feat: implement volume allocation and release in device registry

Signed-off-by: cheolho.kang <cheolho.kang@samsung.com>

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/kubernetes-csi/csi-lib-utils v0.13.0
 	golang.org/x/net v0.5.0
 	google.golang.org/grpc v1.51.0
+	k8s.io/apimachinery v0.26.0
 	k8s.io/klog/v2 v2.80.1
 	k8s.io/utils v0.0.0-20230209194617-a36077c30491
 )

go.sum

@@ -148,6 +148,8 @@ gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
+k8s.io/apimachinery v0.26.0 h1:1feANjElT7MvPqp0JT6F3Ss6TWDwmcjLypwoPpEf7zg=
+k8s.io/apimachinery v0.26.0/go.mod h1:tnPmbONNJ7ByJNz9+n9kMjNP8ON+1qoAIIC70lztu74=
 k8s.io/klog/v2 v2.80.1 h1:atnLQ121W371wYYFawwYx1aEY2eUfs4l3J72wtgAwV4=
 k8s.io/klog/v2 v2.80.1/go.mod h1:y1WjHnz7Dj687irZUWR/WLkLc5N1YHtjLdmgWjndZn0=
 k8s.io/utils v0.0.0-20230209194617-a36077c30491 h1:r0BAOLElQnnFhE/ApUsg3iHdVYYPBjNSSOMowRZxxsY=

pkg/nvmf/controllerserver.go

@@ -25,6 +25,10 @@ import (
 	"k8s.io/klog/v2"
 )
 
+const (
+	UseActualDeviceCapacity int64 = 0 // Use the actual device capacity
+)
+
 type ControllerServer struct {
 	Driver         *driver
 	deviceRegistry *DeviceRegistry
@@ -64,11 +68,27 @@ func (c *ControllerServer) CreateVolume(ctx context.Context, req *csi.CreateVolu
 		return nil, status.Errorf(codes.Internal, "device discovery failed: %v", err)
 	}
 
-	// TODO (cheolho.kang): In a future implementation, this method would:
+	// Acquire volume lock to prevent concurrent operations
-	// 1. Allocate a device for the volume
+	if acquired := c.Driver.volumeLocks.TryAcquire(volumeName); !acquired {
-	// 2. Store the allocation info in etcd
+		return nil, status.Errorf(codes.Aborted, "concurrent operation in progress for volume: %s", volumeName)
-	// 3. Return the allocated device information in the response
+	}
-	return nil, status.Errorf(codes.Unimplemented, "CreateVolume should implement by yourself. ")
+	defer c.Driver.volumeLocks.Release(volumeName)
+
+	// Allocate a device
+	allocatedDevice, err := c.deviceRegistry.AllocateDevice(volumeName)
+	if err != nil {
+		klog.Errorf("Failed to allocate device for volume %s: %v", volumeName, err)
+		return nil, status.Errorf(codes.ResourceExhausted, "no suitable device available: %v", err)
+	}
+
+	return &csi.CreateVolumeResponse{
+		Volume: &csi.Volume{
+			VolumeId:      allocatedDevice.Nqn,
+			CapacityBytes: UseActualDeviceCapacity, // PV will use the actual capacity
+			VolumeContext: parameters,
+			ContentSource: req.GetVolumeContentSource(),
+		},
+	}, nil
 }
 
 // DeleteVolume deletes a volume
@@ -80,7 +100,20 @@ func (c *ControllerServer) DeleteVolume(ctx context.Context, req *csi.DeleteVolu
 
 	klog.V(4).Infof("DeleteVolume called for volume ID %s", volumeID)
 
