Changes in uspace/srv/devman/main.c [181c32f:c4f7bf6] in mainline

File:

• uspace/srv/devman/main.c (modified) (2 diffs)

uspace/srv/devman/main.c

@@ -36 +36 @@
  */
 
+#include <inttypes.h>
 #include <assert.h>
 #include <ipc/services.h>
@@ -42 +43 @@
 #include <stdio.h>
 #include <errno.h>
+#include <str_error.h>
 #include <stdbool.h>
 #include <fibril_synch.h>
 #include <stdlib.h>
 #include <str.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <sys/stat.h>
 #include <ctype.h>
 #include <io/log.h>
 #include <ipc/devman.h>
 #include <ipc/driver.h>
+#include <thread.h>
 #include <loc.h>
 
-#include "client_conn.h"
-#include "dev.h"
 #include "devman.h"
-#include "devtree.h"
-#include "drv_conn.h"
-#include "driver.h"
-#include "fun.h"
-#include "loc.h"
 
 #define DRIVER_DEFAULT_STORE  "/drv"
 
-driver_list_t drivers_list;
-dev_tree_t device_tree;
+static driver_list_t drivers_list;
+static dev_tree_t device_tree;
+
+static int init_running_drv(void *drv);
+
+/** Register running driver. */
+static driver_t *devman_driver_register(ipc_callid_t callid, ipc_call_t *call)
+{
+        driver_t *driver = NULL;
+        char *drv_name = NULL;
+
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "devman_driver_register");
+        
+        /* Get driver name. */
+        int rc = async_data_write_accept((void **) &drv_name, true, 0, 0, 0, 0);
+        if (rc != EOK) {
+                async_answer_0(callid, rc);
+                return NULL;
+        }
+
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "The `%s' driver is trying to register.",
+            drv_name);
+        
+        /* Find driver structure. */
+        driver = find_driver(&drivers_list, drv_name);
+        if (driver == NULL) {
+                log_msg(LOG_DEFAULT, LVL_ERROR, "No driver named `%s' was found.", drv_name);
+                free(drv_name);
+                drv_name = NULL;
+                async_answer_0(callid, ENOENT);
+                return NULL;
+        }
+        
+        free(drv_name);
+        drv_name = NULL;
+        
+        fibril_mutex_lock(&driver->driver_mutex);
+        
+        if (driver->sess) {
+                /* We already have a connection to the driver. */
+                log_msg(LOG_DEFAULT, LVL_ERROR, "Driver '%s' already started.\n",
+                    driver->name);
+                fibril_mutex_unlock(&driver->driver_mutex);
+                async_answer_0(callid, EEXISTS);
+                return NULL;
+        }
+        
+        switch (driver->state) {
+        case DRIVER_NOT_STARTED:
+                /* Somebody started the driver manually. */
+                log_msg(LOG_DEFAULT, LVL_NOTE, "Driver '%s' started manually.\n",
+                    driver->name);
+                driver->state = DRIVER_STARTING;
+                break;
+        case DRIVER_STARTING:
+                /* The expected case */
+                break;
+        case DRIVER_RUNNING:
+                /* Should not happen since we do not have a connected session */
+                assert(false);
+        }
+        
+        /* Create connection to the driver. */
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "Creating connection to the `%s' driver.",
+            driver->name);
+        driver->sess = async_callback_receive(EXCHANGE_PARALLEL);
+        if (!driver->sess) {
+                fibril_mutex_unlock(&driver->driver_mutex);
+                async_answer_0(callid, ENOTSUP);
+                return NULL;
+        }
+        /* FIXME: Work around problem with callback sessions */
+        async_sess_args_set(driver->sess, DRIVER_DEVMAN, 0, 0);
+        
+        log_msg(LOG_DEFAULT, LVL_NOTE,
+            "The `%s' driver was successfully registered as running.",
+            driver->name);
+        
+        /*
+         * 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(LOG_DEFAULT, 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;
+}
+
+/** Receive device match ID from the device's parent driver and add it to the
+ * list of devices match ids.
+ *
+ * @param match_ids     The list of the device's match ids.
+ * @return              Zero on success, negative error code otherwise.
+ */
+static int devman_receive_match_id(match_id_list_t *match_ids)
+{
+        match_id_t *match_id = create_match_id();
+        ipc_callid_t callid;
+        ipc_call_t call;
+        int rc = 0;
+        
+        callid = async_get_call(&call);
+        if (DEVMAN_ADD_MATCH_ID != IPC_GET_IMETHOD(call)) {
+                log_msg(LOG_DEFAULT, LVL_ERROR, 
+                    "Invalid protocol when trying to receive match id.");
+                async_answer_0(callid, EINVAL); 
+                delete_match_id(match_id);
+                return EINVAL;
+        }
+        
+        if (match_id == NULL) {
+                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed to allocate match id.");
+                async_answer_0(callid, ENOMEM);
+                return ENOMEM;
+        }
+        
+        async_answer_0(callid, EOK);
+        
+        match_id->score = IPC_GET_ARG1(call);
+        
+        char *match_id_str;
+        rc = async_data_write_accept((void **) &match_id_str, true, 0, 0, 0, 0);
+        match_id->id = match_id_str;
+        if (rc != EOK) {
+                delete_match_id(match_id);
+                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed to receive match id string: %s.",
+                    str_error(rc));
+                return rc;
+        }
+        
+        list_append(&match_id->link, &match_ids->ids);
+        
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "Received match id `%s', score %d.",
+            match_id->id, match_id->score);
+        return rc;
+}
+
+/** Receive device match IDs from the device's parent driver and add them to the
+ * list of devices match ids.
+ *
+ * @param match_count   The number of device's match ids to be received.
+ * @param match_ids     The list of the device's match ids.
+ * @return              Zero on success, negative error code otherwise.
+ */
+static int devman_receive_match_ids(sysarg_t match_count,
+    match_id_list_t *match_ids)
+{
+        int ret = EOK;
+        size_t i;
+        
+        for (i = 0; i < match_count; i++) {
+                if (EOK != (ret = devman_receive_match_id(match_ids)))
+                        return ret;
+        }
+        return ret;
+}
+
+static int assign_driver_fibril(void *arg)
+{
+        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;
+}
+
+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(LOG_DEFAULT, 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(&device_tree.rwlock);
+                        return ENOMEM;
+                }
+                
+                insert_dev_node(&device_tree, dev, fun);
+                dev_add_ref(dev);
+        }
+        
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "devman_add_function(fun=\"%s\")", fun->pathname);
+        
+        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
+                 * not want to block the current fibril that is used for processing
+                 * incoming calls: we will launch a separate fibril to handle the
+                 * driver assigning. That is because assign_driver can actually include
+                 * task spawning which could take some time.
+                 */
+                fid_t assign_fibril = fibril_create(assign_driver_fibril, dev);
+                if (assign_fibril == 0) {
+                        log_msg(LOG_DEFAULT, 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(LOG_DEFAULT, LVL_WARN, "Function %s is already off line.",
+                    fun->pathname);
+                return EOK;
+        }
+        
+        if (fun->ftype == fun_inner) {
+                log_msg(LOG_DEFAULT, LVL_DEBUG, "Offlining inner function %s.",
+                    fun->pathname);
+                
+                if (fun->child != NULL) {
+                        dev_node_t *dev = fun->child;
+                        device_state_t dev_state;
+                        
+                        dev_add_ref(dev);
+                        dev_state = dev->state;
+                        
+                        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);
+                                dev_del_ref(dev);
+                                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 {
+                /* Unregister from location service */
+                rc = loc_service_unregister(fun->service_id);
+                if (rc != EOK) {
+                        fibril_rwlock_write_unlock(&device_tree.rwlock);
+                        log_msg(LOG_DEFAULT, 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(LOG_DEFAULT, 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. */
+        fun_node_t *tfun = find_fun_node_in_device(tree, pdev, fun_name);
+        if (tfun) {
+                fun_del_ref(tfun);      /* drop the new unwanted reference */
+                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();
+        /* One reference for creation, one for us */
+        fun_add_ref(fun);
+        fun_add_ref(fun);
+        fun->ftype = ftype;
+        
+        /*
+         * We can lock the function here even when holding the tree because
+         * we know it cannot be held by anyone else yet.
+         */
+        fun_busy_lock(fun);
+        
+        if (!insert_fun_node(&device_tree, fun, fun_name, pdev)) {
+                fibril_rwlock_write_unlock(&tree->rwlock);
+                dev_del_ref(pdev);
+                fun_busy_unlock(fun);
+                fun_del_ref(fun);
+                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 Set some failed state? */
+                fun_busy_unlock(fun);
+                fun_del_ref(fun);
+                async_answer_0(callid, rc);
+                return;
+        }
+        
+        fun_busy_unlock(fun);
+        fun_del_ref(fun);
+        
+        /* Return device handle to parent's driver. */
+        async_answer_1(callid, EOK, fun->handle);
+}
+
+static void devman_add_function_to_cat(ipc_callid_t callid, ipc_call_t *call)
+{
+        devman_handle_t handle = IPC_GET_ARG1(*call);
+        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);
+        if (fun == NULL) {
