rbd: add ioctl for rbd
When running the following commands:
[root@ceph0 mnt]# blockdev --setro /dev/rbd1
[root@ceph0 mnt]# blockdev --getro /dev/rbd1
0
The block setro didn't take effect, it is because
the rbd doesn't support ioctl of block driver.
This resolves:
http://tracker.ceph.com/issues/6265
Signed-off-by: Guangliang Zhao <guangliang@unitedstack.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 8295b3a..1c88fba 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -559,10 +559,69 @@
put_device(&rbd_dev->dev);
}
+static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
+{
+ int val;
+ bool ro;
+
+ if (get_user(val, (int __user *)(arg)))
+ return -EFAULT;
+
+ ro = val ? true : false;
+ /* Snapshot doesn't allow to write*/
+ if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro)
+ return -EROFS;
+
+ if (rbd_dev->mapping.read_only != ro) {
+ rbd_dev->mapping.read_only = ro;
+ set_disk_ro(rbd_dev->disk, ro ? 1 : 0);
+ }
+
+ return 0;
+}
+
+static int rbd_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long arg)
+{
+ struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
+ int ret = 0;
+
+ spin_lock_irq(&rbd_dev->lock);
+ /* prevent others open this device */
+ if (rbd_dev->open_count > 1) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ switch (cmd) {
+ case BLKROSET:
+ ret = rbd_ioctl_set_ro(rbd_dev, arg);
+ break;
+ default:
+ ret = -ENOTTY;
+ }
+
+out:
+ spin_unlock_irq(&rbd_dev->lock);
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long arg)
+{
+ return rbd_ioctl(bdev, mode, cmd, arg);
+}
+#endif /* CONFIG_COMPAT */
+
static const struct block_device_operations rbd_bd_ops = {
.owner = THIS_MODULE,
.open = rbd_open,
.release = rbd_release,
+ .ioctl = rbd_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = rbd_compat_ioctl,
+#endif
};
/*
@@ -3114,7 +3173,6 @@
__releases(q->queue_lock) __acquires(q->queue_lock)
{
struct rbd_device *rbd_dev = q->queuedata;
- bool read_only = rbd_dev->mapping.read_only;
struct request *rq;
int result;
@@ -3150,7 +3208,7 @@
if (write_request) {
result = -EROFS;
- if (read_only)
+ if (rbd_dev->mapping.read_only)
goto end_request;
rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
}