Index: uspace/srv/devmap/devmap.c =================================================================== --- uspace/srv/devmap/devmap.c (revision 1fcfc940d5ec6d6e9be0da114b9324a0b30b41c6) +++ uspace/srv/devmap/devmap.c (revision 6519d6f5a49b667921f83081e2ebb90b80c86500) @@ -29,7 +29,7 @@ /** * @defgroup devmap Device mapper. - * @brief HelenOS device mapper. + * @brief HelenOS device mapper. * @{ - */ + */ /** @file @@ -47,15 +47,22 @@ #include -#define NAME "devmap" - +#define NAME "devmap" + +/** Pending lookup structure. */ +typedef struct { + link_t link; + char *name; /**< Device name */ + ipc_callid_t callid; /**< Call ID waiting for the lookup */ +} pending_req_t; 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 +LIST_INITIALIZE(pending_req); + +/* Locking order: + * drivers_list_futex + * devices_list_futex + * (devmap_driver_t *)->devices_futex + * create_handle_futex **/ @@ -64,25 +71,26 @@ 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 */ + * and implement some version of LRU algorithm + */ + /* FIXME: overflow */ - futex_down(&create_handle_futex); - + futex_down(&create_handle_futex); + last_handle += 1; handle = last_handle; - - futex_up(&create_handle_futex); - + + futex_up(&create_handle_futex); + return handle; } -/** Initialize device mapper. +/** Initialize device mapper. * * @@ -91,5 +99,5 @@ { /* TODO: */ - + return EOK; } @@ -100,21 +108,17 @@ static devmap_device_t *devmap_device_find_name(const char *name) { - link_t *item; + link_t *item = devices_list.next; 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; - } + if (0 == strcmp(device->name, name)) + break; item = item->next; } - + if (item == &devices_list) return NULL; - + device = list_get_instance(item, devmap_device_t, devices); return device; @@ -122,84 +126,81 @@ /** Find device with given handle. + * * @todo: use hash table + * */ static devmap_device_t *devmap_device_find_handle(int handle) { - link_t *item; + futex_down(&devices_list_futex); + + link_t *item = (&devices_list)->next; 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; - } + 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. It's 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->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) { + *odriver = NULL; + + ipc_call_t icall; + ipc_callid_t iid = async_get_call(&icall); + + if (IPC_GET_METHOD(icall) != DEVMAP_DRIVER_REGISTER) { + ipc_answer_0(iid, EREFUSED); + return; + } + + devmap_driver_t *driver = (devmap_driver_t *) malloc(sizeof(devmap_driver_t)); + + if (driver == NULL) { + ipc_answer_0(iid, ENOMEM); + return; + } + + /* + * Get driver name + */ + ipc_callid_t callid; size_t name_size; - ipc_callid_t callid; - ipc_call_t call; - 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_0(iid, EREFUSED); - return; - } - - if (NULL == - (driver = (devmap_driver_t *)malloc(sizeof(devmap_driver_t)))) { - ipc_answer_0(iid, ENOMEM); - return; - } - - /* - * Get driver name - */ if (!ipc_data_write_receive(&callid, &name_size)) { free(driver); @@ -208,5 +209,5 @@ return; } - + if (name_size > DEVMAP_NAME_MAXLEN) { free(driver); @@ -215,15 +216,16 @@ return; } - + /* * Allocate buffer for device name. */ - if (NULL == (driver->name = (char *)malloc(name_size + 1))) { + driver->name = (char *) malloc(name_size + 1); + if (driver->name == NULL) { free(driver); ipc_answer_0(callid, ENOMEM); ipc_answer_0(iid, EREFUSED); return; - } - + } + /* * Send confirmation to sender and get data into buffer. @@ -235,20 +237,21 @@ return; } - + driver->name[name_size] = 0; - + /* 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 */ + ipc_call_t call; callid = async_get_call(&call); - + if (IPC_M_CONNECT_TO_ME != IPC_GET_METHOD(call)) { ipc_answer_0(callid, ENOTSUP); @@ -259,5 +262,5 @@ return; } - + driver->phone = IPC_GET_ARG5(call); @@ -265,46 +268,46 @@ list_initialize(&(driver->drivers)); - - futex_down(&drivers_list_futex); + + futex_down(&drivers_list_futex); /* TODO: * check that no driver with name equal to driver->name is registered */ - - /* + + /* * Insert new driver into list of registered drivers */ list_append(&(driver->drivers), &drivers_list); - futex_up(&drivers_list_futex); + futex_up(&drivers_list_futex); ipc_answer_0(iid, EOK); - + *odriver = driver; } -/** Unregister device driver, unregister all its devices and free driver +/** + * 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) + if (driver == NULL) return EEXISTS; - futex_down(&drivers_list_futex); - + 