From patchwork Fri May 8 14:13:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Ardelean X-Patchwork-Id: 11536701 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0F51F14C0 for ; Fri, 8 May 2020 14:13:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EAFB124958 for ; Fri, 8 May 2020 14:13:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726767AbgEHONL (ORCPT ); Fri, 8 May 2020 10:13:11 -0400 Received: from mx0a-00128a01.pphosted.com ([148.163.135.77]:23038 "EHLO mx0a-00128a01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726904AbgEHONL (ORCPT ); Fri, 8 May 2020 10:13:11 -0400 Received: from pps.filterd (m0167088.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 048E52xY006944; Fri, 8 May 2020 10:13:09 -0400 Received: from nwd2mta4.analog.com ([137.71.173.58]) by mx0a-00128a01.pphosted.com with ESMTP id 30vtef2mad-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 08 May 2020 10:13:09 -0400 Received: from ASHBMBX8.ad.analog.com (ashbmbx8.ad.analog.com [10.64.17.5]) by nwd2mta4.analog.com (8.14.7/8.14.7) with ESMTP id 048ED8Ad046078 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=FAIL); Fri, 8 May 2020 10:13:08 -0400 Received: from ASHBCASHYB4.ad.analog.com (10.64.17.132) by ASHBMBX8.ad.analog.com (10.64.17.5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1779.2; Fri, 8 May 2020 10:13:07 -0400 Received: from ASHBMBX9.ad.analog.com (10.64.17.10) by ASHBCASHYB4.ad.analog.com (10.64.17.132) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1779.2; Fri, 8 May 2020 10:13:07 -0400 Received: from zeus.spd.analog.com (10.64.82.11) by ASHBMBX9.ad.analog.com (10.64.17.10) with Microsoft SMTP Server id 15.1.1779.2 via Frontend Transport; Fri, 8 May 2020 10:13:07 -0400 Received: from localhost.localdomain ([10.48.65.12]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 048ED5JY031800; Fri, 8 May 2020 10:13:05 -0400 From: Alexandru Ardelean To: , CC: , Alexandru Ardelean Subject: [PATCH 1/3] iio: core: wrap IIO device into a iio_dev_priv object Date: Fri, 8 May 2020 17:13:04 +0300 Message-ID: <20200508141306.17222-1-alexandru.ardelean@analog.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-ADIRoutedOnPrem: True X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216,18.0.676 definitions=2020-05-08_13:2020-05-08,2020-05-08 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 priorityscore=1501 malwarescore=0 lowpriorityscore=0 suspectscore=2 clxscore=1015 phishscore=0 mlxlogscore=999 adultscore=0 mlxscore=0 bulkscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2005080126 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org There are plenty of bad designs we want to discourage or not have to review manually usually about accessing private (marked as [INTERN]) fields of 'struct iio_dev'. This is difficult, as a lot of users copy drivers, and not always the best examples. A better idea is to hide those fields into the framework. For 'struct iio_dev' this is a 'struct iio_dev_priv' which wraps a public 'struct iio_dev' object. In the next patches, some fields will be moved to this new struct, each with it's own rework. This rework will not be complete[-able] for a while, as many fields need some drivers to be reworked in order to finalize them (e.g. 'indio_dev->mlock'). But some fields can already be moved, and in time, all of them may get there (in the 'struct iio_dev_priv' object). We also need to hide the implementations for 'iio_priv()' & 'iio_priv_to_dev()', as the pointer arithmetic will not match once things are moved. Signed-off-by: Alexandru Ardelean --- Just as a note here, I've been running this patchset without a problem for 2 weeks now in a work branch. But it's only been a setup, so no idea if some other thing may cause bigger issues. This small patchset is meant to kickstart this, for GSoC people or for people wanting to start contributing to IIO. drivers/iio/iio_core.h | 11 +++++++++++ drivers/iio/industrialio-core.c | 32 +++++++++++++++++++++++++++----- include/linux/iio/iio.h | 12 ++---------- 3 files changed, 