1 files changed, 68 insertions, 46 deletions

diff --git a/drivers/staging/unisys/visorhba/visorhba_main.c b/drivers/staging/unisys/visorhba/visorhba_main.c
index e93bb1dbfd97..6a4570d10642 100644
--- a/drivers/staging/unisys/visorhba/visorhba_main.c
+++ b/drivers/staging/unisys/visorhba/visorhba_main.c
@@ -52,6 +52,8 @@ static int visorhba_resume(struct visor_device *dev,
 
 static ssize_t info_debugfs_read(struct file *file, char __user *buf,
 				 size_t len, loff_t *offset);
+static int set_no_disk_inquiry_result(unsigned char *buf,
+				      size_t len, bool is_lun0);
 static struct dentry *visorhba_debugfs_dir;
 static const struct file_operations debugfs_info_fops = {
 	.read = info_debugfs_read,
@@ -83,12 +85,6 @@ static struct visor_driver visorhba_driver = {
 MODULE_DEVICE_TABLE(visorbus, visorhba_channel_types);
 MODULE_ALIAS("visorbus:" SPAR_VHBA_CHANNEL_PROTOCOL_UUID_STR);
 
-struct visor_thread_info {
-	struct task_struct *task;
-	struct completion has_stopped;
-	int id;
-};
-
 struct visordisk_info {
 	u32 valid;
 	u32 channel, id, lun;	/* Disk Path */
@@ -135,7 +131,7 @@ struct visorhba_devdata {
 	struct visordisk_info head;
 	unsigned int max_buff_len;
 	int devnum;
-	struct visor_thread_info threadinfo;
+	struct task_struct *thread;
 	int thread_wait_ms;
 };
 
@@ -152,28 +148,36 @@ static struct visorhba_devices_open visorhbas_open[VISORHBA_OPEN_MAX];
 		    (iter->lun == match->lun))
 /**
  *	visor_thread_start - starts a thread for the device
- *	@thrinfo: The thread to start
  *	@threadfn: Function the thread starts
  *	@thrcontext: Context to pass to the thread, i.e. devdata
  *	@name: string describing name of thread
  *
  *	Starts a thread for the device.
  *
- *	Return 0 on success;
+ *	Return the task_struct * denoting the thread on success,
+ *             or NULL on failure
  */
-static int visor_thread_start(struct visor_thread_info *thrinfo,
-			      int (*threadfn)(void *),
-			      void *thrcontext, char *name)
+static struct task_struct *visor_thread_start
+(int (*threadfn)(void *), void *thrcontext, char *name)
 {
-	/* used to stop the thread */
-	init_completion(&thrinfo->has_stopped);
-	thrinfo->task = kthread_run(threadfn, thrcontext, "%s", name);
-	if (IS_ERR(thrinfo->task)) {
-		thrinfo->id = 0;
-		return PTR_ERR(thrinfo->task);
+	struct task_struct *task;
+
+	task = kthread_run(threadfn, thrcontext, "%s", name);
+	if (IS_ERR(task)) {
+		pr_err("visorbus failed to start thread\n");
+		return NULL;
 	}
-	thrinfo->id = thrinfo->task->pid;
-	return 0;
+	return task;
+}
+
+/**
+ *      visor_thread_stop - stops the thread if it is running
+ */
+static void visor_thread_stop(struct task_struct *task)
+{
+	if (!task)
+		return;  /* no thread running */
+	kthread_stop(task);
 }
 
 /**
@@ -231,16 +235,17 @@ static void *del_scsipending_ent(struct visorhba_devdata *devdata,
 				 int del)
 {
 	unsigned long flags;
-	void *sent = NULL;
+	void *sent;
 
-	if (del < MAX_PENDING_REQUESTS) {
-		spin_lock_irqsave(&devdata->privlock, flags);
-		sent = devdata->pending[del].sent;
+	if (del >= MAX_PENDING_REQUESTS)
+		return NULL;
 
-		devdata->pending[del].cmdtype = 0;
-		devdata->pending[del].sent = NULL;
-		spin_unlock_irqrestore(&devdata->privlock, flags);
-	}
+	spin_lock_irqsave(&devdata->privlock, flags);
+	sent = devdata->pending[del].sent;
+
+	devdata->pending[del].cmdtype = 0;
+	devdata->pending[del].sent = NULL;
+	spin_unlock_irqrestore(&devdata->privlock, flags);
 
 	return sent;
 }
@@ -681,7 +686,7 @@ static void visorhba_serverdown_complete(struct visorhba_devdata *devdata)
 	/* Stop using the IOVM response queue (queue should be drained
 	 * by the end)
 	 */
-	kthread_stop(devdata->threadinfo.task);
+	visor_thread_stop(devdata->thread);
 
