/*
* Copyright (c) 2006 Ondrej Palkovsky
* 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.
*/
/** @addtogroup libc
* @{
* @}
*/
/** @addtogroup libcipc IPC
* @brief HelenOS uspace IPC
* @{
* @ingroup libc
*/
/** @file
*/
#include <ipc/ipc.h>
#include <libc.h>
#include <malloc.h>
#include <errno.h>
#include <libadt/list.h>
#include <stdio.h>
#include <unistd.h>
#include <futex.h>
#include <kernel/synch/synch.h>
#include <async.h>
#include <fibril.h>
/**
* Structures of this type are used for keeping track of sent asynchronous calls
* and queing unsent calls.
*/
typedef struct {
link_t list;
ipc_async_callback_t callback;
void *private;
union {
ipc_callid_t callid;
struct {
ipc_call_t data;
int phoneid;
} msg;
} u;
fid_t fid; /**< Fibril waiting for sending this call. */
} async_call_t;
LIST_INITIALIZE(dispatched_calls);
/** List of asynchronous calls that were not accepted by kernel.
*
* It is protected by async_futex, because if the call cannot be sent into the
* kernel, the async framework is used automatically.
*/
LIST_INITIALIZE(queued_calls);
static atomic_t ipc_futex = FUTEX_INITIALIZER;
/** Make a fast synchronous call.
*
* Only one payload argument can be passed using this function. However, this
* function is faster than the generic ipc_call_sync_3().
*
* @param phoneid Phone handle for the call.
* @param method Requested method.
* @param arg1 Service-defined payload argument.
* @param result If non-NULL, the return ARG1 will be stored there.
*
* @return Negative values represent errors returned by IPC.
* Otherwise the RETVAL of the answer is returned.
*/
int ipc_call_sync(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t *result)
{
ipc_call_t resdata;
int callres;
callres = __SYSCALL4(SYS_IPC_CALL_SYNC_FAST, phoneid, method, arg1,
(sysarg_t) &resdata);
if (callres)
return callres;
if (result)
*result = IPC_GET_ARG1(resdata);
return IPC_GET_RETVAL(resdata);
}
/** Make a synchronous call transmitting 3 arguments of payload.
*
* @param phoneid Phone handle for the call.
* @param method Requested method.
* @param arg1 Service-defined payload argument.
* @param arg2 Service-defined payload argument.
* @param arg3 Service-defined payload argument.
* @param result1 If non-NULL, storage for the first return argument.
* @param result2 If non-NULL, storage for the second return argument.
* @param result3 If non-NULL, storage for the third return argument.
*
* @return Negative value means IPC error.
* Otherwise the RETVAL of the answer.
*/
int ipc_call_sync_3(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
ipcarg_t arg3, ipcarg_t *result1, ipcarg_t *result2, ipcarg_t *result3)
{
ipc_call_t data;
int callres;
IPC_SET_METHOD(data, method);
IPC_SET_ARG1(data, arg1);
IPC_SET_ARG2(data, arg2);
IPC_SET_ARG3(data, arg3);
callres = __SYSCALL3(SYS_IPC_CALL_SYNC, phoneid, (sysarg_t) &data,
(sysarg_t) &data);
if (callres)
return callres;
if (result1)
*result1 = IPC_GET_ARG1(data);
if (result2)
*result2 = IPC_GET_ARG2(data);
if (result3)
*result3 = IPC_GET_ARG3(data);
return IPC_GET_RETVAL(data);
}
/** Syscall to send asynchronous message.
*
* @param phoneid Phone handle for the call.
* @param data Call data with the request.
*
* @return Hash of the call or an error code.
*/
static ipc_callid_t _ipc_call_async(int phoneid, ipc_call_t *data)
{
return __SYSCALL2(SYS_IPC_CALL_ASYNC, phoneid, (sysarg_t) data);
}
/** Prolog to ipc_call_async_*() functions.
*
* @param private Argument for the answer/error callback.
* @param callback Answer/error callback.
*
* @return New, partially initialized async_call structure or NULL.
*/
static inline async_call_t *ipc_prepare_async(void *private,
ipc_async_callback_t callback)
{
async_call_t *call;
if (!call) {
if (callback)
callback(private, ENOMEM, NULL);
return NULL;
}
call->callback = callback;
call->private = private;
return call;
}
/** Epilogue of ipc_call_async_*() functions.
