btrfsck: check root back/forward references
authorYan, Zheng <zheng.yan@oracle.com>
Mon, 21 Sep 2009 20:03:57 +0000 (16:03 -0400)
committerChris Mason <chris.mason@oracle.com>
Mon, 21 Sep 2009 20:03:57 +0000 (16:03 -0400)
This patch adds semantic checks for links to snapshot/subvolume and
root back/forward references.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfsck.c

index 40c90f8..73f1836 100644 (file)
--- a/btrfsck.c
+++ b/btrfsck.c
@@ -36,7 +36,7 @@ static u64 total_fs_tree_bytes = 0;
 static u64 btree_space_waste = 0;
 static u64 data_bytes_allocated = 0;
 static u64 data_bytes_referenced = 0;
-int found_old_backref = 0;
+static int found_old_backref = 0;
 
 struct extent_backref {
        struct list_head list;
@@ -100,7 +100,11 @@ struct inode_backref {
 #define REF_ERR_DUP_INODE_REF          (1 << 5)
 #define REF_ERR_INDEX_UNMATCH          (1 << 6)
 #define REF_ERR_FILETYPE_UNMATCH       (1 << 7)
-#define REF_ERR_NAME_TOO_LONG          (1 << 8)
+#define REF_ERR_NAME_TOO_LONG          (1 << 8) // 100
+#define REF_ERR_NO_ROOT_REF            (1 << 9)
+#define REF_ERR_NO_ROOT_BACKREF                (1 << 10)
+#define REF_ERR_DUP_ROOT_REF           (1 << 11)
+#define REF_ERR_DUP_ROOT_BACKREF       (1 << 12)
 
 struct inode_record {
        struct list_head backrefs;
@@ -144,6 +148,29 @@ struct inode_record {
 #define I_ERR_SOME_CSUM_MISSING                (1 << 12)
 #define I_ERR_LINK_COUNT_WRONG         (1 << 13)
 
+struct root_backref {
+       struct list_head list;
+       unsigned int found_dir_item:1;
+       unsigned int found_dir_index:1;
+       unsigned int found_back_ref:1;
+       unsigned int found_forward_ref:1;
+       unsigned int reachable:1;
+       int errors;
+       u64 ref_root;
+       u64 dir;
+       u64 index;
+       u16 namelen;
+       char name[0];
+};
+
+struct root_record {
+       struct list_head backrefs;
+       struct cache_extent cache;
+       unsigned int found_root_item:1;
+       u64 objectid;
+       u32 found_ref;
+};
+
 struct ptr_node {
        struct cache_extent cache;
        void *data;
@@ -151,6 +178,7 @@ struct ptr_node {
 
 struct shared_node {
        struct cache_extent cache;
+       struct cache_tree root_cache;
        struct cache_tree inode_cache;
        struct inode_record *current;
        u32 refs;
@@ -258,6 +286,14 @@ static void free_inode_rec(struct inode_record *rec)
        free(rec);
 }
 
+static int can_free_inode_rec(struct inode_record *rec)
+{
+       if (!rec->errors && rec->checked && rec->found_inode_item &&
+           rec->nlink == rec->found_link && list_empty(&rec->backrefs))
+               return 1;
+       return 0;
+}
+
 static void maybe_free_inode_rec(struct cache_tree *inode_cache,
                                 struct inode_record *rec)
 {
@@ -309,8 +345,7 @@ static void maybe_free_inode_rec(struct cache_tree *inode_cache,
        }
 
        BUG_ON(rec->refs != 1);
-       if (!rec->errors && rec->nlink == rec->found_link &&
-           list_empty(&rec->backrefs)) {
+       if (can_free_inode_rec(rec)) {
                cache = find_cache_extent(inode_cache, rec->ino, 1);
                node = container_of(cache, struct ptr_node, cache);
                BUG_ON(node->data != rec);
@@ -338,14 +373,12 @@ static int check_orphan_item(struct btrfs_root *root, u64 ino)
        return ret;
 }
 
-static int process_inode_item(struct btrfs_root *root,
-                             struct extent_buffer *eb,
+static int process_inode_item(struct extent_buffer *eb,
                              int slot, struct btrfs_key *key,
                              struct shared_node *active_node)
 {
        struct inode_record *rec;
        struct btrfs_inode_item *item;
-       int ret;
 
        rec = active_node->current;
        BUG_ON(rec->ino != key->objectid || rec->refs > 1);
@@ -361,11 +394,8 @@ static int process_inode_item(struct btrfs_root *root,
        if (btrfs_inode_flags(eb, item) & BTRFS_INODE_NODATASUM)
                rec->nodatasum = 1;
        rec->found_inode_item = 1;
-       if (rec->nlink == 0) {
-               ret = check_orphan_item(root, rec->ino);
-               if (ret == -ENOENT)
-                       rec->errors |= I_ERR_NO_ORPHAN_ITEM;
-       }
+       if (rec->nlink == 0)
+               rec->errors |= I_ERR_NO_ORPHAN_ITEM;
        maybe_free_inode_rec(&active_node->inode_cache, rec);
        return 0;
 }
@@ -443,10 +473,9 @@ static int add_inode_backref(struct cache_tree *inode_cache,
 }
 
 static int merge_inode_recs(struct inode_record *src, struct inode_record *dst,
-                           struct shared_node *dst_node)
+                           struct cache_tree *dst_cache)
 {
        struct inode_backref *backref;
-       struct cache_tree *dst_cache = &dst_node->inode_cache;
 
        dst->merging = 1;
        list_for_each_entry(backref, &src->backrefs, list) {
@@ -510,14 +539,8 @@ static int merge_inode_recs(struct inode_record *src, struct inode_record *dst,
                        dst->errors |= I_ERR_DUP_INODE_ITEM;
                }
        }
-
-       if (src->checked) {
-               dst->checked = 1;
-               if (dst_node->current == dst)
-                       dst_node->current = NULL;
-       }
        dst->merging = 0;
-       maybe_free_inode_rec(dst_cache, dst);
+
        return 0;
 }
 
@@ -537,8 +560,9 @@ static int splice_shared_node(struct shared_node *src_node,
        if (src_node->current)
                current_ino = src_node->current->ino;
 
-       src = &src_node->inode_cache;
-       dst = &dst_node->inode_cache;
+       src = &src_node->root_cache;
+       dst = &dst_node->root_cache;
+again:
        cache = find_first_cache_extent(src, 0);
        while (cache) {
                node = container_of(cache, struct ptr_node, cache);
@@ -557,14 +581,28 @@ static int splice_shared_node(struct shared_node *src_node,
                }
                ret = insert_existing_cache_extent(dst, &ins->cache);
                if (ret == -EEXIST) {
+                       WARN_ON(src == &src_node->root_cache);
                        conflict = get_inode_rec(dst, rec->ino, 1);
-                       merge_inode_recs(rec, conflict, dst_node);
+                       merge_inode_recs(rec, conflict, dst);
+                       if (rec->checked) {
+                               conflict->checked = 1;
+                               if (dst_node->current == conflict)
+                                       dst_node->current = NULL;
+                       }
+                       maybe_free_inode_rec(dst, conflict);
                        free_inode_rec(rec);
                        free(ins);
                } else {
                        BUG_ON(ret);
                }
        }
+
+       if (src == &src_node->root_cache) {
+               src = &src_node->inode_cache;
+               dst = &dst_node->inode_cache;
+               goto again;
+       }
+
        if (current_ino > 0 && (!dst_node->current ||
            current_ino > dst_node->current->ino)) {
                if (dst_node->current) {
@@ -616,6 +654,7 @@ static int add_shared_node(struct cache_tree *shared, u64 bytenr, u32 refs)
        node = calloc(1, sizeof(*node));
        node->cache.start = bytenr;
        node->cache.size = 1;
+       cache_tree_init(&node->root_cache);
        cache_tree_init(&node->inode_cache);
        node->refs = refs;
 
@@ -646,6 +685,7 @@ static int enter_shared_node(struct btrfs_root *root, u64 bytenr, u32 refs,
        if (wc->root_level == wc->active_node &&
            btrfs_root_refs(&root->root_item) == 0) {
                if (--node->refs == 0) {
+                       free_inode_recs(&node->root_cache);
                        free_inode_recs(&node->inode_cache);
                        remove_cache_extent(&wc->shared, &node->cache);
                        free(node);
@@ -708,10 +748,12 @@ static int process_dir_item(struct extent_buffer *eb,
        int filetype;
        struct btrfs_dir_item *di;
        struct inode_record *rec;
+       struct cache_tree *root_cache;
        struct cache_tree *inode_cache;
        struct btrfs_key location;
        char namebuf[BTRFS_NAME_LEN];
 
