Allow a vIOMMU object to allocate vIRQ Event Queues, with a condition that each vIOMMU can only have one single vIRQ event queue per type.
Add iommufd_eventq_virq_alloc with an iommufd_eventq_virq_ops for this new ioctl.
Signed-off-by: Nicolin Chen nicolinc@nvidia.com --- drivers/iommu/iommufd/iommufd_private.h | 59 ++++++++++ include/linux/iommufd.h | 3 + include/uapi/linux/iommufd.h | 31 ++++++ drivers/iommu/iommufd/eventq.c | 138 ++++++++++++++++++++++++ drivers/iommu/iommufd/main.c | 6 ++ drivers/iommu/iommufd/viommu.c | 2 + 6 files changed, 239 insertions(+)
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index 1c9a101cc435..fd0b87707967 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -548,6 +548,51 @@ static inline int iommufd_hwpt_replace_device(struct iommufd_device *idev, return iommu_group_replace_domain(idev->igroup->group, hwpt->domain); }
+/* + * An iommufd_eventq_virq object represents a queue to deliver vIOMMU interrupts + * to the user space. These objects are created/destroyed by the user space and + * associated with vIOMMU object(s) during the allocations. + */ +struct iommufd_eventq_virq { + struct iommufd_eventq common; + struct iommufd_viommu *viommu; + struct workqueue_struct *irq_wq; + struct list_head node; + + unsigned int type; +}; + +static inline struct iommufd_eventq_virq * +to_eventq_virq(struct iommufd_eventq *eventq) +{ + return container_of(eventq, struct iommufd_eventq_virq, common); +} + +static inline struct iommufd_eventq_virq * +iommufd_get_eventq_virq(struct iommufd_ucmd *ucmd, u32 id) +{ + return container_of(iommufd_get_object(ucmd->ictx, id, + IOMMUFD_OBJ_EVENTQ_VIRQ), + struct iommufd_eventq_virq, common.obj); +} + +int iommufd_eventq_virq_alloc(struct iommufd_ucmd *ucmd); +void iommufd_eventq_virq_destroy(struct iommufd_object *obj); +void iommufd_eventq_virq_abort(struct iommufd_object *obj); + +/* An iommufd_virq represents a vIOMMU interrupt in an eventq_virq queue */ +struct iommufd_virq { + struct iommufd_eventq_virq *eventq_virq; + struct list_head node; + ssize_t irq_len; + void *irq_data; +}; + +static inline int iommufd_eventq_virq_handler(struct iommufd_virq *virq) +{ + return iommufd_eventq_notify(&virq->eventq_virq->common, &virq->node); +} + static inline struct iommufd_viommu * iommufd_get_viommu(struct iommufd_ucmd *ucmd, u32 id) { @@ -556,6 +601,20 @@ iommufd_get_viommu(struct iommufd_ucmd *ucmd, u32 id) struct iommufd_viommu, obj); }
+static inline struct iommufd_eventq_virq * +iommufd_viommu_find_eventq_virq(struct iommufd_viommu *viommu, u32 type) +{ + struct iommufd_eventq_virq *eventq_virq, *next; + + lockdep_assert_held(&viommu->virqs_rwsem); + + list_for_each_entry_safe(eventq_virq, next, &viommu->virqs, node) { + if (eventq_virq->type == type) + return eventq_virq; + } + return NULL; +} + int iommufd_viommu_alloc_ioctl(struct iommufd_ucmd *ucmd); void iommufd_viommu_destroy(struct iommufd_object *obj); int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd); diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index 7ad105ab8090..40cc9bbb1d24 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -32,6 +32,7 @@ enum iommufd_object_type { IOMMUFD_OBJ_IOAS, IOMMUFD_OBJ_ACCESS, IOMMUFD_OBJ_EVENTQ_IOPF, + IOMMUFD_OBJ_EVENTQ_VIRQ, IOMMUFD_OBJ_VIOMMU, IOMMUFD_OBJ_VDEVICE, #ifdef CONFIG_IOMMUFD_TEST @@ -93,6 +94,8 @@ struct iommufd_viommu { const struct iommufd_viommu_ops *ops;
struct xarray vdevs; + struct list_head virqs; + struct rw_semaphore virqs_rwsem;