*
* @param callid Value returned by the SYS_IPC_CALL_ASYNC_* syscall.
* @param phoneid Phone handle through which the call was made.
* @param call async_call structure returned by ipc_prepare_async().
* @param can_preempt If non-zero, the current pseudo thread can be preempted
* in this call.
*/
static inline void ipc_finish_async(ipc_callid_t callid, int phoneid,
async_call_t *call, int can_preempt)
{
if (!call) { /* Nothing to do regardless if failed or not */
futex_up(&ipc_futex);
return;
}
if (callid == IPC_CALLRET_FATAL) {
futex_up(&ipc_futex);
/* Call asynchronous handler with error code */
if (call->callback)
call->callback(call->private, ENOENT, NULL);
return;
}
if (callid == IPC_CALLRET_TEMPORARY) {
futex_up(&ipc_futex);
call->u.msg.phoneid = phoneid;
futex_down(&async_futex);
list_append(&call->list, &queued_calls);
if (can_preempt) {
call->fid = fibril_get_id();
fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
/* Async futex unlocked by previous call */
} else {
call->fid = 0;
futex_up(&async_futex);
}
return;
}
call->u.callid = callid;
/* Add call to the list of dispatched calls */
list_append(&call->list, &dispatched_calls);
futex_up(&ipc_futex);
}
/** Make a fast asynchronous call.
*
* This function can only handle two arguments of payload. It is, however,
* faster than the more generic ipc_call_async_3().
*
* Note that this function is a void function.
* During normal opertation, answering this call will trigger the callback.
* In case of fatal error, call the callback handler with the proper error code.
* If the call cannot be temporarily made, queue it.
*
* @param phoneid Phone handle for the call.
* @param method Requested method.
* @param arg1 Service-defined payload argument.
* @param arg2 Service-defined payload argument.
* @param private Argument to be passed to the answer/error callback.
* @param callback Answer or error callback.
* @param can_preempt If non-zero, the current pseudo thread will be preempted
* in case the kernel temporarily refuses to accept more
* asynchronous calls.
*/
void ipc_call_async_2(int phoneid, ipcarg_t method, ipcarg_t arg1,
ipcarg_t arg2, void *private, ipc_async_callback_t callback,
int can_preempt)
{
async_call_t *call = NULL;
ipc_callid_t callid;
if (callback) {
call = ipc_prepare_async(private, callback);
if (!call)
return;
}
/*
* We need to make sure that we get callid before another thread
* accesses the queue again.
*/
futex_down(&ipc_futex);
callid = __SYSCALL4(SYS_IPC_CALL_ASYNC_FAST, phoneid, method, arg1,
arg2);
if (callid == IPC_CALLRET_TEMPORARY) {
if (!call) {
call = ipc_prepare_async(private, callback);
if (!call)
return;
}
IPC_SET_METHOD(call->u.msg.data, method);
IPC_SET_ARG1(call->u.msg.data, arg1);
IPC_SET_ARG2(call->u.msg.data, arg2);
}
ipc_finish_async(callid, phoneid, call, can_preempt);
}
/** Make an asynchronous call transmitting the entire payload.
*
* Note that this function is a void function.
* During normal opertation, answering this call will trigger the callback.
* In case of fatal error, call the callback handler with the proper error code.
* If the call cannot be temporarily made, queue it.
*
* @param phoneid Phone handle for the call.
* @param method Requested method.
* @param arg1 Service-defined payload argument.
* @param arg2 Service-defined payload argument.
* @param arg3 Service-defined payload argument.
* @param private Argument to be passed to the answer/error callback.
* @param callback Answer or error callback.
* @param can_preempt If non-zero, the current pseudo thread will be preempted
* in case the kernel temporarily refuses to accept more
* asynchronous calls.
