1 files changed, 24 insertions, 26 deletions

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 39e5f7fae3ef..83a7ba4a3eec 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -230,29 +230,40 @@ static int nbd_send_req(struct nbd_device *nbd, struct request *req)
         int result, flags;
         struct nbd_request request;
         unsigned long size = blk_rq_bytes(req);
+        u32 type;
+
+        if (req->cmd_type == REQ_TYPE_DRV_PRIV)
+                type = NBD_CMD_DISC;
+        else if (req->cmd_flags & REQ_DISCARD)
+                type = NBD_CMD_TRIM;
+        else if (req->cmd_flags & REQ_FLUSH)
+                type = NBD_CMD_FLUSH;
+        else if (rq_data_dir(req) == WRITE)
+                type = NBD_CMD_WRITE;
+        else
+                type = NBD_CMD_READ;
 
         memset(&request, 0, sizeof(request));
         request.magic = htonl(NBD_REQUEST_MAGIC);
-        request.type = htonl(nbd_cmd(req));
-
-        if (nbd_cmd(req) != NBD_CMD_FLUSH && nbd_cmd(req) != NBD_CMD_DISC) {
+        request.type = htonl(type);
+        if (type != NBD_CMD_FLUSH && type != NBD_CMD_DISC) {
                 request.from = cpu_to_be64((u64)blk_rq_pos(req) << 9);
                 request.len = htonl(size);
         }
         memcpy(request.handle, &req, sizeof(req));
 
         dev_dbg(nbd_to_dev(nbd), "request %p: sending control (%s@%llu,%uB)\n",
-                req, nbdcmd_to_ascii(nbd_cmd(req)),
+                req, nbdcmd_to_ascii(type),
                 (unsigned long long)blk_rq_pos(req) << 9, blk_rq_bytes(req));
         result = sock_xmit(nbd, 1, &request, sizeof(request),
-                        (nbd_cmd(req) == NBD_CMD_WRITE) ? MSG_MORE : 0);
+                        (type == NBD_CMD_WRITE) ? MSG_MORE : 0);
         if (result <= 0) {
                 dev_err(disk_to_dev(nbd->disk),
                         "Send control failed (result %d)\n", result);
                 return -EIO;
         }
 
-        if (nbd_cmd(req) == NBD_CMD_WRITE) {
+        if (type == NBD_CMD_WRITE) {
                 struct req_iterator iter;
                 struct bio_vec bvec;
                 /*
@@ -352,7 +363,7 @@ static struct request *nbd_read_stat(struct nbd_device *nbd)
         }
 
         dev_dbg(nbd_to_dev(nbd), "request %p: got reply\n", req);
-        if (nbd_cmd(req) == NBD_CMD_READ) {
+        if (rq_data_dir(req) != WRITE) {
                 struct req_iterator iter;
                 struct bio_vec bvec;
 
@@ -452,23 +463,11 @@ static void nbd_handle_req(struct nbd_device *nbd, struct request *req)
         if (req->cmd_type != REQ_TYPE_FS)
                 goto error_out;
 
-        nbd_cmd(req) = NBD_CMD_READ;
-        if (rq_data_dir(req) == WRITE) {
-                if ((req->cmd_flags & REQ_DISCARD)) {
-                        WARN_ON(!(nbd->flags & NBD_FLAG_SEND_TRIM));
-                        nbd_cmd(req) = NBD_CMD_TRIM;
-                } else
-                        nbd_cmd(req) = NBD_CMD_WRITE;
-                if (nbd->flags & NBD_FLAG_READ_ONLY) {
-                        dev_err(disk_to_dev(nbd->disk),
-                                "Write on read-only\n");
-                        goto error_out;
-                }
-        }
-
-        if (req->cmd_flags & REQ_FLUSH) {
-                BUG_ON(unlikely(blk_rq_sectors(req)));
-                nbd_cmd(req) = NBD_CMD_FLUSH;
+        if (rq_data_dir(req) == WRITE &&
+            (nbd->flags & NBD_FLAG_READ_ONLY)) {
+                dev_err(disk_to_dev(nbd->disk),
+                        "Write on read-only\n");
+                goto error_out;
         }
 
         req->errors = 0;
@@ -592,8 +591,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
                 fsync_bdev(bdev);
                 mutex_lock(&nbd->tx_lock);
                 blk_rq_init(NULL, &sreq);
-                sreq.cmd_type = REQ_TYPE_SPECIAL;
-                nbd_cmd(&sreq) = NBD_CMD_DISC;
+                sreq.cmd_type = REQ_TYPE_DRV_PRIV;
 
                 /* Check again after getting mutex back.  */
                 if (!nbd->sock)