unsigned int type; }; diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 34810f6ae2b5..d9319f5b7c69 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -55,6 +55,7 @@ enum { IOMMUFD_CMD_VIOMMU_ALLOC = 0x90, IOMMUFD_CMD_VDEVICE_ALLOC = 0x91, IOMMUFD_CMD_IOAS_CHANGE_PROCESS = 0x92, + IOMMUFD_CMD_VIRQ_ALLOC = 0x93, };
/** @@ -1012,4 +1013,34 @@ struct iommu_ioas_change_process { #define IOMMU_IOAS_CHANGE_PROCESS \ _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_CHANGE_PROCESS)
+/** + * enum iommu_virq_type - Virtual IRQ Type + * @IOMMU_VIRQ_TYPE_NONE: INVALID type + */ +enum iommu_virq_type { + IOMMU_VIRQ_TYPE_NONE = 0, +}; + +/** + * struct iommu_virq_alloc - ioctl(IOMMU_VIRQ_ALLOC) + * @size: sizeof(struct iommu_virq_alloc) + * @flags: Must be 0 + * @viommu: virtual IOMMU ID to associate the virtual IRQ with + * @type: Type of the virtual IRQ. Must be defined in enum iommu_virq_type + * @out_virq_id: The ID of the new virtual IRQ + * @out_fault_fd: The fd of the new virtual IRQ. User space must close the + * successfully returned fd after using it + * + * Explicitly allocate a virtual IRQ handler for a vIOMMU. A vIOMMU can have + * multiple FDs for different @type, but is confined to one FD per @type. + */ +struct iommu_virq_alloc { + __u32 size; + __u32 flags; + __u32 viommu_id; + __u32 type; + __u32 out_virq_id; + __u32 out_virq_fd; +}; +#define IOMMU_VIRQ_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VIRQ_ALLOC) #endif diff --git a/drivers/iommu/iommufd/eventq.c b/drivers/iommu/iommufd/eventq.c index 3674961a45c2..cf07b3c21f1e 100644 --- a/drivers/iommu/iommufd/eventq.c +++ b/drivers/iommu/iommufd/eventq.c @@ -346,6 +346,75 @@ static const struct iommufd_eventq_ops iommufd_eventq_iopf_ops = { .write = &iommufd_eventq_iopf_fops_write, };
+/* IOMMUFD_OBJ_EVENTQ_VIRQ Functions */ + +void iommufd_eventq_virq_abort(struct iommufd_object *obj) +{ + struct iommufd_eventq *eventq = + container_of(obj, struct iommufd_eventq, obj); + struct iommufd_eventq_virq *eventq_virq = to_eventq_virq(eventq); + struct iommufd_viommu *viommu = eventq_virq->viommu; + struct iommufd_virq *virq, *next; + + lockdep_assert_held_write(&viommu->virqs_rwsem); + + list_for_each_entry_safe(virq, next, &eventq->deliver, node) { + list_del(&virq->node); + kfree(virq); + } + + if (eventq_virq->irq_wq) + destroy_workqueue(eventq_virq->irq_wq); + refcount_dec(&viommu->obj.users); + mutex_destroy(&eventq->mutex); + list_del(&eventq_virq->node); +} + +void iommufd_eventq_virq_destroy(struct iommufd_object *obj) +{ + struct iommufd_eventq_virq *eventq_virq = + to_eventq_virq(container_of(obj, struct iommufd_eventq, obj)); + + down_write(&eventq_virq->viommu->virqs_rwsem); + iommufd_eventq_virq_abort(obj); + up_write(&eventq_virq->viommu->virqs_rwsem); +} + +static ssize_t iommufd_eventq_virq_fops_read(struct iommufd_eventq *eventq, + char __user *buf, size_t count, + loff_t *ppos) +{ + size_t done = 0; + int rc = 0; + + if (*ppos) + return -ESPIPE; + + mutex_lock(&eventq->mutex); + while (!list_empty(&eventq->deliver) && count > done) { + struct iommufd_virq *virq = list_first_entry( + &eventq->deliver, struct iommufd_virq, node); + + if (virq->irq_len > count - done) + break; + + if (copy_to_user(buf + done, virq->irq_data, virq->irq_len)) { + rc = -EFAULT; + break; + } + done += virq->irq_len; + list_del(&virq->node); + kfree(virq); + } + mutex_unlock(&eventq->mutex); + + return done == 0 ? rc : done; +} + +static const struct iommufd_eventq_ops iommufd_eventq_virq_ops = { + .read = &iommufd_eventq_virq_fops_read, +}; + /* Common Event Queue Functions */
