6 files changed, 39 insertions, 7 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index fdba4f1b634..0621ab90b1a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -297,6 +297,7 @@ struct btrfs_super_block {
         __le32 leafsize;
         __le32 stripesize;
         __le32 sys_chunk_array_size;
+        __le64 chunk_root_generation;
         u8 root_level;
         u8 chunk_root_level;
         u8 log_root_level;
@@ -448,6 +449,7 @@ struct btrfs_dir_item {
 
 struct btrfs_root_item {
         struct btrfs_inode_item inode;
+        __le64 generation;
         __le64 root_dirid;
         __le64 bytenr;
         __le64 byte_limit;
@@ -1396,10 +1398,14 @@ static inline int btrfs_is_leaf(struct extent_buffer *eb)
 }
 
 /* struct btrfs_root_item */
+BTRFS_SETGET_FUNCS(disk_root_generation, struct btrfs_root_item,
+                   generation, 64);
 BTRFS_SETGET_FUNCS(disk_root_refs, struct btrfs_root_item, refs, 32);
 BTRFS_SETGET_FUNCS(disk_root_bytenr, struct btrfs_root_item, bytenr, 64);
 BTRFS_SETGET_FUNCS(disk_root_level, struct btrfs_root_item, level, 8);
 
+BTRFS_SETGET_STACK_FUNCS(root_generation, struct btrfs_root_item,
+                         generation, 64);
 BTRFS_SETGET_STACK_FUNCS(root_bytenr, struct btrfs_root_item, bytenr, 64);
 BTRFS_SETGET_STACK_FUNCS(root_level, struct btrfs_root_item, level, 8);
 BTRFS_SETGET_STACK_FUNCS(root_dirid, struct btrfs_root_item, root_dirid, 64);
@@ -1416,6 +1422,8 @@ BTRFS_SETGET_STACK_FUNCS(super_generation, struct btrfs_super_block,
 BTRFS_SETGET_STACK_FUNCS(super_root, struct btrfs_super_block, root, 64);
 BTRFS_SETGET_STACK_FUNCS(super_sys_array_size,
                          struct btrfs_super_block, sys_chunk_array_size, 32);
+BTRFS_SETGET_STACK_FUNCS(super_chunk_root_generation,
+                         struct btrfs_super_block, chunk_root_generation, 64);
 BTRFS_SETGET_STACK_FUNCS(super_root_level, struct btrfs_super_block,
                          root_level, 8);
 BTRFS_SETGET_STACK_FUNCS(super_chunk_root, struct btrfs_super_block,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index d1137d7ea8d..94b4e50f6b2 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -832,6 +832,7 @@ static int find_and_setup_root(struct btrfs_root *tree_root,
 {
         int ret;
         u32 blocksize;
+        u64 generation;
 
         __setup_root(tree_root->nodesize, tree_root->leafsize,
                      tree_root->sectorsize, tree_root->stripesize,
@@ -840,9 +841,10 @@ static int find_and_setup_root(struct btrfs_root *tree_root,
                                    &root->root_item, &root->root_key);
         BUG_ON(ret);
 
+        generation = btrfs_root_generation(&root->root_item);
         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-                                     blocksize, 0);
+                                     blocksize, generation);
         BUG_ON(!root->node);
         return 0;
 }
@@ -929,6 +931,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
         struct btrfs_path *path;
         struct extent_buffer *l;
         u64 highest_inode;
+        u64 generation;
         u32 blocksize;
         int ret = 0;
 
@@ -970,9 +973,10 @@ out:
                 kfree(root);
                 return ERR_PTR(ret);
         }
+        generation = btrfs_root_generation(&root->root_item);
         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-                                     blocksize, 0);
+                                     blocksize, generation);
         BUG_ON(!root->node);
 insert:
         if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
@@ -1357,6 +1361,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         u32 leafsize;
         u32 blocksize;
         u32 stripesize;
+        u64 generation;
         struct buffer_head *bh;
         struct btrfs_root *extent_root = kzalloc(sizeof(struct btrfs_root),
                                                  GFP_NOFS);
@@ -1596,13 +1601,14 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
         blocksize = btrfs_level_size(tree_root,
                                      btrfs_super_chunk_root_level(disk_super));
+        generation = btrfs_super_chunk_root_generation(disk_super);
 
         __setup_root(nodesize, leafsize, sectorsize, stripesize,
                      chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
 
         chunk_root->node = read_tree_block(chunk_root,
                                            btrfs_super_chunk_root(disk_super),
-                                           blocksize, 0);
+                                           blocksize, generation);
         BUG_ON(!chunk_root->node);
 
         read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
@@ -1618,11 +1624,11 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
         blocksize = btrfs_level_size(tree_root,
                                      btrfs_super_root_level(disk_super));
-
+        generation = btrfs_super_generation(disk_super);
 
         tree_root->node = read_tree_block(tree_root,
                                           btrfs_super_root(disk_super),
-                                          blocksize, 0);
+                                          blocksize, generation);
         if (!tree_root->node)
                 goto fail_sb_buffer;
 