*
*/
void ipc_call_async_3(int phoneid, ipcarg_t method, ipcarg_t arg1,
ipcarg_t arg2, ipcarg_t arg3, void *private, ipc_async_callback_t callback,
int can_preempt)
{
async_call_t *call;
ipc_callid_t callid;
call = ipc_prepare_async(private, callback);
if (!call)
return;
IPC_SET_METHOD(call->u.msg.data, method);
IPC_SET_ARG1(call->u.msg.data, arg1);
IPC_SET_ARG2(call->u.msg.data, arg2);
IPC_SET_ARG3(call->u.msg.data, arg3);
/*
* We need to make sure that we get callid before another thread accesses
* the queue again.
*/
futex_down(&ipc_futex);
callid = _ipc_call_async(phoneid, &call->u.msg.data);
ipc_finish_async(callid, phoneid, call, can_preempt);
}
/** Answer a received call - fast version.
*
* The fast answer makes use of passing retval and first two arguments in
* registers. If you need to return more, use the ipc_answer() instead.
*
* @param callid Hash of the call being answered.
* @param retval Return value.
* @param arg1 First return argument.
* @param arg2 Second return argument.
*
* @return Zero on success or a value from @ref errno.h on failure.
*/
ipcarg_t ipc_answer_fast(ipc_callid_t callid, ipcarg_t retval, ipcarg_t arg1,
ipcarg_t arg2)
{
return __SYSCALL4(SYS_IPC_ANSWER_FAST, callid, retval, arg1, arg2);
}
/** Answer a received call - full version.
*
* @param callid Hash of the call being answered.
* @param call Call structure with the answer.
* Must be already initialized by the responder.
*
* @return Zero on success or a value from @ref errno.h on failure.
*/
ipcarg_t ipc_answer(ipc_callid_t callid, ipc_call_t *call)
{
return __SYSCALL2(SYS_IPC_ANSWER, callid, (sysarg_t) call);
}
/** Try to dispatch queued calls from the async queue. */
static void try_dispatch_queued_calls(void)
{
async_call_t *call;
ipc_callid_t callid;
/** @todo
* Integrate intelligently ipc_futex, so that it is locked during
* ipc_call_async_*(), until it is added to dispatched_calls.
*/
futex_down(&async_futex);
while (!list_empty(&queued_calls)) {
call = list_get_instance(queued_calls.next, async_call_t, list);
callid = _ipc_call_async(call->u.msg.phoneid, &call->u.msg.data);
if (callid == IPC_CALLRET_TEMPORARY) {
break;
}
list_remove(&call->list);
futex_up(&async_futex);
if (call->fid)
fibril_add_ready(call->fid);
if (callid == IPC_CALLRET_FATAL) {
if (call->callback)
call->callback(call->private, ENOENT, NULL);
} else {
call->u.callid = callid;
futex_down(&ipc_futex);
list_append(&call->list, &dispatched_calls);
futex_up(&ipc_futex);
}
futex_down(&async_futex);
}
futex_up(&async_futex);
}
/** Handle a received answer.
*
* Find the hash of the answer and call the answer callback.
*
* @todo Make it use hash table.
*
* @param callid Hash of the received answer.
* The answer has the same hash as the request OR'ed with
* the IPC_CALLID_ANSWERED bit.
* @param data Call data of the answer.
*/
static void handle_answer(ipc_callid_t callid, ipc_call_t *data)
{
link_t *item;
async_call_t *call;
callid &= ~IPC_CALLID_ANSWERED;
futex_down(&ipc_futex);
for (item = dispatched_calls.next; item != &dispatched_calls;
item = item->next) {
call = list_get_instance(item, async_call_t, list);
if (call->u.callid == callid) {
list_remove(&call->list);
futex_up(&ipc_futex);
if (call->callback)
call->callback(call->private,
IPC_GET_RETVAL(*data), data);
return;
}
}
futex_up(&ipc_futex);
}
/** Wait for a first call to come.
*
* @param call Storage where the incoming call data will be stored.
* @param usec Timeout in microseconds
* @param flags Flags passed to SYS_IPC_WAIT (blocking, nonblocking).
*
* @return Hash of the call. Note that certain bits have special
* meaning. IPC_CALLID_ANSWERED will be set in an answer
* and IPC_CALLID_NOTIFICATION is used for notifications.