+       root_cache = &active_node->root_cache;
        inode_cache = &active_node->inode_cache;
        rec = active_node->current;
        rec->found_dir_item = 1;
@@ -740,7 +782,9 @@ static int process_dir_item(struct extent_buffer *eb,
                                          key->objectid, key->offset, namebuf,
                                          len, filetype, key->type, error);
                } else if (location.type == BTRFS_ROOT_ITEM_KEY) {
-                       /* fixme: check root back & forward references */
+                       add_inode_backref(root_cache, location.objectid,
+                                         key->objectid, key->offset, namebuf,
+                                         len, filetype, key->type, error);
                } else {
                        fprintf(stderr, "warning line %d\n", __LINE__);
                }
@@ -977,8 +1021,7 @@ static int process_one_leaf(struct btrfs_root *root, struct extent_buffer *eb,
                        ret = process_inode_ref(eb, i, &key, active_node);
                        break;
                case BTRFS_INODE_ITEM_KEY:
-                       ret = process_inode_item(root, eb, i, &key,
-                                                active_node);
+                       ret = process_inode_item(eb, i, &key, active_node);
                        break;
                case BTRFS_EXTENT_DATA_KEY:
                        ret = process_file_extent(root, eb, i, &key,
@@ -1176,13 +1219,23 @@ static int check_inode_recs(struct btrfs_root *root,
                node = container_of(cache, struct ptr_node, cache);
                rec = node->data;
                remove_cache_extent(inode_cache, &node->cache);
+               free(node);
                if (rec->ino == root_dirid ||
                    rec->ino == BTRFS_ORPHAN_OBJECTID) {
-                       free(node);
                        free_inode_rec(rec);
                        continue;
                }
 
+               if (rec->errors & I_ERR_NO_ORPHAN_ITEM) {
+                       ret = check_orphan_item(root, rec->ino);
+                       if (ret == 0)
+                               rec->errors &= ~I_ERR_NO_ORPHAN_ITEM;
+                       if (can_free_inode_rec(rec)) {
+                               free_inode_rec(rec);
+                               continue;
+                       }
+               }
+
                error++;
                if (!rec->found_inode_item)
                        rec->errors |= I_ERR_NO_INODE_ITEM;
@@ -1205,13 +1258,314 @@ static int check_inode_recs(struct btrfs_root *root,
                                backref->namelen, backref->name,
                                backref->filetype, backref->errors);
                }
-               free(node);
                free_inode_rec(rec);
        }
        return (error > 0) ? -1 : 0;
 }
 
