[SCSI] fix wrong context bugs in SCSI

There's a bug in releasing scsi_device where the release function
actually frees the block queue.  However, the block queue release
calls flush_work(), which requires process context (the scsi_device
structure may release from irq context).  Update the release function
to invoke via the execute_in_process_context() API.

Also clean up the scsi_target structure releasing via this API.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

2 files changed, 12 insertions, 23 deletions

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 752fb5da3de4..5acb83ca5ae5 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -387,19 +387,12 @@ static struct scsi_target *scsi_alloc_target(struct device *parent,
         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;
+static void scsi_target_reap_usercontext(void *data)
+{
+        struct scsi_target *starget = data;
         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)) {
@@ -428,18 +421,7 @@ static void scsi_target_reap_work(void *data) {
  */
 void scsi_target_reap(struct scsi_target *starget)
 {
-        struct work_queue_wrapper *wqw = 
-                kzalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
-
-        if (!wqw) {
-                starget_printk(KERN_ERR, starget,
-                               "Failed to allocate memory in scsi_reap_target()\n");
-                return;
-        }
-
-        INIT_WORK(&wqw->work, scsi_target_reap_work, wqw);
-        wqw->starget = starget;
-        schedule_work(&wqw->work);
+        scsi_execute_in_process_context(scsi_target_reap_usercontext, starget);
 }
 
 /**
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index a77b32deaf8f..902a5def8e62 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -217,8 +217,9 @@ static void scsi_device_cls_release(struct class_device *class_dev)
         put_device(&sdev->sdev_gendev);
 }
 
-static void scsi_device_dev_release(struct device *dev)
+static void scsi_device_dev_release_usercontext(void *data)
 {
+        struct device *dev = data;
         struct scsi_device *sdev;
         struct device *parent;
         struct scsi_target *starget;
@@ -237,6 +238,7 @@ static void scsi_device_dev_release(struct device *dev)
 
         if (sdev->request_queue) {
                 sdev->request_queue->queuedata = NULL;
+                /* user context needed to free queue */
                 scsi_free_queue(sdev->request_queue);
                 /* temporary expedient, try to catch use of queue lock
                  * after free of sdev */
@@ -252,6 +254,11 @@ static void scsi_device_dev_release(struct device *dev)
                 put_device(parent);
 }
 
+static void scsi_device_dev_release(struct device *dev)
+{
+        scsi_execute_in_process_context(scsi_device_dev_release_usercontext,    dev);
+}
+
 static struct class sdev_class = {
         .name           = "scsi_device",
         .release        = scsi_device_cls_release,