-	return nil, status.Errorf(codes.Unimplemented, "DeleteVolume should implement by yourself. ")
+	// Acquire lock to prevent concurrent operations on this volume
+	if acquired := c.Driver.volumeLocks.TryAcquire(volumeID); !acquired {
+		return nil, status.Errorf(codes.Aborted, "concurrent operation in progress for volume: %s", volumeID)
+	}
+	defer c.Driver.volumeLocks.Release(volumeID)
+
+	// Find the volume by NQN
+	// Note: volumeID is expected to be in NQN (NVMe Qualified Name) format.
+	// This assumption is valid because in CreateVolume, we assigned the device's NQN
+	// as the volumeID when returning the CreateVolumeResponse.
+	nqn := volumeID
+	c.deviceRegistry.ReleaseDevice(nqn)
+
+	return &csi.DeleteVolumeResponse{}, nil
 }
 
 func (c *ControllerServer) ControllerExpandVolume(ctx context.Context, req *csi.ControllerExpandVolumeRequest) (*csi.ControllerExpandVolumeResponse, error) {

pkg/nvmf/device_registry.go

@@ -92,6 +92,71 @@ func (r *DeviceRegistry) DiscoverDevices(params map[string]string) error {
 	return nil
 }
 
+// AllocateDevice selects and allocates a device for a volume
+func (r *DeviceRegistry) AllocateDevice(volumeName string) (*VolumeInfo, error) {
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+
+	// Check this volume is already allocated
+	if nqn, exists := r.volumeToNQN[volumeName]; exists {
+		return nil, fmt.Errorf("already allocated. PV: %s, device: %s", volumeName, nqn)
+	}
+
+	// Check if any devices are available
+	if len(r.availableNQNs) == 0 {
+		return nil, fmt.Errorf("no available devices found")
+	}
+
+	var nqn string
+	for n := range r.availableNQNs {
+		if r.devices[n].IsAllocated {
+			klog.Errorf("Device %s is marked as available but is already allocated. Device details: %+v", n, r.devices[n])
+			continue
+		}
+
+		nqn = n
+		break
+	}
+
+	if nqn == "" {
+		return nil, fmt.Errorf("no available devices found")
+	}
+
+	// Update tracking maps
+	delete(r.availableNQNs, nqn)
+	r.volumeToNQN[volumeName] = nqn
+	device := r.devices[nqn]
+	device.VolName = volumeName
+	device.IsAllocated = true
+
+	klog.V(4).Infof("[%d/%d] Allocated volume %s (NQN %s)", len(r.devices) - len(r.availableNQNs), len(r.devices), volumeName, nqn)
+
+	return device, nil
+}
+
+// ReleaseDevice releases a device allocation
+func (r *DeviceRegistry) ReleaseDevice(nqn string) {
+	r.mutex.Lock()
+	defer r.mutex.Unlock()
+
+
+	device, exists := r.devices[nqn]
+	if !exists {
+		// CSI spec requires idempotency: return success even if volume doesn't exist
+		// This allows safe retries and prevents errors when volume was already deleted
+		klog.Infof("Volume %s not found", nqn)
+		return
+	}
+
+	// Update tracking maps
+	device.IsAllocated = false
+	delete(r.volumeToNQN, device.VolName)
+	r.availableNQNs[nqn] = struct{}{}
+	device.VolName = ""
+
+	klog.V(4).Infof("[%d/%d] Released volume %s", len(r.devices) - len(r.availableNQNs), len(r.devices), nqn)
+}
+
 // discoverNVMeDevices runs NVMe discovery and returns available targets
 func discoverNVMeDevices(params map[string]string) (map[string]*nvmfDiskInfo, error) {
 	if params == nil {

pkg/nvmf/driver.go

@@ -21,6 +21,8 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 	"k8s.io/klog/v2"
+
+	"github.com/kubernetes-csi/csi-driver-nvmf/pkg/utils"
 )
 
 type driver struct {
@@ -30,6 +32,7 @@ type driver struct {
 
 	region       string
 	volumeMapDir string
+	volumeLocks  *utils.VolumeLocks
 
 	idServer         *IdentityServer
 	nodeServer       *NodeServer
@@ -53,6 +56,7 @@ func NewDriver(conf *GlobalConfig) *driver {
 		nodeId:       conf.NodeID,
 		region:       conf.Region,
 		volumeMapDir: conf.NVMfVolumeMapDir,
+		volumeLocks:  utils.NewVolumeLocks(),
 	}
 }
 

pkg/utils/utils.go

@@ -22,8 +22,22 @@ import (
 	"io"
 	"os"
 	"strings"
+	"sync"
+
+	"k8s.io/apimachinery/pkg/util/sets"
 )
 
