X-Git-Url: http://bbs.cooldavid.org/git/?a=blobdiff_plain;f=drivers%2Fmtd%2Fmtd_blkdevs.c;h=f9329794f3b554936f13fda170ddb0d16eb9bc57;hb=67577927e8d7a1f4b09b4992df640eadc6aacb36;hp=62e68707b07f49a6f07a8f97a7333880f9d7f1db;hpb=b171aa27700c78511086a759383b033949c9d7f0;p=net-next-2.6.git

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 62e68707b07..f9329794f3b 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -29,7 +29,6 @@
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
 #include <linux/spinlock.h>
-#include <linux/smp_lock.h>
 #include <linux/hdreg.h>
 #include <linux/init.h>
 #include <linux/mutex.h>
@@ -38,6 +37,7 @@
 
 #include "mtdcore.h"
 
+static DEFINE_MUTEX(mtd_blkdevs_mutex);
 static LIST_HEAD(blktrans_majors);
 static DEFINE_MUTEX(blktrans_ref_mutex);
 
@@ -133,6 +133,10 @@ static int mtd_blktrans_thread(void *arg)
 
 		if (!req && !(req = blk_fetch_request(rq))) {
 			set_current_state(TASK_INTERRUPTIBLE);
+
+			if (kthread_should_stop())
+				set_current_state(TASK_RUNNING);
+
 			spin_unlock_irq(rq->queue_lock);
 			schedule();
 			spin_lock_irq(rq->queue_lock);
@@ -176,54 +180,57 @@ static void mtd_blktrans_request(struct request_queue *rq)
 static int blktrans_open(struct block_device *bdev, fmode_t mode)
 {
 	struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk);
-	int ret;
+	int ret = 0;
 
 	if (!dev)
 		return -ERESTARTSYS; /* FIXME: busy loop! -arnd*/
 
-	lock_kernel();
+	mutex_lock(&mtd_blkdevs_mutex);
 	mutex_lock(&dev->lock);
 
-	if (!dev->mtd) {
-		ret = -ENXIO;
+	if (dev->open++)
 		goto unlock;
-	}
 
-	ret = !dev->open++ && dev->tr->open ? dev->tr->open(dev) : 0;
+	kref_get(&dev->ref);
+	__module_get(dev->tr->owner);
+
+	if (dev->mtd) {
+		ret = dev->tr->open ? dev->tr->open(dev) : 0;
+		__get_mtd_device(dev->mtd);
+	}
 
-	/* Take another reference on the device so it won't go away till
-		last release */
-	if (!ret)
-		kref_get(&dev->ref);
 unlock:
 	mutex_unlock(&dev->lock);
 	blktrans_dev_put(dev);
-	unlock_kernel();
+	mutex_unlock(&mtd_blkdevs_mutex);
 	return ret;
 }
 
 static int blktrans_release(struct gendisk *disk, fmode_t mode)
 {
 	struct mtd_blktrans_dev *dev = blktrans_dev_get(disk);
-	int ret = -ENXIO;
+	int ret = 0;
 
 	if (!dev)
 		return ret;
 
-	lock_kernel();
+	mutex_lock(&mtd_blkdevs_mutex);
 	mutex_lock(&dev->lock);
 
-	/* Release one reference, we sure its not the last one here*/
-	kref_put(&dev->ref, blktrans_dev_release);
-
-	if (!dev->mtd)
+	if (--dev->open)
 		goto unlock;
 
-	ret = !--dev->open && dev->tr->release ? dev->tr->release(dev) : 0;
+	kref_put(&dev->ref, blktrans_dev_release);
+	module_put(dev->tr->owner);
+
+	if (dev->mtd) {
+		ret = dev->tr->release ? dev->tr->release(dev) : 0;
+		__put_mtd_device(dev->mtd);
+	}
 unlock:
 	mutex_unlock(&dev->lock);
 	blktrans_dev_put(dev);
-	unlock_kernel();
+	mutex_unlock(&mtd_blkdevs_mutex);
 	return ret;
 }
 
@@ -256,7 +263,7 @@ static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
 	if (!dev)
 		return ret;
 
-	lock_kernel();
+	mutex_lock(&mtd_blkdevs_mutex);
 	mutex_lock(&dev->lock);
 
 	if (!dev->mtd)
@@ -271,7 +278,7 @@ static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
 	}
 unlock:
 	mutex_unlock(&dev->lock);
-	unlock_kernel();
+	mutex_unlock(&mtd_blkdevs_mutex);
 	blktrans_dev_put(dev);
 	return ret;
 }
@@ -385,9 +392,6 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 
 	gd->queue = new->rq;
 
-	__get_mtd_device(new->mtd);
-	__module_get(tr->owner);
-
 	/* Create processing thread */
 	/* TODO: workqueue ? */
 	new->thread = kthread_run(mtd_blktrans_thread, new,
@@ -410,8 +414,6 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 	}
 	return 0;
 error4:
-	module_put(tr->owner);
-	__put_mtd_device(new->mtd);
 	blk_cleanup_queue(new->rq);
 error3:
 	put_disk(new->disk);
@@ -448,17 +450,15 @@ int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old)
 	blk_start_queue(old->rq);
 	spin_unlock_irqrestore(&old->queue_lock, flags);
 
-	/* Ask trans driver for release to the mtd device */
+	/* If the device is currently open, tell trans driver to close it,
+		then put mtd device, and don't touch it again */
 	mutex_lock(&old->lock);
-	if (old->open && old->tr->release) {
-		old->tr->release(old);
-		old->open = 0;
+	if (old->open) {
+		if (old->tr->release)
+			old->tr->release(old);
+		__put_mtd_device(old->mtd);
 	}
 
-	__put_mtd_device(old->mtd);
-	module_put(old->tr->owner);
-
-	/* At that point, we don't touch the mtd anymore */
 	old->mtd = NULL;
 
 	mutex_unlock(&old->lock);
@@ -508,13 +508,16 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
 	mutex_lock(&mtd_table_mutex);
 
 	ret = register_blkdev(tr->major, tr->name);
-	if (ret) {
+	if (ret < 0) {
 		printk(KERN_WARNING "Unable to register %s block device on major %d: %d\n",
 		       tr->name, tr->major, ret);
 		mutex_unlock(&mtd_table_mutex);
 		return ret;
 	}
 
+	if (ret)
+		tr->major = ret;
+
 	tr->blkshift = ffs(tr->blksize) - 1;
 
 	INIT_LIST_HEAD(&tr->devs);