WebSVN – HelenOS – Diff – /trunk/uspace/srv/vfs/vfs_register.c


/*
 * Copyright (c) 2008 Jakub Jermar
 * 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 fs
 * @{
 */
 
/**
 * @file vfs_register.c
 * @brief
 */
 
#include <ipc/ipc.h>
#include <ipc/services.h>
#include <async.h>
#include <fibril.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <bool.h>
#include <fibril_sync.h>
#include <adt/list.h>
#include <as.h>
#include <assert.h>
#include <atomic.h>
#include "vfs.h"
 
FIBRIL_MUTEX_INITIALIZE(fs_head_lock);
link_t fs_head;
 
atomic_t fs_handle_next = {
    .count = 1
};
 
/** Verify the VFS info structure.
 *
 * @param info      Info structure to be verified.
 *
 * @return      Non-zero if the info structure is sane, zero otherwise.
 */
static bool vfs_info_sane(vfs_info_t *info)
{
    int i;
 
    /*
     * Check if the name is non-empty and is composed solely of ASCII
     * characters [a-z]+[a-z0-9_-]*.
     */
    if (!islower(info->name[0])) {
        dprintf("The name doesn't start with a lowercase character.\n");
        return false;
    }
    for (i = 1; i < FS_NAME_MAXLEN; i++) {
        if (!(islower(info->name[i]) || isdigit(info->name[i])) &&
            (info->name[i] != '-') && (info->name[i] != '_')) {
            if (info->name[i] == '\0') {
                break;
            } else {
                dprintf("The name contains illegal "
                    "characters.\n");
                return false;
            }
        }
    }
    /*
     * This check is not redundant. It ensures that the name is
     * NULL-terminated, even if FS_NAME_MAXLEN characters are used.
     */
    if (info->name[i] != '\0') {
        dprintf("The name is not properly NULL-terminated.\n");
        return false;
    }
   
    return true;
}
 
/** VFS_REGISTER protocol function.
 *
 * @param rid       Hash of the call with the request.
 * @param request   Call structure with the request.
 */
void vfs_register(ipc_callid_t rid, ipc_call_t *request)
{
    ipc_callid_t callid;
    ipc_call_t call;
    int rc;
    size_t size;
 
    dprintf("Processing VFS_REGISTER request received from %p.\n",
        request->in_phone_hash);
 
    /*
     * The first call has to be IPC_M_DATA_SEND in which we receive the
     * VFS info structure from the client FS.
     */
    if (!ipc_data_write_receive(&callid, &size)) {
        /*
         * The client doesn't obey the same protocol as we do.
         */
        dprintf("Receiving of VFS info failed.\n");
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
   
    dprintf("VFS info received, size = %d\n", size);
   
    /*
     * We know the size of the VFS info structure. See if the client
     * understands this easy concept too.
     */
    if (size != sizeof(vfs_info_t)) {
        /*
         * The client is sending us something, which cannot be
         * the info structure.
         */
        dprintf("Received VFS info has bad size.\n");
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
 
    /*
     * Allocate and initialize a buffer for the fs_info structure.
     */
    fs_info_t *fs_info;
    fs_info = (fs_info_t *) malloc(sizeof(fs_info_t));
    if (!fs_info) {
        dprintf("Could not allocate memory for FS info.\n");
        ipc_answer_0(callid, ENOMEM);
        ipc_answer_0(rid, ENOMEM);
        return;
    }
    link_initialize(&fs_info->fs_link);
    fibril_mutex_initialize(&fs_info->phone_lock);
       
    rc = ipc_data_write_finalize(callid, &fs_info->vfs_info, size);
    if (rc != EOK) {
        dprintf("Failed to deliver the VFS info into our AS, rc=%d.\n",
            rc);
        free(fs_info);
        ipc_answer_0(callid, rc);
        ipc_answer_0(rid, rc);
        return;
    }
 
    dprintf("VFS info delivered.\n");
       
    if (!vfs_info_sane(&fs_info->vfs_info)) {
        free(fs_info);
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
       
    fibril_mutex_lock(&fs_head_lock);
 
