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-rw-r--r--drivers/iommu/iommu.c3541
1 files changed, 3541 insertions, 0 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
new file mode 100644
index 000000000..3a67e6362
--- /dev/null
+++ b/drivers/iommu/iommu.c
@@ -0,0 +1,3541 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
+ * Author: Joerg Roedel <jroedel@suse.de>
+ */
+
+#define pr_fmt(fmt) "iommu: " fmt
+
+#include <linux/amba/bus.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/bits.h>
+#include <linux/bug.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/host1x_context_bus.h>
+#include <linux/iommu.h>
+#include <linux/idr.h>
+#include <linux/err.h>
+#include <linux/pci.h>
+#include <linux/pci-ats.h>
+#include <linux/bitops.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/fsl/mc.h>
+#include <linux/module.h>
+#include <linux/cc_platform.h>
+#include <linux/cdx/cdx_bus.h>
+#include <trace/events/iommu.h>
+#include <linux/sched/mm.h>
+#include <linux/msi.h>
+
+#include "dma-iommu.h"
+#include "iommu-priv.h"
+
+#include "iommu-sva.h"
+#include "iommu-priv.h"
+
+static struct kset *iommu_group_kset;
+static DEFINE_IDA(iommu_group_ida);
+static DEFINE_IDA(iommu_global_pasid_ida);
+
+static unsigned int iommu_def_domain_type __read_mostly;
+static bool iommu_dma_strict __read_mostly = IS_ENABLED(CONFIG_IOMMU_DEFAULT_DMA_STRICT);
+static u32 iommu_cmd_line __read_mostly;
+
+struct iommu_group {
+ struct kobject kobj;
+ struct kobject *devices_kobj;
+ struct list_head devices;
+ struct xarray pasid_array;
+ struct mutex mutex;
+ void *iommu_data;
+ void (*iommu_data_release)(void *iommu_data);
+ char *name;
+ int id;
+ struct iommu_domain *default_domain;
+ struct iommu_domain *blocking_domain;
+ struct iommu_domain *domain;
+ struct list_head entry;
+ unsigned int owner_cnt;
+ void *owner;
+};
+
+struct group_device {
+ struct list_head list;
+ struct device *dev;
+ char *name;
+};
+
+/* Iterate over each struct group_device in a struct iommu_group */
+#define for_each_group_device(group, pos) \
+ list_for_each_entry(pos, &(group)->devices, list)
+
+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);
+};
+
+static const char * const iommu_group_resv_type_string[] = {
+ [IOMMU_RESV_DIRECT] = "direct",
+ [IOMMU_RESV_DIRECT_RELAXABLE] = "direct-relaxable",
+ [IOMMU_RESV_RESERVED] = "reserved",
+ [IOMMU_RESV_MSI] = "msi",
+ [IOMMU_RESV_SW_MSI] = "msi",
+};
+
+#define IOMMU_CMD_LINE_DMA_API BIT(0)
+#define IOMMU_CMD_LINE_STRICT BIT(1)
+
+static int iommu_bus_notifier(struct notifier_block *nb,
+ unsigned long action, void *data);
+static void iommu_release_device(struct device *dev);
+static struct iommu_domain *__iommu_domain_alloc(const struct bus_type *bus,
+ unsigned type);
+static int __iommu_attach_device(struct iommu_domain *domain,
+ struct device *dev);
+static int __iommu_attach_group(struct iommu_domain *domain,
+ struct iommu_group *group);
+
+enum {
+ IOMMU_SET_DOMAIN_MUST_SUCCEED = 1 << 0,
+};
+
+static int __iommu_device_set_domain(struct iommu_group *group,
+ struct device *dev,
+ struct iommu_domain *new_domain,
+ unsigned int flags);
+static int __iommu_group_set_domain_internal(struct iommu_group *group,
+ struct iommu_domain *new_domain,
+ unsigned int flags);
+static int __iommu_group_set_domain(struct iommu_group *group,
+ struct iommu_domain *new_domain)
+{
+ return __iommu_group_set_domain_internal(group, new_domain, 0);
+}
+static void __iommu_group_set_domain_nofail(struct iommu_group *group,
+ struct iommu_domain *new_domain)
+{
+ WARN_ON(__iommu_group_set_domain_internal(
+ group, new_domain, IOMMU_SET_DOMAIN_MUST_SUCCEED));
+}
+
+static int iommu_setup_default_domain(struct iommu_group *group,
+ int target_type);
+static int iommu_create_device_direct_mappings(struct iommu_domain *domain,
+ struct device *dev);
+static ssize_t iommu_group_store_type(struct iommu_group *group,
+ const char *buf, size_t count);
+static struct group_device *iommu_group_alloc_device(struct iommu_group *group,
+ struct device *dev);
+static void __iommu_group_free_device(struct iommu_group *group,
+ struct group_device *grp_dev);
+
+#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 LIST_HEAD(iommu_device_list);
+static DEFINE_SPINLOCK(iommu_device_lock);
+
+static struct bus_type * const iommu_buses[] = {
+ &platform_bus_type,
+#ifdef CONFIG_PCI
+ &pci_bus_type,
+#endif
+#ifdef CONFIG_ARM_AMBA
+ &amba_bustype,
+#endif
+#ifdef CONFIG_FSL_MC_BUS
+ &fsl_mc_bus_type,
+#endif
+#ifdef CONFIG_TEGRA_HOST1X_CONTEXT_BUS
+ &host1x_context_device_bus_type,
+#endif
+#ifdef CONFIG_CDX_BUS
+ &cdx_bus_type,
+#endif
+};
+
+/*
+ * Use a function instead of an array here because the domain-type is a
+ * bit-field, so an array would waste memory.
+ */
+static const char *iommu_domain_type_str(unsigned int t)
+{
+ switch (t) {
+ case IOMMU_DOMAIN_BLOCKED:
+ return "Blocked";
+ case IOMMU_DOMAIN_IDENTITY:
+ return "Passthrough";
+ case IOMMU_DOMAIN_UNMANAGED:
+ return "Unmanaged";
+ case IOMMU_DOMAIN_DMA:
+ case IOMMU_DOMAIN_DMA_FQ:
+ return "Translated";
+ default:
+ return "Unknown";
+ }
+}
+
+static int __init iommu_subsys_init(void)
+{
+ struct notifier_block *nb;
+
+ if (!(iommu_cmd_line & IOMMU_CMD_LINE_DMA_API)) {
+ if (IS_ENABLED(CONFIG_IOMMU_DEFAULT_PASSTHROUGH))
+ iommu_set_default_passthrough(false);
+ else
+ iommu_set_default_translated(false);
+
+ if (iommu_default_passthrough() && cc_platform_has(CC_ATTR_MEM_ENCRYPT)) {
+ pr_info("Memory encryption detected - Disabling default IOMMU Passthrough\n");
+ iommu_set_default_translated(false);
+ }
+ }
+
+ if (!iommu_default_passthrough() && !iommu_dma_strict)
+ iommu_def_domain_type = IOMMU_DOMAIN_DMA_FQ;
+
+ pr_info("Default domain type: %s%s\n",
+ iommu_domain_type_str(iommu_def_domain_type),
+ (iommu_cmd_line & IOMMU_CMD_LINE_DMA_API) ?
+ " (set via kernel command line)" : "");
+
+ if (!iommu_default_passthrough())
+ pr_info("DMA domain TLB invalidation policy: %s mode%s\n",
+ iommu_dma_strict ? "strict" : "lazy",
+ (iommu_cmd_line & IOMMU_CMD_LINE_STRICT) ?
+ " (set via kernel command line)" : "");
+
+ nb = kcalloc(ARRAY_SIZE(iommu_buses), sizeof(*nb), GFP_KERNEL);
+ if (!nb)
+ return -ENOMEM;
+
+ for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++) {
+ nb[i].notifier_call = iommu_bus_notifier;
+ bus_register_notifier(iommu_buses[i], &nb[i]);
+ }
+
+ return 0;
+}
+subsys_initcall(iommu_subsys_init);
+
+static int remove_iommu_group(struct device *dev, void *data)
+{
+ if (dev->iommu && dev->iommu->iommu_dev == data)
+ iommu_release_device(dev);
+
+ return 0;
+}
+
+/**
+ * iommu_device_register() - Register an IOMMU hardware instance
+ * @iommu: IOMMU handle for the instance
+ * @ops: IOMMU ops to associate with the instance
+ * @hwdev: (optional) actual instance device, used for fwnode lookup
+ *
+ * Return: 0 on success, or an error.
+ */
+int iommu_device_register(struct iommu_device *iommu,
+ const struct iommu_ops *ops, struct device *hwdev)
+{
+ int err = 0;
+
+ /* 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)
+ iommu->fwnode = dev_fwnode(hwdev);
+
+ spin_lock(&iommu_device_lock);
+ 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;
+ err = bus_iommu_probe(iommu_buses[i]);
+ }
+ if (err)
+ iommu_device_unregister(iommu);
+ return err;
+}
+EXPORT_SYMBOL_GPL(iommu_device_register);
+
+void iommu_device_unregister(struct iommu_device *iommu)
+{
+ for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++)
+ bus_for_each_dev(iommu_buses[i], NULL, iommu, remove_iommu_group);
+
+ spin_lock(&iommu_device_lock);
+ list_del(&iommu->list);
+ spin_unlock(&iommu_device_lock);
+}
+EXPORT_SYMBOL_GPL(iommu_device_unregister);
+
+#if IS_ENABLED(CONFIG_IOMMUFD_TEST)
+void iommu_device_unregister_bus(struct iommu_device *iommu,
+ struct bus_type *bus,
+ struct notifier_block *nb)
+{
+ bus_unregister_notifier(bus, nb);
+ iommu_device_unregister(iommu);
+}
+EXPORT_SYMBOL_GPL(iommu_device_unregister_bus);
+
+/*
+ * Register an iommu driver against a single bus. This is only used by iommufd
+ * selftest to create a mock iommu driver. The caller must provide
+ * some memory to hold a notifier_block.
