Changes in uspace/srv/devman/main.c [79ae36dd:f278930] in mainline

File:

• uspace/srv/devman/main.c (modified) (30 diffs)

uspace/srv/devman/main.c

@@ -56 +56 @@
 #include <ipc/driver.h>
 #include <thread.h>
-#include <devmap.h>
+#include <loc.h>
 
 #include "devman.h"
@@ -64 +64 @@
 static driver_list_t drivers_list;
 static dev_tree_t device_tree;
-static class_list_t class_list;
+
+static int init_running_drv(void *drv);
 
 /** Register running driver. */
-static driver_t *devman_driver_register(void)
-{
-        ipc_call_t icall;
-        ipc_callid_t iid;
+static driver_t *devman_driver_register(ipc_callid_t callid, ipc_call_t *call)
+{
         driver_t *driver = NULL;
+        char *drv_name = NULL;
 
         log_msg(LVL_DEBUG, "devman_driver_register");
-        
-        iid = async_get_call(&icall);
-        if (IPC_GET_IMETHOD(icall) != DEVMAN_DRIVER_REGISTER) {
-                async_answer_0(iid, EREFUSED);
-                return NULL;
-        }
-        
-        char *drv_name = NULL;
         
         /* Get driver name. */
         int rc = async_data_write_accept((void **) &drv_name, true, 0, 0, 0, 0);
         if (rc != EOK) {
-                async_answer_0(iid, rc);
+                async_answer_0(callid, rc);
                 return NULL;
         }
@@ -99 +91 @@
                 free(drv_name);
                 drv_name = NULL;
-                async_answer_0(iid, ENOENT);
+                async_answer_0(callid, ENOENT);
                 return NULL;
         }
@@ -113 +105 @@
                     driver->name);
                 fibril_mutex_unlock(&driver->driver_mutex);
-                async_answer_0(iid, EEXISTS);
+                async_answer_0(callid, EEXISTS);
                 return NULL;
         }
@@ -135 +127 @@
         log_msg(LVL_DEBUG, "Creating connection to the `%s' driver.",
             driver->name);
-        driver->sess = async_callback_receive(EXCHANGE_SERIALIZE);
+        driver->sess = async_callback_receive(EXCHANGE_PARALLEL);
         if (!driver->sess) {
                 fibril_mutex_unlock(&driver->driver_mutex);
-                async_answer_0(iid, ENOTSUP);
+                async_answer_0(callid, ENOTSUP);
                 return NULL;
         }
-        
-        fibril_mutex_unlock(&driver->driver_mutex);
+        /* FIXME: Work around problem with callback sessions */
+        async_sess_args_set(driver->sess, DRIVER_DEVMAN, 0, 0);
         
         log_msg(LVL_NOTE,
@@ -148 +140 @@
             driver->name);
         
-        async_answer_0(iid, EOK);
-        
+        /*
+         * Initialize the driver as running (e.g. pass assigned devices to it)
+         * in a separate fibril; the separate fibril is used to enable the
+         * driver to use devman service during the driver's initialization.
+         */
+        fid_t fid = fibril_create(init_running_drv, driver);
+        if (fid == 0) {
+                log_msg(LVL_ERROR, "Failed to create initialization fibril " \
+                    "for driver `%s'.", driver->name);
+                fibril_mutex_unlock(&driver->driver_mutex);
+                async_answer_0(callid, ENOMEM);
+                return NULL;
+        }
+        
+        fibril_add_ready(fid);
+        fibril_mutex_unlock(&driver->driver_mutex);
+        
+        async_answer_0(callid, EOK);
         return driver;
 }
@@ -226 +234 @@
         dev_node_t *dev_node = (dev_node_t *) arg;
         assign_driver(dev_node, &drivers_list, &device_tree);
+
+        /* Delete one reference we got from the caller. */
+        dev_del_ref(dev_node);
         return EOK;
 }
 
-/** Handle function registration.
- *
- * Child devices are registered by their parent's device driver.
- */
-static void devman_add_function(ipc_callid_t callid, ipc_call_t *call)
-{
-        fun_type_t ftype = (fun_type_t) IPC_GET_ARG1(*call);
-        devman_handle_t dev_handle = IPC_GET_ARG2(*call);
-        sysarg_t match_count = IPC_GET_ARG3(*call);
-        dev_tree_t *tree = &device_tree;
-        
-        fibril_rwlock_write_lock(&tree->rwlock);
-
-        dev_node_t *dev = NULL;
-        dev_node_t *pdev = find_dev_node_no_lock(&device_tree, dev_handle);
-        
-        if (pdev == NULL) {
-                fibril_rwlock_write_unlock(&tree->rwlock);
-                async_answer_0(callid, ENOENT);
-                return;
-        }
-        
-        if (ftype != fun_inner && ftype != fun_exposed) {
-                /* Unknown function type */
-                log_msg(LVL_ERROR, 
-                    "Unknown function type %d provided by driver.",
-                    (int) ftype);
-
-                fibril_rwlock_write_unlock(&tree->rwlock);
-                async_answer_0(callid, EINVAL);
-                return;
-        }
-        
-        char *fun_name = NULL;
-        int rc = async_data_write_accept((void **)&fun_name, true, 0, 0, 0, 0);
-        if (rc != EOK) {
-                fibril_rwlock_write_unlock(&tree->rwlock);
-                async_answer_0(callid, rc);
-                return;
-        }
-        
-        /* Check that function with same name is not there already. */
-        if (find_fun_node_in_device(pdev, fun_name) != NULL) {
-                fibril_rwlock_write_unlock(&tree->rwlock);
-                async_answer_0(callid, EEXISTS);
-                printf(NAME ": Warning, driver tried to register `%s' twice.\n",
-                    fun_name);
-                free(fun_name);
-                return;
-        }
-
-        fun_node_t *fun = create_fun_node();
-        if (!insert_fun_node(&device_tree, fun, fun_name, pdev)) {
-                fibril_rwlock_write_unlock(&tree->rwlock);
-                delete_fun_node(fun);
-                async_answer_0(callid, ENOMEM);
-                return;
-        }
-
-        if (ftype == fun_inner) {
+static int online_function(fun_node_t *fun)
+{
+        dev_node_t *dev;
+        
+        fibril_rwlock_write_lock(&device_tree.rwlock);
+
+        if (fun->state == FUN_ON_LINE) {
+                fibril_rwlock_write_unlock(&device_tree.rwlock);
+                log_msg(LVL_WARN, "Function %s is already on line.",
+                    fun->pathname);
+                return EOK;
+        }
+        
+        if (fun->ftype == fun_inner) {
                 dev = create_dev_node();
                 if (dev == NULL) {
-                        fibril_rwlock_write_unlock(&tree->rwlock);
-                        delete_fun_node(fun);
-                        async_answer_0(callid, ENOMEM);
-                        return;
+                        fibril_rwlock_write_unlock(&device_tree.rwlock);
+                        return ENOMEM;
                 }
 
-                insert_dev_node(tree, dev, fun);
-        }
-
-        fibril_rwlock_write_unlock(&tree->rwlock);
+                insert_dev_node(&device_tree, dev, fun);
+                dev_add_ref(dev);
+        }
         
         log_msg(LVL_DEBUG, "devman_add_function(fun=\"%s\")", fun->pathname);
         
-        devman_receive_match_ids(match_count, &fun->match_ids);
-
-        if (ftype == fun_inner) {
+        if (fun->ftype == fun_inner) {
+                dev = fun->child;
                 assert(dev != NULL);
+                
+                /* Give one reference over to assign_driver_fibril(). */
+                dev_add_ref(dev);
                 /*
                  * Try to find a suitable driver and assign it to the device.  We do
@@ -317 +281 @@
                 fid_t assign_fibril = fibril_create(assign_driver_fibril, dev);
                 if (assign_fibril == 0) {
-                        /*
-                         * Fallback in case we are out of memory.
-                         * Probably not needed as we will die soon anyway ;-).
-                         */
-                        (void) assign_driver_fibril(fun);
-                } else {
-                        fibril_add_ready(assign_fibril);
+                        log_msg(LVL_ERROR, "Failed to create fibril for "
+                            "assigning driver.");
+                        /* XXX Cleanup */
+                        fibril_rwlock_write_unlock(&device_tree.rwlock);
+                        return ENOMEM;
+                }
+                fibril_add_ready(assign_fibril);
+        } else {
+                loc_register_tree_function(fun, &device_tree);
+        }
+        
+        fibril_rwlock_write_unlock(&device_tree.rwlock);
+        
+        return EOK;
+}
+
+static int offline_function(fun_node_t *fun)
+{
+        int rc;
+        
+        fibril_rwlock_write_lock(&device_tree.rwlock);
+        
+        if (fun->state == FUN_OFF_LINE) {
+                fibril_rwlock_write_unlock(&device_tree.rwlock);
+                log_msg(LVL_WARN, "Function %s is already off line.",
+                    fun->pathname);
+                return EOK;
+        }
+        
+        if (fun->ftype == fun_inner) {
+                log_msg(LVL_DEBUG, "Offlining inner function %s.",
+                    fun->pathname);
+                
+                if (fun->child != NULL) {
+                        dev_node_t *dev = fun->child;
+                        
+                        dev_add_ref(dev);
+                        fibril_rwlock_write_unlock(&device_tree.rwlock);
+                        
+                        /* If device is owned by driver, ask driver to give it up. */
+                        if (dev->state == DEVICE_USABLE) {
+                                rc = driver_dev_remove(&device_tree, dev);
+                                if (rc != EOK) {
+                                        dev_del_ref(dev);
+                                        return ENOTSUP;
+                                }
+                        }
+                        
+                        /* Verify that driver removed all functions */
+                        fibril_rwlock_read_lock(&device_tree.rwlock);
+                        if (!list_empty(&dev->functions)) {
+                                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                                return EIO;
+                        }
+                        driver_t *driver = dev->drv;
+                        fibril_rwlock_read_unlock(&device_tree.rwlock);
+                        
+                        if (driver)
+                                detach_driver(&device_tree, dev);
+                        
+                        fibril_rwlock_write_lock(&device_tree.rwlock);
+                        remove_dev_node(&device_tree, dev);
+                        
+                        /* Delete ref created when node was inserted */
+                        dev_del_ref(dev);
+                        /* Delete ref created by dev_add_ref(dev) above */
+                        dev_del_ref(dev);
                 }
         } else {
-                devmap_register_tree_function(fun, tree);
+                /* Unregister from location service */
+                rc = loc_service_unregister(fun->service_id);
+                if (rc != EOK) {
+                        fibril_rwlock_write_unlock(&device_tree.rwlock);
+                        log_msg(LVL_ERROR, "Failed unregistering tree service.");
+                        return EIO;
+                }
+                
+                fun->service_id = 0;
+        }
+        
+        fun->state = FUN_OFF_LINE;
+        fibril_rwlock_write_unlock(&device_tree.rwlock);
+        
+        return EOK;
+}
+
+/** Handle function registration.
+ *
+ * Child devices are registered by their parent's device driver.
+ */
+static void devman_add_function(ipc_callid_t callid, ipc_call_t *call)
+{
+        fun_type_t ftype = (fun_type_t) IPC_GET_ARG1(*call);
+        devman_handle_t dev_handle = IPC_GET_ARG2(*call);
+        sysarg_t match_count = IPC_GET_ARG3(*call);
+        dev_tree_t *tree = &device_tree;
+        
+        dev_node_t *pdev = find_dev_node(&device_tree, dev_handle);
+        if (pdev == NULL) {
+                async_answer_0(callid, ENOENT);
+                return;
+        }
+        
+        if (ftype != fun_inner && ftype != fun_exposed) {
+                /* Unknown function type */
+                log_msg(LVL_ERROR, 
+                    "Unknown function type %d provided by driver.",
+                    (int) ftype);
+
+                dev_del_ref(pdev);
+                async_answer_0(callid, EINVAL);
+                return;
+        }
+        
+        char *fun_name = NULL;
+        int rc = async_data_write_accept((void **)&fun_name, true, 0, 0, 0, 0);
+        if (rc != EOK) {
+                dev_del_ref(pdev);
+                async_answer_0(callid, rc);
+                return;
+        }
+        
+        fibril_rwlock_write_lock(&tree->rwlock);
+        
+        /* Check device state */
+        if (pdev->state == DEVICE_REMOVED) {
+                fibril_rwlock_write_unlock(&tree->rwlock);
+                dev_del_ref(pdev);
+                async_answer_0(callid, ENOENT);
+                return;
+        }
+        
+        /* Check that function with same name is not there already. */
+        if (find_fun_node_in_device(tree, pdev, fun_name) != NULL) {
+                fibril_rwlock_write_unlock(&tree->rwlock);
+                dev_del_ref(pdev);
+                async_answer_0(callid, EEXISTS);
+                printf(NAME ": Warning, driver tried to register `%s' twice.\n",
+                    fun_name);
+                free(fun_name);
+                return;
+        }
+        
+        fun_node_t *fun = create_fun_node();
+        fun_add_ref(fun);
+        fun->ftype = ftype;
+        
+        if (!insert_fun_node(&device_tree, fun, fun_name, pdev)) {
+                fibril_rwlock_write_unlock(&tree->rwlock);
+                dev_del_ref(pdev);
+                delete_fun_node(fun);
+                async_answer_0(callid, ENOMEM);
+                return;
+        }
+        
+        fibril_rwlock_write_unlock(&tree->rwlock);
+        dev_del_ref(pdev);
+        
+        devman_receive_match_ids(match_count, &fun->match_ids);
+        
+        rc = online_function(fun);
+        if (rc != EOK) {
+                /* XXX clean up */
+                async_answer_0(callid, rc);
+                return;
         }
         
@@ -333 +452 @@
 }
 
-static void devmap_register_class_dev(dev_class_info_t *cli)
-{
-        /* Create devmap path and name for the device. */
-        char *devmap_pathname = NULL;
-
-        asprintf(&devmap_pathname, "%s/%s%c%s", DEVMAP_CLASS_NAMESPACE,
-            cli->dev_class->name, DEVMAP_SEPARATOR, cli->dev_name);
-        if (devmap_pathname == NULL)
-                return;
-        
-        /*
-         * Register the device by the device mapper and remember its devmap
-         * handle.
-         */
-        devmap_device_register_with_iface(devmap_pathname,
-            &cli->devmap_handle, DEVMAN_CONNECT_FROM_DEVMAP);
-        
-        /*
-         * Add device to the hash map of class devices registered by device
-         * mapper.
-         */
-        class_add_devmap_function(&class_list, cli);
-        
-        free(devmap_pathname);
-}
-
-static void devman_add_function_to_class(ipc_callid_t callid, ipc_call_t *call)
+static void devman_add_function_to_cat(ipc_callid_t callid, ipc_call_t *call)
 {
         devman_handle_t handle = IPC_GET_ARG1(*call);
-        
-        /* Get class name. */
-        char *class_name;
-        int rc = async_data_write_accept((void **) &class_name, true,
+        category_id_t cat_id;
+        int rc;
+        
+        /* Get category name. */
+        char *cat_name;
+        rc = async_data_write_accept((void **) &cat_name, true,
             0, 0, 0, 0);
         if (rc != EOK) {
                 async_answer_0(callid, rc);
                 return;
-        }       
+        }
         
