atomic_t mutually_exclusive_operation_running;
struct semaphore uuid_tree_rescan_sem;
+ unsigned int update_uuid_tree_gen:1;
};
/*
int btrfs_uuid_tree_rem(struct btrfs_trans_handle *trans,
struct btrfs_root *uuid_root, u8 *uuid, u8 type,
u64 subid);
+int btrfs_uuid_tree_iterate(struct btrfs_fs_info *fs_info,
+ int (*check_func)(struct btrfs_fs_info *, u8 *, u8,
+ u64));
/* dir-item.c */
int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
int err = -EINVAL;
int num_backups_tried = 0;
int backup_index = 0;
- bool create_uuid_tree = false;
+ bool create_uuid_tree;
+ bool check_uuid_tree;
tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info);
chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
if (ret != -ENOENT)
goto recovery_tree_root;
create_uuid_tree = true;
+ check_uuid_tree = false;
} else {
uuid_root->track_dirty = 1;
fs_info->uuid_root = uuid_root;
+ create_uuid_tree = false;
+ check_uuid_tree =
+ generation != btrfs_super_uuid_tree_generation(disk_super);
}
fs_info->generation = generation;
close_ctree(tree_root);
return ret;
}
+ } else if (check_uuid_tree) {
+ pr_info("btrfs: checking UUID tree\n");
+ ret = btrfs_check_uuid_tree(fs_info);
+ if (ret) {
+ pr_warn("btrfs: failed to check the UUID tree %d\n",
+ ret);
+ close_ctree(tree_root);
+ return ret;
+ }
+ } else {
+ fs_info->update_uuid_tree_gen = 1;
}
return 0;
super->root_level = root_item->level;
if (btrfs_test_opt(root, SPACE_CACHE))
super->cache_generation = root_item->generation;
- super->uuid_tree_generation = root_item->generation;
+ if (root->fs_info->update_uuid_tree_gen)
+ super->uuid_tree_generation = root_item->generation;
}
int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
btrfs_free_path(path);
return ret;
}
+
+static int btrfs_uuid_iter_rem(struct btrfs_root *uuid_root, u8 *uuid, u8 type,
+ u64 subid)
+{
+ struct btrfs_trans_handle *trans;
+ int ret;
+
+ /* 1 - for the uuid item */
+ trans = btrfs_start_transaction(uuid_root, 1);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out;
+ }
+
+ ret = btrfs_uuid_tree_rem(trans, uuid_root, uuid, type, subid);
+ btrfs_end_transaction(trans, uuid_root);
+
+out:
+ return ret;
+}
+
+int btrfs_uuid_tree_iterate(struct btrfs_fs_info *fs_info,
+ int (*check_func)(struct btrfs_fs_info *, u8 *, u8,
+ u64))
+{
+ struct btrfs_root *root = fs_info->uuid_root;
+ struct btrfs_key key;
+ struct btrfs_key max_key;
+ struct btrfs_path *path;
+ int ret = 0;
+ struct extent_buffer *leaf;
+ int slot;
+ u32 item_size;
+ unsigned long offset;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ key.objectid = 0;
+ key.type = 0;
+ key.offset = 0;
+ max_key.objectid = (u64)-1;
+ max_key.type = (u8)-1;
+ max_key.offset = (u64)-1;
+
+again_search_slot:
+ path->keep_locks = 1;
+ ret = btrfs_search_forward(root, &key, &max_key, path, 0);
+ if (ret) {
+ if (ret > 0)
+ ret = 0;
+ goto out;
+ }
+
+ while (1) {
+ cond_resched();
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+
+ if (key.type != BTRFS_UUID_KEY_SUBVOL &&
+ key.type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
+ goto skip;
+
+ offset = btrfs_item_ptr_offset(leaf, slot);
+ item_size = btrfs_item_size_nr(leaf, slot);
+ if (!IS_ALIGNED(item_size, sizeof(u64))) {
+ pr_warn("btrfs: uuid item with illegal size %lu!\n",
+ (unsigned long)item_size);
+ goto skip;
+ }
+ while (item_size) {
+ u8 uuid[BTRFS_UUID_SIZE];
+ __le64 subid_le;
+ u64 subid_cpu;
+
+ put_unaligned_le64(key.objectid, uuid);
+ put_unaligned_le64(key.offset, uuid + sizeof(u64));
+ read_extent_buffer(leaf, &subid_le, offset,
+ sizeof(subid_le));
+ subid_cpu = le64_to_cpu(subid_le);
+ ret = check_func(fs_info, uuid, key.type, subid_cpu);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ btrfs_release_path(path);
+ ret = btrfs_uuid_iter_rem(root, uuid, key.type,
+ subid_cpu);
+ if (ret == 0) {
+ /*
+ * this might look inefficient, but the
+ * justification is that it is an
+ * exception that check_func returns 1,
+ * and that in the regular case only one
+ * entry per UUID exists.
