1 files changed, 63 insertions, 253 deletions

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 10df39a8b18d..d83fee21f6c5 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -502,34 +502,21 @@ static int blkif_getgeo(struct block_device *bd, struct hd_geometry *hg)
 static int blkif_ioctl(struct block_device *bdev, fmode_t mode,
 		       unsigned command, unsigned long argument)
 {
-	struct blkfront_info *info = bdev->bd_disk->private_data;
 	int i;
 
-	dev_dbg(&info->xbdev->dev, "command: 0x%x, argument: 0x%lx\n",
-		command, (long)argument);
-
 	switch (command) {
 	case CDROMMULTISESSION:
-		dev_dbg(&info->xbdev->dev, "FIXME: support multisession CDs later\n");
 		for (i = 0; i < sizeof(struct cdrom_multisession); i++)
 			if (put_user(0, (char __user *)(argument + i)))
 				return -EFAULT;
 		return 0;
-
-	case CDROM_GET_CAPABILITY: {
-		struct gendisk *gd = info->gd;
-		if (gd->flags & GENHD_FL_CD)
+	case CDROM_GET_CAPABILITY:
+		if (bdev->bd_disk->flags & GENHD_FL_CD)
 			return 0;
 		return -EINVAL;
-	}
-
 	default:
-		/*printk(KERN_ALERT "ioctl %08x not supported by Xen blkdev\n",
-		  command);*/
-		return -EINVAL; /* same return as native Linux */
+		return -EINVAL;
 	}
-
-	return 0;
 }
 
 static unsigned long blkif_ring_get_request(struct blkfront_ring_info *rinfo,
@@ -968,48 +955,6 @@ static void blkif_set_queue_limits(struct blkfront_info *info)
 	blk_queue_dma_alignment(rq, 511);
 }
 
-static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size,
-				unsigned int physical_sector_size)
-{
-	struct request_queue *rq;
-	struct blkfront_info *info = gd->private_data;
-
-	memset(&info->tag_set, 0, sizeof(info->tag_set));
-	info->tag_set.ops = &blkfront_mq_ops;
-	info->tag_set.nr_hw_queues = info->nr_rings;
-	if (HAS_EXTRA_REQ && info->max_indirect_segments == 0) {
-		/*
-		 * When indirect descriptior is not supported, the I/O request
-		 * will be split between multiple request in the ring.
-		 * To avoid problems when sending the request, divide by
-		 * 2 the depth of the queue.
-		 */
-		info->tag_set.queue_depth =  BLK_RING_SIZE(info) / 2;
-	} else
-		info->tag_set.queue_depth = BLK_RING_SIZE(info);
-	info->tag_set.numa_node = NUMA_NO_NODE;
-	info->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
-	info->tag_set.cmd_size = sizeof(struct blkif_req);
-	info->tag_set.driver_data = info;
-
-	if (blk_mq_alloc_tag_set(&info->tag_set))
-		return -EINVAL;
-	rq = blk_mq_init_queue(&info->tag_set);
-	if (IS_ERR(rq)) {
-		blk_mq_free_tag_set(&info->tag_set);
-		return PTR_ERR(rq);
-	}
-
-	rq->queuedata = info;
-	info->rq = gd->queue = rq;
-	info->gd = gd;
-	info->sector_size = sector_size;
-	info->physical_sector_size = physical_sector_size;
-	blkif_set_queue_limits(info);
-
-	return 0;
-}
-
 static const char *flush_info(struct blkfront_info *info)
 {
 	if (info->feature_flush && info->feature_fua)
@@ -1146,12 +1091,36 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 
 	err = xlbd_reserve_minors(minor, nr_minors);
 	if (err)
-		goto out;
+		return err;
 	err = -ENODEV;
 
-	gd = alloc_disk(nr_minors);
-	if (gd == NULL)
-		goto release;
+	memset(&info->tag_set, 0, sizeof(info->tag_set));
+	info->tag_set.ops = &blkfront_mq_ops;
+	info->tag_set.nr_hw_queues = info->nr_rings;
+	if (HAS_EXTRA_REQ && info->max_indirect_segments == 0) {
+		/*
+		 * When indirect descriptior is not supported, the I/O request
+		 * will be split between multiple request in the ring.
+		 * To avoid problems when sending the request, divide by
+		 * 2 the depth of the queue.
+		 */
+		info->tag_set.queue_depth =  BLK_RING_SIZE(info) / 2;
+	} else
+		info->tag_set.queue_depth = BLK_RING_SIZE(info);
+	info->tag_set.numa_node = NUMA_NO_NODE;
+	info->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+	info->tag_set.cmd_size = sizeof(struct blkif_req);
+	info->tag_set.driver_data = info;
+
+	err = blk_mq_alloc_tag_set(&info->tag_set);
+	if (err)
+		goto out_release_minors;
+
+	gd = blk_mq_alloc_disk(&info->tag_set, info);
+	if (IS_ERR(gd)) {
+		err = PTR_ERR(gd);
+		goto out_free_tag_set;
+	}
 
 	strcpy(gd->disk_name, DEV_NAME);
 	ptr = encode_disk_name(gd->disk_name + sizeof(DEV_NAME) - 1, offset);
@@ -1164,14 +1133,16 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 
 	gd->major = XENVBD_MAJOR;
 	gd->first_minor = minor;
+	gd->minors = nr_minors;
 	gd->fops = &xlvbd_block_fops;
 	gd->private_data = info;
 	set_capacity(gd, capacity);
 
