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Ignore whitespace Rev 1786 → Rev 1787

/trunk/uspace/libc/generic/ipc.c
0,0 → 1,472
/*
* 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 <psthread.h>
 
/** Structure used for keeping track of sent async msgs
* and queing unsent msgs
*
*/
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;
pstid_t ptid; /**< Thread waiting for sending this msg */
} async_call_t;
 
LIST_INITIALIZE(dispatched_calls);
 
/* queued_calls is protcted by async_futex, because if the
* call cannot be sent into kernel, async framework is used
* automatically
*/
LIST_INITIALIZE(queued_calls); /**< List of async calls that were not accepted
* by kernel */
 
static atomic_t ipc_futex = FUTEX_INITIALIZER;
 
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);
}
 
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 */
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_async_send functions */
static inline async_call_t *ipc_prepare_async(void *private, ipc_async_callback_t callback)
{
async_call_t *call;
 
call = malloc(sizeof(*call));
if (!call) {
if (callback)
callback(private, ENOMEM, NULL);
return NULL;
}
call->callback = callback;
call->private = private;
 
return call;
}
 
/** Epilogue of ipc_async_send functions */
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);
free(call);
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->ptid = psthread_get_id();
psthread_schedule_next_adv(PS_TO_MANAGER);
/* Async futex unlocked by previous call */
} else {
call->ptid = 0;
futex_up(&async_futex);
}
return;
}
call->u.callid = callid;
/* Add call to list of dispatched calls */
list_append(&call->list, &dispatched_calls);
futex_up(&ipc_futex);
}
 
/** Send asynchronous message
*
* - if fatal error, call callback handler with proper error code
* - if message cannot be temporarily sent, add to queue
*/
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);
}
 
/** Send asynchronous message
*
* - if fatal error, call callback handler with proper error code
* - if message cannot be temporarily sent, add to queue
*/
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);
}
 
 
/** Send a fast answer to a received call.
*
* 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 ID 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);
}
 
/** Send a full answer to a received call.
*
* @param callid ID of the call being answered.
* @param call Call data. 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 queed calls from 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->ptid)
psthread_add_ready(call->ptid);
if (callid == IPC_CALLRET_FATAL) {
if (call->callback)
call->callback(call->private, ENOENT, NULL);
free(call);
} 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 received answer
*
* TODO: Make it use hash table
*
* @param callid Callid (with first bit set) of the answered call
*/
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);
free(call);
return;
}
}
futex_up(&ipc_futex);
/* We may get here after async_msg, which doesn't register any callback */
}
 
 
/** One cycle of ipc wait for call call
*
* - dispatch ASYNC reoutines in the background
* @param call Space where the message is stored
* @param usec Timeout in microseconds
* @param flags Flags passed to SYS_IPC_WAIT (blocking, nonblocking)
* @return Callid of the answer.
*/
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.
*
* - dispatch ASYNC reoutines in the background
*
* @param call Space where the message is stored
* @param usec Timeout in microseconds.
* @return Callid 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.
*
* - dispatch ASYNC reoutines in the background
*
* @param call Space where the message is stored
* @return Callid 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
*
* @return 0 - OK, error code
*/
int ipc_connect_to_me(int phoneid, int arg1, int arg2, ipcarg_t *phone)
{
return ipc_call_sync_3(phoneid, IPC_M_CONNECT_TO_ME, arg1,
arg2, 0, 0, 0, phone);
}
 
/** Ask through phone for a new connection to some service
*
* @return new phoneid - OK, 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 specified phone */
int ipc_hangup(int phoneid)
{
return __SYSCALL1(SYS_IPC_HANGUP, phoneid);
}
 
int ipc_register_irq(int irq, irq_code_t *ucode)
{
return __SYSCALL2(SYS_IPC_REGISTER_IRQ, irq, (sysarg_t) ucode);
}
 
int ipc_unregister_irq(int irq)
{
return __SYSCALL1(SYS_IPC_UNREGISTER_IRQ, irq);
}
 
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);
}
 
 
 
/** @}
*/