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(&devices_list_futex); futex_down(&(driver->devices_futex)); - + while (!list_empty(&(driver->devices))) { - device = list_get_instance(driver->devices.next, + devmap_device_t *device = list_get_instance(driver->devices.next, devmap_device_t, driver_devices); devmap_device_unregister_core(device); @@ -312,15 +315,37 @@ futex_up(&(driver->devices_futex)); - futex_up(&devices_list_futex); - futex_up(&drivers_list_futex); - + futex_up(&devices_list_futex); + futex_up(&drivers_list_futex); + /* free name and driver */ - if (NULL != driver->name) { + if (NULL != driver->name) free(driver->name); - } - + free(driver); - + return EOK; +} + + +/** Process pending lookup requests */ +static void process_pending_lookup() +{ + link_t *cur; + +loop: + for (cur = pending_req.next; cur != &pending_req; cur = cur->next) { + pending_req_t *pr = list_get_instance(cur, pending_req_t, link); + + const devmap_device_t *dev = devmap_device_find_name(pr->name); + if (!dev) + continue; + + ipc_answer_1(pr->callid, EOK, dev->handle); + + free(pr->name); + list_remove(cur); + free(pr); + goto loop; + } } @@ -332,21 +357,19 @@ devmap_driver_t *driver) { + if (driver == NULL) { + ipc_answer_0(iid, EREFUSED); + return; + } + + /* Create new device entry */ + devmap_device_t *device = (devmap_device_t *) malloc(sizeof(devmap_device_t)); + if (device == NULL) { + ipc_answer_0(iid, ENOMEM); + return; + } + + /* Get device name */ ipc_callid_t callid; size_t size; - devmap_device_t *device; - - if (NULL == driver) { - ipc_answer_0(iid, EREFUSED); - return; - } - - /* Create new device entry */ - if (NULL == - (device = (devmap_device_t *) malloc(sizeof(devmap_device_t)))) { - ipc_answer_0(iid, ENOMEM); - return; - } - - /* Get device name */ if (!ipc_data_write_receive(&callid, &size)) { free(device); @@ -354,5 +377,5 @@ return; } - + if (size > DEVMAP_NAME_MAXLEN) { free(device); @@ -364,6 +387,6 @@ /* +1 for terminating \0 */ device->name = (char *) malloc(size + 1); - - if (NULL == device->name) { + + if (device->name == NULL) { free(device); ipc_answer_0(callid, ENOMEM); @@ -374,10 +397,10 @@ ipc_data_write_finalize(callid, device->name, size); device->name[size] = 0; - + list_initialize(&(device->devices)); list_initialize(&(device->driver_devices)); - - futex_down(&devices_list_futex); - + + futex_down(&devices_list_futex); + /* Check that device with such name is not already registered */ if (NULL != devmap_device_find_name(device->name)) { @@ -389,13 +412,13 @@ return; } - + /* Get unique device handle */ - device->handle = devmap_create_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); @@ -403,8 +426,10 @@ list_append(&device->driver_devices, &device->driver->devices); - futex_up(&device->driver->devices_futex); - futex_up(&devices_list_futex); - + futex_up(&device->driver->devices_futex); + futex_up(&devices_list_futex); + ipc_answer_1(iid, EOK, device->handle); + + process_pending_lookup(); } @@ -416,28 +441,26 @@ { /* 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_ARG2(*call); - dev = devmap_device_find_handle(handle); - + int handle = IPC_GET_ARG2(*call); + devmap_device_t *dev = devmap_device_find_handle(handle); + if (NULL == dev) { ipc_answer_0(callid, ENOENT); return; - } - + } + ipc_forward_fast(callid, dev->driver->phone, (ipcarg_t)(dev->handle), IPC_GET_ARG3(*call), 0, IPC_FF_NONE); @@ -445,98 +468,113 @@ /** 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. + * 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; - 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_write_receive(&callid, &name_size)) { + ipc_callid_t callid; + size_t size; + if (!ipc_data_write_receive(&callid, &size)) { ipc_answer_0(callid, EREFUSED); ipc_answer_0(iid, EREFUSED); return; } - - if (name_size > DEVMAP_NAME_MAXLEN) { + + if ((size < 1) || (size > DEVMAP_NAME_MAXLEN)) { ipc_answer_0(callid, EINVAL); ipc_answer_0(iid, EREFUSED); return; } - + /* * Allocate buffer for device name. */ - if (NULL == (name = (char *)malloc(name_size))) { + char *name = (char *) malloc(size); + if (name == NULL) { ipc_answer_0(callid, ENOMEM); ipc_answer_0(iid, EREFUSED); return; - } - + } + /* * Send confirmation to sender and get data into buffer. */ - if (EOK != (retval = ipc_data_write_finalize(callid, name, - name_size))) { - ipc_answer_0(iid, EREFUSED); - return; - } - + ipcarg_t retval = ipc_data_write_finalize(callid, name, size); + if (retval != EOK) { + ipc_answer_0(iid, EREFUSED); + free(name); + return; + } + name[size] = '\0'; + /* * Find device name in linked list of