Changeset 798f364 in mainline

Timestamp:

2007-11-05T20:57:56Z (17 years ago)

Author:

Josef Cejka <malyzelenyhnus@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

6537572

Parents:

320c884

Message:

New version of device mapper.
Added devmap test to tester.

Location:

uspace

Files:

• app/tester/Makefile (modified) (1 diff)
• app/tester/devmap/devmap1.c (added)
• app/tester/devmap/devmap1.def (added)
• app/tester/tester.c (modified) (1 diff)
• app/tester/tester.h (modified) (1 diff)
• srv/devmap/devmap.c (modified) (4 diffs)
• srv/devmap/devmap.h (modified) (2 diffs)
• srv/ns/ns.c (modified) (1 diff)

uspace/app/tester/Makefile

@@ -52 +52 @@
         ipc/send_sync.c \
         ipc/answer.c \
-        ipc/hangup.c
+        ipc/hangup.c \
+        devmap/devmap1.c
 
 OBJECTS := $(addsuffix .o,$(basename $(SOURCES)))

uspace/app/tester/tester.c

@@ -56 +56 @@
 #include "ipc/answer.def"
 #include "ipc/hangup.def"
+#include "devmap/devmap1.def"
         {NULL, NULL, NULL}
 };

uspace/app/tester/tester.h

@@ -68 +68 @@
 extern char * test_answer(bool quiet);
 extern char * test_hangup(bool quiet);
+extern char * test_devmap1(bool quiet);
 
 extern test_t tests[];

uspace/srv/devmap/devmap.c

@@ -42 +42 @@
 #include <errno.h>
 #include <bool.h>
-#include <libadt/list.h>
 #include <futex.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include "devmap.h"
 
-LIST_INITIALIZE(device_list);
-
-atomic_t device_list_futex = FUTEX_INITIALIZER;
+
+LIST_INITIALIZE(devices_list);
+LIST_INITIALIZE(drivers_list);
+
+/* order of locking:
+ * drivers_list_futex
+ * devices_list_futex
+ * (devmap_driver_t *)->devices_futex
+ * create_handle_futex
+ **/
+
+static atomic_t devices_list_futex = FUTEX_INITIALIZER;
+static atomic_t drivers_list_futex = FUTEX_INITIALIZER;
+static atomic_t create_handle_futex = FUTEX_INITIALIZER;
+
+
+static int devmap_create_handle(void)
+{
+        static int last_handle = 0;
+        int handle;
+
+        /* TODO: allow reusing old handles after their unregistration
+                and implement some version of LRU algorithm */
+        /* FIXME: overflow */
+        futex_down(&create_handle_futex);       
+
+        last_handle += 1;
+        handle = last_handle;
+
+        futex_up(&create_handle_futex); 
+
+        return handle;
+}
+
 
 /** Initialize device mapper. 
@@ -57 +89 @@
 static int devmap_init()
 {
-        /* */
+        /* TODO: */
 
