ANDROID: KVM: arm64: iommu: Run validate() on struct pkvm_iommu

In preparation for needing to validate more aspects of a device that is
about to be registered, change the callback to accept the to-be-added
'struct pkvm_iommu' rather than individual inputs.

Bug: 190463801
Signed-off-by: David Brazdil <dbrazdil@google.com>
Change-Id: I3fb911e4280c220ddd779cf6a5fc9c302a5617f7

arch/arm64/kvm/hyp/include/nvhe/iommu.h

@@ -20,10 +20,11 @@ struct pkvm_iommu_ops {
 	int (*init)(void *data, size_t size);
 
 	/*
-	 * Driver-specific validation of device registration inputs.
-	 * This should be stateless. No locks are held at entry.
+	 * Driver-specific validation of a device that is being registered.
+	 * All fields of the device struct have been populated.
+	 * Called with the host lock held.
 	 */
-	int (*validate)(phys_addr_t base, size_t size);
+	int (*validate)(struct pkvm_iommu *dev);
 
 	/*
 	 * Callback to apply a host stage-2 mapping change at driver level.

arch/arm64/kvm/hyp/nvhe/iommu.c

@@ -306,12 +306,6 @@ int __pkvm_iommu_register(unsigned long dev_id,
 	if (!is_mmio_range(dev_pa, dev_size))
 		return -EINVAL;
 
-	if (drv->ops->validate) {
-		ret = drv->ops->validate(dev_pa, dev_size);
-		if (ret)
-			return ret;
-	}
-
 	/*
 	 * Accept memory donation if the host is providing new memory.
 	 * Note: We do not return the memory even if there is an error later.
@@ -350,6 +344,12 @@ int __pkvm_iommu_register(unsigned long dev_id,
 		goto out;
 	}
 
+	if (dev->ops->validate) {
+		ret = dev->ops->validate(dev);
+		if (ret)
+			goto out;
+	}
+
 	/*
 	 * Unmap the device's MMIO range from host stage-2. If registration
 	 * is successful, future attempts to re-map will be blocked by

arch/arm64/kvm/hyp/nvhe/iommu/s2mpu.c

@@ -465,9 +465,9 @@ static int s2mpu_init(void *data, size_t size)
 	return ret;
 }
 
-static int s2mpu_validate(phys_addr_t pa, size_t size)
+static int s2mpu_validate(struct pkvm_iommu *dev)
 {
-	if (size != S2MPU_MMIO_SIZE)
+	if (dev->size != S2MPU_MMIO_SIZE)
 		return -EINVAL;
 
 	return 0;