svn commit: r300575 - head/sys/compat/linuxkpi/common/include/linux

[Hans Petter Selasky]

Author: hselasky
Date: Tue May 24 07:06:04 2016
New Revision: 300575
URL: https://svnweb.freebsd.org/changeset/base/300575

Log:
  Use make_dev_s() instead of make_dev() to avoid race setting
  "si_drv1". Convert panic() into regular error while at it.
  
  Suggested by:	jhb @
  MFC after:	1 week
  Sponsored by:	Mellanox Technologies

Modified:
  head/sys/compat/linuxkpi/common/include/linux/cdev.h

Modified: head/sys/compat/linuxkpi/common/include/linux/cdev.h
==============================================================================
--- head/sys/compat/linuxkpi/common/include/linux/cdev.h	Tue May 24 06:42:14 2016	(r300574)
+++ head/sys/compat/linuxkpi/common/include/linux/cdev.h	Tue May 24 07:06:04 2016	(r300575)
@@ -2,7 +2,7 @@
  * Copyright (c) 2010 Isilon Systems, Inc.
  * Copyright (c) 2010 iX Systems, Inc.
  * Copyright (c) 2010 Panasas, Inc.
- * Copyright (c) 2013, 2014 Mellanox Technologies, Ltd.
+ * Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -80,12 +80,27 @@ cdev_put(struct linux_cdev *p)
 static inline int
 cdev_add(struct linux_cdev *cdev, dev_t dev, unsigned count)
 {
+	struct make_dev_args args;
+	int error;
+
 	if (count != 1)
-		panic("cdev_add: Unsupported count: %d", count);
-	cdev->cdev = make_dev(&linuxcdevsw, MINOR(dev), 0, 0, 0700, 
-	    "%s", kobject_name(&cdev->kobj));
+		return (-EINVAL);
+
 	cdev->dev = dev;
-	cdev->cdev->si_drv1 = cdev;
+
+	/* Setup arguments for make_dev_s() */
+	make_dev_args_init(&args);
+	args.mda_devsw = &linuxcdevsw;
+	args.mda_uid = 0;
+	args.mda_gid = 0;
+	args.mda_mode = 0700;
+	args.mda_si_drv1 = cdev;
+	args.mda_unit = MINOR(dev);
+
+	error = make_dev_s(&args, &cdev->cdev, "%s",
+	    kobject_name(&cdev->kobj));
+	if (error)
+		return (-error);
 
 	kobject_get(cdev->kobj.parent);
 	return (0);
@@ -94,10 +109,24 @@ cdev_add(struct linux_cdev *cdev, dev_t 
 static inline int
 cdev_add_ext(struct linux_cdev *cdev, dev_t dev, uid_t uid, gid_t gid, int mode)
 {
-	cdev->cdev = make_dev(&linuxcdevsw, MINOR(dev), uid, gid, mode, 
-	    "%s/%d", kobject_name(&cdev->kobj), MINOR(dev));
+	struct make_dev_args args;
+	int error;
+
 	cdev->dev = dev;
-	cdev->cdev->si_drv1 = cdev;
+	
+	/* Setup arguments for make_dev_s() */
+	make_dev_args_init(&args);
+	args.mda_devsw = &linuxcdevsw;
+	args.mda_uid = uid;
+	args.mda_gid = gid;
+	args.mda_mode = mode;
+	args.mda_si_drv1 = cdev;
+	args.mda_unit = MINOR(dev);
+
+	error = make_dev_s(&args, &cdev->cdev, "%s/%d",
+	    kobject_name(&cdev->kobj), MINOR(dev));
+	if (error)
+		return (-error);
 
 	kobject_get(cdev->kobj.parent);
 	return (0);