WebSVN – HelenOS – Diff – /branches/dynload/uspace/srv/fs/tmpfs/tmpfs.c


/*
 * Copyright (c) 2006 Martin Decky
 * 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    tmpfs.c
 * @brief   File system driver for in-memory file system.
 *
 * Every instance of tmpfs exists purely in memory and has neither a disk layout
 * nor any permanent storage (e.g. disk blocks). With each system reboot, data
 * stored in a tmpfs file system is lost.
 */
 
#include "tmpfs.h"
#include <ipc/ipc.h>
#include <ipc/services.h>
#include <async.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <libfs.h>
#include "../../vfs/vfs.h"
 
#define NAME "tmpfs"
 
 
vfs_info_t tmpfs_vfs_info = {
    .name = "tmpfs",
 
 
 
 
 
 
 
 
 
 
};
 
fs_reg_t tmpfs_reg;
 
/**
 * This connection fibril processes VFS requests from VFS.
 *
 * In order to support simultaneous VFS requests, our design is as follows.
 * The connection fibril accepts VFS requests from VFS. If there is only one
 * instance of the fibril, VFS will need to serialize all VFS requests it sends
 * to FAT. To overcome this bottleneck, VFS can send TMPFS the
 * IPC_M_CONNECT_ME_TO call. In that case, a new connection fibril will be
 * created, which in turn will accept the call. Thus, a new phone will be
 * opened for VFS.
 *
 * There are few issues with this arrangement. First, VFS can run out of
 * available phones. In that case, VFS can close some other phones or use one
 * phone for more serialized requests. Similarily, TMPFS can refuse to duplicate
 * the connection. VFS should then just make use of already existing phones and
 * route its requests through them. To avoid paying the fibril creation price
 * upon each request, TMPFS might want to keep the connections open after the
 * request has been completed.
 */
static void tmpfs_connection(ipc_callid_t iid, ipc_call_t *icall)
{
    if (iid) {
        /*
         * This only happens for connections opened by
         * IPC_M_CONNECT_ME_TO calls as opposed to callback connections
         * created by IPC_M_CONNECT_TO_ME.
         */
        ipc_answer_0(iid, EOK);
    }
   
    dprintf("VFS-TMPFS connection established.\n");
    while (1) {
        ipc_callid_t callid;
        ipc_call_t call;
   
        callid = async_get_call(&call);
        switch  (IPC_GET_METHOD(call)) {
        case VFS_MOUNTED:
            tmpfs_mounted(callid, &call);
            break;
        case VFS_MOUNT:
            tmpfs_mount(callid, &call);
            break;
        case VFS_LOOKUP:
            tmpfs_lookup(callid, &call);
            break;
        case VFS_READ:
            tmpfs_read(callid, &call);
            break;
        case VFS_WRITE:
            tmpfs_write(callid, &call);
            break;
        case VFS_TRUNCATE:
            tmpfs_truncate(callid, &call);
            break;
        case VFS_DESTROY:
            tmpfs_destroy(callid, &call);
            break;
        default:
            ipc_answer_0(callid, ENOTSUP);
            break;
        }
    }
}
 
int main(int argc, char **argv)
{
    int vfs_phone;
 
    printf(NAME ": HelenOS TMPFS file system server\n");
 
    vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
    while (vfs_phone < EOK) {
        usleep(10000);
        vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
    }
   
    int rc;
    rc = fs_register(vfs_phone, &tmpfs_reg, &tmpfs_vfs_info,
        tmpfs_connection);
    if (rc != EOK) {
        printf(NAME ": Failed to register file system (%d)\n", rc);
        return rc;
    }
   
    printf(NAME ": Accepting connections\n");
    async_manager();
    /* not reached */
    return 0;
}
 