         return EOK;
 }
 
-static int devmap_register()
-{
-        ipc_callid_t callid2;
-        size_t size;
-        char buffer[DEVMAP_NAME_MAXLEN + 1];
+/** Find device with given name.
+ *
+ */
+static devmap_device_t *devmap_device_find_name(const char *name)
+{
+        link_t *item;
+        devmap_device_t *device = NULL;
+
+        item = devices_list.next;
+
+        while (item != &devices_list) {
+
+                device = list_get_instance(item, devmap_device_t, devices);
+                if (0 == strcmp(device->name, name)) {
+                        break;
+                }
+                item = item->next;
+        }
+
+        if (item == &devices_list) {
+                printf("DevMap: no device named %s.\n", name);
+                return NULL;
+        }
+
+        device = list_get_instance(item, devmap_device_t, devices);
+        return device;
+}
+
+/** Find device with given handle.
+ * @todo: use hash table
+ */
+static devmap_device_t *devmap_device_find_handle(int handle)
+{
+        link_t *item;
+        devmap_device_t *device = NULL;
+        
+        futex_down(&devices_list_futex);
+
+        item = (&devices_list)->next;
+
+        while (item != &devices_list) {
+
+                device = list_get_instance(item, devmap_device_t, devices);
+                if (device->handle == handle) {
+                        break;
+                }
+                item = item->next;
+        }
+
+        if (item == &devices_list) {
+                futex_up(&devices_list_futex);
+                return NULL;
+        }
+
+        device = list_get_instance(item, devmap_device_t, devices);
+        
+        futex_up(&devices_list_futex);
+
+        return device;
+}
+
+/** Unregister device and free it. Its assumed that driver's device list 
+ * is already locked.
+ *
+ */
+static int devmap_device_unregister_core(devmap_device_t *device)
+{
+
+        list_remove(&(device->devices));
+        list_remove(&(device->driver_devices));
+
+        free(device->name);     
+        free(device);
+
+
+        return EOK;
+}
+
+/** Read info about new driver and add it into linked list of registered drivers.
+ */
+static void devmap_driver_register(devmap_driver_t **odriver)
+{
+        size_t name_size;
         ipc_callid_t callid;
         ipc_call_t call;
-        int retval;
-        
-        if (ipc_data_receive(&callid, &call, NULL, &size) != 0) {
-        //      retval = 
-        }
-
-        if (size > DEVMAP_NAME_MAXLEN) {
-                retval = ELIMIT;
-        } else {
-                ipc_data_deliver(callid2, &call, buffer, size);
-                buffer[DEVMAP_NAME_MAXLEN] = 0;
-        }
+        devmap_driver_t *driver;
+        ipc_callid_t iid;
+        ipc_call_t icall;
+
+        *odriver = NULL;
+        
+        iid = async_get_call(&icall);
+
+        if (IPC_GET_METHOD(icall) != DEVMAP_DRIVER_REGISTER) {
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        } 
+
+        if (NULL == (driver = (devmap_driver_t *)malloc(sizeof(devmap_driver_t)))) {
+                ipc_answer_fast(iid, ENOMEM, 0, 0);
+                return;
+        }
+
+        /* 
+         * Get driver name
+         */
+        if (!ipc_data_receive(&callid, &call, NULL, &name_size)) {
+                printf("Unexpected request: %u.\n", IPC_GET_METHOD(call));
+                free(driver);
+                ipc_answer_fast(callid, EREFUSED, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+        if (name_size > DEVMAP_NAME_MAXLEN) {
+                printf("Too logn name: %u: maximum is %u.\n", name_size, DEVMAP_NAME_MAXLEN);
+                free(driver);
+                ipc_answer_fast(callid, EINVAL, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+        /*
+         * Allocate buffer for device name.
+         */
+        if (NULL == (driver->name = (char *)malloc(name_size + 1))) {
+                printf("Cannot allocate space for driver name.\n");
+                free(driver);
+                ipc_answer_fast(callid, ENOMEM, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }       
+
+        /*
+         * Send confirmation to sender and get data into buffer.
+         */
+        if (EOK != ipc_data_deliver(callid, &call, driver->name, name_size)) {
+                printf("Cannot read driver name.\n");
+                free(driver->name);
+                free(driver);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+        driver->name[name_size] = 0;
+
+        printf("Read driver name: '%s'.\n", driver->name);
+
+        /* Initialize futex for list of devices owned by this driver */
+        futex_initialize(&(driver->devices_futex) ,1);
+
+        /* 
+         * Initialize list of asociated devices
+     */
+        list_initialize(&(driver->devices));
+
+        /* 
+         * Create connection to the driver 
+         */
+        callid = async_get_call(&call);
+
+        if (IPC_M_CONNECT_TO_ME != IPC_GET_METHOD(call)) {
+                printf("DevMap: Unexpected method: %u.\n", \
+                        IPC_GET_METHOD(call));
+                ipc_answer_fast(callid, ENOTSUP, 0, 0);
+                
+                free(driver->name);
+                free(driver);
+                ipc_answer_fast(iid, ENOTSUP, 0, 0);
+                return;
+        }
+
+        driver->phone = IPC_GET_ARG3(call);
+        
+        ipc_answer_fast(callid, EOK, 0, 0);
+        
+        list_initialize(&(driver->drivers));
+
+        futex_down(&drivers_list_futex);        
+        
+        /* TODO: check that no driver with name equals to driver->name is registered */
+
+        /* 
+         * Insert new driver into list of registered drivers
+         */
+        list_append(&(driver->drivers), &drivers_list);
+        futex_up(&drivers_list_futex);  
+        
+        ipc_answer_fast(iid, EOK, 0, 0);
+        printf("Driver registered.\n");
+
+        *odriver = driver;
+        return;
+}
+
+/** Unregister device driver, unregister all its devices and free driver structure.
+ *
+ */
+static int devmap_driver_unregister(devmap_driver_t *driver)
+{
+        devmap_device_t *device;
+
+        if (NULL == driver) {
+                printf("Error: driver == NULL.\n");
+                return EEXISTS;
+        }
+
+        printf("Unregister driver '%s'.\n", driver->name);
+        futex_down(&drivers_list_futex);        
+
+        ipc_hangup(driver->phone);
+        
+        /* remove it from list of drivers */
+        list_remove(&(driver->drivers));
+
+        /* unregister all its devices */
+        
+        futex_down(&devices_list_futex);        
+        futex_down(&(driver->devices_futex));
+
+        while (!list_empty(&(driver->devices))) {
+                device = list_get_instance(driver->devices.next, devmap_device_t, driver_devices);
+                printf("Unregister device '%s'.\n", device->name);
+                devmap_device_unregister_core(device);
+        }
+        
+        futex_up(&(driver->devices_futex));
+        futex_up(&devices_list_futex);  
+        futex_up(&drivers_list_futex);  
+
+        /* free name and driver */
+        if (NULL != driver->name) {
+                free(driver->name);
+        }
+
+        free(driver);
+
+        printf("Driver unregistered.\n");
+
         return EOK;
 }
 
