scsi: device_handler: alua: Revert "Move a scsi_device_put() call out of alua_check_v...

There is a bug in commit 0b25e17e9018 ("scsi: alua: Move a
scsi_device_put() call out of alua_check_vpd()"): that patch may cause
alua_rtpg_queue() callers to call scsi_device_put() even if that function
should not be called. Revert that commit to prepare for a different
solution.

Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Wilck <mwilck@suse.com>
Cc: Sachin Sant <sachinp@linux.ibm.com>
Cc: Benjamin Block <bblock@linux.ibm.com>
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Reported-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221117183626.2656196-2-bvanassche@acm.org
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 693cd827e138416dc59a58d2e7fc7256bc6926b6..bd4ee294f5c78776b22f302b99f64c846ee10415 100644 (file)
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -324,7 +324,6 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
        struct alua_port_group *pg, *old_pg = NULL;
        bool pg_updated = false;
        unsigned long flags;
-       bool put_sdev;
 
        group_id = scsi_vpd_tpg_id(sdev, &rel_port);
        if (group_id < 0) {
@@ -374,14 +373,11 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
                list_add_rcu(&h->node, &pg->dh_list);
        spin_unlock_irqrestore(&pg->lock, flags);
 
-       put_sdev = alua_rtpg_queue(rcu_dereference_protected(h->pg,
+       alua_rtpg_queue(rcu_dereference_protected(h->pg,
                                                  lockdep_is_held(&h->pg_lock)),
                        sdev, NULL, true);
        spin_unlock(&h->pg_lock);
 
-       if (put_sdev)
-               scsi_device_put(sdev);
-
        if (old_pg)
                kref_put(&old_pg->kref, release_port_group);
 
@@ -982,10 +978,9 @@ queue_rtpg:
  *         RTPG already has been scheduled.
  *
  * Returns true if and only if alua_rtpg_work() will be called asynchronously.
- * That function is responsible for calling @qdata->fn(). If this function
- * returns true, the caller is responsible for invoking scsi_device_put(@sdev).
+ * That function is responsible for calling @qdata->fn().
  */
-static bool __must_check alua_rtpg_queue(struct alua_port_group *pg,
+static bool alua_rtpg_queue(struct alua_port_group *pg,
                            struct scsi_device *sdev,
                            struct alua_queue_data *qdata, bool force)
 {
@@ -1024,6 +1019,8 @@ static bool __must_check alua_rtpg_queue(struct alua_port_group *pg,
                else
                        kref_put(&pg->kref, release_port_group);
        }
+       if (sdev)
+               scsi_device_put(sdev);
 
        return true;
 }
@@ -1130,12 +1127,10 @@ static int alua_activate(struct scsi_device *sdev,
        rcu_read_unlock();
        mutex_unlock(&h->init_mutex);
 
-       if (alua_rtpg_queue(pg, sdev, qdata, true)) {
-               scsi_device_put(sdev);
+       if (alua_rtpg_queue(pg, sdev, qdata, true))
                fn = NULL;
-       } else {
+       else
                err = SCSI_DH_DEV_OFFLINED;
-       }
        kref_put(&pg->kref, release_port_group);
 out:
        if (fn)
@@ -1161,9 +1156,7 @@ static void alua_check(struct scsi_device *sdev, bool force)
                return;
        }
        rcu_read_unlock();
-
-       if (alua_rtpg_queue(pg, sdev, NULL, force))
-               scsi_device_put(sdev);
+       alua_rtpg_queue(pg, sdev, NULL, force);
        kref_put(&pg->kref, release_port_group);
 }