*
*/
ipc_callid_t ipc_wait_cycle(ipc_call_t *call, uint32_t usec, int flags)
{
ipc_callid_t callid;
callid = __SYSCALL3(SYS_IPC_WAIT, (sysarg_t) call, usec, flags);
/* Handle received answers */
if (callid & IPC_CALLID_ANSWERED) {
handle_answer(callid, call);
try_dispatch_queued_calls();
}
return callid;
}
/** Wait some time for an IPC call.
*
* The call will return after an answer is received.
*
* @param call Storage where the incoming call data will be stored.
* @param usec Timeout in microseconds.
*
* @return Hash of the answer.
*/
ipc_callid_t ipc_wait_for_call_timeout(ipc_call_t *call, uint32_t usec)
{
ipc_callid_t callid;
do {
callid = ipc_wait_cycle(call, usec, SYNCH_FLAGS_NONE);
} while (callid & IPC_CALLID_ANSWERED);
return callid;
}
/** Check if there is an IPC call waiting to be picked up.
*
* @param call Storage where the incoming call will be stored.
* @return Hash of the answer.
*/
ipc_callid_t ipc_trywait_for_call(ipc_call_t *call)
{
ipc_callid_t callid;
do {
callid = ipc_wait_cycle(call, SYNCH_NO_TIMEOUT,
SYNCH_FLAGS_NON_BLOCKING);
} while (callid & IPC_CALLID_ANSWERED);
return callid;
}
/** Ask destination to do a callback connection.
*
* @param phoneid Phone handle used for contacting the other side.
* @param arg1 Service-defined argument.
* @param arg2 Service-defined argument.
* @param phonehash Storage where the library will store an opaque
* identifier of the phone that will be used for incoming
* calls. This identifier can be used for connection
* tracking.
*
* @return Zero on success or a negative error code.
*/
int ipc_connect_to_me(int phoneid, int arg1, int arg2, ipcarg_t *phonehash)
{
return ipc_call_sync_3(phoneid, IPC_M_CONNECT_TO_ME, arg1, arg2, 0, 0, 0,
phonehash);
}
/** Ask through phone for a new connection to some service.
*
* @param phoneid Phone handle used for contacting the other side.
* @param arg1 User defined argument.
* @param arg2 User defined argument.
*
* @return New phone handle on success or a negative error code.
*/
int ipc_connect_me_to(int phoneid, int arg1, int arg2)
{
ipcarg_t newphid;
int res;
res = ipc_call_sync_3(phoneid, IPC_M_CONNECT_ME_TO, arg1, arg2, 0, 0, 0,
&newphid);
if (res)
return res;
return newphid;
}
/** Hang up a phone.
*
* @param phoneid Handle of the phone to be hung up.
*
* @return Zero on success or a negative error code.
*/
int ipc_hangup(int phoneid)
{
return __SYSCALL1(SYS_IPC_HANGUP, phoneid);
}
/** Register IRQ notification.
*
* @param inr IRQ number.
* @param devno Device number of the device generating inr.
* @param method Use this method for notifying me.
* @param ucode Top-half pseudocode handler.
*
* @return Value returned by the kernel.
*/
int ipc_register_irq(int inr, int devno, int method, irq_code_t *ucode)
{
return __SYSCALL4(SYS_IPC_REGISTER_IRQ, inr, devno, method,
(sysarg_t) ucode);
}
/** Unregister IRQ notification.
*
* @param inr IRQ number.
* @param devno Device number of the device generating inr.
*
* @return Value returned by the kernel.
*/
int ipc_unregister_irq(int inr, int devno)
{
return __SYSCALL2(SYS_IPC_UNREGISTER_IRQ, inr, devno);
}
/** Forward a received call to another destination.
*
* @param callid Hash of the call to forward.
* @param phoneid Phone handle to use for forwarding.
* @param method New method for the forwarded call.
* @param arg1 New value of the first argument for the forwarded call.
*
* @return Zero on success or an error code.
*
* For non-system methods, the old method and arg1 are rewritten by the new
* values. For system methods, the new method and arg1 are written to the old
* arg1 and arg2, respectivelly.
*/
int ipc_forward_fast(ipc_callid_t callid, int phoneid, int method, ipcarg_t arg1)
{
return __SYSCALL4(SYS_IPC_FORWARD_FAST, callid, phoneid, method, arg1);
}
/** @}
*/