Commit 52334f4a authored by Guoqing Jiang's avatar Guoqing Jiang Committed by Jens Axboe
Browse files

rnbd-clt: don't free rsp in msg_open_conf for map scenario 



For map scenario, rsp is freed in two places:

1. msg_open_conf frees rsp if rtrs_clt_request returns 0.

2. Otherwise, rsp is freed by the call sites of rtrs_clt_request.

Now, We'd like to control full lifecycle of rsp in rnbd_clt_map_device,
with that, it is feasible to pass rsp to rnbd_client_setup_device in
next commit.

For 1, it is possible to free rsp from the caller of send_usr_msg
because of the synchronization of iu->comp.wait. And we put iu later
in rnbd_clt_map_device to ensure order of release rsp and iu.

Acked-by: default avatarJack Wang <jinpu.wang@ionos.com>
Signed-off-by: default avatarGuoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-3-guoqing.jiang@linux.dev


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 9ddae3ba

drivers/block/rnbd/rnbd-clt.c

+14 −4
Original line number Diff line number Diff line
@@ -507,6 +507,11 @@ static void msg_open_conf(struct work_struct *work) 
	struct rnbd_msg_open_rsp *rsp = iu->buf;

	struct rnbd_clt_dev *dev = iu->dev;

	int errno = iu->errno;

	bool from_map = false;



	/* INIT state is only triggered from rnbd_clt_map_device */

	if (dev->dev_state == DEV_STATE_INIT)

		from_map = true;



	if (errno) {

		rnbd_clt_err(dev,
@@ -523,6 +528,8 @@ static void msg_open_conf(struct work_struct *work) 
			send_msg_close(dev, device_id, RTRS_PERMIT_NOWAIT);

		}

	}

	/* We free rsp in rnbd_clt_map_device for map scenario */

	if (!from_map)

		kfree(rsp);

	wake_up_iu_comp(iu, errno);

	rnbd_put_iu(dev->sess, iu);
@@ -1617,16 +1624,14 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname, 
	if (ret) {

		rnbd_clt_put_dev(dev);

		rnbd_put_iu(sess, iu);

		kfree(rsp);

	} else {

		ret = errno;

	}

	rnbd_put_iu(sess, iu);

	if (ret) {

		rnbd_clt_err(dev,

			      "map_device: failed, can't open remote device, err: %d\n",

			      ret);

		goto del_dev;

		goto put_iu;

	}

	mutex_lock(&dev->lock);

	pr_debug("Opened remote device: session=%s, path='%s'\n",
@@ -1650,12 +1655,17 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname, 
		       dev->max_hw_sectors, dev->wc, dev->fua);



	mutex_unlock(&dev->lock);

	kfree(rsp);

	rnbd_put_iu(sess, iu);

	rnbd_clt_put_sess(sess);



	return dev;



send_close:

	send_msg_close(dev, dev->device_id, RTRS_PERMIT_WAIT);

put_iu:

	kfree(rsp);

	rnbd_put_iu(sess, iu);

del_dev:

	delete_dev(dev);

put_dev: