From dcd48a9ca1a008fb96803174e388528716237066 Mon Sep 17 00:00:00 2001
From: Eric Ernst <eric.ernst@intel.com>
Date: Sun, 2 Dec 2018 00:14:53 +0000
Subject: [PATCH] vc: capabilities: add capability flags for filesystem sharing

Not all hypervisors support filesystem sharing. Add capability flags to track
this. Since most hypervisor implementations in Kata *do* support this, the set
semantices are reversed (ie, set the flag if you do not support the feature).

Fixes: #1022

Signed-off-by: Eric Ernst <eric.ernst@intel.com>
Signed-off-by: Julio Montes <julio.montes@intel.com>
---
 virtcontainers/capabilities.go      |  9 +++++++++
 virtcontainers/capabilities_test.go | 14 ++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/virtcontainers/capabilities.go b/virtcontainers/capabilities.go
index 6eb34c3b81..72716ddb24 100644
--- a/virtcontainers/capabilities.go
+++ b/virtcontainers/capabilities.go
@@ -9,6 +9,7 @@ const (
 	blockDeviceSupport = 1 << iota
 	blockDeviceHotplugSupport
 	multiQueueSupport
+	fsSharingUnsupported
 )
 
 type capabilities struct {
@@ -47,3 +48,11 @@ func (caps *capabilities) isMultiQueueSupported() bool {
 func (caps *capabilities) setMultiQueueSupport() {
 	caps.flags |= multiQueueSupport
 }
+
+func (caps *capabilities) isFsSharingSupported() bool {
+	return caps.flags&fsSharingUnsupported == 0
+}
+
+func (caps *capabilities) setFsSharingUnsupported() {
+	caps.flags |= fsSharingUnsupported
+}
diff --git a/virtcontainers/capabilities_test.go b/virtcontainers/capabilities_test.go
index 91bde2fe55..3396989a85 100644
--- a/virtcontainers/capabilities_test.go
+++ b/virtcontainers/capabilities_test.go
@@ -34,3 +34,17 @@ func TestBlockDeviceHotplugCapability(t *testing.T) {
 		t.Fatal()
 	}
 }
+
+func TestFsSharingCapability(t *testing.T) {
+	var caps capabilities
+
+	if !caps.isFsSharingSupported() {
+		t.Fatal()
+	}
+
+	caps.setFsSharingUnsupported()
+
+	if caps.isFsSharingSupported() {
+		t.Fatal()
+	}
+}