diff --git a/src/api2/admin/datastore.rs b/src/api2/admin/datastore.rs
index e66e1c0b..c8e86b07 100644
--- a/src/api2/admin/datastore.rs
+++ b/src/api2/admin/datastore.rs
@@ -1804,6 +1804,7 @@ pub fn get_rrd_stats(
 
     let mut rrd_fields = vec![
         "total",
+        "available",
         "used",
         "read_ios",
         "read_bytes",
diff --git a/www/dashboard/DataStoreStatistics.js b/www/dashboard/DataStoreStatistics.js
index 38f7a2fe..0510fc7d 100644
--- a/www/dashboard/DataStoreStatistics.js
+++ b/www/dashboard/DataStoreStatistics.js
@@ -3,7 +3,12 @@ Ext.define('pbs-datastore-statistics', {
 
     fields: [
 	'store',
-	'total',
+	{
+	    name: 'total',
+	    calculate: function(data) {
+		return data.avail + data.used;
+	    },
+	},
 	'used',
 	'avail',
 	'estimated-full-date',
diff --git a/www/datastore/DataStoreListSummary.js b/www/datastore/DataStoreListSummary.js
index c7b67d56..bec0562d 100644
--- a/www/datastore/DataStoreListSummary.js
+++ b/www/datastore/DataStoreListSummary.js
@@ -52,10 +52,11 @@ Ext.define('PBS.datastore.DataStoreListSummary', {
 	    vm.set('maintenance', '');
 	}
 
-	let usage = statusData.used/statusData.total;
+	let total = statusData.avail + statusData.used;
+	let usage = statusData.used / total;
 	let usagetext = Ext.String.format(gettext('{0} of {1}'),
 	    Proxmox.Utils.format_size(statusData.used, true),
-	    Proxmox.Utils.format_size(statusData.total, true),
+	    Proxmox.Utils.format_size(total, true),
 	);
 
 	let usagePanel = me.lookup('usage');
diff --git a/www/datastore/Summary.js b/www/datastore/Summary.js
index 94be9559..d67e81cc 100644
--- a/www/datastore/Summary.js
+++ b/www/datastore/Summary.js
@@ -3,6 +3,20 @@ Ext.define('pve-rrd-datastore', {
     fields: [
 	'used',
 	'total',
+	{
+	    name: 'unpriv-total', // Can't resuse 'total' here as that creates a stack overflow
+	    calculate: function(data) {
+		let used = data.used;
+		let avail = data.available;
+
+		if (avail && used) {
+		    return avail + used;
+		}
+
+		return data.total;
+	    },
+	},
+	'available',
 	'read_ios',
 	'read_bytes',
 	'write_ios',
@@ -66,8 +80,8 @@ Ext.define('PBS.DataStoreInfo', {
 	    let vm = me.getViewModel();
 
 	    let counts = store.getById('counts').data.value;
-	    let total = store.getById('total').data.value;
 	    let used = store.getById('used').data.value;
+	    let total = store.getById('avail').data.value + used;
 
 	    let usage = Proxmox.Utils.render_size_usage(used, total, true);
 	    vm.set('usagetext', usage);
@@ -236,7 +250,7 @@ Ext.define('PBS.DataStoreSummary', {
 	{
 	    xtype: 'proxmoxRRDChart',
 	    title: gettext('Storage usage (bytes)'),
-	    fields: ['total', 'used'],
+	    fields: ['unpriv-total', 'used'],
 	    fieldTitles: [gettext('Total'), gettext('Storage usage')],
 	},
 	{