1 files changed, 553 insertions, 7 deletions

diff --git a/drivers/infiniband/hw/mlx5/devx.c b/drivers/infiniband/hw/mlx5/devx.c
index a9affc905bfa..9c21cafc44a6 100644
--- a/drivers/infiniband/hw/mlx5/devx.c
+++ b/drivers/infiniband/hw/mlx5/devx.c
@@ -14,6 +14,7 @@
 #include <linux/mlx5/driver.h>
 #include <linux/mlx5/fs.h>
 #include "mlx5_ib.h"
+#include <linux/xarray.h>
 
 #define UVERBS_MODULE_NAME mlx5_ib
 #include <rdma/uverbs_named_ioctl.h>
@@ -33,6 +34,40 @@ struct devx_async_data {
 	struct mlx5_ib_uapi_devx_async_cmd_hdr hdr;
 };
 
+/* first level XA value data structure */
+struct devx_event {
+	struct xarray object_ids; /* second XA level, Key = object id */
+	struct list_head unaffiliated_list;
+};
+
+/* second level XA value data structure */
+struct devx_obj_event {
+	struct rcu_head rcu;
+	struct list_head obj_sub_list;
+};
+
+struct devx_event_subscription {
+	struct list_head file_list; /* headed in ev_file->
+				     * subscribed_events_list
+				     */
+	struct list_head xa_list; /* headed in devx_event->unaffiliated_list or
+				   * devx_obj_event->obj_sub_list
+				   */
+	struct list_head obj_list; /* headed in devx_object */
+	struct list_head event_list; /* headed in ev_file->event_list or in
+				      * temp list via subscription
+				      */
+
+	u8 is_cleaned:1;
+	u32 xa_key_level1;
+	u32 xa_key_level2;
+	struct rcu_head	rcu;
+	u64 cookie;
+	struct devx_async_event_file *ev_file;
+	struct file *filp; /* Upon hot unplug we need a direct access to */
+	struct eventfd_ctx *eventfd;
+};
+
 struct devx_async_event_file {
 	struct ib_uobject uobj;
 	/* Head of events that are subscribed to this FD */
@@ -55,6 +90,7 @@ struct devx_obj {
 		struct mlx5_ib_devx_mr	devx_mr;
 		struct mlx5_core_dct	core_dct;
 	};
+	struct list_head event_sub; /* holds devx_event_subscription entries */
 };
 
 struct devx_umem {
@@ -160,6 +196,104 @@ bool mlx5_ib_devx_is_flow_counter(void *obj, u32 *counter_id)
 	return false;
 }
 
