From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 91536101EC for ; Wed, 14 Jun 2023 15:44:47 +0000 (UTC) Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-56ff81be091so12265037b3.0 for ; Wed, 14 Jun 2023 08:44:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1686757486; x=1689349486; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=tvomj7iW2UACU6/yECNbFWEXmb4EH1aV19zctsWiNw0=; b=vuL1XrQpU5Uq0e2ygjk0DfQm99VPq2z9YNT+avIv27XZ5urDEgwpmKbViVzjQ8Ors2 T0rraZDZVM0ODSgkQTw6g6hdTWSyZHC/ZwHObRZETsh7v9KsqI7mfjRVjTddqwb75Yd6 PkKi9NkGSgecoW5IThOwn0gGyOxQIy0qaPS8Ued69ldHUGXC3bEZuqzTL/jNRXCrcJi3 uAxDiKxWDeKXd8Icj/EZsPQK5O6GRp7wJwAZct0hM+oyxo3a3VP2+SBs18GWULEH6AcA +Q3vGN3bOvN8pQVCjBFeK+N8axcpPszN+TMygeq+12fShtLMkNw5EOWGCZf8F5q4Py43 k0CQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686757486; x=1689349486; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=tvomj7iW2UACU6/yECNbFWEXmb4EH1aV19zctsWiNw0=; b=fngRaPQ4T4i421ijQC6zWtxrA9HrhpIZD7TbRwWkhM4vDhph7g+kP+W3PJdEjcgrHS +/DwyspqccY+CJNnY3bWQjOeKy+6NJ+pbIuMG6zOEY77FN7n7s7eQLF5xvPJoR5cdDLl 9LBT1UzJ4K+JBeHHE1DFYPGMOb90GHgmlIRDR65PZ17cwRVsir/ElruDfB/HZQqLtjmr 8ipYUlpR0oo7s2QXnGoTabmcPzhmaow0gp2mye7RGlEGPjQQx8BzpTWZfwHs+OII4Oys kwRYOl2s1fHo6Et6I95VQT1ZQXZDojwMWGp2sfOGTMUrzlQo2VcGHi69xIuMAf6WyoYb XYOA== X-Gm-Message-State: AC+VfDxfitSDw248o1cDIVofDTsf/PkA7DV3A2Vt4IGVcARx3WCxo3jR u22HTHka+uMTHfVdfxBypW7+53js1heC X-Google-Smtp-Source: ACHHUZ6PWgAWHwE/x5mre24ZvBjK+WBUn1h6Ifenl3MHyaJYnWLa0SO3LQyqPPJbjhH7MP8WEYsBnUmWbutp X-Received: from mshavit.ntc.corp.google.com ([2401:fa00:95:20c:c6e6:49bf:5c44:5965]) (user=mshavit job=sendgmr) by 2002:a81:440c:0:b0:56d:791:d1a4 with SMTP id r12-20020a81440c000000b0056d0791d1a4mr1051771ywa.7.1686757486567; Wed, 14 Jun 2023 08:44:46 -0700 (PDT) Date: Wed, 14 Jun 2023 23:42:02 +0800 In-Reply-To: <20230614154304.2860121-1-mshavit@google.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20230614154304.2860121-1-mshavit@google.com> X-Mailer: git-send-email 2.41.0.162.gfafddb0af9-goog Message-ID: <20230614154304.2860121-11-mshavit@google.com> Subject: [PATCH v3 10/13] iommu/arm-smmu-v3-sva: Remove bond refcount From: Michael Shavit To: Will Deacon , Robin Murphy , Joerg Roedel Cc: Michael Shavit , jean-philippe@linaro.org, nicolinc@nvidia.com, jgg@nvidia.com, baolu.lu@linux.intel.com, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" The iommu-sva framework checks if a bond between a device and mm already exists and handles refcounting at the iommu_domain level. __arm_smmu_sva_bind is therefore only called once for a device/mm pair. Signed-off-by: Michael Shavit --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c index d07c08b53c5cf..20301d0a2c0b0 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c @@ -29,7 +29,6 @@ struct arm_smmu_bond { struct mm_struct *mm; struct arm_smmu_mmu_notifier *smmu_mn; struct list_head list; - refcount_t refs; }; #define sva_to_bond(handle) \ @@ -377,21 +376,12 @@ __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm) if (!master || !master->sva_enabled) return ERR_PTR(-ENODEV); - /* If bind() was already called for this {dev, mm} pair, reuse it. */ - list_for_each_entry(bond, &master->bonds, list) { - if (bond->mm == mm) { - refcount_inc(&bond->refs); - return &bond->sva; - } - } - bond = kzalloc(sizeof(*bond), GFP_KERNEL); if (!bond) return ERR_PTR(-ENOMEM); bond->mm = mm; bond->sva.dev = dev; - refcount_set(&bond->refs, 1); bond->smmu_mn = arm_smmu_mmu_notifier_get(smmu_domain, mm); if (IS_ERR(bond->smmu_mn)) { @@ -570,7 +560,7 @@ void arm_smmu_sva_remove_dev_pasid(struct iommu_domain *domain, } } - if (!WARN_ON(!bond) && refcount_dec_and_test(&bond->refs)) { + if (!WARN_ON(!bond)) { list_del(&bond->list); arm_smmu_mmu_notifier_put(bond->smmu_mn); kfree(bond); -- 2.41.0.162.gfafddb0af9-goog