WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/ipc/ipc.c


/*
 * 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.
 */
 
/* Lock ordering
 *
 * First the answerbox, then the phone
 */
 
#include <synch/spinlock.h>
#include <synch/waitq.h>
#include <ipc/ipc.h>
#include <errno.h>
#include <mm/slab.h>
#include <arch.h>
#include <proc/task.h>
#include <memstr.h>
#include <debug.h>
 
#include <print.h>
#include <proc/thread.h>
 
/* Open channel that is assigned automatically to new tasks */
answerbox_t *ipc_phone_0 = NULL;
 
static slab_cache_t *ipc_call_slab;
 
/* Initialize new call */
static void _ipc_call_init(call_t *call)
{
    memsetb((__address)call, sizeof(*call), 0);
    call->callerbox = &TASK->answerbox;
    call->sender = TASK;
}
 
/** Allocate & initialize call structure
 *
 * The call is initialized, so that the reply will be directed
 * to TASK->answerbox
 */
call_t * ipc_call_alloc(void)
{
    call_t *call;
 
    call = slab_alloc(ipc_call_slab, 0);
    _ipc_call_init(call);
 
    return call;
}
 
/** Initialize allocated call */
void ipc_call_static_init(call_t *call)
{
    _ipc_call_init(call);
    call->flags |= IPC_CALL_STATIC_ALLOC;
}
 
/** Deallocate call stracuture */
void ipc_call_free(call_t *call)
{
    slab_free(ipc_call_slab, call);
}
 
/** Initialize answerbox structure
 */
void ipc_answerbox_init(answerbox_t *box)
{
    spinlock_initialize(&box->lock, "ipc_box_lock");
    waitq_initialize(&box->wq);
    list_initialize(&box->connected_phones);
    list_initialize(&box->calls);
    list_initialize(&box->dispatched_calls);
    list_initialize(&box->answers);
    box->task = TASK;
}
 
/** Connect phone to answerbox */
void ipc_phone_connect(phone_t *phone, answerbox_t *box)
{
    spinlock_lock(&phone->lock);
 
    ASSERT(!phone->callee);
    phone->busy = IPC_BUSY_CONNECTED;
    phone->callee = box;
 
    spinlock_lock(&box->lock);
    list_append(&phone->list, &box->connected_phones);
    spinlock_unlock(&box->lock);
 
    spinlock_unlock(&phone->lock);
}
 
/** Initialize phone structure and connect phone to naswerbox
 */
void ipc_phone_init(phone_t *phone)
{
    spinlock_initialize(&phone->lock, "phone_lock");
    phone->callee = NULL;
    phone->busy = IPC_BUSY_FREE;
    atomic_set(&phone->active_calls, 0);
}
 
/** Helper function to facilitate synchronous calls */
void ipc_call_sync(phone_t *phone, call_t *request)
{
    answerbox_t sync_box;
 
    ipc_answerbox_init(&sync_box);
 
    /* We will receive data on special box */
    request->callerbox = &sync_box;
 
    ipc_call(phone, request);
    ipc_wait_for_call(&sync_box, 0);
}
 
/** Answer message that was not dispatched and is not entered in
 * any queue
 */
static void _ipc_answer_free_call(call_t *call)
{
    answerbox_t *callerbox = call->callerbox;
 
    call->flags |= IPC_CALL_ANSWERED;
 
    spinlock_lock(&callerbox->lock);
    list_append(&call->list, &callerbox->answers);
    spinlock_unlock(&callerbox->lock);
    waitq_wakeup(&callerbox->wq, 0);
}
 
/** Answer message, that is in callee queue
 *
 * @param box Answerbox that is answering the message
 * @param call Modified request that is being sent back
 */
void ipc_answer(answerbox_t *box, call_t *call)
{
    /* Remove from active box */
    spinlock_lock(&box->lock);
    list_remove(&call->list);
    spinlock_unlock(&box->lock);
    /* Send back answer */
    _ipc_answer_free_call(call);
}
 
/** Simulate sending back a message
 *
 * Most errors are better handled by forming a normal backward
 * message and sending it as a normal answer.
 */
void ipc_backsend_err(phone_t *phone, call_t *call, __native err)
{
    call->data.phone = phone;
    atomic_inc(&phone->active_calls);
    if (phone->busy == IPC_BUSY_CONNECTED)
        IPC_SET_RETVAL(call->data, EHANGUP);
    else
        IPC_SET_RETVAL(call->data, ENOENT);
 
