diff options
Diffstat (limited to 'drivers/iommu/iommufd/device.c')
| -rw-r--r-- | drivers/iommu/iommufd/device.c | 1441 |
1 files changed, 1166 insertions, 275 deletions
diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index d81f93a321af..4c842368289f 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -1,11 +1,13 @@ // SPDX-License-Identifier: GPL-2.0-only /* Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES */ +#include <linux/iommu.h> #include <linux/iommufd.h> +#include <linux/pci-ats.h> #include <linux/slab.h> -#include <linux/iommu.h> -#include <linux/irqdomain.h> +#include <uapi/linux/iommufd.h> +#include "../iommu-priv.h" #include "io_pagetable.h" #include "iommufd_private.h" @@ -16,22 +18,175 @@ MODULE_PARM_DESC( "Allow IOMMUFD to bind to devices even if the platform cannot isolate " "the MSI interrupt window. Enabling this is a security weakness."); +struct iommufd_attach { + struct iommufd_hw_pagetable *hwpt; + struct xarray device_array; +}; + +static void iommufd_group_release(struct kref *kref) +{ + struct iommufd_group *igroup = + container_of(kref, struct iommufd_group, ref); + + WARN_ON(!xa_empty(&igroup->pasid_attach)); + + xa_cmpxchg(&igroup->ictx->groups, iommu_group_id(igroup->group), igroup, + NULL, GFP_KERNEL); + iommu_group_put(igroup->group); + mutex_destroy(&igroup->lock); + kfree(igroup); +} + +static void iommufd_put_group(struct iommufd_group *group) +{ + kref_put(&group->ref, iommufd_group_release); +} + +static bool iommufd_group_try_get(struct iommufd_group *igroup, + struct iommu_group *group) +{ + if (!igroup) + return false; + /* + * group ID's cannot be re-used until the group is put back which does + * not happen if we could get an igroup pointer under the xa_lock. + */ + if (WARN_ON(igroup->group != group)) + return false; + return kref_get_unless_zero(&igroup->ref); +} + /* - * A iommufd_device object represents the binding relationship between a - * consuming driver and the iommufd. These objects are created/destroyed by - * external drivers, not by userspace. + * iommufd needs to store some more data for each iommu_group, we keep a + * parallel xarray indexed by iommu_group id to hold this instead of putting it + * in the core structure. To keep things simple the iommufd_group memory is + * unique within the iommufd_ctx. This makes it easy to check there are no + * memory leaks. */ -struct iommufd_device { - struct iommufd_object obj; - struct iommufd_ctx *ictx; - struct iommufd_hw_pagetable *hwpt; - /* Head at iommufd_hw_pagetable::devices */ - struct list_head devices_item; - /* always the physical device */ - struct device *dev; +static struct iommufd_group *iommufd_get_group(struct iommufd_ctx *ictx, + struct device *dev) +{ + struct iommufd_group *new_igroup; + struct iommufd_group *cur_igroup; + struct iommufd_group *igroup; struct iommu_group *group; - bool enforce_cache_coherency; -}; + unsigned int id; + + group = iommu_group_get(dev); + if (!group) + return ERR_PTR(-ENODEV); + + id = iommu_group_id(group); + + xa_lock(&ictx->groups); + igroup = xa_load(&ictx->groups, id); + if (iommufd_group_try_get(igroup, group)) { + xa_unlock(&ictx->groups); + iommu_group_put(group); + return igroup; + } + xa_unlock(&ictx->groups); + + new_igroup = kzalloc(sizeof(*new_igroup), GFP_KERNEL); + if (!new_igroup) { + iommu_group_put(group); + return ERR_PTR(-ENOMEM); + } + + kref_init(&new_igroup->ref); + mutex_init(&new_igroup->lock); + xa_init(&new_igroup->pasid_attach); + new_igroup->sw_msi_start = PHYS_ADDR_MAX; + /* group reference moves into new_igroup */ + new_igroup->group = group; + + /* + * The ictx is not additionally refcounted here becase all objects using + * an igroup must put it before their destroy completes. + */ + new_igroup->ictx = ictx; + + /* + * We dropped the lock so igroup is invalid. NULL is a safe and likely + * value to assume for the xa_cmpxchg algorithm. + */ + cur_igroup = NULL; + xa_lock(&ictx->groups); + while (true) { + igroup = __xa_cmpxchg(&ictx->groups, id, cur_igroup, new_igroup, + GFP_KERNEL); + if (xa_is_err(igroup)) { + xa_unlock(&ictx->groups); + iommufd_put_group(new_igroup); + return ERR_PTR(xa_err(igroup)); + } + + /* new_group was successfully installed */ + if (cur_igroup == igroup) { + xa_unlock(&ictx->groups); + return new_igroup; + } + + /* Check again if the current group is any good */ + if (iommufd_group_try_get(igroup, group)) { + xa_unlock(&ictx->groups); + iommufd_put_group(new_igroup); + return igroup; + } + cur_igroup = igroup; + } +} + +static void iommufd_device_remove_vdev(struct iommufd_device *idev) +{ + struct iommufd_vdevice *vdev; + + mutex_lock(&idev->igroup->lock); + /* prevent new references from vdev */ + idev->destroying = true; + /* vdev has been completely destroyed by userspace */ + if (!idev->vdev) + goto out_unlock; + + vdev = iommufd_get_vdevice(idev->ictx, idev->vdev->obj.id); + /* + * An ongoing vdev destroy ioctl has removed the vdev from the object + * xarray, but has not finished iommufd_vdevice_destroy() yet as it + * needs the same mutex. We exit the locking then wait on wait_cnt + * reference for the vdev destruction. + */ + if (IS_ERR(vdev)) + goto out_unlock; + + /* Should never happen */ + if (WARN_ON(vdev != idev->vdev)) { + iommufd_put_object(idev->ictx, &vdev->obj); + goto out_unlock; + } + + /* + * vdev is still alive. Hold a users refcount to prevent racing with + * userspace destruction, then use iommufd_object_tombstone_user() to + * destroy it and leave a tombstone. + */ + refcount_inc(&vdev->obj.users); + iommufd_put_object(idev->ictx, &vdev->obj); + mutex_unlock(&idev->igroup->lock); + iommufd_object_tombstone_user(idev->ictx, &vdev->obj); + return; + +out_unlock: + mutex_unlock(&idev->igroup->lock); +} + +void iommufd_device_pre_destroy(struct iommufd_object *obj) +{ + struct iommufd_device *idev = + container_of(obj, struct iommufd_device, obj); + + /* Release the wait_cnt reference on this */ + iommufd_device_remove_vdev(idev); +} void iommufd_device_destroy(struct iommufd_object *obj) { @@ -39,8 +194,9 @@ void iommufd_device_destroy(struct iommufd_object *obj) container_of(obj, struct iommufd_device, obj); iommu_device_release_dma_owner(idev->dev); - iommu_group_put(idev->group); - iommufd_ctx_put(idev->ictx); + iommufd_put_group(idev->igroup); + if (!iommufd_selftest_is_mock_dev(idev->dev)) + iommufd_ctx_put(idev->ictx); } /** @@ -63,7 +219,7 