arch/arm/include/asm/pgtable-2level.h
index 34f4775..67eabb4 100644
--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h
@@ -179,6 +179,13 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
clean_pmd_entry(pmdp); \
} while (0)
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#define _PMD_HUGE(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_SECT)
+#else
+#define _PMD_HUGE(pmd) (0)
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
/* we don't need complex calculations here as the pmd is folded into the pgd */
#define pmd_addr_end(addr,end) (end)
@@ -197,7 +204,6 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
#define HPAGE_SHIFT PMD_SHIFT
#define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT)
-#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
#define HUGE_LINUX_PTE_COUNT (PAGE_OFFSET >> HPAGE_SHIFT)
@@ -209,6 +215,7 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
*/
#define PMD_DSECT_DIRTY (_AT(pmdval_t, 1) << 5)
#define PMD_DSECT_AF (_AT(pmdval_t, 1) << 6)
+#define PMD_DSECT_SPLITTING (_AT(pmdval_t, 1) << 7)
#define PMD_BIT_FUNC(fn,op) \
static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; }
@@ -261,8 +268,67 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
return __pmd(pmdval);
}
+#else
+#define HPAGE_SIZE 0
#endif /* CONFIG_SYS_SUPPORTS_HUGETLBFS */
+#define HPAGE_MASK (~(HPAGE_SIZE - 1))
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#define pmd_mkhuge(pmd) (__pmd((pmd_val(pmd) & ~PMD_TYPE_MASK) | PMD_TYPE_SECT))
+
+PMD_BIT_FUNC(mkold, &= ~PMD_DSECT_AF);
+PMD_BIT_FUNC(mksplitting, |= PMD_DSECT_SPLITTING);
+PMD_BIT_FUNC(mkdirty, |= PMD_DSECT_DIRTY);
+PMD_BIT_FUNC(mkyoung, |= PMD_DSECT_AF);
+PMD_BIT_FUNC(mkwrite, |= PMD_SECT_AP_WRITE);
+PMD_BIT_FUNC(mknotpresent, &= ~PMD_TYPE_MASK);
+
+#define pmd_trans_splitting(pmd) (pmd_val(pmd) & PMD_DSECT_SPLITTING)
+#define pmd_young(pmd) (pmd_val(pmd) & PMD_DSECT_AF)
+#define pmd_write(pmd) (pmd_val(pmd) & PMD_SECT_AP_WRITE)
+#define pmd_trans_huge(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_SECT)
+
+static inline unsigned long pmd_pfn(pmd_t pmd)
+{
+ /*
+ * for a section, we need to mask off more of the pmd
+ * before looking up the pfn
+ */
+ if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_SECT)
+ return __phys_to_pfn(pmd_val(pmd) & HPAGE_MASK);
+ else
+ return __phys_to_pfn(pmd_val(pmd) & PHYS_MASK);
+}
+
+static inline pmd_t pfn_pmd(unsigned long pfn, pgprot_t prot)
+{
+ pmd_t pmd = __pmd(__pfn_to_phys(pfn) | PMD_SECT_AP_READ | PMD_SECT_nG);
+
+ return pmd_modify(pmd, prot);
+}
+
+#define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot);
+
+static inline int has_transparent_hugepage(void)
+{
+ return 1;
+}
+
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
+static inline struct page *pmd_page(pmd_t pmd)
+{
+ /*
+ * for a section, we need to mask off more of the pmd
+ * before looking up the page as it is a section descriptor.
+ */
+ if (_PMD_HUGE(pmd))
+ return phys_to_page(pmd_val(pmd) & HPAGE_MASK);
+
+ return phys_to_page(pmd_val(pmd) & PHYS_MASK);
+}
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_PGTABLE_2LEVEL_H */
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 31c071f..8360814 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -197,6 +197,8 @@ PMD_BIT_FUNC(mknotpresent, &= ~PMD_TYPE_MASK);
#define pfn_pmd(pfn,prot) (__pmd(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
#define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot)
+#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
+
static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
{
const pmdval_t mask = PMD_SECT_USER | PMD_SECT_XN | PMD_SECT_RDONLY;
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 767aa7c..2d96381 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -169,11 +169,14 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
static inline pte_t *pmd_page_vaddr(pmd_t pmd)
{
+#ifdef SYS_SUPPORTS_HUGETLBFS
+ if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_SECT)
+ return __va(pmd_val(pmd) & HPAGE_MASK);
+#endif
+
return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
}
-#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
-
#ifndef CONFIG_HIGHPTE
#define __pte_map(pmd) pmd_page_vaddr(*(pmd))
#define __pte_unmap(pte) do { } while (0)
--
1.7.9.5
--
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