known devices. */ - dev = devmap_device_find_name(name); - + const devmap_device_t *dev = devmap_device_find_name(name); + /* * Device was not found. */ - if (NULL == dev) { + if (dev == NULL) { + if (IPC_GET_ARG1(*icall) & IPC_FLAG_BLOCKING) { + /* Blocking lookup, add to pending list */ + pending_req_t *pr = (pending_req_t *) malloc(sizeof(pending_req_t)); + if (!pr) { + ipc_answer_0(iid, ENOMEM); + free(name); + return; + } + + pr->name = name; + pr->callid = iid; + list_append(&pr->link, &pending_req); + return; + } + ipc_answer_0(iid, ENOENT); - return; - } - + free(name); + return; + } + ipc_answer_1(iid, EOK, dev->handle); -} - -/** Find name of device identified by id and send it to caller. + free(name); +} + +/** 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)); - + const devmap_device_t *device = devmap_device_find_handle(IPC_GET_ARG1(*icall)); + /* * Device not found. */ - if (NULL == device) { + if (device == NULL) { ipc_answer_0(iid, ENOENT); return; - } - + } + ipc_answer_0(iid, EOK); - - name_size = strlen(device->name); - - -/* FIXME: - we have no channel from DEVMAP to client -> - sending must be initiated by client - - int rc = ipc_data_write_send(phone, device->name, name_size); - if (rc != EOK) { - async_wait_for(req, NULL); - return rc; - } -*/ + + size_t name_size = strlen(device->name); + + /* FIXME: + * We have no channel from DEVMAP to client, therefore + * sending must be initiated by client. + * + * int rc = ipc_data_write_send(phone, device->name, name_size); + * if (rc != EOK) { + * async_wait_for(req, NULL); + * return rc; + * } + */ + /* TODO: send name in response */ } @@ -547,29 +585,28 @@ static void devmap_connection_driver(ipc_callid_t iid, ipc_call_t *icall) { - ipc_callid_t callid; - ipc_call_t call; + /* Accept connection */ + ipc_answer_0(iid, EOK); + + devmap_driver_t *driver = NULL; + devmap_driver_register(&driver); + + if (NULL == driver) + return; + bool cont = true; - devmap_driver_t *driver = NULL; - - ipc_answer_0(iid, EOK); - - devmap_driver_register(&driver); - - if (NULL == driver) - return; - while (cont) { - callid = async_get_call(&call); - - switch (IPC_GET_METHOD(call)) { + ipc_call_t call; + ipc_callid_t callid = async_get_call(&call); + + switch (IPC_GET_METHOD(call)) { case IPC_M_PHONE_HUNGUP: cont = false; - continue; /* Exit thread */ + /* Exit thread */ + continue; case DEVMAP_DRIVER_UNREGISTER: - if (NULL == driver) { + if (NULL == driver) ipc_answer_0(callid, ENOENT); - } else { + else ipc_answer_0(callid, EOK); - } break; case DEVMAP_DEVICE_REGISTER: @@ -588,12 +625,11 @@ break; default: - if (!(callid & IPC_CALLID_NOTIFICATION)) { + if (!(callid & IPC_CALLID_NOTIFICATION)) ipc_answer_0(callid, ENOENT); - } } } if (NULL != driver) { - /* + /* * Unregister the device driver and all its devices. */ @@ -601,5 +637,4 @@ driver = NULL; } - } @@ -609,21 +644,19 @@ static void devmap_connection_client(ipc_callid_t iid, ipc_call_t *icall) { - ipc_callid_t callid; - ipc_call_t call; + /* Accept connection */ + ipc_answer_0(iid, EOK); + bool cont = true; - - ipc_answer_0(iid, EOK); /* Accept connection */ - while (cont) { - callid = async_get_call(&call); - - switch (IPC_GET_METHOD(call)) { + ipc_call_t call; + ipc_callid_t callid = async_get_call(&call); + + switch (IPC_GET_METHOD(call)) { case IPC_M_PHONE_HUNGUP: cont = false; - continue; /* Exit thread */ - + /* Exit thread */ + continue; case DEVMAP_DEVICE_GET_HANDLE: - devmap_get_handle(callid, &call); - + devmap_get_handle(callid, &call); break; case DEVMAP_DEVICE_GET_NAME: @@ -632,12 +665,11 @@ break; default: - if (!(callid & IPC_CALLID_NOTIFICATION)) { + if (!(callid & IPC_CALLID_NOTIFICATION)) ipc_answer_0(callid, ENOENT); - } } } } -/** Function for handling connections to devmap +/** Function for handling connections to devmap * */ @@ -657,8 +689,7 @@ break; default: - ipc_answer_0(iid, ENOENT); /* No such interface */ - } - - /* Cleanup */ + /* No such interface */ + ipc_answer_0(iid, ENOENT); + } } @@ -670,6 +701,4 @@ printf(NAME ": HelenOS Device Mapper\n"); - ipcarg_t phonead; - if (devmap_init() != 0) { printf(NAME ": Error while initializing service\n"); @@ -679,6 +708,7 @@ /* Set a handler of incomming connections */ async_set_client_connection(devmap_connection); - + /* Register device mapper at naming service */ + ipcarg_t phonead; if (ipc_connect_to_me(PHONE_NS, SERVICE_DEVMAP, 0, 0, &phonead) != 0) return -1; @@ -686,4 +716,5 @@ printf(NAME ": Accepting connections\n"); async_manager(); + /* Never reached */ return 0;