/* 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)
/* * Use a function instead of an array here because the domain-type is a * bit-field, so an array would waste memory.
*/ staticconstchar *iommu_domain_type_str(unsignedint 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"; case IOMMU_DOMAIN_PLATFORM: return"Platform"; default: return"Unknown";
}
}
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);
/** * 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, conststruct 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((unsignedlong)ops) && !ops->owner)) return -EINVAL;
iommu->ops = ops; if (hwdev)
iommu->fwnode = dev_fwnode(hwdev);
/* Pairs with the alloc in generic_single_device_group() */
iommu_group_put(iommu->singleton_group);
iommu->singleton_group = NULL;
}
EXPORT_SYMBOL_GPL(iommu_device_unregister);
/* * 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, conststruct iommu_ops *ops, conststruct bus_type *bus, struct notifier_block *nb)
{ int err;
/* * Internal equivalent of device_iommu_mapped() for when we care that a device * actually has API ops, and don't want false positives from VFIO-only groups.
*/ staticbool dev_has_iommu(struct device *dev)
{ return dev->iommu && dev->iommu->iommu_dev;
}
/* * Init the dev->iommu and dev->iommu_group in the struct device and get the * driver probed
*/ staticint iommu_init_device(struct device *dev)
{ conststruct iommu_ops *ops; struct iommu_device *iommu_dev; struct iommu_group *group; int ret;
if (!dev_iommu_get(dev)) return -ENOMEM; /* * For FDT-based systems and ACPI IORT/VIOT, the common firmware parsing * is buried in the bus dma_configure path. Properly unpicking that is * still a big job, so for now just invoke the whole thing. The device * already having a driver bound means dma_configure has already run and * found no IOMMU to wait for, so there's no point calling it again.
*/ if (!dev->iommu->fwspec && !dev->driver && dev->bus->dma_configure) {
mutex_unlock(&iommu_probe_device_lock);
dev->bus->dma_configure(dev);
mutex_lock(&iommu_probe_device_lock); /* If another instance finished the job for us, skip it */ if (!dev->iommu || dev->iommu_group) return -ENODEV;
} /* * At this point, relevant devices either now have a fwspec which will * match ops registered with a non-NULL fwnode, or we can reasonably * assume that only one of Intel, AMD, s390, PAMU or legacy SMMUv2 can * be present, and that any of their registered instances has suitable * ops for probing, and thus cheekily co-opt the same mechanism.
*/
ops = iommu_fwspec_ops(dev->iommu->fwspec); if (!ops) {
ret = -ENODEV; goto err_free;
}
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;
}
dev->iommu->iommu_dev = iommu_dev;
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->max_pasids = dev_iommu_get_max_pasids(dev); if (ops->is_attach_deferred)
dev->iommu->attach_deferred = ops->is_attach_deferred(dev); return 0;
/* * release_device() must stop using any attached domain on the device. * If there are still other devices in the group, they are not affected * by this callback. * * If the iommu driver provides release_domain, the core code ensures * that domain is attached prior to calling release_device. Drivers can * use this to enforce a translation on the idle iommu. Typically, the * global static blocked_domain is a good choice. * * Otherwise, the iommu driver must set the device to either an identity * or a blocking translation in release_device() and stop using any * domain pointer, as it is going to be freed. * * Regardless, if a delayed attach never occurred, then the release * should still avoid touching any hardware configuration either.
*/ if (!dev->iommu->attach_deferred && ops->release_domain)
ops->release_domain->ops->attach_dev(ops->release_domain, dev);
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); #ifdef CONFIG_IOMMU_DMA
dev->dma_iommu = false; #endif
}
/* * 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); if (ret) return ret; /* * And if we do now see any replay calls, they would indicate someone * misusing the dma_configure path outside bus code.
*/ if (dev->driver)
dev_WARN(dev, "late IOMMU probe at driver bind, something fishy here!\n");
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;
} elseif (!group->default_domain && !group_list) {
ret = iommu_setup_default_domain(group, 0); if (ret) goto err_remove_gdev;
} elseif (!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);
}
if (group->default_domain)
iommu_setup_dma_ops(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. */ staticvoid __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;
/** * 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.