+type VolumeLocks struct {
+	locks sets.String //nolint:staticcheck
+	mux   sync.Mutex
+}
+
+func NewVolumeLocks() *VolumeLocks {
+	return &VolumeLocks{
+		locks: sets.NewString(),
+	}
+}
+
 // IsFileExisting check file exist in volume driver
 func IsFileExisting(filename string) bool {
 	_, err := os.Stat(filename)
@@ -37,6 +51,22 @@ func IsFileExisting(filename string) bool {
 	return true
 }
 
+func (vl *VolumeLocks) TryAcquire(volumeID string) bool {
+	vl.mux.Lock()
+	defer vl.mux.Unlock()
+	if vl.locks.Has(volumeID) {
+		return false
+	}
+	vl.locks.Insert(volumeID)
+	return true
+}
+
+func (vl *VolumeLocks) Release(volumeID string) {
+	vl.mux.Lock()
+	defer vl.mux.Unlock()
+	vl.locks.Delete(volumeID)
+}
+
 func ParseEndpoint(ep string) (string, string, error) {
 	if strings.HasPrefix(strings.ToLower(ep), "unix://") || strings.HasPrefix(strings.ToLower(ep), "tcp://") {
 		s := strings.SplitN(ep, "://", 2)

vendor/k8s.io/apimachinery/LICENSE

@@ -0,0 +1,202 @@
+
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+      the terms of any separate license agreement you may have executed
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vendor/k8s.io/apimachinery/pkg/util/sets/byte.go

@@ -0,0 +1,137 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+// Byte is a set of bytes, implemented via map[byte]struct{} for minimal memory consumption.
+//
+// Deprecated: use generic Set instead.
+// new ways:
+// s1 := Set[byte]{}
+// s2 := New[byte]()
+type Byte map[byte]Empty
+
+// NewByte creates a Byte from a list of values.
+func NewByte(items ...byte) Byte {
+	return Byte(New[byte](items...))
+}
+
+// ByteKeySet creates a Byte from a keys of a map[byte](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func ByteKeySet[T any](theMap map[byte]T) Byte {
+	return Byte(KeySet(theMap))
+}
+
+// Insert adds items to the set.
+func (s Byte) Insert(items ...byte) Byte {
+	return Byte(cast(s).Insert(items...))
+}
+
+// Delete removes all items from the set.
+func (s Byte) Delete(items ...byte) Byte {
+	return Byte(cast(s).Delete(items...))
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Byte) Has(item byte) bool {
+	return cast(s).Has(item)
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Byte) HasAll(items ...byte) bool {
+	return cast(s).HasAll(items...)
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Byte) HasAny(items ...byte) bool {
+	return cast(s).HasAny(items...)
+}
+
+// Clone returns a new set which is a copy of the current set.
+func (s Byte) Clone() Byte {
+	return Byte(cast(s).Clone())
+}
+
+// Difference returns a set of objects that are not in s2.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s1 Byte) Difference(s2 Byte) Byte {
+	return Byte(cast(s1).Difference(cast(s2)))
+}
+
+// SymmetricDifference returns a set of elements which are in either of the sets, but not in their intersection.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.SymmetricDifference(s2) = {a3, a4, a5}
+// s2.SymmetricDifference(s1) = {a3, a4, a5}
+func (s1 Byte) SymmetricDifference(s2 Byte) Byte {
+	return Byte(cast(s1).SymmetricDifference(cast(s2)))
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Byte) Union(s2 Byte) Byte {
+	return Byte(cast(s1).Union(cast(s2)))
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Byte) Intersection(s2 Byte) Byte {
+	return Byte(cast(s1).Intersection(cast(s2)))
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Byte) IsSuperset(s2 Byte) bool {
+	return cast(s1).IsSuperset(cast(s2))
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Byte) Equal(s2 Byte) bool {
+	return cast(s1).Equal(cast(s2))
+}
+
+// List returns the contents as a sorted byte slice.
+func (s Byte) List() []byte {
+	return List(cast(s))
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Byte) UnsortedList() []byte {
+	return cast(s).UnsortedList()
+}
+
+// PopAny returns a single element from the set.
+func (s Byte) PopAny() (byte, bool) {
+	return cast(s).PopAny()
+}
+
+// Len returns the size of the set.
+func (s Byte) Len() int {
+	return len(s)
+}