+ */
+int iommu_device_register_bus(struct iommu_device *iommu,
+ const struct iommu_ops *ops, struct bus_type *bus,
+ struct notifier_block *nb)
+{
+ int err;
+
+ iommu->ops = ops;
+ nb->notifier_call = iommu_bus_notifier;
+ err = bus_register_notifier(bus, nb);
+ if (err)
+ return err;
+
+ spin_lock(&iommu_device_lock);
+ 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);
+ return err;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_device_register_bus);
+#endif
+
+static struct dev_iommu *dev_iommu_get(struct device *dev)
+{
+ struct dev_iommu *param = dev->iommu;
+
+ if (param)
+ return param;
+
+ param = kzalloc(sizeof(*param), GFP_KERNEL);
+ if (!param)
+ return NULL;
+
+ mutex_init(&param->lock);
+ dev->iommu = param;
+ return param;
+}
+
+static void dev_iommu_free(struct device *dev)
+{
+ struct dev_iommu *param = dev->iommu;
+
+ dev->iommu = NULL;
+ if (param->fwspec) {
+ fwnode_handle_put(param->fwspec->iommu_fwnode);
+ kfree(param->fwspec);
+ }
+ kfree(param);
+}
+
+static u32 dev_iommu_get_max_pasids(struct device *dev)
+{
+ u32 max_pasids = 0, bits = 0;
+ int ret;
+
+ if (dev_is_pci(dev)) {
+ ret = pci_max_pasids(to_pci_dev(dev));
+ if (ret > 0)
+ max_pasids = ret;
+ } else {
+ ret = device_property_read_u32(dev, "pasid-num-bits", &bits);
+ if (!ret)
+ max_pasids = 1UL << bits;
+ }
+
+ return min_t(u32, max_pasids, dev->iommu->iommu_dev->max_pasids);
+}
+
+/*
+ * Init the dev->iommu and dev->iommu_group in the struct device and get the
+ * driver probed
+ */
+static int iommu_init_device(struct device *dev, const struct iommu_ops *ops)
+{
+ struct iommu_device *iommu_dev;
+ struct iommu_group *group;
+ int ret;
+
+ if (!dev_iommu_get(dev))
+ return -ENOMEM;
+
+ if (!try_module_get(ops->owner)) {
+ ret = -EINVAL;
+ goto err_free;
+ }
+
+ iommu_dev = ops->probe_device(dev);
+ if (IS_ERR(iommu_dev)) {
+ ret = PTR_ERR(iommu_dev);
+ goto err_module_put;
+ }
+
+ ret = iommu_device_link(iommu_dev, dev);
+ if (ret)
+ goto err_release;
+
+ group = ops->device_group(dev);
+ if (WARN_ON_ONCE(group == NULL))
+ group = ERR_PTR(-EINVAL);
+ if (IS_ERR(group)) {
+ ret = PTR_ERR(group);
+ goto err_unlink;
+ }
+ dev->iommu_group = group;
+
+ dev->iommu->iommu_dev = iommu_dev;
+ dev->iommu->max_pasids = dev_iommu_get_max_pasids(dev);
+ if (ops->is_attach_deferred)
+ dev->iommu->attach_deferred = ops->is_attach_deferred(dev);
+ return 0;
+
+err_unlink:
+ iommu_device_unlink(iommu_dev, dev);
+err_release:
+ if (ops->release_device)
+ ops->release_device(dev);
+err_module_put:
+ module_put(ops->owner);
+err_free:
+ dev_iommu_free(dev);
+ return ret;
+}
+
+static void iommu_deinit_device(struct device *dev)
+{
+ struct iommu_group *group = dev->iommu_group;
+ const struct iommu_ops *ops = dev_iommu_ops(dev);
+
+ lockdep_assert_held(&group->mutex);
+
+ iommu_device_unlink(dev->iommu->iommu_dev, dev);
+
+ /*
+ * release_device() must stop using any attached domain on the device.
+ * If there are still other devices in the group they are not effected
+ * by this callback.
+ *
+ * The IOMMU driver must set the device to either an identity or
+ * blocking translation and stop using any domain pointer, as it is
+ * going to be freed.
+ */
+ if (ops->release_device)
+ ops->release_device(dev);
+
+ /*
+ * If this is the last driver to use the group then we must free the
+ * domains before we do the module_put().
+ */
+ if (list_empty(&group->devices)) {
+ if (group->default_domain) {
+ iommu_domain_free(group->default_domain);
+ group->default_domain = NULL;
+ }
+ if (group->blocking_domain) {
+ iommu_domain_free(group->blocking_domain);
+ group->blocking_domain = NULL;
+ }
+ group->domain = NULL;
+ }
+
+ /* Caller must put iommu_group */
+ dev->iommu_group = NULL;
+ module_put(ops->owner);
+ dev_iommu_free(dev);
+}
+
+DEFINE_MUTEX(iommu_probe_device_lock);
+
+static int __iommu_probe_device(struct device *dev, struct list_head *group_list)
+{
+ const struct iommu_ops *ops = dev->bus->iommu_ops;
+ struct iommu_group *group;
+ struct group_device *gdev;
+ int ret;
+
+ if (!ops)
+ return -ENODEV;
+ /*
+ * Serialise to avoid races between IOMMU drivers registering in
+ * parallel and/or the "replay" calls from ACPI/OF code via client
+ * driver probe. Once the latter have been cleaned up we should
+ * probably be able to use device_lock() here to minimise the scope,
+ * but for now enforcing a simple global ordering is fine.
+ */
+ lockdep_assert_held(&iommu_probe_device_lock);
+
+ /* Device is probed already if in a group */
+ if (dev->iommu_group)
+ return 0;
+
+ ret = iommu_init_device(dev, ops);
+ if (ret)
+ return ret;
+
+ group = dev->iommu_group;
+ gdev = iommu_group_alloc_device(group, dev);
+ mutex_lock(&group->mutex);
+ if (IS_ERR(gdev)) {
+ ret = PTR_ERR(gdev);
+ goto err_put_group;
+ }
+
+ /*
+ * The gdev must be in the list before calling
+ * iommu_setup_default_domain()
+ */
+ list_add_tail(&gdev->list, &group->devices);
+ WARN_ON(group->default_domain && !group->domain);
+ if (group->default_domain)
+ iommu_create_device_direct_mappings(group->default_domain, dev);
+ if (group->domain) {
+ ret = __iommu_device_set_domain(group, dev, group->domain, 0);
+ if (ret)
+ goto err_remove_gdev;
+ } else if (!group->default_domain && !group_list) {
+ ret = iommu_setup_default_domain(group, 0);
+ if (ret)
+ goto err_remove_gdev;
+ } else if (!group->default_domain) {
+ /*
+ * With a group_list argument we defer the default_domain setup
+ * to the caller by providing a de-duplicated list of groups
+ * that need further setup.
+ */
+ if (list_empty(&group->entry))
+ list_add_tail(&group->entry, group_list);
+ }
+ mutex_unlock(&group->mutex);
+
+ if (dev_is_pci(dev))
+ iommu_dma_set_pci_32bit_workaround(dev);
+
+ return 0;
+
+err_remove_gdev:
+ list_del(&gdev->list);
+ __iommu_group_free_device(group, gdev);
+err_put_group:
+ iommu_deinit_device(dev);
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+
+ return ret;
+}
+
+int iommu_probe_device(struct device *dev)
+{
+ const struct iommu_ops *ops;
+ int ret;
+
+ mutex_lock(&iommu_probe_device_lock);
+ ret = __iommu_probe_device(dev, NULL);
+ mutex_unlock(&iommu_probe_device_lock);
+ if (ret)
+ return ret;
+
+ ops = dev_iommu_ops(dev);
+ if (ops->probe_finalize)
+ ops->probe_finalize(dev);
+
+ return 0;
+}
+
+static void __iommu_group_free_device(struct iommu_group *group,
+ struct group_device *grp_dev)
+{
+ struct device *dev = grp_dev->dev;
+
+ sysfs_remove_link(group->devices_kobj, grp_dev->name);
+ sysfs_remove_link(&dev->kobj, "iommu_group");
+
+ trace_remove_device_from_group(group->id, dev);
+
+ /*
+ * If the group has become empty then ownership must have been
+ * released, and the current domain must be set back to NULL or
+ * the default domain.
+ */
+ if (list_empty(&group->devices))
+ WARN_ON(group->owner_cnt ||
+ group->domain != group->default_domain);
+
+ kfree(grp_dev->name);
+ kfree(grp_dev);
+}
+
+/* Remove the iommu_group from the struct device. */
+static void __iommu_group_remove_device(struct device *dev)
+{
+ struct iommu_group *group = dev->iommu_group;
+ struct group_device *device;
+
+ mutex_lock(&group->mutex);
+ for_each_group_device(group, device) {
+ if (device->dev != dev)
+ continue;
+
+ list_del(&device->list);
+ __iommu_group_free_device(group, device);
+ if (dev->iommu && dev->iommu->iommu_dev)
+ iommu_deinit_device(dev);
+ else
+ dev->iommu_group = NULL;
+ break;
+ }
+ mutex_unlock(&group->mutex);
+
+ /*
+ * Pairs with the get in iommu_init_device() or
+ * iommu_group_add_device()
+ */
+ iommu_group_put(group);
+}
+
+static void iommu_release_device(struct device *dev)
+{
+ struct iommu_group *group = dev->iommu_group;
+
+ if (group)
+ __iommu_group_remove_device(dev);
+
+ /* Free any fwspec if no iommu_driver was ever attached */
+ if (dev->iommu)
+ dev_iommu_free(dev);
+}
+
+static int __init iommu_set_def_domain_type(char *str)
+{
+ bool pt;
+ int ret;
+
+ ret = kstrtobool(str, &pt);
+ if (ret)
+ return ret;
+
+ if (pt)
+ iommu_set_default_passthrough(true);
+ else
+ iommu_set_default_translated(true);
+
+ return 0;
+}
+early_param("iommu.passthrough", iommu_set_def_domain_type);
+
+static int __init iommu_dma_setup(char *str)
+{
+ int ret = kstrtobool(str, &iommu_dma_strict);
+
+ if (!ret)
+ iommu_cmd_line |= IOMMU_CMD_LINE_STRICT;
+ return ret;
+}
+early_param("iommu.strict", iommu_dma_setup);
+
+void iommu_set_dma_strict(void)
+{
+ iommu_dma_strict = true;
+ if (iommu_def_domain_type == IOMMU_DOMAIN_DMA_FQ)
+ iommu_def_domain_type = IOMMU_DOMAIN_DMA;
+}
+
+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 sysfs_emit(buf, "%s\n", group->name);
+}
+
+/**
+ * iommu_insert_resv_region - Insert a new region in the
+ * list of reserved regions.
+ * @new: new region to insert
+ * @regions: list of regions
+ *
+ * Elements are sorted by start address and overlapping segments
+ * of the same type are merged.
+ */
+static int iommu_insert_resv_region(struct iommu_resv_region *new,
+ struct list_head *regions)
+{
+ struct iommu_resv_region *iter, *tmp, *nr, *top;
+ LIST_HEAD(stack);
+
+ nr = iommu_alloc_resv_region(new->start, new->length,
+ new->prot, new->type, GFP_KERNEL);
+ if (!nr)
+ return -ENOMEM;
+
+ /* First add the new element based on start address sorting */
+ list_for_each_entry(iter, regions, list) {
+ if (nr->start < iter->start ||
+ (nr->start == iter->start && nr->type <= iter->type))
+ break;
+ }
+ list_add_tail(&nr->list, &iter->list);
+
+ /* Merge overlapping segments of type nr->type in @regions, if any */
+ list_for_each_entry_safe(iter, tmp, regions, list) {
+ phys_addr_t top_end, iter_end = iter->start + iter->length - 1;
+
+ /* no merge needed on elements of different types than @new */
+ if (iter->type != new->type) {
+ list_move_tail(&iter->list, &stack);
+ continue;
+ }
+
+ /* look for the last stack element of same type as @iter */
+ list_for_each_entry_reverse(top, &stack, list)
+ if (top->type == iter->type)
+ goto check_overlap;
+
+ list_move_tail(&iter->list, &stack);
+ continue;
+
+check_overlap:
+ top_end = top->start + top->length - 1;
+
+ if (iter->start > top_end + 1) {
+ list_move_tail(&iter->list, &stack);
+ } else {
+ top->length = max(top_end, iter_end) - top->start + 1;
+ list_del(&iter->list);
+ kfree(iter);
+ }
+ }
+ list_splice(&stack, regions);
+ return 0;
+}
+
+static int
+iommu_insert_device_resv_regions(struct list_head *dev_resv_regions,
+ struct list_head *group_resv_regions)
+{
+ struct iommu_resv_region *entry;
+ int ret = 0;
+
+ list_for_each_entry(entry, dev_resv_regions, list) {
+ ret = iommu_insert_resv_region(entry, group_resv_regions);
+ if (ret)
+ break;
+ }
+ return ret;
+}
+
+int iommu_get_group_resv_regions(struct iommu_group *group,
+ struct list_head *head)
+{
+ struct group_device *device;
+ int ret = 0;
+
+ mutex_lock(&group->mutex);
+ for_each_group_device(group, device) {
+ struct list_head dev_resv_regions;
+
+ /*
+ * Non-API groups still expose reserved_regions in sysfs,
+ * so filter out calls that get here that way.