+static bool is_legacy_unaffiliated_event_num(u16 event_num)
+{
+	switch (event_num) {
+	case MLX5_EVENT_TYPE_PORT_CHANGE:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool is_legacy_obj_event_num(u16 event_num)
+{
+	switch (event_num) {
+	case MLX5_EVENT_TYPE_PATH_MIG:
+	case MLX5_EVENT_TYPE_COMM_EST:
+	case MLX5_EVENT_TYPE_SQ_DRAINED:
+	case MLX5_EVENT_TYPE_SRQ_LAST_WQE:
+	case MLX5_EVENT_TYPE_SRQ_RQ_LIMIT:
+	case MLX5_EVENT_TYPE_CQ_ERROR:
+	case MLX5_EVENT_TYPE_WQ_CATAS_ERROR:
+	case MLX5_EVENT_TYPE_PATH_MIG_FAILED:
+	case MLX5_EVENT_TYPE_WQ_INVAL_REQ_ERROR:
+	case MLX5_EVENT_TYPE_WQ_ACCESS_ERROR:
+	case MLX5_EVENT_TYPE_SRQ_CATAS_ERROR:
+	case MLX5_EVENT_TYPE_DCT_DRAINED:
+	case MLX5_EVENT_TYPE_COMP:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static u16 get_legacy_obj_type(u16 opcode)
+{
+	switch (opcode) {
+	case MLX5_CMD_OP_CREATE_RQ:
+		return MLX5_EVENT_QUEUE_TYPE_RQ;
+	case MLX5_CMD_OP_CREATE_QP:
+		return MLX5_EVENT_QUEUE_TYPE_QP;
+	case MLX5_CMD_OP_CREATE_SQ:
+		return MLX5_EVENT_QUEUE_TYPE_SQ;
+	case MLX5_CMD_OP_CREATE_DCT:
+		return MLX5_EVENT_QUEUE_TYPE_DCT;
+	default:
+		return 0;
+	}
+}
+
+static u16 get_dec_obj_type(struct devx_obj *obj, u16 event_num)
+{
+	u16 opcode;
+
+	opcode = (obj->obj_id >> 32) & 0xffff;
+
+	if (is_legacy_obj_event_num(event_num))
+		return get_legacy_obj_type(opcode);
+
+	switch (opcode) {
+	case MLX5_CMD_OP_CREATE_GENERAL_OBJECT:
+		return (obj->obj_id >> 48);
+	case MLX5_CMD_OP_CREATE_RQ:
+		return MLX5_OBJ_TYPE_RQ;
+	case MLX5_CMD_OP_CREATE_QP:
+		return MLX5_OBJ_TYPE_QP;
+	case MLX5_CMD_OP_CREATE_SQ:
+		return MLX5_OBJ_TYPE_SQ;
+	case MLX5_CMD_OP_CREATE_DCT:
+		return MLX5_OBJ_TYPE_DCT;
+	case MLX5_CMD_OP_CREATE_TIR:
+		return MLX5_OBJ_TYPE_TIR;
+	case MLX5_CMD_OP_CREATE_TIS:
+		return MLX5_OBJ_TYPE_TIS;
+	case MLX5_CMD_OP_CREATE_PSV:
+		return MLX5_OBJ_TYPE_PSV;
+	case MLX5_OBJ_TYPE_MKEY:
+		return MLX5_OBJ_TYPE_MKEY;
+	case MLX5_CMD_OP_CREATE_RMP:
+		return MLX5_OBJ_TYPE_RMP;
+	case MLX5_CMD_OP_CREATE_XRC_SRQ:
+		return MLX5_OBJ_TYPE_XRC_SRQ;
+	case MLX5_CMD_OP_CREATE_XRQ:
+		return MLX5_OBJ_TYPE_XRQ;
+	case MLX5_CMD_OP_CREATE_RQT:
+		return MLX5_OBJ_TYPE_RQT;
+	case MLX5_CMD_OP_ALLOC_FLOW_COUNTER:
+		return MLX5_OBJ_TYPE_FLOW_COUNTER;
+	case MLX5_CMD_OP_CREATE_CQ:
+		return MLX5_OBJ_TYPE_CQ;
+	default:
+		return 0;
+	}
+}
+
+static u32 get_dec_obj_id(u64 obj_id)
+{
+	return (obj_id & 0xffffffff);
+}
+
 /*
  * As the obj_id in the firmware is not globally unique the object type
  * must be considered upon checking for a valid object id.
@@ -1126,14 +1260,47 @@ static void devx_cleanup_mkey(struct devx_obj *obj)
 		 mlx5_base_mkey(obj->devx_mr.mmkey.key));
 }
 
+static void devx_cleanup_subscription(struct mlx5_ib_dev *dev,
+				      struct devx_event_subscription *sub)
+{
+	struct devx_event *event;
+	struct devx_obj_event *xa_val_level2;
+
+	if (sub->is_cleaned)
+		return;
+
+	sub->is_cleaned = 1;
+	list_del_rcu(&sub->xa_list);
+
+	if (list_empty(&sub->obj_list))
+		return;
+
+	list_del_rcu(&sub->obj_list);
+	/* check whether key level 1 for this obj_sub_list is empty */
+	event = xa_load(&dev->devx_event_table.event_xa,
+			sub->xa_key_level1);
+	WARN_ON(!event);
+
+	xa_val_level2 = xa_load(&event->object_ids, sub->xa_key_level2);
+	if (list_empty(&xa_val_level2->obj_sub_list)) {
+		xa_erase(&event->object_ids,
+			 sub->xa_key_level2);
+		kfree_rcu(xa_val_level2, rcu);
+	}
+}
+
 static int devx_obj_cleanup(struct ib_uobject *uobject,
 			    enum rdma_remove_reason why,
 			    struct uverbs_attr_bundle *attrs)
 {
 	u32 out[MLX5_ST_SZ_DW(general_obj_out_cmd_hdr)];
+	struct mlx5_devx_event_table *devx_event_table;
 	struct devx_obj *obj = uobject->object;
+	struct devx_event_subscription *sub_entry, *tmp;
+	struct mlx5_ib_dev *dev;
 	int ret;
 