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, struct device *dev, u32 *id) { struct iommufd_device *idev; - struct iommu_group *group; + struct iommufd_group *igroup; int rc; /* @@ -73,9 +229,29 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) return ERR_PTR(-EINVAL); - group = iommu_group_get(dev); - if (!group) - return ERR_PTR(-ENODEV); + igroup = iommufd_get_group(ictx, dev); + if (IS_ERR(igroup)) + return ERR_CAST(igroup); + + /* + * For historical compat with VFIO the insecure interrupt path is + * allowed if the module parameter is set. Secure/Isolated means that a + * MemWr operation from the device (eg a simple DMA) cannot trigger an + * interrupt outside this iommufd context. + */ + if (!iommufd_selftest_is_mock_dev(dev) && + !iommu_group_has_isolated_msi(igroup->group)) { + if (!allow_unsafe_interrupts) { + rc = -EPERM; + goto out_group_put; + } + + dev_warn( + dev, + "MSI interrupts are not secure, they cannot be isolated by the platform. " + "Check that platform features like interrupt remapping are enabled. " + "Use the \"allow_unsafe_interrupts\" module parameter to override\n"); + } rc = iommu_device_claim_dma_owner(dev, ictx); if (rc) @@ -87,14 +263,15 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, goto out_release_owner; } idev->ictx = ictx; - iommufd_ctx_get(ictx); + if (!iommufd_selftest_is_mock_dev(dev)) + iommufd_ctx_get(ictx); idev->dev = dev; idev->enforce_cache_coherency = device_iommu_capable(dev, IOMMU_CAP_ENFORCE_CACHE_COHERENCY); /* The calling driver is a user until iommufd_device_unbind() */ refcount_inc(&idev->obj.users); - /* group refcount moves into iommufd_device */ - idev->group = group; + /* igroup refcount moves into iommufd_device */ + idev->igroup = igroup; /* * If the caller fails after this success it must call @@ -109,10 +286,41 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, out_release_owner: iommu_device_release_dma_owner(dev); out_group_put: - iommu_group_put(group); + iommufd_put_group(igroup); return ERR_PTR(rc); } -EXPORT_SYMBOL_NS_GPL(iommufd_device_bind, IOMMUFD); +EXPORT_SYMBOL_NS_GPL(iommufd_device_bind, "IOMMUFD"); + +/** + * iommufd_ctx_has_group - True if any device within the group is bound + * to the ictx + * @ictx: iommufd file descriptor + * @group: Pointer to a physical iommu_group struct + * + * True if any device within the group has been bound to this ictx, ex. via + * iommufd_device_bind(), therefore implying ictx ownership of the group. + */ +bool iommufd_ctx_has_group(struct iommufd_ctx *ictx, struct iommu_group *group) +{ + struct iommufd_object *obj; + unsigned long index; + + if (!ictx || !group) + return false; + + xa_lock(&ictx->objects); + xa_for_each(&ictx->objects, index, obj) { + if (obj->type == IOMMUFD_OBJ_DEVICE && + container_of(obj, struct iommufd_device, obj) + ->igroup->group == group) { + xa_unlock(&ictx->objects); + return true; + } + } + xa_unlock(&ictx->objects); + return false; +} +EXPORT_SYMBOL_NS_GPL(iommufd_ctx_has_group, "IOMMUFD"); /** * iommufd_device_unbind - Undo iommufd_device_bind() @@ -125,152 +333,548 @@ EXPORT_SYMBOL_NS_GPL(iommufd_device_bind, IOMMUFD); */ void iommufd_device_unbind(struct iommufd_device *idev) { - bool was_destroyed; + iommufd_object_destroy_user(idev->ictx, &idev->obj); +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_unbind, "IOMMUFD"); - was_destroyed = iommufd_object_destroy_user(idev->ictx, &idev->obj); - WARN_ON(!was_destroyed); +struct iommufd_ctx *iommufd_device_to_ictx(struct iommufd_device *idev) +{ + return idev->ictx; } -EXPORT_SYMBOL_NS_GPL(iommufd_device_unbind, IOMMUFD); +EXPORT_SYMBOL_NS_GPL(iommufd_device_to_ictx, "IOMMUFD"); -static int iommufd_device_setup_msi(struct iommufd_device *idev, - struct iommufd_hw_pagetable *hwpt, - phys_addr_t sw_msi_start) +u32 iommufd_device_to_id(struct iommufd_device *idev) { - int rc; + return idev->obj.id; +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_to_id, "IOMMUFD"); + +static unsigned int iommufd_group_device_num(struct iommufd_group *igroup, + ioasid_t pasid) +{ + struct iommufd_attach *attach; + struct iommufd_device *idev; + unsigned int count = 0; + unsigned long index; + + lockdep_assert_held(&igroup->lock); + + attach = xa_load(&igroup->pasid_attach, pasid); + if (attach) + xa_for_each(&attach->device_array, index, idev) + count++; + return count; +} + +#ifdef CONFIG_IRQ_MSI_IOMMU +static int iommufd_group_setup_msi(struct iommufd_group *igroup, + struct iommufd_hwpt_paging *hwpt_paging) +{ + struct iommufd_ctx *ictx = igroup->ictx; + struct iommufd_sw_msi_map *cur; + + if (igroup->sw_msi_start == PHYS_ADDR_MAX) + return 0; /* - * If the IOMMU driver gives a IOMMU_RESV_SW_MSI then it is asking us to - * call iommu_get_msi_cookie() on its behalf. This is necessary to setup - * the MSI window so iommu_dma_prepare_msi() can install pages into our - * domain after request_irq(). If it is not done interrupts will not - * work on this domain. - * - * FIXME: This is conceptually broken for iommufd since we want to allow - * userspace to change the domains, eg switch from an identity IOAS to a - * DMA IOAS. There is currently no way to create a MSI window that - * matches what the IRQ layer actually expects in a newly created - * domain. + * Install all the MSI pages the device has been using into the domain */ - if (sw_msi_start != PHYS_ADDR_MAX && !hwpt->msi_cookie) { - rc = iommu_get_msi_cookie(hwpt->domain, sw_msi_start); + guard(mutex)(&ictx->sw_msi_lock); + list_for_each_entry(cur, &ictx->sw_msi_list, sw_msi_item) { + int rc; + + if (cur->sw_msi_start != igroup->sw_msi_start || + !test_bit(cur->id, igroup->required_sw_msi.bitmap)) + continue; + + rc = iommufd_sw_msi_install(ictx, hwpt_paging, cur); if (rc) return rc; + } + return 0; +} +#else +static inline int +iommufd_group_setup_msi(struct iommufd_group *igroup, + struct iommufd_hwpt_paging *hwpt_paging) +{ + return 0; +} +#endif - /* - * iommu_get_msi_cookie() can only be called once per domain, - * it returns -EBUSY on later calls. - */ - hwpt->msi_cookie = true; +static bool +iommufd_group_first_attach(struct iommufd_group *igroup, ioasid_t pasid) +{ + lockdep_assert_held(&igroup->lock); + return !xa_load(&igroup->pasid_attach, pasid); +} + +static int +iommufd_device_attach_reserved_iova(struct iommufd_device *idev, + struct iommufd_hwpt_paging *hwpt_paging) +{ + struct iommufd_group *igroup = idev->igroup; + int