    /*
     * Check for duplicit registrations.
     */
    if (fs_name_to_handle(fs_info->vfs_info.name, false)) {
        /*
         * We already register a fs like this.
         */
        dprintf("FS is already registered.\n");
        fibril_mutex_unlock(&fs_head_lock);
        free(fs_info);
        ipc_answer_0(callid, EEXISTS);
        ipc_answer_0(rid, EEXISTS);
        return;
    }
 
    /*
     * Add fs_info to the list of registered FS's.
     */
    dprintf("Inserting FS into the list of registered file systems.\n");
    list_append(&fs_info->fs_link, &fs_head);
   
    /*
     * Now we want the client to send us the IPC_M_CONNECT_TO_ME call so
     * that a callback connection is created and we have a phone through
     * which to forward VFS requests to it.
     */
    callid = async_get_call(&call);
    if (IPC_GET_METHOD(call) != IPC_M_CONNECT_TO_ME) {
        dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
        list_remove(&fs_info->fs_link);
        fibril_mutex_unlock(&fs_head_lock);
        free(fs_info);
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
    fs_info->phone = IPC_GET_ARG5(call);
    ipc_answer_0(callid, EOK);
 
    dprintf("Callback connection to FS created.\n");
 
    /*
     * The client will want us to send him the address space area with PLB.
     */
 
    if (!ipc_share_in_receive(&callid, &size)) {
        dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
        list_remove(&fs_info->fs_link);
        fibril_mutex_unlock(&fs_head_lock);
        ipc_hangup(fs_info->phone);
        free(fs_info);
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
   
    /*
     * We can only send the client address space area PLB_SIZE bytes long.
     */
    if (size != PLB_SIZE) {
        dprintf("Client suggests wrong size of PFB, size = %d\n", size);
        list_remove(&fs_info->fs_link);
        fibril_mutex_unlock(&fs_head_lock);
        ipc_hangup(fs_info->phone);
        free(fs_info);
        ipc_answer_0(callid, EINVAL);
        ipc_answer_0(rid, EINVAL);
        return;
    }
 
    /*
     * Commit to read-only sharing the PLB with the client.
     */
    (void) ipc_share_in_finalize(callid, plb,
        AS_AREA_READ | AS_AREA_CACHEABLE);
 
    dprintf("Sharing PLB.\n");
 
    /*
     * That was it. The FS has been registered.
     * In reply to the VFS_REGISTER request, we assign the client file
     * system a global file system handle.
     */
    fs_info->fs_handle = (fs_handle_t) atomic_postinc(&fs_handle_next);
    ipc_answer_1(rid, EOK, (ipcarg_t) fs_info->fs_handle);
   
    pending_new_fs = true;
    fibril_condvar_signal(&pending_cv);
    fibril_mutex_unlock(&fs_head_lock);
   
    dprintf("\"%.*s\" filesystem successfully registered, handle=%d.\n",
        FS_NAME_MAXLEN, fs_info->vfs_info.name, fs_info->fs_handle);
}
 
/** For a given file system handle, implement policy for allocating a phone.
 *
 * @param handle    File system handle.
 *
 * @return      Phone over which a multi-call request can be safely
 *          sent. Return 0 if no phone was found.
 */
int vfs_grab_phone(fs_handle_t handle)
{
    int phone;
 
    /*
     * For now, we don't try to be very clever and very fast.  We simply
     * lookup the phone in the fs_head list and duplicate it.  The duplicate
     * phone will be returned to the client and the client will use it for
 
     * communication.  In the future, we should cache the connections so
     * that they do not have to be reestablished over and over again.
     */
    fibril_mutex_lock(&fs_head_lock);
    link_t *cur;
    fs_info_t *fs;
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
        fs = list_get_instance(cur, fs_info_t, fs_link);
        if (fs->fs_handle == handle) {
            fibril_mutex_unlock(&fs_head_lock);
            fibril_mutex_lock(&fs->phone_lock);
            phone = ipc_connect_me_to(fs->phone, 0, 0, 0);
            fibril_mutex_unlock(&fs->phone_lock);
 
            assert(phone > 0);
            return phone;
        }
    }
    fibril_mutex_unlock(&fs_head_lock);
    return 0;
}
 
/** Tell VFS that the phone is not needed anymore.
 *
 * @param phone     Phone to FS task.
 */
void vfs_release_phone(int phone)
{
 
 
 
 
    /* TODO: implement connection caching */
 
    ipc_hangup(phone);
 
 
 
 
 
 
 
 
 
 
 
 
}
 
/** Convert file system name to its handle.
 *
 * @param name      File system name.
 * @param lock      If true, the function will lock and unlock the
 *          fs_head_lock.
 *
 * @return      File system handle or zero if file system not found.
 */
fs_handle_t fs_name_to_handle(char *name, bool lock)
{
    int handle = 0;
   
    if (lock)
        fibril_mutex_lock(&fs_head_lock);
    link_t *cur;
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
        fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);
        if (str_cmp(fs->vfs_info.name, name) == 0) {
            handle = fs->fs_handle;
            break;
        }
    }
    if (lock)
        fibril_mutex_unlock(&fs_head_lock);
    return handle;
}
 
