[PATCH v5 0/7] Support attaching PASID to the blocked_domain

[PATCH v5 0/7] Support attaching PASID to the blocked_domain

[Yi Liu]

During the review of iommufd pasid series, Kevin and Jason suggested
attaching PASID to the blocked domain hence replacing the usage of
remove_dev_pasid() op [1]. This makes sense as it makes the PASID path
aligned with the RID path which attaches the RID to the blocked_domain
when it is to be blocked. To do it, it requires passing the old domain
to the iommu driver. This has been done in [2].

This series makes the Intel iommu driver, ARM SMMUv3 driver and AMD iommu
driver support attaching PASID to the blocked domain. And in the end remove
the remove_dev_pasid op from iommu_ops.

[1] https://lore.kernel.org/linux-iommu/20240816130202.GB2032816@nvidia.com/
[2] https://lore.kernel.org/linux-iommu/20241108021406.173972-1-baolu.lu@linux.intel.com/

v5:
 - Fix an issue spotted by Baolu in patch 01 of v4. The new version lifts the
   group check to be the first check, hence it can ensure a valid iommu_ops
   returned by dev_iommu_ops(). Per this changes, it also removes the
   dev_has_iommu() check as it is duplicated with the group check. Due to the
   changes, drop the r-b tags on this patch.
 - Add Baolu's r-b tag.

v4: https://lore.kernel.org/linux-iommu/20241108120427.13562-1-yi.l.liu@intel.com/
 - Remove unnecessary braces in patch 02 (Vasant)
 - Minor tweaks to patch 01 and 03 (Kevin)
 - Add r-b tags from Jason, Vasant, Kevin

v3: https://lore.kernel.org/linux-iommu/20241104132033.14027-1-yi.l.liu@intel.com/
 - Add a patch to check remove_dev_pasid() in iommu_attach_device_pasid()
 - Split patch 01 of v2 into two patches, drop the r-b of this patch due the
   split.
 - Add AMD iommu blocked domain pasid support (Jason)
 - Remove the remove_dev_pasid op as all the iommu drivers that support pasid
   attach have supported attaching pasid to blocked domain.

v2: https://lore.kernel.org/linux-iommu/20241018055824.24880-1-yi.l.liu@intel.com/#t
 - Add Kevin's r-b
 - Adjust the order of patch 03 of v1, it should be the first patch (Baolu)

v1: https://lore.kernel.org/linux-iommu/20240912130653.11028-1-yi.l.liu@intel.com/

Regards,
	Yi Liu

Jason Gunthorpe (1):
  iommu/arm-smmu-v3: Make the blocked domain support PASID

Yi Liu (6):
  iommu: Prevent pasid attach if no ops->remove_dev_pasid
  iommu: Consolidate the ops->remove_dev_pasid usage into a helper
  iommu: Detaching pasid by attaching to the blocked_domain
  iommu/vt-d: Make the blocked domain support PASID
  iommu/amd: Make the blocked domain support PASID
  iommu: Remove the remove_dev_pasid op

 drivers/iommu/amd/iommu.c                   | 10 +++++-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 12 +++----
 drivers/iommu/intel/iommu.c                 | 15 ++++++---
 drivers/iommu/iommu.c                       | 35 +++++++++++++--------
 include/linux/iommu.h                       |  5 ---
 5 files changed, 48 insertions(+), 29 deletions(-)

-- 
2.34.1

[PATCH v5 1/7] iommu: Prevent pasid attach if no ops->remove_dev_pasid

[Yi Liu]

driver should implement both set_dev_pasid and remove_dev_pasid op, otherwise
it is a problem how to detach pasid. In reality, it is impossible that an
iommu driver implements set_dev_pasid() but no remove_dev_pasid() op. However,
it is better to check it.

Move the group check to be the first as dev_iommu_ops() may fail when there
is no valid group. Also take the chance to remove the dev_has_iommu() check
as it is duplicated to the group check.

Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/iommu.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 13fcd9d8f2df..b743fe612441 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -3354,16 +3354,19 @@ int iommu_attach_device_pasid(struct iommu_domain *domain,
 	/* Caller must be a probed driver on dev */
 	struct iommu_group *group = dev->iommu_group;
 	struct group_device *device;
+	const struct iommu_ops *ops;
 	int ret;
 
-	if (!domain->ops->set_dev_pasid)
-		return -EOPNOTSUPP;
-
 	if (!group)
 		return -ENODEV;
 
-	if (!dev_has_iommu(dev) || dev_iommu_ops(dev) != domain->owner ||
-	    pasid == IOMMU_NO_PASID)
+	ops = dev_iommu_ops(dev);
+
+	if (!domain->ops->set_dev_pasid ||
+	    !ops->remove_dev_pasid)
+		return -EOPNOTSUPP;
+
+	if (ops != domain->owner || pasid == IOMMU_NO_PASID)
 		return -EINVAL;
 
 	mutex_lock(&group->mutex);
-- 
2.34.1

Re: [PATCH v5 1/7] iommu: Prevent pasid attach if no ops->remove_dev_pasid

[Jason Gunthorpe]