+                async_answer_0(callid, 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(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);
+                log_msg(LOG_DEFAULT, LVL_NOTE, "Function `%s' added to category `%s'.",
+                    fun->pathname, cat_name);
+        } else {
+                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed adding function `%s' to category "
+                    "`%s'.", fun->pathname, cat_name);
+        }
+        
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        fun_del_ref(fun);
+        
+        async_answer_0(callid, rc);
+}
+
+/** 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;
+        
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "devman_drv_fun_online()");
+        
+        fun = find_fun_node(&device_tree, IPC_GET_ARG1(*icall));
+        if (fun == NULL) {
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        
+        fun_busy_lock(fun);
+        
+        fibril_rwlock_read_lock(&device_tree.rwlock);
+        if (fun->dev == NULL || fun->dev->drv != drv) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                fun_busy_unlock(fun);
+                fun_del_ref(fun);
+                async_answer_0(iid, ENOENT);
+                return;
+        }
+        fibril_rwlock_read_unlock(&device_tree.rwlock);
+        
+        rc = online_function(fun);
+        if (rc != EOK) {
+                fun_busy_unlock(fun);
+                fun_del_ref(fun);
+                async_answer_0(iid, (sysarg_t) rc);
+                return;
+        }
+        
+        fun_busy_unlock(fun);
+        fun_del_ref(fun);
+        
+        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;
+        }
+        
+        fun_busy_lock(fun);
+        
+        fibril_rwlock_write_lock(&device_tree.rwlock);
+        if (fun->dev == NULL || fun->dev->drv != drv) {
+                fun_busy_unlock(fun);
+                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_busy_unlock(fun);
+                fun_del_ref(fun);
+                async_answer_0(iid, (sysarg_t) rc);
+                return;
+        }
+        
+        fun_busy_unlock(fun);
+        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;
+        }
+        
+        fun_busy_lock(fun);
+        
+        fibril_rwlock_write_lock(&tree->rwlock);
+        
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "devman_remove_function(fun='%s')", fun->pathname);
+        
+        /* Check function state */
+        if (fun->state == FUN_REMOVED) {
+                fibril_rwlock_write_unlock(&tree->rwlock);
+                fun_busy_unlock(fun);
+                fun_del_ref(fun);
+                async_answer_0(callid, ENOENT);
+                return;
+        }
+        
+        if (fun->ftype == fun_inner) {
+                /* This is a surprise removal. Handle possible descendants */
+                if (fun->child != NULL) {
+                        dev_node_t *dev = fun->child;
+                        device_state_t dev_state;
+                        int gone_rc;
+                        
+                        dev_add_ref(dev);
+                        dev_state = dev->state;
+                        
+                        fibril_rwlock_write_unlock(&device_tree.rwlock);
+                        
+                        /* If device is owned by driver, inform driver it is gone. */
+                        if (dev_state == DEVICE_USABLE)
+                                gone_rc = driver_dev_gone(&device_tree, dev);
+                        else
+                                gone_rc = EOK;
+                        
+                        fibril_rwlock_read_lock(&device_tree.rwlock);
+                        
+                        /* Verify that driver succeeded and removed all functions */
+                        if (gone_rc != EOK || !list_empty(&dev->functions)) {
+                                log_msg(LOG_DEFAULT, LVL_ERROR, "Driver did not remove "
+                                    "functions for device that is gone. "
+                                    "Device node is now defunct.");
+                                
+                                /*
+                                 * Not much we can do but mark the device
+                                 * node as having invalid state. This
+                                 * is a driver bug.
+                                 */
+                                dev->state = DEVICE_INVALID;
+                                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                                dev_del_ref(dev);
+                                if (gone_rc == EOK)
+                                        gone_rc = ENOTSUP;
+                                fun_busy_unlock(fun);
+                                fun_del_ref(fun);
+                                async_answer_0(callid, gone_rc);
+                                return;
+                        }
+                        
+                        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 {
+                if (fun->service_id != 0) {