-static int devmap_unregister()
-{
-        return EOK;
-}
-
-static int devmap_forward(int handle, ipc_call_t *call, ipc_callid_t callid)
-{
-        link_t *item;
-        ipcarg_t phone;
-        devmap_device_t *dev;
-
-        /* FIXME: add futex */
-        futex_down(&device_list_futex);
-
-        item = (&device_list)->next;
-
-        while (item != &device_list) {
-
-                dev = list_get_instance(item, devmap_device_t, list);
-                if (dev->handle == handle) {
-                        break;
-                }
-                item = item->next;
-        }
-
-        if (item == &device_list) {
-                return ENOENT;
-        }
-
-        dev = list_get_instance(item, devmap_device_t, list);
-        phone = dev->phone;
-
-        futex_up(&device_list_futex);
-        
-        return ipc_forward_fast(callid, phone, 0, 0);
-}
-
-static int devmap_get_handle()
-{
-        return EOK;
-}
-
-/** Function for handling connections to devmap 
- *
- */
-static void
-devmap_client_connection(ipc_callid_t iid, ipc_call_t *icall)
+
+/** Register instance of device
+ *
+ */
+static void devmap_device_register(ipc_callid_t iid, ipc_call_t *icall,
+                devmap_driver_t *driver)
 {
         ipc_callid_t callid;
         ipc_call_t call;
-        int retval;
+        size_t size;
+        devmap_device_t *device;
+
+        if (NULL == driver) {
+                printf("Invalid driver registration.\n");
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+        
+        /* Create new device entry */
+        if (NULL == (device = (devmap_device_t *)malloc(sizeof(devmap_device_t)))) {
+                printf("Cannot allocate new device.\n");
+                ipc_answer_fast(iid, ENOMEM, 0, 0);
+                return;
+        }
+        
+        /* Get device name */
+        if (!ipc_data_receive(&callid, &call, NULL, &size)) {
+                free(device);
+                printf("Cannot read device name.\n");
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+        if (size > DEVMAP_NAME_MAXLEN) {
+                printf("Too long device name: %u.\n", size);
+                free(device);
+                ipc_answer_fast(callid, EINVAL, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+                /* +1 for terminating \0 */
+        device->name = (char *)malloc(size + 1);
+
+        if (NULL == device->name) {
+                printf("Cannot read device name.\n");
+                free(device);
+                ipc_answer_fast(callid, ENOMEM, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+        
+        ipc_data_deliver(callid, &call, device->name, size);
+        device->name[size] = 0;
+
+        list_initialize(&(device->devices));
+        list_initialize(&(device->driver_devices));
+
+        futex_down(&devices_list_futex);        
+
+        /* Check that device with such name is not already registered */
+        if (NULL != devmap_device_find_name(device->name)) {
+                printf("Device '%s' already registered.\n", device->name);
+                futex_up(&devices_list_futex);  
+                free(device->name);
+                free(device);
+                ipc_answer_fast(iid, EEXISTS, 0, 0);
+                return;
+        }
+
+        /* Get unique device handle */
+        device->handle = devmap_create_handle(); 
+
+        device->driver = driver;
+        
+        /* Insert device into list of all devices  */
+        list_append(&(device->devices), &devices_list);
+
+        /* Insert device into list of devices that belog to one driver */
+        futex_down(&(device->driver->devices_futex));   
+        
+        list_append(&(device->driver_devices), &(device->driver->devices));
+        
+        futex_up(&(device->driver->devices_futex));     
+        futex_up(&devices_list_futex);  
+
+        printf("Device '%s' registered.\n", device->name);      
+        ipc_answer_fast(iid, EOK, device->handle, 0);
+
+        return;
+}
+
+/**
+ *
+ */
+static int devmap_device_unregister(ipc_callid_t iid, ipc_call_t *icall, 
+        devmap_driver_t *driver)
+{
+        /* TODO */
+
+        return EOK;
+}
+
+/** Connect client to the device.
+ * Find device driver owning requested device and forward
+ * the message to it.
+ *
+ *
+ */
+static void devmap_forward(ipc_callid_t callid, ipc_call_t *call)
+{
+        devmap_device_t *dev;
+        int handle;
+
+        /*
+         * Get handle from request
+         */
+        handle = IPC_GET_ARG1(*call);
+        dev = devmap_device_find_handle(handle);
+
+        if (NULL == dev) {
