Several place need to find the pmd by(mm_struct, address), so introduce a
function to simple it.
Signed-off-by: Bob Liu <lliubbo@xxxxxxxxx>
---
mm/huge_memory.c | 55 ++++++++++--------------------------------------------
mm/internal.h | 5 +++++
mm/ksm.c | 14 ++------------
mm/migrate.c | 14 ++------------
mm/rmap.c | 46 ++++++++++++++++++++++++---------------------
5 files changed, 44 insertions(+), 90 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 96a2ccc..dcf5642 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1145,22 +1145,14 @@ pmd_t *page_check_address_pmd(struct page *page,
unsigned long address,
enum page_check_address_pmd_flag flag)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd, *ret = NULL;
if (address & ~HPAGE_PMD_MASK)
goto out;
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
+ pmd = mm_find_pmd(mm, address);
+ if (!pmd)
goto out;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- goto out;
-
- pmd = pmd_offset(pud, address);
if (pmd_none(*pmd))
goto out;
if (pmd_page(*pmd) != page)
@@ -1907,8 +1899,6 @@ static void collapse_huge_page(struct mm_struct *mm,
struct vm_area_struct *vma,
int node)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd, _pmd;
pte_t *pte;
pgtable_t pgtable;
@@ -1954,17 +1944,10 @@ static void collapse_huge_page(struct mm_struct *mm,
goto out;
VM_BUG_ON(vma->vm_flags & VM_NO_THP);
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
+ pmd = mm_find_pmd(mm, address);
+ if (!pmd)
goto out;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- goto out;
-
- pmd = pmd_offset(pud, address);
- /* pmd can't go away or become huge under us */
- if (!pmd_present(*pmd) || pmd_trans_huge(*pmd))
+ if (pmd_trans_huge(*pmd))
goto out;
anon_vma_lock(vma->anon_vma);
@@ -2047,8 +2030,6 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
unsigned long address,
struct page **hpage)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
pte_t *pte, *_pte;
int ret = 0, referenced = 0, none = 0;
@@ -2059,16 +2040,10 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
+ pmd = mm_find_pmd(mm, address);
+ if (!pmd)
goto out;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- goto out;
-
- pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd) || pmd_trans_huge(*pmd))
+ if (pmd_trans_huge(*pmd))
goto out;
pte = pte_offset_map_lock(mm, pmd, address, &ptl);
@@ -2362,22 +2337,12 @@ void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd)
static void split_huge_page_address(struct mm_struct *mm,
unsigned long address)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
VM_BUG_ON(!(address & ~HPAGE_PMD_MASK));
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- return;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- return;
-
- pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd))
+ pmd = mm_find_pmd(mm, address);
+ if (!pmd)
return;
/*
* Caller holds the mmap_sem write mode, so a huge pmd cannot
diff --git a/mm/internal.h b/mm/internal.h
index a4fa284..52d1fa9 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -92,6 +92,11 @@ extern int isolate_lru_page(struct page *page);
extern void putback_lru_page(struct page *page);
/*
+ * in mm/rmap.c:
+ */
+extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);
+
+/*
* in mm/page_alloc.c
*/
extern void __free_pages_bootmem(struct page *page, unsigned int order);
diff --git a/mm/ksm.c b/mm/ksm.c
index ae539f0..31ae5ea 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -778,8 +778,6 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
struct page *kpage, pte_t orig_pte)
{
struct mm_struct *mm = vma->vm_mm;
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
pte_t *ptep;
spinlock_t *ptl;
@@ -792,18 +790,10 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
if (addr == -EFAULT)
goto out;
- pgd = pgd_offset(mm, addr);
- if (!pgd_present(*pgd))
+ pmd = mm_find_pmd(mm, addr);
+ if (!pmd)
goto out;
-
- pud = pud_offset(pgd, addr);
- if (!pud_present(*pud))
- goto out;
-
- pmd = pmd_offset(pud, addr);
BUG_ON(pmd_trans_huge(*pmd));
- if (!pmd_present(*pmd))
- goto out;
mmun_start = addr;
mmun_end = addr + PAGE_SIZE;
diff --git a/mm/migrate.c b/mm/migrate.c
index 77ed2d7..1dc4598 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -91,8 +91,6 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma,
{
struct mm_struct *mm = vma->vm_mm;
swp_entry_t entry;
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
pte_t *ptep, pte;
spinlock_t *ptl;
@@ -103,19 +101,11 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma,
goto out;
ptl = &mm->page_table_lock;
} else {
- pgd = pgd_offset(mm, addr);
- if (!pgd_present(*pgd))
+ pmd = mm_find_pmd(mm, addr);
+ if (!pmd)
goto out;
-
- pud = pud_offset(pgd, addr);
- if (!pud_present(*pud))
- goto out;
-
- pmd = pmd_offset(pud, addr);
if (pmd_trans_huge(*pmd))
goto out;
- if (!pmd_present(*pmd))
- goto out;
ptep = pte_offset_map(pmd, addr);
diff --git a/mm/rmap.c b/mm/rmap.c
index 7df7984..0f47993 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -561,6 +561,27 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma)
return address;
}
+pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd = NULL;
+
+ pgd = pgd_offset(mm, address);
+ if (!pgd_present(*pgd))
+ goto out;
+
+ pud = pud_offset(pgd, address);
+ if (!pud_present(*pud))
+ goto out;
+
+ pmd = pmd_offset(pud, address);
+ if (!pmd_present(*pmd))
+ pmd = NULL;
+out:
+ return pmd;
+}
+
/*
* Check that @page is mapped at @address into @mm.
*
@@ -573,8 +594,6 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma)
pte_t *__page_check_address(struct page *page, struct mm_struct *mm,
unsigned long address, spinlock_t **ptlp, int sync)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
pte_t *pte;
spinlock_t *ptl;
@@ -585,17 +604,10 @@ pte_t *__page_check_address(struct page *page, struct mm_struct *mm,
goto check;
}
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- return NULL;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
+ pmd = mm_find_pmd(mm, address);
+ if (!pmd)
return NULL;
- pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd))
- return NULL;
if (pmd_trans_huge(*pmd))
return NULL;
@@ -1356,16 +1368,8 @@ static int try_to_unmap_cluster(unsigned long cursor, unsigned int *mapcount,
if (end > vma->vm_end)
end = vma->vm_end;
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- return ret;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- return ret;
-
- pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd))
+ pmd = mm_find_pmd(mm, address);
+ if (!pmd)
return ret;
mmun_start = address;
--
1.7.9.5
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