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.
*
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;
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;
* containing the swap entry, but page not yet written to swap.
*
* And we can skip it on file pages, so long as the filesystem
- * participates in dirty tracking; but need to catch shm and tmpfs
- * and ramfs pages which have been modified since creation by read
- * fault.
+ * participates in dirty tracking (note that this is not only an
+ * optimization but also solves problems caused by dirty flag in
+ * storage key getting set by a write from inside kernel); but need to
+ * catch shm and tmpfs and ramfs pages which have been modified since
+ * creation by read fault.
*
* Note that mapping must be decided above, before decrementing
* mapcount (which luckily provides a barrier): once page is unmapped,
struct vm_area_struct *vma, struct page *check_page)
{
struct mm_struct *mm = vma->vm_mm;
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
pte_t *pte;
pte_t pteval;
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;