+	dev = mlx5_udata_to_mdev(&attrs->driver_udata);
 	if (obj->flags & DEVX_OBJ_FLAGS_INDIRECT_MKEY)
 		devx_cleanup_mkey(obj);
 
@@ -1145,10 +1312,14 @@ static int devx_obj_cleanup(struct ib_uobject *uobject,
 	if (ib_is_destroy_retryable(ret, why, uobject))
 		return ret;
 
-	if (obj->flags & DEVX_OBJ_FLAGS_INDIRECT_MKEY) {
-		struct mlx5_ib_dev *dev =
-			mlx5_udata_to_mdev(&attrs->driver_udata);
+	devx_event_table = &dev->devx_event_table;
+
+	mutex_lock(&devx_event_table->event_xa_lock);
+	list_for_each_entry_safe(sub_entry, tmp, &obj->event_sub, obj_list)
+		devx_cleanup_subscription(dev, sub_entry);
+	mutex_unlock(&devx_event_table->event_xa_lock);
 
+	if (obj->flags & DEVX_OBJ_FLAGS_INDIRECT_MKEY) {
 		call_srcu(&dev->mr_srcu, &obj->devx_mr.rcu,
 			  devx_free_indirect_mkey);
 		return ret;
@@ -1220,6 +1391,7 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_CREATE)(
 
 	uobj->object = obj;
 	obj->mdev = dev->mdev;
+	INIT_LIST_HEAD(&obj->event_sub);
 	devx_obj_build_destroy_cmd(cmd_in, cmd_out, obj->dinbox, &obj->dinlen,
 				   &obj_id);
 	WARN_ON(obj->dinlen > MLX5_MAX_DESTROY_INBOX_SIZE_DW * sizeof(u32));
@@ -1404,6 +1576,7 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_ASYNC_EVENT_FD_ALLOC)(
 		ev_file->omit_data = 1;
 	INIT_LIST_HEAD(&ev_file->subscribed_events_list);
 	ev_file->dev = dev;
+	get_device(&dev->ib_dev.dev);
 	return 0;
 }
 