 	/* Fail commands that weren't completed */
 	spin_lock_irqsave(&devdata->privlock, flags);
@@ -772,6 +777,24 @@ do_scsi_linuxstat(struct uiscmdrsp *cmdrsp, struct scsi_cmnd *scsicmd)
 	}
 }
 
+static int set_no_disk_inquiry_result(unsigned char *buf,
+				      size_t len, bool is_lun0)
+{
+	if (!buf || len < NO_DISK_INQUIRY_RESULT_LEN)
+		return -EINVAL;
+	memset(buf, 0, NO_DISK_INQUIRY_RESULT_LEN);
+	buf[2] = SCSI_SPC2_VER;
+	if (is_lun0) {
+		buf[0] = DEV_DISK_CAPABLE_NOT_PRESENT;
+		buf[3] = DEV_HISUPPORT;
+	} else {
+		buf[0] = DEV_NOT_CAPABLE;
+	}
+	buf[4] = NO_DISK_INQUIRY_RESULT_LEN - 5;
+	strncpy(buf + 8, "DELLPSEUDO DEVICE .", NO_DISK_INQUIRY_RESULT_LEN - 8);
+	return 0;
+}
+
 /**
  *	do_scsi_nolinuxstat - scsi command didn't have linuxstat
  *	@cmdrsp: response from IOVM
@@ -804,10 +827,8 @@ do_scsi_nolinuxstat(struct uiscmdrsp *cmdrsp, struct scsi_cmnd *scsicmd)
 		 * a disk there so we'll present a processor
 		 * there.
 		 */
-		SET_NO_DISK_INQUIRY_RESULT(buf, cmdrsp->scsi.bufflen,
-					   scsidev->lun,
-					   DEV_DISK_CAPABLE_NOT_PRESENT,
-					   DEV_NOT_CAPABLE);
+		set_no_disk_inquiry_result(buf, (size_t)cmdrsp->scsi.bufflen,
+					   scsidev->lun == 0);
 
 		if (scsi_sg_count(scsicmd) == 0) {
 			memcpy(scsi_sglist(scsicmd), buf,
@@ -929,14 +950,15 @@ static void process_disk_notify(struct Scsi_Host *shost,
 	struct diskaddremove *dar;
 
 	dar = kzalloc(sizeof(*dar), GFP_ATOMIC);
-	if (dar) {
-		dar->add = cmdrsp->disknotify.add;
-		dar->shost = shost;
-		dar->channel = cmdrsp->disknotify.channel;
-		dar->id = cmdrsp->disknotify.id;
-		dar->lun = cmdrsp->disknotify.lun;
-		queue_disk_add_remove(dar);
-	}
+	if (!dar)
+		return;
+
+	dar->add = cmdrsp->disknotify.add;
+	dar->shost = shost;
+	dar->channel = cmdrsp->disknotify.channel;
+	dar->id = cmdrsp->disknotify.id;
+	dar->lun = cmdrsp->disknotify.lun;
+	queue_disk_add_remove(dar);
 }
 
 /**
@@ -1064,8 +1086,8 @@ static int visorhba_resume(struct visor_device *dev,
 	if (devdata->serverdown && !devdata->serverchangingstate)
 		devdata->serverchangingstate = true;
 
-	visor_thread_start(&devdata->threadinfo, process_incoming_rsps,
-			   devdata, "vhba_incming");
+	devdata->thread = visor_thread_start(process_incoming_rsps, devdata,
+					     "vhba_incming");
 
 	devdata->serverdown = false;
 	devdata->serverchangingstate = false;
@@ -1141,8 +1163,8 @@ static int visorhba_probe(struct visor_device *dev)
 		goto err_scsi_remove_host;
 
 	devdata->thread_wait_ms = 2;
-	visor_thread_start(&devdata->threadinfo, process_incoming_rsps,
-			   devdata, "vhba_incoming");
+	devdata->thread = visor_thread_start(process_incoming_rsps, devdata,
+					     "vhba_incoming");
 
 	scsi_scan_host(scsihost);
 
@@ -1172,7 +1194,7 @@ static void visorhba_remove(struct visor_device *dev)
 		return;
 
 	scsihost = devdata->scsihost;
-	kthread_stop(devdata->threadinfo.task);
+	visor_thread_stop(devdata->thread);
 	scsi_remove_host(scsihost);
 	scsi_host_put(scsihost);