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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BDA90ECE562 for ; Fri, 21 Sep 2018 07:29:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6731421523 for ; Fri, 21 Sep 2018 07:29:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=bgdev-pl.20150623.gappssmtp.com header.i=@bgdev-pl.20150623.gappssmtp.com header.b="wedoI0Ga" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6731421523 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bgdev.pl Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389557AbeIUNRT (ORCPT ); Fri, 21 Sep 2018 09:17:19 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:37254 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389528AbeIUNRT (ORCPT ); Fri, 21 Sep 2018 09:17:19 -0400 Received: by mail-wr1-f68.google.com with SMTP id u12-v6so11787349wrr.4 for ; Fri, 21 Sep 2018 00:29:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bgdev-pl.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=hoddC+Dlb2GKPuc7IWS3Y2zKJ7N6bVfp66wSSHaZPhM=; b=wedoI0GaOk1fft9KPdfKQTJatgnlpJOHFZTUwUalyoKaSQUCBVGYntTkK1tnBKaWSO p+gqH/SHR5/FSwqMIKvNWyDCjHAU/J5kLIk2wq1tCImmMKLGf1hP3sIxhziv5w17sCdz 9SqcEDpsrWmeXhE7kiF/j9Vdu2fcW3WoUlsneeRNnXTdNylQ+0P68kF/uA1jSH1UGEKu sR353docIKiDGoxykJnF+ZnMr4AYS07UqTjunpSOJutitHZfCrbDAbdpYXlg0Qc2PTcO lwaM24IPLlprWSEQFkxNycrRY4EiE3Ql1rre7H9PrxcVIKbGw3RmSjJF6XKLIDljw3+P cDdw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=hoddC+Dlb2GKPuc7IWS3Y2zKJ7N6bVfp66wSSHaZPhM=; b=QU3id1SDqQEMLU6+V8PCrHVDzLI292f1W3c8tIzQfLWCoZ1oMOhCTuPOCtXMs2bb5z cVP/mR7MQ+bcGZk5nzDs2WJFxbymz9pGCwepc60f9Aqj4dYRvQtUEFGLENygptnUKw7u PrDGNLMjjAqlJd1tP7XJiqTCw5A7p5Xl9fcvhmFgitddLD98yDavfrsS1Zxue03f7BTE g5zANt1we7xHHVHqrIyKaYJCkrCBsMxFoN4u556RGIFKC5hGqqz2/Cs9H54EYioQv2lG zy4XxiSXCUNBl3A1UJ2qmq3amTMp2LsIVDvDV/qXS6Xv76zE5OWMYQP7c5je+FMCYjYs xciQ== X-Gm-Message-State: APzg51Dk8IDtjnWVLldp/ZsopmKML7o/NSTAx+ybRejP2dCX3FMO1pjS C279GIkyYjuajvkgAQiM3Mwryw== X-Google-Smtp-Source: ANB0Vdbk3aAH8sCSHOW2+wM9qLH7OlLkBrFJQOtd1JE94haxWdwyJGErlZPPRwswdDj/UHUyKetw2A== X-Received: by 2002:adf:b726:: with SMTP id l38-v6mr33391602wre.115.1537514982750; Fri, 21 Sep 2018 00:29:42 -0700 (PDT) Received: from brgl-bgdev.home ([2a01:cb1d:af:5b00:e837:b8d5:48c1:571b]) by smtp.gmail.com with ESMTPSA id d18-v6sm2841597wmb.33.2018.09.21.00.29.41 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 21 Sep 2018 00:29:42 -0700 (PDT) From: Bartosz Golaszewski To: Srinivas Kandagatla , "David S . Miller" , Mauro Carvalho Chehab , Greg Kroah-Hartman , Andrew Morton , Arnd Bergmann , Jonathan Corbet , Sekhar Nori , Kevin Hilman , David Lechner , Boris Brezillon , Andrew Lunn , Alban Bedel , Maxime Ripard , Chen-Yu Tsai Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Bartosz Golaszewski Subject: [PATCH v5 12/22] nvmem: remove the global cell list Date: Fri, 21 Sep 2018 09:29:11 +0200 Message-Id: <20180921072921.19387-13-brgl@bgdev.pl> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180921072921.19387-1-brgl@bgdev.pl> References: <20180921072921.19387-1-brgl@bgdev.pl> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Bartosz Golaszewski Nvmem subsystem keeps a global list of cells that, for non-DT systems, can only be referenced by cell name, which makes it impossible to have more than one nvmem device with cells named the same. This patch makes every nvmem device the owner of the list of its cells. This effectively removes the support for non-DT systems, but it will be reintroduced following