         fun_node_t *fun = find_fun_node(&device_tree, handle);
@@ -378 +473 @@
         }
         
-        dev_class_t *cl = get_dev_class(&class_list, class_name);
-        dev_class_info_t *class_info = add_function_to_class(fun, cl, NULL);
-        
-        /* Register the device's class alias by devmapper. */
-        devmap_register_class_dev(class_info);
-        
-        log_msg(LVL_NOTE, "Function `%s' added to class `%s' as `%s'.",
-            fun->pathname, class_name, class_info->dev_name);
-
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+        
+        /* Check function state */
+        if (fun->state == FUN_REMOVED) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(callid, ENOENT);
+                return;
+        }
+        
+        rc = loc_category_get_id(cat_name, &cat_id, IPC_FLAG_BLOCKING);
+        if (rc == EOK) {
+                loc_service_add_to_cat(fun->service_id, cat_id);
+        } else {
+                log_msg(LVL_ERROR, "Failed adding function `%s' to category "
+                    "`%s'.", fun->pathname, cat_name);
+        }
+        
+        log_msg(LVL_NOTE, "Function `%s' added to category `%s'.",
+            fun->pathname, cat_name);
+
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        fun_del_ref(fun);
+
+        async_answer_0(callid, EOK);
+}
+
+/** Online function by driver request.
+ *
+ */
+static void devman_drv_fun_online(ipc_callid_t iid, ipc_call_t *icall,
+    driver_t *drv)
+{
+        fun_node_t *fun;
+        int rc;
+
+        printf("devman_drv_fun_online()\n");
+        fun = find_fun_node(&device_tree, IPC_GET_ARG1(*icall));
+        if (fun == NULL) {
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+        if (fun->dev == NULL || fun->dev->drv != drv) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                fun_del_ref(fun);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        
+        rc = online_function(fun);
+        if (rc != EOK) {
+                printf("devman_drv_fun_online() online_fun->ERROR\n");
+                fun_del_ref(fun);
+                async_answer_0(iid, (sysarg_t) rc);
+                return;
+        }
+        
+        fun_del_ref(fun);
+        printf("devman_drv_fun_online() online_fun->OK\n");
+        
+        async_answer_0(iid, (sysarg_t) EOK);
+}
+
+
+/** Offline function by driver request.
+ *
+ */
+static void devman_drv_fun_offline(ipc_callid_t iid, ipc_call_t *icall,
+    driver_t *drv)
+{
+        fun_node_t *fun;
+        int rc;
+
+        fun = find_fun_node(&device_tree, IPC_GET_ARG1(*icall));
+        if (fun == NULL) {
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        fibril_rwlock_write_lock(&device_tree.rwlock);
+        if (fun->dev == NULL || fun->dev->drv != drv) {
+                fun_del_ref(fun);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        fibril_rwlock_write_unlock(&device_tree.rwlock);
+        
+        rc = offline_function(fun);
+        if (rc != EOK) {
+                fun_del_ref(fun);
+                async_answer_0(iid, (sysarg_t) rc);
+                return;
+        }
+        
+        fun_del_ref(fun);
+        async_answer_0(iid, (sysarg_t) EOK);
+}
+
+/** Remove function. */
+static void devman_remove_function(ipc_callid_t callid, ipc_call_t *call)
+{
+        devman_handle_t fun_handle = IPC_GET_ARG1(*call);
+        dev_tree_t *tree = &device_tree;
+        int rc;
+        
+        
+        fun_node_t *fun = find_fun_node(&device_tree, fun_handle);
+        if (fun == NULL) {
+                async_answer_0(callid, ENOENT);
+                return;
+        }
+        
+        fibril_rwlock_write_lock(&tree->rwlock);
+        
+        log_msg(LVL_DEBUG, "devman_remove_function(fun='%s')", fun->pathname);
+        
+        /* Check function state */
+        if (fun->state == FUN_REMOVED) {
+                fibril_rwlock_write_unlock(&tree->rwlock);
+                async_answer_0(callid, ENOENT);
+                return;
+        }
+        
+        if (fun->ftype == fun_inner) {
+                /* Handle possible descendants */
+                /* TODO - This is a surprise removal */
+                if (fun->child != NULL) {
+                        log_msg(LVL_WARN, "devman_remove_function(): not handling "
+                            "descendants\n");
+                }
+        } else {
+                if (fun->service_id != 0) {
+                        /* Unregister from location service */
+                        rc = loc_service_unregister(fun->service_id);
+                        if (rc != EOK) {
+                                log_msg(LVL_ERROR, "Failed unregistering tree "
+                                    "service.");
+                                fibril_rwlock_write_unlock(&tree->rwlock);
+                                fun_del_ref(fun);
+                                async_answer_0(callid, EIO);
+                                return;
+                        }
+                }
+        }
+        
+        remove_fun_node(&device_tree, fun);
+        fibril_rwlock_write_unlock(&tree->rwlock);
+        
+        /* Delete ref added when inserting function into tree */
+        fun_del_ref(fun);
+        /* Delete ref added above when looking up function */
+        fun_del_ref(fun);
+        
+        log_msg(LVL_DEBUG, "devman_remove_function() succeeded.");
         async_answer_0(callid, EOK);
 }
@@ -408 +650 @@
 static void devman_connection_driver(ipc_callid_t iid, ipc_call_t *icall)
 {
+        client_t *client;
+        driver_t *driver;
+        
         /* Accept the connection. */
         async_answer_0(iid, EOK);
         
