From mboxrd@z Thu Jan 1 00:00:00 1970 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 8A1F5C433F5 for ; Wed, 6 Apr 2022 15:41:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236259AbiDFPnl (ORCPT ); Wed, 6 Apr 2022 11:43:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59766 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236258AbiDFPnS (ORCPT ); Wed, 6 Apr 2022 11:43:18 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 186E34E6F74; Wed, 6 Apr 2022 06:11:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1649250681; x=1680786681; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=xrVO3PD15uLGC0xOV5+sEkLrkVM/AfGYyeEPTlYt8Po=; b=ZhlbYAiyr4LRl54UxngjZEx8/nKQKs2w8QrjL26baI0/32kOR5qri8Lb K/zrERCQjTucs48sZqavlgVzx6IkIbMZsHX39dP3n3HOcrxM2mfWRBC/F FX9irX4MRSxHuckcDWgSZ7SpyLcmpt/mwlCLZ/il6pEmdi+U+QlLqQ5WH xeIqDY+uqwoG7F2+qkuj0ka/S8AMQXg/5yCJs8Q7uPwyR2nOI0AGYayXF pYKhhhA0x4PDWCFHXlRU0C8yO5K+ui4QTY77QH0lf9qAR4HYoXUeZRdST 2vzYnh99AfkqQ5VqWsDUf5YioeaaPVzOmcKQhbDSQrO5CibciPDZlDjCP Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10308"; a="261032517" X-IronPort-AV: E=Sophos;i="5.90,239,1643702400"; d="scan'208";a="261032517" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Apr 2022 06:09:57 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,239,1643702400"; d="scan'208";a="642045293" Received: from black.fi.intel.com ([10.237.72.28]) by FMSMGA003.fm.intel.com with ESMTP; 06 Apr 2022 06:09:54 -0700 Received: by black.fi.intel.com (Postfix, from userid 1003) id 626B216D; Wed, 6 Apr 2022 16:05:55 +0300 (EEST) From: Andy Shevchenko To: Andy Shevchenko , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Daniel Scally , Heikki Krogerus , Sakari Ailus , Greg Kroah-Hartman , "Rafael J. Wysocki" , Len Brown , Michael Walle , =?UTF-8?q?Nuno=20S=C3=A1?= Subject: [PATCH v5 1/4] device property: Allow error pointer to be passed to fwnode APIs Date: Wed, 6 Apr 2022 16:05:49 +0300 Message-Id: <20220406130552.30930-1-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org Some of the fwnode APIs might return an error pointer instead of NULL or valid fwnode handle. The result of such API call may be considered optional and hence the test for it is usually done in a form of fwnode = fwnode_find_reference(...); if (IS_ERR(fwnode)) ...error handling... Nevertheless the resulting fwnode may have bumped the reference count and hence caller of the above API is obliged to call fwnode_handle_put(). Since fwnode may be not valid either as NULL or error pointer the check has to be performed there. This approach uglifies the code and adds a point of making a mistake, i.e. forgetting about error point case. To prevent this, allow an error pointer to be passed to the fwnode APIs. Fixes: 83b34afb6b79 ("device property: Introduce fwnode_find_reference()") Reported-by: Nuno Sá Tested-by: Nuno Sá Acked-by: Nuno Sá Reviewed-by: Sakari Ailus Reviewed-by: Heikki Krogerus Signed-off-by: Andy Shevchenko --- v5: fixed return value in _get_reference_args() for secondary check (Michael) drivers/base/property.c | 89 +++++++++++++++++++++++------------------ include/linux/fwnode.h | 10 ++--- 2 files changed, 56 insertions(+), 43 deletions(-) diff --git a/drivers/base/property.c b/drivers/base/property.c index c0e94cce9c29..3376d3971a93 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -47,12 +47,14 @@ bool fwnode_property_present(const struct fwnode_handle *fwnode, { bool ret; + if (IS_ERR_OR_NULL(fwnode)) + return false; + ret = fwnode_call_bool_op(fwnode, property_present, propname); - if (ret == false && !IS_ERR_OR_NULL(fwnode) && - !IS_ERR_OR_NULL(fwnode->secondary)) - ret = fwnode_call_bool_op(fwnode->secondary, property_present, - propname); - return ret; + if (ret) + return ret; + + return fwnode_call_bool_op(fwnode->secondary, property_present, propname); } EXPORT_SYMBOL_GPL(fwnode_property_present); @@ -232,15 +234,16 @@ static int fwnode_property_read_int_array(const struct fwnode_handle *fwnode, { int ret; + if (IS_ERR_OR_NULL(fwnode)) + return -EINVAL; + ret = fwnode_call_int_op(fwnode, property_read_int_array, propname, elem_size, val, nval); - if (ret == -EINVAL && !IS_ERR_OR_NULL(fwnode) && - !IS_ERR_OR_NULL(fwnode->secondary)) - ret = fwnode_call_int_op( - fwnode->secondary, property_read_int_array, propname, - elem_size, val, nval); + if (ret != -EINVAL) + return ret; - return ret; + return fwnode_call_int_op(fwnode->secondary, property_read_int_array, propname, + elem_size, val, nval); } /** @@ -371,14 +374,16 @@ int fwnode_property_read_string_array(const struct