iommu/s390: Add support for iommu_device handling

Add support for the iommu_device_register interface to make
the s390 hardware iommus visible to the iommu core and in
sysfs.

Acked-by: Sebastian Ott <[e-mail]>
Signed-off-by: Joerg Roedel <[e-mail]>

arch/s390/include/asm/pci.h

···
 
 #include <linux/pci.h>
 #include <linux/mutex.h>
+#include <linux/iommu.h>
 #include <asm-generic/pci.h>
 #include <asm/pci_clp.h>
 #include <asm/pci_debug.h>
···
 	unsigned long	iommu_pages;
 	unsigned int	next_bit;
 
+	struct iommu_device iommu_dev;  /* IOMMU core handle */
+
 	char res_name[16];
 	struct zpci_bar_struct bars[PCI_BAR_COUNT];
 
···
 int clp_enable_fh(struct zpci_dev *, u8);
 int clp_disable_fh(struct zpci_dev *);
 int clp_get_state(u32 fid, enum zpci_state *state);
+
+/* IOMMU Interface */
+int zpci_init_iommu(struct zpci_dev *zdev);
+void zpci_destroy_iommu(struct zpci_dev *zdev);
 
 #ifdef CONFIG_PCI
 /* Error handling and recovery */

arch/s390/pci/pci.c

···
 
 	zpci_exit_slot(zdev);
 	zpci_cleanup_bus_resources(zdev);
+	zpci_destroy_iommu(zdev);
 	zpci_free_domain(zdev);
 
 	spin_lock(&zpci_list_lock);
···
 	if (rc)
 		goto out;
 
+	rc = zpci_init_iommu(zdev);
+	if (rc)
+		goto out_free;
+
 	mutex_init(&zdev->lock);
 	if (zdev->state == ZPCI_FN_STATE_CONFIGURED) {
 		rc = zpci_enable_device(zdev);
 		if (rc)
-			goto out_free;
+			goto out_destroy_iommu;
 	}
 	rc = zpci_scan_bus(zdev);
 	if (rc)
···
 out_disable:
 	if (zdev->state == ZPCI_FN_STATE_ONLINE)
 		zpci_disable_device(zdev);
+out_destroy_iommu:
+	zpci_destroy_iommu(zdev);
 out_free:
 	zpci_free_domain(zdev);
 out:

drivers/iommu/s390-iommu.c

···
  */
 #define S390_IOMMU_PGSIZES	(~0xFFFUL)
 
+static struct iommu_ops s390_iommu_ops;
+
 struct s390_domain {
 	struct iommu_domain	domain;
 	struct list_head	devices;
···
 static int s390_iommu_add_device(struct device *dev)
 {
 	struct iommu_group *group = iommu_group_get_for_dev(dev);
+	struct zpci_dev *zdev = to_pci_dev(dev)->sysdata;
 
 	if (IS_ERR(group))
 		return PTR_ERR(group);
 
 	iommu_group_put(group);
+	iommu_device_link(&zdev->iommu_dev, dev);
 
 	return 0;
 }
···
 			s390_iommu_detach_device(domain, dev);
 	}
 
+	iommu_device_unlink(&zdev->iommu_dev, dev);
 	iommu_group_remove_device(dev);
 }
 
···
 		return 0;
 
 	return size;
+}
+
+int zpci_init_iommu(struct zpci_dev *zdev)
+{
+	int rc = 0;
+
+	rc = iommu_device_sysfs_add(&zdev->iommu_dev, NULL, NULL,
+				    "s390-iommu.%08x", zdev->fid);
+	if (rc)
+		goto out_err;
+
+	iommu_device_set_ops(&zdev->iommu_dev, &s390_iommu_ops);
+
+	rc = iommu_device_register(&zdev->iommu_dev);
+	if (rc)
+		goto out_sysfs;
+
+	return 0;
+
+out_sysfs:
+	iommu_device_sysfs_remove(&zdev->iommu_dev);
+
+out_err:
+	return rc;
+}
+
+void zpci_destroy_iommu(struct zpci_dev *zdev)
+{
+	iommu_device_unregister(&zdev->iommu_dev);
+	iommu_device_sysfs_remove(&zdev->iommu_dev);
 }
 
 static struct iommu_ops s390_iommu_ops = {