[5.15,068/124] scsi: iscsi: Release endpoint ID when its freed

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index c7b1b2e8bb02..bcdfcb25349a 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -86,6 +86,9 @@  struct iscsi_internal {
 	struct transport_container session_cont;
 };
 
+static DEFINE_IDR(iscsi_ep_idr);
+static DEFINE_MUTEX(iscsi_ep_idr_mutex);
+
 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
 static struct workqueue_struct *iscsi_eh_timer_workq;
 
@@ -169,6 +172,11 @@  struct device_attribute dev_attr_##_prefix##_##_name =	\
 static void iscsi_endpoint_release(struct device *dev)
 {
 	struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
+
+	mutex_lock(&iscsi_ep_idr_mutex);
+	idr_remove(&iscsi_ep_idr, ep->id);
+	mutex_unlock(&iscsi_ep_idr_mutex);
+
 	kfree(ep);
 }
 
@@ -181,7 +189,7 @@  static ssize_t
 show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
-	return sysfs_emit(buf, "%llu\n", (unsigned long long) ep->id);
+	return sysfs_emit(buf, "%d\n", ep->id);
 }
 static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 
@@ -194,48 +202,32 @@  static struct attribute_group iscsi_endpoint_group = {
 	.attrs = iscsi_endpoint_attrs,
 };
 
-#define ISCSI_MAX_EPID -1
-
-static int iscsi_match_epid(struct device *dev, const void *data)
-{
-	struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
-	const uint64_t *epid = data;
-
-	return *epid == ep->id;
-}
-
 struct iscsi_endpoint *
 iscsi_create_endpoint(int dd_size)
 {
-	struct device *dev;
 	struct iscsi_endpoint *ep;
-	uint64_t id;
-	int err;
-
-	for (id = 1; id < ISCSI_MAX_EPID; id++) {
-		dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
-					iscsi_match_epid);
-		if (!dev)
-			break;
-		else
-			put_device(dev);
-	}
-	if (id == ISCSI_MAX_EPID) {
-		printk(KERN_ERR "Too many connections. Max supported %u\n",
-		       ISCSI_MAX_EPID - 1);
-		return NULL;
-	}
+	int err, id;
 
 	ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
 	if (!ep)
 		return NULL;
 
+	mutex_lock(&iscsi_ep_idr_mutex);
+	id = idr_alloc(&iscsi_ep_idr, ep, 0, -1, GFP_NOIO);
+	if (id < 0) {
+		mutex_unlock(&iscsi_ep_idr_mutex);
+		printk(KERN_ERR "Could not allocate endpoint ID. Error %d.\n",
+		       id);
+		goto free_ep;
+	}
+	mutex_unlock(&iscsi_ep_idr_mutex);
+
 	ep->id = id;
 	ep->dev.class = &iscsi_endpoint_class;
-	dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
+	dev_set_name(&ep->dev, "ep-%d", id);
 	err = device_register(&ep->dev);
         if (err)
-                goto free_ep;
+		goto free_id;
 
 	err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
 	if (err)
@@ -249,6 +241,10 @@  iscsi_create_endpoint(int dd_size)
 	device_unregister(&ep->dev);
 	return NULL;
 
+free_id:
+	mutex_lock(&iscsi_ep_idr_mutex);
+	idr_remove(&iscsi_ep_idr, id);
+	mutex_unlock(&iscsi_ep_idr_mutex);
 free_ep:
 	kfree(ep);
 	return NULL;
@@ -276,14 +272,17 @@  EXPORT_SYMBOL_GPL(iscsi_put_endpoint);
  */
 struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
 {
-	struct device *dev;
+	struct iscsi_endpoint *ep;
 
-	dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
-				iscsi_match_epid);
-	if (!dev)
-		return NULL;
+	mutex_lock(&iscsi_ep_idr_mutex);
+	ep = idr_find(&iscsi_ep_idr, handle);
+	if (!ep)
+		goto unlock;
 
-	return iscsi_dev_to_endpoint(dev);
+	get_device(&ep->dev);
+unlock:
+	mutex_unlock(&iscsi_ep_idr_mutex);
+	return ep;
 }
 EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 037c77fb5dc5..3ecf9702287b 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -296,7 +296,7 @@  extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
 struct iscsi_endpoint {
 	void *dd_data;			/* LLD private data */
 	struct device dev;
-	uint64_t id;
+	int id;
 	struct iscsi_cls_conn *conn;
 };