Btrfs: Add the ability to find and remove dead roots after a crash.

[linux-2.6-block.git] / fs / btrfs / disk-io.c

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 865a284aa06ce03b582c21c56809f718d961ff73..d7615e1578ccc0af2a776996bb8ac8a97eaf9dab 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -326,8 +326,8 @@ static int find_and_setup_root(int blocksize,
        return 0;
 }
 
-struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
-                                     struct btrfs_key *location)
+struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
+                                              struct btrfs_key *location)
 {
        struct btrfs_root *root;
        struct btrfs_root *tree_root = fs_info->tree_root;
@@ -336,11 +336,7 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
        u64 highest_inode;
        int ret = 0;
 
-       root = radix_tree_lookup(&fs_info->fs_roots_radix,
-                                (unsigned long)location->objectid);
-       if (root)
-               return root;
-       root = kmalloc(sizeof(*root), GFP_NOFS);
+       root = kzalloc(sizeof(*root), GFP_NOFS);
        if (!root)
                return ERR_PTR(-ENOMEM);
        if (location->offset == (u64)-1) {
@@ -383,6 +379,28 @@ out:
        BUG_ON(!root->node);
 insert:
        root->ref_cows = 1;
+       ret = btrfs_find_highest_inode(root, &highest_inode);
+       if (ret == 0) {
+               root->highest_inode = highest_inode;
+               root->last_inode_alloc = highest_inode;
+       }
+       return root;
+}
+
+struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
+                                     struct btrfs_key *location)
+{
+       struct btrfs_root *root;
+       int ret;
+
+       root = radix_tree_lookup(&fs_info->fs_roots_radix,
+                                (unsigned long)location->objectid);
+       if (root)
+               return root;
+
+       root = btrfs_read_fs_root_no_radix(fs_info, location);
+       if (IS_ERR(root))
+               return root;
        ret = radix_tree_insert(&fs_info->fs_roots_radix,
                                (unsigned long)root->root_key.objectid,
                                root);
@@ -391,11 +409,6 @@ insert:
                kfree(root);
                return ERR_PTR(ret);
        }
-       ret = btrfs_find_highest_inode(root, &highest_inode);
-       if (ret == 0) {
-               root->highest_inode = highest_inode;
-               root->last_inode_alloc = highest_inode;
-       }
        return root;
 }
 
@@ -489,6 +502,9 @@ struct btrfs_root *open_ctree(struct super_block *sb)
        btrfs_read_block_groups(extent_root);
 
        fs_info->generation = btrfs_super_generation(disk_super) + 1;
+       ret = btrfs_find_dead_roots(tree_root);
+       if (ret)
+               goto fail_tree_root;
        mutex_unlock(&fs_info->fs_mutex);
        return tree_root;
 
@@ -538,7 +554,7 @@ int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
        return 0;
 }
 
-static int free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
+int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 {
        radix_tree_delete(&fs_info->fs_roots_radix,
                          (unsigned long)root->root_key.objectid);
@@ -565,7 +581,7 @@ static int del_fs_roots(struct btrfs_fs_info *fs_info)
                if (!ret)
                        break;
                for (i = 0; i < ret; i++)
-                       free_fs_root(fs_info, gang[i]);
+                       btrfs_free_fs_root(fs_info, gang[i]);
        }
        return 0;
 }