-        driver_t *driver = devman_driver_register();
-        if (driver == NULL)
-                return;
-        
-        /*
-         * Initialize the driver as running (e.g. pass assigned devices to it)
-         * in a separate fibril; the separate fibril is used to enable the
-         * driver to use devman service during the driver's initialization.
-         */
-        fid_t fid = fibril_create(init_running_drv, driver);
-        if (fid == 0) {
-                log_msg(LVL_ERROR, "Failed to create initialization fibril " \
-                    "for driver `%s'.", driver->name);
-                return;
-        }
-        fibril_add_ready(fid);
+        client = async_get_client_data();
+        if (client == NULL) {
+                log_msg(LVL_ERROR, "Failed to allocate client data.");
+                return;
+        }
         
         while (true) {
@@ -435 +669 @@
                         break;
                 
+                if (IPC_GET_IMETHOD(call) != DEVMAN_DRIVER_REGISTER) {
+                        fibril_mutex_lock(&client->mutex);
+                        driver = client->driver;
+                        fibril_mutex_unlock(&client->mutex);
+                        if (driver == NULL) {
+                                /* First call must be to DEVMAN_DRIVER_REGISTER */
+                                async_answer_0(callid, ENOTSUP);
+                                continue;
+                        }
+                }
+                
                 switch (IPC_GET_IMETHOD(call)) {
+                case DEVMAN_DRIVER_REGISTER:
+                        fibril_mutex_lock(&client->mutex);
+                        if (client->driver != NULL) {
+                                fibril_mutex_unlock(&client->mutex);
+                                async_answer_0(callid, EINVAL);
+                                continue;
+                        }
+                        client->driver = devman_driver_register(callid, &call);
+                        fibril_mutex_unlock(&client->mutex);
+                        break;
                 case DEVMAN_ADD_FUNCTION:
                         devman_add_function(callid, &call);
                         break;
-                case DEVMAN_ADD_DEVICE_TO_CLASS:
-                        devman_add_function_to_class(callid, &call);
+                case DEVMAN_ADD_DEVICE_TO_CATEGORY:
+                        devman_add_function_to_cat(callid, &call);
+                        break;
+                case DEVMAN_DRV_FUN_ONLINE:
+                        devman_drv_fun_online(callid, &call, driver);
+                        break;
+                case DEVMAN_DRV_FUN_OFFLINE:
+                        devman_drv_fun_offline(callid, &call, driver);
+                        break;
+                case DEVMAN_REMOVE_FUNCTION:
+                        devman_remove_function(callid, &call);
                         break;
                 default:
-                        async_answer_0(callid, EINVAL); 
+                        async_answer_0(callid, EINVAL);
                         break;
                 }
@@ -454 +718 @@
 {
         char *pathname;
+        devman_handle_t handle;
         
         int rc = async_data_write_accept((void **) &pathname, true, 0, 0, 0, 0);
@@ -470 +735 @@
         }
 