    _ipc_answer_free_call(call);
}
 
/* Unsafe unchecking ipc_call */
static void _ipc_call(phone_t *phone, answerbox_t *box, call_t *call)
{
    if (! (call->flags & IPC_CALL_FORWARDED)) {
        atomic_inc(&phone->active_calls);
        call->data.phone = phone;
    }
 
    spinlock_lock(&box->lock);
    list_append(&call->list, &box->calls);
    spinlock_unlock(&box->lock);
    waitq_wakeup(&box->wq, 0);
}
 
/** Send a asynchronous request using phone to answerbox
 *
 * @param phone Phone connected to answerbox
 * @param request Request to be sent
 */
int ipc_call(phone_t *phone, call_t *call)
{
    answerbox_t *box;
 
    spinlock_lock(&phone->lock);
 
    box = phone->callee;
    if (!box) {
        /* Trying to send over disconnected phone */
        spinlock_unlock(&phone->lock);
        if (call->flags & IPC_CALL_FORWARDED) {
            IPC_SET_RETVAL(call->data, EFORWARD);
            _ipc_answer_free_call(call);
        } else { /* Simulate sending back a message */
            if (phone->busy == IPC_BUSY_CONNECTED)
                ipc_backsend_err(phone, call, EHANGUP);
            else
                ipc_backsend_err(phone, call, ENOENT);
        }
 
        return ENOENT;
    }
    _ipc_call(phone, box, call);
   
    spinlock_unlock(&phone->lock);
    return 0;
}
 
/** Disconnect phone from answerbox
 *
 * It is allowed to call disconnect on already disconnected phone
 *
 * @return 0 - phone disconnected, -1 - the phone was already disconnected
 */
int ipc_phone_hangup(phone_t *phone)
{
    answerbox_t *box;
    call_t *call;
   
    spinlock_lock(&phone->lock);
    box = phone->callee;
    if (!box) {
        if (phone->busy == IPC_BUSY_CONNECTING) {
            spinlock_unlock(&phone->lock);
            return -1;
        }
        /* Already disconnected phone */
        phone->busy = IPC_BUSY_FREE;
        spinlock_unlock(&phone->lock);
        return 0;
    }
 
    spinlock_lock(&box->lock);
    list_remove(&phone->list);
    phone->callee = NULL;
    spinlock_unlock(&box->lock);
 
    call = ipc_call_alloc();
    IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);
    call->flags |= IPC_CALL_DISCARD_ANSWER;
    _ipc_call(phone, box, call);
 
    phone->busy = IPC_BUSY_FREE;
 
    spinlock_unlock(&phone->lock);
 
    return 0;
}
 
/** Forwards call from one answerbox to a new one
 *
 * @param request Request to be forwarded
 * @param newbox Target answerbox
 * @param oldbox Old answerbox
 * @return 0 on forward ok, error code, if there was error
 *
 * - the return value serves only as an information for the forwarder,
 *   the original caller is notified automatically with EFORWARD
 */
int ipc_forward(call_t *call, phone_t *newphone, answerbox_t *oldbox)
{
    spinlock_lock(&oldbox->lock);
    list_remove(&call->list);
    spinlock_unlock(&oldbox->lock);
 
    return ipc_call(newphone, call);
}
 
 
/** Wait for phone call
 *
 * @return Recived message address
 * - to distinguish between call and answer, look at call->flags
 */
call_t * ipc_wait_for_call(answerbox_t *box, int flags)
{
    call_t *request;
 
restart:      
    if (flags & IPC_WAIT_NONBLOCKING) {
        if (waitq_sleep_timeout(&box->wq,0,1) == ESYNCH_WOULD_BLOCK)
            return NULL;
    } else
        waitq_sleep(&box->wq);
   
    spinlock_lock(&box->lock);
    if (!list_empty(&box->answers)) {
        /* Handle asynchronous answers */
        request = list_get_instance(box->answers.next, call_t, list);
        list_remove(&request->list);
        atomic_dec(&request->data.phone->active_calls);
    } else if (!list_empty(&box->calls)) {
        /* Handle requests */
        request = list_get_instance(box->calls.next, call_t, list);
        list_remove(&request->list);
        /* Append request to dispatch queue */
        list_append(&request->list, &box->dispatched_calls);
    } else {
        /* This can happen regularly after ipc_cleanup, remove
         * the warning in the future when the IPC is
         * more debugged */
        printf("WARNING: Spurious IPC wakeup.\n");
        spinlock_unlock(&box->lock);
        goto restart;
    }
    spinlock_unlock(&box->lock);
    return request;
}
 
