1 files changed, 197 insertions, 45 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 4c95b503b09e..bbeb404b3a07 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -541,7 +541,6 @@ static int rbd_open(struct block_device *bdev, fmode_t mode)
 		return -ENOENT;
 
 	(void) get_device(&rbd_dev->dev);
-	set_device_ro(bdev, rbd_dev->mapping.read_only);
 
 	return 0;
 }
@@ -559,10 +558,76 @@ static void rbd_release(struct gendisk *disk, fmode_t mode)
 	put_device(&rbd_dev->dev);
 }
 
+static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
+{
+	int ret = 0;
+	int val;
+	bool ro;
+	bool ro_changed = false;
+
+	/* get_user() may sleep, so call it before taking rbd_dev->lock */
+	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;
+
+	spin_lock_irq(&rbd_dev->lock);
+	/* prevent others open this device */
+	if (rbd_dev->open_count > 1) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	if (rbd_dev->mapping.read_only != ro) {
+		rbd_dev->mapping.read_only = ro;
+		ro_changed = true;
+	}
+
+out:
+	spin_unlock_irq(&rbd_dev->lock);
+	/* set_disk_ro() may sleep, so call it after releasing rbd_dev->lock */
+	if (ret == 0 && ro_changed)
+		set_disk_ro(rbd_dev->disk, ro ? 1 : 0);
+
+	return ret;
+}
+
+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;
+
+	switch (cmd) {
+	case BLKROSET:
+		ret = rbd_ioctl_set_ro(rbd_dev, arg);
+		break;
+	default:
+		ret = -ENOTTY;
+	}
+
+	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
 };
 
 /*
@@ -1382,6 +1447,13 @@ static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
 	kref_put(&obj_request->kref, rbd_obj_request_destroy);
 }
 
+static void rbd_img_request_get(struct rbd_img_request *img_request)
+{
+	dout("%s: img %p (was %d)\n", __func__, img_request,
+	     atomic_read(&img_request->kref.refcount));
+	kref_get(&img_request->kref);
+}
+
 static bool img_request_child_test(struct rbd_img_request *img_request);
 static void rbd_parent_request_destroy(struct kref *kref);
 static void rbd_img_request_destroy(struct kref *kref);
@@ -2142,6 +2214,7 @@ static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
 	img_request->next_completion = which;
 out:
 	spin_unlock_irq(&img_request->completion_lock);
+	rbd_img_request_put(img_request);
 
 	if (!more)
 		rbd_img_request_complete(img_request);
@@ -2242,6 +2315,7 @@ static int rbd_img_request_fill(struct rbd_img_request *img_request,
 			goto out_unwind;
 		obj_request->osd_req = osd_req;
 		obj_request->callback = rbd_img_obj_callback;
+		rbd_img_request_get(img_request);
 
 		if (write_request) {
 			osd_req_op_alloc_hint_init(osd_req, which,
@@ -2872,56 +2946,55 @@ static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
 }
 
 /*
- * Request sync osd watch/unwatch.  The value of "start" determines
- * whether a watch request is being initiated or torn down.
+ * Initiate a watch request, synchronously.
  */
-static int __rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start)
+static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev)
 {
 	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
 	struct rbd_obj_request *obj_request;
 	int ret;
 
-	rbd_assert(start ^ !!rbd_dev->watch_event);
-	rbd_assert(start ^ !!rbd_dev->watch_request);
+	rbd_assert(!rbd_dev->watch_event);
+	rbd_assert(!rbd_dev->watch_request);
 
-	if (start) {
-		ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
-						&rbd_dev->watch_event);
-		if (ret < 0)
-			return ret;
-		rbd_assert(rbd_dev->watch_event != NULL);
-	}
+	ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
+				     &rbd_dev->watch_event);
+	if (ret < 0)
+		return ret;
+
+	rbd_assert(rbd_dev->watch_event);
 
-	ret = -ENOMEM;
 	obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
-							OBJ_REQUEST_NODATA);
-	if (!obj_request)
+					     OBJ_REQUEST_NODATA);
+	if (!obj_request) {
+		ret = -ENOMEM;
 		goto out_cancel;
+	}
 
 	obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1,
 						  obj_request);
-	if (!obj_request->osd_req)
-		goto out_cancel;
+	if (!obj_request->osd_req) {
+		ret = -ENOMEM;
+		goto out_put;
+	}
 
-	if (start)
-		ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
-	else
-		ceph_osdc_unregister_linger_request(osdc,
-					rbd_dev->watch_request->osd_req);
+	ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
 
 	osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
-				rbd_dev->watch_event->cookie, 0, start ? 1 : 0);
+			      rbd_dev->watch_event->cookie, 0, 1);
 	rbd_osd_req_format_write(obj_request);
 
 	ret = rbd_obj_request_submit(osdc, obj_request);
 	if (ret)
-		goto out_cancel;
+		goto out_linger;
+
 	ret = rbd_obj_request_wait(obj_request);
 	if (ret)
-		goto out_cancel;
+		goto out_linger;
+
 	ret = obj_request->result;
 	if (ret)
-		goto out_cancel;
+		goto out_linger;
 
 	/*
 	 * A watch request is set to linger, so the underlying osd
@@ -2931,36 +3004,84 @@ static int __rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start)
 	 * it.  We'll drop that reference (below) after we've
 	 * unregistered it.
 	 */
-	if (start) {
-		rbd_dev->watch_request = obj_request;
+	rbd_dev->watch_request = obj_request;
 