+ */
+ if (!device->dev->iommu)
+ break;
+
+ INIT_LIST_HEAD(&dev_resv_regions);
+ iommu_get_resv_regions(device->dev, &dev_resv_regions);
+ ret = iommu_insert_device_resv_regions(&dev_resv_regions, head);
+ iommu_put_resv_regions(device->dev, &dev_resv_regions);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&group->mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_get_group_resv_regions);
+
+static ssize_t iommu_group_show_resv_regions(struct iommu_group *group,
+ char *buf)
+{
+ struct iommu_resv_region *region, *next;
+ struct list_head group_resv_regions;
+ int offset = 0;
+
+ INIT_LIST_HEAD(&group_resv_regions);
+ iommu_get_group_resv_regions(group, &group_resv_regions);
+
+ list_for_each_entry_safe(region, next, &group_resv_regions, list) {
+ offset += sysfs_emit_at(buf, offset, "0x%016llx 0x%016llx %s\n",
+ (long long)region->start,
+ (long long)(region->start +
+ region->length - 1),
+ iommu_group_resv_type_string[region->type]);
+ kfree(region);
+ }
+
+ return offset;
+}
+
+static ssize_t iommu_group_show_type(struct iommu_group *group,
+ char *buf)
+{
+ char *type = "unknown";
+
+ mutex_lock(&group->mutex);
+ if (group->default_domain) {
+ switch (group->default_domain->type) {
+ case IOMMU_DOMAIN_BLOCKED:
+ type = "blocked";
+ break;
+ case IOMMU_DOMAIN_IDENTITY:
+ type = "identity";
+ break;
+ case IOMMU_DOMAIN_UNMANAGED:
+ type = "unmanaged";
+ break;
+ case IOMMU_DOMAIN_DMA:
+ type = "DMA";
+ break;
+ case IOMMU_DOMAIN_DMA_FQ:
+ type = "DMA-FQ";
+ break;
+ }
+ }
+ mutex_unlock(&group->mutex);
+
+ return sysfs_emit(buf, "%s\n", type);
+}
+
+static IOMMU_GROUP_ATTR(name, S_IRUGO, iommu_group_show_name, NULL);
+
+static IOMMU_GROUP_ATTR(reserved_regions, 0444,
+ iommu_group_show_resv_regions, NULL);
+
+static IOMMU_GROUP_ATTR(type, 0644, iommu_group_show_type,
+ iommu_group_store_type);
+
+static void iommu_group_release(struct kobject *kobj)
+{
+ struct iommu_group *group = to_iommu_group(kobj);
+
+ pr_debug("Releasing group %d\n", group->id);
+
+ if (group->iommu_data_release)
+ group->iommu_data_release(group->iommu_data);
+
+ ida_free(&iommu_group_ida, group->id);
+
+ /* Domains are free'd by iommu_deinit_device() */
+ WARN_ON(group->default_domain);
+ WARN_ON(group->blocking_domain);
+
+ kfree(group->name);
+ kfree(group);
+}
+
+static const struct kobj_type iommu_group_ktype = {
+ .sysfs_ops = &iommu_group_sysfs_ops,
+ .release = iommu_group_release,
+};
+
+/**
+ * iommu_group_alloc - Allocate a new group
+ *
+ * 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);
+ INIT_LIST_HEAD(&group->entry);
+ xa_init(&group->pasid_array);
+
+ ret = ida_alloc(&iommu_group_ida, GFP_KERNEL);
+ if (ret < 0) {
+ kfree(group);
+ return ERR_PTR(ret);
+ }
+ group->id = ret;
+
+ ret = kobject_init_and_add(&group->kobj, &iommu_group_ktype,
+ NULL, "%d", group->id);
+ if (ret) {
+ kobject_put(&group->kobj);
+ 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);
+
+ ret = iommu_group_create_file(group,
+ &iommu_group_attr_reserved_regions);
+ if (ret) {
+ kobject_put(group->devices_kobj);
+ return ERR_PTR(ret);
+ }
+
+ ret = iommu_group_create_file(group, &iommu_group_attr_type);
+ if (ret) {
+ kobject_put(group->devices_kobj);
+ return ERR_PTR(ret);
+ }
+
+ pr_debug("Allocated group %d\n", group->id);
+
+ return group;
+}
+EXPORT_SYMBOL_GPL(iommu_group_alloc);
+
+/**
+ * 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);
+
+static int iommu_create_device_direct_mappings(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct iommu_resv_region *entry;
+ struct list_head mappings;
+ unsigned long pg_size;
+ int ret = 0;
+
+ pg_size = domain->pgsize_bitmap ? 1UL << __ffs(domain->pgsize_bitmap) : 0;
+ INIT_LIST_HEAD(&mappings);
+
+ if (WARN_ON_ONCE(iommu_is_dma_domain(domain) && !pg_size))
+ return -EINVAL;
+
+ iommu_get_resv_regions(dev, &mappings);
+
+ /* We need to consider overlapping regions for different devices */
+ list_for_each_entry(entry, &mappings, list) {
+ dma_addr_t start, end, addr;
+ size_t map_size = 0;
+
+ if (entry->type == IOMMU_RESV_DIRECT)
+ dev->iommu->require_direct = 1;
+
+ if ((entry->type != IOMMU_RESV_DIRECT &&
+ entry->type != IOMMU_RESV_DIRECT_RELAXABLE) ||
+ !iommu_is_dma_domain(domain))
+ continue;
+
+ start = ALIGN(entry->start, pg_size);
+ end = ALIGN(entry->start + entry->length, pg_size);
+
+ for (addr = start; addr <= end; addr += pg_size) {
+ phys_addr_t phys_addr;
+
+ if (addr == end)
+ goto map_end;
+
+ phys_addr = iommu_iova_to_phys(domain, addr);
+ if (!phys_addr) {
+ map_size += pg_size;
+ continue;
+ }
+
+map_end:
+ if (map_size) {
+ ret = iommu_map(domain, addr - map_size,
+ addr - map_size, map_size,
+ entry->prot, GFP_KERNEL);
+ if (ret)
+ goto out;
+ map_size = 0;
+ }
+ }
+
+ }
+
+ if (!list_empty(&mappings) && iommu_is_dma_domain(domain))
+ iommu_flush_iotlb_all(domain);
+
+out:
+ iommu_put_resv_regions(dev, &mappings);
+
+ return ret;
+}
+
+/* This is undone by __iommu_group_free_device() */
+static struct group_device *iommu_group_alloc_device(struct iommu_group *group,
+ struct device *dev)
+{
+ int ret, i = 0;
+ struct group_device *device;
+
+ device = kzalloc(sizeof(*device), GFP_KERNEL);
+ if (!device)
+ return ERR_PTR(-ENOMEM);
+
+ device->dev = dev;
+
+ ret = sysfs_create_link(&dev->kobj, &group->kobj, "iommu_group");
+ if (ret)
+ goto err_free_device;
+
+ device->name = kasprintf(GFP_KERNEL, "%s", kobject_name(&dev->kobj));
+rename:
+ if (!device->name) {
+ ret = -ENOMEM;
+ goto err_remove_link;
+ }
+
+ ret = sysfs_create_link_nowarn(group->devices_kobj,
+ &dev->kobj, device->name);
+ if (ret) {
+ if (ret == -EEXIST && i >= 0) {
+ /*
+ * Account for the slim chance of collision
+ * and append an instance to the name.
+ */
+ kfree(device->name);
+ device->name = kasprintf(GFP_KERNEL, "%s.%d",
+ kobject_name(&dev->kobj), i++);
+ goto rename;
+ }
+ goto err_free_name;
+ }
+
+ trace_add_device_to_group(group->id, dev);
+
+ dev_info(dev, "Adding to iommu group %d\n", group->id);
+
+ return device;
+
+err_free_name:
+ kfree(device->name);
+err_remove_link:
+ sysfs_remove_link(&dev->kobj, "iommu_group");
+err_free_device:
+ kfree(device);
+ dev_err(dev, "Failed to add to iommu group %d: %d\n", group->id, ret);
+ return ERR_PTR(ret);
+}
+
+/**
+ * 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)
+{
+ struct group_device *gdev;
+
+ gdev = iommu_group_alloc_device(group, dev);
+ if (IS_ERR(gdev))
+ return PTR_ERR(gdev);
+
+ iommu_group_ref_get(group);
+ dev->iommu_group = group;
+
+ mutex_lock(&group->mutex);
+ list_add_tail(&gdev->list, &group->devices);
+ mutex_unlock(&group->mutex);
+ 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;
+
+ if (!group)
+ return;
+
+ dev_info(dev, "Removing from iommu group %d\n", group->id);
+
+ __iommu_group_remove_device(dev);
+}
+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 group_device *device;
+ int ret = 0;
+
+ mutex_lock(&group->mutex);
+ for_each_group_device(group, device) {
+ 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_ref_get - Increment reference on a group
+ * @group: the group to use, must not be NULL
+ *
+ * This function is called by iommu drivers to take additional references on an
+ * existing group. Returns the given group for convenience.
+ */
+struct iommu_group *iommu_group_ref_get(struct iommu_group *group)
+{
+ kobject_get(group->devices_kobj);
+ return group;
+}
+EXPORT_SYMBOL_GPL(iommu_group_ref_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_register_device_fault_handler() - Register a device fault handler
+ * @dev: the device
+ * @handler: the fault handler
+ * @data: private data passed as argument to the handler
+ *
+ * When an IOMMU fault event is received, this handler gets called with the
+ * fault event and data as argument. The handler should return 0 on success. If
+ * the fault is recoverable (IOMMU_FAULT_PAGE_REQ), the consumer should also
+ * complete the fault by calling iommu_page_response() with one of the following
+ * response code:
+ * - IOMMU_PAGE_RESP_SUCCESS: retry the translation
+ * - IOMMU_PAGE_RESP_INVALID: terminate the fault
+ * - IOMMU_PAGE_RESP_FAILURE: terminate the fault and stop reporting
+ * page faults if possible.
+ *
+ * Return 0 if the fault handler was installed successfully, or an error.
+ */
+int iommu_register_device_fault_handler(struct device *dev,
+ iommu_dev_fault_handler_t handler,
+ void *data)
+{
+ struct dev_iommu *param = dev->iommu;
+ int ret = 0;
+
+ if (!param)
+ return -EINVAL;
+
+ mutex_lock(&param->lock);
+ /* Only allow one fault handler registered for each device */
+ if (param->fault_param) {
+ ret = -EBUSY;
+ goto done_unlock;
+ }
+
+ get_device(dev);
+ param->fault_param = kzalloc(sizeof(*param->fault_param), GFP_KERNEL);
+ if (!param->fault_param) {
+ put_device(dev);
+ ret = -ENOMEM;
+ goto done_unlock;
+ }
+ param->fault_param->handler = handler;
+ param->fault_param->data = data;
+ mutex_init(&param->fault_param->lock);
+ INIT_LIST_HEAD(&param->fault_param->faults);
+
+done_unlock:
+ mutex_unlock(&param->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_register_device_fault_handler);
+
+/**
+ * iommu_unregister_device_fault_handler() - Unregister the device fault handler
+ * @dev: the device
+ *
+ * Remove the device fault handler installed with
+ * iommu_register_device_fault_handler().
+ *
+ * Return 0 on success, or an error.
+ */
+int iommu_unregister_device_fault_handler(struct device *dev)
+{
+ struct dev_iommu *param = dev->iommu;
+ int ret = 0;
+
+ if (!param)
+ return -EINVAL;
+
+ mutex_lock(&param->lock);
+
+ if (!param->fault_param)
+ goto unlock;
+
+ /* we cannot unregister handler if there are pending faults */
+ if (!list_empty(&param->fault_param->faults)) {
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ kfree(param->fault_param);
+ param->fault_param = NULL;
+ put_device(dev);
+unlock:
+ mutex_unlock(&param->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_unregister_device_fault_handler);
+
+/**
+ * iommu_report_device_fault() - Report fault event to device driver
+ * @dev: the device
+ * @evt: fault event data
+ *
+ * Called by IOMMU drivers when a fault is detected, typically in a threaded IRQ
+ * handler. When this function fails and the fault is recoverable, it is the
+ * caller's responsibility to complete the fault.