/** Initilize ipc subsystem */
void ipc_init(void)
{
    ipc_call_slab = slab_cache_create("ipc_call",
                      sizeof(call_t),
                      0,
                      NULL, NULL, 0);
}
 
/** Answer all calls from list with EHANGUP msg */
static void ipc_cleanup_call_list(link_t *lst)
{
    call_t *call;
 
    while (!list_empty(lst)) {
        call = list_get_instance(lst->next, call_t, list);
        list_remove(&call->list);
 
        IPC_SET_RETVAL(call->data, EHANGUP);
        _ipc_answer_free_call(call);
    }
}
 
/** Cleans up all IPC communication of the given task
 *
 *
 */
void ipc_cleanup(task_t *task)
{
    int i;
    call_t *call;
    phone_t *phone;
   
    /* Disconnect all our phones ('ipc_phone_hangup') */
    for (i=0;i < IPC_MAX_PHONES; i++)
        ipc_phone_hangup(&task->phones[i]);
 
    /* Disconnect all phones connected to our answerbox */
restart_phones:
    spinlock_lock(&task->answerbox.lock);
    while (!list_empty(&task->answerbox.connected_phones)) {
        phone = list_get_instance(task->answerbox.connected_phones.next,
                      phone_t,
                      list);
        if (! spinlock_trylock(&phone->lock)) {
            spinlock_unlock(&task->answerbox.lock);
            goto restart_phones;
        }
       
        /* Disconnect phone */
        phone->callee = NULL;
        list_remove(&phone->list);
 
        spinlock_unlock(&phone->lock);
    }
 
    /* Answer all messages in 'calls' and 'dispatched_calls' queues */
    spinlock_lock(&task->answerbox.lock);
    ipc_cleanup_call_list(&task->answerbox.dispatched_calls);
    ipc_cleanup_call_list(&task->answerbox.calls);
    spinlock_unlock(&task->answerbox.lock);
   
    /* Wait for all async answers to arrive */
    while (atomic_get(&task->active_calls)) {
        call = ipc_wait_for_call(&task->answerbox, 0);
        ASSERT(call->flags & IPC_CALL_ANSWERED);
        ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
       