On Wed, Nov 13, 2024 at 05:46:07AM -0800, Yi Liu wrote:
> driver should implement both set_dev_pasid and remove_dev_pasid op, otherwise
> it is a problem how to detach pasid. In reality, it is impossible that an
> iommu driver implements set_dev_pasid() but no remove_dev_pasid() op. However,
> it is better to check it.
> 
> Move the group check to be the first as dev_iommu_ops() may fail when there
> is no valid group. Also take the chance to remove the dev_has_iommu() check
> as it is duplicated to the group check.
> 
> Signed-off-by: Yi Liu <yi.l.liu@intel.com>
> ---
>  drivers/iommu/iommu.c | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

Jason

[PATCH v5 2/7] iommu: Consolidate the ops->remove_dev_pasid usage into a helper

[Yi Liu]

Add a wrapper for the ops->remove_dev_pasid, this consolidates the iommu_ops
fetching and callback invoking. It is also a preparation for starting the
transition from using remove_dev_pasid op to detach pasid to the way using
blocked_domain to detach pasid.

Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/iommu.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index b743fe612441..c1ab42ff5c4b 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -3298,6 +3298,14 @@ bool iommu_group_dma_owner_claimed(struct iommu_group *group)
 }
 EXPORT_SYMBOL_GPL(iommu_group_dma_owner_claimed);
 
+static void iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
+				   struct iommu_domain *domain)
+{
+	const struct iommu_ops *ops = dev_iommu_ops(dev);
+
+	ops->remove_dev_pasid(dev, pasid, domain);
+}
+
 static int __iommu_set_group_pasid(struct iommu_domain *domain,
 				   struct iommu_group *group, ioasid_t pasid)
 {
@@ -3316,11 +3324,9 @@ static int __iommu_set_group_pasid(struct iommu_domain *domain,
 err_revert:
 	last_gdev = device;
 	for_each_group_device(group, device) {
-		const struct iommu_ops *ops = dev_iommu_ops(device->dev);
-
 		if (device == last_gdev)
 			break;
-		ops->remove_dev_pasid(device->dev, pasid, domain);
+		iommu_remove_dev_pasid(device->dev, pasid, domain);
 	}
 	return ret;
 }
@@ -3330,12 +3336,9 @@ static void __iommu_remove_group_pasid(struct iommu_group *group,
 				       struct iommu_domain *domain)
 {
 	struct group_device *device;
-	const struct iommu_ops *ops;
 
-	for_each_group_device(group, device) {
-		ops = dev_iommu_ops(device->dev);
-		ops->remove_dev_pasid(device->dev, pasid, domain);
-	}
+	for_each_group_device(group, device)
+		iommu_remove_dev_pasid(device->dev, pasid, domain);
 }
 
 /*
-- 
2.34.1

[PATCH v5 3/7] iommu: Detaching pasid by attaching to the blocked_domain

[Yi Liu]

The iommu drivers are on the way to detach pasid by attaching to the blocked
domain. However, this cannot be done in one shot. During the transition, iommu
core would select between the remove_dev_pasid op and the blocked domain.

Suggested-by: Kevin Tian <kevin.tian@intel.com>
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/iommu.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index c1ab42ff5c4b..25d170de76fe 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -3302,8 +3302,18 @@ static void iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
 				   struct iommu_domain *domain)
 {
 	const struct iommu_ops *ops = dev_iommu_ops(dev);
+	struct iommu_domain *blocked_domain = ops->blocked_domain;
+	int ret = 1;
 
-	ops->remove_dev_pasid(dev, pasid, domain);
+	if (blocked_domain && blocked_domain->ops->set_dev_pasid) {
+		ret = blocked_domain->ops->set_dev_pasid(blocked_domain,
+							 dev, pasid, domain);
+	} else {
+		ops->remove_dev_pasid(dev, pasid, domain);
+		ret = 0;
+	}
+
+	WARN_ON(ret);
 }
 
 static int __iommu_set_group_pasid(struct iommu_domain *domain,
@@ -3366,7 +3376,9 @@ int iommu_attach_device_pasid(struct iommu_domain *domain,
 	ops = dev_iommu_ops(dev);
 
 	if (!domain->ops->set_dev_pasid ||
-	    !ops->remove_dev_pasid)
+	    (!ops->remove_dev_pasid &&
+	     (!ops->blocked_domain ||
+	      !ops->blocked_domain->ops->set_dev_pasid)))
 		return -EOPNOTSUPP;
 
 	if (ops != domain->owner || pasid == IOMMU_NO_PASID)
-- 
2.34.1

[PATCH v5 4/7] iommu/arm-smmu-v3: Make the blocked domain support PASID

[Yi Liu]