*/ staticint 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;
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);
/** * 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);
/* * 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);
}
/** * 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, constchar *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;
}
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;
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;
}
}
}
out:
iommu_put_resv_regions(dev, &mappings);
return ret;
}
/* This is undone by __iommu_group_free_device() */ staticstruct 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_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);
#if IS_ENABLED(CONFIG_LOCKDEP) && IS_ENABLED(CONFIG_IOMMU_API) /** * iommu_group_mutex_assert - Check device group mutex lock * @dev: the device that has group param set * * This function is called by an iommu driver to check whether it holds * group mutex lock for the given device or not. * * Note that this function must be called after device group param is set.
*/ void iommu_group_mutex_assert(struct device *dev)
{ struct iommu_group *group = dev->iommu_group;
/** * 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);
/** * 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;
/** * 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_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);
/* * 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.
*/ staticstruct iommu_group *get_pci_function_alias_group(struct pci_dev *pdev, unsignedlong *devfns)
{ struct pci_dev *tmp = NULL; struct iommu_group *group;
if (!pdev->multifunction || pci_acs_enabled(pdev, REQ_ACS_FLAGS)) return NULL;
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.
*/ staticstruct iommu_group *get_pci_alias_group(struct pci_dev *pdev, unsignedlong *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;
/* 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;
}
}
}
/* * DMA alias iterator callback, return the last seen device. Stop and return * the IOMMU group if we find one along the way.
*/ staticint get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
{ struct group_for_pci_data *data = opaque;
/* * 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);
/* * Generic device_group call-back function. It just allocates one * iommu-group per iommu driver instance shared by every device * probed by that iommu driver.
*/ struct iommu_group *generic_single_device_group(struct device *dev)
{ struct iommu_device *iommu = dev->iommu->iommu_dev;
if (!iommu->singleton_group) { struct iommu_group *group;
group = iommu_group_alloc(); if (IS_ERR(group)) return group;
iommu->singleton_group = group;
} return iommu_group_ref_get(iommu->singleton_group);
}
EXPORT_SYMBOL_GPL(generic_single_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, (unsignedlong *)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, (unsignedlong *)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);
if (group->default_domain && group->default_domain->type == req_type) return group->default_domain;
/* * When allocating the DMA API domain assume that the driver is going to * use PASID and make sure the RID's domain is PASID compatible.
*/ if (req_type & __IOMMU_DOMAIN_PAGING) {
dom = __iommu_paging_domain_alloc_flags(dev, req_type,
dev->iommu->max_pasids ? IOMMU_HWPT_ALLOC_PASID : 0);
/* * If driver does not support PASID feature then * try to allocate non-PASID domain
*/ if (PTR_ERR(dom) == -EOPNOTSUPP)
dom = __iommu_paging_domain_alloc_flags(dev, req_type, 0);
return dom;
}
if (req_type == IOMMU_DOMAIN_IDENTITY) return __iommu_alloc_identity_domain(dev);
return ERR_PTR(-EINVAL);
}
/* * req_type of 0 means "auto" which means to select a domain based on * iommu_def_domain_type or what the driver actually supports.
*/ staticstruct iommu_domain *
iommu_group_alloc_default_domain(struct iommu_group *group, int req_type)
{ conststruct iommu_ops *ops = dev_iommu_ops(iommu_group_first_dev(group)); struct iommu_domain *dom;
lockdep_assert_held(&group->mutex);
/* * Allow legacy drivers to specify the domain that will be the default * domain. This should always be either an IDENTITY/BLOCKED/PLATFORM * domain. Do not use in new drivers.
*/ if (ops->default_domain) { if (req_type != ops->default_domain->type) return ERR_PTR(-EINVAL); return ops->default_domain;
}
if (req_type) return __iommu_group_alloc_default_domain(group, req_type);
/* The driver gave no guidance on what type to use, try the default */
dom = __iommu_group_alloc_default_domain(group, iommu_def_domain_type); if (!IS_ERR(dom)) return dom;
/* Otherwise IDENTITY and DMA_FQ defaults will try DMA */ if (iommu_def_domain_type == IOMMU_DOMAIN_DMA) return ERR_PTR(-EINVAL);
dom = __iommu_group_alloc_default_domain(group, IOMMU_DOMAIN_DMA); if (IS_ERR(dom)) return dom;
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;
}
mutex_lock(&iommu_probe_device_lock);
ret = __iommu_probe_device(dev, group_list);
mutex_unlock(&iommu_probe_device_lock); if (ret == -ENODEV)
ret = 0;
/* * Combine the driver's chosen def_domain_type across all the devices in a * group. Drivers must give a consistent result.