        atomic_dec(&task->active_calls);
        ipc_call_free(call);
    }
}
 

Rev 1090	Rev 1141
1	/*	1	/*
2	* Copyright (C) 2006 Ondrej Palkovsky	2	* Copyright (C) 2006 Ondrej Palkovsky
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/* Lock ordering	29	/* Lock ordering
30	*	30	*
31	* First the answerbox, then the phone	31	* First the answerbox, then the phone
32	*/	32	*/
33		33
34	#include <synch/spinlock.h>	34	#include <synch/spinlock.h>
35	#include <synch/waitq.h>	35	#include <synch/waitq.h>
36	#include <ipc/ipc.h>	36	#include <ipc/ipc.h>
37	#include <errno.h>	37	#include <errno.h>
38	#include <mm/slab.h>	38	#include <mm/slab.h>
39	#include <arch.h>	39	#include <arch.h>
40	#include <proc/task.h>	40	#include <proc/task.h>
41	#include <memstr.h>	41	#include <memstr.h>
42	#include <debug.h>	42	#include <debug.h>
43		43
44	#include <print.h>	44	#include <print.h>
45	#include <proc/thread.h>	45	#include <proc/thread.h>
46		46
47	/* Open channel that is assigned automatically to new tasks */	47	/* Open channel that is assigned automatically to new tasks */
48	answerbox_t *ipc_phone_0 = NULL;	48	answerbox_t *ipc_phone_0 = NULL;
49		49
50	static slab_cache_t *ipc_call_slab;	50	static slab_cache_t *ipc_call_slab;
51		51
52	/* Initialize new call */	52	/* Initialize new call */
53	static void _ipc_call_init(call_t *call)	53	static void _ipc_call_init(call_t *call)
54	{	54	{
55	memsetb((__address)call, sizeof(*call), 0);	55	memsetb((__address)call, sizeof(*call), 0);
56	call->callerbox = &TASK->answerbox;	56	call->callerbox = &TASK->answerbox;
57	call->sender = TASK;	57	call->sender = TASK;
58	}	58	}
59		59
60	/** Allocate & initialize call structure	60	/** Allocate & initialize call structure
61	*	61	*
62	* The call is initialized, so that the reply will be directed	62	* The call is initialized, so that the reply will be directed
63	* to TASK->answerbox	63	* to TASK->answerbox
64	*/	64	*/
65	call_t * ipc_call_alloc(void)	65	call_t * ipc_call_alloc(void)
66	{	66	{
67	call_t *call;	67	call_t *call;
68		68
69	call = slab_alloc(ipc_call_slab, 0);	69	call = slab_alloc(ipc_call_slab, 0);
70	_ipc_call_init(call);	70	_ipc_call_init(call);
71		71
72	return call;	72	return call;
73	}	73	}
74		74
75	/** Initialize allocated call */	75	/** Initialize allocated call */
76	void ipc_call_static_init(call_t *call)	76	void ipc_call_static_init(call_t *call)
77	{	77	{
78	_ipc_call_init(call);	78	_ipc_call_init(call);
79	call->flags \|= IPC_CALL_STATIC_ALLOC;	79	call->flags \|= IPC_CALL_STATIC_ALLOC;
80	}	80	}
81		81
82	/** Deallocate call stracuture */	82	/** Deallocate call stracuture */
83	void ipc_call_free(call_t *call)	83	void ipc_call_free(call_t *call)
84	{	84	{
85	slab_free(ipc_call_slab, call);	85	slab_free(ipc_call_slab, call);
86	}	86	}
87		87
88	/** Initialize answerbox structure	88	/** Initialize answerbox structure
89	*/	89	*/
90	void ipc_answerbox_init(answerbox_t *box)	90	void ipc_answerbox_init(answerbox_t *box)
91	{	91	{
92	spinlock_initialize(&box->lock, "ipc_box_lock");	92	spinlock_initialize(&box->lock, "ipc_box_lock");
93	waitq_initialize(&box->wq);	93	waitq_initialize(&box->wq);
94	list_initialize(&box->connected_phones);	94	list_initialize(&box->connected_phones);
95	list_initialize(&box->calls);	95	list_initialize(&box->calls);
96	list_initialize(&box->dispatched_calls);	96	list_initialize(&box->dispatched_calls);
97	list_initialize(&box->answers);	97	list_initialize(&box->answers);
98	box->task = TASK;	98	box->task = TASK;
99	}	99	}
100		100
101	/** Connect phone to answerbox */	101	/** Connect phone to answerbox */
102	void ipc_phone_connect(phone_t phone, answerbox_t box)	102	void ipc_phone_connect(phone_t phone, answerbox_t box)
103	{	103	{
104	spinlock_lock(&phone->lock);	104	spinlock_lock(&phone->lock);
105		105
106	ASSERT(!phone->callee);	106	ASSERT(!phone->callee);