40 insertions(+), 15 deletions(-) diff --git a/drivers/iio/iio_core.h b/drivers/iio/iio_core.h index fd9a5f1d5e51..84f3b4590c05 100644 --- a/drivers/iio/iio_core.h +++ b/drivers/iio/iio_core.h @@ -17,6 +17,17 @@ struct iio_dev; extern struct device_type iio_device_type; +/** + * struct iio_dev_priv - industrial I/O device private information + * @indio_dev: public IIO device object + */ +struct iio_dev_priv { + struct iio_dev indio_dev; +}; + +#define to_iio_dev_priv(indio_dev) \ + container_of(indio_dev, struct iio_dev_priv, indio_dev) + int __iio_add_chan_devattr(const char *postfix, struct iio_chan_spec const *chan, ssize_t (*func)(struct device *dev, diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 462d3e810013..f0888dd84d3d 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -164,6 +164,23 @@ static const char * const iio_chan_info_postfix[] = { [IIO_CHAN_INFO_THERMOCOUPLE_TYPE] = "thermocouple_type", }; + +void *iio_priv(const struct iio_dev *indio_dev) +{ + struct iio_dev_priv *iio_dev_priv = to_iio_dev_priv(indio_dev); + return (char *)iio_dev_priv + ALIGN(sizeof(struct iio_dev_priv), IIO_ALIGN); +} +EXPORT_SYMBOL_GPL(iio_priv); + +struct iio_dev *iio_priv_to_dev(void *priv) +{ + struct iio_dev_priv *iio_dev_priv = + (struct iio_dev_priv *)((char *)priv - + ALIGN(sizeof(struct iio_dev_priv), IIO_ALIGN)); + return &iio_dev_priv->indio_dev; +} +EXPORT_SYMBOL_GPL(iio_priv_to_dev); + /** * iio_find_channel_from_si() - get channel from its scan index * @indio_dev: device @@ -1476,6 +1493,8 @@ static void iio_device_unregister_sysfs(struct iio_dev *indio_dev) static void iio_dev_release(struct device *device) { struct iio_dev *indio_dev = dev_to_iio_dev(device); + struct iio_dev_priv *iio_dev_priv = to_iio_dev_priv(indio_dev); + if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES) iio_device_unregister_trigger_consumer(indio_dev); iio_device_unregister_eventset(indio_dev); @@ -1484,7 +1503,7 @@ static void iio_dev_release(struct device *device) iio_buffer_put(indio_dev->buffer); ida_simple_remove(&iio_ida, indio_dev->id); - kfree(indio_dev); + kfree(iio_dev_priv); } struct device_type iio_device_type = { @@ -1498,10 +1517,11 @@ struct device_type iio_device_type = { **/ struct iio_dev *iio_device_alloc(int sizeof_priv) { + struct iio_dev_priv *iio_dev_priv; struct iio_dev *dev; size_t alloc_size; - alloc_size = sizeof(struct iio_dev); + alloc_size = sizeof(struct iio_dev_priv); if (sizeof_priv) { alloc_size = ALIGN(alloc_size, IIO_ALIGN); alloc_size += sizeof_priv; @@ -1509,10 +1529,12 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) /* ensure 32-byte alignment of whole construct ? */ alloc_size += IIO_ALIGN - 1; - dev = kzalloc(alloc_size, GFP_KERNEL); - if (!dev) + iio_dev_priv = kzalloc(alloc_size, GFP_KERNEL); + if (!iio_dev_priv) return NULL; + dev = &iio_dev_priv->indio_dev; + dev->dev.groups = dev->groups; dev->dev.type = &iio_device_type; dev->dev.bus = &iio_bus_type; @@ -1526,7 +1548,7 @@ struct iio_dev *iio_device_alloc(int sizeof_priv) if (dev->id < 0) { /* cannot use a dev_err as the name isn't available */ pr_err("failed to get device id\n"); - kfree(dev); + kfree(iio_dev_priv); return NULL; } dev_set_name(&dev->dev, "iio:device%d", dev->id); diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index 5f9f439a4f01..38c4ea505394 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -678,16 +678,8 @@ static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev) #define IIO_ALIGN L1_CACHE_BYTES struct iio_dev *iio_device_alloc(int sizeof_priv); -static inline void *iio_priv(const struct iio_dev *indio_dev) -{ - return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN); -} - -static inline struct iio_dev *iio_priv_to_dev(void *priv) -{ - return (struct iio_dev *)((char *)priv - - ALIGN(sizeof(struct iio_dev), IIO_ALIGN)); -} +void *iio_priv(const struct iio_dev *indio_dev); +struct iio_dev *iio_priv_to_dev(void *priv); void iio_device_free(struct iio_dev *indio_dev); struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);