rc; + + lockdep_assert_held(&igroup->lock); + + rc = iopt_table_enforce_dev_resv_regions(&hwpt_paging->ioas->iopt, + idev->dev, + &igroup->sw_msi_start); + if (rc) + return rc; + + if (iommufd_group_first_attach(igroup, IOMMU_NO_PASID)) { + rc = iommufd_group_setup_msi(igroup, hwpt_paging); + if (rc) { + iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, + idev->dev); + return rc; + } + } + return 0; +} + +/* The device attach/detach/replace helpers for attach_handle */ + +static bool iommufd_device_is_attached(struct iommufd_device *idev, + ioasid_t pasid) +{ + struct iommufd_attach *attach; + + attach = xa_load(&idev->igroup->pasid_attach, pasid); + return xa_load(&attach->device_array, idev->obj.id); +} + +static int iommufd_hwpt_pasid_compat(struct iommufd_hw_pagetable *hwpt, + struct iommufd_device *idev, + ioasid_t pasid) +{ + struct iommufd_group *igroup = idev->igroup; + + lockdep_assert_held(&igroup->lock); + + if (pasid == IOMMU_NO_PASID) { + unsigned long start = IOMMU_NO_PASID; + + if (!hwpt->pasid_compat && + xa_find_after(&igroup->pasid_attach, + &start, UINT_MAX, XA_PRESENT)) + return -EINVAL; + } else { + struct iommufd_attach *attach; + + if (!hwpt->pasid_compat) + return -EINVAL; + + attach = xa_load(&igroup->pasid_attach, IOMMU_NO_PASID); + if (attach && attach->hwpt && !attach->hwpt->pasid_compat) + return -EINVAL; } + return 0; +} + +static bool iommufd_hwpt_compatible_device(struct iommufd_hw_pagetable *hwpt, + struct iommufd_device *idev) +{ + struct pci_dev *pdev; + + if (!hwpt->fault || !dev_is_pci(idev->dev)) + return true; + /* - * For historical compat with VFIO the insecure interrupt path is - * allowed if the module parameter is set. Insecure means that a MemWr - * operation from the device (eg a simple DMA) cannot trigger an - * interrupt outside this iommufd context. + * Once we turn on PCI/PRI support for VF, the response failure code + * should not be forwarded to the hardware due to PRI being a shared + * resource between PF and VFs. There is no coordination for this + * shared capability. This waits for a vPRI reset to recover. */ - if (!device_iommu_capable(idev->dev, IOMMU_CAP_INTR_REMAP) && - !irq_domain_check_msi_remap()) { - if (!allow_unsafe_interrupts) - return -EPERM; + pdev = to_pci_dev(idev->dev); + + return (!pdev->is_virtfn || !pci_pri_supported(pdev)); +} + +static int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt, + struct iommufd_device *idev, + ioasid_t pasid) +{ + struct iommufd_attach_handle *handle; + int rc; + + if (!iommufd_hwpt_compatible_device(hwpt, idev)) + return -EINVAL; + + rc = iommufd_hwpt_pasid_compat(hwpt, idev, pasid); + if (rc) + return rc; + + handle = kzalloc(sizeof(*handle), GFP_KERNEL); + if (!handle) + return -ENOMEM; + + handle->idev = idev; + if (pasid == IOMMU_NO_PASID) + rc = iommu_attach_group_handle(hwpt->domain, idev->igroup->group, + &handle->handle); + else + rc = iommu_attach_device_pasid(hwpt->domain, idev->dev, pasid, + &handle->handle); + if (rc) + goto out_free_handle; - dev_warn( - idev->dev, - "MSI interrupts are not secure, they cannot be isolated by the platform. " - "Check that platform features like interrupt remapping are enabled. " - "Use the \"allow_unsafe_interrupts\" module parameter to override\n"); - } return 0; + +out_free_handle: + kfree(handle); + return rc; } -static bool iommufd_hw_pagetable_has_group(struct iommufd_hw_pagetable *hwpt, - struct iommu_group *group) +static struct iommufd_attach_handle * +iommufd_device_get_attach_handle(struct iommufd_device *idev, ioasid_t pasid) { - struct iommufd_device *cur_dev; + struct iommu_attach_handle *handle; - list_for_each_entry(cur_dev, &hwpt->devices, devices_item) - if (cur_dev->group == group) - return true; - return false; + lockdep_assert_held(&idev->igroup->lock); + + handle = iommu_attach_handle_get(idev->igroup->group, pasid, 0); + if (IS_ERR(handle)) + return NULL; + return to_iommufd_handle(handle); } -static int iommufd_device_do_attach(struct iommufd_device *idev, - struct iommufd_hw_pagetable *hwpt) +static void iommufd_hwpt_detach_device(struct iommufd_hw_pagetable *hwpt, + struct iommufd_device *idev, + ioasid_t pasid) { - phys_addr_t sw_msi_start = PHYS_ADDR_MAX; + struct iommufd_attach_handle *handle; + + handle = iommufd_device_get_attach_handle(idev, pasid); + if (pasid == IOMMU_NO_PASID) + iommu_detach_group_handle(hwpt->domain, idev->igroup->group); + else + iommu_detach_device_pasid(hwpt->domain, idev->dev, pasid); + + iommufd_auto_response_faults(hwpt, handle); + kfree(handle); +} + +static int iommufd_hwpt_replace_device(struct iommufd_device *idev, + ioasid_t pasid, + struct iommufd_hw_pagetable *hwpt, + struct iommufd_hw_pagetable *old) +{ + struct iommufd_attach_handle *handle, *old_handle; int rc; - mutex_lock(&hwpt->devices_lock); + if (!iommufd_hwpt_compatible_device(hwpt, idev)) + return -EINVAL; - /* - * Try to upgrade the domain we have, it is an iommu driver bug to - * report IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail - * enforce_cache_coherency when there are no devices attached to the - * domain. - */ - if (idev->enforce_cache_coherency && !hwpt->enforce_cache_coherency) { - if (hwpt->domain->ops->enforce_cache_coherency) - hwpt->enforce_cache_coherency = - hwpt->domain->ops->enforce_cache_coherency( - hwpt->domain); - if (!hwpt->enforce_cache_coherency) { - WARN_ON(list_empty(&hwpt->devices)); - rc = -EINVAL; - goto out_unlock; + rc = iommufd_hwpt_pasid_compat(hwpt, idev, pasid); + if (rc) + return rc; + + old_handle = iommufd_device_get_attach_handle(idev, pasid); + + handle = kzalloc(sizeof(*handle), GFP_KERNEL); + if (!handle) + return -ENOMEM; + + handle->idev = idev; + if (pasid == IOMMU_NO_PASID) + rc = iommu_replace_group_handle(idev->igroup->group, + hwpt->domain, &handle->handle); + else + rc = iommu_replace_device_pasid(hwpt->domain, idev->dev, + pasid, &handle->handle); + if (rc) + goto out_free_handle; + + iommufd_auto_response_faults(hwpt, old_handle); + kfree(old_handle); + + return 0; + +out_free_handle: + kfree(handle); + return rc; +} + +int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt, + struct iommufd_device *idev, ioasid_t pasid) +{ + struct iommufd_hwpt_paging *hwpt_paging = find_hwpt_paging(hwpt); + bool attach_resv = hwpt_paging && pasid == IOMMU_NO_PASID; + struct iommufd_group *igroup = idev->igroup; + struct iommufd_hw_pagetable *old_hwpt; + struct iommufd_attach *attach; + int