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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 7CF57C433E0 for ; Thu, 18 Jun 2020 15:55:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4713520732 for ; Thu, 18 Jun 2020 15:55:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Oiur89z1"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="Eds4e2o9" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4713520732 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=j5bZwIsLtWbIYeQlqv77Zvvz/FNfy17H6HF3TTpPV1I=; b=Oiur89z1nBszhW TgHsB2q05OQLCNrbnvXilYTC4CZJ4aUIgW4/K3Z8a40tmNgOvIqe8HweTk/h0jU6hrh9Pnc6Eua0E mkj0NQ4tx3lGKOopmVMY3pMSuMypQvsaryHZIAzpJbUHaXOafuKgUW67piHHgRxi1n0EXgTXdTVXP /BFNejxk/wWOxzi1QByu3nhHX3L9x/srFAY2l/7ZXUNoSWDP+1UYpPydTk+D7Vauo5khishNoLiLu RnOA6bQPOyTdDOQFtSWR+kAxCjSJ7JXr47iRHEeYhvXVVAG7dxO9+6s5N06J7ywOCNhH1msWw2rCi HMLWY0TPq4jfdmkSKhUg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jlwt8-0006fz-BD; Thu, 18 Jun 2020 15:55:38 +0000 Received: from mail-ej1-x643.google.com ([2a00:1450:4864:20::643]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jlwqJ-00029W-0n for linux-arm-kernel@lists.infradead.org; Thu, 18 Jun 2020 15:52:50 +0000 Received: by mail-ej1-x643.google.com with SMTP id dp18so6926086ejc.8 for ; Thu, 18 Jun 2020 08:52:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=gANJ9nXJh01yt9NJy6mJRUbndSE80vIrxk0QteKIq3c=; b=Eds4e2o9/aTlytifgQchMEkJmVJnHukU0ovaep4b99cT1h6zth+zUqp366TT6K7ePX HiZEqi5WIama9YvlIAens9d1oSuRcu30EdLiupH19lT8Hmm2muD9gKIAMgXLTT8oZzjY MoyoHHPnrcr8cOojysoVY47yfdgPaVRYmZmo+khdV4Ej00BOefC8o/w6f/PYTJyS6JMS IE97PCTm2L9rvU65hRt0iESOfgfc1BzLFCJZHQEDWvQTL3BUfPf06ylKZClOTGVvHCHR HxJDIw/+s/Qhsbwm5tathG8DD43vy8bx/z/kb1lxFBK35YaCkkejan7zgAl8K15t3TWZ HQ7w== 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:mime-version:content-transfer-encoding; bh=gANJ9nXJh01yt9NJy6mJRUbndSE80vIrxk0QteKIq3c=; b=VY30fSVziyoHNxLbKRWw+9ElPQvHS/da6KN+Bkdekb+8Z82jE0N51TVN14aUSuOTk0 jf/rTcFq7VC610HOzgyfigdTgMynYbWm6dA6i7DWfhhvzD1dxjckrEkOmyKFbON+BBHd qPVOraa4URb4lMsHYUZp3yyl7fwFgyex9Z57aWDohEabXajkyrK8HELg1vy+ed6/1RGh +fhYjXP9n4zwL55Km3zgnZq8fg4tUlmRvn+/DPUBUUNXmm3PG6Z8IppvfcYMB2XgWx7s XiV9hBdSIDtLYosQzcqDJJHMS7Yc/+e/Tp7cQrjxgqtuRYB9QsRqfeZVA8a+XWI6BALR UGFQ== X-Gm-Message-State: AOAM531Ws57k9UZfaCNJwMyU2nj55i/jcNvugj/oNL52lyJ07H0iejJZ Tf8oKjJGPqbJS6ytFdLkZbYOyA== X-Google-Smtp-Source: ABdhPJwyzOwFmlJDohdbHbSJOb408dno2oi+63HZld2Ti01+pRXVJHbN4UECF6xp5+TKBsOTjUOPvw== X-Received: by 2002:a17:906:68c5:: with SMTP id y5mr4450793ejr.436.1592495560894; Thu, 18 Jun 2020 08:52:40 -0700 (PDT) Received: from localhost.localdomain ([2001:1715:4e26:a7e0:116c:c27a:3e7f:5eaf]) by smtp.gmail.com with ESMTPSA id 63sm2402267edy.8.2020.06.18.08.52.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Jun 2020 08:52:40 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Subject: [PATCH v8 02/12] iommu/ioasid: Add ioasid references Date: Thu, 18 Jun 2020 17:51:15 +0200 Message-Id: <20200618155125.1548969-3-jean-philippe@linaro.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200618155125.1548969-1-jean-philippe@linaro.org> References: <20200618155125.1548969-1-jean-philippe@linaro.