Btrfs: add extra flushing for renames and truncates

[linux-2.6-omap-h63xx.git] / fs / btrfs / ctree.h

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2737facbd341b083d5e1e9be942d6e873f485162..f48905ee5240ee37e80e9145836e57c052d0be1e 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -45,6 +45,13 @@ struct btrfs_ordered_sum;
 
 #define BTRFS_MAX_LEVEL 8
 
+/*
+ * files bigger than this get some pre-flushing when they are added
+ * to the ordered operations list.  That way we limit the total
+ * work done by the commit
+ */
+#define BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT (8 * 1024 * 1024)
+
 /* holds pointers to all of the tree roots */
 #define BTRFS_ROOT_TREE_OBJECTID 1ULL
 
@@ -727,6 +734,15 @@ struct btrfs_fs_info {
        struct mutex volume_mutex;
        struct mutex tree_reloc_mutex;
 
+       /*
+        * this protects the ordered operations list only while we are
+        * processing all of the entries on it.  This way we make
+        * sure the commit code doesn't find the list temporarily empty
+        * because another function happens to be doing non-waiting preflush
+        * before jumping into the main commit.
+        */
+       struct mutex ordered_operations_mutex;
+
        struct list_head trans_list;
        struct list_head hashers;
        struct list_head dead_roots;
@@ -741,9 +757,28 @@ struct btrfs_fs_info {
         * ordered extents
         */
        spinlock_t ordered_extent_lock;
+
+       /*
+        * all of the data=ordered extents pending writeback
+        * these can span multiple transactions and basically include
+        * every dirty data page that isn't from nodatacow
+        */
        struct list_head ordered_extents;
+
+       /*
+        * all of the inodes that have delalloc bytes.  It is possible for
+        * this list to be empty even when there is still dirty data=ordered
+        * extents waiting to finish IO.
+        */
        struct list_head delalloc_inodes;
 
+       /*
+        * special rename and truncate targets that must be on disk before
+        * we're allowed to commit.  This is basically the ext3 style
+        * data=ordered list.
+        */
+       struct list_head ordered_operations;
+
        /*
         * there is a pool of worker threads for checksumming during writes
         * and a pool for checksumming after reads.  This is because readers