Commit 17de3f5f authored by Robin Murphy's avatar Robin Murphy Committed by Joerg Roedel
Browse files

iommu: Retire bus ops 



With the rest of the API internals converted, it's time to finally
tackle probe_device and how we bootstrap the per-device ops association
to begin with. This ends up being disappointingly straightforward, since
fwspec users are already doing it in order to find their of_xlate
callback, and it works out that we can easily do the equivalent for
other drivers too. Then shuffle the remaining awareness of iommu_ops
into the couple of core headers that still need it, and breathe a sigh
of relief.

Ding dong the bus ops are gone!

CC: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/a59011ef65b4b6657cb0b7a388d786b779b61305.1700589539.git.robin.murphy@arm.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 01bf81af

drivers/iommu/iommu.c

+18 −13
Original line number Diff line number Diff line
@@ -148,7 +148,7 @@ struct iommu_group_attribute iommu_group_attr_##_name = \ 
static LIST_HEAD(iommu_device_list);

static DEFINE_SPINLOCK(iommu_device_lock);



static struct bus_type * const iommu_buses[] = {

static const struct bus_type * const iommu_buses[] = {

	&platform_bus_type,

#ifdef CONFIG_PCI

	&pci_bus_type,
@@ -257,13 +257,6 @@ int iommu_device_register(struct iommu_device *iommu, 
	/* We need to be able to take module references appropriately */

	if (WARN_ON(is_module_address((unsigned long)ops) && !ops->owner))

		return -EINVAL;

	/*

	 * Temporarily enforce global restriction to a single driver. This was

	 * already the de-facto behaviour, since any possible combination of

	 * existing drivers would compete for at least the PCI or platform bus.

	 */

	if (iommu_buses[0]->iommu_ops && iommu_buses[0]->iommu_ops != ops)

		return -EBUSY;



	iommu->ops = ops;

	if (hwdev)
@@ -273,10 +266,8 @@ int iommu_device_register(struct iommu_device *iommu, 
	list_add_tail(&iommu->list, &iommu_device_list);

	spin_unlock(&iommu_device_lock);



	for (int i = 0; i < ARRAY_SIZE(iommu_buses) && !err; i++) {

		iommu_buses[i]->iommu_ops = ops;

	for (int i = 0; i < ARRAY_SIZE(iommu_buses) && !err; i++)

		err = bus_iommu_probe(iommu_buses[i]);

	}

	if (err)

		iommu_device_unregister(iommu);

	return err;
@@ -329,7 +320,6 @@ int iommu_device_register_bus(struct iommu_device *iommu, 
	list_add_tail(&iommu->list, &iommu_device_list);

	spin_unlock(&iommu_device_lock);



	bus->iommu_ops = ops;

	err = bus_iommu_probe(bus);

	if (err) {

		iommu_device_unregister_bus(iommu, bus, nb);
@@ -496,12 +486,27 @@ static void iommu_deinit_device(struct device *dev) 


static int __iommu_probe_device(struct device *dev, struct list_head *group_list)

{

	const struct iommu_ops *ops = dev->bus->iommu_ops;

	const struct iommu_ops *ops;

	struct iommu_fwspec *fwspec;

	struct iommu_group *group;

	static DEFINE_MUTEX(iommu_probe_device_lock);

	struct group_device *gdev;

	int ret;



	/*

	 * For FDT-based systems and ACPI IORT/VIOT, drivers register IOMMU

	 * instances with non-NULL fwnodes, and client devices should have been

	 * identified with a fwspec by this point. Otherwise, we can currently

	 * assume that only one of Intel, AMD, s390, PAMU or legacy SMMUv2 can

	 * be present, and that any of their registered instances has suitable

	 * ops for probing, and thus cheekily co-opt the same mechanism.

	 */

	fwspec = dev_iommu_fwspec_get(dev);

	if (fwspec && fwspec->ops)

		ops = fwspec->ops;

	else

		ops = iommu_ops_from_fwnode(NULL);



	if (!ops)

		return -ENODEV;

	/*

include/acpi/acpi_bus.h

+2 −0
Original line number Diff line number Diff line
@@ -627,6 +627,8 @@ struct acpi_pci_root { 


/* helper */



struct iommu_ops;



bool acpi_dma_supported(const struct acpi_device *adev);

enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev);

int acpi_iommu_fwspec_init(struct device *dev, u32 id,

include/linux/device.h

+0 −1
Original line number Diff line number Diff line
@@ -42,7 +42,6 @@ struct class; 
struct subsys_private;

struct device_node;

struct fwnode_handle;

struct iommu_ops;

struct iommu_group;

struct dev_pin_info;

struct dev_iommu;

include/linux/device/bus.h

+0 −5
Original line number Diff line number Diff line
@@ -62,9 +62,6 @@ struct fwnode_handle; 
 *			this bus.

 * @pm:		Power management operations of this bus, callback the specific

 *		device driver's pm-ops.

 * @iommu_ops:  IOMMU specific operations for this bus, used to attach IOMMU

 *              driver implementations to a bus and allow the driver to do

 *              bus-specific setup

 * @need_parent_lock:	When probing or removing a device on this bus, the

 *			device core should lock the device's parent.

 *
@@ -104,8 +101,6 @@ struct bus_type { 


	const struct dev_pm_ops *pm;



	const struct iommu_ops *iommu_ops;



	bool need_parent_lock;

};

include/linux/dma-map-ops.h

+1 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/slab.h>



struct cma;

struct iommu_ops;



/*

 * Values for struct dma_map_ops.flags: