Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index c1b1708..fd57442 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -183,8 +183,8 @@ static int sync_page(void *word)
  * these two operations is that if a dirty page/buffer is encountered, it must
  * be waited upon, and not just skipped over.
  */
-static int __filemap_fdatawrite_range(struct address_space *mapping,
-       loff_t start, loff_t end, int sync_mode)
+int __filemap_fdatawrite_range(struct address_space *mapping, loff_t start,
+                               loff_t end, int sync_mode)
 {
        int ret;
        struct writeback_control wbc = {
@@ -213,8 +213,8 @@ int filemap_fdatawrite(struct address_space *mapping)
 }
 EXPORT_SYMBOL(filemap_fdatawrite);
 
-static int filemap_fdatawrite_range(struct address_space *mapping,
-       loff_t start, loff_t end)
+static int filemap_fdatawrite_range(struct address_space *mapping, loff_t start,
+                               loff_t end)
 {
        return __filemap_fdatawrite_range(mapping, start, end, WB_SYNC_ALL);
 }
@@ -233,7 +233,7 @@ EXPORT_SYMBOL(filemap_flush);
  * Wait for writeback to complete against pages indexed by start->end
  * inclusive
  */
-static int wait_on_page_writeback_range(struct address_space *mapping,
+int wait_on_page_writeback_range(struct address_space *mapping,
                                pgoff_t start, pgoff_t end)
 {
        struct pagevec pvec;
@@ -697,6 +697,38 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start,
        return ret;
 }
 
+/**
+ * find_get_pages_contig - gang contiguous pagecache lookup
+ * @mapping:   The address_space to search
+ * @index:     The starting page index
+ * @nr_pages:  The maximum number of pages
+ * @pages:     Where the resulting pages are placed
+ *
+ * find_get_pages_contig() works exactly like find_get_pages(), except
+ * that the returned number of pages are guaranteed to be contiguous.
+ *
+ * find_get_pages_contig() returns the number of pages which were found.
+ */
+unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index,
+                              unsigned int nr_pages, struct page **pages)
+{
+       unsigned int i;
+       unsigned int ret;
+
+       read_lock_irq(&mapping->tree_lock);
+       ret = radix_tree_gang_lookup(&mapping->page_tree,
+                               (void **)pages, index, nr_pages);
+       for (i = 0; i < ret; i++) {
+               if (pages[i]->mapping == NULL || pages[i]->index != index)
+                       break;
+
+               page_cache_get(pages[i]);
+               index++;
+       }
+       read_unlock_irq(&mapping->tree_lock);
+       return i;
+}
+
 /*
  * Like find_get_pages, except we only return pages which are tagged with
  * `tag'.   We update *index to index the next page for the traversal.