vendor/k8s.io/apimachinery/pkg/util/sets/doc.go

@@ -0,0 +1,19 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package sets has generic set and specified sets. Generic set will
+// replace specified ones over time. And specific ones are deprecated.
+package sets

vendor/k8s.io/apimachinery/pkg/util/sets/empty.go

@@ -0,0 +1,21 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+// Empty is public since it is used by some internal API objects for conversions between external
+// string arrays and internal sets, and conversion logic requires public types today.
+type Empty struct{}

vendor/k8s.io/apimachinery/pkg/util/sets/int.go

@@ -0,0 +1,137 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+// Int is a set of ints, implemented via map[int]struct{} for minimal memory consumption.
+//
+// Deprecated: use generic Set instead.
+// new ways:
+// s1 := Set[int]{}
+// s2 := New[int]()
+type Int map[int]Empty
+
+// NewInt creates a Int from a list of values.
+func NewInt(items ...int) Int {
+	return Int(New[int](items...))
+}
+
+// IntKeySet creates a Int from a keys of a map[int](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func IntKeySet[T any](theMap map[int]T) Int {
+	return Int(KeySet(theMap))
+}
+
+// Insert adds items to the set.
+func (s Int) Insert(items ...int) Int {
+	return Int(cast(s).Insert(items...))
+}
+
+// Delete removes all items from the set.
+func (s Int) Delete(items ...int) Int {
+	return Int(cast(s).Delete(items...))
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Int) Has(item int) bool {
+	return cast(s).Has(item)
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Int) HasAll(items ...int) bool {
+	return cast(s).HasAll(items...)
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Int) HasAny(items ...int) bool {
+	return cast(s).HasAny(items...)
+}
+
+// Clone returns a new set which is a copy of the current set.
+func (s Int) Clone() Int {
+	return Int(cast(s).Clone())
+}
+
+// Difference returns a set of objects that are not in s2.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s1 Int) Difference(s2 Int) Int {
+	return Int(cast(s1).Difference(cast(s2)))
+}
+
+// SymmetricDifference returns a set of elements which are in either of the sets, but not in their intersection.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.SymmetricDifference(s2) = {a3, a4, a5}
+// s2.SymmetricDifference(s1) = {a3, a4, a5}
+func (s1 Int) SymmetricDifference(s2 Int) Int {
+	return Int(cast(s1).SymmetricDifference(cast(s2)))
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Int) Union(s2 Int) Int {
+	return Int(cast(s1).Union(cast(s2)))
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Int) Intersection(s2 Int) Int {
+	return Int(cast(s1).Intersection(cast(s2)))
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Int) IsSuperset(s2 Int) bool {
+	return cast(s1).IsSuperset(cast(s2))
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Int) Equal(s2 Int) bool {
+	return cast(s1).Equal(cast(s2))
+}
+
+// List returns the contents as a sorted int slice.
+func (s Int) List() []int {
+	return List(cast(s))
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Int) UnsortedList() []int {
+	return cast(s).UnsortedList()
+}
+
+// PopAny returns a single element from the set.
+func (s Int) PopAny() (int, bool) {
+	return cast(s).PopAny()
+}
+
+// Len returns the size of the set.
+func (s Int) Len() int {
+	return len(s)
+}

