From nobody Thu Oct 9 13:21:37 2025 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 752792877E7 for ; Wed, 18 Jun 2025 10:09:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750241363; cv=none; b=RX2HStw5T9GkB5gygnW+bXwXCaT2ODvfbsC+NG/wvBA25wcTLXEyFBzuKnQ57gs3yHqTaQuKTd6Z+LoLt3lZ4h6CWn6KAEdxHjmPPRvJ1JMe5Ade3yLazzUqdyDhgAzX9DoUIyitV+bhT7rp2gg1gVFvH7mJNLFvD5Yba0LiUXQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750241363; c=relaxed/simple; bh=xpn/EHIABiAzTJLgy/jCZXbyjPag492xA6bZdLVSFwI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=g0dL9LrGRbFcgT5FCHlro54Rp/0udteC6TJ3F8U9SSl2dGkUtU0p9p3KsuunIrFSprV0ty5xGT6EFtzHIykkWXWJffB+Vuuzz72ulQLylMFtIeqBqu5jKIaLtV8XmNCFXeRYncoIfahIgFZeAVBATyJ7M+cDRmirr7gSUqAMDcM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=QewFDs4v; arc=none smtp.client-ip=198.175.65.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="QewFDs4v" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1750241362; x=1781777362; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=xpn/EHIABiAzTJLgy/jCZXbyjPag492xA6bZdLVSFwI=; b=QewFDs4vcdiXg4YwOfOdxrLP8WeXB/yXsoqqRCD666eK+yZ6ko8oIVWL kpkmLyIVe/TCRmhkMmv1WSgkSGANZOHA2tN6rdEs0Vy1wCbv7OlVL8ruD 6Chz7pJbBbEasR9tYG7veSihuzy0tx8oEoPstOiMRN38ZpvZKkWXY7dLM /r7mxJTDsBUXPOq+dKt7rb/23QJHgB4YpAr6qLdwWKoTBsoyMPz2voble 4VsSpOdCrHRbYogYTOAMDFAkcIMx5aof7I4Zz+A8CJDhSNsBAzrE4Rq1p glDik6tvf35eAkL6VVOD6e7sxW4W5+ugWSKu6m34pQhb6LR8AQbgB6j3g w==; X-CSE-ConnectionGUID: PGIVtt8+TzKcbJGFYkK0TA== X-CSE-MsgGUID: BGlCwLKITDizssDjo1BRaA== X-IronPort-AV: E=McAfee;i="6800,10657,11467"; a="52591024" X-IronPort-AV: E=Sophos;i="6.16,245,1744095600"; d="scan'208";a="52591024" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa110.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jun 2025 03:08:12 -0700 X-CSE-ConnectionGUID: dxAJV6kYS1CuINge0wA7hQ== X-CSE-MsgGUID: zrRYSo7sShikWKGAWN8j3A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.16,245,1744095600"; d="scan'208";a="149461269" Received: from sannilnx-dsk.jer.intel.com ([10.12.231.107]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jun 2025 03:08:10 -0700 From: Alexander Usyskin To: Greg Kroah-Hartman Cc: Reuven Abliyev , Alexander Usyskin , linux-kernel@vger.kernel.org Subject: [char-misc-next 3/3] mei: make char device control its own lifetime Date: Wed, 18 Jun 2025 12:54:33 +0300 Message-ID: <20250618095433.3943546-4-alexander.usyskin@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250618095433.3943546-1-alexander.usyskin@intel.com> References: <20250618095433.3943546-1-alexander.usyskin@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Allocate character device dynamically and allow to control its own lifetime as it may outlive mei_device structure while character device closes after parent device is removed from the system. Signed-off-by: Alexander Usyskin --- drivers/misc/mei/main.c | 34 +++++++++++++++++++++------------- drivers/misc/mei/mei_dev.h | 4 ++-- 2 files changed, 23 insertions(+), 15 deletions(-) diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c index c160703d0782..2162a8de9e6a 100644 --- a/drivers/misc/mei/main.c +++ b/drivers/misc/mei/main.c @@ -51,7 +51,7 @@ static int mei_open(struct inode *inode, struct file *fil= e) =20 int err; =20 - dev =3D mei_device_get(container_of(inode->i_cdev, struct mei_device, cde= v)); + dev =3D mei_device_get(idr_find(&mei_idr, iminor(inode))); if (!dev) return -ENODEV; =20 @@ -1122,7 +1122,10 @@ void mei_set_devstate(struct mei_device *dev, enum m= ei_dev_state state) =20 dev->dev_state =3D state; =20 - clsdev =3D class_find_device_by_devt(&mei_class, dev->cdev.dev); + if (!dev->cdev) + return; + + clsdev =3D class_find_device_by_devt(&mei_class, dev->cdev->dev); if (clsdev) { sysfs_notify(&clsdev->kobj, NULL, "dev_state"); put_device(clsdev); @@ -1227,16 +1230,21 @@ int mei_register(struct mei_device *dev, struct dev= ice *parent) =20 /* Fill in the data structures */ devno =3D MKDEV(MAJOR(mei_devt), dev->minor); - cdev_init(&dev->cdev, &mei_fops); - dev->cdev.owner =3D parent->driver->owner; - cdev_set_parent(&dev->cdev, &parent->kobj); + dev->cdev =3D cdev_alloc(); + if (!dev->cdev) { + ret =3D -ENOMEM; + goto err; + } + dev->cdev->ops =3D &mei_fops; + dev->cdev->owner =3D parent->driver->owner; + cdev_set_parent(dev->cdev, &parent->kobj); =20 /* Add the device */ - ret =3D cdev_add(&dev->cdev, devno, 1); + ret =3D cdev_add(dev->cdev, devno, 1); if (ret) { dev_err(parent, "unable to add device %d:%d\n", MAJOR(mei_devt), dev->minor); - goto err_dev_add; + goto err_del_cdev; } =20 clsdev =3D device_create_with_groups(&mei_class, parent, devno, @@ -1247,16 +1255,16 @@ int mei_register(struct mei_device *dev, struct dev= ice *parent) dev_err(parent, "unable to create device %d:%d\n", MAJOR(mei_devt), dev->minor); ret =3D PTR_ERR(clsdev); - goto err_dev_create; + goto err_del_cdev; } =20 mei_dbgfs_register(dev, dev_name(clsdev)); =20 return 0; =20 -err_dev_create: - cdev_del(&dev->cdev); -err_dev_add: +err_del_cdev: + cdev_del(dev->cdev); +err: mei_minor_free(dev); return ret; } @@ -1266,8 +1274,8 @@ void mei_deregister(struct mei_device *dev) { int devno; =20 - devno =3D dev->cdev.dev; - cdev_del(&dev->cdev); + devno =3D dev->cdev->dev; + cdev_del(dev->cdev); =20 mei_dbgfs_deregister(dev); =20 diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h index b745cde80662..8f081c6735c4 100644 --- a/drivers/misc/mei/mei_dev.h +++ b/drivers/misc/mei/mei_dev.h @@ -471,7 +471,7 @@ struct mei_dev_timeouts { * struct mei_device - MEI private device struct * * @dev : device on a bus - * @cdev : character device + * @cdev : character device pointer * @minor : minor number allocated for device * * @refcnt : struct reference count @@ -559,7 +559,7 @@ struct mei_dev_timeouts { */ struct mei_device { struct device *dev; - struct cdev cdev; + struct cdev *cdev; int minor; =20 struct kref refcnt; --=20 2.43.0