/**
 * @}
 */
 

Rev 4539	Rev 4551
1	/*	1	/*
2	* Copyright (c) 2008 Jakub Jermar	2	* Copyright (c) 2008 Jakub Jermar
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	/** @addtogroup fs	29	/** @addtogroup fs
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file vfs_register.c	34	* @file vfs_register.c
35	* @brief	35	* @brief
36	*/	36	*/
37		37
38	#include <ipc/ipc.h>	38	#include <ipc/ipc.h>
39	#include <ipc/services.h>	39	#include <ipc/services.h>
40	#include <async.h>	40	#include <async.h>
41	#include <fibril.h>	41	#include <fibril.h>
42	#include <errno.h>	42	#include <errno.h>
43	#include <stdio.h>	43	#include <stdio.h>
44	#include <stdlib.h>	44	#include <stdlib.h>
45	#include <string.h>	45	#include <string.h>
46	#include <ctype.h>	46	#include <ctype.h>
47	#include <bool.h>	47	#include <bool.h>
48	#include <fibril_sync.h>	48	#include <fibril_sync.h>
49	#include <adt/list.h>	49	#include <adt/list.h>
50	#include <as.h>	50	#include <as.h>
51	#include <assert.h>	51	#include <assert.h>
52	#include <atomic.h>	52	#include <atomic.h>
53	#include "vfs.h"	53	#include "vfs.h"
54		54
55	FIBRIL_MUTEX_INITIALIZE(fs_head_lock);	55	FIBRIL_MUTEX_INITIALIZE(fs_head_lock);
56	link_t fs_head;	56	link_t fs_head;
57		57
58	atomic_t fs_handle_next = {	58	atomic_t fs_handle_next = {
59	.count = 1	59	.count = 1
60	};	60	};
61		61
62	/** Verify the VFS info structure.	62	/** Verify the VFS info structure.
63	*	63	*
64	* @param info Info structure to be verified.	64	* @param info Info structure to be verified.
65	*	65	*
66	* @return Non-zero if the info structure is sane, zero otherwise.	66	* @return Non-zero if the info structure is sane, zero otherwise.
67	*/	67	*/
68	static bool vfs_info_sane(vfs_info_t *info)	68	static bool vfs_info_sane(vfs_info_t *info)
69	{	69	{
70	int i;	70	int i;
71		71
72	/*	72	/*
73	* Check if the name is non-empty and is composed solely of ASCII	73	* Check if the name is non-empty and is composed solely of ASCII
74	* characters [a-z]+[a-z0-9_-]*.	74	* characters [a-z]+[a-z0-9_-]*.
75	*/	75	*/
76	if (!islower(info->name[0])) {	76	if (!islower(info->name[0])) {
77	dprintf("The name doesn't start with a lowercase character.\n");	77	dprintf("The name doesn't start with a lowercase character.\n");
78	return false;	78	return false;
79	}	79	}
80	for (i = 1; i < FS_NAME_MAXLEN; i++) {	80	for (i = 1; i < FS_NAME_MAXLEN; i++) {
81	if (!(islower(info->name[i]) \|\| isdigit(info->name[i])) &&	81	if (!(islower(info->name[i]) \|\| isdigit(info->name[i])) &&
82	(info->name[i] != '-') && (info->name[i] != '_')) {	82	(info->name[i] != '-') && (info->name[i] != '_')) {
83	if (info->name[i] == '\0') {	83	if (info->name[i] == '\0') {
84	break;	84	break;
85	} else {	85	} else {
86	dprintf("The name contains illegal "	86	dprintf("The name contains illegal "
87	"characters.\n");	87	"characters.\n");
88	return false;	88	return false;
89	}	89	}
90	}	90	}
91	}	91	}
92	/*	92	/*
93	* This check is not redundant. It ensures that the name is	93	* This check is not redundant. It ensures that the name is
94	* NULL-terminated, even if FS_NAME_MAXLEN characters are used.	94	* NULL-terminated, even if FS_NAME_MAXLEN characters are used.
95	*/	95	*/
96	if (info->name[i] != '\0') {	96	if (info->name[i] != '\0') {
97	dprintf("The name is not properly NULL-terminated.\n");	97	dprintf("The name is not properly NULL-terminated.\n");
98	return false;	98	return false;
99	}	99	}
100		100
101	return true;	101	return true;
102	}	102	}
103		103
104	/** VFS_REGISTER protocol function.	104	/** VFS_REGISTER protocol function.
105	*	105	*
106	* @param rid Hash of the call with the request.	106	* @param rid Hash of the call with the request.