fwnode_handle *fwnode, { int ret; + if (IS_ERR_OR_NULL(fwnode)) + return -EINVAL; + ret = fwnode_call_int_op(fwnode, property_read_string_array, propname, val, nval); - if (ret == -EINVAL && !IS_ERR_OR_NULL(fwnode) && - !IS_ERR_OR_NULL(fwnode->secondary)) - ret = fwnode_call_int_op(fwnode->secondary, - property_read_string_array, propname, - val, nval); - return ret; + if (ret != -EINVAL) + return ret; + + return fwnode_call_int_op(fwnode->secondary, property_read_string_array, propname, + val, nval); } EXPORT_SYMBOL_GPL(fwnode_property_read_string_array); @@ -480,15 +485,19 @@ int fwnode_property_get_reference_args(const struct fwnode_handle *fwnode, { int ret; + if (IS_ERR_OR_NULL(fwnode)) + return -ENOENT; + ret = fwnode_call_int_op(fwnode, get_reference_args, prop, nargs_prop, nargs, index, args); + if (ret == 0) + return ret; - if (ret < 0 && !IS_ERR_OR_NULL(fwnode) && - !IS_ERR_OR_NULL(fwnode->secondary)) - ret = fwnode_call_int_op(fwnode->secondary, get_reference_args, - prop, nargs_prop, nargs, index, args); + if (IS_ERR_OR_NULL(fwnode->secondary)) + return -ENOENT; - return ret; + return fwnode_call_int_op(fwnode->secondary, get_reference_args, prop, nargs_prop, + nargs, index, args); } EXPORT_SYMBOL_GPL(fwnode_property_get_reference_args); @@ -635,12 +644,13 @@ EXPORT_SYMBOL_GPL(fwnode_count_parents); struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwnode, unsigned int depth) { - unsigned int i; - fwnode_handle_get(fwnode); - for (i = 0; i < depth && fwnode; i++) + do { + if (depth-- == 0) + break; fwnode = fwnode_get_next_parent(fwnode); + } while (fwnode); return fwnode; } @@ -659,17 +669,17 @@ EXPORT_SYMBOL_GPL(fwnode_get_nth_parent); bool fwnode_is_ancestor_of(struct fwnode_handle *test_ancestor, struct fwnode_handle *test_child) { - if (!test_ancestor) + if (IS_ERR_OR_NULL(test_ancestor)) return false; fwnode_handle_get(test_child); - while (test_child) { + do { if (test_child == test_ancestor) { fwnode_handle_put(test_child); return true; } test_child = fwnode_get_next_parent(test_child); - } + } while (test_child); return false; } @@ -698,7 +708,7 @@ fwnode_get_next_available_child_node(const struct fwnode_handle *fwnode, { struct fwnode_handle *next_child = child; - if (!fwnode) + if (IS_ERR_OR_NULL(fwnode)) return NULL; do { @@ -722,16 +732,16 @@ struct fwnode_handle *device_get_next_child_node(struct device *dev, const struct fwnode_handle *fwnode = dev_fwnode(dev); struct fwnode_handle *next; + if (IS_ERR_OR_NULL(fwnode)) + return NULL; + /* Try to find a child in primary fwnode */ next = fwnode_get_next_child_node(fwnode, child); if (next) return next; /* When no more children in primary, continue with secondary */ - if (fwnode && !IS_ERR_OR_NULL(fwnode->secondary)) - next = fwnode_get_next_child_node(fwnode->secondary, child); - - return next; + return fwnode_get_next_child_node(fwnode->secondary, child); } EXPORT_SYMBOL_GPL(device_get_next_child_node); @@ -798,6 +808,9 @@ EXPORT_SYMBOL_GPL(fwnode_handle_put); */ bool fwnode_device_is_available(const struct fwnode_handle *fwnode) { + if (IS_ERR_OR_NULL(fwnode)) + return false; + if (!fwnode_has_op(fwnode, device_is_available)) return true; @@ -988,14 +1001,14 @@ fwnode_graph_get_next_endpoint(const struct fwnode_handle *fwnode, parent = fwnode_graph_get_port_parent(prev); else parent = fwnode; + if (IS_ERR_OR_NULL(parent)) + return NULL; ep = fwnode_call_ptr_op(parent, graph_get_next_endpoint, prev); + if (ep) + return ep; - if (IS_ERR_OR_NULL(ep) && - !IS_ERR_OR_NULL(parent) && !IS_ERR_OR_NULL(parent->secondary)) - ep = fwnode_graph_get_next_endpoint(parent->secondary, NULL); - - return ep; + return fwnode_graph_get_next_endpoint(parent->secondary, NULL); } EXPORT_SYMBOL_GPL(fwnode_graph_get_next_endpoint); diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 3a532ba66f6c..7defac04f9a3 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -148,12 +148,12 @@ struct fwnode_operations { int (*add_links)(struct fwnode_handle *fwnode); }; -#define fwnode_has_op(fwnode, op) \ - ((fwnode) && (fwnode)->ops && (fwnode)->ops->op) +#define fwnode_has_op(fwnode, op) \ + (!IS_ERR_OR_NULL(fwnode) && (fwnode)->ops && (fwnode)->ops->op) + #define fwnode_call_int_op(fwnode, op, ...) \ - (fwnode ? (fwnode_has_op(fwnode, op) ? \ - (fwnode)->ops->op(fwnode, ## __VA_ARGS__) : -ENXIO) : \ - -EINVAL) + (fwnode_has_op(fwnode, op) ? \ + (fwnode)->ops->op(fwnode, ## __VA_ARGS__) : (IS_ERR_OR_NULL(fwnode) ? -EINVAL : -ENXIO)) #define fwnode_call_bool_op(fwnode, op, ...) \ (fwnode_has_op(fwnode, op) ? \ -- 2.35.1