/*
* Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
* Author: Joerg Roedel <joerg.roedel@amd.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/bug.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/iommu.h>
#include <linux/idr.h>
#include <linux/notifier.h>
#include <linux/err.h>
#include <linux/pci.h>
#include <linux/bitops.h>
#include <trace/events/iommu.h>
static struct kset *iommu_group_kset;
static struct ida iommu_group_ida;
static struct mutex iommu_group_mutex;
struct iommu_callback_data {
const struct iommu_ops *ops;
};
struct iommu_group {
struct kobject kobj;
struct kobject *devices_kobj;
struct list_head devices;
struct mutex mutex;
struct blocking_notifier_head notifier;
void *iommu_data;
void (*iommu_data_release)(void *iommu_data);
char *name;
int id;
};
struct iommu_device {
struct list_head list;
struct device *dev;
char *name;
};
struct iommu_group_attribute {
struct attribute attr;
ssize_t (*show)(struct iommu_group *group, char *buf);
ssize_t (*store)(struct iommu_group *group,
const char *buf, size_t count);
};
#define IOMMU_GROUP_ATTR(_name, _mode, _show, _store) \
struct iommu_group_attribute iommu_group_attr_##_name = \
__ATTR(_name, _mode, _show, _store)
#define to_iommu_group_attr(_attr) \
container_of(_attr, struct iommu_group_attribute, attr)
#define to_iommu_group(_kobj) \
container_of(_kobj, struct iommu_group, kobj)
static ssize_t iommu_group_attr_show(struct kobject *kobj,
struct attribute *__attr, char *buf)
{
struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
struct iommu_group *group = to_iommu_group(kobj);
ssize_t ret = -EIO;
if (attr->show)
ret = attr->show(group, buf);
return ret;
}
static ssize_t iommu_group_attr_store(struct kobject *kobj,
struct attribute *__attr,
const char *buf, size_t count)
{
struct iommu_group_attribute *attr = to_iommu_group_attr(__attr);
struct iommu_group *group = to_iommu_group(kobj);
ssize_t ret = -EIO;
if (attr->store)
ret = attr->store(group, buf, count);
return ret;
}
static const struct sysfs_ops iommu_group_sysfs_ops = {
.show = iommu_group_attr_show,
.store = iommu_group_attr_store,
};
static int iommu_group_create_file(struct iommu_group *group,
struct iommu_group_attribute *attr)
{
return sysfs_create_file(&group->kobj, &attr->attr);
}
static void iommu_group_remove_file(struct iommu_group *group,
struct iommu_group_attribute *attr)
{
sysfs_remove_file(&group->kobj, &attr->attr);
}
static ssize_t iommu_group_show_name(struct iommu_group *group, char *buf)
{
return sprintf(buf, "%s\n", group->name);
}
static IOMMU_GROUP_ATTR(name, S_IRUGO, iommu_group_show_name, NULL);
static void iommu_group_release(struct kobject *kobj)
{
struct iommu_group *group = to_iommu_group(kobj);
if (group->iommu_data_release)
group->iommu_data_release(group->iommu_data);
mutex_lock(&iommu_group_mutex);
ida_remove(&iommu_group_ida, group->id);
mutex_unlock(&iommu_group_mutex);
kfree(group->name);
kfree(group);
}
static struct kobj_type iommu_group_ktype = {
.sysfs_ops = &iommu_group_sysfs_ops,
.release = iommu_group_release,
};
/**
* iommu_group_alloc - Allocate a new group
* @name: Optional name to associate with group, visible in sysfs
*
* This function is called by an iommu driver to allocate a new iommu
* group. The iommu group represents the minimum granularity of the iommu.
* Upon successful return, the caller holds a reference to the supplied
* group in order to hold the group until devices are added. Use
* iommu_group_put() to release this extra reference count, allowing the
* group to be automatically reclaimed once it has no devices or external
* references.