+                printf("DevMap: No registered device with handle %d.\n", handle);
+                ipc_answer_fast(callid, ENOENT, 0, 0);
+                return;
+        } 
+
+                /* FIXME: is this correct method how to pass argument on forwarding ?*/
+        ipc_forward_fast(callid, dev->driver->phone, (ipcarg_t)(dev->handle), 0);
+        return;
+}
+
+/** Find handle for device instance identified by name.
+ * In answer will be send EOK and device handle in arg1 or a error
+ * code from errno.h. 
+ */
+static void devmap_get_handle(ipc_callid_t iid, ipc_call_t *icall)
+{
+        char *name = NULL;
+        size_t name_size;
+        const devmap_device_t *dev;
+        ipc_callid_t callid;
+        ipc_call_t call;
+        ipcarg_t retval;
+        
+        
+        /* 
+         * Wait for incoming message with device name (but do not
+         * read the name itself until the buffer is allocated).
+         */
+        if (!ipc_data_receive(&callid, &call, NULL, &name_size)) {
+                ipc_answer_fast(callid, EREFUSED, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+        if (name_size > DEVMAP_NAME_MAXLEN) {
+                ipc_answer_fast(callid, EINVAL, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+        /*
+         * Allocate buffer for device name.
+         */
+        if (NULL == (name = (char *)malloc(name_size))) {
+                ipc_answer_fast(callid, ENOMEM, 0, 0);
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }       
+
+        /*
+         * Send confirmation to sender and get data into buffer.
+         */
+        if (EOK != (retval = ipc_data_deliver(callid, &call, name, name_size))) {
+                ipc_answer_fast(iid, EREFUSED, 0, 0);
+                return;
+        }
+
+        /*
+         * Find device name in linked list of known devices.
+         */
+        dev = devmap_device_find_name(name);
+
+        /*
+         * Device was not found.
+         */
+        if (NULL == dev) {
+                printf("DevMap: device %s has not been registered.\n", name);
+                ipc_answer_fast(iid, ENOENT, 0, 0);
+                return;
+        }
+
+        printf("DevMap: device %s has handler %d.\n", name, dev->handle);
+                
+        ipc_answer_fast(iid, EOK, dev->handle, 0);
+
+        return;
+}
+
+/** Find name of device identified by id and send it to caller. 
+ *
+ */
+static void devmap_get_name(ipc_callid_t iid, ipc_call_t *icall) 
+{
+        const devmap_device_t *device;
+        size_t name_size;
+
+        device = devmap_device_find_handle(IPC_GET_ARG1(*icall));
+
+        /*
+         * Device not found.
+         */
+        if (NULL == device) {
+                ipc_answer_fast(iid, ENOENT, 0, 0);
+                return;
+        }       
+
+        ipc_answer_fast(iid, EOK, 0, 0);
+
+        name_size = strlen(device->name);
+
+
+/*      FIXME:
+        we have no channel from DevMap to client -> 
+        sending must be initiated by client
+
+        int rc = ipc_data_send(phone, device->name, name_size); 
+        if (rc != EOK) {
+                async_wait_for(req, NULL);
+                return rc;
+        }
+*/      
+        /* TODO: send name in response */
+
+        return;
+}
+
+/** Handle connection with device driver.
+ *
+ */
+static void
+devmap_connection_driver(ipc_callid_t iid, ipc_call_t *icall)
+{
+        ipc_callid_t callid;
+        ipc_call_t call;
         bool cont = true;
-
-        printf("DevMap: new connection.");
-
-        ipc_answer_fast(iid, EOK, 0, 0); /* Accept connection */
-
+        devmap_driver_t *driver = NULL; 
+
+        ipc_answer_fast(iid, EOK, 0, 0); 
+
+        devmap_driver_register(&driver);
+
+        if (NULL == driver) {
+                printf("DevMap: driver registration failed.\n");
+                return;
+        }
+        
         while (cont) {
                 callid = async_get_call(&call);
@@ -146 +598 @@
                 switch (IPC_GET_METHOD(call)) {
                 case IPC_M_PHONE_HUNGUP:
-                                /* TODO: if its a device connection, remove it from table */
-                        devmap_unregister();
-                        printf("DevMap: connection hung up.");
+                        printf("DevMap: connection hung up.\n");
                         cont = false;
                         continue; /* Exit thread */
-
-                case DEVMAP_REGISTER:
-                        
-                        if ((retval = devmap_register()) != EOK) {
-                                cont = false;
+                case DEVMAP_DRIVER_UNREGISTER:
