From patchwork Tue Dec 22 00:44:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Isaac J. Manjarres" X-Patchwork-Id: 346675 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=-16.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 7A64DC43381 for ; Tue, 22 Dec 2020 00:46:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5076222B2B for ; Tue, 22 Dec 2020 00:46:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726261AbgLVApr (ORCPT ); Mon, 21 Dec 2020 19:45:47 -0500 Received: from so254-31.mailgun.net ([198.61.254.31]:13009 "EHLO so254-31.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726101AbgLVApq (ORCPT ); Mon, 21 Dec 2020 19:45:46 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1608597927; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=bYabydo/dXbRQkL5qXIuDQBWRKY+jGONTXRs3liUi6M=; b=UC+UFZFPVdVfuidL+tApd0uIR6GQ0B5mwXtIUp9UYwFQiE0O0Poxxsy1Lj7+XBBl3otqW8He VasQUbxJ7uvZo1MDy0YxgwX2HUDnP4xQTWRhHA0yrSgaU3FgHF2CsMbMEk+WHViZXrIhNrw+ KEcOQbWWMnRAExDyuReAK2ax0zM= X-Mailgun-Sending-Ip: 198.61.254.31 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-east-1.postgun.com with SMTP id 5fe14183b00c0d7ad406b461 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 22 Dec 2020 00:44:51 GMT Sender: isaacm=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id C7535C43466; Tue, 22 Dec 2020 00:44:50 +0000 (UTC) Received: from isaacm-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: isaacm) by smtp.codeaurora.org (Postfix) with ESMTPSA id 3F294C43464; Tue, 22 Dec 2020 00:44:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3F294C43464 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=isaacm@codeaurora.org From: "Isaac J. Manjarres" To: iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, freedreno@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org Cc: "Isaac J. Manjarres" , will@kernel.org, joro@8bytes.org, pdaly@codeaurora.org, pratikp@codeaurora.org, kernel-team@android.com, robin.murphy@arm.com Subject: [PATCH v2 2/7] iommu/io-pgtable: Add refcounting for io-pgtable format modules Date: Mon, 21 Dec 2020 16:44:31 -0800 Message-Id: <1608597876-32367-3-git-send-email-isaacm@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1608597876-32367-1-git-send-email-isaacm@codeaurora.org> References: <1608597876-32367-1-git-send-email-isaacm@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In preparation for modularizing io-pgtable formats, add support for reference counting the io-pgtable format modules to ensure that the modules are not unloaded while they are in use. Signed-off-by: Isaac J. Manjarres --- drivers/iommu/io-pgtable-arm-v7s.c | 1 + drivers/iommu/io-pgtable-arm.c | 5 +++++ drivers/iommu/io-pgtable.c | 12 ++++++++++-- include/linux/io-pgtable.h | 2 ++ 4 files changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c index 89aad2f..a5cb755a 100644 --- a/drivers/iommu/io-pgtable-arm-v7s.c +++ b/drivers/iommu/io-pgtable-arm-v7s.c @@ -840,6 +840,7 @@ static struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns = { .fmt = ARM_V7S, .alloc = arm_v7s_alloc_pgtable, .free = arm_v7s_free_pgtable, + .owner = THIS_MODULE, }; #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S_SELFTEST diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index ff0ea2f..e8b1e34 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -1049,26 +1049,31 @@ static struct io_pgtable_init_fns io_pgtable_arm_lpae_init_fns[] = { .fmt = ARM_32_LPAE_S1, .alloc = arm_32_lpae_alloc_pgtable_s1, .free = arm_lpae_free_pgtable, + .owner = THIS_MODULE, }, { .fmt = ARM_32_LPAE_S2, .alloc = arm_32_lpae_alloc_pgtable_s2, .free = arm_lpae_free_pgtable, + .owner = THIS_MODULE, }, { .fmt = ARM_64_LPAE_S1, .alloc = arm_64_lpae_alloc_pgtable_s1, .free = arm_lpae_free_pgtable, + .owner = THIS_MODULE, }, { .fmt = ARM_64_LPAE_S2, .alloc = arm_64_lpae_alloc_pgtable_s2, .free = arm_lpae_free_pgtable, + .owner = THIS_MODULE, }, { .fmt = ARM_MALI_LPAE, .alloc = arm_mali_lpae_alloc_pgtable, .free = arm_lpae_free_pgtable, + .owner = THIS_MODULE, }, }; diff --git a/drivers/iommu/io-pgtable.c b/drivers/iommu/io-pgtable.c index 2c6eb2e..cc83542 100644 --- a/drivers/iommu/io-pgtable.c +++ b/drivers/iommu/io-pgtable.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -52,9 +53,14 @@ struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt, if (!fns) return NULL; + if (!try_module_get(fns->owner)) + return NULL; + iop = fns->alloc(cfg, cookie); - if (!iop) + if (!iop) { + module_put(fns->owner); return NULL; + } iop->fmt = fmt; iop->cookie = cookie; @@ -79,8 +85,10 @@ void free_io_pgtable_ops(struct io_pgtable_ops *ops) iop = io_pgtable_ops_to_pgtable(ops); io_pgtable_tlb_flush_all(iop); fns = io_pgtable_get_init_fns(iop->fmt); - if (fns) + if (fns) { fns->free(iop); + module_put(fns->owner); + } } EXPORT_SYMBOL_GPL(free_io_pgtable_ops); diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h index 45b367ce..a03b262 100644 --- a/include/linux/io-pgtable.h +++ b/include/linux/io-pgtable.h @@ -169,11 +169,13 @@ struct io_pgtable_ops { * @fmt: The page table format. * @alloc: Allocate a set of page tables described by cfg. * @free: Free the page tables associated with iop. + * @owner: Driver module providing these ops. */ struct io_pgtable_init_fns { enum io_pgtable_fmt fmt; struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie); void (*free)(struct io_pgtable *iop); + struct module *owner; }; /**