From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from nblzone-211-213.nblnetworks.fi ([83.145.211.213]:40292 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751393AbdJDVu7 (ORCPT ); Wed, 4 Oct 2017 17:50:59 -0400 From: Sakari Ailus To: linux-media@vger.kernel.org Cc: niklas.soderlund@ragnatech.se, maxime.ripard@free-electrons.com, hverkuil@xs4all.nl, laurent.pinchart@ideasonboard.com, pavel@ucw.cz, sre@kernel.org Subject: [PATCH v15 19/32] v4l: async: Ensure only unique fwnodes are registered to notifiers Date: Thu, 5 Oct 2017 00:50:38 +0300 Message-Id: <20171004215051.13385-20-sakari.ailus@linux.intel.com> In-Reply-To: <20171004215051.13385-1-sakari.ailus@linux.intel.com> References: <20171004215051.13385-1-sakari.ailus@linux.intel.com> Sender: linux-media-owner@vger.kernel.org List-ID: While registering a notifier, check that each newly added fwnode is unique, and return an error if it is not. Also check that a newly added notifier does not have the same fwnodes twice. Signed-off-by: Sakari Ailus Acked-by: Hans Verkuil --- drivers/media/v4l2-core/v4l2-async.c | 82 +++++++++++++++++++++++++++++++++--- 1 file changed, 77 insertions(+), 5 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c index 3621ed6e6e3c..e1fe3567127a 100644 --- a/drivers/media/v4l2-core/v4l2-async.c +++ b/drivers/media/v4l2-core/v4l2-async.c @@ -330,8 +330,71 @@ static void v4l2_async_notifier_unbind_all_subdevs( notifier->parent = NULL; } +/* See if an fwnode can be found in a notifier's lists. */ +static bool __v4l2_async_notifier_fwnode_has_async_subdev( + struct v4l2_async_notifier *notifier, struct fwnode_handle *fwnode) +{ + struct v4l2_async_subdev *asd; + struct v4l2_subdev *sd; + + list_for_each_entry(asd, ¬ifier->waiting, list) { + if (asd->match_type != V4L2_ASYNC_MATCH_FWNODE) + continue; + + if (asd->match.fwnode.fwnode == fwnode) + return true; + } + + list_for_each_entry(sd, ¬ifier->done, async_list) { + if (WARN_ON(!sd->asd)) + continue; + + if (sd->asd->match_type != V4L2_ASYNC_MATCH_FWNODE) + continue; + + if (sd->asd->match.fwnode.fwnode == fwnode) + return true; + } + + return false; +} + +/* + * Find out whether an async sub-device was set up for an fwnode already or + * whether it exists in a given notifier before @this_index. + */ +static bool v4l2_async_notifier_fwnode_has_async_subdev( + struct v4l2_async_notifier *notifier, struct fwnode_handle *fwnode, + unsigned int this_index) +{ + unsigned int j; + + lockdep_assert_held(&list_lock); + + /* Check that an fwnode is not being added more than once. */ + for (j = 0; j < this_index; j++) { + struct v4l2_async_subdev *asd = notifier->subdevs[this_index]; + struct v4l2_async_subdev *other_asd = notifier->subdevs[j]; + + if (other_asd->match_type == V4L2_ASYNC_MATCH_FWNODE && + asd->match.fwnode.fwnode == + other_asd->match.fwnode.fwnode) + return true; + } + + /* Check than an fwnode did not exist in other notifiers. */ + list_for_each_entry(notifier, ¬ifier_list, list) + if (__v4l2_async_notifier_fwnode_has_async_subdev( + notifier, fwnode)) + return true; + + return false; +} + static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier) { + struct device *dev = + notifier->v4l2_dev ? notifier->v4l2_dev->dev : NULL; struct v4l2_async_subdev *asd; int ret; int i; @@ -342,6 +405,8 @@ static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier) INIT_LIST_HEAD(¬ifier->waiting); INIT_LIST_HEAD(¬ifier->done); + mutex_lock(&list_lock); + for (i = 0; i < notifier->num_subdevs; i++) { asd = notifier->subdevs[i]; @@ -349,19 +414,25 @@ static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier) case V4L2_ASYNC_MATCH_CUSTOM: case V4L2_ASYNC_MATCH_DEVNAME: case V4L2_ASYNC_MATCH_I2C: + break; case V4L2_ASYNC_MATCH_FWNODE: + if (v4l2_async_notifier_fwnode_has_async_subdev( + notifier, asd->match.fwnode.fwnode, i)) { + dev_err(dev, + "fwnode has already been registered or in notifier's subdev list\n"); + ret = -EEXIST; + goto out_unlock; + } break; default: - dev_err(notifier->v4l2_dev ? notifier->v4l2_dev->dev : NULL, - "Invalid match type %u on %p\n", + dev_err(dev, "Invalid match type %u on %p\n", asd->match_type, asd); - return -EINVAL; + ret = -EINVAL; + goto out_unlock; } list_add_tail(&asd->list, ¬ifier->waiting); } - mutex_lock(&list_lock); - ret = v4l2_async_notifier_try_all_subdevs(notifier); if (ret) goto err_unbind; @@ -373,6 +444,7 @@ static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier) /* Keep also completed notifiers on the list */ list_add(¬ifier->list, ¬ifier_list); +out_unlock: mutex_unlock(&list_lock); return 0; -- 2.11.0