linux-kernel - [PATCH v2 17/22] iommu/arm-smmu-v3-iommufd: Support implementation-defined hw

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <56f048cdc9cd8bf1569434633d709d07a78e9430.1745646960.git.nicolinc@nvidia.com>
Date: Fri, 25 Apr 2025 22:58:12 -0700
From: Nicolin Chen <nicolinc@...dia.com>
To: <jgg@...dia.com>, <kevin.tian@...el.com>, <corbet@....net>,
	<will@...nel.org>
CC: <bagasdotme@...il.com>, <robin.murphy@....com>, <joro@...tes.org>,
	<thierry.reding@...il.com>, <vdumpa@...dia.com>, <jonathanh@...dia.com>,
	<shuah@...nel.org>, <jsnitsel@...hat.com>, <nathan@...nel.org>,
	<peterz@...radead.org>, <yi.l.liu@...el.com>, <mshavit@...gle.com>,
	<praan@...gle.com>, <zhangzekun11@...wei.com>, <iommu@...ts.linux.dev>,
	<linux-doc@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>, <linux-tegra@...r.kernel.org>,
	<linux-kselftest@...r.kernel.org>, <patches@...ts.linux.dev>,
	<mochs@...dia.com>, <alok.a.tiwari@...cle.com>, <vasant.hegde@....com>
Subject: [PATCH v2 17/22] iommu/arm-smmu-v3-iommufd: Support implementation-defined hw_info

Repurpose the @__reserved field in the struct iommu_hw_info_arm_smmuv3,
to an HW implementation-defined field @impl.

This will be used by Tegra241 CMDQV implementation on top of a standard
ARM SMMUv3 IOMMU. The @impl will be only valid if @flags is set with an
implementation-defined flag.

Thus in the driver-level, add an hw_info impl op that will return such
a flag to use the impl field.

Signed-off-by: Nicolin Chen <nicolinc@...dia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h      |  1 +
 include/uapi/linux/iommufd.h                     |  4 ++--
 .../iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c  | 16 +++++++++++++---
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index a5835af72417..bab7a9ce1283 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -726,6 +726,7 @@ struct arm_smmu_impl_ops {
 		struct arm_smmu_domain *smmu_domain, struct iommufd_ctx *ictx,
 		unsigned int viommu_type,
 		const struct iommu_user_data *user_data);
+	u32 (*hw_info)(struct arm_smmu_device *smmu, u32 *impl);
 };
 
 /* An SMMUv3 instance */
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 06a763fda47f..b2614f0f1547 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -554,7 +554,7 @@ struct iommu_hw_info_vtd {
  *                                   (IOMMU_HW_INFO_TYPE_ARM_SMMUV3)
  *
  * @flags: Must be set to 0
- * @__reserved: Must be 0
+ * @impl: Must be 0
  * @idr: Implemented features for ARM SMMU Non-secure programming interface
  * @iidr: Information about the implementation and implementer of ARM SMMU,
  *        and architecture version supported
@@ -585,7 +585,7 @@ struct iommu_hw_info_vtd {
  */
 struct iommu_hw_info_arm_smmuv3 {
 	__u32 flags;
-	__u32 __reserved;
+	__u32 impl;
 	__u32 idr[6];
 	__u32 iidr;
 	__u32 aidr;
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
index a8a78131702d..63861c60b615 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
@@ -10,7 +10,9 @@
 void *arm_smmu_hw_info(struct device *dev, u32 *length, u32 *type)
 {
 	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
+	struct arm_smmu_device *smmu = master->smmu;
 	struct iommu_hw_info_arm_smmuv3 *info;
+	u32 flags = 0, impl = 0;
 	u32 __iomem *base_idr;
 	unsigned int i;
 
@@ -18,15 +20,23 @@ void *arm_smmu_hw_info(struct device *dev, u32 *length, u32 *type)
 	if (!info)
 		return ERR_PTR(-ENOMEM);
 
-	base_idr = master->smmu->base + ARM_SMMU_IDR0;
+	base_idr = smmu->base + ARM_SMMU_IDR0;
 	for (i = 0; i <= 5; i++)
 		info->idr[i] = readl_relaxed(base_idr + i);
-	info->iidr = readl_relaxed(master->smmu->base + ARM_SMMU_IIDR);
-	info->aidr = readl_relaxed(master->smmu->base + ARM_SMMU_AIDR);
+	info->iidr = readl_relaxed(smmu->base + ARM_SMMU_IIDR);
+	info->aidr = readl_relaxed(smmu->base + ARM_SMMU_AIDR);
 
 	*length = sizeof(*info);
 	*type = IOMMU_HW_INFO_TYPE_ARM_SMMUV3;
 
+	if (smmu->impl_ops && smmu->impl_ops->hw_info) {
+		flags = smmu->impl_ops->hw_info(smmu, &impl);
+		if (flags) {
+			info->impl = impl;
+			info->flags |= flags;
+		}
+	}
+
 	return info;
 }
 
-- 
2.43.0