+                        printf("DevMap: unregister driver.\n");
+                        if (NULL == driver) {
+                                printf("DevMap: driver was not registered!\n");
+                                ipc_answer_fast(callid, ENOENT, 0, 0);
+                        } else {
+                                ipc_answer_fast(callid, EOK, 0, 0);
                         }
                         break;
-                case DEVMAP_UNREGISTER:
-                        /* TODO: remove device (if registred) */
-                        retval = devmap_unregister();
+                case DEVMAP_DEVICE_REGISTER:
+                        /* Register one instance of device */
+                        devmap_device_register(callid, &call, driver);
+                        break;
+                case DEVMAP_DEVICE_UNREGISTER:
+                        /* Remove instance of device identified by handler */
+                        devmap_device_unregister(callid, &call, driver);
+                        break;
+                case DEVMAP_DEVICE_GET_HANDLE:
+                        devmap_get_handle(callid, &call);
+                        break;
+                case DEVMAP_DEVICE_GET_NAME:
+                        devmap_get_handle(callid, &call);
+                        break;
+                default:
+                        if (!(callid & IPC_CALLID_NOTIFICATION)) {
+                                ipc_answer_fast(callid, ENOENT, 0, 0);
+                        }
+                }
+        }
+        
+        if (NULL != driver) {
+                        /* 
+                         * Unregister the device driver and all its devices.
+                         */
+                devmap_driver_unregister(driver);
+                driver = NULL;
+        }
+        
+}
+
+/** Handle connection with device client.
+ *
+ */
+static void
+devmap_connection_client(ipc_callid_t iid, ipc_call_t *icall)
+{
+        ipc_callid_t callid;
+        ipc_call_t call;
+        bool cont = true;
+
+        ipc_answer_fast(iid, EOK, 0, 0); /* Accept connection */
+
+        while (cont) {
+                callid = async_get_call(&call);
+
+                switch (IPC_GET_METHOD(call)) {
+                case IPC_M_PHONE_HUNGUP:
+                        printf("DevMap: connection hung up.\n");
                         cont = false;
-                        break;
-                case DEVMAP_CONNECT_TO_DEVICE:
-                        retval = devmap_forward(IPC_GET_ARG1(call), &call, callid);
-                        cont = false;
-                        break;
-                case DEVMAP_GET_HANDLE:
-                        
+                        continue; /* Exit thread */
+
+                case DEVMAP_DEVICE_CONNECT_ME_TO:
+                        /* Connect client to selected device */
+                        printf("DevMap: connect to device %d.\n", IPC_GET_ARG1(call));
+                        devmap_forward(callid, &call);
+                        break;
+
+                case DEVMAP_DEVICE_GET_HANDLE:
+                        devmap_get_handle(callid, &call);
+
+                        break;
+                case DEVMAP_DEVICE_GET_NAME:
+                        /* TODO */
+                        devmap_get_name(callid, &call);
                         break;
                 default:
-                        retval = ENOENT;
+                        if (!(callid & IPC_CALLID_NOTIFICATION)) {
+                                ipc_answer_fast(callid, ENOENT, 0, 0);
+                        }
                 }
-                ipc_answer_fast(callid, retval, 0, 0);
-        }
-                
-        printf("DevMap: connection closed.");
+        }
+}
+
+/** Function for handling connections to devmap 
+ *
+ */
+static void
+devmap_connection(ipc_callid_t iid, ipc_call_t *icall)
+{
+
+        printf("DevMap: new connection.\n");
+
+                /* Select interface */
+        switch ((ipcarg_t)(IPC_GET_ARG1(*icall))) {
+                case DEVMAP_DRIVER:
+                        devmap_connection_driver(iid, icall);
+                        break;
+                case DEVMAP_CLIENT:
+                        devmap_connection_client(iid, icall);
+                        break;
+                default:
+                        ipc_answer_fast(iid, ENOENT, 0, 0); /* No such interface */
+                        printf("DevMap: Unknown interface %u.\n", \
+                                (ipcarg_t)(IPC_GET_ARG1(*icall)));
+        }
+
+        /* Cleanup */
+        
+        printf("DevMap: connection closed.\n");
         return;
 }
 