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200618_085243_093078_7CEBBFC0 X-CRM114-Status: GOOD ( 16.98 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fenghua.yu@intel.com, jacob.jun.pan@linux.intel.com, Jean-Philippe Brucker , catalin.marinas@arm.com, joro@8bytes.org, robin.murphy@arm.com, hch@infradead.org, zhengxiang9@huawei.com, Jonathan.Cameron@huawei.com, zhangfei.gao@linaro.org, will@kernel.org, xuzaibo@huawei.com, baolu.lu@linux.intel.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Let IOASID users take references to existing ioasids with ioasid_get(). ioasid_put() drops a reference and only frees the ioasid when its reference number is zero. It returns true if the ioasid was freed. For drivers that don't call ioasid_get(), ioasid_put() is the same as ioasid_free(). Reviewed-by: Lu Baolu Signed-off-by: Jean-Philippe Brucker --- include/linux/ioasid.h | 10 ++++++++-- drivers/iommu/intel/iommu.c | 4 ++-- drivers/iommu/intel/svm.c | 6 +++--- drivers/iommu/ioasid.c | 38 +++++++++++++++++++++++++++++++++---- 4 files changed, 47 insertions(+), 11 deletions(-) diff --git a/include/linux/ioasid.h b/include/linux/ioasid.h index 6f000d7a0ddcd..e9dacd4b9f6bb 100644 --- a/include/linux/ioasid.h +++ b/include/linux/ioasid.h @@ -34,7 +34,8 @@ struct ioasid_allocator_ops { #if IS_ENABLED(CONFIG_IOASID) ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, ioasid_t max, void *private); -void ioasid_free(ioasid_t ioasid); +void ioasid_get(ioasid_t ioasid); +bool ioasid_put(ioasid_t ioasid); void *ioasid_find(struct ioasid_set *set, ioasid_t ioasid, bool (*getter)(void *)); int ioasid_register_allocator(struct ioasid_allocator_ops *allocator); @@ -48,10 +49,15 @@ static inline ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, return INVALID_IOASID; } -static inline void ioasid_free(ioasid_t ioasid) +static inline void ioasid_get(ioasid_t ioasid) { } +static inline bool ioasid_put(ioasid_t ioasid) +{ + return false; +} + static inline void *ioasid_find(struct ioasid_set *set, ioasid_t ioasid, bool (*getter)(void *)) { diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 9129663a7406b..a5840b8ef14b7 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -5131,7 +5131,7 @@ static void auxiliary_unlink_device(struct dmar_domain *domain, domain->auxd_refcnt--; if (!domain->auxd_refcnt && domain->default_pasid > 0) - ioasid_free(domain->default_pasid); + ioasid_put(domain->default_pasid); } static int aux_domain_add_dev(struct dmar_domain *domain, @@ -5193,7 +5193,7 @@ static int aux_domain_add_dev(struct dmar_domain *domain, spin_unlock(&iommu->lock); spin_unlock_irqrestore(&device_domain_lock, flags); if (!domain->auxd_refcnt && domain->default_pasid > 0) - ioasid_free(domain->default_pasid); + ioasid_put(domain->default_pasid); return ret; } diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index 6c87c807a0abb..b078a697c42e8 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -546,7 +546,7 @@ intel_svm_bind_mm(struct device *dev, int flags, struct