From: Jason Gunthorpe <jgg@nvidia.com>

The blocked domain is used to park RID to be blocking DMA state. This
can be extended to PASID as well. By this, the remove_dev_pasid() op
of ARM SMMUv3 can be dropped.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 7ee3cbbe3744..276738d047e7 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2979,13 +2979,12 @@ int arm_smmu_set_pasid(struct arm_smmu_master *master,
 	return ret;
 }
 
-static void arm_smmu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
-				      struct iommu_domain *domain)
+static int arm_smmu_blocking_set_dev_pasid(struct iommu_domain *new_domain,
+					   struct device *dev, ioasid_t pasid,
+					   struct iommu_domain *old_domain)
 {
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(old_domain);
 	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
-	struct arm_smmu_domain *smmu_domain;
-
-	smmu_domain = to_smmu_domain(domain);
 
 	mutex_lock(&arm_smmu_asid_lock);
 	arm_smmu_clear_cd(master, pasid);
@@ -3006,6 +3005,7 @@ static void arm_smmu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
 		    sid_domain->type == IOMMU_DOMAIN_BLOCKED)
 			sid_domain->ops->attach_dev(sid_domain, dev);
 	}
+	return 0;
 }
 
 static void arm_smmu_attach_dev_ste(struct iommu_domain *domain,
@@ -3087,6 +3087,7 @@ static int arm_smmu_attach_dev_blocked(struct iommu_domain *domain,
 
 static const struct iommu_domain_ops arm_smmu_blocked_ops = {
 	.attach_dev = arm_smmu_attach_dev_blocked,
+	.set_dev_pasid = arm_smmu_blocking_set_dev_pasid,
 };
 
 static struct iommu_domain arm_smmu_blocked_domain = {
@@ -3514,7 +3515,6 @@ static struct iommu_ops arm_smmu_ops = {
 	.device_group		= arm_smmu_device_group,
 	.of_xlate		= arm_smmu_of_xlate,
 	.get_resv_regions	= arm_smmu_get_resv_regions,
-	.remove_dev_pasid	= arm_smmu_remove_dev_pasid,
 	.dev_enable_feat	= arm_smmu_dev_enable_feature,
 	.dev_disable_feat	= arm_smmu_dev_disable_feature,
 	.page_response		= arm_smmu_page_response,
-- 
2.34.1

[PATCH v5 5/7] iommu/vt-d: Make the blocked domain support PASID

[Yi Liu]

The blocked domain can be extended to park PASID of a device to be the
DMA blocking state. By this the remove_dev_pasid() op is dropped.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/intel/iommu.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 527f6f89d8a1..b08981bbd5ca 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -3248,10 +3248,15 @@ static int blocking_domain_attach_dev(struct iommu_domain *domain,
 	return 0;
 }
 
+static int blocking_domain_set_dev_pasid(struct iommu_domain *domain,
+					 struct device *dev, ioasid_t pasid,
+					 struct iommu_domain *old);
+
 static struct iommu_domain blocking_domain = {
 	.type = IOMMU_DOMAIN_BLOCKED,
 	.ops = &(const struct iommu_domain_ops) {
 		.attach_dev	= blocking_domain_attach_dev,
+		.set_dev_pasid	= blocking_domain_set_dev_pasid,
 	}
 };
 
@@ -4105,13 +4110,16 @@ void domain_remove_dev_pasid(struct iommu_domain *domain,
 	kfree(dev_pasid);
 }
 
-static void intel_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
-					 struct iommu_domain *domain)
+static int blocking_domain_set_dev_pasid(struct iommu_domain *domain,
+					 struct device *dev, ioasid_t pasid,
+					 struct iommu_domain *old)
 {
 	struct device_domain_info *info = dev_iommu_priv_get(dev);
 
 	intel_pasid_tear_down_entry(info->iommu, dev, pasid, false);
-	domain_remove_dev_pasid(domain, dev, pasid);
+	domain_remove_dev_pasid(old, dev, pasid);
+
+	return 0;
 }
 
 struct dev_pasid_info *
@@ -4483,7 +4491,6 @@ const struct iommu_ops intel_iommu_ops = {
 	.dev_disable_feat	= intel_iommu_dev_disable_feat,
 	.is_attach_deferred	= intel_iommu_is_attach_deferred,
 	.def_domain_type	= device_def_domain_type,
-	.remove_dev_pasid	= intel_iommu_remove_dev_pasid,
 	.pgsize_bitmap		= SZ_4K,
 	.page_response		= intel_iommu_page_response,
 	.default_domain_ops = &(const struct iommu_domain_ops) {
-- 
2.34.1

[PATCH v5 6/7] iommu/amd: Make the blocked domain support PASID

[Yi Liu]

The blocked domain can be extended to park PASID of a device to be the
DMA blocking state. By this the remove_dev_pasid() op is dropped.