107	* @param request Call structure with the request.	107	* @param request Call structure with the request.
108	*/	108	*/
109	void vfs_register(ipc_callid_t rid, ipc_call_t *request)	109	void vfs_register(ipc_callid_t rid, ipc_call_t *request)
110	{	110	{
111	ipc_callid_t callid;	111	ipc_callid_t callid;
112	ipc_call_t call;	112	ipc_call_t call;
113	int rc;	113	int rc;
114	size_t size;	114	size_t size;
115		115
116	dprintf("Processing VFS_REGISTER request received from %p.\n",	116	dprintf("Processing VFS_REGISTER request received from %p.\n",
117	request->in_phone_hash);	117	request->in_phone_hash);
118		118
119	/*	119	/*
120	* The first call has to be IPC_M_DATA_SEND in which we receive the	120	* The first call has to be IPC_M_DATA_SEND in which we receive the
121	* VFS info structure from the client FS.	121	* VFS info structure from the client FS.
122	*/	122	*/
123	if (!ipc_data_write_receive(&callid, &size)) {	123	if (!ipc_data_write_receive(&callid, &size)) {
124	/*	124	/*
125	* The client doesn't obey the same protocol as we do.	125	* The client doesn't obey the same protocol as we do.
126	*/	126	*/
127	dprintf("Receiving of VFS info failed.\n");	127	dprintf("Receiving of VFS info failed.\n");
128	ipc_answer_0(callid, EINVAL);	128	ipc_answer_0(callid, EINVAL);
129	ipc_answer_0(rid, EINVAL);	129	ipc_answer_0(rid, EINVAL);
130	return;	130	return;
131	}	131	}
132		132
133	dprintf("VFS info received, size = %d\n", size);	133	dprintf("VFS info received, size = %d\n", size);
134		134
135	/*	135	/*
136	* We know the size of the VFS info structure. See if the client	136	* We know the size of the VFS info structure. See if the client
137	* understands this easy concept too.	137	* understands this easy concept too.
138	*/	138	*/
139	if (size != sizeof(vfs_info_t)) {	139	if (size != sizeof(vfs_info_t)) {
140	/*	140	/*
141	* The client is sending us something, which cannot be	141	* The client is sending us something, which cannot be
142	* the info structure.	142	* the info structure.
143	*/	143	*/
144	dprintf("Received VFS info has bad size.\n");	144	dprintf("Received VFS info has bad size.\n");
145	ipc_answer_0(callid, EINVAL);	145	ipc_answer_0(callid, EINVAL);
146	ipc_answer_0(rid, EINVAL);	146	ipc_answer_0(rid, EINVAL);
147	return;	147	return;
148	}	148	}
149		149
150	/*	150	/*
151	* Allocate and initialize a buffer for the fs_info structure.	151	* Allocate and initialize a buffer for the fs_info structure.
152	*/	152	*/
153	fs_info_t *fs_info;	153	fs_info_t *fs_info;
154	fs_info = (fs_info_t *) malloc(sizeof(fs_info_t));	154	fs_info = (fs_info_t *) malloc(sizeof(fs_info_t));
155	if (!fs_info) {	155	if (!fs_info) {
156	dprintf("Could not allocate memory for FS info.\n");	156	dprintf("Could not allocate memory for FS info.\n");
157	ipc_answer_0(callid, ENOMEM);	157	ipc_answer_0(callid, ENOMEM);
158	ipc_answer_0(rid, ENOMEM);	158	ipc_answer_0(rid, ENOMEM);
159	return;	159	return;
160	}	160	}
161	link_initialize(&fs_info->fs_link);	161	link_initialize(&fs_info->fs_link);
162	fibril_mutex_initialize(&fs_info->phone_lock);	162	fibril_mutex_initialize(&fs_info->phone_lock);
163		163
164	rc = ipc_data_write_finalize(callid, &fs_info->vfs_info, size);	164	rc = ipc_data_write_finalize(callid, &fs_info->vfs_info, size);
165	if (rc != EOK) {	165	if (rc != EOK) {
166	dprintf("Failed to deliver the VFS info into our AS, rc=%d.\n",	166	dprintf("Failed to deliver the VFS info into our AS, rc=%d.\n",
167	rc);	167	rc);
168	free(fs_info);	168	free(fs_info);
169	ipc_answer_0(callid, rc);	169	ipc_answer_0(callid, rc);
170	ipc_answer_0(rid, rc);	170	ipc_answer_0(rid, rc);
171	return;	171	return;
