diff options
Diffstat (limited to 'drivers/iommu/iommu.c')
| -rw-r--r-- | drivers/iommu/iommu.c | 231 |
1 files changed, 155 insertions, 76 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index f17a1113f3d6..68e648b55767 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -148,7 +148,7 @@ struct iommu_group_attribute iommu_group_attr_##_name = \ static LIST_HEAD(iommu_device_list); static DEFINE_SPINLOCK(iommu_device_lock); -static struct bus_type * const iommu_buses[] = { +static const struct bus_type * const iommu_buses[] = { &platform_bus_type, #ifdef CONFIG_PCI &pci_bus_type, @@ -257,13 +257,6 @@ int iommu_device_register(struct iommu_device *iommu, /* We need to be able to take module references appropriately */ if (WARN_ON(is_module_address((unsigned long)ops) && !ops->owner)) return -EINVAL; - /* - * Temporarily enforce global restriction to a single driver. This was - * already the de-facto behaviour, since any possible combination of - * existing drivers would compete for at least the PCI or platform bus. - */ - if (iommu_buses[0]->iommu_ops && iommu_buses[0]->iommu_ops != ops) - return -EBUSY; iommu->ops = ops; if (hwdev) @@ -273,10 +266,8 @@ int iommu_device_register(struct iommu_device *iommu, list_add_tail(&iommu->list, &iommu_device_list); spin_unlock(&iommu_device_lock); - for (int i = 0; i < ARRAY_SIZE(iommu_buses) && !err; i++) { - iommu_buses[i]->iommu_ops = ops; + for (int i = 0; i < ARRAY_SIZE(iommu_buses) && !err; i++) err = bus_iommu_probe(iommu_buses[i]); - } if (err) iommu_device_unregister(iommu); return err; @@ -329,7 +320,6 @@ int iommu_device_register_bus(struct iommu_device *iommu, list_add_tail(&iommu->list, &iommu_device_list); spin_unlock(&iommu_device_lock); - bus->iommu_ops = ops; err = bus_iommu_probe(bus); if (err) { iommu_device_unregister_bus(iommu, bus, nb); @@ -344,6 +334,8 @@ static struct dev_iommu *dev_iommu_get(struct device *dev) { struct dev_iommu *param = dev->iommu; + lockdep_assert_held(&iommu_probe_device_lock); + if (param) return param; @@ -368,6 +360,15 @@ static void dev_iommu_free(struct device *dev) kfree(param); } +/* + * 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. + */ +static bool dev_has_iommu(struct device *dev) +{ + return dev->iommu && dev->iommu->iommu_dev; +} + static u32 dev_iommu_get_max_pasids(struct device *dev) { u32 max_pasids = 0, bits = 0; @@ -386,6 +387,15 @@ static u32 dev_iommu_get_max_pasids(struct device *dev) return min_t(u32, max_pasids, dev->iommu->iommu_dev->max_pasids); } +void dev_iommu_priv_set(struct device *dev, void *priv) +{ + /* FSL_PAMU does something weird */ + if (!IS_ENABLED(CONFIG_FSL_PAMU)) + lockdep_assert_held(&iommu_probe_device_lock); + dev->iommu->priv = priv; +} +EXPORT_SYMBOL_GPL(dev_iommu_priv_set); + /* * Init the dev->iommu and dev->iommu_group in the struct device and get the * driver probed @@ -485,14 +495,30 @@ static void iommu_deinit_device(struct device *dev) 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; + const struct iommu_ops *ops; + struct iommu_fwspec *fwspec; struct iommu_group *group; - static DEFINE_MUTEX(iommu_probe_device_lock); struct group_device *gdev; int ret; + /* + * For FDT-based systems and ACPI IORT/VIOT, drivers register IOMMU + * instances with non-NULL fwnodes, and client devices should have been + * identified with a fwspec by this point. Otherwise, we can currently + * assume that only one of Intel, AMD, s390, PAMU or legacy SMMUv2 can + * be present, and that any of their registered instances has