Remove PASID from old domain and device GCR3 table. No need to attach
PASID to the blocked domain as clearing PASID from GCR3 table will make
sure all DMAs for that PASID are blocked.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/amd/iommu.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 5ce8e6504ba7..d216313b6d44 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2468,10 +2468,19 @@ static int blocked_domain_attach_device(struct iommu_domain *domain,
 	return 0;
 }
 
+static int blocked_domain_set_dev_pasid(struct iommu_domain *domain,
+					struct device *dev, ioasid_t pasid,
+					struct iommu_domain *old)
+{
+	amd_iommu_remove_dev_pasid(dev, pasid, old);
+	return 0;
+}
+
 static struct iommu_domain blocked_domain = {
 	.type = IOMMU_DOMAIN_BLOCKED,
 	.ops = &(const struct iommu_domain_ops) {
 		.attach_dev     = blocked_domain_attach_device,
+		.set_dev_pasid  = blocked_domain_set_dev_pasid,
 	}
 };
 
@@ -2894,7 +2903,6 @@ const struct iommu_ops amd_iommu_ops = {
 	.def_domain_type = amd_iommu_def_domain_type,
 	.dev_enable_feat = amd_iommu_dev_enable_feature,
 	.dev_disable_feat = amd_iommu_dev_disable_feature,
-	.remove_dev_pasid = amd_iommu_remove_dev_pasid,
 	.page_response = amd_iommu_page_response,
 	.default_domain_ops = &(const struct iommu_domain_ops) {
 		.attach_dev	= amd_iommu_attach_device,
-- 
2.34.1

[PATCH v5 7/7] iommu: Remove the remove_dev_pasid op

[Yi Liu]

The iommu drivers that supports PASID have supported attaching pasid to the
blocked_domain, hence remove the remove_dev_pasid op from the iommu_ops.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/iommu.c | 17 ++++-------------
 include/linux/iommu.h |  5 -----
 2 files changed, 4 insertions(+), 18 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 25d170de76fe..8a3e3a753fd5 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -3303,17 +3303,9 @@ static void iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
 {
 	const struct iommu_ops *ops = dev_iommu_ops(dev);
 	struct iommu_domain *blocked_domain = ops->blocked_domain;
-	int ret = 1;
 
-	if (blocked_domain && blocked_domain->ops->set_dev_pasid) {
-		ret = blocked_domain->ops->set_dev_pasid(blocked_domain,
-							 dev, pasid, domain);
-	} else {
-		ops->remove_dev_pasid(dev, pasid, domain);
-		ret = 0;
-	}
-
-	WARN_ON(ret);
+	WARN_ON(blocked_domain->ops->set_dev_pasid(blocked_domain,
+						   dev, pasid, domain));
 }
 
 static int __iommu_set_group_pasid(struct iommu_domain *domain,
@@ -3376,9 +3368,8 @@ int iommu_attach_device_pasid(struct iommu_domain *domain,
 	ops = dev_iommu_ops(dev);
 
 	if (!domain->ops->set_dev_pasid ||
-	    (!ops->remove_dev_pasid &&
-	     (!ops->blocked_domain ||
-	      !ops->blocked_domain->ops->set_dev_pasid)))
+	    !ops->blocked_domain ||
+	    !ops->blocked_domain->ops->set_dev_pasid)
 		return -EOPNOTSUPP;
 
 	if (ops != domain->owner || pasid == IOMMU_NO_PASID)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 0c3bfb66dc7c..1d033121bf00 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -537,9 +537,6 @@ static inline int __iommu_copy_struct_from_user_array(
  *		- IOMMU_DOMAIN_DMA: must use a dma domain
  *		- 0: use the default setting
  * @default_domain_ops: the default ops for domains
- * @remove_dev_pasid: Remove any translation configurations of a specific
- *                    pasid, so that any DMA transactions with this pasid
- *                    will be blocked by the hardware.
  * @pgsize_bitmap: bitmap of all possible supported page sizes
  * @owner: Driver module providing these ops
  * @identity_domain: An always available, always attachable identity
@@ -586,8 +583,6 @@ struct iommu_ops {
 			      struct iommu_page_response *msg);
 
 	int (*def_domain_type)(struct device *dev);
-	void (*remove_dev_pasid)(struct device *dev, ioasid_t pasid,
-				 struct iommu_domain *domain);
 
 	const struct iommu_domain_ops *default_domain_ops;
 	unsigned long pgsize_bitmap;
-- 
2.34.1