*/
struct iommu_group *iommu_group_alloc(void)
{
struct iommu_group *group;
int ret;
group = kzalloc(sizeof(*group), GFP_KERNEL);
if (!group)
return ERR_PTR(-ENOMEM);
group->kobj.kset = iommu_group_kset;
mutex_init(&group->mutex);
INIT_LIST_HEAD(&group->devices);
BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
mutex_lock(&iommu_group_mutex);
again:
if (unlikely(0 == ida_pre_get(&iommu_group_ida, GFP_KERNEL))) {
kfree(group);
mutex_unlock(&iommu_group_mutex);
return ERR_PTR(-ENOMEM);
}
if (-EAGAIN == ida_get_new(&iommu_group_ida, &group->id))
goto again;
mutex_unlock(&iommu_group_mutex);
ret = kobject_init_and_add(&group->kobj, &iommu_group_ktype,
NULL, "%d", group->id);
if (ret) {
mutex_lock(&iommu_group_mutex);
ida_remove(&iommu_group_ida, group->id);
mutex_unlock(&iommu_group_mutex);
kfree(group);
return ERR_PTR(ret);
}
group->devices_kobj = kobject_create_and_add("devices", &group->kobj);
if (!group->devices_kobj) {
kobject_put(&group->kobj); /* triggers .release & free */
return ERR_PTR(-ENOMEM);
}
/*
* The devices_kobj holds a reference on the group kobject, so
* as long as that exists so will the group. We can therefore
* use the devices_kobj for reference counting.
*/
kobject_put(&group->kobj);
return group;
}
EXPORT_SYMBOL_GPL(iommu_group_alloc);
struct iommu_group *iommu_group_get_by_id(int id)
{
struct kobject *group_kobj;
struct iommu_group *group;
const char *name;
if (!iommu_group_kset)
return NULL;
name = kasprintf(GFP_KERNEL, "%d", id);
if (!name)
return NULL;
group_kobj = kset_find_obj(iommu_group_kset, name);
kfree(name);
if (!group_kobj)
return NULL;
group = container_of(group_kobj, struct iommu_group, kobj);
BUG_ON(group->id != id);
kobject_get(group->devices_kobj);
kobject_put(&group->kobj);
return group;
}
EXPORT_SYMBOL_GPL(iommu_group_get_by_id);
/**
* iommu_group_get_iommudata - retrieve iommu_data registered for a group
* @group: the group
*
* iommu drivers can store data in the group for use when doing iommu
* operations. This function provides a way to retrieve it. Caller
* should hold a group reference.
*/
void *iommu_group_get_iommudata(struct iommu_group *group)
{
return group->iommu_data;
}
EXPORT_SYMBOL_GPL(iommu_group_get_iommudata);
/**
* iommu_group_set_iommudata - set iommu_data for a group
* @group: the group
* @iommu_data: new data
* @release: release function for iommu_data
*
* iommu drivers can store data in the group for use when doing iommu
* operations. This function provides a way to set the data after
* the group has been allocated. Caller should hold a group reference.
*/
void iommu_group_set_iommudata(struct iommu_group *group, void *iommu_data,
void (*release)(void *iommu_data))
{
group->iommu_data = iommu_data;
group->iommu_data_release = release;
}
EXPORT_SYMBOL_GPL(iommu_group_set_iommudata);
/**
* iommu_group_set_name - set name for a group
* @group: the group
* @name: name
*
* Allow iommu driver to set a name for a group. When set it will
* appear in a name attribute file under the group in sysfs.
*/
int iommu_group_set_name(struct iommu_group *group, const char *name)
{
int ret;
if (group->name) {
iommu_group_remove_file(group, &iommu_group_attr_name);
kfree(group->name);
group->name = NULL;
if (!name)
return 0;
}
group->name = kstrdup(name, GFP_KERNEL);
if (!group->name)
return -ENOMEM;
ret = iommu_group_create_file(group, &iommu_group_attr_name);
if (ret) {
kfree(group->name);
group->name = NULL;
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(iommu_group_set_name);
/**
* iommu_group_add_device - add a device to an iommu group
* @group: the group into which to add the device (reference should be held)
* @dev: the device
*
* This function is called by an iommu driver to add a device into a
* group. Adding a device increments the group reference count.
