thp: remove assumptions on pgtable_t type

[mirror_ubuntu-artful-kernel.git] / mm / huge_memory.c

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index e19cc426c522e32b19922532d2380b9d9c37c7a9..9ea6d1953765e5a19dd237175eacd0e2e70e5565 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -598,19 +598,6 @@ out:
 }
 __setup("transparent_hugepage=", setup_transparent_hugepage);
 
-static void prepare_pmd_huge_pte(pgtable_t pgtable,
-                                struct mm_struct *mm)
-{
-       assert_spin_locked(&mm->page_table_lock);
-
-       /* FIFO */
-       if (!mm->pmd_huge_pte)
-               INIT_LIST_HEAD(&pgtable->lru);
-       else
-               list_add(&pgtable->lru, &mm->pmd_huge_pte->lru);
-       mm->pmd_huge_pte = pgtable;
-}
-
 static inline pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma)
 {
        if (likely(vma->vm_flags & VM_WRITE))
@@ -652,7 +639,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
                 */
                page_add_new_anon_rmap(page, vma, haddr);
                set_pmd_at(mm, haddr, pmd, entry);
-               prepare_pmd_huge_pte(pgtable, mm);
+               pgtable_trans_huge_deposit(mm, pgtable);
                add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
                mm->nr_ptes++;
                spin_unlock(&mm->page_table_lock);
@@ -778,7 +765,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
        pmdp_set_wrprotect(src_mm, addr, src_pmd);
        pmd = pmd_mkold(pmd_wrprotect(pmd));
        set_pmd_at(dst_mm, addr, dst_pmd, pmd);
-       prepare_pmd_huge_pte(pgtable, dst_mm);
+       pgtable_trans_huge_deposit(dst_mm, pgtable);
        dst_mm->nr_ptes++;
 
        ret = 0;
@@ -789,25 +776,6 @@ out:
        return ret;
 }
 
-/* no "address" argument so destroys page coloring of some arch */
-pgtable_t get_pmd_huge_pte(struct mm_struct *mm)
-{
-       pgtable_t pgtable;
-
-       assert_spin_locked(&mm->page_table_lock);
-
-       /* FIFO */
-       pgtable = mm->pmd_huge_pte;
-       if (list_empty(&pgtable->lru))
-               mm->pmd_huge_pte = NULL;
-       else {
-               mm->pmd_huge_pte = list_entry(pgtable->lru.next,
-                                             struct page, lru);
-               list_del(&pgtable->lru);
-       }
-       return pgtable;
-}
-
 static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
                                        struct vm_area_struct *vma,
                                        unsigned long address,
@@ -863,7 +831,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
        pmdp_clear_flush_notify(vma, haddr, pmd);
        /* leave pmd empty until pte is filled */
 
-       pgtable = get_pmd_huge_pte(mm);
+       pgtable = pgtable_trans_huge_withdraw(mm);
        pmd_populate(mm, &_pmd, pgtable);
 
        for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) {
@@ -1028,7 +996,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
        if (__pmd_trans_huge_lock(pmd, vma) == 1) {
                struct page *page;
                pgtable_t pgtable;
-               pgtable = get_pmd_huge_pte(tlb->mm);
+               pgtable = pgtable_trans_huge_withdraw(tlb->mm);
                page = pmd_page(*pmd);
                pmd_clear(pmd);
                tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
@@ -1345,11 +1313,11 @@ static int __split_huge_page_map(struct page *page,
        pmd = page_check_address_pmd(page, mm, address,
                                     PAGE_CHECK_ADDRESS_PMD_SPLITTING_FLAG);
        if (pmd) {
-               pgtable = get_pmd_huge_pte(mm);
+               pgtable = pgtable_trans_huge_withdraw(mm);
                pmd_populate(mm, &_pmd, pgtable);
 
-               for (i = 0, haddr = address; i < HPAGE_PMD_NR;
-                    i++, haddr += PAGE_SIZE) {
+               haddr = address;
+               for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) {
                        pte_t *pte, entry;
                        BUG_ON(PageCompound(page+i));
                        entry = mk_pte(page + i, vma->vm_page_prot);
@@ -2017,8 +1985,6 @@ static void collapse_huge_page(struct mm_struct *mm,
        pte_unmap(pte);
        __SetPageUptodate(new_page);
        pgtable = pmd_pgtable(_pmd);
-       VM_BUG_ON(page_count(pgtable) != 1);
-       VM_BUG_ON(page_mapcount(pgtable) != 0);
 
        _pmd = mk_pmd(new_page, vma->vm_page_prot);
        _pmd = maybe_pmd_mkwrite(pmd_mkdirty(_pmd), vma);
@@ -2036,7 +2002,7 @@ static void collapse_huge_page(struct mm_struct *mm,
        page_add_new_anon_rmap(new_page, vma, address);
        set_pmd_at(mm, address, pmd, _pmd);
        update_mmu_cache(vma, address, _pmd);
-       prepare_pmd_huge_pte(pgtable, mm);
+       pgtable_trans_huge_deposit(mm, pgtable);
        spin_unlock(&mm->page_table_lock);
 
        *hpage = NULL;