+ *
+ * Return 0 on success, or an error.
+ */
+int iommu_report_device_fault(struct device *dev, struct iommu_fault_event *evt)
+{
+ struct dev_iommu *param = dev->iommu;
+ struct iommu_fault_event *evt_pending = NULL;
+ struct iommu_fault_param *fparam;
+ int ret = 0;
+
+ if (!param || !evt)
+ return -EINVAL;
+
+ /* we only report device fault if there is a handler registered */
+ mutex_lock(&param->lock);
+ fparam = param->fault_param;
+ if (!fparam || !fparam->handler) {
+ ret = -EINVAL;
+ goto done_unlock;
+ }
+
+ if (evt->fault.type == IOMMU_FAULT_PAGE_REQ &&
+ (evt->fault.prm.flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE)) {
+ evt_pending = kmemdup(evt, sizeof(struct iommu_fault_event),
+ GFP_KERNEL);
+ if (!evt_pending) {
+ ret = -ENOMEM;
+ goto done_unlock;
+ }
+ mutex_lock(&fparam->lock);
+ list_add_tail(&evt_pending->list, &fparam->faults);
+ mutex_unlock(&fparam->lock);
+ }
+
+ ret = fparam->handler(&evt->fault, fparam->data);
+ if (ret && evt_pending) {
+ mutex_lock(&fparam->lock);
+ list_del(&evt_pending->list);
+ mutex_unlock(&fparam->lock);
+ kfree(evt_pending);
+ }
+done_unlock:
+ mutex_unlock(&param->lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_report_device_fault);
+
+int iommu_page_response(struct device *dev,
+ struct iommu_page_response *msg)
+{
+ bool needs_pasid;
+ int ret = -EINVAL;
+ struct iommu_fault_event *evt;
+ struct iommu_fault_page_request *prm;
+ struct dev_iommu *param = dev->iommu;
+ const struct iommu_ops *ops = dev_iommu_ops(dev);
+ bool has_pasid = msg->flags & IOMMU_PAGE_RESP_PASID_VALID;
+
+ if (!ops->page_response)
+ return -ENODEV;
+
+ if (!param || !param->fault_param)
+ return -EINVAL;
+
+ if (msg->version != IOMMU_PAGE_RESP_VERSION_1 ||
+ msg->flags & ~IOMMU_PAGE_RESP_PASID_VALID)
+ return -EINVAL;
+
+ /* Only send response if there is a fault report pending */
+ mutex_lock(&param->fault_param->lock);
+ if (list_empty(&param->fault_param->faults)) {
+ dev_warn_ratelimited(dev, "no pending PRQ, drop response\n");
+ goto done_unlock;
+ }
+ /*
+ * Check if we have a matching page request pending to respond,
+ * otherwise return -EINVAL
+ */
+ list_for_each_entry(evt, &param->fault_param->faults, list) {
+ prm = &evt->fault.prm;
+ if (prm->grpid != msg->grpid)
+ continue;
+
+ /*
+ * If the PASID is required, the corresponding request is
+ * matched using the group ID, the PASID valid bit and the PASID
+ * value. Otherwise only the group ID matches request and
+ * response.
+ */
+ needs_pasid = prm->flags & IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID;
+ if (needs_pasid && (!has_pasid || msg->pasid != prm->pasid))
+ continue;
+
+ if (!needs_pasid && has_pasid) {
+ /* No big deal, just clear it. */
+ msg->flags &= ~IOMMU_PAGE_RESP_PASID_VALID;
+ msg->pasid = 0;
+ }
+
+ ret = ops->page_response(dev, evt, msg);
+ list_del(&evt->list);
+ kfree(evt);
+ break;
+ }
+
+done_unlock:
+ mutex_unlock(&param->fault_param->lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_page_response);
+
+/**
+ * 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 existing groups. DMA
+ * aliases are only supported 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 (pci_devs_are_dma_aliases(pdev, tmp)) {
+ 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;
+}
+
+/*
+ * Generic device_group call-back function. It just allocates one
+ * iommu-group per device.
+ */
+struct iommu_group *generic_device_group(struct device *dev)
+{
+ return iommu_group_alloc();
+}
+EXPORT_SYMBOL_GPL(generic_device_group);
+
+/*
+ * Use standard PCI bus topology, isolation features, and DMA alias quirks
+ * to find or create an IOMMU group for a device.
+ */
+struct iommu_group *pci_device_group(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct group_for_pci_data data;
+ struct pci_bus *bus;
+ struct iommu_group *group = NULL;
+ u64 devfns[4] = { 0 };
+
+ if (WARN_ON(!dev_is_pci(dev)))
+ return ERR_PTR(-EINVAL);
+
+ /*
+ * 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();
+}
+EXPORT_SYMBOL_GPL(pci_device_group);
+
+/* Get the IOMMU group for device on fsl-mc bus */
+struct iommu_group *fsl_mc_device_group(struct device *dev)
+{
+ struct device *cont_dev = fsl_mc_cont_dev(dev);
+ struct iommu_group *group;
+
+ group = iommu_group_get(cont_dev);
+ if (!group)
+ group = iommu_group_alloc();
+ return group;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_device_group);
+
+static int iommu_get_def_domain_type(struct device *dev)
+{
+ const struct iommu_ops *ops = dev_iommu_ops(dev);
+
+ if (dev_is_pci(dev) && to_pci_dev(dev)->untrusted)
+ return IOMMU_DOMAIN_DMA;
+
+ if (ops->def_domain_type)
+ return ops->def_domain_type(dev);
+
+ return 0;
+}
+
+static struct iommu_domain *
+__iommu_group_alloc_default_domain(const struct bus_type *bus,
+ struct iommu_group *group, int req_type)
+{
+ if (group->default_domain && group->default_domain->type == req_type)
+ return group->default_domain;
+ return __iommu_domain_alloc(bus, req_type);
+}
+
+/*
+ * req_type of 0 means "auto" which means to select a domain based on
+ * iommu_def_domain_type or what the driver actually supports.
+ */
+static struct iommu_domain *
+iommu_group_alloc_default_domain(struct iommu_group *group, int req_type)
+{
+ const struct bus_type *bus =
+ list_first_entry(&group->devices, struct group_device, list)
+ ->dev->bus;
+ struct iommu_domain *dom;
+
+ lockdep_assert_held(&group->mutex);
+
+ if (req_type)
+ return __iommu_group_alloc_default_domain(bus, group, req_type);
+
+ /* The driver gave no guidance on what type to use, try the default */
+ dom = __iommu_group_alloc_default_domain(bus, group, iommu_def_domain_type);
+ if (dom)
+ return dom;
+
+ /* Otherwise IDENTITY and DMA_FQ defaults will try DMA */
+ if (iommu_def_domain_type == IOMMU_DOMAIN_DMA)
+ return NULL;
+ dom = __iommu_group_alloc_default_domain(bus, group, IOMMU_DOMAIN_DMA);
+ if (!dom)
+ return NULL;
+
+ pr_warn("Failed to allocate default IOMMU domain of type %u for group %s - Falling back to IOMMU_DOMAIN_DMA",
+ iommu_def_domain_type, group->name);
+ return dom;
+}
+
+struct iommu_domain *iommu_group_default_domain(struct iommu_group *group)
+{
+ return group->default_domain;
+}
+
+static int probe_iommu_group(struct device *dev, void *data)
+{
+ struct list_head *group_list = data;
+ int ret;
+
+ mutex_lock(&iommu_probe_device_lock);
+ ret = __iommu_probe_device(dev, group_list);
+ mutex_unlock(&iommu_probe_device_lock);
+ if (ret == -ENODEV)
+ ret = 0;
+
+ return ret;
+}
+
+static int iommu_bus_notifier(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+
+ if (action == BUS_NOTIFY_ADD_DEVICE) {
+ int ret;
+
+ ret = iommu_probe_device(dev);
+ return (ret) ? NOTIFY_DONE : NOTIFY_OK;
+ } else if (action == BUS_NOTIFY_REMOVED_DEVICE) {
+ iommu_release_device(dev);
+ return NOTIFY_OK;
+ }
+
+ return 0;
+}
+
+/* A target_type of 0 will select the best domain type and cannot fail */
+static int iommu_get_default_domain_type(struct iommu_group *group,
+ int target_type)
+{
+ int best_type = target_type;
+ struct group_device *gdev;
+ struct device *last_dev;
+
+ lockdep_assert_held(&group->mutex);
+
+ for_each_group_device(group, gdev) {
+ unsigned int type = iommu_get_def_domain_type(gdev->dev);
+
+ if (best_type && type && best_type != type) {
+ if (target_type) {
+ dev_err_ratelimited(
+ gdev->dev,
+ "Device cannot be in %s domain\n",
+ iommu_domain_type_str(target_type));
+ return -1;
+ }
+
+ dev_warn(
+ gdev->dev,
+ "Device needs domain type %s, but device %s in the same iommu group requires type %s - using default\n",
+ iommu_domain_type_str(type), dev_name(last_dev),
+ iommu_domain_type_str(best_type));
+ return 0;
+ }
+ if (!best_type)
+ best_type = type;
+ last_dev = gdev->dev;
+ }
+ return best_type;
+}
+
+static void iommu_group_do_probe_finalize(struct device *dev)
+{
+ const struct iommu_ops *ops = dev_iommu_ops(dev);
+
+ if (ops->probe_finalize)
+ ops->probe_finalize(dev);
+}
+
+int bus_iommu_probe(const struct bus_type *bus)
+{
+ struct iommu_group *group, *next;
+ LIST_HEAD(group_list);
+ int ret;
+
+ ret = bus_for_each_dev(bus, NULL, &group_list, probe_iommu_group);
+ if (ret)
+ return ret;
+
+ list_for_each_entry_safe(group, next, &group_list, entry) {
+ struct group_device *gdev;
+
+ mutex_lock(&group->mutex);
+
+ /* Remove item from the list */
+ list_del_init(&group->entry);
+
+ /*
+ * We go to the trouble of deferred default domain creation so
+ * that the cross-group default domain type and the setup of the
+ * IOMMU_RESV_DIRECT will work correctly in non-hotpug scenarios.
+ */
+ ret = iommu_setup_default_domain(group, 0);
+ if (ret) {
+ mutex_unlock(&group->mutex);
+ return ret;
+ }
+ mutex_unlock(&group->mutex);
+
+ /*
+ * FIXME: Mis-locked because the ops->probe_finalize() call-back
+ * of some IOMMU drivers calls arm_iommu_attach_device() which
+ * in-turn might call back into IOMMU core code, where it tries
+ * to take group->mutex, resulting in a deadlock.
+ */
+ for_each_group_device(group, gdev)
+ iommu_group_do_probe_finalize(gdev->dev);
+ }
+
+ return 0;
+}
+
+bool iommu_present(const struct bus_type *bus)
+{
+ return bus->iommu_ops != NULL;
+}
+EXPORT_SYMBOL_GPL(iommu_present);
+
+/**
+ * device_iommu_capable() - check for a general IOMMU capability
+ * @dev: device to which the capability would be relevant, if available
+ * @cap: IOMMU capability
+ *
+ * Return: true if an IOMMU is present and supports the given capability
+ * for the given device, otherwise false.