suitable + * ops for probing, and thus cheekily co-opt the same mechanism. + */ + fwspec = dev_iommu_fwspec_get(dev); + if (fwspec && fwspec->ops) + ops = fwspec->ops; + else + ops = iommu_ops_from_fwnode(NULL); + if (!ops) return -ENODEV; /* @@ -502,17 +528,15 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list * probably be able to use device_lock() here to minimise the scope, * but for now enforcing a simple global ordering is fine. */ - mutex_lock(&iommu_probe_device_lock); + lockdep_assert_held(&iommu_probe_device_lock); /* Device is probed already if in a group */ - if (dev->iommu_group) { - ret = 0; - goto out_unlock; - } + if (dev->iommu_group) + return 0; ret = iommu_init_device(dev, ops); if (ret) - goto out_unlock; + return ret; group = dev->iommu_group; gdev = iommu_group_alloc_device(group, dev); @@ -548,7 +572,6 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list list_add_tail(&group->entry, group_list); } mutex_unlock(&group->mutex); - mutex_unlock(&iommu_probe_device_lock); if (dev_is_pci(dev)) iommu_dma_set_pci_32bit_workaround(dev); @@ -562,8 +585,6 @@ err_put_group: iommu_deinit_device(dev); mutex_unlock(&group->mutex); iommu_group_put(group); -out_unlock: - mutex_unlock(&iommu_probe_device_lock); return ret; } @@ -573,7 +594,9 @@ 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; @@ -620,7 +643,7 @@ static void __iommu_group_remove_device(struct device *dev) list_del(&device->list); __iommu_group_free_device(group, device); - if (dev->iommu && dev->iommu->iommu_dev) + if (dev_has_iommu(dev)) iommu_deinit_device(dev); else dev->iommu_group = NULL; @@ -819,7 +842,7 @@ int iommu_get_group_resv_regions(struct iommu_group *group, * Non-API groups still expose reserved_regions in sysfs, * so filter out calls that get here that way. */ - if (!device->dev->iommu) + if (!dev_has_iommu(device->dev)) break; INIT_LIST_HEAD(&dev_resv_regions); @@ -1225,6 +1248,12 @@ void iommu_group_remove_device(struct device *dev) } EXPORT_SYMBOL_GPL(iommu_group_remove_device); +static struct device *iommu_group_first_dev(struct iommu_group *group) +{ + lockdep_assert_held(&group->mutex); + return list_first_entry(&group->devices, struct group_device, list)->dev; +} + /** * iommu_group_for_each_dev - iterate over each device in the group * @group: the group @@ -1753,30 +1782,13 @@ __iommu_group_alloc_default_domain(struct iommu_group *group, int req_type) } /* - * Returns the iommu_ops for the devices in an iommu group. - * - * It is assumed that all devices in an iommu group are managed by a single - * IOMMU unit. Therefore, this returns the dev_iommu_ops of the first device - * in the group. - */ -static const struct iommu_ops *group_iommu_ops(struct iommu_group *group) -{ - struct group_device *device = - list_first_entry(&group->devices, struct group_device, list); - - lockdep_assert_held(&group->mutex); - - return dev_iommu_ops(device->dev); -} - -/* * 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 iommu_ops *ops = group_iommu_ops(group); + const struct iommu_ops *ops = dev_iommu_ops(iommu_group_first_dev(group)); struct iommu_domain *dom; lockdep_assert_held(&group->mutex); @@ -1788,7 +1800,7 @@ iommu_group_alloc_default_domain(struct iommu_group *group, int req_type) */ if (ops->default_domain) { if (req_type) - return NULL; + return ERR_PTR(-EINVAL); return ops->default_domain; } @@ -1797,15 +1809,15 @@ iommu_group_alloc_default_domain(struct iommu_group *group, int 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 (dom) + if (!IS_ERR(dom)) return