*/ staticint iommu_get_def_domain_type(struct iommu_group *group, struct device *dev, int cur_type)
{ conststruct iommu_ops *ops = dev_iommu_ops(dev); int type;
if (ops->default_domain) { /* * Drivers that declare a global static default_domain will * always choose that.
*/
type = ops->default_domain->type;
} else { if (ops->def_domain_type)
type = ops->def_domain_type(dev); else return cur_type;
} if (!type || cur_type == type) return cur_type; if (!cur_type) return type;
dev_err_ratelimited(
dev, "IOMMU driver error, requesting conflicting def_domain_type, %s and %s, for devices in group %u.\n",
iommu_domain_type_str(cur_type), iommu_domain_type_str(type),
group->id);
/* * Try to recover, drivers are allowed to force IDENTITY or DMA, IDENTITY * takes precedence.
*/ if (type == IOMMU_DOMAIN_IDENTITY) return type; return cur_type;
}
/* * A target_type of 0 will select the best domain type. 0 can be returned in * this case meaning the global default should be used.
*/ staticint iommu_get_default_domain_type(struct iommu_group *group, int target_type)
{ struct device *untrusted = NULL; struct group_device *gdev; int driver_type = 0;
lockdep_assert_held(&group->mutex);
/* * ARM32 drivers supporting CONFIG_ARM_DMA_USE_IOMMU can declare an * identity_domain and it will automatically become their default * domain. Later on ARM_DMA_USE_IOMMU will install its UNMANAGED domain. * Override the selection to IDENTITY.
*/ if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)) {
static_assert(!(IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) &&
IS_ENABLED(CONFIG_IOMMU_DMA)));
driver_type = IOMMU_DOMAIN_IDENTITY;
}
if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted) { /* * No ARM32 using systems will set untrusted, it cannot * work.
*/ if (WARN_ON(IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU))) return -1;
untrusted = gdev->dev;
}
}
/* * If the common dma ops are not selected in kconfig then we cannot use * IOMMU_DOMAIN_DMA at all. Force IDENTITY if nothing else has been * selected.
*/ if (!IS_ENABLED(CONFIG_IOMMU_DMA)) { if (WARN_ON(driver_type == IOMMU_DOMAIN_DMA)) return -1; if (!driver_type)
driver_type = IOMMU_DOMAIN_IDENTITY;
}
if (untrusted) { if (driver_type && driver_type != IOMMU_DOMAIN_DMA) {
dev_err_ratelimited(
untrusted, "Device is not trusted, but driver is overriding group %u to %s, refusing to probe.\n",
group->id, iommu_domain_type_str(driver_type)); return -1;
}
driver_type = IOMMU_DOMAIN_DMA;
}
if (target_type) { if (driver_type && target_type != driver_type) return -1; return target_type;
} return driver_type;
}
/* 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;
}
for_each_group_device(group, gdev)
iommu_setup_dma_ops(gdev->dev);
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;
}
/** * 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)
{ conststruct iommu_ops *ops;
if (!dev_has_iommu(dev)) returnfalse;
ops = dev_iommu_ops(dev); if (!ops->capable) returnfalse;
/** * 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;
/** * 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)
{ if (WARN_ON(!domain || domain->cookie_type != IOMMU_COOKIE_NONE)) return;
/** * iommu_paging_domain_alloc_flags() - Allocate a paging domain * @dev: device for which the domain is allocated * @flags: Bitmap of iommufd_hwpt_alloc_flags * * Allocate a paging domain which will be managed by a kernel driver. Return * allocated domain if successful, or an ERR pointer for failure.