rc; + + mutex_lock(&igroup->lock); + + attach = xa_cmpxchg(&igroup->pasid_attach, pasid, NULL, + XA_ZERO_ENTRY, GFP_KERNEL); + if (xa_is_err(attach)) { + rc = xa_err(attach); + goto err_unlock; + } + + if (!attach) { + attach = kzalloc(sizeof(*attach), GFP_KERNEL); + if (!attach) { + rc = -ENOMEM; + goto err_release_pasid; } + xa_init(&attach->device_array); } - rc = iopt_table_enforce_group_resv_regions(&hwpt->ioas->iopt, idev->dev, - idev->group, &sw_msi_start); - if (rc) - goto out_unlock; + old_hwpt = attach->hwpt; - rc = iommufd_device_setup_msi(idev, hwpt, sw_msi_start); - if (rc) - goto out_iova; + rc = xa_insert(&attach->device_array, idev->obj.id, XA_ZERO_ENTRY, + GFP_KERNEL); + if (rc) { + WARN_ON(rc == -EBUSY && !old_hwpt); + goto err_free_attach; + } + + if (old_hwpt && old_hwpt != hwpt) { + rc = -EINVAL; + goto err_release_devid; + } + + if (attach_resv) { + rc = iommufd_device_attach_reserved_iova(idev, hwpt_paging); + if (rc) + goto err_release_devid; + } /* - * FIXME: Hack around missing a device-centric iommu api, only attach to - * the group once for the first device that is in the group. + * Only attach to the group once for the first device that is in the + * group. All the other devices will follow this attachment. The user + * should attach every device individually to the hwpt as the per-device + * reserved regions are only updated during individual device + * attachment. */ - if (!iommufd_hw_pagetable_has_group(hwpt, idev->group)) { - rc = iommu_attach_group(hwpt->domain, idev->group); + if (iommufd_group_first_attach(igroup, pasid)) { + rc = iommufd_hwpt_attach_device(hwpt, idev, pasid); if (rc) - goto out_iova; + goto err_unresv; + attach->hwpt = hwpt; + WARN_ON(xa_is_err(xa_store(&igroup->pasid_attach, pasid, attach, + GFP_KERNEL))); + } + refcount_inc(&hwpt->obj.users); + WARN_ON(xa_is_err(xa_store(&attach->device_array, idev->obj.id, + idev, GFP_KERNEL))); + mutex_unlock(&igroup->lock); + return 0; +err_unresv: + if (attach_resv) + iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, idev->dev); +err_release_devid: + xa_release(&attach->device_array, idev->obj.id); +err_free_attach: + if (iommufd_group_first_attach(igroup, pasid)) + kfree(attach); +err_release_pasid: + if (iommufd_group_first_attach(igroup, pasid)) + xa_release(&igroup->pasid_attach, pasid); +err_unlock: + mutex_unlock(&igroup->lock); + return rc; +} + +struct iommufd_hw_pagetable * +iommufd_hw_pagetable_detach(struct iommufd_device *idev, ioasid_t pasid) +{ + struct iommufd_group *igroup = idev->igroup; + struct iommufd_hwpt_paging *hwpt_paging; + struct iommufd_hw_pagetable *hwpt; + struct iommufd_attach *attach; + + mutex_lock(&igroup->lock); + attach = xa_load(&igroup->pasid_attach, pasid); + if (!attach) { + mutex_unlock(&igroup->lock); + return NULL; + } + + hwpt = attach->hwpt; + hwpt_paging = find_hwpt_paging(hwpt); + + xa_erase(&attach->device_array, idev->obj.id); + if (xa_empty(&attach->device_array)) { + iommufd_hwpt_detach_device(hwpt, idev, pasid); + xa_erase(&igroup->pasid_attach, pasid); + kfree(attach); + } + if (hwpt_paging && pasid == IOMMU_NO_PASID) + iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, idev->dev); + mutex_unlock(&igroup->lock); + + iommufd_hw_pagetable_put(idev->ictx, hwpt); + + /* Caller must destroy hwpt */ + return hwpt; +} + +static struct iommufd_hw_pagetable * +iommufd_device_do_attach(struct iommufd_device *idev, ioasid_t pasid, + struct iommufd_hw_pagetable *hwpt) +{ + int rc; - if (list_empty(&hwpt->devices)) { - rc = iopt_table_add_domain(&hwpt->ioas->iopt, - hwpt->domain); + rc = iommufd_hw_pagetable_attach(hwpt, idev, pasid); + if (rc) + return ERR_PTR(rc); + return NULL; +} + +static void +iommufd_group_remove_reserved_iova(struct iommufd_group *igroup, + struct iommufd_hwpt_paging *hwpt_paging) +{ + struct iommufd_attach *attach; + struct iommufd_device *cur; + unsigned long index; + + lockdep_assert_held(&igroup->lock); + + attach = xa_load(&igroup->pasid_attach, IOMMU_NO_PASID); + xa_for_each(&attach->device_array, index, cur) + iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, cur->dev); +} + +static int +iommufd_group_do_replace_reserved_iova(struct iommufd_group *igroup, + struct iommufd_hwpt_paging *hwpt_paging) +{ + struct iommufd_hwpt_paging *old_hwpt_paging; + struct iommufd_attach *attach; + struct iommufd_device *cur; + unsigned long index; + int rc; + + lockdep_assert_held(&igroup->lock); + + attach = xa_load(&igroup->pasid_attach, IOMMU_NO_PASID); + old_hwpt_paging = find_hwpt_paging(attach->hwpt); + if (!old_hwpt_paging || hwpt_paging->ioas != old_hwpt_paging->ioas) { + xa_for_each(&attach->device_array, index, cur) { + rc = iopt_table_enforce_dev_resv_regions( + &hwpt_paging->ioas->iopt, cur->dev, NULL); if (rc) - goto out_detach; + goto err_unresv; } } - idev->hwpt = hwpt; - refcount_inc(&hwpt->obj.users); - list_add(&idev->devices_item, &hwpt->devices); - mutex_unlock(&hwpt->devices_lock); + rc = iommufd_group_setup_msi(igroup, hwpt_paging); + if (rc) + goto err_unresv; return 0; -out_detach: - iommu_detach_group(hwpt->domain, idev->group); -out_iova: - iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev); -out_unlock: - mutex_unlock(&hwpt->devices_lock); +err_unresv: + iommufd_group_remove_reserved_iova(igroup, hwpt_paging); return rc; } +static struct iommufd_hw_pagetable * +iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid, + struct iommufd_hw_pagetable *hwpt) +{ + struct iommufd_hwpt_paging *hwpt_paging = find_hwpt_paging(hwpt); + bool attach_resv = hwpt_paging && pasid == IOMMU_NO_PASID; + struct iommufd_hwpt_paging *old_hwpt_paging; + struct iommufd_group *igroup = idev->igroup; + struct iommufd_hw_pagetable *old_hwpt; + struct iommufd_attach *attach; + unsigned int num_devices; + int rc; + + mutex_lock(&igroup->lock); + + attach = xa_load(&igroup->pasid_attach, pasid); + if (!attach) { + rc = -EINVAL; + goto err_unlock; + } + + old_hwpt = attach->hwpt; + + WARN_ON(!old_hwpt || xa_empty(&attach->device_array)); + + if (!iommufd_device_is_attached(idev, pasid)) { + rc = -EINVAL; + goto err_unlock; + } + + if (hwpt == old_hwpt) { + mutex_unlock(&igroup->lock); + return NULL; + } + + if (attach_resv) { + rc = iommufd_group_do_replace_reserved_iova(igroup, hwpt_paging); + if (rc) + goto err_unlock; + } + + rc = iommufd_hwpt_replace_device(idev, pasid, hwpt, old_hwpt); + if (rc) + goto err_unresv; + + old_hwpt_paging = find_hwpt_paging(old_hwpt); + if (old_hwpt_paging && pasid == IOMMU_NO_PASID && + (!hwpt_paging || hwpt_paging->ioas != old_hwpt_paging->ioas)) + iommufd_group_remove_reserved_iova(igroup, old_hwpt_paging); + + attach->hwpt = hwpt; + + num_devices = iommufd_group_device_num(igroup, pasid); + /* + * Move the refcounts held by the device_array to the new hwpt. Retain a + * refcount for this thread as the caller will free it. + */ + refcount_add(num_devices, &hwpt->obj.users); + if (num_devices > 1) + WARN_ON(refcount_sub_and_test(num_devices - 1, + &old_hwpt->obj.users)); + mutex_unlock(&igroup->lock); + + /* Caller must destroy old_hwpt */ + return old_hwpt; +err_unresv: + if (attach_resv) + iommufd_group_remove_reserved_iova(igroup, hwpt_paging); +err_unlock: + mutex_unlock(&igroup->lock); + return ERR_PTR(rc); +} + +typedef struct iommufd_hw_pagetable *(*attach_fn)( + struct iommufd_device *idev, ioasid_t pasid, + struct iommufd_hw_pagetable *hwpt); + /* * When automatically managing the domains we search for a compatible domain in * the iopt and if one is found use it, otherwise create a new domain. * Automatic domain selection will never pick a manually created domain. */ -static int iommufd_device_auto_get_domain(struct iommufd_device *idev, - struct iommufd_ioas *ioas) +static struct iommufd_hw_pagetable * +iommufd_device_auto_get_domain(struct iommufd_device *idev, ioasid_t pasid, + struct iommufd_ioas *ioas, u32 *pt_id, + attach_fn do_attach) { + /* + * iommufd_hw_pagetable_attach() is called by + * iommufd_hw_pagetable_alloc() in immediate attachment mode, same as + * iommufd_device_do_attach(). So if we are in this mode then we prefer + * to use the immediate_attach path as it supports drivers that can't + * directly allocate a domain. + */ + bool immediate_attach = do_attach == iommufd_device_do_attach; + struct iommufd_hw_pagetable *destroy_hwpt; + struct iommufd_hwpt_paging *hwpt_paging; struct iommufd_hw_pagetable *hwpt; - int rc; /* * There is no differentiation when domains are allocated, so any domain @@ -278,157 +882,301 @@ static int iommufd_device_auto_get_domain(struct iommufd_device *idev, * other. */ mutex_lock(&ioas->mutex); - list_for_each_entry(hwpt, &ioas->hwpt_list, hwpt_item) { - if (!hwpt->auto_domain) + list_for_each_entry(hwpt_paging, &ioas->hwpt_list, hwpt_item) { + if (!hwpt_paging->auto_domain) continue; - rc = iommufd_device_do_attach(idev, hwpt); - - /* - * -EINVAL means the domain is incompatible with the device. - * Other error codes should propagate to userspace as failure. - * Success means the domain is attached. - */ - if (rc == -EINVAL) + hwpt = &hwpt_paging->common; + if (!iommufd_lock_obj(&hwpt->obj)) continue; + destroy_hwpt = (*do_attach)(idev, pasid, hwpt); + if (IS_ERR(destroy_hwpt)) { + iommufd_put_object(idev->ictx, &hwpt->obj); + /* + * -EINVAL means the domain is incompatible with the + * device. Other error codes should propagate to + * userspace as failure. Success means the domain is + * attached. + */ + if (PTR_ERR(destroy_hwpt) == -EINVAL) + continue; + goto out_unlock; + } + *pt_id = hwpt->obj.id; + iommufd_put_object(idev->ictx, &hwpt->obj); goto out_unlock; } - hwpt = iommufd_hw_pagetable_alloc(idev->ictx, ioas, idev->dev); - if (IS_ERR(hwpt)) { - rc = PTR_ERR(hwpt); + hwpt_paging = iommufd_hwpt_paging_alloc(idev->ictx, ioas, idev, pasid, + 0, immediate_attach, NULL); + if (IS_ERR(hwpt_paging)) { + destroy_hwpt = ERR_CAST(hwpt_paging); goto out_unlock; } - hwpt->auto_domain = true; + hwpt = &hwpt_paging->common; + + if (!immediate_attach) { + destroy_hwpt = (*do_attach)(idev, pasid, hwpt); + if (IS_ERR(destroy_hwpt)) + goto out_abort; + } else { + destroy_hwpt = NULL; + } - rc = iommufd_device_do_attach(idev, hwpt); - if (rc) - goto out_abort; - list_add_tail(&hwpt->hwpt_item, &ioas->hwpt_list); + hwpt_paging->auto_domain = true; + *pt_id = hwpt->obj.id; - mutex_unlock(&ioas->mutex); iommufd_object_finalize(idev->ictx, &hwpt->obj); - return 0; + mutex_unlock(&ioas->mutex); + return destroy_hwpt; out_abort: iommufd_object_abort_and_destroy(idev->ictx, &hwpt->obj); out_unlock: mutex_unlock(&ioas->mutex); - return rc; + return destroy_hwpt; } -/** - * iommufd_device_attach - Connect a device from an iommu_domain - * @idev: device to attach - * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HW_PAGETABLE - * Output the IOMMUFD_OBJ_HW_PAGETABLE ID - * - * This connects the device to an iommu_domain, either automatically or manually - * selected. Once this completes the device could do DMA. - * - * The caller should return the resulting pt_id back to userspace. - * This function is undone by calling iommufd_device_detach(). - */ -int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) +static int iommufd_device_change_pt(struct iommufd_device *idev, + ioasid_t pasid, + u32 *pt_id, attach_fn do_attach) { + struct iommufd_hw_pagetable *destroy_hwpt; struct iommufd_object *pt_obj; - int rc; pt_obj = iommufd_get_object(idev->ictx, *pt_id, IOMMUFD_OBJ_ANY); if (IS_ERR(pt_obj)) return PTR_ERR(pt_obj); switch (pt_obj->type) { - case IOMMUFD_OBJ_HW_PAGETABLE: { + case IOMMUFD_OBJ_HWPT_NESTED: + case IOMMUFD_OBJ_HWPT_PAGING: { struct iommufd_hw_pagetable *hwpt = container_of(pt_obj, struct iommufd_hw_pagetable, obj); - rc = iommufd_device_do_attach(idev, hwpt); - if (rc) + destroy_hwpt = (*do_attach)(idev, pasid, hwpt); + if (IS_ERR(destroy_hwpt)) goto out_put_pt_obj; - - mutex_lock(&hwpt->ioas->mutex); - list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list); - mutex_unlock(&hwpt->ioas->mutex); break; } case IOMMUFD_OBJ_IOAS: { struct iommufd_ioas *ioas = container_of(pt_obj, struct iommufd_ioas, obj); - rc = iommufd_device_auto_get_domain(idev, ioas); - if (rc) + destroy_hwpt = iommufd_device_auto_get_domain(idev, pasid, ioas, + pt_id, do_attach); + if (IS_ERR(destroy_hwpt)) goto out_put_pt_obj; break; } default: - rc = -EINVAL; + destroy_hwpt = ERR_PTR(-EINVAL); goto out_put_pt_obj; } + iommufd_put_object(idev->ictx, pt_obj); - refcount_inc(&idev->obj.users); - *pt_id = idev->hwpt->obj.id; - rc = 0; + /* This destruction has to be after we unlock everything */ + if (destroy_hwpt) + iommufd_hw_pagetable_put(idev->ictx, destroy_hwpt); + return 0; out_put_pt_obj: - iommufd_put_object(pt_obj); - return rc; + iommufd_put_object(idev->ictx, pt_obj); + return PTR_ERR(destroy_hwpt); } -EXPORT_SYMBOL_NS_GPL(iommufd_device_attach, IOMMUFD); /** - * iommufd_device_detach - Disconnect a device to an iommu_domain + * iommufd_device_attach - Connect a device/pasid to an iommu_domain + * @idev: device to attach + * @pasid: pasid to attach + * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HWPT_PAGING + * Output the IOMMUFD_OBJ_HWPT_PAGING ID + * + * This connects the device/pasid to an iommu_domain, either automatically + * or manually selected. Once this completes the device could do DMA with + * @pasid. @pasid is IOMMU_NO_PASID if this attach is for no pasid usage. + * + * The caller should return the resulting pt_id back to userspace. + * This function is undone by calling iommufd_device_detach(). + */ +int iommufd_device_attach(struct iommufd_device *idev, ioasid_t pasid, + u32 *pt_id) +{ + int rc; + + rc = iommufd_device_change_pt(idev, pasid, pt_id, + &iommufd_device_do_attach); + if (rc) + return rc; + + /* + * Pairs with iommufd_device_detach() - catches caller bugs attempting + * to destroy a device with an attachment. + */ + refcount_inc(&idev->obj.users); + return 0; +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_attach, "IOMMUFD"); + +/** + * iommufd_device_replace - Change the device/pasid's iommu_domain + * @idev: device to change + * @pasid: pasid to change + * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HWPT_PAGING + * Output the IOMMUFD_OBJ_HWPT_PAGING ID + * + * This is the same as:: + * + * iommufd_device_detach(); + * iommufd_device_attach(); + * + * If it fails then no change is made to the attachment. The iommu driver may + * implement this so there is no disruption in translation. This can only be + * called if iommufd_device_attach() has already succeeded. @pasid is + * IOMMU_NO_PASID for no pasid usage. + */ +int iommufd_device_replace(struct iommufd_device *idev, ioasid_t pasid, + u32 *pt_id) +{ + return iommufd_device_change_pt(idev, pasid, pt_id, + &iommufd_device_do_replace); +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_replace, "IOMMUFD"); + +/** + * iommufd_device_detach - Disconnect a device/device to an iommu_domain * @idev: device to detach + * @pasid: pasid to detach * * Undo iommufd_device_attach(). This disconnects the idev from the previously * attached pt_id. The device returns back to a blocked DMA translation. + * @pasid is IOMMU_NO_PASID for no pasid usage. + */ +void iommufd_device_detach(struct iommufd_device *idev, ioasid_t pasid) +{ + struct iommufd_hw_pagetable *hwpt; + + hwpt = iommufd_hw_pagetable_detach(idev, pasid); + if (!hwpt) + return; + refcount_dec(&idev->obj.users); +} +EXPORT_SYMBOL_NS_GPL(iommufd_device_detach, "IOMMUFD"); + +/* + * On success, it will refcount_inc() at a valid new_ioas and refcount_dec() at + * a valid cur_ioas (access->ioas). A caller passing in a valid new_ioas should + * call iommufd_put_object() if it does an iommufd_get_object() for a new_ioas. */ -void iommufd_device_detach(struct iommufd_device *idev) -{ - struct iommufd_hw_pagetable *hwpt = idev->hwpt; - - mutex_lock(&hwpt->ioas->mutex); - mutex_lock(&hwpt->devices_lock); - list_del(&idev->devices_item); - if (!iommufd_hw_pagetable_has_group(hwpt, idev->group)) { - if (list_empty(&hwpt->devices)) { - iopt_table_remove_domain(&hwpt->ioas->iopt, - hwpt->domain); - list_del(&hwpt->hwpt_item); +static int iommufd_access_change_ioas(struct iommufd_access *access, + struct iommufd_ioas *new_ioas) +{ + u32 iopt_access_list_id = access->iopt_access_list_id; + struct iommufd_ioas *cur_ioas = access->ioas; + int rc; + + lockdep_assert_held(&access->ioas_lock); + + /* We are racing with a concurrent detach, bail */ + if (cur_ioas != access->ioas_unpin) + return -EBUSY; + + if (cur_ioas == new_ioas) + return 0; + + /* + * Set ioas to NULL to block any further iommufd_access_pin_pages(). + * iommufd_access_unpin_pages() can continue using access->ioas_unpin. + */ + access->ioas = NULL; + + if (new_ioas) { + rc = iopt_add_access(&new_ioas->iopt, access); + if (rc) { + access->ioas = cur_ioas; + return rc; } - iommu_detach_group(hwpt->domain, idev->group); + refcount_inc(&new_ioas->obj.users); } - iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev); - mutex_unlock(&hwpt->devices_lock); - mutex_unlock(&hwpt->ioas->mutex); - if (hwpt->auto_domain) - iommufd_object_destroy_user(idev->ictx, &hwpt->obj); - else - refcount_dec(&hwpt->obj.users); + if (cur_ioas) { + if (!iommufd_access_is_internal(access) && access->ops->unmap) { + mutex_unlock(&access->ioas_lock); + access->ops->unmap(access->data, 0, ULONG_MAX); + mutex_lock(&access->ioas_lock); + } + iopt_remove_access(&cur_ioas->iopt, access, iopt_access_list_id); + refcount_dec(&cur_ioas->obj.users); + } - idev->hwpt = NULL; + access->ioas = new_ioas; + access->ioas_unpin = new_ioas; - refcount_dec(&idev->obj.users); + return 0; +} + +static int iommufd_access_change_ioas_id(struct iommufd_access *access, u32 id) +{ + struct iommufd_ioas *ioas = iommufd_get_ioas(access->ictx, id); + int rc; + + if (IS_ERR(ioas)) + return PTR_ERR(ioas); + rc = iommufd_access_change_ioas(access, ioas); + iommufd_put_object(access->ictx, &ioas->obj); + return rc; } -EXPORT_SYMBOL_NS_GPL(iommufd_device_detach, IOMMUFD); void iommufd_access_destroy_object(struct iommufd_object *obj) { struct iommufd_access *access = container_of(obj, struct iommufd_access, obj); - iopt_remove_access(&access->ioas->iopt, access); - iommufd_ctx_put(access->ictx); - refcount_dec(&access->ioas->obj.users); + mutex_lock(&access->ioas_lock); + if (access->ioas) + WARN_ON(iommufd_access_change_ioas(access, NULL)); + mutex_unlock(&access->ioas_lock); + if (!iommufd_access_is_internal(access)) + iommufd_ctx_put(access->ictx); +} + +static struct iommufd_access *__iommufd_access_create(struct iommufd_ctx *ictx) +{ + struct iommufd_access *access; + + /* + * There is no uAPI for the access object, but to keep things symmetric + * use the object infrastructure anyhow. + */ + access = iommufd_object_alloc(ictx, access, IOMMUFD_OBJ_ACCESS); + if (IS_ERR(access)) + return access; + + /* The calling driver is a user until iommufd_access_destroy() */ + refcount_inc(&access->obj.users); + mutex_init(&access->ioas_lock); + return access; +} + +struct iommufd_access *iommufd_access_create_internal(struct iommufd_ctx *ictx) +{ + struct iommufd_access *access; + + access = __iommufd_access_create(ictx); + if (IS_ERR(access)) + return access; + access->iova_alignment = PAGE_SIZE; + + iommufd_object_finalize(ictx, &access->obj); + return