+ */
+bool device_iommu_capable(struct device *dev, enum iommu_cap cap)
+{
+ const struct iommu_ops *ops;
+
+ if (!dev->iommu || !dev->iommu->iommu_dev)
+ return false;
+
+ ops = dev_iommu_ops(dev);
+ if (!ops->capable)
+ return false;
+
+ return ops->capable(dev, cap);
+}
+EXPORT_SYMBOL_GPL(device_iommu_capable);
+
+/**
+ * iommu_group_has_isolated_msi() - Compute msi_device_has_isolated_msi()
+ * for a group
+ * @group: Group to query
+ *
+ * IOMMU groups should not have differing values of
+ * msi_device_has_isolated_msi() for devices in a group. However nothing
+ * directly prevents this, so ensure mistakes don't result in isolation failures
+ * by checking that all the devices are the same.
+ */
+bool iommu_group_has_isolated_msi(struct iommu_group *group)
+{
+ struct group_device *group_dev;
+ bool ret = true;
+
+ mutex_lock(&group->mutex);
+ for_each_group_device(group, group_dev)
+ ret &= msi_device_has_isolated_msi(group_dev->dev);
+ mutex_unlock(&group->mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_group_has_isolated_msi);
+
+/**
+ * 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);
+
+static struct iommu_domain *__iommu_domain_alloc(const struct bus_type *bus,
+ unsigned type)
+{
+ struct iommu_domain *domain;
+ unsigned int alloc_type = type & IOMMU_DOMAIN_ALLOC_FLAGS;
+
+ if (bus == NULL || bus->iommu_ops == NULL)
+ return NULL;
+
+ domain = bus->iommu_ops->domain_alloc(alloc_type);
+ if (!domain)
+ return NULL;
+
+ domain->type = type;
+ /*
+ * If not already set, assume all sizes by default; the driver
+ * may override this later
+ */
+ if (!domain->pgsize_bitmap)
+ domain->pgsize_bitmap = bus->iommu_ops->pgsize_bitmap;
+
+ if (!domain->ops)
+ domain->ops = bus->iommu_ops->default_domain_ops;
+
+ if (iommu_is_dma_domain(domain) && iommu_get_dma_cookie(domain)) {
+ iommu_domain_free(domain);
+ domain = NULL;
+ }
+ return domain;
+}
+
+struct iommu_domain *iommu_domain_alloc(const struct bus_type *bus)
+{
+ return __iommu_domain_alloc(bus, IOMMU_DOMAIN_UNMANAGED);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_alloc);
+
+void iommu_domain_free(struct iommu_domain *domain)
+{
+ if (domain->type == IOMMU_DOMAIN_SVA)
+ mmdrop(domain->mm);
+ iommu_put_dma_cookie(domain);
+ domain->ops->free(domain);
+}
+EXPORT_SYMBOL_GPL(iommu_domain_free);
+
+/*
+ * Put the group's domain back to the appropriate core-owned domain - either the
+ * standard kernel-mode DMA configuration or an all-DMA-blocked domain.
+ */
+static void __iommu_group_set_core_domain(struct iommu_group *group)
+{
+ struct iommu_domain *new_domain;
+
+ if (group->owner)
+ new_domain = group->blocking_domain;
+ else
+ new_domain = group->default_domain;
+
+ __iommu_group_set_domain_nofail(group, new_domain);
+}
+
+static 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)
+ return ret;
+ dev->iommu->attach_deferred = 0;
+ trace_attach_device_to_domain(dev);
+ return 0;
+}
+
+/**
+ * iommu_attach_device - Attach an IOMMU domain to a device
+ * @domain: IOMMU domain to attach
+ * @dev: Device that will be attached
+ *
+ * Returns 0 on success and error code on failure
+ *
+ * Note that EINVAL can be treated as a soft failure, indicating
+ * that certain configuration of the domain is incompatible with
+ * the device. In this case attaching a different domain to the
+ * device may succeed.
+ */
+int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
+{
+ struct iommu_group *group;
+ int ret;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return -ENODEV;
+
+ /*
+ * Lock the group to make sure the device-count doesn't
+ * change while we are attaching
+ */
+ mutex_lock(&group->mutex);
+ ret = -EINVAL;
+ if (list_count_nodes(&group->devices) != 1)
+ goto out_unlock;
+
+ ret = __iommu_attach_group(domain, group);
+
+out_unlock:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_attach_device);
+
+int iommu_deferred_attach(struct device *dev, struct iommu_domain *domain)
+{
+ if (dev->iommu && dev->iommu->attach_deferred)
+ return __iommu_attach_device(domain, dev);
+
+ return 0;
+}
+
+void iommu_detach_device(struct iommu_domain *domain, struct device *dev)
+{
+ struct iommu_group *group;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return;
+
+ mutex_lock(&group->mutex);
+ if (WARN_ON(domain != group->domain) ||
+ WARN_ON(list_count_nodes(&group->devices) != 1))
+ goto out_unlock;
+ __iommu_group_set_core_domain(group);
+
+out_unlock:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+}
+EXPORT_SYMBOL_GPL(iommu_detach_device);
+
+struct iommu_domain *iommu_get_domain_for_dev(struct device *dev)
+{
+ struct iommu_domain *domain;
+ struct iommu_group *group;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return NULL;
+
+ domain = group->domain;
+
+ iommu_group_put(group);
+
+ return domain;
+}
+EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev);
+
+/*
+ * For IOMMU_DOMAIN_DMA implementations which already provide their own
+ * guarantees that the group and its default domain are valid and correct.
+ */
+struct iommu_domain *iommu_get_dma_domain(struct device *dev)
+{
+ return dev->iommu_group->default_domain;
+}
+
+static int __iommu_attach_group(struct iommu_domain *domain,
+ struct iommu_group *group)
+{
+ if (group->domain && group->domain != group->default_domain &&
+ group->domain != group->blocking_domain)
+ return -EBUSY;
+
+ return __iommu_group_set_domain(group, domain);
+}
+
+/**
+ * iommu_attach_group - Attach an IOMMU domain to an IOMMU group
+ * @domain: IOMMU domain to attach
+ * @group: IOMMU group that will be attached
+ *
+ * Returns 0 on success and error code on failure
+ *
+ * Note that EINVAL can be treated as a soft failure, indicating
+ * that certain configuration of the domain is incompatible with
+ * the group. In this case attaching a different domain to the
+ * group may succeed.
+ */
+int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
+{
+ int ret;
+
+ mutex_lock(&group->mutex);
+ ret = __iommu_attach_group(domain, group);
+ mutex_unlock(&group->mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_attach_group);
+
+/**
+ * iommu_group_replace_domain - replace the domain that a group is attached to
+ * @new_domain: new IOMMU domain to replace with
+ * @group: IOMMU group that will be attached to the new domain
+ *
+ * This API allows the group to switch domains without being forced to go to
+ * the blocking domain in-between.
+ *
+ * If the currently attached domain is a core domain (e.g. a default_domain),
+ * it will act just like the iommu_attach_group().
+ */
+int iommu_group_replace_domain(struct iommu_group *group,
+ struct iommu_domain *new_domain)
+{
+ int ret;
+
+ if (!new_domain)
+ return -EINVAL;
+
+ mutex_lock(&group->mutex);
+ ret = __iommu_group_set_domain(group, new_domain);
+ mutex_unlock(&group->mutex);
+ return ret;
+}
+EXPORT_SYMBOL_NS_GPL(iommu_group_replace_domain, IOMMUFD_INTERNAL);
+
+static int __iommu_device_set_domain(struct iommu_group *group,
+ struct device *dev,
+ struct iommu_domain *new_domain,
+ unsigned int flags)
+{
+ int ret;
+
+ /*
+ * If the device requires IOMMU_RESV_DIRECT then we cannot allow
+ * the blocking domain to be attached as it does not contain the
+ * required 1:1 mapping. This test effectively excludes the device
+ * being used with iommu_group_claim_dma_owner() which will block
+ * vfio and iommufd as well.
+ */
+ if (dev->iommu->require_direct &&
+ (new_domain->type == IOMMU_DOMAIN_BLOCKED ||
+ new_domain == group->blocking_domain)) {
+ dev_warn(dev,
+ "Firmware has requested this device have a 1:1 IOMMU mapping, rejecting configuring the device without a 1:1 mapping. Contact your platform vendor.\n");
+ return -EINVAL;
+ }
+
+ if (dev->iommu->attach_deferred) {
+ if (new_domain == group->default_domain)
+ return 0;
+ dev->iommu->attach_deferred = 0;
+ }
+
+ ret = __iommu_attach_device(new_domain, dev);
+ if (ret) {
+ /*
+ * If we have a blocking domain then try to attach that in hopes
+ * of avoiding a UAF. Modern drivers should implement blocking
+ * domains as global statics that cannot fail.
+ */
+ if ((flags & IOMMU_SET_DOMAIN_MUST_SUCCEED) &&
+ group->blocking_domain &&
+ group->blocking_domain != new_domain)
+ __iommu_attach_device(group->blocking_domain, dev);
+ return ret;
+ }
+ return 0;
+}
+
+/*
+ * If 0 is returned the group's domain is new_domain. If an error is returned
+ * then the group's domain will be set back to the existing domain unless
+ * IOMMU_SET_DOMAIN_MUST_SUCCEED, otherwise an error is returned and the group's
+ * domains is left inconsistent. This is a driver bug to fail attach with a
+ * previously good domain. We try to avoid a kernel UAF because of this.
+ *
+ * IOMMU groups are really the natural 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_set_domain_internal(struct iommu_group *group,
+ struct iommu_domain *new_domain,
+ unsigned int flags)
+{
+ struct group_device *last_gdev;
+ struct group_device *gdev;
+ int result;
+ int ret;
+
+ lockdep_assert_held(&group->mutex);
+
+ if (group->domain == new_domain)
+ return 0;
+
+ /*
+ * New drivers should support default domains, so set_platform_dma()
+ * op will never be called. Otherwise the NULL domain represents some
+ * platform specific behavior.
+ */
+ if (!new_domain) {
+ for_each_group_device(group, gdev) {
+ const struct iommu_ops *ops = dev_iommu_ops(gdev->dev);
+
+ if (!WARN_ON(!ops->set_platform_dma_ops))
+ ops->set_platform_dma_ops(gdev->dev);
+ }
+ group->domain = NULL;
+ return 0;
+ }
+
+ /*
+ * Changing the domain is done by calling attach_dev() on the new
+ * domain. This switch does not have to be atomic and DMA can be
+ * discarded during the transition. DMA must only be able to access
+ * either new_domain or group->domain, never something else.
+ */
+ result = 0;
+ for_each_group_device(group, gdev) {
+ ret = __iommu_device_set_domain(group, gdev->dev, new_domain,
+ flags);
+ if (ret) {
+ result = ret;
+ /*
+ * Keep trying the other devices in the group. If a
+ * driver fails attach to an otherwise good domain, and
+ * does not support blocking domains, it should at least
+ * drop its reference on the current domain so we don't
+ * UAF.
+ */
+ if (flags & IOMMU_SET_DOMAIN_MUST_SUCCEED)
+ continue;
+ goto err_revert;
+ }
+ }
+ group->domain = new_domain;
+ return result;
+
+err_revert:
+ /*
+ * This is called in error unwind paths. A well behaved driver should
+ * always allow us to attach to a domain that was already attached.
+ */
+ last_gdev = gdev;
+ for_each_group_device(group, gdev) {
+ const struct iommu_ops *ops = dev_iommu_ops(gdev->dev);
+
+ /*
+ * If set_platform_dma_ops is not present a NULL domain can
+ * happen only for first probe, in which case we leave
+ * group->domain as NULL and let release clean everything up.