*/ struct iommu_domain *iommu_paging_domain_alloc_flags(struct device *dev, unsignedint flags)
{ return __iommu_paging_domain_alloc_flags(dev,
IOMMU_DOMAIN_UNMANAGED, flags);
}
EXPORT_SYMBOL_GPL(iommu_paging_domain_alloc_flags);
void iommu_domain_free(struct iommu_domain *domain)
{ switch (domain->cookie_type) { case IOMMU_COOKIE_DMA_IOVA:
iommu_put_dma_cookie(domain); break; case IOMMU_COOKIE_DMA_MSI:
iommu_put_msi_cookie(domain); break; case IOMMU_COOKIE_SVA:
mmdrop(domain->mm); break; default: break;
} if (domain->ops->free)
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.
*/ staticvoid __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;
staticint __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)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group; int ret;
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;
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)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group;
struct iommu_domain *iommu_get_domain_for_dev(struct device *dev)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group;
/* * 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;
}
dev = iommu_group_first_dev(group); if (!dev_has_iommu(dev) ||
!domain_iommu_ops_compatible(dev_iommu_ops(dev), domain)) return -EINVAL;
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);
/* * 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.
*/ staticint __iommu_group_set_domain_internal(struct iommu_group *group, struct iommu_domain *new_domain, unsignedint 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;
if (WARN_ON(!new_domain)) return -EINVAL;
/* * 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) { /* * 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)); if (gdev == last_gdev) break;
} return ret;
}
/* 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;
/* * 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 (!check_add_overflow(offset, pgsize_next, &offset_end) &&
offset_end <= size)
size = offset;
/* 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);
pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx count %zu\n",
iova, &paddr, pgsize, count);
ret = ops->map_pages(domain, iova, paddr, pgsize, count, 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);
if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING))) return 0;
if (WARN_ON(!ops->unmap_pages || domain->pgsize_bitmap == 0UL)) 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;
}
/* * Keep iterating until we either unmap 'size' bytes (or more) * or we hit an area that isn't mapped.
*/ while (unmapped < size) {
size_t pgsize, count;
/** * iommu_unmap() - Remove mappings from a range of IOVA * @domain: Domain to manipulate * @iova: IO virtual address to start * @size: Length of the range starting from @iova * * iommu_unmap() will remove a translation created by iommu_map(). It cannot * subdivide a mapping created by iommu_map(), so it should be called with IOVA * ranges that match what was passed to iommu_map(). The range can aggregate * contiguous iommu_map() calls so long as no individual range is split. * * Returns: Number of bytes of IOVA unmapped. iova + res will be the point * unmapping stopped.
*/
size_t iommu_unmap(struct iommu_domain *domain, unsignedlong 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);
/** * iommu_unmap_fast() - Remove mappings from a range of IOVA without IOTLB sync * @domain: Domain to manipulate * @iova: IO virtual address to start * @size: Length of the range starting from @iova * @iotlb_gather: range information for a pending IOTLB flush * * iommu_unmap_fast() will remove a translation created by iommu_map(). * It can't subdivide a mapping created by iommu_map(), so it should be * called with IOVA ranges that match what was passed to iommu_map(). The * range can aggregate contiguous iommu_map() calls so long as no individual * range is split. * * Basically iommu_unmap_fast() is the same as iommu_unmap() but for callers * which manage the IOTLB flushing externally to perform a batched sync. * * Returns: Number of bytes of IOVA unmapped. iova + res will be the point * unmapping stopped.
*/
size_t iommu_unmap_fast(struct iommu_domain *domain, unsignedlong 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, unsignedlong iova, struct scatterlist *sg, unsignedint nents, int prot,
gfp_t gfp)
{
size_t len = 0, mapped = 0;
phys_addr_t start; unsignedint i = 0; int ret;
while (i <= nents) {
phys_addr_t s_phys = sg_phys(sg);
if (len && s_phys != start + len) {
ret = iommu_map_nosync(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);
}
ret = iommu_sync_map(domain, iova, mapped); if (ret) goto out_err;
/** * 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, unsignedlong iova, int flags)
{ int ret = -ENOSYS;
/* * if upper layers showed interest and installed a fault handler, * invoke it.
*/ if (domain->cookie_type == IOMMU_COOKIE_FAULT_HANDLER &&
domain->handler)
ret = domain->handler(domain, dev, iova, flags,
domain->handler_token);
int iommu_set_pgtable_quirks(struct iommu_domain *domain, unsignedlong 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)
{ conststruct 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;
/** * 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.