172	}	172	}
173		173
174	dprintf("VFS info delivered.\n");	174	dprintf("VFS info delivered.\n");
175		175
176	if (!vfs_info_sane(&fs_info->vfs_info)) {	176	if (!vfs_info_sane(&fs_info->vfs_info)) {
177	free(fs_info);	177	free(fs_info);
178	ipc_answer_0(callid, EINVAL);	178	ipc_answer_0(callid, EINVAL);
179	ipc_answer_0(rid, EINVAL);	179	ipc_answer_0(rid, EINVAL);
180	return;	180	return;
181	}	181	}
182		182
183	fibril_mutex_lock(&fs_head_lock);	183	fibril_mutex_lock(&fs_head_lock);
184		184
185	/*	185	/*
186	* Check for duplicit registrations.	186	* Check for duplicit registrations.
187	*/	187	*/
188	if (fs_name_to_handle(fs_info->vfs_info.name, false)) {	188	if (fs_name_to_handle(fs_info->vfs_info.name, false)) {
189	/*	189	/*
190	* We already register a fs like this.	190	* We already register a fs like this.
191	*/	191	*/
192	dprintf("FS is already registered.\n");	192	dprintf("FS is already registered.\n");
193	fibril_mutex_unlock(&fs_head_lock);	193	fibril_mutex_unlock(&fs_head_lock);
194	free(fs_info);	194	free(fs_info);
195	ipc_answer_0(callid, EEXISTS);	195	ipc_answer_0(callid, EEXISTS);
196	ipc_answer_0(rid, EEXISTS);	196	ipc_answer_0(rid, EEXISTS);
197	return;	197	return;
198	}	198	}
199		199
200	/*	200	/*
201	* Add fs_info to the list of registered FS's.	201	* Add fs_info to the list of registered FS's.
202	*/	202	*/
203	dprintf("Inserting FS into the list of registered file systems.\n");	203	dprintf("Inserting FS into the list of registered file systems.\n");
204	list_append(&fs_info->fs_link, &fs_head);	204	list_append(&fs_info->fs_link, &fs_head);
205		205
206	/*	206	/*
207	* Now we want the client to send us the IPC_M_CONNECT_TO_ME call so	207	* Now we want the client to send us the IPC_M_CONNECT_TO_ME call so
208	* that a callback connection is created and we have a phone through	208	* that a callback connection is created and we have a phone through
209	* which to forward VFS requests to it.	209	* which to forward VFS requests to it.
210	*/	210	*/
211	callid = async_get_call(&call);	211	callid = async_get_call(&call);
212	if (IPC_GET_METHOD(call) != IPC_M_CONNECT_TO_ME) {	212	if (IPC_GET_METHOD(call) != IPC_M_CONNECT_TO_ME) {
213	dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));	213	dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
214	list_remove(&fs_info->fs_link);	214	list_remove(&fs_info->fs_link);
215	fibril_mutex_unlock(&fs_head_lock);	215	fibril_mutex_unlock(&fs_head_lock);
216	free(fs_info);	216	free(fs_info);
217	ipc_answer_0(callid, EINVAL);	217	ipc_answer_0(callid, EINVAL);
218	ipc_answer_0(rid, EINVAL);	218	ipc_answer_0(rid, EINVAL);
219	return;	219	return;
220	}	220	}
221	fs_info->phone = IPC_GET_ARG5(call);	221	fs_info->phone = IPC_GET_ARG5(call);
222	ipc_answer_0(callid, EOK);	222	ipc_answer_0(callid, EOK);
223		223
224	dprintf("Callback connection to FS created.\n");	224	dprintf("Callback connection to FS created.\n");
225		225
226	/*	226	/*
227	* The client will want us to send him the address space area with PLB.	227	* The client will want us to send him the address space area with PLB.
228	*/	228	*/
229		229
230	if (!ipc_share_in_receive(&callid, &size)) {	230	if (!ipc_share_in_receive(&callid, &size)) {
231	dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));	231	dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
232	list_remove(&fs_info->fs_link);	232	list_remove(&fs_info->fs_link);
233	fibril_mutex_unlock(&fs_head_lock);	233	fibril_mutex_unlock(&fs_head_lock);
234	ipc_hangup(fs_info->phone);	234	ipc_hangup(fs_info->phone);
235	free(fs_info);	235	free(fs_info);
236	ipc_answer_0(callid, EINVAL);	236	ipc_answer_0(callid, EINVAL);