access; } /** * iommufd_access_create - Create an iommufd_access * @ictx: iommufd file descriptor - * @ioas_id: ID for a IOMMUFD_OBJ_IOAS * @ops: Driver's ops to associate with the access * @data: Opaque data to pass into ops functions + * @id: Output ID number to return to userspace for this access * * An iommufd_access allows a driver to read/write to the IOAS without using * DMA. The underlying CPU memory can be accessed using the @@ -437,53 +1185,30 @@ void iommufd_access_destroy_object(struct iommufd_object *obj) * The provided ops are required to use iommufd_access_pin_pages(). */ struct iommufd_access * -iommufd_access_create(struct iommufd_ctx *ictx, u32 ioas_id, - const struct iommufd_access_ops *ops, void *data) +iommufd_access_create(struct iommufd_ctx *ictx, + const struct iommufd_access_ops *ops, void *data, u32 *id) { struct iommufd_access *access; - struct iommufd_object *obj; - int rc; - /* - * There is no uAPI for the access object, but to keep things symmetric - * use the object infrastructure anyhow. - */ - access = iommufd_object_alloc(ictx, access, IOMMUFD_OBJ_ACCESS); + access = __iommufd_access_create(ictx); if (IS_ERR(access)) return access; access->data = data; access->ops = ops; - obj = iommufd_get_object(ictx, ioas_id, IOMMUFD_OBJ_IOAS); - if (IS_ERR(obj)) { - rc = PTR_ERR(obj); - goto out_abort; - } - access->ioas = container_of(obj, struct iommufd_ioas, obj); - iommufd_ref_to_users(obj); - if (ops->needs_pin_pages) access->iova_alignment = PAGE_SIZE; else access->iova_alignment = 1; - rc = iopt_add_access(&access->ioas->iopt, access); - if (rc) - goto out_put_ioas; - /* The calling driver is a user until iommufd_access_destroy() */ - refcount_inc(&access->obj.users); access->ictx = ictx; iommufd_ctx_get(ictx); iommufd_object_finalize(ictx, &access->obj); + *id = access->obj.id; return access; -out_put_ioas: - refcount_dec(&access->ioas->obj.users); -out_abort: - iommufd_object_abort(ictx, &access->obj); - return ERR_PTR(rc); } -EXPORT_SYMBOL_NS_GPL(iommufd_access_create, IOMMUFD); +EXPORT_SYMBOL_NS_GPL(iommufd_access_create, "IOMMUFD"); /** * iommufd_access_destroy - Destroy an iommufd_access @@ -493,12 +1218,68 @@ EXPORT_SYMBOL_NS_GPL(iommufd_access_create, IOMMUFD); */ void iommufd_access_destroy(struct iommufd_access *access) { - bool was_destroyed; + iommufd_object_destroy_user(access->ictx, &access->obj); +} +EXPORT_SYMBOL_NS_GPL(iommufd_access_destroy, "IOMMUFD"); - was_destroyed = iommufd_object_destroy_user(access->ictx, &access->obj); - WARN_ON(!was_destroyed); +void iommufd_access_detach(struct iommufd_access *access) +{ + mutex_lock(&access->ioas_lock); + if (WARN_ON(!access->ioas)) { + mutex_unlock(&access->ioas_lock); + return; + } + WARN_ON(iommufd_access_change_ioas(access, NULL)); + mutex_unlock(&access->ioas_lock); } -EXPORT_SYMBOL_NS_GPL(iommufd_access_destroy, IOMMUFD); +EXPORT_SYMBOL_NS_GPL(iommufd_access_detach, "IOMMUFD"); + +int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id) +{ + int rc; + + mutex_lock(&access->ioas_lock); + if (WARN_ON(access->ioas)) { + mutex_unlock(&access->ioas_lock); + return -EINVAL; + } + + rc = iommufd_access_change_ioas_id(access, ioas_id); + mutex_unlock(&access->ioas_lock); + return rc; +} +EXPORT_SYMBOL_NS_GPL(iommufd_access_attach, "IOMMUFD"); + +int iommufd_access_attach_internal(struct iommufd_access *access, + struct iommufd_ioas *ioas) +{ + int rc; + + mutex_lock(&access->ioas_lock); + if (WARN_ON(access->ioas)) { + mutex_unlock(&access->ioas_lock); + return -EINVAL; + } + + rc = iommufd_access_change_ioas(access, ioas); + mutex_unlock(&access->ioas_lock); + return rc; +} + +int iommufd_access_replace(struct iommufd_access *access, u32 ioas_id) +{ + int rc; + + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + rc = iommufd_access_change_ioas_id(access, ioas_id); + mutex_unlock(&access->ioas_lock); + return rc; +} +EXPORT_SYMBOL_NS_GPL(iommufd_access_replace, "IOMMUFD"); /** * iommufd_access_notify_unmap - Notify users of an iopt to stop using it @@ -526,13 +1307,14 @@ void iommufd_access_notify_unmap(struct io_pagetable *iopt, unsigned long iova, xa_lock(&ioas->iopt.access_list); xa_for_each(&ioas->iopt.access_list, index, access) { - if (!iommufd_lock_obj(&access->obj)) + if (!iommufd_lock_obj(&access->obj) || + iommufd_access_is_internal(access)) continue; xa_unlock(&ioas->iopt.access_list); access->ops->unmap(access->data, iova, length); - iommufd_put_object(&access->obj); + iommufd_put_object(access->ictx, &access->obj); xa_lock(&ioas->iopt.access_list); } xa_unlock(&ioas->iopt.access_list); @@ -550,8 +1332,9 @@ void iommufd_access_notify_unmap(struct io_pagetable *iopt, unsigned long iova, void iommufd_access_unpin_pages(struct iommufd_access *access, unsigned long iova, unsigned long length) { - struct io_pagetable *iopt = &access->ioas->iopt; + bool internal = iommufd_access_is_internal(access); struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; unsigned long last_iova; struct iopt_area *area; @@ -559,17 +1342,30 @@ void iommufd_access_unpin_pages(struct iommufd_access *access, WARN_ON(check_add_overflow(iova, length - 1, &last_iova))) return; + mutex_lock(&access->ioas_lock); + /* + * The driver must be doing something wrong if it calls this before an + * iommufd_access_attach() or after an iommufd_access_detach(). + */ + if (WARN_ON(!access->ioas_unpin)) { + mutex_unlock(&access->ioas_lock); + return; + } + iopt = &access->ioas_unpin->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) iopt_area_remove_access( area, iopt_area_iova_to_index(area, iter.cur_iova), iopt_area_iova_to_index( area, - min(last_iova, iopt_area_last_iova(area)))); - up_read(&iopt->iova_rwsem); + min(last_iova, iopt_area_last_iova(area))), + internal); WARN_ON(!iopt_area_contig_done(&iter)); + up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); } -EXPORT_SYMBOL_NS_GPL(iommufd_access_unpin_pages, IOMMUFD); +EXPORT_SYMBOL_NS_GPL(iommufd_access_unpin_pages, "IOMMUFD"); static bool iopt_area_contig_is_aligned(struct iopt_area_contig_iter *iter) { @@ -613,15 +1409,17 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, unsigned long length, struct page **out_pages, unsigned int flags) { - struct io_pagetable *iopt = &access->ioas->iopt; + bool internal = iommufd_access_is_internal(access); struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; unsigned long last_iova; struct