a different approach in subsequent patches. This isn't a problem as support for board files in nvmem is currently broken anyway: any user that would try to get an nvmem cell from the global cell list would remove the cell after the calling nvmem_cell_put(). This can cause anything from a subsequent user not being able to get the cell to double free errors if more users hold reference to the same cell at the same time. Fortunately there are no such users which allows us to rework this part. Signed-off-by: Bartosz Golaszewski --- drivers/nvmem/core.c | 64 +++++++++++--------------------------------- 1 file changed, 15 insertions(+), 49 deletions(-) diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index bd14d04782cd..ee794613024c 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -38,6 +38,7 @@ struct nvmem_device { int flags; struct bin_attribute eeprom; struct device *base_dev; + struct list_head cells; nvmem_reg_read_t reg_read; nvmem_reg_write_t reg_write; void *priv; @@ -58,9 +59,6 @@ struct nvmem_cell { static DEFINE_MUTEX(nvmem_mutex); static DEFINE_IDA(nvmem_ida); -static LIST_HEAD(nvmem_cells); -static DEFINE_MUTEX(nvmem_cells_mutex); - #ifdef CONFIG_DEBUG_LOCK_ALLOC static struct lock_class_key eeprom_lock_key; #endif @@ -282,28 +280,11 @@ static struct nvmem_device *of_nvmem_find(struct device_node *nvmem_np) return to_nvmem_device(d); } -static struct nvmem_cell *nvmem_find_cell(const char *cell_id) -{ - struct nvmem_cell *p; - - mutex_lock(&nvmem_cells_mutex); - - list_for_each_entry(p, &nvmem_cells, node) - if (!strcmp(p->name, cell_id)) { - mutex_unlock(&nvmem_cells_mutex); - return p; - } - - mutex_unlock(&nvmem_cells_mutex); - - return NULL; -} - static void nvmem_cell_drop(struct nvmem_cell *cell) { - mutex_lock(&nvmem_cells_mutex); + mutex_lock(&nvmem_mutex); list_del(&cell->node); - mutex_unlock(&nvmem_cells_mutex); + mutex_unlock(&nvmem_mutex); kfree(cell); } @@ -311,16 +292,15 @@ static void nvmem_device_remove_all_cells(const struct nvmem_device *nvmem) { struct nvmem_cell *cell, *p; - list_for_each_entry_safe(cell, p, &nvmem_cells, node) - if (cell->nvmem == nvmem) - nvmem_cell_drop(cell); + list_for_each_entry_safe(cell, p, &nvmem->cells, node) + nvmem_cell_drop(cell); } static void nvmem_cell_add(struct nvmem_cell *cell) { - mutex_lock(&nvmem_cells_mutex); - list_add_tail(&cell->node, &nvmem_cells); - mutex_unlock(&nvmem_cells_mutex); + mutex_lock(&nvmem_mutex); + list_add_tail(&cell->node, &cell->nvmem->cells); + mutex_unlock(&nvmem_mutex); } static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem, @@ -465,6 +445,7 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config) } kref_init(&nvmem->refcnt); + INIT_LIST_HEAD(&nvmem->cells); nvmem->id = rval; nvmem->owner = config->owner; @@ -626,29 +607,14 @@ static struct nvmem_device *__nvmem_device_get(struct device_node *np, { struct nvmem_device *nvmem = NULL; - mutex_lock(&nvmem_mutex); - - if (np) { - nvmem = of_nvmem_find(np); - if (!nvmem) { - mutex_unlock(&nvmem_mutex); - return ERR_PTR(-EPROBE_DEFER); - } - } else { - struct nvmem_cell *cell = nvmem_find_cell(cell_id); - - if (cell) { - nvmem = cell->nvmem; - *cellp = cell; - } - - if (!nvmem) { - mutex_unlock(&nvmem_mutex); - return ERR_PTR(-ENOENT); - } - } + if (!np) + return ERR_PTR(-ENOENT); + mutex_lock(&nvmem_mutex); + nvmem = of_nvmem_find(np); mutex_unlock(&nvmem_mutex); + if (!nvmem) + return ERR_PTR(-EPROBE_DEFER); if (!try_module_get(nvmem->owner)) { dev_err(&nvmem->dev, -- 2.18.0