@@ -1516,6 +1689,331 @@ sub_bytes:
 	return err;
 }
 
+static void
+subscribe_event_xa_dealloc(struct mlx5_devx_event_table *devx_event_table,
+			   u32 key_level1,
+			   bool is_level2,
+			   u32 key_level2)
+{
+	struct devx_event *event;
+	struct devx_obj_event *xa_val_level2;
+
+	/* Level 1 is valid for future use, no need to free */
+	if (!is_level2)
+		return;
+
+	event = xa_load(&devx_event_table->event_xa, key_level1);
+	WARN_ON(!event);
+
+	xa_val_level2 = xa_load(&event->object_ids,
+				key_level2);
+	if (list_empty(&xa_val_level2->obj_sub_list)) {
+		xa_erase(&event->object_ids,
+			 key_level2);
+		kfree_rcu(xa_val_level2, rcu);
+	}
+}
+
+static int
+subscribe_event_xa_alloc(struct mlx5_devx_event_table *devx_event_table,
+			 u32 key_level1,
+			 bool is_level2,
+			 u32 key_level2)
+{
+	struct devx_obj_event *obj_event;
+	struct devx_event *event;
+	int err;
+
+	event = xa_load(&devx_event_table->event_xa, key_level1);
+	if (!event) {
+		event = kzalloc(sizeof(*event), GFP_KERNEL);
+		if (!event)
+			return -ENOMEM;
+
+		INIT_LIST_HEAD(&event->unaffiliated_list);
+		xa_init(&event->object_ids);
+
+		err = xa_insert(&devx_event_table->event_xa,
+				key_level1,
+				event,
+				GFP_KERNEL);
+		if (err) {
+			kfree(event);
+			return err;
+		}
+	}
+
+	if (!is_level2)
+		return 0;
+
+	obj_event = xa_load(&event->object_ids, key_level2);
+	if (!obj_event) {
+		obj_event = kzalloc(sizeof(*obj_event), GFP_KERNEL);
+		if (!obj_event)
+			/* Level1 is valid for future use, no need to free */
+			return -ENOMEM;
+
+		err = xa_insert(&event->object_ids,
+				key_level2,
+				obj_event,
+				GFP_KERNEL);
+		if (err)
+			return err;
+		INIT_LIST_HEAD(&obj_event->obj_sub_list);
+	}
+
+	return 0;
+}
+
+static bool is_valid_events_legacy(int num_events, u16 *event_type_num_list,
+				   struct devx_obj *obj)
+{
+	int i;
+
+	for (i = 0; i < num_events; i++) {
+		if (obj) {
+			if (!is_legacy_obj_event_num(event_type_num_list[i]))
+				return false;
+		} else if (!is_legacy_unaffiliated_event_num(
+				event_type_num_list[i])) {
+			return false;
+		}
+	}
+
+	return true;
+}
+
+#define MAX_SUPP_EVENT_NUM 255
+static bool is_valid_events(struct mlx5_core_dev *dev,
+			    int num_events, u16 *event_type_num_list,
+			    struct devx_obj *obj)
+{
+	__be64 *aff_events;
+	__be64 *unaff_events;
+	int mask_entry;
+	int mask_bit;
+	int i;
+
+	if (MLX5_CAP_GEN(dev, event_cap)) {
+		aff_events = MLX5_CAP_DEV_EVENT(dev,
+						user_affiliated_events);
+		unaff_events = MLX5_CAP_DEV_EVENT(dev,
+						  user_unaffiliated_events);
+	} else {
+		return is_valid_events_legacy(num_events, event_type_num_list,
+					      obj);
+	}
+
+	for (i = 0; i < num_events; i++) {
+		if (event_type_num_list[i] > MAX_SUPP_EVENT_NUM)
+			return false;
+
+		mask_entry = event_type_num_list[i] / 64;
+		mask_bit = event_type_num_list[i] % 64;
+
+		if (obj) {
+			/* CQ completion */
+			if (event_type_num_list[i] == 0)
+				continue;
+
+			if (!(be64_to_cpu(aff_events[mask_entry]) &
+					(1ull << mask_bit)))
+				return false;
+
+			continue;
+		}
+
+		if (!(be64_to_cpu(unaff_events[mask_entry]) &
+				(1ull << mask_bit)))
+			return false;
+	}
+
+	return true;
+}
+
+#define MAX_NUM_EVENTS 16
+static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct ib_uobject *devx_uobj = uverbs_attr_get_uobject(
+				attrs,
+				MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_OBJ_HANDLE);
+	struct mlx5_ib_ucontext *c = rdma_udata_to_drv_context(
+		&attrs->driver_udata, struct mlx5_ib_ucontext, ibucontext);
+	struct mlx5_ib_dev *dev = to_mdev(c->ibucontext.device);
+	struct ib_uobject *fd_uobj;
+	struct devx_obj *obj = NULL;
+	struct devx_async_event_file *ev_file;
+	struct mlx5_devx_event_table *devx_event_table = &dev->devx_event_table;
+	u16 *event_type_num_list;
+	struct devx_event_subscription *event_sub, *tmp_sub;
+	struct list_head sub_list;
+	int redirect_fd;
+	bool use_eventfd = false;
+	int num_events;
+	int num_alloc_xa_entries = 0;
+	u16 obj_type = 0;
+	u64 cookie = 0;
+	u32 obj_id = 0;
+	int err;
+	int i;
+
+	if (!c->devx_uid)
+		return -EINVAL;
+
+	if (!IS_ERR(devx_uobj)) {
+		obj = (struct devx_obj *)devx_uobj->object;
+		if (obj)
+			obj_id = get_dec_obj_id(obj->obj_id);
+	}
+
+	fd_uobj = uverbs_attr_get_uobject(attrs,
+				MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_FD_HANDLE);