dom; /* Otherwise IDENTITY and DMA_FQ defaults will try DMA */ if (iommu_def_domain_type == IOMMU_DOMAIN_DMA) - return NULL; + return ERR_PTR(-EINVAL); dom = __iommu_group_alloc_default_domain(group, IOMMU_DOMAIN_DMA); - if (!dom) - return NULL; + 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); @@ -1822,7 +1834,9 @@ 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; @@ -1854,7 +1868,7 @@ static int iommu_bus_notifier(struct notifier_block *nb, static int iommu_get_def_domain_type(struct iommu_group *group, struct device *dev, int cur_type) { - const struct iommu_ops *ops = group_iommu_ops(group); + const struct iommu_ops *ops = dev_iommu_ops(dev); int type; if (!ops->def_domain_type) @@ -2003,9 +2017,28 @@ int bus_iommu_probe(const struct bus_type *bus) return 0; } +/** + * iommu_present() - make platform-specific assumptions about an IOMMU + * @bus: bus to check + * + * Do not use this function. You want device_iommu_mapped() instead. + * + * Return: true if some IOMMU is present and aware of devices on the given bus; + * in general it may not be the only IOMMU, and it may not have anything to do + * with whatever device you are ultimately interested in. + */ bool iommu_present(const struct bus_type *bus) { - return bus->iommu_ops != NULL; + bool ret = false; + + for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++) { + if (iommu_buses[i] == bus) { + spin_lock(&iommu_device_lock); + ret = !list_empty(&iommu_device_list); + spin_unlock(&iommu_device_lock); + } + } + return ret; } EXPORT_SYMBOL_GPL(iommu_present); @@ -2021,7 +2054,7 @@ bool device_iommu_capable(struct device *dev, enum iommu_cap cap) { const struct iommu_ops *ops; - if (!dev->iommu || !dev->iommu->iommu_dev) + if (!dev_has_iommu(dev)) return false; ops = dev_iommu_ops(dev); @@ -2094,12 +2127,20 @@ static struct iommu_domain *__iommu_domain_alloc(const struct iommu_ops *ops, else if (ops->domain_alloc) domain = ops->domain_alloc(alloc_type); else - return NULL; + return ERR_PTR(-EOPNOTSUPP); + /* + * Many domain_alloc ops now return ERR_PTR, make things easier for the + * driver by accepting ERR_PTR from all domain_alloc ops instead of + * having two rules. + */ + if (IS_ERR(domain)) + return domain; if (!domain) - return NULL; + return ERR_PTR(-ENOMEM); domain->type = type; + domain->owner = ops; /* * If not already set, assume all sizes by default; the driver * may override this later @@ -2110,9 +2151,14 @@ static struct iommu_domain *__iommu_domain_alloc(const struct iommu_ops *ops, if (!domain->ops) domain->ops = ops->default_domain_ops; - if (iommu_is_dma_domain(domain) && iommu_get_dma_cookie(domain)) { - iommu_domain_free(domain); - domain = NULL; + if (iommu_is_dma_domain(domain)) { + int rc; + + rc = iommu_get_dma_cookie(domain); + if (rc) { + iommu_domain_free(domain); + return ERR_PTR(rc); + } } return domain; } @@ -2120,19 +2166,40 @@ static struct iommu_domain *__iommu_domain_alloc(const struct iommu_ops *ops, static struct iommu_domain * __iommu_group_domain_alloc(struct iommu_group *group, unsigned int type) { - struct device *dev = - list_first_entry(&group->devices, struct group_device, list) - ->dev; + struct device *dev = iommu_group_first_dev(group); - return __iommu_domain_alloc(group_iommu_ops(group), dev, type); + return __iommu_domain_alloc(dev_iommu_ops(dev), dev, type); +} + +static int __iommu_domain_alloc_dev(struct device *dev, void *data) +{ + const struct iommu_ops **ops = data; + + if (!dev_has_iommu(dev)) + return 0; + + if (WARN_ONCE(*ops && *ops != dev_iommu_ops(dev), + "Multiple IOMMU drivers present for bus %s, which the public IOMMU API can't fully support yet. You will still need to disable one or more for this to work, sorry!