vendor/k8s.io/apimachinery/pkg/util/sets/int32.go

@@ -0,0 +1,137 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+// Int32 is a set of int32s, implemented via map[int32]struct{} for minimal memory consumption.
+//
+// Deprecated: use generic Set instead.
+// new ways:
+// s1 := Set[int32]{}
+// s2 := New[int32]()
+type Int32 map[int32]Empty
+
+// NewInt32 creates a Int32 from a list of values.
+func NewInt32(items ...int32) Int32 {
+	return Int32(New[int32](items...))
+}
+
+// Int32KeySet creates a Int32 from a keys of a map[int32](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func Int32KeySet[T any](theMap map[int32]T) Int32 {
+	return Int32(KeySet(theMap))
+}
+
+// Insert adds items to the set.
+func (s Int32) Insert(items ...int32) Int32 {
+	return Int32(cast(s).Insert(items...))
+}
+
+// Delete removes all items from the set.
+func (s Int32) Delete(items ...int32) Int32 {
+	return Int32(cast(s).Delete(items...))
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Int32) Has(item int32) bool {
+	return cast(s).Has(item)
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Int32) HasAll(items ...int32) bool {
+	return cast(s).HasAll(items...)
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Int32) HasAny(items ...int32) bool {
+	return cast(s).HasAny(items...)
+}
+
+// Clone returns a new set which is a copy of the current set.
+func (s Int32) Clone() Int32 {
+	return Int32(cast(s).Clone())
+}
+
+// Difference returns a set of objects that are not in s2.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s1 Int32) Difference(s2 Int32) Int32 {
+	return Int32(cast(s1).Difference(cast(s2)))
+}
+
+// SymmetricDifference returns a set of elements which are in either of the sets, but not in their intersection.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.SymmetricDifference(s2) = {a3, a4, a5}
+// s2.SymmetricDifference(s1) = {a3, a4, a5}
+func (s1 Int32) SymmetricDifference(s2 Int32) Int32 {
+	return Int32(cast(s1).SymmetricDifference(cast(s2)))
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Int32) Union(s2 Int32) Int32 {
+	return Int32(cast(s1).Union(cast(s2)))
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Int32) Intersection(s2 Int32) Int32 {
+	return Int32(cast(s1).Intersection(cast(s2)))
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Int32) IsSuperset(s2 Int32) bool {
+	return cast(s1).IsSuperset(cast(s2))
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Int32) Equal(s2 Int32) bool {
+	return cast(s1).Equal(cast(s2))
+}
+
+// List returns the contents as a sorted int32 slice.
+func (s Int32) List() []int32 {
+	return List(cast(s))
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Int32) UnsortedList() []int32 {
+	return cast(s).UnsortedList()
+}
+
+// PopAny returns a single element from the set.
+func (s Int32) PopAny() (int32, bool) {
+	return cast(s).PopAny()
+}
+
+// Len returns the size of the set.
+func (s Int32) Len() int {
+	return len(s)
+}