+	if (IS_ERR(fd_uobj))
+		return PTR_ERR(fd_uobj);
+
+	ev_file = container_of(fd_uobj, struct devx_async_event_file,
+			       uobj);
+
+	if (uverbs_attr_is_valid(attrs,
+				 MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_FD_NUM)) {
+		err = uverbs_copy_from(&redirect_fd, attrs,
+			       MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_FD_NUM);
+		if (err)
+			return err;
+
+		use_eventfd = true;
+	}
+
+	if (uverbs_attr_is_valid(attrs,
+				 MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_COOKIE)) {
+		if (use_eventfd)
+			return -EINVAL;
+
+		err = uverbs_copy_from(&cookie, attrs,
+				MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_COOKIE);
+		if (err)
+			return err;
+	}
+
+	num_events = uverbs_attr_ptr_get_array_size(
+		attrs, MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_TYPE_NUM_LIST,
+		sizeof(u16));
+
+	if (num_events < 0)
+		return num_events;
+
+	if (num_events > MAX_NUM_EVENTS)
+		return -EINVAL;
+
+	event_type_num_list = uverbs_attr_get_alloced_ptr(attrs,
+			MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_TYPE_NUM_LIST);
+
+	if (!is_valid_events(dev->mdev, num_events, event_type_num_list, obj))
+		return -EINVAL;
+
+	INIT_LIST_HEAD(&sub_list);
+
+	/* Protect from concurrent subscriptions to same XA entries to allow
+	 * both to succeed
+	 */
+	mutex_lock(&devx_event_table->event_xa_lock);
+	for (i = 0; i < num_events; i++) {
+		u32 key_level1;
+
+		if (obj)
+			obj_type = get_dec_obj_type(obj,
+						    event_type_num_list[i]);
+		key_level1 = event_type_num_list[i] | obj_type << 16;
+
+		err = subscribe_event_xa_alloc(devx_event_table,
+					       key_level1,
+					       obj,
+					       obj_id);
+		if (err)
+			goto err;
+
+		num_alloc_xa_entries++;
+		event_sub = kzalloc(sizeof(*event_sub), GFP_KERNEL);
+		if (!event_sub)
+			goto err;
+
+		list_add_tail(&event_sub->event_list, &sub_list);
+		if (use_eventfd) {
+			event_sub->eventfd =
+				eventfd_ctx_fdget(redirect_fd);
+
+			if (IS_ERR(event_sub)) {
+				err = PTR_ERR(event_sub->eventfd);
+				event_sub->eventfd = NULL;
+				goto err;
+			}
+		}
+
+		event_sub->cookie = cookie;
+		event_sub->ev_file = ev_file;
+		event_sub->filp = fd_uobj->object;
+		/* May be needed upon cleanup the devx object/subscription */
+		event_sub->xa_key_level1 = key_level1;
+		event_sub->xa_key_level2 = obj_id;
+		INIT_LIST_HEAD(&event_sub->obj_list);
+	}
+
+	/* Once all the allocations and the XA data insertions were done we
+	 * can go ahead and add all the subscriptions to the relevant lists
+	 * without concern of a failure.
+	 */
+	list_for_each_entry_safe(event_sub, tmp_sub, &sub_list, event_list) {
+		struct devx_event *event;
+		struct devx_obj_event *obj_event;
+
+		list_del_init(&event_sub->event_list);
+
+		spin_lock_irq(&ev_file->lock);
+		list_add_tail_rcu(&event_sub->file_list,
+				  &ev_file->subscribed_events_list);
+		spin_unlock_irq(&ev_file->lock);
+
+		event = xa_load(&devx_event_table->event_xa,
+				event_sub->xa_key_level1);
+		WARN_ON(!event);
+
+		if (!obj) {
+			list_add_tail_rcu(&event_sub->xa_list,
+					  &event->unaffiliated_list);
+			continue;
+		}
+
+		obj_event = xa_load(&event->object_ids, obj_id);
+		WARN_ON(!obj_event);
+		list_add_tail_rcu(&event_sub->xa_list,
+				  &obj_event->obj_sub_list);
+		list_add_tail_rcu(&event_sub->obj_list,
+				  &obj->event_sub);
+	}
+
+	mutex_unlock(&devx_event_table->event_xa_lock);
+	return 0;
+
+err:
+	list_for_each_entry_safe(event_sub, tmp_sub, &sub_list, event_list) {
+		list_del(&event_sub->event_list);
+
+		subscribe_event_xa_dealloc(devx_event_table,
+					   event_sub->xa_key_level1,
+					   obj,
+					   obj_id);
+
+		if (event_sub->eventfd)
+			eventfd_ctx_put(event_sub->eventfd);
+
+		kfree(event_sub);
+	}
+
+	mutex_unlock(&devx_event_table->event_xa_lock);
+	return err;
+}
+
 static int devx_umem_get(struct mlx5_ib_dev *dev, struct ib_ucontext *ucontext,
 			 struct uverbs_attr_bundle *attrs,
 			 struct devx_umem *obj)
@@ -1682,14 +2180,21 @@ void mlx5_ib_devx_init_event_table(struct mlx5_ib_dev *dev)
 void mlx5_ib_devx_cleanup_event_table(struct mlx5_ib_dev *dev)
 {
 	struct mlx5_devx_event_table *table = &dev->devx_event_table;
+	struct devx_event_subscription *sub, *tmp;
+	struct devx_event *event;
 	void *entry;
 	unsigned long id;
 