static ssize_t iommufd_eventq_fops_read(struct file *filep, char __user *buf, @@ -472,3 +541,72 @@ int iommufd_eventq_iopf_alloc(struct iommufd_ucmd *ucmd)
return rc; } + +int iommufd_eventq_virq_alloc(struct iommufd_ucmd *ucmd) +{ + struct iommu_virq_alloc *cmd = ucmd->cmd; + struct iommufd_eventq_virq *eventq_virq; + struct iommufd_viommu *viommu; + int fdno; + int rc; + + if (cmd->flags || cmd->type == IOMMU_VIRQ_TYPE_NONE) + return -EOPNOTSUPP; + + viommu = iommufd_get_viommu(ucmd, cmd->viommu_id); + if (IS_ERR(viommu)) + return PTR_ERR(viommu); + down_write(&viommu->virqs_rwsem); + + if (iommufd_viommu_find_eventq_virq(viommu, cmd->type)) { + rc = -EEXIST; + goto out_unlock_virqs; + } + + eventq_virq = __iommufd_object_alloc( + ucmd->ictx, eventq_virq, IOMMUFD_OBJ_EVENTQ_VIRQ, common.obj); + if (IS_ERR(eventq_virq)) { + rc = PTR_ERR(eventq_virq); + goto out_unlock_virqs; + } + + eventq_virq->type = cmd->type; + eventq_virq->viommu = viommu; + refcount_inc(&viommu->obj.users); + list_add_tail(&eventq_virq->node, &viommu->virqs); + + fdno = iommufd_eventq_init(&eventq_virq->common, "[iommufd-viommu-irq]", + ucmd->ictx, &iommufd_eventq_virq_ops); + if (fdno < 0) { + rc = fdno; + goto out_abort; + } + + eventq_virq->irq_wq = alloc_workqueue("viommu_irq/%d", WQ_UNBOUND, 0, + eventq_virq->common.obj.id); + if (!eventq_virq->irq_wq) { + rc = -ENOMEM; + goto out_put_fdno; + } + + cmd->out_virq_id = eventq_virq->common.obj.id; + cmd->out_virq_fd = fdno; + + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + if (rc) + goto out_put_fdno; + + iommufd_object_finalize(ucmd->ictx, &eventq_virq->common.obj); + fd_install(fdno, eventq_virq->common.filep); + goto out_unlock_virqs; + +out_put_fdno: + put_unused_fd(fdno); + fput(eventq_virq->common.filep); +out_abort: + iommufd_object_abort_and_destroy(ucmd->ictx, &eventq_virq->common.obj); +out_unlock_virqs: + up_write(&viommu->virqs_rwsem); + iommufd_put_object(ucmd->ictx, &viommu->obj); + return rc; +} diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index 539c24ada6d0..89e8ac56f4ce 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -335,6 +335,8 @@ static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id), IOCTL_OP(IOMMU_FAULT_QUEUE_ALLOC, iommufd_eventq_iopf_alloc, struct iommu_fault_alloc, out_fault_fd), + IOCTL_OP(IOMMU_VIRQ_ALLOC, iommufd_eventq_virq_alloc, + struct iommu_virq_alloc, out_virq_fd), IOCTL_OP(IOMMU_GET_HW_INFO, iommufd_get_hw_info, struct iommu_hw_info, __reserved), IOCTL_OP(IOMMU_HWPT_ALLOC, iommufd_hwpt_alloc, struct iommu_hwpt_alloc, @@ -504,6 +506,10 @@ static const struct iommufd_object_ops iommufd_object_ops[] = { [IOMMUFD_OBJ_EVENTQ_IOPF] = { .destroy = iommufd_eventq_iopf_destroy, }, + [IOMMUFD_OBJ_EVENTQ_VIRQ] = { + .destroy = iommufd_eventq_virq_destroy, + .abort = iommufd_eventq_virq_abort, + }, [IOMMUFD_OBJ_VIOMMU] = { .destroy = iommufd_viommu_destroy, }, diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c index 69b88e8c7c26..075b6aed79bc 100644 --- a/drivers/iommu/iommufd/viommu.c +++ b/drivers/iommu/iommufd/viommu.c @@ -59,6 +59,8 @@ int iommufd_viommu_alloc_ioctl(struct iommufd_ucmd *ucmd) viommu->ictx = ucmd->ictx; viommu->hwpt = hwpt_paging; refcount_inc(&viommu->hwpt->common.obj.users); + INIT_LIST_HEAD(&viommu->virqs); + init_rwsem(&viommu->virqs_rwsem); /* * It is the most likely case that a physical IOMMU is unpluggable. A * pluggable IOMMU instance (if exists) is responsible for refcounting