diff options
| -rw-r--r-- | drivers/block/xen-blkfront.c | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 1e406f0..763a315 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -1118,16 +1118,33 @@ static int blkfront_is_ready(struct xenbus_device *dev) static int blkif_open(struct block_device *bdev, fmode_t mode) { - struct blkfront_info *info = bdev->bd_disk->private_data; - - if (!info->xbdev) - return -ENODEV; + struct gendisk *disk = bdev->bd_disk; + struct blkfront_info *info; + int err = 0; lock_kernel(); - info->users++; - unlock_kernel(); - return 0; + 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); + + if (!err) + ++info->users; + + unlock_kernel(); +out: + return err; } static int blkif_release(struct gendisk *disk, fmode_t mode) |