svm_dev_ops *ops, if (mm) { ret = mmu_notifier_register(&svm->notifier, mm); if (ret) { - ioasid_free(svm->pasid); + ioasid_put(svm->pasid); kfree(svm); kfree(sdev); goto out; @@ -564,7 +564,7 @@ intel_svm_bind_mm(struct device *dev, int flags, struct svm_dev_ops *ops, if (ret) { if (mm) mmu_notifier_unregister(&svm->notifier, mm); - ioasid_free(svm->pasid); + ioasid_put(svm->pasid); kfree(svm); kfree(sdev); goto out; @@ -639,7 +639,7 @@ static int intel_svm_unbind_mm(struct device *dev, int pasid) kfree_rcu(sdev, rcu); if (list_empty(&svm->devs)) { - ioasid_free(svm->pasid); + ioasid_put(svm->pasid); if (svm->mm) mmu_notifier_unregister(&svm->notifier, svm->mm); list_del(&svm->list); diff --git a/drivers/iommu/ioasid.c b/drivers/iommu/ioasid.c index 0f8dd377aada3..50ee27bbd04ec 100644 --- a/drivers/iommu/ioasid.c +++ b/drivers/iommu/ioasid.c @@ -2,7 +2,7 @@ /* * I/O Address Space ID allocator. There is one global IOASID space, split into * subsets. Users create a subset with DECLARE_IOASID_SET, then allocate and - * free IOASIDs with ioasid_alloc and ioasid_free. + * free IOASIDs with ioasid_alloc and ioasid_put. */ #include #include @@ -15,6 +15,7 @@ struct ioasid_data { struct ioasid_set *set; void *private; struct rcu_head rcu; + refcount_t refs; }; /* @@ -314,6 +315,7 @@ ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, ioasid_t max, data->set = set; data->private = private; + refcount_set(&data->refs, 1); /* * Custom allocator needs allocator data to perform platform specific @@ -346,11 +348,34 @@ ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, ioasid_t max, EXPORT_SYMBOL_GPL(ioasid_alloc); /** - * ioasid_free - Free an IOASID + * ioasid_get - obtain a reference to the IOASID + */ +void ioasid_get(ioasid_t ioasid) +{ + struct ioasid_data *ioasid_data; + + spin_lock(&ioasid_allocator_lock); + ioasid_data = xa_load(&active_allocator->xa, ioasid); + if (ioasid_data) + refcount_inc(&ioasid_data->refs); + else + WARN_ON(1); + spin_unlock(&ioasid_allocator_lock); +} +EXPORT_SYMBOL_GPL(ioasid_get); + +/** + * ioasid_put - Release a reference to an ioasid * @ioasid: the ID to remove + * + * Put a reference to the IOASID, free it when the number of references drops to + * zero. + * + * Return: %true if the IOASID was freed, %false otherwise. */ -void ioasid_free(ioasid_t ioasid) +bool ioasid_put(ioasid_t ioasid) { + bool free = false; struct ioasid_data *ioasid_data; spin_lock(&ioasid_allocator_lock); @@ -360,6 +385,10 @@ void ioasid_free(ioasid_t ioasid) goto exit_unlock; } + free = refcount_dec_and_test(&ioasid_data->refs); + if (!free) + goto exit_unlock; + active_allocator->ops->free(ioasid, active_allocator->ops->pdata); /* Custom allocator needs additional steps to free the xa element */ if (active_allocator->flags & IOASID_ALLOCATOR_CUSTOM) { @@ -369,8 +398,9 @@ void ioasid_free(ioasid_t ioasid) exit_unlock: spin_unlock(&ioasid_allocator_lock); + return free; } -EXPORT_SYMBOL_GPL(ioasid_free); +EXPORT_SYMBOL_GPL(ioasid_put); /** * ioasid_find - Find IOASID data -- 2.27.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel