--- /dev/null
+/*
+ * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
+ * Author: Joerg Roedel <jroedel@suse.de>
+ *
+ * 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;
+
+ if (bus == NULL || bus->iommu_ops == NULL)
+ return NULL;
+
+ domain = bus->iommu_ops->domain_alloc(IOMMU_DOMAIN_UNMANAGED);
+ if (!domain)
+ return NULL;
+
+ domain->ops = bus->iommu_ops;
+ domain->type = IOMMU_DOMAIN_UNMANAGED;
+
+ return domain;
+}
+EXPORT_SYMBOL_GPL(iommu_domain_alloc);
+
+void iommu_domain_free(struct iommu_domain *domain)
+{
+ domain->ops->domain_free(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;
+
+ if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
+ return -EINVAL;
+
+ /* 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(orig_iova, paddr, orig_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;
+ unsigned long orig_iova = iova;
+
+ if (unlikely(domain->ops->unmap == NULL ||
+ domain->ops->pgsize_bitmap == 0UL))
+ return -ENODEV;
+
+ if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
+ return -EINVAL;
+
+ /* 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(orig_iova, size, unmapped);
+ 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);
Code Review / kvmfornfv.git / blobdiff