*/
int iommu_group_add_device(struct iommu_group *group, struct device *dev)
{
int ret, i = 0;
struct iommu_device *device;
device = kzalloc(sizeof(*device), GFP_KERNEL);
if (!device)
return -ENOMEM;
device->dev = dev;
ret = sysfs_create_link(&dev->kobj, &group->kobj, "iommu_group");
if (ret) {
kfree(device);
return ret;
}
device->name = kasprintf(GFP_KERNEL, "%s", kobject_name(&dev->kobj));
rename:
if (!device->name) {
sysfs_remove_link(&dev->kobj, "iommu_group");
kfree(device);
return -ENOMEM;
}
ret = sysfs_create_link_nowarn(group->devices_kobj,
&dev->kobj, device->name);
if (ret) {
kfree(device->name);
if (ret == -EEXIST && i >= 0) {
/*
* Account for the slim chance of collision
* and append an instance to the name.
*/
device->name = kasprintf(GFP_KERNEL, "%s.%d",
kobject_name(&dev->kobj), i++);
goto rename;
}
sysfs_remove_link(&dev->kobj, "iommu_group");
kfree(device);
return ret;
}
kobject_get(group->devices_kobj);
dev->iommu_group = group;
mutex_lock(&group->mutex);
list_add_tail(&device->list, &group->devices);
mutex_unlock(&group->mutex);
/* Notify any listeners about change to group. */
blocking_notifier_call_chain(&group->notifier,
IOMMU_GROUP_NOTIFY_ADD_DEVICE, dev);
trace_add_device_to_group(group->id, dev);
return 0;
}
EXPORT_SYMBOL_GPL(iommu_group_add_device);
/**
* iommu_group_remove_device - remove a device from it's current group
* @dev: device to be removed
*
* This function is called by an iommu driver to remove the device from
* it's current group. This decrements the iommu group reference count.
*/
void iommu_group_remove_device(struct device *dev)
{
struct iommu_group *group = dev->iommu_group;
struct iommu_device *tmp_device, *device = NULL;
/* Pre-notify listeners that a device is being removed. */
blocking_notifier_call_chain(&group->notifier,
IOMMU_GROUP_NOTIFY_DEL_DEVICE, dev);
mutex_lock(&group->mutex);
list_for_each_entry(tmp_device, &group->devices, list) {
if (tmp_device->dev == dev) {
device = tmp_device;
list_del(&device->list);
break;
}
}
mutex_unlock(&group->mutex);
if (!device)
return;
sysfs_remove_link(group->devices_kobj, device->name);
sysfs_remove_link(&dev->kobj, "iommu_group");
trace_remove_device_from_group(group->id, dev);
kfree(device->name);
kfree(device);
dev->iommu_group = NULL;
kobject_put(group->devices_kobj);
}
EXPORT_SYMBOL_GPL(iommu_group_remove_device);
/**
* iommu_group_for_each_dev - iterate over each device in the group
* @group: the group
* @data: caller opaque data to be passed to callback function
* @fn: caller supplied callback function
*
* This function is called by group users to iterate over group devices.
* Callers should hold a reference count to the group during callback.
* The group->mutex is held across callbacks, which will block calls to
* iommu_group_add/remove_device.
*/
int iommu_group_for_each_dev(struct iommu_group *group, void *data,
int (*fn)(struct device *, void *))
{
struct iommu_device *device;
int ret = 0;
mutex_lock(&group->mutex);
list_for_each_entry(device, &group->devices, list) {
ret = fn(device->dev, data);
if (ret)
break;
}
mutex_unlock(&group->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(iommu_group_for_each_dev);
/**
* iommu_group_get - Return the group for a device and increment reference
* @dev: get the group that this device belongs to
*
* This function is called by iommu drivers and users to get the group
* for the specified device. If found, the group is returned and the group
* reference in incremented, else NULL.
*/
struct iommu_group *iommu_group_get(struct device *dev)
{
struct iommu_group *group = dev->iommu_group;
if (group)
kobject_get(group->devices_kobj);
return group;
}
EXPORT_SYMBOL_GPL(iommu_group_get);
/**
* iommu_group_put - Decrement group reference
* @group: the group to use
*
* This function is called by iommu drivers and users to release the
* iommu group. Once the reference count is zero, the group is released.
*/
void iommu_group_put(struct iommu_group *group)
{
if (group)
kobject_put(group->devices_kobj);
}
EXPORT_SYMBOL_GPL(iommu_group_put);
/**
* iommu_group_register_notifier - Register a notifier for group changes
* @group: the group to watch
* @nb: notifier block to signal
*
* This function allows iommu group users to track changes in a group.
* See include/linux/iommu.h for actions sent via this notifier. Caller
* should hold a reference to the group throughout notifier registration.
*/
int iommu_group_register_notifier(struct iommu_group *group,
struct notifier_block *nb)
{
return blocking_notifier_chain_register(&group->notifier, nb);
}
EXPORT_SYMBOL_GPL(iommu_group_register_notifier);
/**
* iommu_group_unregister_notifier - Unregister a notifier
* @group: the group to watch
* @nb: notifier block to signal
*
* Unregister a previously registered group notifier block.
*/
int iommu_group_unregister_notifier(struct iommu_group *group,
struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&group->notifier, nb);
}
EXPORT_SYMBOL_GPL(iommu_group_unregister_notifier);
/**
* iommu_group_id - Return ID for a group
* @group: the group to ID
*
* Return the unique ID for the group matching the sysfs group number.
*/
int iommu_group_id(struct iommu_group *group)
{
return group->id;
}
EXPORT_SYMBOL_GPL(iommu_group_id);
static struct iommu_group *get_pci_alias_group(struct pci_dev *pdev,
unsigned long *devfns);
/*
* To consider a PCI device isolated, we require ACS to support Source
* Validation, Request Redirection, Completer Redirection, and Upstream
* Forwarding. This effectively means that devices cannot spoof their
* requester ID, requests and completions cannot be redirected, and all
* transactions are forwarded upstream, even as it passes through a
* bridge where the target device is downstream.
*/
#define REQ_ACS_FLAGS (PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF)
/*
* For multifunction devices which are not isolated from each other, find
* all the other non-isolated functions and look for existing groups. For
* each function, we also need to look for aliases to or from other devices
* that may already have a group.
*/
static struct iommu_group *get_pci_function_alias_group(struct pci_dev *pdev,
unsigned long *devfns)
{
struct pci_dev *tmp = NULL;
struct iommu_group *group;
if (!pdev->multifunction || pci_acs_enabled(pdev, REQ_ACS_FLAGS))
return NULL;
for_each_pci_dev(tmp) {
if (tmp == pdev || tmp->bus != pdev->bus ||
PCI_SLOT(tmp->devfn) != PCI_SLOT(pdev->devfn) ||
pci_acs_enabled(tmp, REQ_ACS_FLAGS))
continue;
group = get_pci_alias_group(tmp, devfns);
if (group) {
pci_dev_put(tmp);
return group;
}
}
return NULL;
}
/*
* Look for aliases to or from the given device for exisiting groups. The
* dma_alias_devfn only supports aliases on the same bus, therefore the search
* space is quite small (especially since we're really only looking at pcie
* device, and therefore only expect multiple slots on the root complex or
* downstream switch ports). It's conceivable though that a pair of
* multifunction devices could have aliases between them that would cause a
* loop. To prevent this, we use a bitmap to track where we've been.
*/
static struct iommu_group *get_pci_alias_group(struct pci_dev *pdev,
unsigned long *devfns)
{
struct pci_dev *tmp = NULL;
struct iommu_group *group;
if (test_and_set_bit(pdev->devfn & 0xff, devfns))
return NULL;
group = iommu_group_get(&pdev->dev);
if (group)
return group;
for_each_pci_dev(tmp) {
if (tmp == pdev || tmp->bus != pdev->bus)
continue;
/* We alias them or they alias us */
if (((pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN) &&
pdev->dma_alias_devfn == tmp->devfn) ||
((tmp->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN) &&
tmp->dma_alias_devfn == pdev->devfn)) {
group = get_pci_alias_group(tmp, devfns);
if (group) {
pci_dev_put(tmp);
return group;
}
group = get_pci_function_alias_group(tmp, devfns);
if (group) {
pci_dev_put(tmp);
return group;
}
}
}
return NULL;
}
struct group_for_pci_data {
struct pci_dev *pdev;
struct iommu_group *group;
};
/*
* DMA alias iterator callback, return the last seen device. Stop and return
* the IOMMU group if we find one along the way.
*/
static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
{
struct group_for_pci_data *data = opaque;
data->pdev = pdev;
data->group = iommu_group_get(&pdev->dev);
return data->group != NULL;
}
/*
* Use standard PCI bus topology, isolation features, and DMA alias quirks
* to find or create an IOMMU group for a device.
*/
static struct iommu_group *iommu_group_get_for_pci_dev(struct pci_dev *pdev)
{
struct group_for_pci_data data;
struct pci_bus *bus;
struct iommu_group *group = NULL;
u64 devfns[4] = { 0 };
/*
* Find the upstream DMA alias for the device. A device must not
* be aliased due to topology in order to have its own IOMMU group.
* If we find an alias along the way that already belongs to a
* group, use it.
*/
if (pci_for_each_dma_alias(pdev, get_pci_alias_or_group, &data))
return data.group;
pdev = data.pdev;
/*
* Continue upstream from the point of minimum IOMMU granularity
* due to aliases to the point where devices are protected from
* peer-to-peer DMA by PCI ACS. Again, if we find an existing
* group, use it.
*/
for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) {
if (!bus->self)
continue;
if (pci_acs_path_enabled(bus->self, NULL, REQ_ACS_FLAGS))
break;
pdev = bus->self;
group = iommu_group_get(&pdev->dev);
if (group)
return group;
}
/*
* Look for existing groups on device aliases. If we alias another
* device or another device aliases us, use the same group.
*/
group = get_pci_alias_group(pdev, (unsigned long *)devfns);
if (group)
return group;
/*
* Look for existing groups on non-isolated functions on the same
* slot and aliases of those funcions, if any. No need to clear
* the search bitmap, the tested devfns are still valid.
*/
group = get_pci_function_alias_group(pdev, (unsigned long *)devfns);
if (group)
return group;
/* No shared group found, allocate new */
return iommu_group_alloc();
}
/**
* iommu_group_get_for_dev - Find or create the IOMMU group for a device
* @dev: target device
*
* This function is intended to be called by IOMMU drivers and extended to
* support common, bus-defined algorithms when determining or creating the
* IOMMU group for a device. On success, the caller will hold a reference
* to the returned IOMMU group, which will already include the provided
* device. The reference should be released with iommu_group_put().
*/
struct iommu_group *iommu_group_get_for_dev(struct device *dev)
{
struct iommu_group *group;
int ret;
group = iommu_group_get(dev);
if (group)
return group;
if (!dev_is_pci(dev))
return ERR_PTR(-EINVAL);
group = iommu_group_get_for_pci_dev(to_pci_dev(dev));
if (IS_ERR(group))
return group;
ret = iommu_group_add_device(group, dev);
if (ret) {
iommu_group_put(group);
return ERR_PTR(ret);
}
return group;
}
static int add_iommu_group(struct device *dev, void *data)
{
struct iommu_callback_data *cb = data;
const struct iommu_ops *ops = cb->ops;
if (!ops->add_device)
return 0;
WARN_ON(dev->iommu_group);
ops->add_device(dev);
return 0;
}
static int iommu_bus_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
const struct iommu_ops *ops = dev->bus->iommu_ops;
struct iommu_group *group;
unsigned long group_action = 0;
/*
* ADD/DEL call into iommu driver ops if provided, which may
* result in ADD/DEL notifiers to group->notifier
*/
if (action == BUS_NOTIFY_ADD_DEVICE) {
if (ops->add_device)
return ops->add_device(dev);
} else if (action == BUS_NOTIFY_DEL_DEVICE) {
if (ops->remove_device && dev->iommu_group) {
ops->remove_device(dev);
return 0;
}
}
/*
* Remaining BUS_NOTIFYs get filtered and republished to the
* group, if anyone is listening
*/
group = iommu_group_get(dev);
if (!group)
return 0;
switch (action) {
case BUS_NOTIFY_BIND_DRIVER:
group_action = IOMMU_GROUP_NOTIFY_BIND_DRIVER;
break;
case BUS_NOTIFY_BOUND_DRIVER:
group_action = IOMMU_GROUP_NOTIFY_BOUND_DRIVER;
break;
case BUS_NOTIFY_UNBIND_DRIVER:
group_action = IOMMU_GROUP_NOTIFY_UNBIND_DRIVER;
break;
case BUS_NOTIFY_UNBOUND_DRIVER:
group_action = IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER;
break;
}
if (group_action)
blocking_notifier_call_chain(&group->notifier,
group_action, dev);
iommu_group_put(group);
return 0;
}
static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
{
int err;
struct notifier_block *nb;
struct iommu_callback_data cb = {
.ops = ops,
};
nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
if (!nb)
return -ENOMEM;
nb->notifier_call = iommu_bus_notifier;
err = bus_register_notifier(bus, nb);
if (err) {
kfree(nb);
return err;
}
err = bus_for_each_dev(bus, NULL, &cb, add_iommu_group);
if (err) {
bus_unregister_notifier(bus, nb);
kfree(nb);
return err;
}
return 0;
}
/**
* bus_set_iommu - set iommu-callbacks for the bus
* @bus: bus.