 	mlx5_eq_notifier_unregister(dev->mdev, &table->devx_nb);
-
-	xa_for_each(&table->event_xa, id, entry)
+	mutex_lock(&dev->devx_event_table.event_xa_lock);
+	xa_for_each(&table->event_xa, id, entry) {
+		event = entry;
+		list_for_each_entry_safe(sub, tmp, &event->unaffiliated_list,
+					 xa_list)
+			devx_cleanup_subscription(dev, sub);
 		kfree(entry);
-
+	}
+	mutex_unlock(&dev->devx_event_table.event_xa_lock);
 	xa_destroy(&table->event_xa);
 }
 
@@ -1805,7 +2310,26 @@ static __poll_t devx_async_event_poll(struct file *filp,
 
 static int devx_async_event_close(struct inode *inode, struct file *filp)
 {
+	struct devx_async_event_file *ev_file = filp->private_data;
+	struct devx_event_subscription *event_sub, *event_sub_tmp;
+
+	mutex_lock(&ev_file->dev->devx_event_table.event_xa_lock);
+	/* delete the subscriptions which are related to this FD */
+	list_for_each_entry_safe(event_sub, event_sub_tmp,
+				 &ev_file->subscribed_events_list, file_list) {
+		devx_cleanup_subscription(ev_file->dev, event_sub);
+		if (event_sub->eventfd)
+			eventfd_ctx_put(event_sub->eventfd);
+
+		list_del_rcu(&event_sub->file_list);
+		/* subscription may not be used by the read API any more */
+		kfree_rcu(event_sub, rcu);
+	}
+
+	mutex_unlock(&ev_file->dev->devx_event_table.event_xa_lock);
+
 	uverbs_close_fd(filp);
+	put_device(&ev_file->dev->ib_dev.dev);
 	return 0;
 }
 
@@ -1973,10 +2497,32 @@ DECLARE_UVERBS_NAMED_METHOD(
 		UVERBS_ATTR_TYPE(u64),
 		UA_MANDATORY));
 
+DECLARE_UVERBS_NAMED_METHOD(
+	MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT,
+	UVERBS_ATTR_FD(MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_FD_HANDLE,
+		MLX5_IB_OBJECT_DEVX_ASYNC_EVENT_FD,
+		UVERBS_ACCESS_READ,
+		UA_MANDATORY),
+	UVERBS_ATTR_IDR(MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_OBJ_HANDLE,
+		MLX5_IB_OBJECT_DEVX_OBJ,
+		UVERBS_ACCESS_READ,
+		UA_OPTIONAL),
+	UVERBS_ATTR_PTR_IN(MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_TYPE_NUM_LIST,
+		UVERBS_ATTR_MIN_SIZE(sizeof(u16)),
+		UA_MANDATORY,
+		UA_ALLOC_AND_COPY),
+	UVERBS_ATTR_PTR_IN(MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_COOKIE,
+		UVERBS_ATTR_TYPE(u64),
+		UA_OPTIONAL),
+	UVERBS_ATTR_PTR_IN(MLX5_IB_ATTR_DEVX_SUBSCRIBE_EVENT_FD_NUM,
+		UVERBS_ATTR_TYPE(u32),
+		UA_OPTIONAL));
+
 DECLARE_UVERBS_GLOBAL_METHODS(MLX5_IB_OBJECT_DEVX,
 			      &UVERBS_METHOD(MLX5_IB_METHOD_DEVX_OTHER),
 			      &UVERBS_METHOD(MLX5_IB_METHOD_DEVX_QUERY_UAR),
-			      &UVERBS_METHOD(MLX5_IB_METHOD_DEVX_QUERY_EQN));
+			      &UVERBS_METHOD(MLX5_IB_METHOD_DEVX_QUERY_EQN),
+			      &UVERBS_METHOD(MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT));
 
 DECLARE_UVERBS_NAMED_OBJECT(MLX5_IB_OBJECT_DEVX_OBJ,
 			    UVERBS_TYPE_ALLOC_IDR(devx_obj_cleanup),