Allow a VIOMMU object to allocate VIRQ events. Each VIOMMU is allowed to
have multiple VIRQ events but they must not have a duplicated type.
Signed-off-by: Nicolin Chen <nicol...@nvidia.com>
---
drivers/iommu/iommufd/event.c | 136 ++++++++++++++++++++++++
drivers/iommu/iommufd/iommufd_private.h | 54 ++++++++++
drivers/iommu/iommufd/main.c | 5 +
drivers/iommu/iommufd/viommu.c | 2 +
include/uapi/linux/iommufd.h | 32 ++++++
5 files changed, 229 insertions(+)
diff --git a/drivers/iommu/iommufd/event.c b/drivers/iommu/iommufd/event.c
index 8fea142e1ac2..f10827ce9cbd 100644
--- a/drivers/iommu/iommufd/event.c
+++ b/drivers/iommu/iommufd/event.c
@@ -339,6 +339,67 @@ static const struct iommufd_event_ops
iommufd_event_iopf_ops = {
.write = &iommufd_event_iopf_fops_write,
};
+/* IOMMUFD_OBJ_EVENT_VIRQ Functions */
+
+void iommufd_event_virq_destroy(struct iommufd_object *obj)
+{
+ struct iommufd_event *event =
+ container_of(obj, struct iommufd_event, obj);
+ struct iommufd_event_virq *event_virq = to_event_virq(event);
+ struct iommufd_viommu_irq *virq, *next;
+
+ /*
+ * The iommufd object's reference count is zero at this point.
+ * We can be confident that no other threads are currently
+ * accessing this pointer. Therefore, acquiring the mutex here
+ * is unnecessary.
+ */
+ list_for_each_entry_safe(virq, next, &event->deliver, node) {
+ list_del(&virq->node);
+ kfree(virq);
+ }
+ destroy_workqueue(event_virq->irq_wq);
+ list_del(&event_virq->node);
+ refcount_dec(&event_virq->viommu->obj.users);
+}
+
+static ssize_t
+iommufd_event_virq_fops_read(struct iommufd_event *event,
+ char __user *buf, size_t count, loff_t *ppos)
+{
+ size_t done = 0;
+ int rc = 0;
+
+ if (*ppos)
+ return -ESPIPE;
+
+ mutex_lock(&event->mutex);
+ while (!list_empty(&event->deliver) && count > done) {
+ struct iommufd_viommu_irq *virq =
+ list_first_entry(&event->deliver,
+ struct iommufd_viommu_irq, node);
+ void *virq_data = (void *)virq + sizeof(*virq);
+
+ if (virq->irq_len > count - done)
+ break;
+
+ if (copy_to_user(buf + done, virq_data, virq->irq_len)) {
+ rc = -EFAULT;
+ break;
+ }
+ done += virq->irq_len;
+ list_del(&virq->node);
+ kfree(virq);
+ }
+ mutex_unlock(&event->mutex);
+
+ return done == 0 ? rc : done;
+}
+
+static const struct iommufd_event_ops iommufd_event_virq_ops = {
+ .read = &iommufd_event_virq_fops_read,
+};
+
/* Common Event Functions */
static ssize_t iommufd_event_fops_read(struct file *filep, char __user *buf,
@@ -475,3 +536,78 @@ int iommufd_event_iopf_alloc(struct iommufd_ucmd *ucmd)
return rc;
}
+
+int iommufd_event_virq_alloc(struct iommufd_ucmd *ucmd)
+{
+ struct iommu_virq_alloc *cmd = ucmd->cmd;
+ struct iommufd_event_virq *event_virq;
+ struct workqueue_struct *irq_wq;
+ struct iommufd_viommu *viommu;
+ int fdno;
+ int rc;
+
+ if (cmd->flags)
+ return -EOPNOTSUPP;
+ if (cmd->type == IOMMU_VIRQ_TYPE_NONE)
