Merge tag 'iommu-updates-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:

 - Allow compiling the ARM-SMMU drivers as modules.

 - Fixes and cleanups for the ARM-SMMU drivers and io-pgtable code
   collected by Will Deacon. The merge-commit (6855d1ba7537) has all the
   details.

 - Cleanup of the iommu_put_resv_regions() call-backs in various
   drivers.

 - AMD IOMMU driver cleanups.

 - Update for the x2APIC support in the AMD IOMMU driver.

 - Preparation patches for Intel VT-d nested mode support.

 - RMRR and identity domain handling fixes for the Intel VT-d driver.

 - More small fixes and cleanups.

* tag 'iommu-updates-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (87 commits)
  iommu/amd: Remove the unnecessary assignment
  iommu/vt-d: Remove unnecessary WARN_ON_ONCE()
  iommu/vt-d: Unnecessary to handle default identity domain
  iommu/vt-d: Allow devices with RMRRs to use identity domain
  iommu/vt-d: Add RMRR base and end addresses sanity check
  iommu/vt-d: Mark firmware tainted if RMRR fails sanity check
  iommu/amd: Remove unused struct member
  iommu/amd: Replace two consecutive readl calls with one readq
  iommu/vt-d: Don't reject Host Bridge due to scope mismatch
  PCI/ATS: Add PASID stubs
  iommu/arm-smmu-v3: Return -EBUSY when trying to re-add a device
  iommu/arm-smmu-v3: Improve add_device() error handling
  iommu/arm-smmu-v3: Use WRITE_ONCE() when changing validity of an STE
  iommu/arm-smmu-v3: Add second level of context descriptor table
  iommu/arm-smmu-v3: Prepare for handling arm_smmu_write_ctx_desc() failure
  iommu/arm-smmu-v3: Propagate ssid_bits
  iommu/arm-smmu-v3: Add support for Substream IDs
  iommu/arm-smmu-v3: Add context descriptor tables allocators
  iommu/arm-smmu-v3: Prepare arm_smmu_s1_cfg for SSID support
  ACPI/IORT: Parse SSID property of named component node
  ...

1 files changed, 49 insertions, 2 deletions

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3ead597e1c57..3e3528436e0b 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -22,6 +22,7 @@
 #include <linux/bitops.h>
 #include <linux/property.h>
 #include <linux/fsl/mc.h>
+#include <linux/module.h>
 #include <trace/events/iommu.h>
 
 static struct kset *iommu_group_kset;
@@ -141,6 +142,7 @@ int iommu_device_register(struct iommu_device *iommu)
 	spin_unlock(&iommu_device_lock);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(iommu_device_register);
 
 void iommu_device_unregister(struct iommu_device *iommu)
 {
@@ -148,6 +150,7 @@ void iommu_device_unregister(struct iommu_device *iommu)
 	list_del(&iommu->list);
 	spin_unlock(&iommu_device_lock);
 }
+EXPORT_SYMBOL_GPL(iommu_device_unregister);
 
 static struct iommu_param *iommu_get_dev_param(struct device *dev)
 {
@@ -183,10 +186,21 @@ int iommu_probe_device(struct device *dev)
 	if (!iommu_get_dev_param(dev))
 		return -ENOMEM;
 
+	if (!try_module_get(ops->owner)) {
+		ret = -EINVAL;
+		goto err_free_dev_param;
+	}
+
 	ret = ops->add_device(dev);
 	if (ret)
-		iommu_free_dev_param(dev);
+		goto err_module_put;
+
+	return 0;
 
+err_module_put:
+	module_put(ops->owner);
+err_free_dev_param:
+	iommu_free_dev_param(dev);
 	return ret;
 }
 
@@ -197,7 +211,10 @@ void iommu_release_device(struct device *dev)
 	if (dev->iommu_group)
 		ops->remove_device(dev);
 
-	iommu_free_dev_param(dev);
+	if (dev->iommu_param) {
+		module_put(ops->owner);
+		iommu_free_dev_param(dev);
+	}
 }
 
 static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
@@ -887,6 +904,7 @@ struct iommu_group *iommu_group_ref_get(struct iommu_group *group)
 	kobject_get(group->devices_kobj);
 	return group;
 }
+EXPORT_SYMBOL_GPL(iommu_group_ref_get);
 
 /**
  * iommu_group_put - Decrement group reference
@@ -1260,6 +1278,7 @@ struct iommu_group *generic_device_group(struct device *dev)
 {
 	return iommu_group_alloc();
 }
+EXPORT_SYMBOL_GPL(generic_device_group);
 
 /*
  * Use standard PCI bus topology, isolation features, and DMA alias quirks
@@ -1327,6 +1346,7 @@ struct iommu_group *pci_device_group(struct device *dev)
 	/* No shared group found, allocate new */
 	return iommu_group_alloc();
 }
+EXPORT_SYMBOL_GPL(pci_device_group);
 
 /* Get the IOMMU group for device on fsl-mc bus */
 struct iommu_group *fsl_mc_device_group(struct device *dev)
@@ -1339,6 +1359,7 @@ struct iommu_group *fsl_mc_device_group(struct device *dev)
 		group = iommu_group_alloc();
 	return group;
 }
+EXPORT_SYMBOL_GPL(fsl_mc_device_group);
 
 /**
  * iommu_group_get_for_dev - Find or create the IOMMU group for a device
@@ -1407,6 +1428,7 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
 
 	return group;
 }
+EXPORT_SYMBOL(iommu_group_get_for_dev);
 
 struct iommu_domain *iommu_group_default_domain(struct iommu_group *group)
 {
@@ -1537,6 +1559,11 @@ int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops)
 {
 	int err;
 
+	if (ops == NULL) {
+		bus->iommu_ops = NULL;
+		return 0;
+	}
+
 	if (bus->iommu_ops != NULL)
 		return -EBUSY;
 
@@ -2230,6 +2257,25 @@ void iommu_put_resv_regions(struct device *dev, struct list_head *list)
 		ops->put_resv_regions(dev, list);
 }
 
+/**
+ * generic_iommu_put_resv_regions - Reserved region driver helper
+ * @dev: device for which to free reserved regions
+ * @list: reserved region list for device
+ *
+ * IOMMU drivers can use this to implement their .put_resv_regions() callback
+ * for simple reservations. Memory allocated for each reserved region will be
+ * freed. If an IOMMU driver allocates additional resources per region, it is
+ * going to have to implement a custom callback.
+ */
+void generic_iommu_put_resv_regions(struct device *dev, struct list_head *list)
+{
+	struct iommu_resv_region *entry, *next;
+
+	list_for_each_entry_safe(entry, next, list, list)
+		kfree(entry);
+}
+EXPORT_SYMBOL(generic_iommu_put_resv_regions);
+
 struct iommu_resv_region *iommu_alloc_resv_region(phys_addr_t start,
 						  size_t length, int prot,
 						  enum iommu_resv_type type)
@@ -2247,6 +2293,7 @@ struct iommu_resv_region *iommu_alloc_resv_region(phys_addr_t start,
 	region->type = type;
 	return region;
 }
+EXPORT_SYMBOL_GPL(iommu_alloc_resv_region);
 
 static int
 request_default_domain_for_dev(struct device *dev, unsigned long type)