IB/core: Modify conditional on ucontext existence

Since we allow to call legacy verbs using their extended counterpart,
the check on ucontext has to move up to a common area in case this verb
is ever extended.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/uverbs_main.c

@@ -735,6 +735,12 @@ static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 		goto out;
 	}
 
+	if (!file->ucontext &&
+	    command != IB_USER_VERBS_CMD_GET_CONTEXT) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	flags = (hdr.command &
 		 IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
 
@@ -745,12 +751,6 @@ static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 			goto out;
 		}
 
-		if (!file->ucontext &&
-		    command != IB_USER_VERBS_CMD_GET_CONTEXT) {
-			ret = -EINVAL;
-			goto out;
-		}
-
 		if (hdr.in_words * 4 != count) {
 			ret = -EINVAL;
 			goto out;