+ return -EINVAL;
+
+ 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_event_virq(viommu, cmd->type)) {
+ rc = -EEXIST;
+ goto out_unlock_virqs;
+ }
+
+ event_virq = __iommufd_object_alloc(ucmd->ictx, event_virq,
+ IOMMUFD_OBJ_EVENT_VIRQ, common.obj);
+ if (IS_ERR(event_virq)) {
+ rc = PTR_ERR(event_virq);
+ goto out_unlock_virqs;
+ }
+
+ irq_wq = alloc_workqueue("viommu_irq/%d", WQ_UNBOUND, 0,
+ event_virq->common.obj.id);
+ if (!irq_wq) {
+ rc = -ENOMEM;
+ goto out_abort;
+ }
+
+ rc = iommufd_event_init(&event_virq->common, "[iommufd-viommu-irq]",
+ ucmd->ictx, &fdno, &iommufd_event_virq_ops);
+ if (rc)
+ goto out_irq_wq;
+
+ event_virq->irq_wq = irq_wq;
+ event_virq->viommu = viommu;
+ event_virq->type = cmd->type;
+ cmd->out_virq_id = event_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, &event_virq->common.obj);
+
+ fd_install(fdno, event_virq->common.filep);
+
+ list_add_tail(&event_virq->node, &viommu->virqs);
+ refcount_inc(&viommu->obj.users);
+
+ goto out_unlock_virqs;
+out_put_fdno:
+ put_unused_fd(fdno);
+ fput(event_virq->common.filep);
+ iommufd_event_deinit(&event_virq->common);
+out_irq_wq:
+ destroy_workqueue(irq_wq);
+out_abort:
+ iommufd_object_abort_and_destroy(ucmd->ictx, &event_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/iommufd_private.h
b/drivers/iommu/iommufd/iommufd_private.h
index c22d72c981c7..be1f1813672e 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -133,6 +133,7 @@ enum iommufd_object_type {
IOMMUFD_OBJ_IOAS,
IOMMUFD_OBJ_ACCESS,
IOMMUFD_OBJ_EVENT_IOPF,
+ IOMMUFD_OBJ_EVENT_VIRQ,
IOMMUFD_OBJ_VIOMMU,
#ifdef CONFIG_IOMMUFD_TEST
IOMMUFD_OBJ_SELFTEST,
@@ -567,6 +568,43 @@ static inline int iommufd_hwpt_replace_device(struct
iommufd_device *idev,
return iommu_group_replace_domain(idev->igroup->group, hwpt->domain);
}
+struct iommufd_event_virq {
+ struct iommufd_event common;
+ struct iommufd_viommu *viommu;
+ struct workqueue_struct *irq_wq;
+ struct list_head node;
+
+ unsigned int type;
+};
+
+static inline struct iommufd_event_virq *
+to_event_virq(struct iommufd_event *event)
+{
+ return container_of(event, struct iommufd_event_virq, common);
+}
+
+static inline struct iommufd_event_virq *
+iommufd_get_event_virq(struct iommufd_ucmd *ucmd, u32 id)
+{
+ return container_of(iommufd_get_object(ucmd->ictx, id,
+ IOMMUFD_OBJ_EVENT_VIRQ),
+ struct iommufd_event_virq, common.obj);
+}
+
+int iommufd_event_virq_alloc(struct iommufd_ucmd *ucmd);
+void iommufd_event_virq_destroy(struct iommufd_object *obj);
+
+struct iommufd_viommu_irq {
+ struct iommufd_event_virq *event_virq;
+ struct list_head node;
+ ssize_t irq_len;
+};
+
+static inline int iommufd_event_virq_handler(struct iommufd_viommu_irq *virq)
+{
+ return iommufd_event_notify(&virq->event_virq->common, &virq->node);
+}
+
struct iommufd_viommu {
struct iommufd_object obj;
struct iommufd_ctx *ictx;