107	phone->busy = IPC_BUSY_CONNECTED;	107	phone->busy = IPC_BUSY_CONNECTED;
108	phone->callee = box;	108	phone->callee = box;
109		109
110	spinlock_lock(&box->lock);	110	spinlock_lock(&box->lock);
111	list_append(&phone->list, &box->connected_phones);	111	list_append(&phone->list, &box->connected_phones);
112	spinlock_unlock(&box->lock);	112	spinlock_unlock(&box->lock);
113		113
114	spinlock_unlock(&phone->lock);	114	spinlock_unlock(&phone->lock);
115	}	115	}
116		116
117	/** Initialize phone structure and connect phone to naswerbox	117	/** Initialize phone structure and connect phone to naswerbox
118	*/	118	*/
119	void ipc_phone_init(phone_t *phone)	119	void ipc_phone_init(phone_t *phone)
120	{	120	{
121	spinlock_initialize(&phone->lock, "phone_lock");	121	spinlock_initialize(&phone->lock, "phone_lock");
122	phone->callee = NULL;	122	phone->callee = NULL;
123	phone->busy = IPC_BUSY_FREE;	123	phone->busy = IPC_BUSY_FREE;
124	atomic_set(&phone->active_calls, 0);	124	atomic_set(&phone->active_calls, 0);
125	}	125	}
126		126
127	/** Helper function to facilitate synchronous calls */	127	/** Helper function to facilitate synchronous calls */
128	void ipc_call_sync(phone_t phone, call_t request)	128	void ipc_call_sync(phone_t phone, call_t request)
129	{	129	{
130	answerbox_t sync_box;	130	answerbox_t sync_box;
131		131
132	ipc_answerbox_init(&sync_box);	132	ipc_answerbox_init(&sync_box);
133		133
134	/* We will receive data on special box */	134	/* We will receive data on special box */
135	request->callerbox = &sync_box;	135	request->callerbox = &sync_box;
136		136
137	ipc_call(phone, request);	137	ipc_call(phone, request);
138	ipc_wait_for_call(&sync_box, 0);	138	ipc_wait_for_call(&sync_box, 0);
139	}	139	}
140		140
141	/** Answer message that was not dispatched and is not entered in	141	/** Answer message that was not dispatched and is not entered in
142	* any queue	142	* any queue
143	*/	143	*/
144	static void _ipc_answer_free_call(call_t *call)	144	static void _ipc_answer_free_call(call_t *call)
145	{	145	{
146	answerbox_t *callerbox = call->callerbox;	146	answerbox_t *callerbox = call->callerbox;
147		147
148	call->flags \|= IPC_CALL_ANSWERED;	148	call->flags \|= IPC_CALL_ANSWERED;
149		149
150	spinlock_lock(&callerbox->lock);	150	spinlock_lock(&callerbox->lock);
151	list_append(&call->list, &callerbox->answers);	151	list_append(&call->list, &callerbox->answers);
152	spinlock_unlock(&callerbox->lock);	152	spinlock_unlock(&callerbox->lock);
153	waitq_wakeup(&callerbox->wq, 0);	153	waitq_wakeup(&callerbox->wq, 0);
154	}	154	}
155		155
156	/** Answer message, that is in callee queue	156	/** Answer message, that is in callee queue
157	*	157	*
158	* @param box Answerbox that is answering the message	158	* @param box Answerbox that is answering the message
159	* @param call Modified request that is being sent back	159	* @param call Modified request that is being sent back
160	*/	160	*/
161	void ipc_answer(answerbox_t box, call_t call)	161	void ipc_answer(answerbox_t box, call_t call)
162	{	162	{
163	/* Remove from active box */	163	/* Remove from active box */
164	spinlock_lock(&box->lock);	164	spinlock_lock(&box->lock);
165	list_remove(&call->list);	165	list_remove(&call->list);
166	spinlock_unlock(&box->lock);	166	spinlock_unlock(&box->lock);
167	/* Send back answer */	167	/* Send back answer */
168	_ipc_answer_free_call(call);	168	_ipc_answer_free_call(call);
169	}	169	}
170		170
171	/** Simulate sending back a message	171	/** Simulate sending back a message
172	*	172	*
173	* Most errors are better handled by forming a normal backward	173	* Most errors are better handled by forming a normal backward
174	* message and sending it as a normal answer.	174	* message and sending it as a normal answer.
175	*/	175	*/