+ */
+ goto again_search_slot;
+ }
+ if (ret < 0 && ret != -ENOENT)
+ goto out;
+ }
+ item_size -= sizeof(subid_le);
+ offset += sizeof(subid_le);
+ }
+
+skip:
+ ret = btrfs_next_item(root, path);
+ if (ret == 0)
+ continue;
+ else if (ret > 0)
+ ret = 0;
+ break;
+ }
+
+out:
+ btrfs_free_path(path);
+ if (ret)
+ pr_warn("btrfs: btrfs_uuid_tree_iterate failed %d\n", ret);
+ return 0;
+}
btrfs_free_path(path);
if (ret)
pr_warn("btrfs: btrfs_uuid_scan_kthread failed %d\n", ret);
+ else
+ fs_info->update_uuid_tree_gen = 1;
up(&fs_info->uuid_tree_rescan_sem);
return 0;
}
+/*
+ * Callback for btrfs_uuid_tree_iterate().
+ * returns:
+ * 0 check succeeded, the entry is not outdated.
+ * < 0 if an error occured.
+ * > 0 if the check failed, which means the caller shall remove the entry.
+ */
+static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
+ u8 *uuid, u8 type, u64 subid)
+{
+ struct btrfs_key key;
+ int ret = 0;
+ struct btrfs_root *subvol_root;
+
+ if (type != BTRFS_UUID_KEY_SUBVOL &&
+ type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
+ goto out;
+
+ key.objectid = subid;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+ key.offset = (u64)-1;
+ subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
+ if (IS_ERR(subvol_root)) {
+ ret = PTR_ERR(subvol_root);
+ if (ret == -ENOENT)
+ ret = 1;
+ goto out;
+ }
+
+ switch (type) {
+ case BTRFS_UUID_KEY_SUBVOL:
+ if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
+ ret = 1;
+ break;
+ case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
+ if (memcmp(uuid, subvol_root->root_item.received_uuid,
+ BTRFS_UUID_SIZE))
+ ret = 1;
+ break;
+ }
+
+out:
+ return ret;
+}
+
+static int btrfs_uuid_rescan_kthread(void *data)
+{
+ struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
+ int ret;
+
+ /*
+ * 1st step is to iterate through the existing UUID tree and
+ * to delete all entries that contain outdated data.
+ * 2nd step is to add all missing entries to the UUID tree.
+ */
+ ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
+ if (ret < 0) {
+ pr_warn("btrfs: iterating uuid_tree failed %d\n", ret);
+ up(&fs_info->uuid_tree_rescan_sem);
+ return ret;
+ }
+ return btrfs_uuid_scan_kthread(data);
+}
+
int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
{
struct btrfs_trans_handle *trans;
down(&fs_info->uuid_tree_rescan_sem);
task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
if (IS_ERR(task)) {
+ /* fs_info->update_uuid_tree_gen remains 0 in all error case */
pr_warn("btrfs: failed to start uuid_scan task\n");
up(&fs_info->uuid_tree_rescan_sem);
return PTR_ERR(task);
return 0;
}
+int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
+{
+ struct task_struct *task;
+
+ down(&fs_info->uuid_tree_rescan_sem);
+ task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
+ if (IS_ERR(task)) {
+ /* fs_info->update_uuid_tree_gen remains 0 in all error case */
+ pr_warn("btrfs: failed to start uuid_rescan task\n");
+ up(&fs_info->uuid_tree_rescan_sem);
+ return PTR_ERR(task);
+ }
+
+ return 0;
+}
+
/*
* shrinking a device means finding all of the device extents past
* the new size, and then following the back refs to the chunks.
int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
+int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
int find_free_dev_extent(struct btrfs_trans_handle *trans,
struct btrfs_device *device, u64 num_bytes,