iopt_area *area; int rc; /* Driver's ops don't support pin_pages */ if (IS_ENABLED(CONFIG_IOMMUFD_TEST) && - WARN_ON(access->iova_alignment != PAGE_SIZE || !access->ops->unmap)) + WARN_ON(access->iova_alignment != PAGE_SIZE || + (!internal && !access->ops->unmap))) return -EINVAL; if (!length) @@ -629,6 +1427,13 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, if (check_add_overflow(iova, length - 1, &last_iova)) return -EOVERFLOW; + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + iopt = &access->ioas->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) { unsigned long last = min(last_iova, iopt_area_last_iova(area)); @@ -648,7 +1453,7 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, } rc = iopt_area_add_access(area, index, last_index, out_pages, - flags); + flags, internal); if (rc) goto err_remove; out_pages += last_index - index + 1; @@ -659,6 +1464,7 @@ int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, } up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return 0; err_remove: @@ -670,12 +1476,14 @@ err_remove: iopt_area_iova_to_index(area, iter.cur_iova), iopt_area_iova_to_index( area, min(last_iova, - iopt_area_last_iova(area)))); + iopt_area_last_iova(area))), + internal); } up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return rc; } -EXPORT_SYMBOL_NS_GPL(iommufd_access_pin_pages, IOMMUFD); +EXPORT_SYMBOL_NS_GPL(iommufd_access_pin_pages, "IOMMUFD"); /** * iommufd_access_rw - Read or write data under the iova @@ -692,17 +1500,24 @@ EXPORT_SYMBOL_NS_GPL(iommufd_access_pin_pages, IOMMUFD); int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, void *data, size_t length, unsigned int flags) { - struct io_pagetable *iopt = &access->ioas->iopt; struct iopt_area_contig_iter iter; + struct io_pagetable *iopt; struct iopt_area *area; unsigned long last_iova; - int rc; + int rc = -EINVAL; if (!length) return -EINVAL; if (check_add_overflow(iova, length - 1, &last_iova)) return -EOVERFLOW; + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + iopt = &access->ioas->iopt; + down_read(&iopt->iova_rwsem); iopt_for_each_contig_area(&iter, area, iopt, iova, last_iova) { unsigned long last = min(last_iova, iopt_area_last_iova(area)); @@ -729,44 +1544,120 @@ int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, rc = -ENOENT; err_out: up_read(&iopt->iova_rwsem); + mutex_unlock(&access->ioas_lock); return rc; } -EXPORT_SYMBOL_NS_GPL(iommufd_access_rw, IOMMUFD); +EXPORT_SYMBOL_NS_GPL(iommufd_access_rw, "IOMMUFD"); -#ifdef CONFIG_IOMMUFD_TEST -/* - * Creating a real iommufd_device is too hard, bypass creating a iommufd_device - * and go directly to attaching a domain. - */ -struct iommufd_hw_pagetable * -iommufd_device_selftest_attach(struct iommufd_ctx *ictx, - struct iommufd_ioas *ioas, - struct device *mock_dev) +int iommufd_get_hw_info(struct iommufd_ucmd *ucmd) { - struct iommufd_hw_pagetable *hwpt; + const u32 SUPPORTED_FLAGS = IOMMU_HW_INFO_FLAG_INPUT_TYPE; + struct iommu_hw_info *cmd = ucmd->cmd; + void __user *user_ptr = u64_to_user_ptr(cmd->data_uptr); + const struct iommu_ops *ops; + struct iommufd_device *idev; + unsigned int data_len; + unsigned int copy_len; + void *data; int rc; - hwpt = iommufd_hw_pagetable_alloc(ictx, ioas, mock_dev); - if (IS_ERR(hwpt)) - return hwpt; + if (cmd->flags & ~SUPPORTED_FLAGS) + return -EOPNOTSUPP; + if (cmd->__reserved[0] || cmd->__reserved[1] || cmd->__reserved[2]) + return -EOPNOTSUPP; + + /* Clear the type field since drivers don't support a random input */ + if (!(cmd->flags & IOMMU_HW_INFO_FLAG_INPUT_TYPE)) + cmd->in_data_type = IOMMU_HW_INFO_TYPE_DEFAULT; + + idev = iommufd_get_device(ucmd, cmd->dev_id); + if (IS_ERR(idev)) + return PTR_ERR(idev); + + ops = dev_iommu_ops(idev->dev); + if (ops->hw_info) { + data = ops->hw_info(idev->dev, &data_len, &cmd->out_data_type); + if (IS_ERR(data)) { + rc = PTR_ERR(data); + goto out_put; + } - rc = iopt_table_add_domain(&hwpt->ioas->iopt, hwpt->domain); - if (rc) - goto out_hwpt; + /* + * drivers that have hw_info callback should have a unique + * iommu_hw_info_type. + */ + if (WARN_ON_ONCE(cmd->out_data_type == + IOMMU_HW_INFO_TYPE_NONE)) { + rc = -EOPNOTSUPP; + goto out_free; + } + } else { + cmd->out_data_type = IOMMU_HW_INFO_TYPE_NONE; + data_len = 0; + data = NULL; + } - refcount_inc(&hwpt->obj.users); - iommufd_object_finalize(ictx, &hwpt->obj); - return hwpt; + copy_len = min(cmd->data_len, data_len); + if (copy_to_user(user_ptr, data, copy_len)) { + rc = -EFAULT; + goto out_free; + } -out_hwpt: - iommufd_object_abort_and_destroy(ictx, &hwpt->obj); - return ERR_PTR(rc); -} + /* + * Zero the trailing bytes if the user buffer is bigger than the + * data size kernel actually has. + */ + if (copy_len < cmd->data_len) { + if (clear_user(user_ptr + copy_len, cmd->data_len - copy_len)) { + rc = -EFAULT; + goto out_free; + } + } -void iommufd_device_selftest_detach(struct iommufd_ctx *ictx, - struct iommufd_hw_pagetable *hwpt) -{ - iopt_table_remove_domain(&hwpt->ioas->iopt, hwpt->domain); - refcount_dec(&hwpt->obj.users); + /* + * We return the length the kernel supports so userspace may know what + * the kernel capability is. It could be larger than the input buffer. + */ + cmd->data_len = data_len; + + cmd->out_capabilities = 0; + if (device_iommu_capable(idev->dev, IOMMU_CAP_DIRTY_TRACKING)) + cmd->out_capabilities |= IOMMU_HW_CAP_DIRTY_TRACKING; + + cmd->out_max_pasid_log2 = 0; + /* + * Currently, all iommu drivers enable PASID in the probe_device() + * op if iommu and device supports it. So the max_pasids stored in + * dev->iommu indicates both PASID support and enable status. A + * non-zero dev->iommu->max_pasids means PASID is supported and + * enabled. The iommufd only reports PASID capability to userspace + * if it's enabled. + */ + if (idev->dev->iommu->max_pasids) { + cmd->out_max_pasid_log2 = ilog2(idev->dev->iommu->max_pasids); + + if (dev_is_pci(idev->dev)) { + struct pci_dev *pdev = to_pci_dev(idev->dev); + int ctrl; + + ctrl = pci_pasid_status(pdev); + + WARN_ON_ONCE(ctrl < 0 || + !(ctrl & PCI_PASID_CTRL_ENABLE)); + + if (ctrl & PCI_PASID_CTRL_EXEC) + cmd->out_capabilities |= + IOMMU_HW_CAP_PCI_PASID_EXEC; + if (ctrl & PCI_PASID_CTRL_PRIV) + cmd->out_capabilities |= + IOMMU_HW_CAP_PCI_PASID_PRIV; + } + } + + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); +out_free: + kfree(data); +out_put: + iommufd_put_object(ucmd->ictx, &idev->obj); + return rc; } -#endif |