vendor/k8s.io/apimachinery/pkg/util/sets/int64.go

@@ -0,0 +1,137 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+// Int64 is a set of int64s, implemented via map[int64]struct{} for minimal memory consumption.
+//
+// Deprecated: use generic Set instead.
+// new ways:
+// s1 := Set[int64]{}
+// s2 := New[int64]()
+type Int64 map[int64]Empty
+
+// NewInt64 creates a Int64 from a list of values.
+func NewInt64(items ...int64) Int64 {
+	return Int64(New[int64](items...))
+}
+
+// Int64KeySet creates a Int64 from a keys of a map[int64](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func Int64KeySet[T any](theMap map[int64]T) Int64 {
+	return Int64(KeySet(theMap))
+}
+
+// Insert adds items to the set.
+func (s Int64) Insert(items ...int64) Int64 {
+	return Int64(cast(s).Insert(items...))
+}
+
+// Delete removes all items from the set.
+func (s Int64) Delete(items ...int64) Int64 {
+	return Int64(cast(s).Delete(items...))
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Int64) Has(item int64) bool {
+	return cast(s).Has(item)
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Int64) HasAll(items ...int64) bool {
+	return cast(s).HasAll(items...)
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Int64) HasAny(items ...int64) bool {
+	return cast(s).HasAny(items...)
+}
+
+// Clone returns a new set which is a copy of the current set.
+func (s Int64) Clone() Int64 {
+	return Int64(cast(s).Clone())
+}
+
+// Difference returns a set of objects that are not in s2.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s1 Int64) Difference(s2 Int64) Int64 {
+	return Int64(cast(s1).Difference(cast(s2)))
+}
+
+// SymmetricDifference returns a set of elements which are in either of the sets, but not in their intersection.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.SymmetricDifference(s2) = {a3, a4, a5}
+// s2.SymmetricDifference(s1) = {a3, a4, a5}
+func (s1 Int64) SymmetricDifference(s2 Int64) Int64 {
+	return Int64(cast(s1).SymmetricDifference(cast(s2)))
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Int64) Union(s2 Int64) Int64 {
+	return Int64(cast(s1).Union(cast(s2)))
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Int64) Intersection(s2 Int64) Int64 {
+	return Int64(cast(s1).Intersection(cast(s2)))
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Int64) IsSuperset(s2 Int64) bool {
+	return cast(s1).IsSuperset(cast(s2))
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Int64) Equal(s2 Int64) bool {
+	return cast(s1).Equal(cast(s2))
+}
+
+// List returns the contents as a sorted int64 slice.
+func (s Int64) List() []int64 {
+	return List(cast(s))
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Int64) UnsortedList() []int64 {
+	return cast(s).UnsortedList()
+}
+
+// PopAny returns a single element from the set.
+func (s Int64) PopAny() (int64, bool) {
+	return cast(s).PopAny()
+}
+
+// Len returns the size of the set.
+func (s Int64) Len() int {
+	return len(s)
+}

vendor/k8s.io/apimachinery/pkg/util/sets/ordered.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+// ordered is a constraint that permits any ordered type: any type
+// that supports the operators < <= >= >.
+// If future releases of Go add new ordered types,
+// this constraint will be modified to include them.
+type ordered interface {
+	integer | float | ~string
+}
+
+// integer is a constraint that permits any integer type.
+// If future releases of Go add new predeclared integer types,
+// this constraint will be modified to include them.
+type integer interface {
+	signed | unsigned
+}
+
+// float is a constraint that permits any floating-point type.
+// If future releases of Go add new predeclared floating-point types,
+// this constraint will be modified to include them.
+type float interface {
+	~float32 | ~float64
+}
+
+// signed is a constraint that permits any signed integer type.
+// If future releases of Go add new predeclared signed integer types,
+// this constraint will be modified to include them.
+type signed interface {
+	~int | ~int8 | ~int16 | ~int32 | ~int64
+}
+
+// unsigned is a constraint that permits any unsigned integer type.
+// If future releases of Go add new predeclared unsigned integer types,
+// this constraint will be modified to include them.
+type unsigned interface {
+	~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr
+}

