#include "print-tree.h"
/*
- * returns 0 on finding something, 1 if no more roots are there
- * and < 0 on error
+ * search forward for a root, starting with objectid 'search_start'
+ * if a root key is found, the objectid we find is filled into 'found_objectid'
+ * and 0 is returned. < 0 is returned on error, 1 if there is nothing
+ * left in the tree.
*/
int btrfs_search_root(struct btrfs_root *root, u64 search_start,
u64 *found_objectid)
return ret;
}
+/*
+ * lookup the root with the highest offset for a given objectid. The key we do
+ * find is copied into 'key'. If we find something return 0, otherwise 1, < 0
+ * on error.
+ */
int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
struct btrfs_root_item *item, struct btrfs_key *key)
{
int slot;
search_key.objectid = objectid;
- search_key.type = (u8)-1;
+ search_key.type = BTRFS_ROOT_ITEM_KEY;
search_key.offset = (u64)-1;
path = btrfs_alloc_path();
return ret;
}
+/*
+ * copy the data in 'item' into the btree
+ */
int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_key *key, struct btrfs_root_item
*item)
if (ret != 0) {
btrfs_print_leaf(root, path->nodes[0]);
- printk("unable to update root key %Lu %u %Lu\n",
- key->objectid, key->type, key->offset);
+ printk(KERN_CRIT "unable to update root key %llu %u %llu\n",
+ (unsigned long long)key->objectid, key->type,
+ (unsigned long long)key->offset);
BUG_ON(1);
}
return ret;
}
+/*
+ * at mount time we want to find all the old transaction snapshots that were in
+ * the process of being deleted if we crashed. This is any root item with an
+ * offset lower than the latest root. They need to be queued for deletion to
+ * finish what was happening when we crashed.
+ */
int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid,
struct btrfs_root *latest)
{
struct btrfs_item *item;
struct btrfs_root_item *ri;
struct btrfs_key key;
+ struct btrfs_key found_key;
struct btrfs_path *path;
int ret;
u32 nritems;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
+
+again:
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto err;
- while(1) {
+ while (1) {
leaf = path->nodes[0];
nritems = btrfs_header_nritems(leaf);
slot = path->slots[0];
if (btrfs_disk_root_refs(leaf, ri) != 0)
goto next;
- dead_root = btrfs_read_fs_root_no_radix(root->fs_info, &key);
+ memcpy(&found_key, &key, sizeof(key));
+ key.offset++;
+ btrfs_release_path(root, path);
+ dead_root =
+ btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
+ &found_key);
if (IS_ERR(dead_root)) {
ret = PTR_ERR(dead_root);
goto err;
}
- ret = btrfs_add_dead_root(dead_root, latest,
- &root->fs_info->dead_roots);
+ if (objectid == BTRFS_TREE_RELOC_OBJECTID)
+ ret = btrfs_add_dead_reloc_root(dead_root);
+ else
+ ret = btrfs_add_dead_root(dead_root, latest);
if (ret)
goto err;
+ goto again;
next:
slot++;
path->slots[0]++;
return ret;
}
+/* drop the root item for 'key' from 'root' */
int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct btrfs_key *key)
{
ret = btrfs_search_slot(trans, root, key, path, -1, 1);
if (ret < 0)
goto out;
- if (ret) {
-btrfs_print_leaf(root, path->nodes[0]);
-printk("failed to del %Lu %u %Lu\n", key->objectid, key->type, key->offset);
- }
BUG_ON(ret != 0);
leaf = path->nodes[0];
ri = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_item);
btrfs_free_path(path);
return ret;
}
+
+#if 0 /* this will get used when snapshot deletion is implemented */
+int btrfs_del_root_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *tree_root,
+ u64 root_id, u8 type, u64 ref_id)
+{
+ struct btrfs_key key;
+ int ret;
+ struct btrfs_path *path;
+
+ path = btrfs_alloc_path();
+
+ key.objectid = root_id;
+ key.type = type;
+ key.offset = ref_id;
+
+ ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
+ BUG_ON(ret);
+
+ ret = btrfs_del_item(trans, tree_root, path);
+ BUG_ON(ret);
+
+ btrfs_free_path(path);
+ return ret;
+}
+#endif
+
+int btrfs_find_root_ref(struct btrfs_root *tree_root,
+ struct btrfs_path *path,
+ u64 root_id, u64 ref_id)
+{
+ struct btrfs_key key;
+ int ret;
+
+ key.objectid = root_id;
+ key.type = BTRFS_ROOT_REF_KEY;
+ key.offset = ref_id;
+
+ ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
+ return ret;
+}
+
+
+/*
+ * add a btrfs_root_ref item. type is either BTRFS_ROOT_REF_KEY
+ * or BTRFS_ROOT_BACKREF_KEY.
+ *
+ * The dirid, sequence, name and name_len refer to the directory entry
+ * that is referencing the root.
+ *
+ * For a forward ref, the root_id is the id of the tree referencing
+ * the root and ref_id is the id of the subvol or snapshot.
+ *
+ * For a back ref the root_id is the id of the subvol or snapshot and
+ * ref_id is the id of the tree referencing it.
+ */
+int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *tree_root,
+ u64 root_id, u8 type, u64 ref_id,
+ u64 dirid, u64 sequence,
+ const char *name, int name_len)
+{
+ struct btrfs_key key;
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_root_ref *ref;
+ struct extent_buffer *leaf;
+ unsigned long ptr;
+
+
+ path = btrfs_alloc_path();
+
+ key.objectid = root_id;
+ key.type = type;
+ key.offset = ref_id;
+
+ ret = btrfs_insert_empty_item(trans, tree_root, path, &key,
+ sizeof(*ref) + name_len);
+ BUG_ON(ret);
+
+ leaf = path->nodes[0];
+ ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
+ btrfs_set_root_ref_dirid(leaf, ref, dirid);
+ btrfs_set_root_ref_sequence(leaf, ref, sequence);
+ btrfs_set_root_ref_name_len(leaf, ref, name_len);
+ ptr = (unsigned long)(ref + 1);
+ write_extent_buffer(leaf, name, ptr, name_len);
+ btrfs_mark_buffer_dirty(leaf);
+
+ btrfs_free_path(path);
+ return ret;
+}
git.openpandora.org / pandora-kernel.git / blobdiff