mm, hugetlb: return a reserved page to a reserved pool if failed

[platform/adaptation/renesas_rcar/renesas_kernel.git] / mm / hugetlb.c

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index dec5772..0631556 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -572,6 +572,7 @@ retry_cpuset:
                                if (!vma_has_reserves(vma, chg))
                                        break;
 
+                               SetPagePrivate(page);
                                h->resv_huge_pages--;
                                break;
                        }
@@ -629,15 +630,20 @@ static void free_huge_page(struct page *page)
        int nid = page_to_nid(page);
        struct hugepage_subpool *spool =
                (struct hugepage_subpool *)page_private(page);
+       bool restore_reserve;
 
        set_page_private(page, 0);
        page->mapping = NULL;
        BUG_ON(page_count(page));
        BUG_ON(page_mapcount(page));
+       restore_reserve = PagePrivate(page);
 
        spin_lock(&hugetlb_lock);
        hugetlb_cgroup_uncharge_page(hstate_index(h),
                                     pages_per_huge_page(h), page);
+       if (restore_reserve)
+               h->resv_huge_pages++;
+
        if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) {
                /* remove the page from active list */
                list_del(&page->lru);
@@ -2564,8 +2570,7 @@ retry_avoidcopy:
         * at the time of fork() could consume its reserves on COW instead
         * of the full address range.
         */
-       if (!(vma->vm_flags & VM_MAYSHARE) &&
-                       is_vma_resv_set(vma, HPAGE_RESV_OWNER) &&
+       if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) &&
                        old_page != pagecache_page)
                outside_reserve = 1;
 
@@ -2637,6 +2642,8 @@ retry_avoidcopy:
        spin_lock(&mm->page_table_lock);
        ptep = huge_pte_offset(mm, address & huge_page_mask(h));
        if (likely(pte_same(huge_ptep_get(ptep), pte))) {
+               ClearPagePrivate(new_page);
+
                /* Break COW */
                huge_ptep_clear_flush(vma, address, ptep);
                set_huge_pte_at(mm, address, ptep,
@@ -2648,10 +2655,11 @@ retry_avoidcopy:
        }
        spin_unlock(&mm->page_table_lock);
        mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
-       /* Caller expects lock to be held */
-       spin_lock(&mm->page_table_lock);
        page_cache_release(new_page);
        page_cache_release(old_page);
+
+       /* Caller expects lock to be held */
+       spin_lock(&mm->page_table_lock);
        return 0;
 }
 
@@ -2747,6 +2755,7 @@ retry:
                                        goto retry;
                                goto out;
                        }
+                       ClearPagePrivate(page);
 
                        spin_lock(&inode->i_lock);
                        inode->i_blocks += blocks_per_huge_page(h);
@@ -2793,8 +2802,10 @@ retry:
        if (!huge_pte_none(huge_ptep_get(ptep)))
                goto backout;
 
-       if (anon_rmap)
+       if (anon_rmap) {
+               ClearPagePrivate(page);
                hugepage_add_new_anon_rmap(page, vma, address);
+       }
        else
                page_dup_rmap(page);
        new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE)