From patchwork Mon Jun 13 18:16:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 581559 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B90FC43334 for ; Mon, 13 Jun 2022 20:06:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349981AbiFMUGi (ORCPT ); Mon, 13 Jun 2022 16:06:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347537AbiFMUGH (ORCPT ); Mon, 13 Jun 2022 16:06:07 -0400 Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 776EABDA1A; Mon, 13 Jun 2022 11:41:04 -0700 (PDT) Received: from localhost (127.0.0.1) (HELO v370.home.net.pl) by /usr/run/smtp (/usr/run/postfix/private/idea_relay_lmtp) via UNIX with SMTP (IdeaSmtpServer 5.0.0) id 98948afc32f47701; Mon, 13 Jun 2022 20:41:02 +0200 Received: from kreacher.localnet (unknown [213.134.187.64]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by v370.home.net.pl (Postfix) with ESMTPSA id 18F9866C81D; Mon, 13 Jun 2022 20:41:02 +0200 (CEST) From: "Rafael J. Wysocki" To: Linux ACPI Cc: LKML , Linux PM , Andy Shevchenko , Mika Westerberg , Hans de Goede , Sakari Ailus Subject: [PATCH v2 07/16] ACPI: property: Use acpi_dev_for_each_child() for child lookup Date: Mon, 13 Jun 2022 20:16:30 +0200 Message-ID: <1916226.PYKUYFuaPT@kreacher> In-Reply-To: <2653857.mvXUDI8C0e@kreacher> References: <1843211.tdWV9SEqCh@kreacher> <2653857.mvXUDI8C0e@kreacher> MIME-Version: 1.0 X-CLIENT-IP: 213.134.187.64 X-CLIENT-HOSTNAME: 213.134.187.64 X-VADE-SPAMSTATE: clean X-VADE-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgedvfedruddujedguddviecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfjqffogffrnfdpggftiffpkfenuceurghilhhouhhtmecuudehtdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephffvvefufffkjghfggfgtgesthfuredttddtjeenucfhrhhomhepfdftrghfrggvlhculfdrucghhihsohgtkhhifdcuoehrjhifsehrjhifhihsohgtkhhirdhnvghtqeenucggtffrrghtthgvrhhnpedvffeuiedtgfdvtddugeeujedtffetteegfeekffdvfedttddtuefhgeefvdejhfenucfkphepvddufedrudefgedrudekjedrieegnecuvehluhhsthgvrhfuihiivgepvdenucfrrghrrghmpehinhgvthepvddufedrudefgedrudekjedrieegpdhhvghlohepkhhrvggrtghhvghrrdhlohgtrghlnhgvthdpmhgrihhlfhhrohhmpedftfgrfhgrvghlucflrdcuhgihshhotghkihdfuceorhhjfiesrhhjfiihshhotghkihdrnhgvtheqpdhnsggprhgtphhtthhopeejpdhrtghpthhtoheplhhinhhugidqrggtphhisehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqkhgvrhhnvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqphhmsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheprghnughrihihrdhshhgvvhgthhgvnhhkoheslhhinhhugidrihhn thgvlhdrtghomhdprhgtphhtthhopehmihhkrgdrfigvshhtvghrsggvrhhgsehlihhnuhigrdhinhhtvghlrdgtohhmpdhrtghpthhtohephhguvghgohgvuggvsehrvgguhhgrthdrtghomhdprhgtphhtthhopehsrghkrghrihdrrghilhhusheslhhinhhugidrihhnthgvlhdrtghomh X-DCC--Metrics: v370.home.net.pl 1024; Body=7 Fuz1=7 Fuz2=7 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Rafael J. Wysocki Instead of using the list of children of an ACPI device directly, use acpi_dev_for_each_child() to find the next child of a given ACPI device. This will help to eliminate the children list head from struct acpi_device as it is redundant and it is used in questionable ways in some places (in particular, locking is needed for walking the list pointed to it safely, but it is often missing). Signed-off-by: Rafael J. Wysocki Reviewed-by: Andy Shevchenko --- v1 -> v2: * Add R-by from Andy. --- drivers/acpi/property.c | 47 +++++++++++++++++++++++++---------------------- 1 file changed, 25 insertions(+), 22 deletions(-) Index: linux-pm/drivers/acpi/property.c =================================================================== --- linux-pm.orig/drivers/acpi/property.c +++ linux-pm/drivers/acpi/property.c @@ -1012,6 +1012,22 @@ static int acpi_node_prop_read(const str propname, proptype, val, nval); } +static int stop_on_next(struct acpi_device *adev, void *data) +{ + struct acpi_device **ret_p = data; + + if (!*ret_p) { + *ret_p = adev; + return 1; + } + + /* Skip until the "previous" object is found. */ + if (*ret_p == adev) + *ret_p = NULL; + + return 0; +} + /** * acpi_get_next_subnode - Return the next child node handle for a fwnode * @fwnode: Firmware node to find the next child node for. @@ -1020,35 +1036,22 @@ static int acpi_node_prop_read(const str struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode, struct fwnode_handle *child) { - const struct acpi_device *adev = to_acpi_device_node(fwnode); - const struct list_head *head; - struct list_head *next; + struct acpi_device *adev = to_acpi_device_node(fwnode); if ((!child || is_acpi_device_node(child)) && adev) { - struct acpi_device *child_adev; + struct acpi_device *child_adev = to_acpi_device_node(child); + + acpi_dev_for_each_child(adev, stop_on_next, &child_adev); + if (child_adev) + return acpi_fwnode_handle(child_adev); - head = &adev->children; - if (list_empty(head)) - goto nondev; - - if (child) { - adev = to_acpi_device_node(child); - next = adev->node.next; - if (next == head) { - child = NULL; - goto nondev; - } - child_adev = list_entry(next, struct acpi_device, node); - } else { - child_adev = list_first_entry(head, struct acpi_device, - node); - } - return acpi_fwnode_handle(child_adev); + child = NULL; } - nondev: if (!child || is_acpi_data_node(child)) { const struct acpi_data_node *data = to_acpi_data_node(fwnode); + const struct list_head *head; + struct list_head *next; struct acpi_data_node *dn; /*