An SVM administrator could be restricted via 'Aggregate delegation' & 'max-volumes' options.
Aggregate Delegation : This allows "cluster Admin" to put restriction on 'SVMs'.
For example: With no "aggr delegation", SVM admin cannot create any volumes, they can only manage what is already provisioned. Further, you can also designate specific list of aggregates for SVM to work with.
As cluster admin:
You can first check, if there is any aggr-list given to that SVM:
::> vserver show -vserver <vserver> -fields aggr-list
That is not possible. Once you have designated a 'aggregate' to the SVM, SVM admin can use as much space as the aggregate holds, for the volume purpose. However, this is where alerting becomes handy.
Two key alerts : Aggregate Full and Aggregate Nearly Full thresholds, if set accordingly (depending upon the size of the Aggregate) percentile wise, "Gives you enough time to take corrective action if storage usage approaches the capacity that you do want SVM to cross".