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-rw-r--r--mm/rmap.c138
1 files changed, 0 insertions, 138 deletions
diff --git a/mm/rmap.c b/mm/rmap.c
index 80525820aada..8774791e2809 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -708,144 +708,6 @@ out:
return pmd;
}
-/*
- * Check that @page is mapped at @address into @mm.
- *
- * If @sync is false, page_check_address may perform a racy check to avoid
- * the page table lock when the pte is not present (helpful when reclaiming
- * highly shared pages).
- *
- * On success returns with pte mapped and locked.
- */
-pte_t *__page_check_address(struct page *page, struct mm_struct *mm,
- unsigned long address, spinlock_t **ptlp, int sync)
-{
- pmd_t *pmd;
- pte_t *pte;
- spinlock_t *ptl;
-
- if (unlikely(PageHuge(page))) {
- /* when pud is not present, pte will be NULL */
- pte = huge_pte_offset(mm, address);
- if (!pte)
- return NULL;
-
- ptl = huge_pte_lockptr(page_hstate(page), mm, pte);
- goto check;
- }
-
- pmd = mm_find_pmd(mm, address);
- if (!pmd)
- return NULL;
-
- pte = pte_offset_map(pmd, address);
- /* Make a quick check before getting the lock */
- if (!sync && !pte_present(*pte)) {
- pte_unmap(pte);
- return NULL;
- }
-
- ptl = pte_lockptr(mm, pmd);
-check:
- spin_lock(ptl);
- if (pte_present(*pte) && page_to_pfn(page) == pte_pfn(*pte)) {
- *ptlp = ptl;
- return pte;
- }
- pte_unmap_unlock(pte, ptl);
- return NULL;
-}
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-/*
- * Check that @page is mapped at @address into @mm. In contrast to
- * page_check_address(), this function can handle transparent huge pages.
- *
- * On success returns true with pte mapped and locked. For PMD-mapped
- * transparent huge pages *@ptep is set to NULL.
- */
-bool page_check_address_transhuge(struct page *page, struct mm_struct *mm,
- unsigned long address, pmd_t **pmdp,
- pte_t **ptep, spinlock_t **ptlp)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
- spinlock_t *ptl;
-
- if (unlikely(PageHuge(page))) {
- /* when pud is not present, pte will be NULL */
- pte = huge_pte_offset(mm, address);
- if (!pte)
- return false;
-
- ptl = huge_pte_lockptr(page_hstate(page), mm, pte);
- pmd = NULL;
- goto check_pte;
- }
-
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- return false;
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- return false;
- pmd = pmd_offset(pud, address);
-
- if (pmd_trans_huge(*pmd)) {
- ptl = pmd_lock(mm, pmd);
- if (!pmd_present(*pmd))
- goto unlock_pmd;
- if (unlikely(!pmd_trans_huge(*pmd))) {
- spin_unlock(ptl);
- goto map_pte;
- }
-
- if (pmd_page(*pmd) != page)
- goto unlock_pmd;
-
- pte = NULL;
- goto found;
-unlock_pmd:
- spin_unlock(ptl);
- return false;
- } else {
- pmd_t pmde = *pmd;
-
- barrier();
- if (!pmd_present(pmde) || pmd_trans_huge(pmde))
- return false;
- }
-map_pte:
- pte = pte_offset_map(pmd, address);
- if (!pte_present(*pte)) {
- pte_unmap(pte);
- return false;
- }
-
- ptl = pte_lockptr(mm, pmd);
-check_pte:
- spin_lock(ptl);
-
- if (!pte_present(*pte)) {
- pte_unmap_unlock(pte, ptl);
- return false;
- }
-
- /* THP can be referenced by any subpage */
- if (pte_pfn(*pte) - page_to_pfn(page) >= hpage_nr_pages(page)) {
- pte_unmap_unlock(pte, ptl);
- return false;
- }
-found:
- *ptep = pte;
- *pmdp = pmd;
- *ptlp = ptl;
- return true;
-}
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-
struct page_referenced_arg {
int mapcount;
int referenced;