*/ staticint 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;
dom = iommu_group_alloc_default_domain(group, req_type); if (IS_ERR(dom)) return PTR_ERR(dom);
if (group->default_domain == dom) return 0;
if (iommu_is_dma_domain(dom)) {
ret = iommu_get_dma_cookie(dom); if (ret) {
iommu_domain_free(dom); return ret;
}
}
/* * 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, constchar *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;
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;
/* Make sure dma_ops is appropriatley set */
for_each_group_device(group, gdev)
iommu_setup_dma_ops(gdev->dev);
out_unlock:
mutex_unlock(&group->mutex); return ret ?: count;
}
/** * 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)
{ /* Caller is the driver core during the pre-probe path */ struct iommu_group *group = dev->iommu_group; int ret = 0;
if (!group) return 0;
mutex_lock(&group->mutex); /* We may race against bus_iommu_probe() finalising groups here */ if (!group->default_domain) {
ret = -EPROBE_DEFER; goto unlock_out;
} if (group->owner_cnt) { if (group->domain != group->default_domain || group->owner ||
!xa_empty(&group->pasid_array)) {
ret = -EBUSY; goto unlock_out;
}
}
/** * 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)
{ /* Caller is the driver core during the post-probe path */ struct iommu_group *group = dev->iommu_group;
if (!group) return;
mutex_lock(&group->mutex); if (!WARN_ON(!group->owner_cnt || !xa_empty(&group->pasid_array)))
group->owner_cnt--;
if (ops->blocked_domain) {
group->blocking_domain = ops->blocked_domain; return 0;
}
/* * For drivers that do not yet understand IOMMU_DOMAIN_BLOCKED create an * empty PAGING domain instead.
*/
domain = iommu_paging_domain_alloc(dev); if (IS_ERR(domain)) return PTR_ERR(domain);
group->blocking_domain = domain; return 0;
}
staticint __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;
/** * 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);
/** * 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)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group; int ret = 0;
if (WARN_ON(!owner)) return -EINVAL;
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); return ret;
}
EXPORT_SYMBOL_GPL(iommu_device_claim_dma_owner);
/** * 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)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group;
/** * 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)
{ unsignedint user;
mutex_lock(&group->mutex);
user = group->owner_cnt;
mutex_unlock(&group->mutex);
for_each_group_device(group, device) { if (device->dev->iommu->max_pasids > 0) {
ret = domain->ops->set_dev_pasid(domain, device->dev,
pasid, old); if (ret) goto err_revert;
}
}
return 0;
err_revert:
last_gdev = device;
for_each_group_device(group, device) { if (device == last_gdev) break; if (device->dev->iommu->max_pasids > 0) { /* * If no old domain, undo the succeeded devices/pasid. * Otherwise, rollback the succeeded devices/pasid to * the old domain. And it is a driver bug to fail * attaching with a previously good domain.
*/ if (!old ||
WARN_ON(old->ops->set_dev_pasid(old, device->dev,
pasid, domain)))
iommu_remove_dev_pasid(device->dev, pasid, domain);
}
} return ret;
}
/* * 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. * @handle: the attach handle. * * Caller should always provide a new handle to avoid race with the paths * that have lockless reference to handle if it intends to pass a valid handle. * * Return: 0 on success, or an error.
*/ int iommu_attach_device_pasid(struct iommu_domain *domain, struct device *dev, ioasid_t pasid, struct iommu_attach_handle *handle)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group; struct group_device *device; conststruct iommu_ops *ops; void *entry; int ret;
if (!group) return -ENODEV;
ops = dev_iommu_ops(dev);
if (!domain->ops->set_dev_pasid ||
!ops->blocked_domain ||
!ops->blocked_domain->ops->set_dev_pasid) return -EOPNOTSUPP;
if (!domain_iommu_ops_compatible(ops, domain) ||
pasid == IOMMU_NO_PASID) return -EINVAL;
mutex_lock(&group->mutex);
for_each_group_device(group, device) { /* * Skip PASID validation for devices without PASID support * (max_pasids = 0). These devices cannot issue transactions * with PASID, so they don't affect group's PASID usage.
*/ if ((device->dev->iommu->max_pasids > 0) &&
(pasid >= device->dev->iommu->max_pasids)) {
ret = -EINVAL; goto out_unlock;
}
}
/* * Entry present is a failure case. Use xa_insert() instead of * xa_reserve().