237	ipc_answer_0(rid, EINVAL);	237	ipc_answer_0(rid, EINVAL);
238	return;	238	return;
239	}	239	}
240		240
241	/*	241	/*
242	* We can only send the client address space area PLB_SIZE bytes long.	242	* We can only send the client address space area PLB_SIZE bytes long.
243	*/	243	*/
244	if (size != PLB_SIZE) {	244	if (size != PLB_SIZE) {
245	dprintf("Client suggests wrong size of PFB, size = %d\n", size);	245	dprintf("Client suggests wrong size of PFB, size = %d\n", size);
246	list_remove(&fs_info->fs_link);	246	list_remove(&fs_info->fs_link);
247	fibril_mutex_unlock(&fs_head_lock);	247	fibril_mutex_unlock(&fs_head_lock);
248	ipc_hangup(fs_info->phone);	248	ipc_hangup(fs_info->phone);
249	free(fs_info);	249	free(fs_info);
250	ipc_answer_0(callid, EINVAL);	250	ipc_answer_0(callid, EINVAL);
251	ipc_answer_0(rid, EINVAL);	251	ipc_answer_0(rid, EINVAL);
252	return;	252	return;
253	}	253	}
254		254
255	/*	255	/*
256	* Commit to read-only sharing the PLB with the client.	256	* Commit to read-only sharing the PLB with the client.
257	*/	257	*/
258	(void) ipc_share_in_finalize(callid, plb,	258	(void) ipc_share_in_finalize(callid, plb,
259	AS_AREA_READ \| AS_AREA_CACHEABLE);	259	AS_AREA_READ \| AS_AREA_CACHEABLE);
260		260
261	dprintf("Sharing PLB.\n");	261	dprintf("Sharing PLB.\n");
262		262
263	/*	263	/*
264	* That was it. The FS has been registered.	264	* That was it. The FS has been registered.
265	* In reply to the VFS_REGISTER request, we assign the client file	265	* In reply to the VFS_REGISTER request, we assign the client file
266	* system a global file system handle.	266	* system a global file system handle.
267	*/	267	*/
268	fs_info->fs_handle = (fs_handle_t) atomic_postinc(&fs_handle_next);	268	fs_info->fs_handle = (fs_handle_t) atomic_postinc(&fs_handle_next);
269	ipc_answer_1(rid, EOK, (ipcarg_t) fs_info->fs_handle);	269	ipc_answer_1(rid, EOK, (ipcarg_t) fs_info->fs_handle);
270		270
271	pending_new_fs = true;	271	pending_new_fs = true;
272	fibril_condvar_signal(&pending_cv);	272	fibril_condvar_signal(&pending_cv);
273	fibril_mutex_unlock(&fs_head_lock);	273	fibril_mutex_unlock(&fs_head_lock);
274		274
275	dprintf("\"%.*s\" filesystem successfully registered, handle=%d.\n",	275	dprintf("\"%.*s\" filesystem successfully registered, handle=%d.\n",
276	FS_NAME_MAXLEN, fs_info->vfs_info.name, fs_info->fs_handle);	276	FS_NAME_MAXLEN, fs_info->vfs_info.name, fs_info->fs_handle);
277	}	277	}
278		278
279	/** For a given file system handle, implement policy for allocating a phone.	279	/** For a given file system handle, implement policy for allocating a phone.
280	*	280	*
281	* @param handle File system handle.	281	* @param handle File system handle.
282	*	282	*
283	* @return Phone over which a multi-call request can be safely	283	* @return Phone over which a multi-call request can be safely
284	* sent. Return 0 if no phone was found.	284	* sent. Return 0 if no phone was found.
285	*/	285	*/
286	int vfs_grab_phone(fs_handle_t handle)	286	int vfs_grab_phone(fs_handle_t handle)
287	{	287	{
-		288	int phone;
-		289
288	/*	290	/*
289	* For now, we don't try to be very clever and very fast.	291	* For now, we don't try to be very clever and very fast. We simply
290	* We simply lookup the phone in the fs_head list. We currently don't	292	* lookup the phone in the fs_head list and duplicate it. The duplicate
291	* open any additional phones (even though that itself would be pretty	293	* phone will be returned to the client and the client will use it for
292	* straightforward; housekeeping multiple open phones to a FS task would	-
