int drbd_adm_resize()

in drbd/drbd_nl.c [2831:2966]
117 lines of code
29 McCabe index (conditional complexity)

int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
{
	struct drbd_config_context adm_ctx;
	struct disk_conf *old_disk_conf, *new_disk_conf = NULL;
	struct resize_parms rs;
	struct drbd_device *device;
	enum drbd_ret_code retcode;
	enum determine_dev_size dd;
	bool change_al_layout = false;
	enum dds_flags ddsf;
	sector_t u_size;
	int err;

	retcode = drbd_adm_prepare(&adm_ctx, skb, info, DRBD_ADM_NEED_MINOR);
	if (!adm_ctx.reply_skb)
		return retcode;
	if (retcode != NO_ERROR)
		goto finish;

	mutex_lock(&adm_ctx.resource->adm_mutex);
	device = adm_ctx.device;
	if (!get_ldev(device)) {
		retcode = ERR_NO_DISK;
		goto fail;
	}

	memset(&rs, 0, sizeof(struct resize_parms));
	rs.al_stripes = device->ldev->md.al_stripes;
	rs.al_stripe_size = device->ldev->md.al_stripe_size_4k * 4;
	if (info->attrs[DRBD_NLA_RESIZE_PARMS]) {
		err = resize_parms_from_attrs(&rs, info);
		if (err) {
			retcode = ERR_MANDATORY_TAG;
			drbd_msg_put_info(adm_ctx.reply_skb, from_attrs_err_to_txt(err));
			goto fail_ldev;
		}
	}

	if (device->state.conn > C_CONNECTED) {
		retcode = ERR_RESIZE_RESYNC;
		goto fail_ldev;
	}

	if (device->state.role == R_SECONDARY &&
	    device->state.peer == R_SECONDARY) {
		retcode = ERR_NO_PRIMARY;
		goto fail_ldev;
	}

	if (rs.no_resync && first_peer_device(device)->connection->agreed_pro_version < 93) {
		retcode = ERR_NEED_APV_93;
		goto fail_ldev;
	}

	rcu_read_lock();
	u_size = rcu_dereference(device->ldev->disk_conf)->disk_size;
	rcu_read_unlock();
	if (u_size != (sector_t)rs.resize_size) {
		new_disk_conf = kmalloc(sizeof(struct disk_conf), GFP_KERNEL);
		if (!new_disk_conf) {
			retcode = ERR_NOMEM;
			goto fail_ldev;
		}
	}

	if (device->ldev->md.al_stripes != rs.al_stripes ||
	    device->ldev->md.al_stripe_size_4k != rs.al_stripe_size / 4) {
		u32 al_size_k = rs.al_stripes * rs.al_stripe_size;

		if (al_size_k > (16 * 1024 * 1024)) {
			retcode = ERR_MD_LAYOUT_TOO_BIG;
			goto fail_ldev;
		}

		if (al_size_k < MD_32kB_SECT/2) {
			retcode = ERR_MD_LAYOUT_TOO_SMALL;
			goto fail_ldev;
		}

		if (device->state.conn != C_CONNECTED && !rs.resize_force) {
			retcode = ERR_MD_LAYOUT_CONNECTED;
			goto fail_ldev;
		}

		change_al_layout = true;
	}

	if (device->ldev->known_size != drbd_get_capacity(device->ldev->backing_bdev))
		device->ldev->known_size = drbd_get_capacity(device->ldev->backing_bdev);

	if (new_disk_conf) {
		mutex_lock(&device->resource->conf_update);
		old_disk_conf = device->ldev->disk_conf;
		*new_disk_conf = *old_disk_conf;
		new_disk_conf->disk_size = (sector_t)rs.resize_size;
		rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
		mutex_unlock(&device->resource->conf_update);
		synchronize_rcu();
		kfree(old_disk_conf);
		new_disk_conf = NULL;
	}

	ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
	dd = drbd_determine_dev_size(device, ddsf, change_al_layout ? &rs : NULL);
	drbd_md_sync(device);
	put_ldev(device);
	if (dd == DS_ERROR) {
		retcode = ERR_NOMEM_BITMAP;
		goto fail;
	} else if (dd == DS_ERROR_SPACE_MD) {
		retcode = ERR_MD_LAYOUT_NO_FIT;
		goto fail;
	} else if (dd == DS_ERROR_SHRINK) {
		retcode = ERR_IMPLICIT_SHRINK;
		goto fail;
	}

	if (device->state.conn == C_CONNECTED) {
		if (dd == DS_GREW)
			set_bit(RESIZE_PENDING, &device->flags);

		drbd_send_uuids(first_peer_device(device));
		drbd_send_sizes(first_peer_device(device), 1, ddsf);
	}

 fail:
	mutex_unlock(&adm_ctx.resource->adm_mutex);
 finish:
	drbd_adm_finish(&adm_ctx, info, retcode);
	return 0;

 fail_ldev:
	put_ldev(device);
	kfree(new_disk_conf);
	goto fail;
}