*/
ret = xa_insert(&group->pasid_array, pasid, XA_ZERO_ENTRY, GFP_KERNEL); if (ret) goto out_unlock;
ret = __iommu_set_group_pasid(domain, group, pasid, NULL); if (ret) {
xa_release(&group->pasid_array, pasid); goto out_unlock;
}
/* * The xa_insert() above reserved the memory, and the group->mutex is * held, this cannot fail. The new domain cannot be visible until the * operation succeeds as we cannot tolerate PRIs becoming concurrently * queued and then failing attach.
*/
WARN_ON(xa_is_err(xa_store(&group->pasid_array,
pasid, entry, GFP_KERNEL)));
/** * iommu_replace_device_pasid - Replace the domain that a specific pasid * of the device is attached to * @domain: the new iommu domain * @dev: the attached device. * @pasid: the pasid of the device. * @handle: the attach handle. * * This API allows the pasid to switch domains. The @pasid should have been * attached. Otherwise, this fails. The pasid will keep the old configuration * if replacement failed. * * Caller should always provide a new handle to avoid race with the paths * that have lockless reference to handle if it intends to pass a valid handle. * * Return 0 on success, or an error.
*/ int iommu_replace_device_pasid(struct iommu_domain *domain, struct device *dev, ioasid_t pasid, struct iommu_attach_handle *handle)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group; struct iommu_attach_handle *entry; struct iommu_domain *curr_domain; void *curr; int ret;
if (!group) return -ENODEV;
if (!domain->ops->set_dev_pasid) return -EOPNOTSUPP;
/* * No domain (with or without handle) attached, hence not * a replace case.
*/ if (!curr) {
xa_release(&group->pasid_array, pasid);
ret = -EINVAL; goto out_unlock;
}
/* * Reusing handle is problematic as there are paths that refers * the handle without lock. To avoid race, reject the callers that * attempt it.
*/ if (curr == entry) {
WARN_ON(1);
ret = -EINVAL; goto out_unlock;
}
curr_domain = pasid_array_entry_to_domain(curr);
ret = 0;
if (curr_domain != domain) {
ret = __iommu_set_group_pasid(domain, group,
pasid, curr_domain); if (ret) goto out_unlock;
}
/* * The above xa_cmpxchg() reserved the memory, and the * group->mutex is held, this cannot fail.
*/
WARN_ON(xa_is_err(xa_store(&group->pasid_array,
pasid, entry, GFP_KERNEL)));
/* * 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)
{ /* Caller must be a probed driver on dev */ struct iommu_group *group = dev->iommu_group;
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;
/** * iommu_attach_handle_get - Return the attach handle * @group: the iommu group that domain was attached to * @pasid: the pasid within the group * @type: matched domain type, 0 for any match * * Return handle or ERR_PTR(-ENOENT) on none, ERR_PTR(-EBUSY) on mismatch. * * Return the attach handle to the caller. The life cycle of an iommu attach * handle is from the time when the domain is attached to the time when the * domain is detached. Callers are required to synchronize the call of * iommu_attach_handle_get() with domain attachment and detachment. The attach * handle can only be used during its life cycle.
*/ struct iommu_attach_handle *
iommu_attach_handle_get(struct iommu_group *group, ioasid_t pasid, unsignedint type)
{ struct iommu_attach_handle *handle; void *entry;
/** * iommu_attach_group_handle - Attach an IOMMU domain to an IOMMU group * @domain: IOMMU domain to attach * @group: IOMMU group that will be attached * @handle: attach handle * * Returns 0 on success and error code on failure. * * This is a variant of iommu_attach_group(). It allows the caller to provide * an attach handle and use it when the domain is attached. This is currently * used by IOMMUFD to deliver the I/O page faults. * * Caller should always provide a new handle to avoid race with the paths * that have lockless reference to handle.