293	* be more demanding). Instead, we simply take the respective	294	* communication. In the future, we should cache the connections so
294	* phone_futex and keep it until vfs_release_phone().	295	* that they do not have to be reestablished over and over again.
295	*/	296	*/
296	fibril_mutex_lock(&fs_head_lock);	297	fibril_mutex_lock(&fs_head_lock);
297	link_t *cur;	298	link_t *cur;
298	fs_info_t *fs;	299	fs_info_t *fs;
299	for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {	300	for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
300	fs = list_get_instance(cur, fs_info_t, fs_link);	301	fs = list_get_instance(cur, fs_info_t, fs_link);
301	if (fs->fs_handle == handle) {	302	if (fs->fs_handle == handle) {
302	fibril_mutex_unlock(&fs_head_lock);	303	fibril_mutex_unlock(&fs_head_lock);
303	fibril_mutex_lock(&fs->phone_lock);	304	fibril_mutex_lock(&fs->phone_lock);
-		305	phone = ipc_connect_me_to(fs->phone, 0, 0, 0);
-		306	fibril_mutex_unlock(&fs->phone_lock);
-		307
-		308	assert(phone > 0);
304	return fs->phone;	309	return phone;
305	}	310	}
306	}	311	}
307	fibril_mutex_unlock(&fs_head_lock);	312	fibril_mutex_unlock(&fs_head_lock);
308	return 0;	313	return 0;
309	}	314	}
310		315
311	/** Tell VFS that the phone is in use for any request.	316	/** Tell VFS that the phone is not needed anymore.
312	*	317	*
313	* @param phone Phone to FS task.	318	* @param phone Phone to FS task.
314	*/	319	*/
315	void vfs_release_phone(int phone)	320	void vfs_release_phone(int phone)
316	{	321	{
317	bool found = false;	-
318		-
319	fibril_mutex_lock(&fs_head_lock);	-
320	link_t *cur;	-
321	for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {	322	/* TODO: implement connection caching */
322	fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);	-
323	if (fs->phone == phone) {	323	ipc_hangup(phone);
324	found = true;	-
325	fibril_mutex_unlock(&fs_head_lock);	-
326	fibril_mutex_unlock(&fs->phone_lock);	-
327	return;	-
328	}	-
329	}	-
330	fibril_mutex_unlock(&fs_head_lock);	-
331		-
332	/*	-
333	* Not good to get here.	-
334	*/	-
335	assert(found == true);	-
336	}	324	}
337		325
338	/** Convert file system name to its handle.	326	/** Convert file system name to its handle.
339	*	327	*
340	* @param name File system name.	328	* @param name File system name.
341	* @param lock If true, the function will lock and unlock the	329	* @param lock If true, the function will lock and unlock the
342	* fs_head_lock.	330	* fs_head_lock.
343	*	331	*
344	* @return File system handle or zero if file system not found.	332	* @return File system handle or zero if file system not found.
345	*/	333	*/
346	fs_handle_t fs_name_to_handle(char *name, bool lock)	334	fs_handle_t fs_name_to_handle(char *name, bool lock)
347	{	335	{
348	int handle = 0;	336	int handle = 0;
349		337
350	if (lock)	338	if (lock)
351	fibril_mutex_lock(&fs_head_lock);	339	fibril_mutex_lock(&fs_head_lock);
352	link_t *cur;	340	link_t *cur;
353	for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {	341	for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
354	fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);	342	fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);
355	if (str_cmp(fs->vfs_info.name, name) == 0) {	343	if (str_cmp(fs->vfs_info.name, name) == 0) {
356	handle = fs->fs_handle;	344	handle = fs->fs_handle;
357	break;	345	break;
358	}	346	}
359	}	347	}
360	if (lock)	348	if (lock)
361	fibril_mutex_unlock(&fs_head_lock);	349	fibril_mutex_unlock(&fs_head_lock);
362	return handle;	350	return handle;
363	}	351	}
364		352
365	/**	353	/**
366	* @}	354	* @}
367	*/	355	*/
368		356

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(root)/trunk/uspace/srv/vfs/vfs_register.c – Rev 4539 → 4551