+ */
+ if (group->domain)
+ WARN_ON(__iommu_device_set_domain(
+ group, gdev->dev, group->domain,
+ IOMMU_SET_DOMAIN_MUST_SUCCEED));
+ else if (ops->set_platform_dma_ops)
+ ops->set_platform_dma_ops(gdev->dev);
+ if (gdev == last_gdev)
+ break;
+ }
+ return ret;
+}
+
+void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group)
+{
+ mutex_lock(&group->mutex);
+ __iommu_group_set_core_domain(group);
+ mutex_unlock(&group->mutex);
+}
+EXPORT_SYMBOL_GPL(iommu_detach_group);
+
+phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
+{
+ if (domain->type == IOMMU_DOMAIN_IDENTITY)
+ return iova;
+
+ if (domain->type == IOMMU_DOMAIN_BLOCKED)
+ 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 iova,
+ phys_addr_t paddr, size_t size, size_t *count)
+{
+ unsigned int pgsize_idx, pgsize_idx_next;
+ unsigned long pgsizes;
+ size_t offset, pgsize, pgsize_next;
+ unsigned long addr_merge = paddr | iova;
+
+ /* Page sizes supported by the hardware and small enough for @size */
+ pgsizes = domain->pgsize_bitmap & GENMASK(__fls(size), 0);
+
+ /* Constrain the page sizes further based on the maximum alignment */
+ if (likely(addr_merge))
+ pgsizes &= GENMASK(__ffs(addr_merge), 0);
+
+ /* Make sure we have at least one suitable page size */
+ BUG_ON(!pgsizes);
+
+ /* Pick the biggest page size remaining */
+ pgsize_idx = __fls(pgsizes);
+ pgsize = BIT(pgsize_idx);
+ if (!count)
+ return pgsize;
+
+ /* Find the next biggest support page size, if it exists */
+ pgsizes = domain->pgsize_bitmap & ~GENMASK(pgsize_idx, 0);
+ if (!pgsizes)
+ goto out_set_count;
+
+ pgsize_idx_next = __ffs(pgsizes);
+ pgsize_next = BIT(pgsize_idx_next);
+
+ /*
+ * There's no point trying a bigger page size unless the virtual
+ * and physical addresses are similarly offset within the larger page.
+ */
+ if ((iova ^ paddr) & (pgsize_next - 1))
+ goto out_set_count;
+
+ /* Calculate the offset to the next page size alignment boundary */
+ offset = pgsize_next - (addr_merge & (pgsize_next - 1));
+
+ /*
+ * If size is big enough to accommodate the larger page, reduce
+ * the number of smaller pages.
+ */
+ if (offset + pgsize_next <= size)
+ size = offset;
+
+out_set_count:
+ *count = size >> pgsize_idx;
+ return pgsize;
+}
+
+static int __iommu_map_pages(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot,
+ gfp_t gfp, size_t *mapped)
+{
+ const struct iommu_domain_ops *ops = domain->ops;
+ size_t pgsize, count;
+ int ret;
+
+ pgsize = iommu_pgsize(domain, iova, paddr, size, &count);
+
+ pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx count %zu\n",
+ iova, &paddr, pgsize, count);
+
+ if (ops->map_pages) {
+ ret = ops->map_pages(domain, iova, paddr, pgsize, count, prot,
+ gfp, mapped);
+ } else {
+ ret = ops->map(domain, iova, paddr, pgsize, prot, gfp);
+ *mapped = ret ? 0 : pgsize;
+ }
+
+ return ret;
+}
+
+static int __iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+{
+ const struct iommu_domain_ops *ops = domain->ops;
+ unsigned long orig_iova = iova;
+ unsigned int min_pagesz;
+ size_t orig_size = size;
+ phys_addr_t orig_paddr = paddr;
+ int ret = 0;
+
+ if (unlikely(!(ops->map || ops->map_pages) ||
+ domain->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->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 mapped = 0;
+
+ ret = __iommu_map_pages(domain, iova, paddr, size, prot, gfp,
+ &mapped);
+ /*
+ * Some pages may have been mapped, even if an error occurred,
+ * so we should account for those so they can be unmapped.
+ */
+ size -= mapped;
+
+ if (ret)
+ break;
+
+ iova += mapped;
+ paddr += mapped;
+ }
+
+ /* unroll mapping in case something went wrong */
+ if (ret)
+ iommu_unmap(domain, orig_iova, orig_size - size);
+ else
+ trace_map(orig_iova, orig_paddr, orig_size);
+
+ return ret;
+}
+
+int iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+{
+ const struct iommu_domain_ops *ops = domain->ops;
+ int ret;
+
+ might_sleep_if(gfpflags_allow_blocking(gfp));
+
+ /* Discourage passing strange GFP flags */
+ if (WARN_ON_ONCE(gfp & (__GFP_COMP | __GFP_DMA | __GFP_DMA32 |
+ __GFP_HIGHMEM)))
+ return -EINVAL;
+
+ ret = __iommu_map(domain, iova, paddr, size, prot, gfp);
+ if (ret == 0 && ops->iotlb_sync_map)
+ ops->iotlb_sync_map(domain, iova, size);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_map);
+
+static size_t __iommu_unmap_pages(struct iommu_domain *domain,
+ unsigned long iova, size_t size,
+ struct iommu_iotlb_gather *iotlb_gather)
+{
+ const struct iommu_domain_ops *ops = domain->ops;
+ size_t pgsize, count;
+
+ pgsize = iommu_pgsize(domain, iova, iova, size, &count);
+ return ops->unmap_pages ?
+ ops->unmap_pages(domain, iova, pgsize, count, iotlb_gather) :
+ ops->unmap(domain, iova, pgsize, iotlb_gather);
+}
+
+static size_t __iommu_unmap(struct iommu_domain *domain,
+ unsigned long iova, size_t size,
+ struct iommu_iotlb_gather *iotlb_gather)
+{
+ const struct iommu_domain_ops *ops = domain->ops;
+ size_t unmapped_page, unmapped = 0;
+ unsigned long orig_iova = iova;
+ unsigned int min_pagesz;
+
+ if (unlikely(!(ops->unmap || ops->unmap_pages) ||
+ domain->pgsize_bitmap == 0UL))
+ return 0;
+
+ if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
+ return 0;
+
+ /* find out the minimum page size supported */
+ min_pagesz = 1 << __ffs(domain->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 0;
+ }
+
+ 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) {
+ unmapped_page = __iommu_unmap_pages(domain, iova,
+ size - unmapped,
+ iotlb_gather);
+ 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;
+}
+
+size_t iommu_unmap(struct iommu_domain *domain,
+ unsigned long iova, size_t size)
+{
+ struct iommu_iotlb_gather iotlb_gather;
+ size_t ret;
+
+ iommu_iotlb_gather_init(&iotlb_gather);
+ ret = __iommu_unmap(domain, iova, size, &iotlb_gather);
+ iommu_iotlb_sync(domain, &iotlb_gather);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_unmap);
+
+size_t iommu_unmap_fast(struct iommu_domain *domain,
+ unsigned long iova, size_t size,
+ struct iommu_iotlb_gather *iotlb_gather)
+{
+ return __iommu_unmap(domain, iova, size, iotlb_gather);
+}
+EXPORT_SYMBOL_GPL(iommu_unmap_fast);
+
+ssize_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
+ struct scatterlist *sg, unsigned int nents, int prot,
+ gfp_t gfp)
+{
+ const struct iommu_domain_ops *ops = domain->ops;
+ size_t len = 0, mapped = 0;
+ phys_addr_t start;
+ unsigned int i = 0;
+ int ret;
+
+ might_sleep_if(gfpflags_allow_blocking(gfp));
+
+ /* Discourage passing strange GFP flags */
+ if (WARN_ON_ONCE(gfp & (__GFP_COMP | __GFP_DMA | __GFP_DMA32 |
+ __GFP_HIGHMEM)))
+ return -EINVAL;
+
+ while (i <= nents) {
+ phys_addr_t s_phys = sg_phys(sg);
+
+ if (len && s_phys != start + len) {
+ ret = __iommu_map(domain, iova + mapped, start,
+ len, prot, gfp);
+
+ if (ret)
+ goto out_err;
+
+ mapped += len;
+ len = 0;
+ }
+
+ if (sg_dma_is_bus_address(sg))
+ goto next;
+
+ if (len) {
+ len += sg->length;
+ } else {
+ len = sg->length;
+ start = s_phys;
+ }
+
+next:
+ if (++i < nents)
+ sg = sg_next(sg);
+ }
+
+ if (ops->iotlb_sync_map)
+ ops->iotlb_sync_map(domain, iova, mapped);
+ return mapped;
+
+out_err:
+ /* undo mappings already done */
+ iommu_unmap(domain, iova, mapped);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_map_sg);
+
+/**
+ * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
+ * @domain: the iommu domain where the fault has happened
+ * @dev: the device where the fault has happened
+ * @iova: the faulting address
+ * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
+ *
+ * This function should be called by the low-level IOMMU implementations
+ * whenever IOMMU faults happen, to allow high-level users, that are
+ * interested in such events, to know about them.
+ *
+ * This event may be useful for several possible use cases:
+ * - mere logging of the event
+ * - dynamic TLB/PTE loading
+ * - if restarting of the faulting device is required
+ *
+ * Returns 0 on success and an appropriate error code otherwise (if dynamic
+ * PTE/TLB loading will one day be supported, implementations will be able
+ * to tell whether it succeeded or not according to this return value).
+ *
+ * Specifically, -ENOSYS is returned if a fault handler isn't installed
+ * (though fault handlers can also return -ENOSYS, in case they want to
+ * elicit the default behavior of the IOMMU drivers).
+ */
+int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
+ unsigned long iova, int flags)
+{
+ int ret = -ENOSYS;
+
+ /*
+ * if upper layers showed interest and installed a fault handler,
+ * invoke it.
+ */
+ if (domain->handler)
+ ret = domain->handler(domain, dev, iova, flags,
+ domain->handler_token);
+
+ trace_io_page_fault(dev, iova, flags);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(report_iommu_fault);
+
+static int __init iommu_init(void)
+{
+ iommu_group_kset = kset_create_and_add("iommu_groups",
+ NULL, kernel_kobj);
+ BUG_ON(!iommu_group_kset);
+
+ iommu_debugfs_setup();
+
+ return 0;
+}
+core_initcall(iommu_init);
+
+int iommu_enable_nesting(struct iommu_domain *domain)
+{
+ if (domain->type != IOMMU_DOMAIN_UNMANAGED)
+ return -EINVAL;
+ if (!domain->ops->enable_nesting)
+ return -EINVAL;
+ return domain->ops->enable_nesting(domain);
+}
+EXPORT_SYMBOL_GPL(iommu_enable_nesting);
+
+int iommu_set_pgtable_quirks(struct iommu_domain *domain,
+ unsigned long quirk)
+{
+ if (domain->type != IOMMU_DOMAIN_UNMANAGED)
+ return -EINVAL;
+ if (!domain->ops->set_pgtable_quirks)
+ return -EINVAL;
+ return domain->ops->set_pgtable_quirks(domain, quirk);
+}
+EXPORT_SYMBOL_GPL(iommu_set_pgtable_quirks);
+
+/**
+ * iommu_get_resv_regions - get reserved regions
+ * @dev: device for which to get reserved regions
+ * @list: reserved region list for device
+ *
+ * This returns a list of reserved IOVA regions specific to this device.
+ * A domain user should not map IOVA in these ranges.
+ */
+void iommu_get_resv_regions(struct device *dev, struct list_head *list)
+{
+ const struct iommu_ops *ops = dev_iommu_ops(dev);
+
+ if (ops->get_resv_regions)
+ ops->get_resv_regions(dev, list);
+}
+EXPORT_SYMBOL_GPL(iommu_get_resv_regions);
+
+/**
+ * iommu_put_resv_regions - release reserved regions
+ * @dev: device for which to free reserved regions
+ * @list: reserved region list for device
+ *
+ * This releases a reserved region list acquired by iommu_get_resv_regions().
