rnbd-clt: open code send_msg_open in rnbd_clt_map_device

Let's open code it in rnbd_clt_map_device, then we can use information
from rsp to setup gendisk and request_queue in next commits. After that,
we can remove some members (wc, fua and max_hw_sectors etc) from struct
rnbd_clt_dev.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-2-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index b8d9e28..00d26e4 100644 (file)
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1562,7 +1562,14 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 {
        struct rnbd_clt_session *sess;
        struct rnbd_clt_dev *dev;
-       int ret;
+       int ret, errno;
+       struct rnbd_msg_open_rsp *rsp;
+       struct rnbd_msg_open msg;
+       struct rnbd_iu *iu;
+       struct kvec vec = {
+               .iov_base = &msg,
+               .iov_len  = sizeof(msg)
+       };
 
        if (exists_devpath(pathname, sessname))
                return ERR_PTR(-EEXIST);
@@ -1582,7 +1589,39 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
                ret = -EEXIST;
                goto put_dev;
        }
-       ret = send_msg_open(dev, RTRS_PERMIT_WAIT);
+
+       rsp = kzalloc(sizeof(*rsp), GFP_KERNEL);
+       if (!rsp) {
+               ret = -ENOMEM;
+               goto del_dev;
+       }
+
+       iu = rnbd_get_iu(sess, RTRS_ADMIN_CON, RTRS_PERMIT_WAIT);
+       if (!iu) {
+               ret = -ENOMEM;
+               kfree(rsp);
+               goto del_dev;
+       }
+       iu->buf = rsp;
+       iu->dev = dev;
+       sg_init_one(iu->sgt.sgl, rsp, sizeof(*rsp));
+
+       msg.hdr.type    = cpu_to_le16(RNBD_MSG_OPEN);
+       msg.access_mode = dev->access_mode;
+       strscpy(msg.dev_name, dev->pathname, sizeof(msg.dev_name));
+
+       WARN_ON(!rnbd_clt_get_dev(dev));
+       ret = send_usr_msg(sess->rtrs, READ, iu,
+                          &vec, sizeof(*rsp), iu->sgt.sgl, 1,
+                          msg_open_conf, &errno, RTRS_PERMIT_WAIT);
+       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",