[SCSI] fix scsi_reap_target() device_del from atomic context
scsi_reap_target() was desgined to be called from any context.
However it must do a device_del() of the target device, which may only
be called from user context. Thus we have to reimplement
scsi_reap_target() via a workqueue.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 94e5167f..e36c21e 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -400,6 +400,35 @@
return found_target;
}
+struct work_queue_wrapper {
+ struct work_struct work;
+ struct scsi_target *starget;
+};
+
+static void scsi_target_reap_work(void *data) {
+ struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;
+ struct scsi_target *starget = wqw->starget;
+ struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
+ unsigned long flags;
+
+ kfree(wqw);
+
+ spin_lock_irqsave(shost->host_lock, flags);
+
+ if (--starget->reap_ref == 0 && list_empty(&starget->devices)) {
+ list_del_init(&starget->siblings);
+ spin_unlock_irqrestore(shost->host_lock, flags);
+ device_del(&starget->dev);
+ transport_unregister_device(&starget->dev);
+ put_device(&starget->dev);
+ return;
+
+ }
+ spin_unlock_irqrestore(shost->host_lock, flags);
+
+ return;
+}
+
/**
* scsi_target_reap - check to see if target is in use and destroy if not
*
@@ -411,19 +440,18 @@
*/
void scsi_target_reap(struct scsi_target *starget)
{
- struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
- unsigned long flags;
- spin_lock_irqsave(shost->host_lock, flags);
+ struct work_queue_wrapper *wqw =
+ kzalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
- if (--starget->reap_ref == 0 && list_empty(&starget->devices)) {
- list_del_init(&starget->siblings);
- spin_unlock_irqrestore(shost->host_lock, flags);
- device_del(&starget->dev);
- transport_unregister_device(&starget->dev);
- put_device(&starget->dev);
+ if (!wqw) {
+ starget_printk(KERN_ERR, starget,
+ "Failed to allocate memory in scsi_reap_target()\n");
return;
}
- spin_unlock_irqrestore(shost->host_lock, flags);
+
+ INIT_WORK(&wqw->work, scsi_target_reap_work, wqw);
+ wqw->starget = starget;
+ schedule_work(&wqw->work);
}
/**
