1 files changed, 38 insertions, 27 deletions

diff --git a/mm/readahead.c b/mm/readahead.c
index bec83c15a78f..133b6d525513 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -17,19 +17,6 @@
 #include <linux/pagevec.h>
 #include <linux/pagemap.h>
 
-void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-}
-EXPORT_SYMBOL(default_unplug_io_fn);
-
-struct backing_dev_info default_backing_dev_info = {
-        .ra_pages       = VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE,
-        .state          = 0,
-        .capabilities   = BDI_CAP_MAP_COPY,
-        .unplug_io_fn   = default_unplug_io_fn,
-};
-EXPORT_SYMBOL_GPL(default_backing_dev_info);
-
 /*
  * Initialise a struct file's readahead state.  Assumes that the caller has
  * memset *ra to zero.
@@ -44,6 +31,42 @@ EXPORT_SYMBOL_GPL(file_ra_state_init);
 
 #define list_to_page(head) (list_entry((head)->prev, struct page, lru))
 
+/*
+ * see if a page needs releasing upon read_cache_pages() failure
+ * - the caller of read_cache_pages() may have set PG_private or PG_fscache
+ *   before calling, such as the NFS fs marking pages that are cached locally
+ *   on disk, thus we need to give the fs a chance to clean up in the event of
+ *   an error
+ */
+static void read_cache_pages_invalidate_page(struct address_space *mapping,
+                                             struct page *page)
+{
+        if (page_has_private(page)) {
+                if (!trylock_page(page))
+                        BUG();
+                page->mapping = mapping;
+                do_invalidatepage(page, 0);
+                page->mapping = NULL;
+                unlock_page(page);
+        }
+        page_cache_release(page);
+}
+
+/*
+ * release a list of pages, invalidating them first if need be
+ */
+static void read_cache_pages_invalidate_pages(struct address_space *mapping,
+                                              struct list_head *pages)
+{
+        struct page *victim;
+
+        while (!list_empty(pages)) {
+                victim = list_to_page(pages);
+                list_del(&victim->lru);
+                read_cache_pages_invalidate_page(mapping, victim);
+        }
+}
+
 /**
  * read_cache_pages - populate an address space with some pages & start reads against them
  * @mapping: the address_space
@@ -65,14 +88,14 @@ int read_cache_pages(struct address_space *mapping, struct list_head *pages,
                 list_del(&page->lru);
                 if (add_to_page_cache_lru(page, mapping,
                                         page->index, GFP_KERNEL)) {
-                        page_cache_release(page);
+                        read_cache_pages_invalidate_page(mapping, page);
                         continue;
                 }
                 page_cache_release(page);
 
                 ret = filler(data, page);
                 if (unlikely(ret)) {
-                        put_pages_list(pages);
+                        read_cache_pages_invalidate_pages(mapping, pages);
                         break;
                 }
                 task_io_account_read(PAGE_CACHE_SIZE);
@@ -233,18 +256,6 @@ unsigned long max_sane_readahead(unsigned long nr)
                 + node_page_state(numa_node_id(), NR_FREE_PAGES)) / 2);
 }
 
-static int __init readahead_init(void)
-{
-        int err;
-
-        err = bdi_init(&default_backing_dev_info);
-        if (!err)
-                bdi_register(&default_backing_dev_info, NULL, "default");
-
-        return err;
-}
-subsys_initcall(readahead_init);
-
 /*
  * Submit IO for the read-ahead request in file_ra_state.
  */