-	if (xlvbd_init_blk_queue(gd, sector_size, physical_sector_size)) {
-		del_gendisk(gd);
-		goto release;
-	}
+	info->rq = gd->queue;
+	info->gd = gd;
+	info->sector_size = sector_size;
+	info->physical_sector_size = physical_sector_size;
+	blkif_set_queue_limits(info);
 
 	xlvbd_flush(info);
 
@@ -1186,45 +1157,13 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 
 	return 0;
 
- release:
+out_free_tag_set:
+	blk_mq_free_tag_set(&info->tag_set);
+out_release_minors:
 	xlbd_release_minors(minor, nr_minors);
- out:
 	return err;
 }
 
-static void xlvbd_release_gendisk(struct blkfront_info *info)
-{
-	unsigned int minor, nr_minors, i;
-	struct blkfront_ring_info *rinfo;
-
-	if (info->rq == NULL)
-		return;
-
-	/* No more blkif_request(). */
-	blk_mq_stop_hw_queues(info->rq);
-
-	for_each_rinfo(info, rinfo, i) {
-		/* No more gnttab callback work. */
-		gnttab_cancel_free_callback(&rinfo->callback);
-
-		/* Flush gnttab callback work. Must be done with no locks held. */
-		flush_work(&rinfo->work);
-	}
-
-	del_gendisk(info->gd);
-
-	minor = info->gd->first_minor;
-	nr_minors = info->gd->minors;
-	xlbd_release_minors(minor, nr_minors);
-
-	blk_cleanup_queue(info->rq);
-	blk_mq_free_tag_set(&info->tag_set);
-	info->rq = NULL;
-
-	put_disk(info->gd);
-	info->gd = NULL;
-}
-
 /* Already hold rinfo->ring_lock. */
 static inline void kick_pending_request_queues_locked(struct blkfront_ring_info *rinfo)
 {
@@ -1774,12 +1713,6 @@ abort_transaction:
 	return err;
 }
 
-static void free_info(struct blkfront_info *info)
-{
-	list_del(&info->info_list);
-	kfree(info);
-}
-
 /* Common code used when first setting up, and when resuming. */
 static int talk_to_blkback(struct xenbus_device *dev,
 			   struct blkfront_info *info)
@@ -1898,13 +1831,6 @@ again:
 		xenbus_dev_fatal(dev, err, "%s", message);
  destroy_blkring:
 	blkif_free(info, 0);
-
-	mutex_lock(&blkfront_mutex);
-	free_info(info);
-	mutex_unlock(&blkfront_mutex);
-
-	dev_set_drvdata(&dev->dev, NULL);
-
 	return err;
 }
 
@@ -2144,38 +2070,26 @@ static int blkfront_resume(struct xenbus_device *dev)
 static void blkfront_closing(struct blkfront_info *info)
 {
 	struct xenbus_device *xbdev = info->xbdev;
-	struct block_device *bdev = NULL;
-
-	mutex_lock(&info->mutex);
+	struct blkfront_ring_info *rinfo;
+	unsigned int i;
 
-	if (xbdev->state == XenbusStateClosing) {
-		mutex_unlock(&info->mutex);
+	if (xbdev->state == XenbusStateClosing)
 		return;
-	}
-
-	if (info->gd)
-		bdev = bdgrab(info->gd->part0);
 
-	mutex_unlock(&info->mutex);
-
-	if (!bdev) {
-		xenbus_frontend_closed(xbdev);
-		return;
-	}
+	/* No more blkif_request(). */
+	blk_mq_stop_hw_queues(info->rq);
+	blk_set_queue_dying(info->rq);
+	set_capacity(info->gd, 0);
 
-	mutex_lock(&bdev->bd_mutex);
+	for_each_rinfo(info, rinfo, i) {
+		/* No more gnttab callback work. */
+		gnttab_cancel_free_callback(&rinfo->callback);
 
-	if (bdev->bd_openers) {
-		xenbus_dev_error(xbdev, -EBUSY,
-				 "Device in use; refusing to close");
-		xenbus_switch_state(xbdev, XenbusStateClosing);
-	} else {
-		xlvbd_release_gendisk(info);
-		xenbus_frontend_closed(xbdev);
+		/* Flush gnttab callback work. Must be done with no locks held. */
+		flush_work(&rinfo->work);
 	}
 
