[PATCH] scsi: mpi3mr: use ida to manage mrioc's id

[Guixin Liu <kanie@xxxxxxxxxxxxxxxxx>]

To ensure that the same id is not obtained during concurrent
execution of the probe, an ida is used to manage the mrioc's
id.

Signed-off-by: Guixin Liu <kanie@xxxxxxxxxxxxxxxxx>
---
 drivers/scsi/mpi3mr/mpi3mr.h    |  2 +-
 drivers/scsi/mpi3mr/mpi3mr_os.c | 12 ++++++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/mpi3mr/mpi3mr.h b/drivers/scsi/mpi3mr/mpi3mr.h
index ae98d15c30b1..ec5b92c9f9e5 100644
--- a/drivers/scsi/mpi3mr/mpi3mr.h
+++ b/drivers/scsi/mpi3mr/mpi3mr.h
@@ -1047,7 +1047,7 @@ struct mpi3mr_ioc {
 	struct list_head list;
 	struct pci_dev *pdev;
 	struct Scsi_Host *shost;
-	u8 id;
+	int id;
 	int cpu_count;
 	bool enable_segqueue;
 	u32 irqpoll_sleep;
diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
index 040031eb0c12..8d05cb3e0c90 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_os.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
@@ -8,11 +8,12 @@
  */
 
 #include "mpi3mr.h"
+#include <linux/idr.h>
 
 /* global driver scop variables */
 LIST_HEAD(mrioc_list);
 DEFINE_SPINLOCK(mrioc_list_lock);
-static int mrioc_ids;
+static DEFINE_IDA(mrioc_ida);
 static int warn_non_secure_ctlr;
 atomic64_t event_counter;
 
@@ -5060,7 +5061,10 @@ mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	}
 
 	mrioc = shost_priv(shost);
-	mrioc->id = mrioc_ids++;
+	retval = ida_alloc(&mrioc_ida, GFP_KERNEL);
+	if (retval < 0)
+		goto id_alloc_failed;
+	mrioc->id = retval;
 	sprintf(mrioc->driver_name, "%s", MPI3MR_DRIVER_NAME);
 	sprintf(mrioc->name, "%s%d", mrioc->driver_name, mrioc->id);
 	INIT_LIST_HEAD(&mrioc->list);
@@ -5207,9 +5211,11 @@ mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 resource_alloc_failed:
 	destroy_workqueue(mrioc->fwevt_worker_thread);
 fwevtthread_failed:
+	ida_free(&mrioc_ida, mrioc->id);
 	spin_lock(&mrioc_list_lock);
 	list_del(&mrioc->list);
 	spin_unlock(&mrioc_list_lock);
+id_alloc_failed:
 	scsi_host_put(shost);
 shost_failed:
 	return retval;
@@ -5295,6 +5301,7 @@ static void mpi3mr_remove(struct pci_dev *pdev)
 		mrioc->sas_hba.num_phys = 0;
 	}
 
+	ida_free(&mrioc_ida, mrioc->id);
 	spin_lock(&mrioc_list_lock);
 	list_del(&mrioc->list);
 	spin_unlock(&mrioc_list_lock);
@@ -5502,6 +5509,7 @@ static void __exit mpi3mr_exit(void)
 			   &driver_attr_event_counter);
 	pci_unregister_driver(&mpi3mr_pci_driver);
 	sas_release_transport(mpi3mr_transport_template);
+	ida_destroy(&mrioc_ida);
 }
 
 module_init(mpi3mr_init);
-- 
2.43.0