+                        /* Unregister from location service */
+                        rc = loc_service_unregister(fun->service_id);
+                        if (rc != EOK) {
+                                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed unregistering tree "
+                                    "service.");
+                                fibril_rwlock_write_unlock(&tree->rwlock);
+                                fun_busy_unlock(fun);
+                                fun_del_ref(fun);
+                                async_answer_0(callid, EIO);
+                                return;
+                        }
+                }
+        }
+        
+        remove_fun_node(&device_tree, fun);
+        fibril_rwlock_write_unlock(&tree->rwlock);
+        fun_busy_unlock(fun);
+        
+        /* 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(LOG_DEFAULT, LVL_DEBUG, "devman_remove_function() succeeded.");
+        async_answer_0(callid, EOK);
+}
+
+/** Initialize driver which has registered itself as running and ready.
+ *
+ * The initialization is done in a separate fibril to avoid deadlocks (if the
+ * driver needed to be served by devman during the driver's initialization).
+ */
+static int init_running_drv(void *drv)
+{
+        driver_t *driver = (driver_t *) drv;
+        
+        initialize_running_driver(driver, &device_tree);
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "The `%s` driver was successfully initialized.",
+            driver->name);
+        return 0;
+}
+
+/** Function for handling connections from a driver to the device manager. */
+static void devman_connection_driver(ipc_callid_t iid, ipc_call_t *icall)
+{
+        client_t *client;
+        driver_t *driver = NULL;
+        
+        /* Accept the connection. */
+        async_answer_0(iid, EOK);
+        
+        client = async_get_client_data();
+        if (client == NULL) {
+                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed to allocate client data.");
+                return;
+        }
+        
+        while (true) {
+                ipc_call_t call;
+                ipc_callid_t callid = async_get_call(&call);
+                
+                if (!IPC_GET_IMETHOD(call))
+                        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_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);
+                        break;
+                }
+        }
+}
+
+/** Find handle for the device instance identified by the device's path in the
+ * device tree. */
+static void devman_function_get_handle(ipc_callid_t iid, ipc_call_t *icall)
+{
+        char *pathname;
+        devman_handle_t handle;
+        
+        int rc = async_data_write_accept((void **) &pathname, true, 0, 0, 0, 0);
+        if (rc != EOK) {
+                async_answer_0(iid, rc);
+                return;
+        }
+        
+        fun_node_t *fun = find_fun_node_by_path(&device_tree, pathname);
+        
+        free(pathname);
+
+        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;
+        }
+        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);
+
+        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->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 function driver name. */
+static void devman_fun_get_driver_name(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;
+        }
+
+        /* Check whether function has a driver */
+        if (fun->child == NULL || fun->child->drv == NULL) {
+                fibril_rwlock_read_unlock(&device_tree.rwlock);
+                free(buffer);
+
+                async_answer_0(data_callid, EINVAL);
+                async_answer_0(iid, EINVAL);
+                fun_del_ref(fun);
+                return;
+        }
+
+        size_t sent_length = str_size(fun->child->drv->name);
+        if (sent_length > data_len) {
+                sent_length = data_len;
+        }
+
+        async_data_read_finalize(data_callid, fun->child->drv->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) {
+                sent_length = data_len;
+        }
+
+        async_data_read_finalize(data_callid, fun->pathname, sent_length);
+        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. */
+static void devman_connection_client(ipc_callid_t iid, ipc_call_t *icall)
+{
+        /* Accept connection. */
+        async_answer_0(iid, EOK);
+        
+        while (true) {
+                ipc_call_t call;
+                ipc_callid_t callid = async_get_call(&call);
+                
+                if (!IPC_GET_IMETHOD(call))
+                        break;
+                
+                switch (IPC_GET_IMETHOD(call)) {
+                case DEVMAN_DEVICE_GET_HANDLE:
+                        devman_function_get_handle(callid, &call);
+                        break;
+                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_DRIVER_NAME:
+                        devman_fun_get_driver_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:
+                        async_answer_0(callid, ENOENT);
+                }
+        }
+}
 
 static void devman_forward(ipc_callid_t iid, ipc_call_t *icall,