memcg, oom: don't require __GFP_FS when invoking memcg OOM killer

[linux-2.6-block.git] / mm / huge_memory.c

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index de1f15969e2782edd648a43fc5e7c6d7edacb38b..483b07b2d6ae12e21bd478ddad2640ba0601fc91 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2497,6 +2497,8 @@ static void __split_huge_page(struct page *page, struct list_head *list,
        struct page *head = compound_head(page);
        pg_data_t *pgdat = page_pgdat(head);
        struct lruvec *lruvec;
+       struct address_space *swap_cache = NULL;
+       unsigned long offset = 0;
        int i;
 
        lruvec = mem_cgroup_page_lruvec(head, pgdat);
@@ -2504,6 +2506,14 @@ static void __split_huge_page(struct page *page, struct list_head *list,
        /* complete memcg works before add pages to LRU */
        mem_cgroup_split_huge_fixup(head);
 
+       if (PageAnon(head) && PageSwapCache(head)) {
+               swp_entry_t entry = { .val = page_private(head) };
+
+               offset = swp_offset(entry);
+               swap_cache = swap_address_space(entry);
+               xa_lock(&swap_cache->i_pages);
+       }
+
        for (i = HPAGE_PMD_NR - 1; i >= 1; i--) {
                __split_huge_page_tail(head, i, lruvec, list);
                /* Some pages can be beyond i_size: drop them from page cache */
@@ -2513,6 +2523,12 @@ static void __split_huge_page(struct page *page, struct list_head *list,
                        if (IS_ENABLED(CONFIG_SHMEM) && PageSwapBacked(head))
                                shmem_uncharge(head->mapping->host, 1);
                        put_page(head + i);
+               } else if (!PageAnon(page)) {
+                       __xa_store(&head->mapping->i_pages, head[i].index,
+                                       head + i, 0);
+               } else if (swap_cache) {
+                       __xa_store(&swap_cache->i_pages, offset + i,
+                                       head + i, 0);
                }
        }
 
@@ -2523,10 +2539,12 @@ static void __split_huge_page(struct page *page, struct list_head *list,
        /* See comment in __split_huge_page_tail() */
        if (PageAnon(head)) {
                /* Additional pin to swap cache */
-               if (PageSwapCache(head))
+               if (PageSwapCache(head)) {
                        page_ref_add(head, 2);
-               else
+                       xa_unlock(&swap_cache->i_pages);
+               } else {
                        page_ref_inc(head);
+               }
        } else {
                /* Additional pin to page cache */
                page_ref_add(head, 2);