vendor/k8s.io/apimachinery/pkg/util/sets/set.go

@@ -0,0 +1,227 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+import (
+	"sort"
+)
+
+// Set is a set of the same type elements, implemented via map[comparable]struct{} for minimal memory consumption.
+type Set[T comparable] map[T]Empty
+
+// cast transforms specified set to generic Set[T].
+func cast[T comparable](s map[T]Empty) Set[T] { return s }
+
+// New creates a Set from a list of values.
+// NOTE: type param must be explicitly instantiated if given items are empty.
+func New[T comparable](items ...T) Set[T] {
+	ss := make(Set[T], len(items))
+	ss.Insert(items...)
+	return ss
+}
+
+// KeySet creates a Set from a keys of a map[comparable](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func KeySet[T comparable, V any](theMap map[T]V) Set[T] {
+	ret := Set[T]{}
+	for keyValue := range theMap {
+		ret.Insert(keyValue)
+	}
+	return ret
+}
+
+// Insert adds items to the set.
+func (s Set[T]) Insert(items ...T) Set[T] {
+	for _, item := range items {
+		s[item] = Empty{}
+	}
+	return s
+}
+
+func Insert[T comparable](set Set[T], items ...T) Set[T] {
+	return set.Insert(items...)
+}
+
+// Delete removes all items from the set.
+func (s Set[T]) Delete(items ...T) Set[T] {
+	for _, item := range items {
+		delete(s, item)
+	}
+	return s
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s Set[T]) Has(item T) bool {
+	_, contained := s[item]
+	return contained
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s Set[T]) HasAll(items ...T) bool {
+	for _, item := range items {
+		if !s.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s Set[T]) HasAny(items ...T) bool {
+	for _, item := range items {
+		if s.Has(item) {
+			return true
+		}
+	}
+	return false
+}
+
+// Clone returns a new set which is a copy of the current set.
+func (s Set[T]) Clone() Set[T] {
+	result := make(Set[T], len(s))
+	for key := range s {
+		result.Insert(key)
+	}
+	return result
+}
+
+// Difference returns a set of objects that are not in s2.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s1 Set[T]) Difference(s2 Set[T]) Set[T] {
+	result := New[T]()
+	for key := range s1 {
+		if !s2.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// SymmetricDifference returns a set of elements which are in either of the sets, but not in their intersection.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.SymmetricDifference(s2) = {a3, a4, a5}
+// s2.SymmetricDifference(s1) = {a3, a4, a5}
+func (s1 Set[T]) SymmetricDifference(s2 Set[T]) Set[T] {
+	return s1.Difference(s2).Union(s2.Difference(s1))
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 Set[T]) Union(s2 Set[T]) Set[T] {
+	result := s1.Clone()
+	for key := range s2 {
+		result.Insert(key)
+	}
+	return result
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 Set[T]) Intersection(s2 Set[T]) Set[T] {
+	var walk, other Set[T]
+	result := New[T]()
+	if s1.Len() < s2.Len() {
+		walk = s1
+		other = s2
+	} else {
+		walk = s2
+		other = s1
+	}
+	for key := range walk {
+		if other.Has(key) {
+			result.Insert(key)
+		}
+	}
+	return result
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 Set[T]) IsSuperset(s2 Set[T]) bool {
+	for item := range s2 {
+		if !s1.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 Set[T]) Equal(s2 Set[T]) bool {
+	return len(s1) == len(s2) && s1.IsSuperset(s2)
+}
+
+type sortableSliceOfGeneric[T ordered] []T
+
+func (g sortableSliceOfGeneric[T]) Len() int           { return len(g) }
+func (g sortableSliceOfGeneric[T]) Less(i, j int) bool { return less[T](g[i], g[j]) }
+func (g sortableSliceOfGeneric[T]) Swap(i, j int)      { g[i], g[j] = g[j], g[i] }
+
+// List returns the contents as a sorted T slice.
+//
+// This is a separate function and not a method because not all types supported
+// by Generic are ordered and only those can be sorted.
+func List[T ordered](s Set[T]) []T {
+	res := make(sortableSliceOfGeneric[T], 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	sort.Sort(res)
+	return res
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s Set[T]) UnsortedList() []T {
+	res := make([]T, 0, len(s))
+	for key := range s {
+		res = append(res, key)
+	}
+	return res
+}
+
+// PopAny returns a single element from the set.
+func (s Set[T]) PopAny() (T, bool) {
+	for key := range s {
+		s.Delete(key)
+		return key, true
+	}
+	var zeroValue T
+	return zeroValue, false
+}
+
+// Len returns the size of the set.
+func (s Set[T]) Len() int {
+	return len(s)
+}
+
+func less[T ordered](lhs, rhs T) bool {
+	return lhs < rhs
+}

