From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.20]) (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 8301C248F5E for ; Mon, 30 Jun 2025 09:33:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.20 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751275988; cv=none; b=p8h5wPqLNyWZ4pvJ8inEYOepAOnGNVjUO/AXe6n8/daj3qPI8sYqVNIT3HZS/nPLu2BvlOkk1w4CThjoXpUrd70nCtc8U9GGcj/4tSkEB/gV1o8CBoiftswupatGqThXIiTQ8V45gB9H6Z1/nyaWGYkSJGfezGyDlaLJJlA4O9o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751275988; c=relaxed/simple; bh=FIfEkbz8JdHJOviN1RQuQrM8W1xMWoKA43IuApPDbZw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NDq+VLc5oDsCD3/ueboHtV8y75TGPFEbBrZyyLBUS3LQLz4HLtRfFfzZwNufWvkaCLWRfmSQdehkXRhxu9scB3u23nLWI1nmnYRZUYpCfppJhRQ+Zbt+jjLXzNB+ImswNFbrW3lB0KfJx+seV4dJU2LrEKNPBgaVajll+eAqRqQ= 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=Wkx3CpU9; arc=none smtp.client-ip=198.175.65.20 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="Wkx3CpU9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1751275987; x=1782811987; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FIfEkbz8JdHJOviN1RQuQrM8W1xMWoKA43IuApPDbZw=; b=Wkx3CpU9HcjZaNFDF6e73ltUrHPl386L4ZtlTvZUzR0EdAeU47mdakBT FrcOdy9ZtMh+LUWBmdOl+0QQQb+/x9hI1oZjtduObnmpf3C+nzYqtm1MZ P7T8h7j2ZX00aJzbdrCgpIMThBW7fIjoGNYnypwdbmzqZ3EDAUd+y8de8 Lfrx0k6k1/2v1jHgZjxAy1FU2YBfSFAjQXXcdK/jiV7NFRchefbWDbopp ApxUv+Uky/YFTHLB0q4StHobNsrqbexZyhvHwFPjkfGn/3ewPt5Vfm2kA ukLWKEy3mj+O5m2rHwMteJ/q8byucp2cF0HQNmRCdTNv4/JGd+TtFG21H A==; X-CSE-ConnectionGUID: Lhtr0b78TiWmmzsgJc2LIQ== X-CSE-MsgGUID: 2SqzciRdSk2jd7b/1TVmxA== X-IronPort-AV: E=McAfee;i="6800,10657,11479"; a="53218593" X-IronPort-AV: E=Sophos;i="6.16,277,1744095600"; d="scan'208";a="53218593" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jun 2025 02:33:07 -0700 X-CSE-ConnectionGUID: Lf0p4y5bRVubwnspdk+InA== X-CSE-MsgGUID: HS1TOjSoS2i6DkoHe/oZKg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.16,277,1744095600"; d="scan'208";a="153039561" Received: from sannilnx-dsk.jer.intel.com ([10.12.231.107]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jun 2025 02:33:05 -0700 From: Alexander Usyskin To: Greg Kroah-Hartman Cc: Reuven Abliyev , Alexander Usyskin , linux-kernel@vger.kernel.org Subject: [char-misc-next v2 2/5] mei: make char device control its own lifetime Date: Mon, 30 Jun 2025 12:19:39 +0300 Message-ID: <20250630091942.2116676-3-alexander.usyskin@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250630091942.2116676-1-alexander.usyskin@intel.com> References: <20250630091942.2116676-1-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: 8bit 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 | 36 +++++++++++++++++++++++------------- drivers/misc/mei/mei_dev.h | 4 ++-- 2 files changed, 25 insertions(+), 15 deletions(-) diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c index 95d4c1d8e4e6..5335cf39d663 100644 --- a/drivers/misc/mei/main.c +++ b/drivers/misc/mei/main.c @@ -51,7 +51,9 @@ static int mei_open(struct inode *inode, struct file *file) int err; - dev = container_of(inode->i_cdev, struct mei_device, cdev); + dev = idr_find(&mei_idr, iminor(inode)); + if (!dev) + return -ENODEV; mutex_lock(&dev->device_lock); @@ -1118,7 +1120,10 @@ void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state) dev->dev_state = state; - clsdev = class_find_device_by_devt(&mei_class, dev->cdev.dev); + if (!dev->cdev) + return; + + clsdev = class_find_device_by_devt(&mei_class, dev->cdev->dev); if (clsdev) { sysfs_notify(&clsdev->kobj, NULL, "dev_state"); put_device(clsdev); @@ -1223,16 +1228,21 @@ int mei_register(struct mei_device *dev, struct device *parent) /* Fill in the data structures */ devno = MKDEV(MAJOR(mei_devt), dev->minor); - cdev_init(&dev->cdev, &mei_fops); - dev->cdev.owner = parent->driver->owner; - cdev_set_parent(&dev->cdev, &parent->kobj); + dev->cdev = cdev_alloc(); + if (!dev->cdev) { + ret = -ENOMEM; + goto err; + } + dev->cdev->ops = &mei_fops; + dev->cdev->owner = parent->driver->owner; + cdev_set_parent(dev->cdev, &parent->kobj); /* Add the device */ - ret = cdev_add(&dev->cdev, devno, 1); + ret = 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; } clsdev = device_create_with_groups(&mei_class, parent, devno, @@ -1243,16 +1253,16 @@ int mei_register(struct mei_device *dev, struct device *parent) dev_err(parent, "unable to create device %d:%d\n", MAJOR(mei_devt), dev->minor); ret = PTR_ERR(clsdev); - goto err_dev_create; + goto err_del_cdev; } mei_dbgfs_register(dev, dev_name(clsdev)); return 0; -err_dev_create: - cdev_del(&dev->cdev); -err_dev_add: +err_del_cdev: + cdev_del(dev->cdev); +err: mei_minor_free(dev); return ret; } @@ -1262,8 +1272,8 @@ void mei_deregister(struct mei_device *dev) { int devno; - devno = dev->cdev.dev; - cdev_del(&dev->cdev); + devno = dev->cdev->dev; + cdev_del(dev->cdev); mei_dbgfs_deregister(dev); diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h index 37d7fb15cad7..0cc943afa80a 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 * * @write_list : write pending list @@ -557,7 +557,7 @@ struct mei_dev_timeouts { */ struct mei_device { struct device *dev; - struct cdev cdev; + struct cdev *cdev; int minor; struct list_head write_list; -- 2.43.0