-        async_answer_1(iid, EOK, fun->handle);
-}
-
-/** Find handle for the device instance identified by device class name. */
-static void devman_function_get_handle_by_class(ipc_callid_t iid,
-    ipc_call_t *icall)
-{
-        char *classname;
-        char *devname;
-
-        int rc = async_data_write_accept((void **) &classname, true, 0, 0, 0, 0);
-        if (rc != EOK) {
-                async_answer_0(iid, rc);
-                return;
-        }
-        rc = async_data_write_accept((void **) &devname, true, 0, 0, 0, 0);
-        if (rc != EOK) {
-                free(classname);
-                async_answer_0(iid, rc);
-                return;
-        }
-
-
-        fun_node_t *fun = find_fun_node_by_class(&class_list,
-            classname, devname);
-
-        free(classname);
-        free(devname);
-
-        if (fun == NULL) {
-                async_answer_0(iid, ENOENT);
-                return;
-        }
-
-        async_answer_1(iid, EOK, fun->handle);
-}
-
-/** Find device path by its handle. */
-static void devman_get_device_path_by_handle(ipc_callid_t iid,
-    ipc_call_t *icall)
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+
+        /* Check function state */
+        if (fun->state == FUN_REMOVED) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        handle = fun->handle;
+
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+
+        /* Delete reference created above by find_fun_node_by_path() */
+        fun_del_ref(fun);
+
+        async_answer_1(iid, EOK, handle);
+}
+
+/** Get device name. */
+static void devman_fun_get_name(ipc_callid_t iid, ipc_call_t *icall)
 {
         devman_handle_t handle = IPC_GET_ARG1(*icall);
@@ -523 +768 @@
         if (!async_data_read_receive(&data_callid, &data_len)) {
                 async_answer_0(iid, EINVAL);
+                fun_del_ref(fun);
                 return;
         }
@@ -530 +776 @@
                 async_answer_0(data_callid, ENOMEM);
                 async_answer_0(iid, ENOMEM);
-                return;
-        }
-
+                fun_del_ref(fun);
+                return;
+        }
+
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+
+        /* Check function state */
+        if (fun->state == FUN_REMOVED) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                free(buffer);
+
+                async_answer_0(data_callid, ENOENT);
+                async_answer_0(iid, ENOENT);
+                fun_del_ref(fun);
+                return;
+        }
+
+        size_t sent_length = str_size(fun->name);
+        if (sent_length > data_len) {
+                sent_length = data_len;
+        }
+
+        async_data_read_finalize(data_callid, fun->name, sent_length);
+        async_answer_0(iid, EOK);
+
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        fun_del_ref(fun);
+        free(buffer);
+}
+
+
+/** Get device path. */
+static void devman_fun_get_path(ipc_callid_t iid, ipc_call_t *icall)
+{
+        devman_handle_t handle = IPC_GET_ARG1(*icall);
+
+        fun_node_t *fun = find_fun_node(&device_tree, handle);
+        if (fun == NULL) {
+                async_answer_0(iid, ENOMEM);
+                return;
+        }
+
+        ipc_callid_t data_callid;
+        size_t data_len;
+        if (!async_data_read_receive(&data_callid, &data_len)) {
+                async_answer_0(iid, EINVAL);
+                fun_del_ref(fun);
+                return;
+        }
+
+        void *buffer = malloc(data_len);
+        if (buffer == NULL) {
+                async_answer_0(data_callid, ENOMEM);
+                async_answer_0(iid, ENOMEM);
+                fun_del_ref(fun);
+                return;
+        }
+        
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+        
+        /* Check function state */
+        if (fun->state == FUN_REMOVED) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                free(buffer);
+
+                async_answer_0(data_callid, ENOENT);
+                async_answer_0(iid, ENOENT);
+                fun_del_ref(fun);
+                return;
+        }
+        
         size_t sent_length = str_size(fun->pathname);
         if (sent_length > data_len) {
@@ -541 +855 @@
         async_answer_0(iid, EOK);
 
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        fun_del_ref(fun);
         free(buffer);
 }
 
