[MTD] Finish conversion mtd_blkdevs to use the kthread API

Remove waitqueue, 'exiting' flag and completion; use kthread APIs instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 9 insertions, 23 deletions

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 1aa018abd332..524b83b5ebf5 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -29,9 +29,7 @@ extern struct mutex mtd_table_mutex;
 extern struct mtd_info *mtd_table[];
 
 struct mtd_blkcore_priv {
-        struct completion thread_dead;
-        int exiting;
-        wait_queue_head_t thread_wq;
+        struct task_struct *thread;
         struct request_queue *rq;
         spinlock_t queue_lock;
 };
@@ -85,26 +83,18 @@ static int mtd_blktrans_thread(void *arg)
         current->flags |= PF_MEMALLOC | PF_NOFREEZE;
 
         spin_lock_irq(rq->queue_lock);
-
-        while (!tr->blkcore_priv->exiting) {
+        while (!kthread_should_stop()) {
                 struct request *req;
                 struct mtd_blktrans_dev *dev;
                 int res = 0;
-                DECLARE_WAITQUEUE(wait, current);
 
                 req = elv_next_request(rq);
 
                 if (!req) {
-                        add_wait_queue(&tr->blkcore_priv->thread_wq, &wait);
                         set_current_state(TASK_INTERRUPTIBLE);
-
                         spin_unlock_irq(rq->queue_lock);
-
                         schedule();
-                        remove_wait_queue(&tr->blkcore_priv->thread_wq, &wait);
-
                         spin_lock_irq(rq->queue_lock);
-
                         continue;
                 }
 
@@ -123,13 +113,13 @@ static int mtd_blktrans_thread(void *arg)
         }
         spin_unlock_irq(rq->queue_lock);
 
-        complete_and_exit(&tr->blkcore_priv->thread_dead, 0);
+        return 0;
 }
 
 static void mtd_blktrans_request(struct request_queue *rq)
 {
         struct mtd_blktrans_ops *tr = rq->queuedata;
-        wake_up(&tr->blkcore_priv->thread_wq);
+        wake_up_process(tr->blkcore_priv->thread);
 }
 
 
@@ -355,7 +345,6 @@ static struct mtd_notifier blktrans_notifier = {
 
 int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
 {
-        struct task_struct *task;
         int ret, i;
 
         /* Register the notifier if/when the first device type is
@@ -379,8 +368,6 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
                 return ret;
         }
         spin_lock_init(&tr->blkcore_priv->queue_lock);
-        init_completion(&tr->blkcore_priv->thread_dead);
-        init_waitqueue_head(&tr->blkcore_priv->thread_wq);
 
         tr->blkcore_priv->rq = blk_init_queue(mtd_blktrans_request, &tr->blkcore_priv->queue_lock);
         if (!tr->blkcore_priv->rq) {
@@ -394,13 +381,14 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
         blk_queue_hardsect_size(tr->blkcore_priv->rq, tr->blksize);
         tr->blkshift = ffs(tr->blksize) - 1;
 
-        task = kthread_run(mtd_blktrans_thread, tr, "%sd", tr->name);
-        if (IS_ERR(task)) {
+        tr->blkcore_priv->thread = kthread_run(mtd_blktrans_thread, tr,
+                        "%sd", tr->name);
+        if (IS_ERR(tr->blkcore_priv->thread)) {
                 blk_cleanup_queue(tr->blkcore_priv->rq);
                 unregister_blkdev(tr->major, tr->name);
                 kfree(tr->blkcore_priv);
                 mutex_unlock(&mtd_table_mutex);
-                return PTR_ERR(task);
+                return PTR_ERR(tr->blkcore_priv->thread);
         }
 
         INIT_LIST_HEAD(&tr->devs);
@@ -423,9 +411,7 @@ int deregister_mtd_blktrans(struct mtd_blktrans_ops *tr)
         mutex_lock(&mtd_table_mutex);
 
         /* Clean up the kernel thread */
-        tr->blkcore_priv->exiting = 1;
-        wake_up(&tr->blkcore_priv->thread_wq);
-        wait_for_completion(&tr->blkcore_priv->thread_dead);
+        kthread_stop(tr->blkcore_priv->thread);
 
         /* Remove it from the list of active majors */
         list_del(&tr->list);