From 506aafbad34297bdd8727e310f8ae830715159f4 Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Mon, 20 Feb 2023 12:14:19 +0100 Subject: [PATCH] media: v4l: async: Clean up testing for duplicate async subdevs MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit There's a need to verify that a single async sub-device isn't being added multiple times, this would be an error. This takes place at the time of adding the async sub-device to the notifier's list as well as when the notifier is added to the global notifier's list. Use the pointer to the sub-device for testing this instead of an index to an array that is long gone. (There was an array of async sub-devices in the notifier before it was converted to a linked list by commit 66beb323e4a0 ("media: v4l2: async: Remove notifier subdevs array").) Signed-off-by: Sakari Ailus Tested-by: Philipp Zabel # imx6qp Tested-by: Niklas Söderlund # rcar + adv746x Tested-by: Aishwarya Kothari # Apalis i.MX6Q with TC358743 Tested-by: Lad Prabhakar # Renesas RZ/G2L SMARC Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-async.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c index c578112..9b79bcc 100644 --- a/drivers/media/v4l2-core/v4l2-async.c +++ b/drivers/media/v4l2-core/v4l2-async.c @@ -519,23 +519,23 @@ __v4l2_async_nf_has_async_subdev(struct v4l2_async_notifier *notifier, } /* - * Find out whether an async sub-device was set up already or - * whether it exists in a given notifier before @this_index. - * If @this_index < 0, search the notifier's entire @asd_list. + * Find out whether an async sub-device was set up already or whether it exists + * in a given notifier. The skip_self argument is used to skip testing the same + * sub-device in the notifier in case the sub-device has been already added to + * the notifier. */ static bool v4l2_async_nf_has_async_subdev(struct v4l2_async_notifier *notifier, - struct v4l2_async_subdev *asd, int this_index) + struct v4l2_async_subdev *asd, bool skip_self) { struct v4l2_async_subdev *asd_y; - int j = 0; lockdep_assert_held(&list_lock); /* Check that an asd is not being added more than once. */ list_for_each_entry(asd_y, ¬ifier->asd_list, asd_list) { - if (this_index >= 0 && j++ >= this_index) - break; + if (skip_self && asd == asd_y) + continue; if (asd_equal(asd, asd_y)) return true; } @@ -550,7 +550,7 @@ v4l2_async_nf_has_async_subdev(struct v4l2_async_notifier *notifier, static int v4l2_async_nf_asd_valid(struct v4l2_async_notifier *notifier, struct v4l2_async_subdev *asd, - int this_index) + bool skip_self) { struct device *dev = notifier_dev(notifier); @@ -560,7 +560,7 @@ static int v4l2_async_nf_asd_valid(struct v4l2_async_notifier *notifier, switch (asd->match_type) { case V4L2_ASYNC_MATCH_I2C: case V4L2_ASYNC_MATCH_FWNODE: - if (v4l2_async_nf_has_async_subdev(notifier, asd, this_index)) { + if (v4l2_async_nf_has_async_subdev(notifier, asd, skip_self)) { dev_dbg(dev, "v4l2-async: subdev descriptor already listed in a notifier\n"); return -EEXIST; } @@ -583,7 +583,7 @@ EXPORT_SYMBOL(v4l2_async_nf_init); static int __v4l2_async_nf_register(struct v4l2_async_notifier *notifier) { struct v4l2_async_subdev *asd; - int ret, i = 0; + int ret; INIT_LIST_HEAD(¬ifier->waiting); INIT_LIST_HEAD(¬ifier->done); @@ -591,7 +591,7 @@ static int __v4l2_async_nf_register(struct v4l2_async_notifier *notifier) mutex_lock(&list_lock); list_for_each_entry(asd, ¬ifier->asd_list, asd_list) { - ret = v4l2_async_nf_asd_valid(notifier, asd, i++); + ret = v4l2_async_nf_asd_valid(notifier, asd, true); if (ret) goto err_unlock; @@ -725,7 +725,7 @@ static int __v4l2_async_nf_add_subdev(struct v4l2_async_notifier *notifier, mutex_lock(&list_lock); - ret = v4l2_async_nf_asd_valid(notifier, asd, -1); + ret = v4l2_async_nf_asd_valid(notifier, asd, false); if (ret) goto unlock; -- 2.7.4