0,0 → 1,694 |
/* |
* Copyright (c) 2007 Josef Cejka |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - Redistributions in binary form must reproduce the above copyright |
* notice, this list of conditions and the following disclaimer in the |
* documentation and/or other materials provided with the distribution. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
*/ |
|
/** |
* @defgroup devmap Device mapper. |
* @brief HelenOS device mapper. |
* @{ |
*/ |
|
/** @file |
*/ |
|
#include <ipc/services.h> |
#include <ipc/ns.h> |
#include <async.h> |
#include <stdio.h> |
#include <errno.h> |
#include <bool.h> |
#include <futex.h> |
#include <stdlib.h> |
#include <string.h> |
#include <ipc/devmap.h> |
|
#define NAME "devmap" |
|
|
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. |
* |
* |
*/ |
static int devmap_init() |
{ |
/* TODO: */ |
|
return EOK; |
} |
|
/** 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) |
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. 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); |
|
|
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; |
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); |
ipc_answer_0(callid, EREFUSED); |
ipc_answer_0(iid, EREFUSED); |
return; |
} |
|
if (name_size > DEVMAP_NAME_MAXLEN) { |
free(driver); |
ipc_answer_0(callid, EINVAL); |
ipc_answer_0(iid, EREFUSED); |
return; |
} |
|
/* |
* Allocate buffer for device name. |
*/ |
if (NULL == (driver->name = (char *)malloc(name_size + 1))) { |
free(driver); |
ipc_answer_0(callid, ENOMEM); |
ipc_answer_0(iid, EREFUSED); |
return; |
} |
|
/* |
* Send confirmation to sender and get data into buffer. |
*/ |
if (EOK != ipc_data_write_finalize(callid, driver->name, name_size)) { |
free(driver->name); |
free(driver); |
ipc_answer_0(iid, EREFUSED); |
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 |
*/ |
callid = async_get_call(&call); |
|
if (IPC_M_CONNECT_TO_ME != IPC_GET_METHOD(call)) { |
ipc_answer_0(callid, ENOTSUP); |
|
free(driver->name); |
free(driver); |
ipc_answer_0(iid, ENOTSUP); |
return; |
} |
|
driver->phone = IPC_GET_ARG5(call); |
|
ipc_answer_0(callid, EOK); |
|
list_initialize(&(driver->drivers)); |
|
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); |
|
ipc_answer_0(iid, EOK); |
|
*odriver = 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) |
return EEXISTS; |
|
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); |
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); |
|
return EOK; |
} |
|
|
/** 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; |
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); |
ipc_answer_0(iid, EREFUSED); |
return; |
} |
|
if (size > DEVMAP_NAME_MAXLEN) { |
free(device); |
ipc_answer_0(callid, EINVAL); |
ipc_answer_0(iid, EREFUSED); |
return; |
} |
|
/* +1 for terminating \0 */ |
device->name = (char *) malloc(size + 1); |
|
if (NULL == device->name) { |
free(device); |
ipc_answer_0(callid, ENOMEM); |
ipc_answer_0(iid, EREFUSED); |
return; |
} |
|
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); |
|
/* Check that device with such name is not already registered */ |
if (NULL != devmap_device_find_name(device->name)) { |
printf(NAME ": Device '%s' already registered\n", device->name); |
futex_up(&devices_list_futex); |
free(device->name); |
free(device); |
ipc_answer_0(iid, EEXISTS); |
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); |
|
ipc_answer_1(iid, EOK, device->handle); |
} |
|
/** |
* |
*/ |
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_ARG2(*call); |
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); |
} |
|
/** 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; |
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_answer_0(callid, EREFUSED); |
ipc_answer_0(iid, EREFUSED); |
return; |
} |
|
if (name_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))) { |
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; |
} |
|
/* |
* Find device name in linked list of known devices. |
*/ |
dev = devmap_device_find_name(name); |
|
/* |
* Device was not found. |
*/ |
if (NULL == dev) { |
ipc_answer_0(iid, ENOENT); |
return; |
} |
|
ipc_answer_1(iid, EOK, dev->handle); |
} |
|
/** 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_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; |
} |
*/ |
/* TODO: send name in response */ |
} |
|
/** 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; |
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)) { |
case IPC_M_PHONE_HUNGUP: |
cont = false; |
continue; /* Exit thread */ |
case DEVMAP_DRIVER_UNREGISTER: |
if (NULL == driver) { |
ipc_answer_0(callid, ENOENT); |
} else { |
ipc_answer_0(callid, EOK); |
} |
break; |
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_0(callid, ENOENT); |
} |
} |
} |
|
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_0(iid, EOK); /* Accept connection */ |
|
while (cont) { |
callid = async_get_call(&call); |
|
switch (IPC_GET_METHOD(call)) { |
case IPC_M_PHONE_HUNGUP: |
cont = false; |
continue; /* Exit thread */ |
|
case DEVMAP_DEVICE_GET_HANDLE: |
devmap_get_handle(callid, &call); |
|
break; |
case DEVMAP_DEVICE_GET_NAME: |
/* TODO */ |
devmap_get_name(callid, &call); |
break; |
default: |
if (!(callid & IPC_CALLID_NOTIFICATION)) { |
ipc_answer_0(callid, ENOENT); |
} |
} |
} |
} |
|
/** Function for handling connections to devmap |
* |
*/ |
static void devmap_connection(ipc_callid_t iid, ipc_call_t *icall) |
{ |
/* 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; |
case DEVMAP_CONNECT_TO_DEVICE: |
/* Connect client to selected device */ |
devmap_forward(iid, icall); |
break; |
default: |
ipc_answer_0(iid, ENOENT); /* No such interface */ |
} |
|
/* Cleanup */ |
} |
|
/** |
* |
*/ |
int main(int argc, char *argv[]) |
{ |
printf(NAME ": HelenOS Device Mapper\n"); |
|
ipcarg_t phonead; |
|
if (devmap_init() != 0) { |
printf(NAME ": Error while initializing service\n"); |
return -1; |
} |
|
/* Set a handler of incomming connections */ |
async_set_client_connection(devmap_connection); |
|
/* Register device mapper at naming service */ |
if (ipc_connect_to_me(PHONE_NS, SERVICE_DEVMAP, 0, 0, &phonead) != 0) |
return -1; |
|
printf(NAME ": Accepting connections\n"); |
async_manager(); |
/* Never reached */ |
return 0; |
} |
|
/** |
* @} |
*/ |