static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, const char *tgtdev_name, u64 srcdevid, const char *srcdev_name, int read_src) { struct btrfs_root *root = fs_info->dev_root; struct btrfs_trans_handle *trans; struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; int ret; struct btrfs_device *tgt_device = NULL; struct btrfs_device *src_device = NULL; bool need_unlock; src_device = btrfs_find_device_by_devspec(fs_info, srcdevid, srcdev_name); if (IS_ERR(src_device)) return PTR_ERR(src_device); if (btrfs_pinned_by_swapfile(fs_info, src_device)) { btrfs_warn_in_rcu(fs_info, "cannot replace device %s (devid %llu) due to active swapfile", btrfs_dev_name(src_device), src_device->devid); return -ETXTBSY; } ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name, src_device, &tgt_device); if (ret) return ret; /* * Here we commit the transaction to make sure commit_total_bytes * of all the devices are updated. */ trans = btrfs_attach_transaction(root); if (!IS_ERR(trans)) { ret = btrfs_commit_transaction(trans); if (ret) return ret; } else if (PTR_ERR(trans) != -ENOENT) { return PTR_ERR(trans); } need_unlock = true; down_write(&dev_replace->rwsem); switch (dev_replace->replace_state) { case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: break; case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: ASSERT(0); ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED; goto leave; } dev_replace->cont_reading_from_srcdev_mode = read_src; WARN_ON(!src_device); dev_replace->srcdev = src_device; dev_replace->tgtdev = tgt_device; btrfs_info_in_rcu(fs_info, "dev_replace from %s (devid %llu) to %s started", btrfs_dev_name(src_device), src_device->devid, rcu_str_deref(tgt_device->name)); /* * from now on, the writes to the srcdev are all duplicated to * go to the tgtdev as well (refer to btrfs_map_block()). */ dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; dev_replace->time_started = ktime_get_real_seconds(); dev_replace->cursor_left = 0; dev_replace->committed_cursor_left = 0; dev_replace->cursor_left_last_write_of_item = 0; dev_replace->cursor_right = 0; dev_replace->is_valid = 1; dev_replace->item_needs_writeback = 1; atomic64_set(&dev_replace->num_write_errors, 0); atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); up_write(&dev_replace->rwsem); need_unlock = false; ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device); if (ret) btrfs_err(fs_info, "kobj add dev failed %d", ret); btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); /* force writing the updated state information to disk */ trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); need_unlock = true; down_write(&dev_replace->rwsem); dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED; dev_replace->srcdev = NULL; dev_replace->tgtdev = NULL; goto leave; } ret = btrfs_commit_transaction(trans); WARN_ON(ret); /* the disk copy procedure reuses the scrub code */ ret = btrfs_scrub_dev(fs_info, src_device->devid, 0, btrfs_device_get_total_bytes(src_device), &dev_replace->scrub_progress, 0, 1); ret = btrfs_dev_replace_finishing(fs_info, ret); if (ret == -EINPROGRESS) { ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS; } else if (ret != -ECANCELED) { WARN_ON(ret); } return ret; leave: if (need_unlock) up_write(&dev_replace->rwsem); btrfs_destroy_dev_replace_tgtdev(tgt_device); return ret; }
int btrfs_dev_replace_start(struct btrfs_root *root, char *tgtdev_name, u64 srcdevid, char *srcdev_name, int read_src) { struct btrfs_trans_handle *trans; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; int ret; struct btrfs_device *tgt_device = NULL; struct btrfs_device *src_device = NULL; /* the disk copy procedure reuses the scrub code */ mutex_lock(&fs_info->volume_mutex); ret = btrfs_find_device_by_devspec(root, srcdevid, srcdev_name, &src_device); if (ret) { mutex_unlock(&fs_info->volume_mutex); return ret; } ret = btrfs_init_dev_replace_tgtdev(root, tgtdev_name, src_device, &tgt_device); mutex_unlock(&fs_info->volume_mutex); if (ret) return ret; /* * Here we commit the transaction to make sure commit_total_bytes * of all the devices are updated. */ trans = btrfs_attach_transaction(root); if (!IS_ERR(trans)) { ret = btrfs_commit_transaction(trans, root); if (ret) return ret; } else if (PTR_ERR(trans) != -ENOENT) { return PTR_ERR(trans); } btrfs_dev_replace_lock(dev_replace, 1); switch (dev_replace->replace_state) { case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: break; case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED; goto leave; } dev_replace->cont_reading_from_srcdev_mode = read_src; WARN_ON(!src_device); dev_replace->srcdev = src_device; WARN_ON(!tgt_device); dev_replace->tgtdev = tgt_device; btrfs_info_in_rcu(fs_info, "dev_replace from %s (devid %llu) to %s started", src_device->missing ? "<missing disk>" : rcu_str_deref(src_device->name), src_device->devid, rcu_str_deref(tgt_device->name)); /* * from now on, the writes to the srcdev are all duplicated to * go to the tgtdev as well (refer to btrfs_map_block()). */ dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; dev_replace->time_started = get_seconds(); dev_replace->cursor_left = 0; dev_replace->committed_cursor_left = 0; dev_replace->cursor_left_last_write_of_item = 0; dev_replace->cursor_right = 0; dev_replace->is_valid = 1; dev_replace->item_needs_writeback = 1; atomic64_set(&dev_replace->num_write_errors, 0); atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); btrfs_dev_replace_unlock(dev_replace, 1); ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device); if (ret) btrfs_err(fs_info, "kobj add dev failed %d\n", ret); btrfs_wait_ordered_roots(root->fs_info, -1, 0, (u64)-1); /* force writing the updated state information to disk */ trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); btrfs_dev_replace_lock(dev_replace, 1); goto leave; } ret = btrfs_commit_transaction(trans, root); WARN_ON(ret); /* the disk copy procedure reuses the scrub code */ ret = btrfs_scrub_dev(fs_info, src_device->devid, 0, btrfs_device_get_total_bytes(src_device), &dev_replace->scrub_progress, 0, 1); ret = btrfs_dev_replace_finishing(fs_info, ret); if (ret == -EINPROGRESS) { ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS; } else { WARN_ON(ret); } return ret; leave: dev_replace->srcdev = NULL; dev_replace->tgtdev = NULL; btrfs_dev_replace_unlock(dev_replace, 1); btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device); return ret; }