\n", + dev_bus_name(dev))) + return -EBUSY; + + *ops = dev_iommu_ops(dev); + return 0; } struct iommu_domain *iommu_domain_alloc(const struct bus_type *bus) { - if (bus == NULL || bus->iommu_ops == NULL) + const struct iommu_ops *ops = NULL; + int err = bus_for_each_dev(bus, NULL, &ops, __iommu_domain_alloc_dev); + struct iommu_domain *domain; + + if (err || !ops) + return NULL; + + domain = __iommu_domain_alloc(ops, NULL, IOMMU_DOMAIN_UNMANAGED); + if (IS_ERR(domain)) return NULL; - return __iommu_domain_alloc(bus->iommu_ops, NULL, - IOMMU_DOMAIN_UNMANAGED); + return domain; } EXPORT_SYMBOL_GPL(iommu_domain_alloc); @@ -2267,10 +2334,16 @@ struct iommu_domain *iommu_get_dma_domain(struct device *dev) static int __iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group) { + struct device *dev; + if (group->domain && group->domain != group->default_domain && group->domain != group->blocking_domain) return -EBUSY; + dev = iommu_group_first_dev(group); + if (!dev_has_iommu(dev) || dev_iommu_ops(dev) != domain->owner) + return -EINVAL; + return __iommu_group_set_domain(group, domain); } @@ -2987,8 +3060,8 @@ EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids); */ 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 (dev_has_iommu(dev)) { + const struct iommu_ops *ops = dev_iommu_ops(dev); if (ops->dev_enable_feat) return ops->dev_enable_feat(dev, feat); @@ -3003,8 +3076,8 @@ EXPORT_SYMBOL_GPL(iommu_dev_enable_feature); */ 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 (dev_has_iommu(dev)) { + const struct iommu_ops *ops = dev_iommu_ops(dev); if (ops->dev_disable_feat) return ops->dev_disable_feat(dev, feat); @@ -3041,8 +3114,8 @@ static int iommu_setup_default_domain(struct iommu_group *group, return -EINVAL; dom = iommu_group_alloc_default_domain(group, req_type); - if (!dom) - return -ENODEV; + if (IS_ERR(dom)) + return PTR_ERR(dom); if (group->default_domain == dom) return 0; @@ -3243,21 +3316,23 @@ void iommu_device_unuse_default_domain(struct device *dev) static int __iommu_group_alloc_blocking_domain(struct iommu_group *group) { + struct iommu_domain *domain; + if (group->blocking_domain) return 0; - group->blocking_domain = - __iommu_group_domain_alloc(group, IOMMU_DOMAIN_BLOCKED); - if (!group->blocking_domain) { + domain = __iommu_group_domain_alloc(group, IOMMU_DOMAIN_BLOCKED); + if (IS_ERR(domain)) { /* * For drivers that do not yet understand IOMMU_DOMAIN_BLOCKED * create an empty domain instead. */ - group->blocking_domain = __iommu_group_domain_alloc( - group, IOMMU_DOMAIN_UNMANAGED); - if (!group->blocking_domain) - return -EINVAL; + domain = __iommu_group_domain_alloc(group, + IOMMU_DOMAIN_UNMANAGED); + if (IS_ERR(domain)) + return PTR_ERR(domain); } + group->blocking_domain = domain; return 0; } @@ -3462,6 +3537,9 @@ int iommu_attach_device_pasid(struct iommu_domain *domain, if (!group) return -ENODEV; + if (!dev_has_iommu(dev) || dev_iommu_ops(dev) != domain->owner) + return -EINVAL; + mutex_lock(&group->mutex); curr = xa_cmpxchg(&group->pasid_array, pasid, NULL, domain, GFP_KERNEL); if (curr) { @@ -3550,6 +3628,7 @@ struct iommu_domain *iommu_sva_domain_alloc(struct device *dev, domain->type = IOMMU_DOMAIN_SVA; mmgrab(mm); domain->mm = mm; + domain->owner = ops; domain->iopf_handler = iommu_sva_handle_iopf; domain->fault_data = mm; |