@@ -575,6 +613,8 @@ struct iommufd_viommu {
/* The locking order is vdev_ids_rwsem -> igroup::lock */
struct rw_semaphore vdev_ids_rwsem;
struct xarray vdev_ids;
+ struct rw_semaphore virqs_rwsem;
+ struct list_head virqs;
const struct iommufd_viommu_ops *ops;
@@ -595,6 +635,20 @@ iommufd_get_viommu(struct iommufd_ucmd *ucmd, u32 id)
struct iommufd_viommu, obj);
}
+static inline struct iommufd_event_virq *
+iommufd_viommu_find_event_virq(struct iommufd_viommu *viommu, u32 type)
+{
+ struct iommufd_event_virq *event_virq, *next;
+
+ lockdep_assert_held(&viommu->virqs_rwsem);
+
+ list_for_each_entry_safe(event_virq, next, &viommu->virqs, node) {
+ if (event_virq->type == type)
+ return event_virq;
+ }
+ return NULL;
+}
+
int iommufd_viommu_alloc_ioctl(struct iommufd_ucmd *ucmd);
void iommufd_viommu_destroy(struct iommufd_object *obj);
int iommufd_viommu_set_vdev_id(struct iommufd_ucmd *ucmd);
diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
index 015f492afab1..22381ba031b5 100644
--- a/drivers/iommu/iommufd/main.c
+++ b/drivers/iommu/iommufd/main.c
@@ -361,6 +361,8 @@ 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_event_iopf_alloc,
struct iommu_fault_alloc, out_fault_fd),
+ IOCTL_OP(IOMMU_VIRQ_ALLOC, iommufd_event_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,
@@ -528,6 +530,9 @@ static const struct iommufd_object_ops iommufd_object_ops[]
= {
[IOMMUFD_OBJ_EVENT_IOPF] = {
.destroy = iommufd_event_iopf_destroy,
},
+ [IOMMUFD_OBJ_EVENT_VIRQ] = {
+ .destroy = iommufd_event_virq_destroy,
+ },
[IOMMUFD_OBJ_VIOMMU] = {
.destroy = iommufd_viommu_destroy,
},
diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c
index a4ba8bff4a26..9adc9c62ada9 100644
--- a/drivers/iommu/iommufd/viommu.c
+++ b/drivers/iommu/iommufd/viommu.c
@@ -67,6 +67,8 @@ int iommufd_viommu_alloc_ioctl(struct iommufd_ucmd *ucmd)
xa_init(&viommu->vdev_ids);
init_rwsem(&viommu->vdev_ids_rwsem);
+ INIT_LIST_HEAD(&viommu->virqs);
+ init_rwsem(&viommu->virqs_rwsem);
refcount_inc(&viommu->hwpt->common.obj.users);
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 0d973486b604..f9ec07efed8d 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -54,6 +54,7 @@ enum {
IOMMUFD_CMD_VIOMMU_ALLOC = 0x8f,
IOMMUFD_CMD_VIOMMU_SET_VDEV_ID = 0x90,
IOMMUFD_CMD_VIOMMU_UNSET_VDEV_ID = 0x91,
+ IOMMUFD_CMD_VIRQ_ALLOC = 0x92,
};
/**
@@ -951,4 +952,35 @@ struct iommu_viommu_unset_vdev_id {
__aligned_u64 vdev_id;
};
#define IOMMU_VIOMMU_UNSET_VDEV_ID _IO(IOMMUFD_TYPE,
IOMMUFD_CMD_VIOMMU_UNSET_VDEV_ID)
+
+/**
+ * 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: viommu 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 VIRQ
+ * @out_fault_fd: The fd of the new VIRQ
+ *
+ * Explicitly allocate a virtual IRQ handler for a VIOMMU. A VIOMMU can have
+ * multiple FDs for different @type, but is confined to have only 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
--
2.43.0