+ */
+void iommu_put_resv_regions(struct device *dev, struct list_head *list)
+{
+ struct iommu_resv_region *entry, *next;
+
+ list_for_each_entry_safe(entry, next, list, list) {
+ if (entry->free)
+ entry->free(dev, entry);
+ else
+ kfree(entry);
+ }
+}
+EXPORT_SYMBOL(iommu_put_resv_regions);
+
+struct iommu_resv_region *iommu_alloc_resv_region(phys_addr_t start,
+ size_t length, int prot,
+ enum iommu_resv_type type,
+ gfp_t gfp)
+{
+ struct iommu_resv_region *region;
+
+ region = kzalloc(sizeof(*region), gfp);
+ if (!region)
+ return NULL;
+
+ INIT_LIST_HEAD(&region->list);
+ region->start = start;
+ region->length = length;
+ region->prot = prot;
+ region->type = type;
+ return region;
+}
+EXPORT_SYMBOL_GPL(iommu_alloc_resv_region);
+
+void iommu_set_default_passthrough(bool cmd_line)
+{
+ if (cmd_line)
+ iommu_cmd_line |= IOMMU_CMD_LINE_DMA_API;
+ iommu_def_domain_type = IOMMU_DOMAIN_IDENTITY;
+}
+
+void iommu_set_default_translated(bool cmd_line)
+{
+ if (cmd_line)
+ iommu_cmd_line |= IOMMU_CMD_LINE_DMA_API;
+ iommu_def_domain_type = IOMMU_DOMAIN_DMA;
+}
+
+bool iommu_default_passthrough(void)
+{
+ return iommu_def_domain_type == IOMMU_DOMAIN_IDENTITY;
+}
+EXPORT_SYMBOL_GPL(iommu_default_passthrough);
+
+const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
+{
+ const struct iommu_ops *ops = NULL;
+ struct iommu_device *iommu;
+
+ spin_lock(&iommu_device_lock);
+ list_for_each_entry(iommu, &iommu_device_list, list)
+ if (iommu->fwnode == fwnode) {
+ ops = iommu->ops;
+ break;
+ }
+ spin_unlock(&iommu_device_lock);
+ return ops;
+}
+
+int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
+ const struct iommu_ops *ops)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+ if (fwspec)
+ return ops == fwspec->ops ? 0 : -EINVAL;
+
+ if (!dev_iommu_get(dev))
+ return -ENOMEM;
+
+ /* Preallocate for the overwhelmingly common case of 1 ID */
+ fwspec = kzalloc(struct_size(fwspec, ids, 1), GFP_KERNEL);
+ if (!fwspec)
+ return -ENOMEM;
+
+ of_node_get(to_of_node(iommu_fwnode));
+ fwspec->iommu_fwnode = iommu_fwnode;
+ fwspec->ops = ops;
+ dev_iommu_fwspec_set(dev, fwspec);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_fwspec_init);
+
+void iommu_fwspec_free(struct device *dev)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+ if (fwspec) {
+ fwnode_handle_put(fwspec->iommu_fwnode);
+ kfree(fwspec);
+ dev_iommu_fwspec_set(dev, NULL);
+ }
+}
+EXPORT_SYMBOL_GPL(iommu_fwspec_free);
+
+int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
+{
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+ int i, new_num;
+
+ if (!fwspec)
+ return -EINVAL;
+
+ new_num = fwspec->num_ids + num_ids;
+ if (new_num > 1) {
+ fwspec = krealloc(fwspec, struct_size(fwspec, ids, new_num),
+ GFP_KERNEL);
+ if (!fwspec)
+ return -ENOMEM;
+
+ dev_iommu_fwspec_set(dev, fwspec);
+ }
+
+ for (i = 0; i < num_ids; i++)
+ fwspec->ids[fwspec->num_ids + i] = ids[i];
+
+ fwspec->num_ids = new_num;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids);
+
+/*
+ * Per device IOMMU features.
+ */
+int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+ if (dev->iommu && dev->iommu->iommu_dev) {
+ const struct iommu_ops *ops = dev->iommu->iommu_dev->ops;
+
+ if (ops->dev_enable_feat)
+ return ops->dev_enable_feat(dev, feat);
+ }
+
+ return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_enable_feature);
+
+/*
+ * The device drivers should do the necessary cleanups before calling this.
+ */
+int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+ if (dev->iommu && dev->iommu->iommu_dev) {
+ const struct iommu_ops *ops = dev->iommu->iommu_dev->ops;
+
+ if (ops->dev_disable_feat)
+ return ops->dev_disable_feat(dev, feat);
+ }
+
+ return -EBUSY;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_disable_feature);
+
+/**
+ * iommu_setup_default_domain - Set the default_domain for the group
+ * @group: Group to change
+ * @target_type: Domain type to set as the default_domain
+ *
+ * Allocate a default domain and set it as the current domain on the group. If
+ * the group already has a default domain it will be changed to the target_type.
+ * When target_type is 0 the default domain is selected based on driver and
+ * system preferences.
+ */
+static int iommu_setup_default_domain(struct iommu_group *group,
+ int target_type)
+{
+ struct iommu_domain *old_dom = group->default_domain;
+ struct group_device *gdev;
+ struct iommu_domain *dom;
+ bool direct_failed;
+ int req_type;
+ int ret;
+
+ lockdep_assert_held(&group->mutex);
+
+ req_type = iommu_get_default_domain_type(group, target_type);
+ if (req_type < 0)
+ return -EINVAL;
+
+ /*
+ * There are still some drivers which don't support default domains, so
+ * we ignore the failure and leave group->default_domain NULL.
+ *
+ * We assume that the iommu driver starts up the device in
+ * 'set_platform_dma_ops' mode if it does not support default domains.
+ */
+ dom = iommu_group_alloc_default_domain(group, req_type);
+ if (!dom) {
+ /* Once in default_domain mode we never leave */
+ if (group->default_domain)
+ return -ENODEV;
+ group->default_domain = NULL;
+ return 0;
+ }
+
+ if (group->default_domain == dom)
+ return 0;
+
+ /*
+ * IOMMU_RESV_DIRECT and IOMMU_RESV_DIRECT_RELAXABLE regions must be
+ * mapped before their device is attached, in order to guarantee
+ * continuity with any FW activity
+ */
+ direct_failed = false;
+ for_each_group_device(group, gdev) {
+ if (iommu_create_device_direct_mappings(dom, gdev->dev)) {
+ direct_failed = true;
+ dev_warn_once(
+ gdev->dev->iommu->iommu_dev->dev,
+ "IOMMU driver was not able to establish FW requested direct mapping.");
+ }
+ }
+
+ /* We must set default_domain early for __iommu_device_set_domain */
+ group->default_domain = dom;
+ if (!group->domain) {
+ /*
+ * Drivers are not allowed to fail the first domain attach.
+ * The only way to recover from this is to fail attaching the
+ * iommu driver and call ops->release_device. Put the domain
+ * in group->default_domain so it is freed after.
+ */
+ ret = __iommu_group_set_domain_internal(
+ group, dom, IOMMU_SET_DOMAIN_MUST_SUCCEED);
+ if (WARN_ON(ret))
+ goto out_free_old;
+ } else {
+ ret = __iommu_group_set_domain(group, dom);
+ if (ret)
+ goto err_restore_def_domain;
+ }
+
+ /*
+ * Drivers are supposed to allow mappings to be installed in a domain
+ * before device attachment, but some don't. Hack around this defect by
+ * trying again after attaching. If this happens it means the device
+ * will not continuously have the IOMMU_RESV_DIRECT map.
+ */
+ if (direct_failed) {
+ for_each_group_device(group, gdev) {
+ ret = iommu_create_device_direct_mappings(dom, gdev->dev);
+ if (ret)
+ goto err_restore_domain;
+ }
+ }
+
+out_free_old:
+ if (old_dom)
+ iommu_domain_free(old_dom);
+ return ret;
+
+err_restore_domain:
+ if (old_dom)
+ __iommu_group_set_domain_internal(
+ group, old_dom, IOMMU_SET_DOMAIN_MUST_SUCCEED);
+err_restore_def_domain:
+ if (old_dom) {
+ iommu_domain_free(dom);
+ group->default_domain = old_dom;
+ }
+ return ret;
+}
+
+/*
+ * Changing the default domain through sysfs requires the users to unbind the
+ * drivers from the devices in the iommu group, except for a DMA -> DMA-FQ
+ * transition. Return failure if this isn't met.
+ *
+ * We need to consider the race between this and the device release path.
+ * group->mutex is used here to guarantee that the device release path
+ * will not be entered at the same time.
+ */
+static ssize_t iommu_group_store_type(struct iommu_group *group,
+ const char *buf, size_t count)
+{
+ struct group_device *gdev;
+ int ret, req_type;
+
+ if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
+ return -EACCES;
+
+ if (WARN_ON(!group) || !group->default_domain)
+ return -EINVAL;
+
+ if (sysfs_streq(buf, "identity"))
+ req_type = IOMMU_DOMAIN_IDENTITY;
+ else if (sysfs_streq(buf, "DMA"))
+ req_type = IOMMU_DOMAIN_DMA;
+ else if (sysfs_streq(buf, "DMA-FQ"))
+ req_type = IOMMU_DOMAIN_DMA_FQ;
+ else if (sysfs_streq(buf, "auto"))
+ req_type = 0;
+ else
+ return -EINVAL;
+
+ mutex_lock(&group->mutex);
+ /* We can bring up a flush queue without tearing down the domain. */
+ if (req_type == IOMMU_DOMAIN_DMA_FQ &&
+ group->default_domain->type == IOMMU_DOMAIN_DMA) {
+ ret = iommu_dma_init_fq(group->default_domain);
+ if (ret)
+ goto out_unlock;
+
+ group->default_domain->type = IOMMU_DOMAIN_DMA_FQ;
+ ret = count;
+ goto out_unlock;
+ }
+
+ /* Otherwise, ensure that device exists and no driver is bound. */
+ if (list_empty(&group->devices) || group->owner_cnt) {
+ ret = -EPERM;
+ goto out_unlock;
+ }
+
+ ret = iommu_setup_default_domain(group, req_type);
+ if (ret)
+ goto out_unlock;
+
+ /*
+ * Release the mutex here because ops->probe_finalize() call-back of
+ * some vendor IOMMU drivers calls arm_iommu_attach_device() which
+ * in-turn might call back into IOMMU core code, where it tries to take
+ * group->mutex, resulting in a deadlock.
+ */
+ mutex_unlock(&group->mutex);
+
+ /* Make sure dma_ops is appropriatley set */
+ for_each_group_device(group, gdev)
+ iommu_group_do_probe_finalize(gdev->dev);
+ return count;
+
+out_unlock:
+ mutex_unlock(&group->mutex);
+ return ret ?: count;
+}
+
+static bool iommu_is_default_domain(struct iommu_group *group)
+{
+ if (group->domain == group->default_domain)
+ return true;
+
+ /*
+ * If the default domain was set to identity and it is still an identity
+ * domain then we consider this a pass. This happens because of
+ * amd_iommu_init_device() replacing the default idenytity domain with an
+ * identity domain that has a different configuration for AMDGPU.
+ */
+ if (group->default_domain &&
+ group->default_domain->type == IOMMU_DOMAIN_IDENTITY &&
+ group->domain && group->domain->type == IOMMU_DOMAIN_IDENTITY)
+ return true;
+ return false;
+}
+
+/**
+ * iommu_device_use_default_domain() - Device driver wants to handle device
+ * DMA through the kernel DMA API.
+ * @dev: The device.
+ *
+ * The device driver about to bind @dev wants to do DMA through the kernel
+ * DMA API. Return 0 if it is allowed, otherwise an error.
