ext4: Use an rbtree for tracking blocks freed during transaction.

With this patch we track the block freed during a transaction using
red-black tree.  We also make sure contiguous blocks freed are collected
in one node in the tree.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 16 insertions, 10 deletions

diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h
index b3b4828f8b8..9e815c4e37d 100644
--- a/fs/ext4/mballoc.h
+++ b/fs/ext4/mballoc.h
@@ -98,23 +98,29 @@
 
 static struct kmem_cache *ext4_pspace_cachep;
 static struct kmem_cache *ext4_ac_cachep;
+static struct kmem_cache *ext4_free_ext_cachep;
 
-#ifdef EXT4_BB_MAX_BLOCKS
-#undef EXT4_BB_MAX_BLOCKS
-#endif
-#define EXT4_BB_MAX_BLOCKS      30
+struct ext4_free_data {
+        /* this links the free block information from group_info */
+        struct rb_node node;
 
-struct ext4_free_metadata {
-        ext4_group_t group;
-        unsigned short num;
-        ext4_grpblk_t  blocks[EXT4_BB_MAX_BLOCKS];
+        /* this links the free block information from ext4_sb_info */
         struct list_head list;
+
+        /* group which free block extent belongs */
+        ext4_group_t group;
+
+        /* free block extent */
+        ext4_grpblk_t start_blk;
+        ext4_grpblk_t count;
+
+        /* transaction which freed this extent */
+        tid_t   t_tid;
 };
 
 struct ext4_group_info {
         unsigned long   bb_state;
-        unsigned long   bb_tid;
-        struct ext4_free_metadata *bb_md_cur;
+        struct rb_root  bb_free_root;
         unsigned short  bb_first_free;
         unsigned short  bb_free;
         unsigned short  bb_fragments;