-	mutex_unlock(&bdev->bd_mutex);
-	bdput(bdev);
+	xenbus_frontend_closed(xbdev);
 }
 
 static void blkfront_setup_discard(struct blkfront_info *info)
@@ -2490,8 +2404,7 @@ static void blkback_changed(struct xenbus_device *dev,
 			break;
 		fallthrough;
 	case XenbusStateClosing:
-		if (info)
-			blkfront_closing(info);
+		blkfront_closing(info);
 		break;
 	}
 }
@@ -2499,56 +2412,21 @@ static void blkback_changed(struct xenbus_device *dev,
 static int blkfront_remove(struct xenbus_device *xbdev)
 {
 	struct blkfront_info *info = dev_get_drvdata(&xbdev->dev);
-	struct block_device *bdev = NULL;
-	struct gendisk *disk;
 
 	dev_dbg(&xbdev->dev, "%s removed", xbdev->nodename);
 
-	if (!info)
-		return 0;
-
-	blkif_free(info, 0);
-
-	mutex_lock(&info->mutex);
-
-	disk = info->gd;
-	if (disk)
-		bdev = bdgrab(disk->part0);
-
-	info->xbdev = NULL;
-	mutex_unlock(&info->mutex);
-
-	if (!bdev) {
-		mutex_lock(&blkfront_mutex);
-		free_info(info);
-		mutex_unlock(&blkfront_mutex);
-		return 0;
-	}
-
-	/*
-	 * The xbdev was removed before we reached the Closed
-	 * state. See if it's safe to remove the disk. If the bdev
-	 * isn't closed yet, we let release take care of it.
-	 */
-
-	mutex_lock(&bdev->bd_mutex);
-	info = disk->private_data;
-
-	dev_warn(disk_to_dev(disk),
-		 "%s was hot-unplugged, %d stale handles\n",
-		 xbdev->nodename, bdev->bd_openers);
+	del_gendisk(info->gd);
 
-	if (info && !bdev->bd_openers) {
-		xlvbd_release_gendisk(info);
-		disk->private_data = NULL;
-		mutex_lock(&blkfront_mutex);
-		free_info(info);
-		mutex_unlock(&blkfront_mutex);
-	}
+	mutex_lock(&blkfront_mutex);
+	list_del(&info->info_list);
+	mutex_unlock(&blkfront_mutex);
 
-	mutex_unlock(&bdev->bd_mutex);
-	bdput(bdev);
+	blkif_free(info, 0);
+	xlbd_release_minors(info->gd->first_minor, info->gd->minors);
+	blk_cleanup_disk(info->gd);
+	blk_mq_free_tag_set(&info->tag_set);
 
+	kfree(info);
 	return 0;
 }
 
@@ -2559,77 +2437,9 @@ static int blkfront_is_ready(struct xenbus_device *dev)
 	return info->is_ready && info->xbdev;
 }
 
-static int blkif_open(struct block_device *bdev, fmode_t mode)
-{
-	struct gendisk *disk = bdev->bd_disk;
-	struct blkfront_info *info;
-	int err = 0;
-
-	mutex_lock(&blkfront_mutex);
-
-	info = disk->private_data;
-	if (!info) {
-		/* xbdev gone */
-		err = -ERESTARTSYS;
-		goto out;
-	}
-
-	mutex_lock(&info->mutex);
-
-	if (!info->gd)
-		/* xbdev is closed */
-		err = -ERESTARTSYS;
-
-	mutex_unlock(&info->mutex);
-
-out:
-	mutex_unlock(&blkfront_mutex);
-	return err;
-}
-
-static void blkif_release(struct gendisk *disk, fmode_t mode)
-{
-	struct blkfront_info *info = disk->private_data;
-	struct xenbus_device *xbdev;
-
-	mutex_lock(&blkfront_mutex);
-	if (disk->part0->bd_openers)
-		goto out_mutex;
-
-	/*
-	 * Check if we have been instructed to close. We will have
-	 * deferred this request, because the bdev was still open.
-	 */
-
-	mutex_lock(&info->mutex);
-	xbdev = info->xbdev;
-
-	if (xbdev && xbdev->state == XenbusStateClosing) {
-		/* pending switch to state closed */
-		dev_info(disk_to_dev(disk), "releasing disk\n");
-		xlvbd_release_gendisk(info);
-		xenbus_frontend_closed(info->xbdev);
- 	}
-
-	mutex_unlock(&info->mutex);
-
-	if (!xbdev) {
-		/* sudden device removal */
-		dev_info(disk_to_dev(disk), "releasing disk\n");
-		xlvbd_release_gendisk(info);
-		disk->private_data = NULL;
-		free_info(info);
-	}
-
-out_mutex:
-	mutex_unlock(&blkfront_mutex);
-}
-
 static const struct block_device_operations xlvbd_block_fops =
 {
 	.owner = THIS_MODULE,
-	.open = blkif_open,
-	.release = blkif_release,
 	.getgeo = blkif_getgeo,
 	.ioctl = blkif_ioctl,
 	.compat_ioctl = blkdev_compat_ptr_ioctl,