@@ -1672,15 +1678,16 @@ struct btrfs_root *open_ctree(struct super_block *sb,
                              log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
 
                 log_tree_root->node = read_tree_block(tree_root, bytenr,
-                                                      blocksize, 0);
+                                                      blocksize,
+                                                      generation + 1);
                 ret = btrfs_recover_log_trees(log_tree_root);
                 BUG_ON(ret);
         }
+        fs_info->last_trans_committed = btrfs_super_generation(disk_super);
 
         ret = btrfs_cleanup_reloc_trees(tree_root);
         BUG_ON(ret);
 
-        fs_info->last_trans_committed = btrfs_super_generation(disk_super);
         return tree_root;
 
 fail_cleaner:
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 564260872c7..155c8dc56a2 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4428,6 +4428,7 @@ static int noinline init_reloc_tree(struct btrfs_trans_handle *trans,
         btrfs_set_root_refs(root_item, 0);
         btrfs_set_root_bytenr(root_item, eb->start);
         btrfs_set_root_level(root_item, btrfs_header_level(eb));
+        btrfs_set_root_generation(root_item, trans->transid);
 
         btrfs_tree_unlock(eb);
         free_extent_buffer(eb);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 1136ce2febc..fd3c8b5676c 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -108,6 +108,7 @@ static noinline int create_subvol(struct btrfs_root *root,
         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 
         btrfs_set_root_bytenr(&root_item, leaf->start);
+        btrfs_set_root_generation(&root_item, trans->transid);
         btrfs_set_root_level(&root_item, 0);
         btrfs_set_root_refs(&root_item, 1);
         btrfs_set_root_used(&root_item, 0);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 48b455fdaac..924af6f2aea 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -439,6 +439,7 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans,
                                        root->node->start);
                 btrfs_set_root_level(&root->root_item,
                                      btrfs_header_level(root->node));
+                btrfs_set_root_generation(&root->root_item, trans->transid);
                 ret = btrfs_update_root(trans, tree_root,
                                         &root->root_key,
                                         &root->root_item);
@@ -456,6 +457,12 @@ int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
 {
         struct btrfs_fs_info *fs_info = root->fs_info;
         struct list_head *next;
+        struct extent_buffer *eb;
+
+        eb = btrfs_lock_root_node(fs_info->tree_root);
+        btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb, 0);
+        btrfs_tree_unlock(eb);
+        free_extent_buffer(eb);
 
         while(!list_empty(&fs_info->dirty_cowonly_roots)) {
                 next = fs_info->dirty_cowonly_roots.next;
@@ -559,6 +566,9 @@ static noinline int add_dirty_roots(struct btrfs_trans_handle *trans,
                                               root->node->start);
                         btrfs_set_root_level(&root->root_item,
                                              btrfs_header_level(root->node));
+                        btrfs_set_root_generation(&root->root_item,
+                                                  root->root_key.offset);
+
                         err = btrfs_insert_root(trans, root->fs_info->tree_root,
                                                 &root->root_key,
                                                 &root->root_item);
@@ -756,6 +766,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 
         btrfs_set_root_bytenr(new_root_item, tmp->start);
         btrfs_set_root_level(new_root_item, btrfs_header_level(tmp));
+        btrfs_set_root_generation(new_root_item, trans->transid);
         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
                                 new_root_item);
         btrfs_tree_unlock(tmp);
@@ -946,6 +957,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                                    chunk_root->node->start);
         btrfs_set_super_chunk_root_level(&root->fs_info->super_copy,
                                          btrfs_header_level(chunk_root->node));
+        btrfs_set_super_chunk_root_generation(&root->fs_info->super_copy,
+                                btrfs_header_generation(chunk_root->node));
 
         if (!root->fs_info->log_root_recovering) {
                 btrfs_set_super_log_root(&root->fs_info->super_copy, 0);
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 835daed5561..e0201c3a7dc 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -117,6 +117,7 @@ int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 
         btrfs_set_root_bytenr(&root_item, leaf->start);
+        btrfs_set_root_generation(&root_item, trans->transid);
         btrfs_set_root_level(&root_item, 0);
         btrfs_set_root_refs(&root_item, 0);
         btrfs_set_root_used(&root_item, 0);
@@ -2065,6 +2066,7 @@ static int update_log_root(struct btrfs_trans_handle *trans,
                 return 0;
 
         btrfs_set_root_bytenr(&log->root_item, log->node->start);
+        btrfs_set_root_generation(&log->root_item, trans->transid);
         btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
         ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
                                 &log->root_key, &log->root_item);