vendor/k8s.io/apimachinery/pkg/util/sets/string.go

@@ -0,0 +1,137 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sets
+
+// String is a set of strings, implemented via map[string]struct{} for minimal memory consumption.
+//
+// Deprecated: use generic Set instead.
+// new ways:
+// s1 := Set[string]{}
+// s2 := New[string]()
+type String map[string]Empty
+
+// NewString creates a String from a list of values.
+func NewString(items ...string) String {
+	return String(New[string](items...))
+}
+
+// StringKeySet creates a String from a keys of a map[string](? extends interface{}).
+// If the value passed in is not actually a map, this will panic.
+func StringKeySet[T any](theMap map[string]T) String {
+	return String(KeySet(theMap))
+}
+
+// Insert adds items to the set.
+func (s String) Insert(items ...string) String {
+	return String(cast(s).Insert(items...))
+}
+
+// Delete removes all items from the set.
+func (s String) Delete(items ...string) String {
+	return String(cast(s).Delete(items...))
+}
+
+// Has returns true if and only if item is contained in the set.
+func (s String) Has(item string) bool {
+	return cast(s).Has(item)
+}
+
+// HasAll returns true if and only if all items are contained in the set.
+func (s String) HasAll(items ...string) bool {
+	return cast(s).HasAll(items...)
+}
+
+// HasAny returns true if any items are contained in the set.
+func (s String) HasAny(items ...string) bool {
+	return cast(s).HasAny(items...)
+}
+
+// Clone returns a new set which is a copy of the current set.
+func (s String) Clone() String {
+	return String(cast(s).Clone())
+}
+
+// Difference returns a set of objects that are not in s2.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.Difference(s2) = {a3}
+// s2.Difference(s1) = {a4, a5}
+func (s1 String) Difference(s2 String) String {
+	return String(cast(s1).Difference(cast(s2)))
+}
+
+// SymmetricDifference returns a set of elements which are in either of the sets, but not in their intersection.
+// For example:
+// s1 = {a1, a2, a3}
+// s2 = {a1, a2, a4, a5}
+// s1.SymmetricDifference(s2) = {a3, a4, a5}
+// s2.SymmetricDifference(s1) = {a3, a4, a5}
+func (s1 String) SymmetricDifference(s2 String) String {
+	return String(cast(s1).SymmetricDifference(cast(s2)))
+}
+
+// Union returns a new set which includes items in either s1 or s2.
+// For example:
+// s1 = {a1, a2}
+// s2 = {a3, a4}
+// s1.Union(s2) = {a1, a2, a3, a4}
+// s2.Union(s1) = {a1, a2, a3, a4}
+func (s1 String) Union(s2 String) String {
+	return String(cast(s1).Union(cast(s2)))
+}
+
+// Intersection returns a new set which includes the item in BOTH s1 and s2
+// For example:
+// s1 = {a1, a2}
+// s2 = {a2, a3}
+// s1.Intersection(s2) = {a2}
+func (s1 String) Intersection(s2 String) String {
+	return String(cast(s1).Intersection(cast(s2)))
+}
+
+// IsSuperset returns true if and only if s1 is a superset of s2.
+func (s1 String) IsSuperset(s2 String) bool {
+	return cast(s1).IsSuperset(cast(s2))
+}
+
+// Equal returns true if and only if s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 String) Equal(s2 String) bool {
+	return cast(s1).Equal(cast(s2))
+}
+
+// List returns the contents as a sorted string slice.
+func (s String) List() []string {
+	return List(cast(s))
+}
+
+// UnsortedList returns the slice with contents in random order.
+func (s String) UnsortedList() []string {
+	return cast(s).UnsortedList()
+}
+
+// PopAny returns a single element from the set.
+func (s String) PopAny() (string, bool) {
+	return cast(s).PopAny()
+}
+
+// Len returns the size of the set.
+func (s String) Len() int {
+	return len(s)
+}