Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull more SCSI updates from James Bottomley:
 "Mostly small bug fixes and trivial updates.

  The major new core update is a change to the way device, target and
  host reference counting is done to try to make it more robust (this
  change has soaked for a while to try to winkle out any bugs)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: pm8001: Fix typo 'the the' in comment
  scsi: megaraid_sas: Remove redundant variable cmd_type
  scsi: FlashPoint: Remove redundant variable bm_int_st
  scsi: zfcp: Fix missing auto port scan and thus missing target ports
  scsi: core: Call blk_mq_free_tag_set() earlier
  scsi: core: Simplify LLD module reference counting
  scsi: core: Make sure that hosts outlive targets
  scsi: core: Make sure that targets outlive devices
  scsi: ufs: ufs-pci: Correct check for RESET DSM
  scsi: target: core: De-RCU of se_lun and se_lun acl
  scsi: target: core: Fix race during ACL removal
  scsi: ufs: core: Correct ufshcd_shutdown() flow
  scsi: ufs: core: Increase the maximum data buffer size
  scsi: lpfc: Check the return value of alloc_workqueue()

1 files changed, 13 insertions, 5 deletions

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 26bf3b153595..0738238ed6cc 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -190,6 +190,15 @@ void scsi_remove_host(struct Scsi_Host *shost)
 	transport_unregister_device(&shost->shost_gendev);
 	device_unregister(&shost->shost_dev);
 	device_del(&shost->shost_gendev);
+
+	/*
+	 * After scsi_remove_host() has returned the scsi LLD module can be
+	 * unloaded and/or the host resources can be released. Hence wait until
+	 * the dependent SCSI targets and devices are gone before returning.
+	 */
+	wait_event(shost->targets_wq, atomic_read(&shost->target_count) == 0);
+
+	scsi_mq_destroy_tags(shost);
 }
 EXPORT_SYMBOL(scsi_remove_host);
 
@@ -300,8 +309,8 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
 	return error;
 
 	/*
-	 * Any host allocation in this function will be freed in
-	 * scsi_host_dev_release().
+	 * Any resources associated with the SCSI host in this function except
+	 * the tag set will be freed by scsi_host_dev_release().
 	 */
  out_del_dev:
 	device_del(&shost->shost_dev);
@@ -317,6 +326,7 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
 	pm_runtime_disable(&shost->shost_gendev);
 	pm_runtime_set_suspended(&shost->shost_gendev);
 	pm_runtime_put_noidle(&shost->shost_gendev);
+	scsi_mq_destroy_tags(shost);
  fail:
 	return error;
 }
@@ -350,9 +360,6 @@ static void scsi_host_dev_release(struct device *dev)
 		kfree(dev_name(&shost->shost_dev));
 	}
 
-	if (shost->tag_set.tags)
-		scsi_mq_destroy_tags(shost);
-
 	kfree(shost->shost_data);
 
 	ida_free(&host_index_ida, shost->host_no);
@@ -399,6 +406,7 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
 	INIT_LIST_HEAD(&shost->starved_list);
 	init_waitqueue_head(&shost->host_wait);
 	mutex_init(&shost->scan_mutex);
+	init_waitqueue_head(&shost->targets_wq);
 
 	index = ida_alloc(&host_index_ida, GFP_KERNEL);
 	if (index < 0) {