* @ops: the callbacks provided by the iommu-driver
*
* This function is called by an iommu driver to set the iommu methods
* used for a particular bus. Drivers for devices on that bus can use
* the iommu-api after these ops are registered.
* This special function is needed because IOMMUs are usually devices on
* the bus itself, so the iommu drivers are not initialized when the bus
* is set up. With this function the iommu-driver can set the iommu-ops
* afterwards.
*/
int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops)
{
int err;
if (bus->iommu_ops != NULL)
return -EBUSY;
bus->iommu_ops = ops;
/* Do IOMMU specific setup for this bus-type */
err = iommu_bus_init(bus, ops);
if (err)
bus->iommu_ops = NULL;
return err;
}
EXPORT_SYMBOL_GPL(bus_set_iommu);
bool iommu_present(struct bus_type *bus)
{
return bus->iommu_ops != NULL;
}
EXPORT_SYMBOL_GPL(iommu_present);
bool iommu_capable(struct bus_type *bus, enum iommu_cap cap)
{
if (!bus->iommu_ops || !bus->iommu_ops->capable)
return false;
return bus->iommu_ops->capable(cap);
}
EXPORT_SYMBOL_GPL(iommu_capable);
/**
* iommu_set_fault_handler() - set a fault handler for an iommu domain
* @domain: iommu domain
* @handler: fault handler
* @token: user data, will be passed back to the fault handler
*
* This function should be used by IOMMU users which want to be notified
* whenever an IOMMU fault happens.
*
* The fault handler itself should return 0 on success, and an appropriate
* error code otherwise.
*/
void iommu_set_fault_handler(struct iommu_domain *domain,
iommu_fault_handler_t handler,
void *token)
{
BUG_ON(!domain);
domain->handler = handler;
domain->handler_token = token;
}
EXPORT_SYMBOL_GPL(iommu_set_fault_handler);
struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
{
struct iommu_domain *domain;
int ret;
if (bus == NULL || bus->iommu_ops == NULL)
return NULL;
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!domain)
return NULL;
domain->ops = bus->iommu_ops;
ret = domain->ops->domain_init(domain);
if (ret)
goto out_free;
return domain;
out_free:
kfree(domain);
return NULL;
}
EXPORT_SYMBOL_GPL(iommu_domain_alloc);
void iommu_domain_free(struct iommu_domain *domain)
{
if (likely(domain->ops->domain_destroy != NULL))
domain->ops->domain_destroy(domain);
kfree(domain);
}
EXPORT_SYMBOL_GPL(iommu_domain_free);
int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
{
int ret;
if (unlikely(domain->ops->attach_dev == NULL))
return -ENODEV;
ret = domain->ops->attach_dev(domain, dev);
if (!ret)
trace_attach_device_to_domain(dev);
return ret;
}
EXPORT_SYMBOL_GPL(iommu_attach_device);
void iommu_detach_device(struct iommu_domain *domain, struct device *dev)
{
if (unlikely(domain->ops->detach_dev == NULL))
return;
domain->ops->detach_dev(domain, dev);
trace_detach_device_from_domain(dev);
}
EXPORT_SYMBOL_GPL(iommu_detach_device);
/*
* IOMMU groups are really the natrual working unit of the IOMMU, but
* the IOMMU API works on domains and devices. Bridge that gap by
* iterating over the devices in a group. Ideally we'd have a single
* device which represents the requestor ID of the group, but we also
* allow IOMMU drivers to create policy defined minimum sets, where
* the physical hardware may be able to distiguish members, but we
* wish to group them at a higher level (ex. untrusted multi-function
* PCI devices). Thus we attach each device.