+ */
+int iommu_device_use_default_domain(struct device *dev)
+{
+ struct iommu_group *group = iommu_group_get(dev);
+ int ret = 0;
+
+ if (!group)
+ return 0;
+
+ mutex_lock(&group->mutex);
+ if (group->owner_cnt) {
+ if (group->owner || !iommu_is_default_domain(group) ||
+ !xa_empty(&group->pasid_array)) {
+ ret = -EBUSY;
+ goto unlock_out;
+ }
+ }
+
+ group->owner_cnt++;
+
+unlock_out:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+
+ return ret;
+}
+
+/**
+ * iommu_device_unuse_default_domain() - Device driver stops handling device
+ * DMA through the kernel DMA API.
+ * @dev: The device.
+ *
+ * The device driver doesn't want to do DMA through kernel DMA API anymore.
+ * It must be called after iommu_device_use_default_domain().
+ */
+void iommu_device_unuse_default_domain(struct device *dev)
+{
+ struct iommu_group *group = iommu_group_get(dev);
+
+ if (!group)
+ return;
+
+ mutex_lock(&group->mutex);
+ if (!WARN_ON(!group->owner_cnt || !xa_empty(&group->pasid_array)))
+ group->owner_cnt--;
+
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+}
+
+static int __iommu_group_alloc_blocking_domain(struct iommu_group *group)
+{
+ struct group_device *dev =
+ list_first_entry(&group->devices, struct group_device, list);
+
+ if (group->blocking_domain)
+ return 0;
+
+ group->blocking_domain =
+ __iommu_domain_alloc(dev->dev->bus, IOMMU_DOMAIN_BLOCKED);
+ if (!group->blocking_domain) {
+ /*
+ * For drivers that do not yet understand IOMMU_DOMAIN_BLOCKED
+ * create an empty domain instead.
+ */
+ group->blocking_domain = __iommu_domain_alloc(
+ dev->dev->bus, IOMMU_DOMAIN_UNMANAGED);
+ if (!group->blocking_domain)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int __iommu_take_dma_ownership(struct iommu_group *group, void *owner)
+{
+ int ret;
+
+ if ((group->domain && group->domain != group->default_domain) ||
+ !xa_empty(&group->pasid_array))
+ return -EBUSY;
+
+ ret = __iommu_group_alloc_blocking_domain(group);
+ if (ret)
+ return ret;
+ ret = __iommu_group_set_domain(group, group->blocking_domain);
+ if (ret)
+ return ret;
+
+ group->owner = owner;
+ group->owner_cnt++;
+ return 0;
+}
+
+/**
+ * iommu_group_claim_dma_owner() - Set DMA ownership of a group
+ * @group: The group.
+ * @owner: Caller specified pointer. Used for exclusive ownership.
+ *
+ * This is to support backward compatibility for vfio which manages the dma
+ * ownership in iommu_group level. New invocations on this interface should be
+ * prohibited. Only a single owner may exist for a group.
+ */
+int iommu_group_claim_dma_owner(struct iommu_group *group, void *owner)
+{
+ int ret = 0;
+
+ if (WARN_ON(!owner))
+ return -EINVAL;
+
+ mutex_lock(&group->mutex);
+ if (group->owner_cnt) {
+ ret = -EPERM;
+ goto unlock_out;
+ }
+
+ ret = __iommu_take_dma_ownership(group, owner);
+unlock_out:
+ mutex_unlock(&group->mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_group_claim_dma_owner);
+
+/**
+ * iommu_device_claim_dma_owner() - Set DMA ownership of a device
+ * @dev: The device.
+ * @owner: Caller specified pointer. Used for exclusive ownership.
+ *
+ * Claim the DMA ownership of a device. Multiple devices in the same group may
+ * concurrently claim ownership if they present the same owner value. Returns 0
+ * on success and error code on failure
+ */
+int iommu_device_claim_dma_owner(struct device *dev, void *owner)
+{
+ struct iommu_group *group;
+ int ret = 0;
+
+ if (WARN_ON(!owner))
+ return -EINVAL;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return -ENODEV;
+
+ mutex_lock(&group->mutex);
+ if (group->owner_cnt) {
+ if (group->owner != owner) {
+ ret = -EPERM;
+ goto unlock_out;
+ }
+ group->owner_cnt++;
+ goto unlock_out;
+ }
+
+ ret = __iommu_take_dma_ownership(group, owner);
+unlock_out:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_device_claim_dma_owner);
+
+static void __iommu_release_dma_ownership(struct iommu_group *group)
+{
+ if (WARN_ON(!group->owner_cnt || !group->owner ||
+ !xa_empty(&group->pasid_array)))
+ return;
+
+ group->owner_cnt = 0;
+ group->owner = NULL;
+ __iommu_group_set_domain_nofail(group, group->default_domain);
+}
+
+/**
+ * iommu_group_release_dma_owner() - Release DMA ownership of a group
+ * @group: The group
+ *
+ * Release the DMA ownership claimed by iommu_group_claim_dma_owner().
+ */
+void iommu_group_release_dma_owner(struct iommu_group *group)
+{
+ mutex_lock(&group->mutex);
+ __iommu_release_dma_ownership(group);
+ mutex_unlock(&group->mutex);
+}
+EXPORT_SYMBOL_GPL(iommu_group_release_dma_owner);
+
+/**
+ * iommu_device_release_dma_owner() - Release DMA ownership of a device
+ * @dev: The device.
+ *
+ * Release the DMA ownership claimed by iommu_device_claim_dma_owner().
+ */
+void iommu_device_release_dma_owner(struct device *dev)
+{
+ struct iommu_group *group = iommu_group_get(dev);
+
+ mutex_lock(&group->mutex);
+ if (group->owner_cnt > 1)
+ group->owner_cnt--;
+ else
+ __iommu_release_dma_ownership(group);
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+}
+EXPORT_SYMBOL_GPL(iommu_device_release_dma_owner);
+
+/**
+ * iommu_group_dma_owner_claimed() - Query group dma ownership status
+ * @group: The group.
+ *
+ * This provides status query on a given group. It is racy and only for
+ * non-binding status reporting.
+ */
+bool iommu_group_dma_owner_claimed(struct iommu_group *group)
+{
+ unsigned int user;
+
+ mutex_lock(&group->mutex);
+ user = group->owner_cnt;
+ mutex_unlock(&group->mutex);
+
+ return user;
+}
+EXPORT_SYMBOL_GPL(iommu_group_dma_owner_claimed);
+
+static int __iommu_set_group_pasid(struct iommu_domain *domain,
+ struct iommu_group *group, ioasid_t pasid)
+{
+ struct group_device *device;
+ int ret = 0;
+
+ for_each_group_device(group, device) {
+ ret = domain->ops->set_dev_pasid(domain, device->dev, pasid);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+static void __iommu_remove_group_pasid(struct iommu_group *group,
+ ioasid_t pasid)
+{
+ struct group_device *device;
+ const struct iommu_ops *ops;
+
+ for_each_group_device(group, device) {
+ ops = dev_iommu_ops(device->dev);
+ ops->remove_dev_pasid(device->dev, pasid);
+ }
+}
+
+/*
+ * iommu_attach_device_pasid() - Attach a domain to pasid of device
+ * @domain: the iommu domain.
+ * @dev: the attached device.
+ * @pasid: the pasid of the device.
+ *
+ * Return: 0 on success, or an error.
+ */
+int iommu_attach_device_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t pasid)
+{
+ struct iommu_group *group;
+ void *curr;
+ int ret;
+
+ if (!domain->ops->set_dev_pasid)
+ return -EOPNOTSUPP;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return -ENODEV;
+
+ mutex_lock(&group->mutex);
+ curr = xa_cmpxchg(&group->pasid_array, pasid, NULL, domain, GFP_KERNEL);
+ if (curr) {
+ ret = xa_err(curr) ? : -EBUSY;
+ goto out_unlock;
+ }
+
+ ret = __iommu_set_group_pasid(domain, group, pasid);
+ if (ret) {
+ __iommu_remove_group_pasid(group, pasid);
+ xa_erase(&group->pasid_array, pasid);
+ }
+out_unlock:
+ mutex_unlock(&group->mutex);
+ iommu_group_put(group);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_attach_device_pasid);
+
+/*
+ * iommu_detach_device_pasid() - Detach the domain from pasid of device
+ * @domain: the iommu domain.
+ * @dev: the attached device.
+ * @pasid: the pasid of the device.
+ *
+ * The @domain must have been attached to @pasid of the @dev with
+ * iommu_attach_device_pasid().
+ */
+void iommu_detach_device_pasid(struct iommu_domain *domain, struct device *dev,
+ ioasid_t pasid)
+{
+ struct iommu_group *group = iommu_group_get(dev);
+
+ mutex_lock(&group->mutex);
+ __iommu_remove_group_pasid(group, pasid);
+ WARN_ON(xa_erase(&group->pasid_array, pasid) != domain);
+ mutex_unlock(&group->mutex);
+
+ iommu_group_put(group);
+}
+EXPORT_SYMBOL_GPL(iommu_detach_device_pasid);
+
+/*
+ * iommu_get_domain_for_dev_pasid() - Retrieve domain for @pasid of @dev
+ * @dev: the queried device
+ * @pasid: the pasid of the device
+ * @type: matched domain type, 0 for any match
+ *
+ * This is a variant of iommu_get_domain_for_dev(). It returns the existing
+ * domain attached to pasid of a device. Callers must hold a lock around this
+ * function, and both iommu_attach/detach_dev_pasid() whenever a domain of
+ * type is being manipulated. This API does not internally resolve races with
+ * attach/detach.
+ *
+ * Return: attached domain on success, NULL otherwise.
+ */
+struct iommu_domain *iommu_get_domain_for_dev_pasid(struct device *dev,
+ ioasid_t pasid,
+ unsigned int type)
+{
+ struct iommu_domain *domain;
+ struct iommu_group *group;
+
+ group = iommu_group_get(dev);
+ if (!group)
+ return NULL;
+
+ xa_lock(&group->pasid_array);
+ domain = xa_load(&group->pasid_array, pasid);
+ if (type && domain && domain->type != type)
+ domain = ERR_PTR(-EBUSY);
+ xa_unlock(&group->pasid_array);
+ iommu_group_put(group);
+
+ return domain;
+}
+EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev_pasid);
+
+struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,
+ struct mm_struct *mm)
+{
+ const struct iommu_ops *ops = dev_iommu_ops(dev);
+ struct iommu_domain *domain;
+
+ domain = ops->domain_alloc(IOMMU_DOMAIN_SVA);
+ if (!domain)
+ return NULL;
+
+ domain->type = IOMMU_DOMAIN_SVA;
+ mmgrab(mm);
+ domain->mm = mm;
+ domain->iopf_handler = iommu_sva_handle_iopf;
+ domain->fault_data = mm;
+
+ return domain;
+}
+
+ioasid_t iommu_alloc_global_pasid(struct device *dev)
+{
+ int ret;
+
+ /* max_pasids == 0 means that the device does not support PASID */
+ if (!dev->iommu->max_pasids)
+ return IOMMU_PASID_INVALID;
+
+ /*
+ * max_pasids is set up by vendor driver based on number of PASID bits
+ * supported but the IDA allocation is inclusive.
+ */
+ ret = ida_alloc_range(&iommu_global_pasid_ida, IOMMU_FIRST_GLOBAL_PASID,
+ dev->iommu->max_pasids - 1, GFP_KERNEL);
+ return ret < 0 ? IOMMU_PASID_INVALID : ret;
+}
+EXPORT_SYMBOL_GPL(iommu_alloc_global_pasid);
+
+void iommu_free_global_pasid(ioasid_t pasid)
+{
+ if (WARN_ON(pasid == IOMMU_PASID_INVALID))
+ return;
+
+ ida_free(&iommu_global_pasid_ida, pasid);
+}
+EXPORT_SYMBOL_GPL(iommu_free_global_pasid);