-
+/**
+ *
+ */
 int main(int argc, char *argv[])
 {
-
         ipcarg_t phonead;
 
@@ -189 +723 @@
 
         if (devmap_init() != 0) {
-                printf("Error while initializing DevMap service.");
+                printf("Error while initializing DevMap service.\n");
                 return -1;
         }
 
                 /* Set a handler of incomming connections */
-        async_set_client_connection(devmap_client_connection);
+        async_set_client_connection(devmap_connection);
 
                 /* Register device mapper at naming service */

uspace/srv/devmap/devmap.h

@@ -40 +40 @@
 
 typedef enum {
-        DEVMAP_REGISTER = IPC_FIRST_USER_METHOD,
-        DEVMAP_UNREGISTER,
-        DEVMAP_CONNECT_TO_DEVICE,
-        DEVMAP_GET_HANDLE
+        DEVMAP_DRIVER_REGISTER = IPC_FIRST_USER_METHOD,
+        DEVMAP_DRIVER_UNREGISTER,
+        DEVMAP_DEVICE_CONNECT_ME_TO,
+        DEVMAP_DEVICE_REGISTER,
+        DEVMAP_DEVICE_UNREGISTER,
+        DEVMAP_DEVICE_GET_NAME,
+        DEVMAP_DEVICE_GET_HANDLE
 } devmap_request_t;
 
+/** Representation of device driver.
+ * Each driver is responsible for a set of devices.
+ */
+typedef struct {
+                /** Pointers to previous and next drivers in linked list */
+        link_t drivers; 
+                /** Pointer to the linked list of devices controlled by
+                 * this driver */
+        link_t devices;
+                /** Phone asociated with this driver */
+        ipcarg_t phone;
+                /** Device driver name */
+        char *name;     
+                /** Futex for list of devices owned by this driver */
+        atomic_t devices_futex;
+} devmap_driver_t;
 
 /** Info about registered device
@@ -51 +70 @@
  */
 typedef struct {
-        link_t list;
+                /** Pointer to the previous and next device in the list of all devices */
+        link_t devices;
+                /** Pointer to the previous and next device in the list of devices
+                 owned by one driver */
+        link_t driver_devices;
+                /** Unique device identifier  */
         int handle;
+                /** Device name */
         char *name;
-        ipcarg_t phone;
+                /** Device driver handling this device */
+        devmap_driver_t *driver;
 } devmap_device_t;
+
+/** Interface provided by DevMap. 
+ *
+ */
+typedef enum {
+        DEVMAP_DRIVER = 1,
+        DEVMAP_CLIENT
+} devmap_interface_t;
 
 #endif

uspace/srv/ns/ns.c

@@ -213 +213 @@
         }
         hs = hash_table_get_instance(hlp, hashed_service_t, link);
-        return ipc_forward_fast(callid, hs->phone, 0, 0);
+        return ipc_forward_fast(callid, hs->phone, IPC_GET_ARG2(*call), 0);
 }