176	void ipc_backsend_err(phone_t phone, call_t call, __native err)	176	void ipc_backsend_err(phone_t phone, call_t call, __native err)
177	{	177	{
178	call->data.phone = phone;	178	call->data.phone = phone;
179	atomic_inc(&phone->active_calls);	179	atomic_inc(&phone->active_calls);
180	if (phone->busy == IPC_BUSY_CONNECTED)	180	if (phone->busy == IPC_BUSY_CONNECTED)
181	IPC_SET_RETVAL(call->data, EHANGUP);	181	IPC_SET_RETVAL(call->data, EHANGUP);
182	else	182	else
183	IPC_SET_RETVAL(call->data, ENOENT);	183	IPC_SET_RETVAL(call->data, ENOENT);
184		184
185	_ipc_answer_free_call(call);	185	_ipc_answer_free_call(call);
186	}	186	}
187		187
188	/* Unsafe unchecking ipc_call */	188	/* Unsafe unchecking ipc_call */
189	static void _ipc_call(phone_t phone, answerbox_t box, call_t *call)	189	static void _ipc_call(phone_t phone, answerbox_t box, call_t *call)
190	{	190	{
191	if (! (call->flags & IPC_CALL_FORWARDED)) {	191	if (! (call->flags & IPC_CALL_FORWARDED)) {
192	atomic_inc(&phone->active_calls);	192	atomic_inc(&phone->active_calls);
193	call->data.phone = phone;	193	call->data.phone = phone;
194	}	194	}
195		195
196	spinlock_lock(&box->lock);	196	spinlock_lock(&box->lock);
197	list_append(&call->list, &box->calls);	197	list_append(&call->list, &box->calls);
198	spinlock_unlock(&box->lock);	198	spinlock_unlock(&box->lock);
199	waitq_wakeup(&box->wq, 0);	199	waitq_wakeup(&box->wq, 0);
200	}	200	}
201		201
202	/** Send a asynchronous request using phone to answerbox	202	/** Send a asynchronous request using phone to answerbox
203	*	203	*
204	* @param phone Phone connected to answerbox	204	* @param phone Phone connected to answerbox
205	* @param request Request to be sent	205	* @param request Request to be sent
206	*/	206	*/
207	int ipc_call(phone_t phone, call_t call)	207	int ipc_call(phone_t phone, call_t call)
208	{	208	{
209	answerbox_t *box;	209	answerbox_t *box;
210		210
211	spinlock_lock(&phone->lock);	211	spinlock_lock(&phone->lock);
212		212
213	box = phone->callee;	213	box = phone->callee;
214	if (!box) {	214	if (!box) {
215	/* Trying to send over disconnected phone */	215	/* Trying to send over disconnected phone */
216	spinlock_unlock(&phone->lock);	216	spinlock_unlock(&phone->lock);
217	if (call->flags & IPC_CALL_FORWARDED) {	217	if (call->flags & IPC_CALL_FORWARDED) {
218	IPC_SET_RETVAL(call->data, EFORWARD);	218	IPC_SET_RETVAL(call->data, EFORWARD);
219	_ipc_answer_free_call(call);	219	_ipc_answer_free_call(call);
220	} else { /* Simulate sending back a message */	220	} else { /* Simulate sending back a message */
221	if (phone->busy == IPC_BUSY_CONNECTED)	221	if (phone->busy == IPC_BUSY_CONNECTED)
222	ipc_backsend_err(phone, call, EHANGUP);	222	ipc_backsend_err(phone, call, EHANGUP);
223	else	223	else
224	ipc_backsend_err(phone, call, ENOENT);	224	ipc_backsend_err(phone, call, ENOENT);
225	}	225	}
226		226
227	return ENOENT;	227	return ENOENT;
228	}	228	}
229	_ipc_call(phone, box, call);	229	_ipc_call(phone, box, call);
230		230
231	spinlock_unlock(&phone->lock);	231	spinlock_unlock(&phone->lock);
232	return 0;	232	return 0;
233	}	233	}
234		234
235	/** Disconnect phone from answerbox	235	/** Disconnect phone from answerbox
236	*	236	*
237	* It is allowed to call disconnect on already disconnected phone	237	* It is allowed to call disconnect on already disconnected phone
238	*	238	*
239	* @return 0 - phone disconnected, -1 - the phone was already disconnected	239	* @return 0 - phone disconnected, -1 - the phone was already disconnected
240	*/	240	*/
241	int ipc_phone_hangup(phone_t *phone)	241	int ipc_phone_hangup(phone_t *phone)
242	{	242	{
243	answerbox_t *box;	243	answerbox_t *box;
244	call_t *call;	244	call_t *call;
245		245
246	spinlock_lock(&phone->lock);	246	spinlock_lock(&phone->lock);
247	box = phone->callee;	247	box = phone->callee;
248	if (!box) {	248	if (!box) {