/**
 * @}
 */
 

Rev 3153	Rev 4341
1	/*	1	/*
2	* Copyright (c) 2006 Martin Decky	2	* Copyright (c) 2006 Martin Decky
3	* Copyright (c) 2008 Jakub Jermar	3	* Copyright (c) 2008 Jakub Jermar
4	* All rights reserved.	4	* All rights reserved.
5	*	5	*
6	* Redistribution and use in source and binary forms, with or without	6	* Redistribution and use in source and binary forms, with or without
7	* modification, are permitted provided that the following conditions	7	* modification, are permitted provided that the following conditions
8	* are met:	8	* are met:
9	*	9	*
10	* - Redistributions of source code must retain the above copyright	10	* - Redistributions of source code must retain the above copyright
11	* notice, this list of conditions and the following disclaimer.	11	* notice, this list of conditions and the following disclaimer.
12	* - Redistributions in binary form must reproduce the above copyright	12	* - Redistributions in binary form must reproduce the above copyright
13	* notice, this list of conditions and the following disclaimer in the	13	* notice, this list of conditions and the following disclaimer in the
14	* documentation and/or other materials provided with the distribution.	14	* documentation and/or other materials provided with the distribution.
15	* - The name of the author may not be used to endorse or promote products	15	* - The name of the author may not be used to endorse or promote products
16	* derived from this software without specific prior written permission.	16	* derived from this software without specific prior written permission.
17	*	17	*
18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28	*/	28	*/
29		29
30	/** @addtogroup fs	30	/** @addtogroup fs
31	* @{	31	* @{
32	*/	32	*/
33		33
34	/**	34	/**
35	* @file tmpfs.c	35	* @file tmpfs.c
36	* @brief File system driver for in-memory file system.	36	* @brief File system driver for in-memory file system.
37	*	37	*
38	* Every instance of tmpfs exists purely in memory and has neither a disk layout	38	* Every instance of tmpfs exists purely in memory and has neither a disk layout
39	* nor any permanent storage (e.g. disk blocks). With each system reboot, data	39	* nor any permanent storage (e.g. disk blocks). With each system reboot, data
40	* stored in a tmpfs file system is lost.	40	* stored in a tmpfs file system is lost.
41	*/	41	*/
42		42
43	#include "tmpfs.h"	43	#include "tmpfs.h"
44	#include <ipc/ipc.h>	44	#include <ipc/ipc.h>
45	#include <ipc/services.h>	45	#include <ipc/services.h>
46	#include <async.h>	46	#include <async.h>
47	#include <errno.h>	47	#include <errno.h>
48	#include <unistd.h>	48	#include <unistd.h>
49	#include <stdio.h>	49	#include <stdio.h>
50	#include <libfs.h>	50	#include <libfs.h>
51	#include "../../vfs/vfs.h"	51	#include "../../vfs/vfs.h"
52		52
53	#define NAME "tmpfs"	53	#define NAME "tmpfs"
54		54
55		55
56	vfs_info_t tmpfs_vfs_info = {	56	vfs_info_t tmpfs_vfs_info = {
57	.name = "tmpfs",	57	.name = "tmpfs",
58	.ops = {	-
59	[IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,	-
60	[IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,	-
61	[IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_DEFINED,	-
62	[IPC_METHOD_TO_VFS_OP(VFS_TRUNCATE)] = VFS_OP_DEFINED,	-
63	[IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_DEFINED,	-
64	[IPC_METHOD_TO_VFS_OP(VFS_MOUNTED)] = VFS_OP_DEFINED,	-
65	[IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_NULL,	-
66	[IPC_METHOD_TO_VFS_OP(VFS_DESTROY)] = VFS_OP_DEFINED,	-
67	}	-
68	};	58	};
69		59
70	fs_reg_t tmpfs_reg;	60	fs_reg_t tmpfs_reg;
71		61
72	/**	62	/**
73	* This connection fibril processes VFS requests from VFS.	63	* This connection fibril processes VFS requests from VFS.
74	*	64	*