*/ int iommu_attach_group_handle(struct iommu_domain *domain, struct iommu_group *group, struct iommu_attach_handle *handle)
{ void *entry; int ret;
if (!handle) return -EINVAL;
mutex_lock(&group->mutex);
entry = iommu_make_pasid_array_entry(domain, handle);
ret = xa_insert(&group->pasid_array,
IOMMU_NO_PASID, XA_ZERO_ENTRY, GFP_KERNEL); if (ret) goto out_unlock;
ret = __iommu_attach_group(domain, group); if (ret) {
xa_release(&group->pasid_array, IOMMU_NO_PASID); goto out_unlock;
}
/* * The xa_insert() above reserved the memory, and the group->mutex is * held, this cannot fail. The new domain cannot be visible until the * operation succeeds as we cannot tolerate PRIs becoming concurrently * queued and then failing attach.
*/
WARN_ON(xa_is_err(xa_store(&group->pasid_array,
IOMMU_NO_PASID, entry, GFP_KERNEL)));
/** * iommu_detach_group_handle - Detach an IOMMU domain from an IOMMU group * @domain: IOMMU domain to attach * @group: IOMMU group that will be attached * * Detach the specified IOMMU domain from the specified IOMMU group. * It must be used in conjunction with iommu_attach_group_handle().
*/ void iommu_detach_group_handle(struct iommu_domain *domain, struct iommu_group *group)
{
mutex_lock(&group->mutex);
__iommu_group_set_core_domain(group);
xa_erase(&group->pasid_array, IOMMU_NO_PASID);
mutex_unlock(&group->mutex);
}
EXPORT_SYMBOL_NS_GPL(iommu_detach_group_handle, "IOMMUFD_INTERNAL");
/** * iommu_replace_group_handle - replace the domain that a group is attached to * @group: IOMMU group that will be attached to the new domain * @new_domain: new IOMMU domain to replace with * @handle: attach handle * * This API allows the group to switch domains without being forced to go to * the blocking domain in-between. It allows the caller to provide an attach * handle for the new domain and use it when the domain is attached. * * If the currently attached domain is a core domain (e.g. a default_domain), * it will act just like the iommu_attach_group_handle(). * * Caller should always provide a new handle to avoid race with the paths * that have lockless reference to handle.
*/ int iommu_replace_group_handle(struct iommu_group *group, struct iommu_domain *new_domain, struct iommu_attach_handle *handle)
{ void *curr, *entry; int ret;
if (!new_domain || !handle) return -EINVAL;
mutex_lock(&group->mutex);
entry = iommu_make_pasid_array_entry(new_domain, handle);
ret = xa_reserve(&group->pasid_array, IOMMU_NO_PASID, GFP_KERNEL); if (ret) goto err_unlock;
ret = __iommu_group_set_domain(group, new_domain); if (ret) goto err_release;
#if IS_ENABLED(CONFIG_IRQ_MSI_IOMMU) /** * iommu_dma_prepare_msi() - Map the MSI page in the IOMMU domain * @desc: MSI descriptor, will store the MSI page * @msi_addr: MSI target address to be mapped * * The implementation of sw_msi() should take msi_addr and map it to * an IOVA in the domain and call msi_desc_set_iommu_msi_iova() with the * mapping information. * * Return: 0 on success or negative error code if the mapping failed.
*/ int iommu_dma_prepare_msi(struct msi_desc *desc, phys_addr_t msi_addr)
{ struct device *dev = msi_desc_to_dev(desc); struct iommu_group *group = dev->iommu_group; int ret = 0;
if (!group) return 0;
mutex_lock(&group->mutex); /* An IDENTITY domain must pass through */ if (group->domain && group->domain->type != IOMMU_DOMAIN_IDENTITY) { switch (group->domain->cookie_type) { case IOMMU_COOKIE_DMA_MSI: case IOMMU_COOKIE_DMA_IOVA:
ret = iommu_dma_sw_msi(group->domain, desc, msi_addr); break; case IOMMU_COOKIE_IOMMUFD:
ret = iommufd_sw_msi(group->domain, desc, msi_addr); break; default:
ret = -EOPNOTSUPP; break;
}
}
mutex_unlock(&group->mutex); return ret;
} #endif/* CONFIG_IRQ_MSI_IOMMU */
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.47 Sekunden
(vorverarbeitet am 2026-04-28)
¤
Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
noch Qualität der bereit gestellten Informationen zugesichert.
Bemerkung:
Die farbliche Syntaxdarstellung und die Messung sind noch experimentell.
