pool: allow negative step num in crush rule

The crush rules may have a negative step num.
Rook had assumed negative values were not possible,
but just had not been encountered previously in
a custom crush rule.

Signed-off-by: Travis Nielsen <tnielsen@redhat.com>
(cherry picked from commit b9188c793a)

pkg/daemon/ceph/client/crush.go

@@ -75,7 +75,7 @@ type ruleSpec struct {
 
 type stepSpec struct {
 	Operation string `json:"op"`
-	Number    uint   `json:"num"`
+	Number    int    `json:"num"`
 	Item      int    `json:"item"`
 	ItemName  string `json:"item_name"`
 	Type      string `json:"type"`

pkg/daemon/ceph/client/crush_rule.go

@@ -150,7 +150,7 @@ func buildTwoStepCrushSteps(pool cephv1.PoolSpec) []stepSpec {
 	// Step three
 	stepTakeSubFailureDomain := &stepSpec{
 		Operation: "chooseleaf_firstn",
-		Number:    pool.Replicated.ReplicasPerFailureDomain,
+		Number:    int(pool.Replicated.ReplicasPerFailureDomain),
 		Type:      pool.Replicated.SubFailureDomain,
 	}
 	steps = append(steps, *stepTakeSubFailureDomain)

pkg/daemon/ceph/client/crush_rule_test.go

@@ -56,7 +56,7 @@ func TestBuildCrushSteps(t *testing.T) {
 	assert.Equal(t, 4, len(steps))
 	assert.Equal(t, cephv1.DefaultCRUSHRoot, steps[0].ItemName)
 	assert.Equal(t, "datacenter", steps[1].Type)
-	assert.Equal(t, uint(2), steps[2].Number)
+	assert.Equal(t, 2, steps[2].Number)
 }
 
 func TestCompileCRUSHMap(t *testing.T) {