-		return 0;
+	return 0;
+
+out_linger:
+	ceph_osdc_unregister_linger_request(osdc, obj_request->osd_req);
+out_put:
+	rbd_obj_request_put(obj_request);
+out_cancel:
+	ceph_osdc_cancel_event(rbd_dev->watch_event);
+	rbd_dev->watch_event = NULL;
+
+	return ret;
+}
+
+/*
+ * Tear down a watch request, synchronously.
+ */
+static int __rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev)
+{
+	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
+	struct rbd_obj_request *obj_request;
+	int ret;
+
+	rbd_assert(rbd_dev->watch_event);
+	rbd_assert(rbd_dev->watch_request);
+
+	obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
+					     OBJ_REQUEST_NODATA);
+	if (!obj_request) {
+		ret = -ENOMEM;
+		goto out_cancel;
+	}
+
+	obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1,
+						  obj_request);
+	if (!obj_request->osd_req) {
+		ret = -ENOMEM;
+		goto out_put;
 	}
 
+	osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
+			      rbd_dev->watch_event->cookie, 0, 0);
+	rbd_osd_req_format_write(obj_request);
+
+	ret = rbd_obj_request_submit(osdc, obj_request);
+	if (ret)
+		goto out_put;
+
+	ret = rbd_obj_request_wait(obj_request);
+	if (ret)
+		goto out_put;
+
+	ret = obj_request->result;
+	if (ret)
+		goto out_put;
+
 	/* We have successfully torn down the watch request */
 
+	ceph_osdc_unregister_linger_request(osdc,
+					    rbd_dev->watch_request->osd_req);
 	rbd_obj_request_put(rbd_dev->watch_request);
 	rbd_dev->watch_request = NULL;
+
+out_put:
+	rbd_obj_request_put(obj_request);
 out_cancel:
-	/* Cancel the event if we're tearing down, or on error */
 	ceph_osdc_cancel_event(rbd_dev->watch_event);
 	rbd_dev->watch_event = NULL;
-	if (obj_request)
-		rbd_obj_request_put(obj_request);
 
 	return ret;
 }
 
-static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev)
-{
-	return __rbd_dev_header_watch_sync(rbd_dev, true);
-}
-
 static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev)
 {
 	int ret;
 
-	ret = __rbd_dev_header_watch_sync(rbd_dev, false);
+	ret = __rbd_dev_header_unwatch_sync(rbd_dev);
 	if (ret) {
 		rbd_warn(rbd_dev, "unable to tear down watch request: %d\n",
 			 ret);
@@ -3058,7 +3179,6 @@ static void rbd_request_fn(struct request_queue *q)
 		__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;
 
@@ -3094,7 +3214,7 @@ static void rbd_request_fn(struct request_queue *q)
 
 		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);
 		}
@@ -4683,6 +4803,38 @@ out_err:
 }
 
 /*
+ * Return pool id (>= 0) or a negative error code.
+ */
+static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name)
+{
+	u64 newest_epoch;
+	unsigned long timeout = rbdc->client->options->mount_timeout * HZ;
+	int tries = 0;
+	int ret;
+
+again:
+	ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name);
+	if (ret == -ENOENT && tries++ < 1) {
+		ret = ceph_monc_do_get_version(&rbdc->client->monc, "osdmap",
+					       &newest_epoch);
+		if (ret < 0)
+			return ret;
+
+		if (rbdc->client->osdc.osdmap->epoch < newest_epoch) {
+			ceph_monc_request_next_osdmap(&rbdc->client->monc);
+			(void) ceph_monc_wait_osdmap(&rbdc->client->monc,
+						     newest_epoch, timeout);
+			goto again;
+		} else {
+			/* the osdmap we have is new enough */
+			return -ENOENT;
+		}
+	}
+
+	return ret;
+}
+
+/*
  * An rbd format 2 image has a unique identifier, distinct from the
  * name given to it by the user.  Internally, that identifier is
  * what's used to specify the names of objects related to the image.
@@ -4752,7 +4904,7 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev)
 
 		image_id = ceph_extract_encoded_string(&p, p + ret,
 						NULL, GFP_NOIO);
-		ret = IS_ERR(image_id) ? PTR_ERR(image_id) : 0;
+		ret = PTR_ERR_OR_ZERO(image_id);
 		if (!ret)
 			rbd_dev->image_format = 2;
 	} else {
@@ -4907,6 +5059,7 @@ static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
 	if (ret)
 		goto err_out_disk;
 	set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
+	set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only);
 
 	ret = rbd_bus_add_dev(rbd_dev);
 	if (ret)
@@ -5053,7 +5206,6 @@ static ssize_t do_rbd_add(struct bus_type *bus,
 	struct rbd_options *rbd_opts = NULL;
 	struct rbd_spec *spec = NULL;
 	struct rbd_client *rbdc;
-	struct ceph_osd_client *osdc;
 	bool read_only;
 	int rc = -ENOMEM;
 
@@ -5075,8 +5227,7 @@ static ssize_t do_rbd_add(struct bus_type *bus,
 	}
 
 	/* pick the pool */
-	osdc = &rbdc->client->osdc;
-	rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
+	rc = rbd_add_get_pool_id(rbdc, spec->pool_name);
 	if (rc < 0)
 		goto err_out_client;
 	spec->pool_id = (u64)rc;
@@ -5387,6 +5538,7 @@ err_out_slab:
 
 static void __exit rbd_exit(void)
 {
+	ida_destroy(&rbd_dev_id_ida);
 	rbd_sysfs_cleanup();
 	if (single_major)
 		unregister_blkdev(rbd_major, RBD_DRV_NAME);