Btrfs: Only prep for btree deletion balances when nodes are mostly empty

[karo-tx-linux.git] / fs / btrfs / extent_io.h

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index e80c6d96b318d7d6445f9f3fde47a56e83005b81..1f9df88afbf6922e9f4af87972f05521ed15e862 100644 (file)
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -22,6 +22,10 @@
 /* flags for bio submission */
 #define EXTENT_BIO_COMPRESSED 1
 
+/* these are bit numbers for test/set bit */
+#define EXTENT_BUFFER_UPTODATE 0
+#define EXTENT_BUFFER_BLOCKING 1
+
 /*
  * page->private values.  Every page that is controlled by the extent
  * map has page->private set to one.
@@ -95,11 +99,19 @@ struct extent_buffer {
        unsigned long map_start;
        unsigned long map_len;
        struct page *first_page;
+       unsigned long bflags;
        atomic_t refs;
-       int flags;
        struct list_head leak_list;
        struct rb_node rb_node;
-       struct mutex mutex;
+
+       /* the spinlock is used to protect most operations */
+       spinlock_t lock;
+
+       /*
+        * when we keep the lock held while blocking, waiters go onto
+        * the wq
+        */
+       wait_queue_head_t lock_wq;
 };
 
 struct extent_map_tree;