+static void devman_dev_get_functions(ipc_callid_t iid, ipc_call_t *icall)
+{
+        ipc_callid_t callid;
+        size_t size;
+        size_t act_size;
+        int rc;
+        
+        if (!async_data_read_receive(&callid, &size)) {
+                async_answer_0(callid, EREFUSED);
+                async_answer_0(iid, EREFUSED);
+                return;
+        }
+        
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+        
+        dev_node_t *dev = find_dev_node_no_lock(&device_tree,
+            IPC_GET_ARG1(*icall));
+        if (dev == NULL || dev->state == DEVICE_REMOVED) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(callid, ENOENT);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        devman_handle_t *hdl_buf = (devman_handle_t *) malloc(size);
+        if (hdl_buf == NULL) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(callid, ENOMEM);
+                async_answer_0(iid, ENOMEM);
+                return;
+        }
+        
+        rc = dev_get_functions(&device_tree, dev, hdl_buf, size, &act_size);
+        if (rc != EOK) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(callid, rc);
+                async_answer_0(iid, rc);
+                return;
+        }
+        
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        
+        sysarg_t retval = async_data_read_finalize(callid, hdl_buf, size);
+        free(hdl_buf);
+        
+        async_answer_1(iid, retval, act_size);
+}
+
+
+/** Get handle for child device of a function. */
+static void devman_fun_get_child(ipc_callid_t iid, ipc_call_t *icall)
+{
+        fun_node_t *fun;
+        
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+        
+        fun = find_fun_node_no_lock(&device_tree, IPC_GET_ARG1(*icall));
+        if (fun == NULL || fun->state == FUN_REMOVED) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        if (fun->child == NULL) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        async_answer_1(iid, EOK, fun->child->handle);
+        
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+}
+
+/** Online function.
+ *
+ * Send a request to online a function to the responsible driver.
+ * The driver may offline other functions if necessary (i.e. if the state
+ * of this function is linked to state of another function somehow).
+ */
+static void devman_fun_online(ipc_callid_t iid, ipc_call_t *icall)
+{
+        fun_node_t *fun;
+        int rc;
+
+        fun = find_fun_node(&device_tree, IPC_GET_ARG1(*icall));
+        if (fun == NULL) {
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        rc = driver_fun_online(&device_tree, fun);
+        fun_del_ref(fun);
+        
+        async_answer_0(iid, (sysarg_t) rc);
+}
+
+/** Offline function.
+ *
+ * Send a request to offline a function to the responsible driver. As
+ * a result the subtree rooted at that function should be cleanly
+ * detatched. The driver may offline other functions if necessary
+ * (i.e. if the state of this function is linked to state of another
+ * function somehow).
+ */
+static void devman_fun_offline(ipc_callid_t iid, ipc_call_t *icall)
+{
+        fun_node_t *fun;
+        int rc;
+
+        fun = find_fun_node(&device_tree, IPC_GET_ARG1(*icall));
+        if (fun == NULL) {
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        rc = driver_fun_offline(&device_tree, fun);
+        fun_del_ref(fun);
+        
+        async_answer_0(iid, (sysarg_t) rc);
+}
+
+/** Find handle for the function instance identified by its service ID. */
+static void devman_fun_sid_to_handle(ipc_callid_t iid, ipc_call_t *icall)
+{
+        fun_node_t *fun;
+
+        fun = find_loc_tree_function(&device_tree, IPC_GET_ARG1(*icall));
+        
+        if (fun == NULL) {
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+
+        /* Check function state */
+        if (fun->state == FUN_REMOVED) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+
+        async_answer_1(iid, EOK, fun->handle);
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        fun_del_ref(fun);
+}
 
 /** Function for handling connections from a client to the device manager. */
@@ -562 +1025 @@
                         devman_function_get_handle(callid, &call);
                         break;
-                case DEVMAN_DEVICE_GET_HANDLE_BY_CLASS:
-                        devman_function_get_handle_by_class(callid, &call);
-                        break;
-                case DEVMAN_DEVICE_GET_DEVICE_PATH:
-                        devman_get_device_path_by_handle(callid, &call);
+                case DEVMAN_DEV_GET_FUNCTIONS:
+                        devman_dev_get_functions(callid, &call);
+                        break;
+                case DEVMAN_FUN_GET_CHILD:
+                        devman_fun_get_child(callid, &call);
+                        break;
+                case DEVMAN_FUN_GET_NAME:
+                        devman_fun_get_name(callid, &call);
+                        break;
+                case DEVMAN_FUN_GET_PATH:
+                        devman_fun_get_path(callid, &call);
+                        break;
+                case DEVMAN_FUN_ONLINE:
+                        devman_fun_online(callid, &call);
+                        break;
+                case DEVMAN_FUN_OFFLINE:
+                        devman_fun_offline(callid, &call);
+                        break;
+                case DEVMAN_FUN_SID_TO_HANDLE:
+                        devman_fun_sid_to_handle(callid, &call);
                         break;
                 default:
@@ -585 +1063 @@
         if (fun == NULL)
                 dev = find_dev_node(&device_tree, handle);
-        else
+        else {
+                fibril_rwlock_read_lock(&device_tree.rwlock);
                 dev = fun->dev;
+                if (dev != NULL)
+                        dev_add_ref(dev);
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+        }
 
         /*
@@ -598 +1081 @@
                     "function with handle %" PRIun " was found.", handle);
                 async_answer_0(iid, ENOENT);
-                return;
+                goto cleanup;
         }
 
@@ -606 +1089 @@
                     handle);
                 async_answer_0(iid, ENOENT);
-                return;
+                goto cleanup;
         }
         
         driver_t *driver = NULL;
+        
+        fibril_rwlock_read_lock(&device_tree.rwlock);
         
         if (drv_to_parent) {
@@ -624 +1109 @@
         }
         
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        
         if (driver == NULL) {
                 log_msg(LVL_ERROR, "IPC forwarding refused - " \
                     "the device %" PRIun " is not in usable state.", handle);
                 async_answer_0(iid, ENOENT);
-                return;
+                goto cleanup;
         }
         
@@ -641 +1128 @@
                     "Could not forward to driver `%s'.", driver->name);
                 async_answer_0(iid, EINVAL);
-                return;
+                goto cleanup;
         }
 
