4 files changed, 22 insertions, 10 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 51372a521167..6f58911ece0d 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2735,7 +2735,8 @@ int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
         return ret;
 }
 
-int btree_lock_page_hook(struct page *page)
+static int btree_lock_page_hook(struct page *page, void *data,
+                                void (*flush_fn)(void *))
 {
         struct inode *inode = page->mapping->host;
         struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -2752,7 +2753,10 @@ int btree_lock_page_hook(struct page *page)
         if (!eb)
                 goto out;
 
-        btrfs_tree_lock(eb);
+        if (!btrfs_try_tree_write_lock(eb)) {
+                flush_fn(data);
+                btrfs_tree_lock(eb);
+        }
         btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
 
         if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
@@ -2767,7 +2771,10 @@ int btree_lock_page_hook(struct page *page)
         btrfs_tree_unlock(eb);
         free_extent_buffer(eb);
 out:
-        lock_page(page);
+        if (!trylock_page(page)) {
+                flush_fn(data);
+                lock_page(page);
+        }
         return 0;
 }
 
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index bec3ea4bd67f..e678539c8519 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -83,8 +83,6 @@ int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
                              struct btrfs_fs_info *fs_info);
 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
                        struct btrfs_root *root);
-int btree_lock_page_hook(struct page *page);
-
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 void btrfs_init_lockdep(void);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index f284d4e5f447..b40ba75f4483 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2613,10 +2613,16 @@ retry:
                          * swizzled back from swapper_space to tmpfs file
                          * mapping
                          */
-                        if (tree->ops && tree->ops->write_cache_pages_lock_hook)
-                                tree->ops->write_cache_pages_lock_hook(page);
-                        else
-                                lock_page(page);
+                        if (tree->ops &&
+                            tree->ops->write_cache_pages_lock_hook) {
+                                tree->ops->write_cache_pages_lock_hook(page,
+                                                               data, flush_fn);
+                        } else {
+                                if (!trylock_page(page)) {
+                                        flush_fn(data);
+                                        lock_page(page);
+                                }
+                        }
 
                         if (unlikely(page->mapping != mapping)) {
                                 unlock_page(page);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 325a346369da..cbd4824a7c94 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -86,7 +86,8 @@ struct extent_io_ops {
                                   struct extent_state *other);
         void (*split_extent_hook)(struct inode *inode,
                                   struct extent_state *orig, u64 split);
-        int (*write_cache_pages_lock_hook)(struct page *page);
+        int (*write_cache_pages_lock_hook)(struct page *page, void *data,
+                                           void (*flush_fn)(void *));
 };
 
 struct extent_io_tree {