*/
static int iommu_group_do_attach_device(struct device *dev, void *data)
{
struct iommu_domain *domain = data;
return iommu_attach_device(domain, dev);
}
int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
{
return iommu_group_for_each_dev(group, domain,
iommu_group_do_attach_device);
}
EXPORT_SYMBOL_GPL(iommu_attach_group);
static int iommu_group_do_detach_device(struct device *dev, void *data)
{
struct iommu_domain *domain = data;
iommu_detach_device(domain, dev);
return 0;
}
void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group)
{
iommu_group_for_each_dev(group, domain, iommu_group_do_detach_device);
}
EXPORT_SYMBOL_GPL(iommu_detach_group);
phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
{
if (unlikely(domain->ops->iova_to_phys == NULL))
return 0;
return domain->ops->iova_to_phys(domain, iova);
}
EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
static size_t iommu_pgsize(struct iommu_domain *domain,
unsigned long addr_merge, size_t size)
{
unsigned int pgsize_idx;
size_t pgsize;
/* Max page size that still fits into 'size' */
pgsize_idx = __fls(size);
/* need to consider alignment requirements ? */
if (likely(addr_merge)) {
/* Max page size allowed by address */
unsigned int align_pgsize_idx = __ffs(addr_merge);
pgsize_idx = min(pgsize_idx, align_pgsize_idx);
}
/* build a mask of acceptable page sizes */
pgsize = (1UL << (pgsize_idx + 1)) - 1;
/* throw away page sizes not supported by the hardware */
pgsize &= domain->ops->pgsize_bitmap;
/* make sure we're still sane */
BUG_ON(!pgsize);
/* pick the biggest page */
pgsize_idx = __fls(pgsize);
pgsize = 1UL << pgsize_idx;
return pgsize;
}
int iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
unsigned long orig_iova = iova;
unsigned int min_pagesz;
size_t orig_size = size;
int ret = 0;
if (unlikely(domain->ops->map == NULL ||
domain->ops->pgsize_bitmap == 0UL))
return -ENODEV;
/* find out the minimum page size supported */
min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
/*
* both the virtual address and the physical one, as well as
* the size of the mapping, must be aligned (at least) to the
* size of the smallest page supported by the hardware
*/
if (!IS_ALIGNED(iova | paddr | size, min_pagesz)) {
pr_err("unaligned: iova 0x%lx pa %pa size 0x%zx min_pagesz 0x%x\n",
iova, &paddr, size, min_pagesz);
return -EINVAL;
}
pr_debug("map: iova 0x%lx pa %pa size 0x%zx\n", iova, &paddr, size);
while (size) {
size_t pgsize = iommu_pgsize(domain, iova | paddr, size);
pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx\n",
iova, &paddr, pgsize);
ret = domain->ops->map(domain, iova, paddr, pgsize, prot);
if (ret)
break;
iova += pgsize;
paddr += pgsize;
size -= pgsize;
}
/* unroll mapping in case something went wrong */
if (ret)
iommu_unmap(domain, orig_iova, orig_size - size);
else
trace_map(iova, paddr, size);
return ret;
}
EXPORT_SYMBOL_GPL(iommu_map);
size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size)
{
size_t unmapped_page, unmapped = 0;
unsigned int min_pagesz;
if (unlikely(domain->ops->unmap == NULL ||
domain->ops->pgsize_bitmap == 0UL))
return -ENODEV;
/* find out the minimum page size supported */
min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
/*
* The virtual address, as well as the size of the mapping, must be
* aligned (at least) to the size of the smallest page supported
* by the hardware
*/
if (!IS_ALIGNED(iova | size, min_pagesz)) {
pr_err("unaligned: iova 0x%lx size 0x%zx min_pagesz 0x%x\n",
iova, size, min_pagesz);
return -EINVAL;
}
pr_debug("unmap this: iova 0x%lx size 0x%zx\n", iova, size);
/*
* Keep iterating until we either unmap 'size' bytes (or more)
* or we hit an area that isn't mapped.
