Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
Date:   Fri, 25 Mar 2022 11:46:09 -0700
In-Reply-To: <20220325184609.4059963-1-rajatja@google.com>
Message-Id: <20220325184609.4059963-2-rajatja@google.com>
Mime-Version: 1.0
References: <20220325184609.4059963-1-rajatja@google.com>
Subject: [PATCH v5 2/2] PCI: Rename pci_dev->untrusted to pci_dev->untrusted_dma
From:   Rajat Jain <rajatja@google.com>
To:     "Rafael J. Wysocki" <rafael@kernel.org>,
        Len Brown <lenb@kernel.org>, linux-pci@vger.kernel.org,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Bjorn Helgaas <helgaas@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Rajat Jain <rajatxjain@gmail.com>,
        Dmitry Torokhov <dtor@google.com>,
        Jesse Barnes <jsbarnes@google.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        Pavel Machek <pavel@denx.de>,
        "Oliver O'Halloran" <oohall@gmail.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        David Woodhouse <dwmw2@infradead.org>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        iommu@lists.linux-foundation.org
Cc:     Rajat Jain <rajatja@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Rename the field to make it more clear, that the device can execute DMA
attacks on the system, and thus the system may need protection from
such attacks from this device.

No functional change intended.

Signed-off-by: Rajat Jain <rajatja@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
v5: Use "untrusted_dma" as property name, based on feedback.
    Reorder the patches in the series.
v4: Initial version, created based on comments on other patch

 drivers/iommu/dma-iommu.c   | 6 +++---
 drivers/iommu/intel/iommu.c | 2 +-
 drivers/iommu/iommu.c       | 2 +-
 drivers/pci/ats.c           | 2 +-
 drivers/pci/pci-acpi.c      | 2 +-
 drivers/pci/pci.c           | 2 +-
 drivers/pci/probe.c         | 8 ++++----
 drivers/pci/quirks.c        | 2 +-
 include/linux/pci.h         | 5 +++--
 9 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index d85d54f2b549..7cbe300fe907 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -497,14 +497,14 @@ static int iova_reserve_iommu_regions(struct device *dev,
 	return ret;
 }
 
-static bool dev_is_untrusted(struct device *dev)
+static bool dev_has_untrusted_dma(struct device *dev)
 {
-	return dev_is_pci(dev) && to_pci_dev(dev)->untrusted;
+	return dev_is_pci(dev) && to_pci_dev(dev)->untrusted_dma;
 }
 
 static bool dev_use_swiotlb(struct device *dev)
 {
-	return IS_ENABLED(CONFIG_SWIOTLB) && dev_is_untrusted(dev);
+	return IS_ENABLED(CONFIG_SWIOTLB) && dev_has_untrusted_dma(dev);
 }
 
 /**
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 92fea3fbbb11..9246b7c9ab46 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5570,7 +5570,7 @@ intel_iommu_enable_nesting(struct iommu_domain *domain)
  */
 static bool risky_device(struct pci_dev *pdev)
 {
-	if (pdev->untrusted) {
+	if (pdev->untrusted_dma) {
 		pci_info(pdev,
 			 "Skipping IOMMU quirk for dev [%04X:%04X] on untrusted PCI link\n",
 			 pdev->vendor, pdev->device);
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 8b86406b7162..79fb66af2e68 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1522,7 +1522,7 @@ static int iommu_get_def_domain_type(struct device *dev)
 {
 	const struct iommu_ops *ops = dev->bus->iommu_ops;
 
-	if (dev_is_pci(dev) && to_pci_dev(dev)->untrusted)
+	if (dev_is_pci(dev) && to_pci_dev(dev)->untrusted_dma)
 		return IOMMU_DOMAIN_DMA;
 
 	if (ops->def_domain_type)
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index c967ad6e2626..477c16ba9341 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -42,7 +42,7 @@ bool pci_ats_supported(struct pci_dev *dev)
 	if (!dev->ats_cap)
 		return false;
 
-	return (dev->untrusted == 0);
+	return (dev->untrusted_dma == 0);
 }
 EXPORT_SYMBOL_GPL(pci_ats_supported);
 
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 378e05096c52..1d5a284c3661 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -1362,7 +1362,7 @@ static void pci_acpi_check_for_dma_protection(struct pci_dev *dev)
 		return;
 
 	if (val)
-		dev->untrusted = 1;
+		dev->untrusted_dma = 1;
 }
 
 void pci_acpi_setup(struct device *dev, struct acpi_device *adev)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 9ecce435fb3f..1fb0eb8646c8 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -958,7 +958,7 @@ static void pci_std_enable_acs(struct pci_dev *dev)
 	ctrl |= (cap & PCI_ACS_UF);
 
 	/* Enable Translation Blocking for external devices and noats */
-	if (pci_ats_disabled() || dev->external_facing || dev->untrusted)
+	if (pci_ats_disabled() || dev->external_facing || dev->untrusted_dma)
 		ctrl |= (cap & PCI_ACS_TB);
 
 	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 17a969942d37..d2a9b26fcede 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1587,7 +1587,7 @@ static void set_pcie_thunderbolt(struct pci_dev *dev)
 		dev->is_thunderbolt = 1;
 }
 
-static void set_pcie_untrusted(struct pci_dev *dev)
+static void pci_set_untrusted_dma(struct pci_dev *dev)
 {
 	struct pci_dev *parent;
 
@@ -1596,8 +1596,8 @@ static void set_pcie_untrusted(struct pci_dev *dev)
 	 * untrusted as well.
 	 */
 	parent = pci_upstream_bridge(dev);
-	if (parent && (parent->untrusted || parent->external_facing))
-		dev->untrusted = true;
+	if (parent && (parent->untrusted_dma || parent->external_facing))
+		dev->untrusted_dma = true;
 }
 
 static void pci_set_removable(struct pci_dev *dev)
@@ -1862,7 +1862,7 @@ int pci_setup_device(struct pci_dev *dev)
 	/* Need to have dev->cfg_size ready */
 	set_pcie_thunderbolt(dev);
 
-	set_pcie_untrusted(dev);
+	pci_set_untrusted_dma(dev);
 
 	/* "Unknown power state" */
 	dev->current_state = PCI_UNKNOWN;
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 5f46fed01e6c..7ca3c2cdfb20 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -5134,7 +5134,7 @@ static int pci_quirk_enable_intel_spt_pch_acs(struct pci_dev *dev)
 	ctrl |= (cap & PCI_ACS_CR);
 	ctrl |= (cap & PCI_ACS_UF);
 
-	if (pci_ats_disabled() || dev->external_facing || dev->untrusted)
+	if (pci_ats_disabled() || dev->external_facing || dev->untrusted_dma)
 		ctrl |= (cap & PCI_ACS_TB);
 
 	pci_write_config_dword(dev, pos + INTEL_SPT_ACS_CTRL, ctrl);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 678fecdf6b81..b7c5fede0b93 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -444,13 +444,14 @@ struct pci_dev {
 	unsigned int	shpc_managed:1;		/* SHPC owned by shpchp */
 	unsigned int	is_thunderbolt:1;	/* Thunderbolt controller */
 	/*
-	 * Devices marked being untrusted are the ones that can potentially
+	 * Devices marked with untrusted_dma are the ones that can potentially
 	 * execute DMA attacks and similar. They are typically connected
 	 * through external ports such as Thunderbolt but not limited to
 	 * that. When an IOMMU is enabled they should be getting full
 	 * mappings to make sure they cannot access arbitrary memory.
 	 */
-	unsigned int	untrusted:1;
+	unsigned int	untrusted_dma:1;
+
 	/*
 	 * Info from the platform, e.g., ACPI or device tree, may mark a
 	 * device as "external-facing".  An external-facing device is
-- 
2.35.1.1021.g381101b075-goog