+static struct root_record *get_root_rec(struct cache_tree *root_cache,
+                                       u64 objectid)
+{
+       struct cache_extent *cache;
+       struct root_record *rec = NULL;
+       int ret;
+
+       cache = find_cache_extent(root_cache, objectid, 1);
+       if (cache) {
+               rec = container_of(cache, struct root_record, cache);
+       } else {
+               rec = calloc(1, sizeof(*rec));
+               rec->objectid = objectid;
+               INIT_LIST_HEAD(&rec->backrefs);
+               rec->cache.start = objectid;
+               rec->cache.size = 1;
+
+               ret = insert_existing_cache_extent(root_cache, &rec->cache);
+               BUG_ON(ret);
+       }
+       return rec;
+}
+
+static struct root_backref *get_root_backref(struct root_record *rec,
+                                            u64 ref_root, u64 dir, u64 index,
+                                            const char *name, int namelen)
+{
+       struct root_backref *backref;
+
+       list_for_each_entry(backref, &rec->backrefs, list) {
+               if (backref->ref_root != ref_root || backref->dir != dir ||
+                   backref->namelen != namelen)
+                       continue;
+               if (memcmp(name, backref->name, namelen))
+                       continue;
+               return backref;
+       }
+
+       backref = malloc(sizeof(*backref) + namelen + 1);
+       memset(backref, 0, sizeof(*backref));
+       backref->ref_root = ref_root;
+       backref->dir = dir;
+       backref->index = index;
+       backref->namelen = namelen;
+       memcpy(backref->name, name, namelen);
+       backref->name[namelen] = '\0';
+       list_add_tail(&backref->list, &rec->backrefs);
+       return backref;
+}
+
+static void free_root_recs(struct cache_tree *root_cache)
+{
+       struct cache_extent *cache;
+       struct root_record *rec;
+       struct root_backref *backref;
+
+       while (1) {
+               cache = find_first_cache_extent(root_cache, 0);
+               if (!cache)
+                       break;
+               rec = container_of(cache, struct root_record, cache);
+               remove_cache_extent(root_cache, &rec->cache);
+
+               while (!list_empty(&rec->backrefs)) {
+                       backref = list_entry(rec->backrefs.next,
+                                            struct root_backref, list);
+                       list_del(&backref->list);
+                       free(backref);
+               }
+               kfree(rec);
+       }
+}
+
+static int add_root_backref(struct cache_tree *root_cache,
+                           u64 root_id, u64 ref_root, u64 dir, u64 index,
+                           const char *name, int namelen,
+                           int item_type, int errors)
+{
+       struct root_record *rec;
+       struct root_backref *backref;
+
+       rec = get_root_rec(root_cache, root_id);
+       backref = get_root_backref(rec, ref_root, dir, index, name, namelen);
+
+       backref->errors |= errors;
+
+       if (item_type != BTRFS_DIR_ITEM_KEY) {
+               if (backref->found_dir_index || backref->found_back_ref ||
+                   backref->found_forward_ref) {
+                       if (backref->index != index)
+                               backref->errors |= REF_ERR_INDEX_UNMATCH;
+               } else {
+                       backref->index = index;
+               }
+       }
+
+       if (item_type == BTRFS_DIR_ITEM_KEY) {
+               backref->found_dir_item = 1;
+               backref->reachable = 1;
+               rec->found_ref++;
+       } else if (item_type == BTRFS_DIR_INDEX_KEY) {
+               backref->found_dir_index = 1;
+       } else if (item_type == BTRFS_ROOT_REF_KEY) {
+               if (backref->found_forward_ref)
+                       backref->errors |= REF_ERR_DUP_ROOT_REF;
+               backref->found_forward_ref = 1;
+       } else if (item_type == BTRFS_ROOT_BACKREF_KEY) {
+               if (backref->found_back_ref)
+                       backref->errors |= REF_ERR_DUP_ROOT_BACKREF;
+               backref->found_back_ref = 1;
+       } else {
+               BUG_ON(1);
+       }
+
+       return 0;
+}
+
+static int merge_root_recs(struct btrfs_root *root,
+                          struct cache_tree *src_cache,
+                          struct cache_tree *dst_cache)
+{
+       struct cache_extent *cache;
+       struct ptr_node *node;
+       struct inode_record *rec;
+       struct inode_backref *backref;
+
+       if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
+               free_inode_recs(src_cache);
+               return 0;
+       }
+
+       while (1) {
+               cache = find_first_cache_extent(src_cache, 0);
+               if (!cache)
+                       break;
+               node = container_of(cache, struct ptr_node, cache);
+               rec = node->data;
+               remove_cache_extent(src_cache, &node->cache);
+               free(node);
+
+               list_for_each_entry(backref, &rec->backrefs, list) {
+                       BUG_ON(backref->found_inode_ref);
+                       if (backref->found_dir_item)
+                               add_root_backref(dst_cache, rec->ino,
+                                       root->root_key.objectid, backref->dir,
+                                       backref->index, backref->name,
+                                       backref->namelen, BTRFS_DIR_ITEM_KEY,
+                                       backref->errors);
+                       if (backref->found_dir_index)
+                               add_root_backref(dst_cache, rec->ino,
+                                       root->root_key.objectid, backref->dir,
+                                       backref->index, backref->name,
+                                       backref->namelen, BTRFS_DIR_INDEX_KEY,
+                                       backref->errors);
+               }
+               free_inode_rec(rec);
+       }
+       return 0;
+}
+
+static int check_root_refs(struct btrfs_root *root,
+                          struct cache_tree *root_cache)
+{
+       struct root_record *rec;
+       struct root_record *ref_root;
+       struct root_backref *backref;
+       struct cache_extent *cache;
+       int loop = 1;
+       int ret;
+       int error;
+       int errors = 0;
+
+       rec = get_root_rec(root_cache, BTRFS_FS_TREE_OBJECTID);
+       rec->found_ref = 1;
+
+       /* fixme: this can not detect circular references */
+       while (loop) {
+               loop = 0;
+               cache = find_first_cache_extent(root_cache, 0);
+               while (1) {
+                       if (!cache)
+                               break;
+                       rec = container_of(cache, struct root_record, cache);
+                       cache = next_cache_extent(cache);
+
+                       if (rec->found_ref == 0)
+                               continue;
+
+                       list_for_each_entry(backref, &rec->backrefs, list) {
+                               if (!backref->reachable)
+                                       continue;
+
+                               ref_root = get_root_rec(root_cache,
+                                                       backref->ref_root);
+                               if (ref_root->found_ref > 0)
+                                       continue;
+
+                               backref->reachable = 0;
+                               rec->found_ref--;
+                               if (rec->found_ref == 0)
+                                       loop = 1;
+                       }
+               }
+       }
+
+       cache = find_first_cache_extent(root_cache, 0);
+       while (1) {
+               if (!cache)
+                       break;
+               rec = container_of(cache, struct root_record, cache);
+               cache = next_cache_extent(cache);
+
+               if (rec->found_ref == 0 &&
+                   rec->objectid >= BTRFS_FIRST_FREE_OBJECTID &&
+                   rec->objectid <= BTRFS_LAST_FREE_OBJECTID) {
+                       ret = check_orphan_item(root->fs_info->tree_root,
+                                               rec->objectid);
+                       if (ret == 0)
+                               continue;
+                       errors++;
+                       fprintf(stderr, "fs tree %llu not referenced\n",
+                               (unsigned long long)rec->objectid);
+               }
+
+               error = 0;
+               if (rec->found_ref > 0 && !rec->found_root_item)
+                       error = 1;
+               list_for_each_entry(backref, &rec->backrefs, list) {
+                       if (!backref->found_dir_item)
+                               backref->errors |= REF_ERR_NO_DIR_ITEM;
+                       if (!backref->found_dir_index)
+                               backref->errors |= REF_ERR_NO_DIR_INDEX;
+                       if (!backref->found_back_ref)
+                               backref->errors |= REF_ERR_NO_ROOT_BACKREF;
+                       if (!backref->found_forward_ref)
+                               backref->errors |= REF_ERR_NO_ROOT_REF;
+                       if (backref->reachable && backref->errors)
+                               error = 1;
+               }
+               if (!error)
+                       continue;
+
+               errors++;
+               fprintf(stderr, "fs tree %llu refs %u %s\n",
+                       (unsigned long long)rec->objectid, rec->found_ref,
+                        rec->found_root_item ? "" : "not found");
+
+               list_for_each_entry(backref, &rec->backrefs, list) {
+                       if (!backref->reachable)
+                               continue;
+                       if (!backref->errors && rec->found_root_item)
+                               continue;
+                       fprintf(stderr, "\tunresolved ref root %llu dir %llu"
+                               " index %llu namelen %u name %s error %x\n",
+                               (unsigned long long)backref->ref_root,
+                               (unsigned long long)backref->dir,
+                               (unsigned long long)backref->index,
+                               backref->namelen, backref->name,
+                               backref->errors);
+               }
+       }
+       return errors > 0 ? 1 : 0;
+}
+
+static int process_root_ref(struct extent_buffer *eb, int slot,
+                           struct btrfs_key *key,
+                           struct cache_tree *root_cache)
+{
+       u64 dirid;
+       u64 index;
+       u32 len;
+       u32 name_len;
+       struct btrfs_root_ref *ref;
+       char namebuf[BTRFS_NAME_LEN];
+       int error;
+
+       ref = btrfs_item_ptr(eb, slot, struct btrfs_root_ref);
+
+       dirid = btrfs_root_ref_dirid(eb, ref);
+       index = btrfs_root_ref_sequence(eb, ref);
+       name_len = btrfs_root_ref_name_len(eb, ref);
+
+       if (name_len <= BTRFS_NAME_LEN) {
+               len = name_len;
+               error = 0;
+       } else {
+               len = BTRFS_NAME_LEN;
+               error = REF_ERR_NAME_TOO_LONG;
+       }
+       read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
+
+       if (key->type == BTRFS_ROOT_REF_KEY) {
+               add_root_backref(root_cache, key->offset, key->objectid, dirid,
+                                index, namebuf, len, key->type, error);
+       } else {
+               add_root_backref(root_cache, key->objectid, key->offset, dirid,
+                                index, namebuf, len, key->type, error);
+       }
+       return 0;
+}
+
 static int check_fs_root(struct btrfs_root *root,
+                        struct cache_tree *root_cache,
                         struct walk_control *wc)
 {
        int ret = 0;
@@ -1219,10 +1573,18 @@ static int check_fs_root(struct btrfs_root *root,
        int level;
        struct btrfs_path path;
        struct shared_node root_node;
+       struct root_record *rec;
        struct btrfs_root_item *root_item = &root->root_item;
 
+       if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
+               rec = get_root_rec(root_cache, root->root_key.objectid);
+               if (btrfs_root_refs(root_item) > 0)
+                       rec->found_root_item = 1;
+       }
+
        btrfs_init_path(&path);
        memset(&root_node, 0, sizeof(root_node));
+       cache_tree_init(&root_node.root_cache);
        cache_tree_init(&root_node.inode_cache);
 
        level = btrfs_header_level(root->node);
@@ -1266,6 +1628,8 @@ static int check_fs_root(struct btrfs_root *root,
        }
        btrfs_release_path(root, &path);
 
+       merge_root_recs(root, &root_node.root_cache, root_cache);
+
        if (root_node.current) {
                root_node.current->checked = 1;
                maybe_free_inode_rec(&root_node.inode_cache,
@@ -1280,13 +1644,15 @@ static int fs_root_objectid(u64 objectid)
 {
        if (objectid == BTRFS_FS_TREE_OBJECTID ||
            objectid == BTRFS_TREE_RELOC_OBJECTID ||
+           objectid == BTRFS_DATA_RELOC_TREE_OBJECTID ||
            (objectid >= BTRFS_FIRST_FREE_OBJECTID &&
-            objectid < BTRFS_LAST_FREE_OBJECTID))
+            objectid <= BTRFS_LAST_FREE_OBJECTID))
                return 1;
        return 0;
 }
 
-static int check_fs_roots(struct btrfs_root *root)
+static int check_fs_roots(struct btrfs_root *root,
+                         struct cache_tree *root_cache)
 {
        struct btrfs_path path;
        struct btrfs_key key;
@@ -1319,10 +1685,14 @@ static int check_fs_roots(struct btrfs_root *root)
                    fs_root_objectid(key.objectid)) {
                        tmp_root = btrfs_read_fs_root_no_cache(root->fs_info,
                                                               &key);
-                       ret = check_fs_root(tmp_root, &wc);
+                       ret = check_fs_root(tmp_root, root_cache, &wc);
                        if (ret)
                                err = 1;
                        btrfs_free_fs_root(root->fs_info, tmp_root);
+               } else if (key.type == BTRFS_ROOT_REF_KEY ||
+                          key.type == BTRFS_ROOT_BACKREF_KEY) {
+                       process_root_ref(leaf, path.slots[0], &key,
+                                        root_cache);
                }
                path.slots[0]++;
        }
@@ -1895,7 +2265,6 @@ static int add_data_backref(struct cache_tree *extent_cache, u64 bytenr,
        return 0;
 }
 
-
 static int add_pending(struct cache_tree *pending,
                       struct cache_tree *seen, u64 bytenr, u32 size)
 {
@@ -2443,6 +2812,7 @@ static void print_usage(void)
 
 int main(int ac, char **av)
 {
+       struct cache_tree root_cache;
        struct btrfs_root *root;
        int ret;
 
@@ -2450,6 +2820,7 @@ int main(int ac, char **av)
                print_usage();
 
        radix_tree_init();
+       cache_tree_init(&root_cache);
        root = open_ctree(av[1], 0, 0);
 
        if (root == NULL)
@@ -2458,10 +2829,15 @@ int main(int ac, char **av)
        ret = check_extents(root);
        if (ret)
                goto out;
-       ret = check_fs_roots(root);
+       ret = check_fs_roots(root, &root_cache);
+       if (ret)
+               goto out;
 
+       ret = check_root_refs(root, &root_cache);
 out:
+       free_root_recs(&root_cache);
        close_ctree(root);
+
        if (found_old_backref) {
                /*
                 * there was a disk format change when mixed