Re: [RFC][PATCH v3 03/22] mm, x86: add gfp flags variant of pud, pmd, and pte allocations

[Prasad Joshi <prasadjoshi124@gmail.com>]

- Added __pud_alloc_one() function which is similar to pud_alloc_one(), but
  accepts an additional argument of type gfp_t. The function pud_alloc_one()
  calls __pud_alloc_one().

- similar changes for pmd allocations. The newly added function name is__pmd_alloc_one.

- changes for pte allocation. Added function __pte_alloc_one_kernel.

- changes help in fixing the Bug 30702

Signed-off-by: Prasad Joshi <prasadjoshi124@gmail.com>
Signed-off-by: Anand Mitra <mitra@kqinfotech.com>
---
 arch/x86/include/asm/pgalloc.h |   17 +++++++++++++++--
 arch/x86/mm/pgtable.c          |    8 +++++++-
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h
index b4389a4..db83bd4 100644
--- a/arch/x86/include/asm/pgalloc.h
+++ b/arch/x86/include/asm/pgalloc.h
@@ -34,6 +34,7 @@ extern pgd_t *pgd_alloc(struct mm_struct *);
 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
 
 extern pte_t *pte_alloc_one_kernel(struct mm_struct *, unsigned long);
+extern pte_t *__pte_alloc_one_kernel(struct mm_struct *, unsigned long, gfp_t);
 extern pgtable_t pte_alloc_one(struct mm_struct *, unsigned long);
 
 /* Should really implement gc for free page table pages. This could be
@@ -78,9 +79,15 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
 #define pmd_pgtable(pmd) pmd_page(pmd)
 
 #if PAGETABLE_LEVELS > 2
+static inline pmd_t *
+__pmd_alloc_one(struct mm_struct *mm, unsigned long addr, gfp_t gfp_mask)
+{
+	return (pmd_t *)get_zeroed_page(gfp_mask);
+}
+
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	return (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
+	return __pmd_alloc_one(mm, addr, GFP_KERNEL | __GFP_REPEAT);
 }
 
 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
@@ -114,9 +121,15 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 	set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(pud)));
 }
 
+static inline pud_t *
+__pud_alloc_one(struct mm_struct *mm, unsigned long addr, gfp_t gfp_mask)
+{
+	return (pud_t *)get_zeroed_page(gfp_mask);
+}
+
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	return (pud_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
+	return __pud_alloc_one(mm, addr, GFP_KERNEL | __GFP_REPEAT);
 }
 
 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 0113d19..f5205b3 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -15,9 +15,15 @@
 
 gfp_t __userpte_alloc_gfp = PGALLOC_GFP | PGALLOC_USER_GFP;
 
+pte_t *
+__pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address, gfp_t gfp_mask)
+{
+	return (pte_t *)__get_free_page(gfp_mask | __GFP_NOTRACK | __GFP_ZERO);
+}
+
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
-	return (pte_t *)__get_free_page(PGALLOC_GFP);
+	return __pte_alloc_one_kernel(mm, address, GFP_KERNEL | __GFP_REPEAT);
 }
 
 pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
-- 
1.7.0.4