*/
while (unmapped < size) {
size_t pgsize = iommu_pgsize(domain, iova, size - unmapped);
unmapped_page = domain->ops->unmap(domain, iova, pgsize);
if (!unmapped_page)
break;
pr_debug("unmapped: iova 0x%lx size 0x%zx\n",
iova, unmapped_page);
iova += unmapped_page;
unmapped += unmapped_page;
}
trace_unmap(iova, 0, size);
return unmapped;
}
EXPORT_SYMBOL_GPL(iommu_unmap);
size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
struct scatterlist *sg, unsigned int nents, int prot)
{
struct scatterlist *s;
size_t mapped = 0;
unsigned int i, min_pagesz;
int ret;
if (unlikely(domain->ops->pgsize_bitmap == 0UL))
return 0;
min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
for_each_sg(sg, s, nents, i) {
phys_addr_t phys = page_to_phys(sg_page(s)) + s->offset;
/*
* We are mapping on IOMMU page boundaries, so offset within
* the page must be 0. However, the IOMMU may support pages
* smaller than PAGE_SIZE, so s->offset may still represent
* an offset of that boundary within the CPU page.
*/
if (!IS_ALIGNED(s->offset, min_pagesz))
goto out_err;
ret = iommu_map(domain, iova + mapped, phys, s->length, prot);
if (ret)
goto out_err;
mapped += s->length;
}
return mapped;
out_err:
/* undo mappings already done */
iommu_unmap(domain, iova, mapped);
return 0;
}
EXPORT_SYMBOL_GPL(default_iommu_map_sg);
int iommu_domain_window_enable(struct iommu_domain *domain, u32 wnd_nr,
phys_addr_t paddr, u64 size, int prot)
{
if (unlikely(domain->ops->domain_window_enable == NULL))
return -ENODEV;
return domain->ops->domain_window_enable(domain, wnd_nr, paddr, size,
prot);
}
EXPORT_SYMBOL_GPL(iommu_domain_window_enable);
void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr)
{
if (unlikely(domain->ops->domain_window_disable == NULL))
return;
return domain->ops->domain_window_disable(domain, wnd_nr);
}
EXPORT_SYMBOL_GPL(iommu_domain_window_disable);
static int __init iommu_init(void)
{
iommu_group_kset = kset_create_and_add("iommu_groups",
NULL, kernel_kobj);
ida_init(&iommu_group_ida);
mutex_init(&iommu_group_mutex);
BUG_ON(!iommu_group_kset);
return 0;
}
arch_initcall(iommu_init);
int iommu_domain_get_attr(struct iommu_domain *domain,
enum iommu_attr attr, void *data)
{
struct iommu_domain_geometry *geometry;
bool *paging;
int ret = 0;
u32 *count;
switch (attr) {
case DOMAIN_ATTR_GEOMETRY:
geometry = data;
*geometry = domain->geometry;
break;
case DOMAIN_ATTR_PAGING:
paging = data;
*paging = (domain->ops->pgsize_bitmap != 0UL);
break;
case DOMAIN_ATTR_WINDOWS:
count = data;
if (domain->ops->domain_get_windows != NULL)
*count = domain->ops->domain_get_windows(domain);
else
ret = -ENODEV;
break;
default:
if (!domain->ops->domain_get_attr)
return -EINVAL;
ret = domain->ops->domain_get_attr(domain, attr, data);
}
return ret;
}
EXPORT_SYMBOL_GPL(iommu_domain_get_attr);
int iommu_domain_set_attr(struct iommu_domain *domain,
enum iommu_attr attr, void *data)
{
int ret = 0;
u32 *count;
switch (attr) {
case DOMAIN_ATTR_WINDOWS:
count = data;
if (domain->ops->domain_set_windows != NULL)
ret = domain->ops->domain_set_windows(domain, *count);
else
ret = -ENODEV;
break;
default:
if (domain->ops->domain_set_attr == NULL)
return -EINVAL;
ret = domain->ops->domain_set_attr(domain, attr, data);
}
return ret;
}
EXPORT_SYMBOL_GPL(iommu_domain_set_attr);
