btrfs: sanitizing ->fs_info, part 3

move assignments to ->fs_info in open_ctree() up, to the place
just after the original allocations.  Assignment for tree_root
becomes a no-op - we'd obtained fs_info from tree_root->fs_info
in the first place.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 5 insertions, 7 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b8dae517f80..06480fcf0fb 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1320,8 +1320,8 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
         root = kzalloc(sizeof(*root), GFP_NOFS);
         if (!root)
                 return ERR_PTR(-ENOMEM);
+        root->fs_info = fs_info;
         if (location->offset == (u64)-1) {
-                root->fs_info = fs_info;
                 ret = find_and_setup_root(tree_root, fs_info,
                                           location->objectid, root);
                 if (ret) {
@@ -1331,7 +1331,6 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
                 goto out;
         }
 
-        root->fs_info = fs_info;
         __setup_root(tree_root->nodesize, tree_root->leafsize,
                      tree_root->sectorsize, tree_root->stripesize,
                      root, fs_info, location->objectid);
@@ -1914,6 +1913,10 @@ struct btrfs_root *open_ctree(struct super_block *sb,
                 err = -ENOMEM;
                 goto fail;
         }
+        chunk_root->fs_info = fs_info;
+        extent_root->fs_info = fs_info;
+        dev_root->fs_info = fs_info;
+        csum_root->fs_info = fs_info;
 
         ret = init_srcu_struct(&fs_info->subvol_srcu);
         if (ret) {
@@ -2057,7 +2060,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         init_waitqueue_head(&fs_info->transaction_blocked_wait);
         init_waitqueue_head(&fs_info->async_submit_wait);
 
-        tree_root->fs_info = fs_info;
         __setup_root(4096, 4096, 4096, 4096, tree_root,
                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 
@@ -2250,7 +2252,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
                                      btrfs_super_chunk_root_level(disk_super));
         generation = btrfs_super_chunk_root_generation(disk_super);
 
-        chunk_root->fs_info = fs_info;
         __setup_root(nodesize, leafsize, sectorsize, stripesize,
                      chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
 
@@ -2300,21 +2301,18 @@ retry_root_backup:
         btrfs_set_root_node(&tree_root->root_item, tree_root->node);
         tree_root->commit_root = btrfs_root_node(tree_root);
 
-        extent_root->fs_info = fs_info;
         ret = find_and_setup_root(tree_root, fs_info,
                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
         if (ret)
                 goto recovery_tree_root;
         extent_root->track_dirty = 1;
 
-        dev_root->fs_info = fs_info;
         ret = find_and_setup_root(tree_root, fs_info,
                                   BTRFS_DEV_TREE_OBJECTID, dev_root);
         if (ret)
                 goto recovery_tree_root;
         dev_root->track_dirty = 1;
 
-        csum_root->fs_info = fs_info;
         ret = find_and_setup_root(tree_root, fs_info,
                                   BTRFS_CSUM_TREE_OBJECTID, csum_root);
         if (ret)