@@ -657 +1144 @@
         async_forward_fast(iid, exch, method, fwd_h, 0, IPC_FF_NONE);
         async_exchange_end(exch);
-}
-
-/** Function for handling connections from a client forwarded by the device
- * mapper to the device manager. */
-static void devman_connection_devmapper(ipc_callid_t iid, ipc_call_t *icall)
-{
-        devmap_handle_t devmap_handle = IPC_GET_ARG2(*icall);
+
+cleanup:
+        if (dev != NULL)
+                dev_del_ref(dev);
+        if (fun != NULL)
+                fun_del_ref(fun);
+}
+
+/** Function for handling connections from a client forwarded by the location
+ * service to the device manager. */
+static void devman_connection_loc(ipc_callid_t iid, ipc_call_t *icall)
+{
+        service_id_t service_id = IPC_GET_ARG2(*icall);
         fun_node_t *fun;
         dev_node_t *dev;
-
-        fun = find_devmap_tree_function(&device_tree, devmap_handle);
-        if (fun == NULL)
-                fun = find_devmap_class_function(&class_list, devmap_handle);
-        
-        if (fun == NULL || fun->dev->drv == NULL) {
+        devman_handle_t handle;
+        driver_t *driver;
+
+        fun = find_loc_tree_function(&device_tree, service_id);
+        
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+        
+        if (fun == NULL || fun->dev == NULL || fun->dev->drv == NULL) {
+                log_msg(LVL_WARN, "devman_connection_loc(): function "
+                    "not found.\n");
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
                 async_answer_0(iid, ENOENT);
                 return;
@@ -677 +1175 @@
         
         dev = fun->dev;
-        
-        if ((dev->state != DEVICE_USABLE) || (!dev->drv->sess)) {
-                async_answer_0(iid, EINVAL);
-                return;
-        }
-        
-        async_exch_t *exch = async_exchange_begin(dev->drv->sess);
-        async_forward_fast(iid, exch, DRIVER_CLIENT, fun->handle, 0,
+        driver = dev->drv;
+        handle = fun->handle;
+        
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        
+        async_exch_t *exch = async_exchange_begin(driver->sess);
+        async_forward_fast(iid, exch, DRIVER_CLIENT, handle, 0,
             IPC_FF_NONE);
         async_exchange_end(exch);
         
         log_msg(LVL_DEBUG,
-            "Forwarding devmapper request for `%s' function to driver `%s'.",
-            fun->pathname, dev->drv->name);
+            "Forwarding loc service request for `%s' function to driver `%s'.",
+            fun->pathname, driver->name);
+
+        fun_del_ref(fun);
 }
 
 /** Function for handling connections to device manager. */
-static void devman_connection(ipc_callid_t iid, ipc_call_t *icall)
-{
-        /* Select interface. */
+static void devman_connection(ipc_callid_t iid, ipc_call_t *icall, void *arg)
+{
+        /* Select port. */
         switch ((sysarg_t) (IPC_GET_ARG1(*icall))) {
         case DEVMAN_DRIVER:
@@ -708 +1207 @@
                 devman_forward(iid, icall, false);
                 break;
-        case DEVMAN_CONNECT_FROM_DEVMAP:
-                /* Someone connected through devmap node. */
-                devman_connection_devmapper(iid, icall);
+        case DEVMAN_CONNECT_FROM_LOC:
+                /* Someone connected through loc node. */
+                devman_connection_loc(iid, icall);
                 break;
         case DEVMAN_CONNECT_TO_PARENTS_DEVICE:
@@ -722 +1221 @@
 }
 
+static void *devman_client_data_create(void)
+{
+        client_t *client;
+        
+        client = calloc(1, sizeof(client_t));
+        if (client == NULL)
+                return NULL;
+        
+        fibril_mutex_initialize(&client->mutex);
+        return client;
+}
+
+static void devman_client_data_destroy(void *data)
+{
+        free(data);
+}
+
 /** Initialize device manager internal structures. */
 static bool devman_init(void)
@@ -743 +1259 @@
         }
 
-        init_class_list(&class_list);
-        
         /*
-         * !!! devman_connection ... as the device manager is not a real devmap
+         * !!! devman_connection ... as the device manager is not a real loc
          * driver (it uses a completely different ipc protocol than an ordinary
-         * devmap driver) forwarding a connection from client to the devman by
-         * devmapper would not work.
+         * loc driver) forwarding a connection from client to the devman by
+         * location service would not work.
          */
-        devmap_driver_register(NAME, devman_connection);
+        loc_server_register(NAME, devman_connection);
         
         return true;
@@ -760 +1274 @@
         printf(NAME ": HelenOS Device Manager\n");
 
-        if (log_init(NAME, LVL_ERROR) != EOK) {
+        if (log_init(NAME, LVL_WARN) != EOK) {
                 printf(NAME ": Error initializing logging subsystem.\n");
                 return -1;
@@ -770 +1284 @@
         }
         
-        /* Set a handler of incomming connections. */
+        /* Set handlers for incoming connections. */
+        async_set_client_data_constructor(devman_client_data_create);
+        async_set_client_data_destructor(devman_client_data_destroy);
         async_set_client_connection(devman_connection);