drivers/xen/pvcalls-back.c

Source file repositories/reference/linux-study-clean/drivers/xen/pvcalls-back.c

File Facts

System
Linux kernel
Corpus path
drivers/xen/pvcalls-back.c
Extension
.c
Size
30633 bytes
Lines
1252
Domain
Driver Families
Bucket
drivers/xen
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

ret = sock_create(AF_INET, SOCK_STREAM, 0, &sock);
	if (ret < 0)
		goto out;
	ret = inet_stream_connect(sock, (struct sockaddr_unsized *)sa, req->u.connect.len, 0);
	if (ret < 0) {
		sock_release(sock);
		goto out;
	}

	map = pvcalls_new_active_socket(fedata,
					req->u.connect.id,
					req->u.connect.ref,
					req->u.connect.evtchn,
					sock);
	if (!map)
		ret = -EFAULT;

out:
	rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++);
	rsp->req_id = req->req_id;
	rsp->cmd = req->cmd;
	rsp->u.connect.id = req->u.connect.id;
	rsp->ret = ret;

	return 0;
}

static int pvcalls_back_release_active(struct xenbus_device *dev,
				       struct pvcalls_fedata *fedata,
				       struct sock_mapping *map)
{
	disable_irq(map->irq);
	if (map->sock->sk != NULL) {
		write_lock_bh(&map->sock->sk->sk_callback_lock);
		map->sock->sk->sk_user_data = NULL;
		map->sock->sk->sk_data_ready = map->saved_data_ready;
		write_unlock_bh(&map->sock->sk->sk_callback_lock);
	}

	atomic_set(&map->release, 1);
	flush_work(&map->ioworker.register_work);

	xenbus_unmap_ring_vfree(dev, map->bytes);
	xenbus_unmap_ring_vfree(dev, (void *)map->ring);
	unbind_from_irqhandler(map->irq, map);

	sock_release(map->sock);
	kfree(map);

	return 0;
}

static int pvcalls_back_release_passive(struct xenbus_device *dev,
					struct pvcalls_fedata *fedata,
					struct sockpass_mapping *mappass)
{
	if (mappass->sock->sk != NULL) {
		write_lock_bh(&mappass->sock->sk->sk_callback_lock);
		mappass->sock->sk->sk_user_data = NULL;
		mappass->sock->sk->sk_data_ready = mappass->saved_data_ready;
		write_unlock_bh(&mappass->sock->sk->sk_callback_lock);
	}
	sock_release(mappass->sock);
	destroy_workqueue(mappass->wq);
	kfree(mappass);

	return 0;
}

static int pvcalls_back_release(struct xenbus_device *dev,
				struct xen_pvcalls_request *req)
{
	struct pvcalls_fedata *fedata;
	struct sock_mapping *map, *n;
	struct sockpass_mapping *mappass;
	int ret = 0;
	struct xen_pvcalls_response *rsp;

	fedata = dev_get_drvdata(&dev->dev);

	down(&fedata->socket_lock);
	list_for_each_entry_safe(map, n, &fedata->socket_mappings, list) {
		if (map->id == req->u.release.id) {
			list_del(&map->list);
			up(&fedata->socket_lock);
			ret = pvcalls_back_release_active(dev, fedata, map);
			goto out;
		}
	}
	mappass = radix_tree_lookup(&fedata->socketpass_mappings,

Annotation

Implementation Notes