249	if (phone->busy == IPC_BUSY_CONNECTING) {	249	if (phone->busy == IPC_BUSY_CONNECTING) {
250	spinlock_unlock(&phone->lock);	250	spinlock_unlock(&phone->lock);
251	return -1;	251	return -1;
252	}	252	}
253	/* Already disconnected phone */	253	/* Already disconnected phone */
254	phone->busy = IPC_BUSY_FREE;	254	phone->busy = IPC_BUSY_FREE;
255	spinlock_unlock(&phone->lock);	255	spinlock_unlock(&phone->lock);
256	return 0;	256	return 0;
257	}	257	}
258		258
259	spinlock_lock(&box->lock);	259	spinlock_lock(&box->lock);
260	list_remove(&phone->list);	260	list_remove(&phone->list);
261	phone->callee = NULL;	261	phone->callee = NULL;
262	spinlock_unlock(&box->lock);	262	spinlock_unlock(&box->lock);
263		263
264	call = ipc_call_alloc();	264	call = ipc_call_alloc();
265	IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);	265	IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);
266	call->flags \|= IPC_CALL_DISCARD_ANSWER;	266	call->flags \|= IPC_CALL_DISCARD_ANSWER;
267	_ipc_call(phone, box, call);	267	_ipc_call(phone, box, call);
268		268
269	phone->busy = IPC_BUSY_FREE;	269	phone->busy = IPC_BUSY_FREE;
270		270
271	spinlock_unlock(&phone->lock);	271	spinlock_unlock(&phone->lock);
272		272
273	return 0;	273	return 0;
274	}	274	}
275		275
276	/** Forwards call from one answerbox to a new one	276	/** Forwards call from one answerbox to a new one
277	*	277	*
278	* @param request Request to be forwarded	278	* @param request Request to be forwarded
279	* @param newbox Target answerbox	279	* @param newbox Target answerbox
280	* @param oldbox Old answerbox	280	* @param oldbox Old answerbox
281	* @return 0 on forward ok, error code, if there was error	281	* @return 0 on forward ok, error code, if there was error
282	*	282	*
283	* - the return value serves only as an information for the forwarder,	283	* - the return value serves only as an information for the forwarder,
284	* the original caller is notified automatically with EFORWARD	284	* the original caller is notified automatically with EFORWARD
285	*/	285	*/
286	int ipc_forward(call_t call, phone_t newphone, answerbox_t *oldbox)	286	int ipc_forward(call_t call, phone_t newphone, answerbox_t *oldbox)
287	{	287	{
288	spinlock_lock(&oldbox->lock);	288	spinlock_lock(&oldbox->lock);
289	list_remove(&call->list);	289	list_remove(&call->list);
290	spinlock_unlock(&oldbox->lock);	290	spinlock_unlock(&oldbox->lock);
291		291
292	return ipc_call(newphone, call);	292	return ipc_call(newphone, call);
293	}	293	}
294		294
295		295
296	/** Wait for phone call	296	/** Wait for phone call
297	*	297	*
298	* @return Recived message address	298	* @return Recived message address
299	* - to distinguish between call and answer, look at call->flags	299	* - to distinguish between call and answer, look at call->flags
300	*/	300	*/
301	call_t * ipc_wait_for_call(answerbox_t *box, int flags)	301	call_t * ipc_wait_for_call(answerbox_t *box, int flags)
302	{	302	{
303	call_t *request;	303	call_t *request;
304		304
305	restart:	305	restart:
306	if (flags & IPC_WAIT_NONBLOCKING) {	306	if (flags & IPC_WAIT_NONBLOCKING) {
307	if (waitq_sleep_timeout(&box->wq,0,1) == ESYNCH_WOULD_BLOCK)	307	if (waitq_sleep_timeout(&box->wq,0,1) == ESYNCH_WOULD_BLOCK)
308	return NULL;	308	return NULL;
309	} else	309	} else
310	waitq_sleep(&box->wq);	310	waitq_sleep(&box->wq);
311		311
312	spinlock_lock(&box->lock);	312	spinlock_lock(&box->lock);
313	if (!list_empty(&box->answers)) {	313	if (!list_empty(&box->answers)) {
314	/* Handle asynchronous answers */	314	/* Handle asynchronous answers */
315	request = list_get_instance(box->answers.next, call_t, list);	315	request = list_get_instance(box->answers.next, call_t, list);
316	list_remove(&request->list);	316	list_remove(&request->list);
317	atomic_dec(&request->data.phone->active_calls);	317	atomic_dec(&request->data.phone->active_calls);
318	} else if (!list_empty(&box->calls)) {	318	} else if (!list_empty(&box->calls)) {
319	/* Handle requests */	319	/* Handle requests */
320	request = list_get_instance(box->calls.next, call_t, list);	320	request = list_get_instance(box->calls.next, call_t, list);
321	list_remove(&request->list);	321	list_remove(&request->list);
322	/* Append request to dispatch queue */	322	/* Append request to dispatch queue */
323	list_append(&request->list, &box->dispatched_calls);	323	list_append(&request->list, &box->dispatched_calls);
324	} else {	324	} else {
-		325	/* This can happen regularly after ipc_cleanup, remove
-		326	* the warning in the future when the IPC is
-		327	* more debugged */
325	printf("WARNING: Spurious IPC wakeup.\n");	328	printf("WARNING: Spurious IPC wakeup.\n");
326	spinlock_unlock(&box->lock);	329	spinlock_unlock(&box->lock);
327	goto restart;	330	goto restart;
328	}	331	}
329	spinlock_unlock(&box->lock);	332	spinlock_unlock(&box->lock);
330	return request;	333	return request;
331	}	334	}
332		335
333	/** Initilize ipc subsystem */	336	/** Initilize ipc subsystem */
334	void ipc_init(void)	337	void ipc_init(void)
335	{	338	{
336	ipc_call_slab = slab_cache_create("ipc_call",	339	ipc_call_slab = slab_cache_create("ipc_call",
337	sizeof(call_t),	340	sizeof(call_t),
338	0,	341	0,
339	NULL, NULL, 0);	342	NULL, NULL, 0);
340	}	343	}
341		344
-		345	/** Answer all calls from list with EHANGUP msg */
-		346	static void ipc_cleanup_call_list(link_t *lst)
-		347	{
-		348	call_t *call;
-		349
-		350	while (!list_empty(lst)) {
-		351	call = list_get_instance(lst->next, call_t, list);
-		352	list_remove(&call->list);
-		353
-		354	IPC_SET_RETVAL(call->data, EHANGUP);
-		355	_ipc_answer_free_call(call);
-		356	}
-		357	}
-		358
342	/** Cleans up all IPC communication of the given task	359	/** Cleans up all IPC communication of the given task
343	*	360	*
344	*	361	*
345	*/	362	*/
346	void ipc_cleanup(task_t *task)	363	void ipc_cleanup(task_t *task)
347	{	364	{
348	int i;	365	int i;
-		366	call_t *call;
-		367	phone_t *phone;
349		368
350	/* Disconnect all our phones ('ipc_phone_hangup') */	369	/* Disconnect all our phones ('ipc_phone_hangup') */
351	for (i=0;i < IPC_MAX_PHONES; i++)	370	for (i=0;i < IPC_MAX_PHONES; i++)
352	ipc_phone_hangup(&task->phones[i]);	371	ipc_phone_hangup(&task->phones[i]);
353		372
354	/* Disconnect all phones connected to answerbox */	373	/* Disconnect all phones connected to our answerbox */
-		374	restart_phones:
-		375	spinlock_lock(&task->answerbox.lock);
-		376	while (!list_empty(&task->answerbox.connected_phones)) {
-		377	phone = list_get_instance(task->answerbox.connected_phones.next,
-		378	phone_t,
-		379	list);
-		380	if (! spinlock_trylock(&phone->lock)) {
-		381	spinlock_unlock(&task->answerbox.lock);
-		382	goto restart_phones;
-		383	}
-		384
-		385	/* Disconnect phone */
-		386	phone->callee = NULL;
-		387	list_remove(&phone->list);
-		388
-		389	spinlock_unlock(&phone->lock);
-		390	}
355		391
356	/* Answer all messages in 'calls' and 'dispatched_calls' queues */	392	/* Answer all messages in 'calls' and 'dispatched_calls' queues */
-		393	spinlock_lock(&task->answerbox.lock);
-		394	ipc_cleanup_call_list(&task->answerbox.dispatched_calls);
-		395	ipc_cleanup_call_list(&task->answerbox.calls);
-		396	spinlock_unlock(&task->answerbox.lock);
357		397
358	/* Wait for all async answers to arrive */	398	/* Wait for all async answers to arrive */
-		399	while (atomic_get(&task->active_calls)) {
-		400	call = ipc_wait_for_call(&task->answerbox, 0);
-		401	ASSERT(call->flags & IPC_CALL_ANSWERED);
-		402	ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
-		403
-		404	atomic_dec(&task->active_calls);
-		405	ipc_call_free(call);
-		406	}
359	}	407	}
360		408

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/ipc/ipc.c – Rev 1090 → 1141