75	* In order to support simultaneous VFS requests, our design is as follows.	65	* In order to support simultaneous VFS requests, our design is as follows.
76	* The connection fibril accepts VFS requests from VFS. If there is only one	66	* The connection fibril accepts VFS requests from VFS. If there is only one
77	* instance of the fibril, VFS will need to serialize all VFS requests it sends	67	* instance of the fibril, VFS will need to serialize all VFS requests it sends
78	* to FAT. To overcome this bottleneck, VFS can send TMPFS the	68	* to FAT. To overcome this bottleneck, VFS can send TMPFS the
79	* IPC_M_CONNECT_ME_TO call. In that case, a new connection fibril will be	69	* IPC_M_CONNECT_ME_TO call. In that case, a new connection fibril will be
80	* created, which in turn will accept the call. Thus, a new phone will be	70	* created, which in turn will accept the call. Thus, a new phone will be
81	* opened for VFS.	71	* opened for VFS.
82	*	72	*
83	* There are few issues with this arrangement. First, VFS can run out of	73	* There are few issues with this arrangement. First, VFS can run out of
84	* available phones. In that case, VFS can close some other phones or use one	74	* available phones. In that case, VFS can close some other phones or use one
85	* phone for more serialized requests. Similarily, TMPFS can refuse to duplicate	75	* phone for more serialized requests. Similarily, TMPFS can refuse to duplicate
86	* the connection. VFS should then just make use of already existing phones and	76	* the connection. VFS should then just make use of already existing phones and
87	* route its requests through them. To avoid paying the fibril creation price	77	* route its requests through them. To avoid paying the fibril creation price
88	* upon each request, TMPFS might want to keep the connections open after the	78	* upon each request, TMPFS might want to keep the connections open after the
89	* request has been completed.	79	* request has been completed.
90	*/	80	*/
91	static void tmpfs_connection(ipc_callid_t iid, ipc_call_t *icall)	81	static void tmpfs_connection(ipc_callid_t iid, ipc_call_t *icall)
92	{	82	{
93	if (iid) {	83	if (iid) {
94	/*	84	/*
95	* This only happens for connections opened by	85	* This only happens for connections opened by
96	* IPC_M_CONNECT_ME_TO calls as opposed to callback connections	86	* IPC_M_CONNECT_ME_TO calls as opposed to callback connections
97	* created by IPC_M_CONNECT_TO_ME.	87	* created by IPC_M_CONNECT_TO_ME.
98	*/	88	*/
99	ipc_answer_0(iid, EOK);	89	ipc_answer_0(iid, EOK);
100	}	90	}
101		91
102	dprintf("VFS-TMPFS connection established.\n");	92	dprintf("VFS-TMPFS connection established.\n");
103	while (1) {	93	while (1) {
104	ipc_callid_t callid;	94	ipc_callid_t callid;
105	ipc_call_t call;	95	ipc_call_t call;
106		96
107	callid = async_get_call(&call);	97	callid = async_get_call(&call);
108	switch (IPC_GET_METHOD(call)) {	98	switch (IPC_GET_METHOD(call)) {
109	case VFS_MOUNTED:	99	case VFS_MOUNTED:
110	tmpfs_mounted(callid, &call);	100	tmpfs_mounted(callid, &call);
111	break;	101	break;
112	case VFS_MOUNT:	102	case VFS_MOUNT:
113	tmpfs_mount(callid, &call);	103	tmpfs_mount(callid, &call);
114	break;	104	break;
115	case VFS_LOOKUP:	105	case VFS_LOOKUP:
116	tmpfs_lookup(callid, &call);	106	tmpfs_lookup(callid, &call);
117	break;	107	break;
118	case VFS_READ:	108	case VFS_READ:
119	tmpfs_read(callid, &call);	109	tmpfs_read(callid, &call);
120	break;	110	break;
121	case VFS_WRITE:	111	case VFS_WRITE:
122	tmpfs_write(callid, &call);	112	tmpfs_write(callid, &call);
123	break;	113	break;
124	case VFS_TRUNCATE:	114	case VFS_TRUNCATE:
125	tmpfs_truncate(callid, &call);	115	tmpfs_truncate(callid, &call);
126	break;	116	break;
127	case VFS_DESTROY:	117	case VFS_DESTROY:
128	tmpfs_destroy(callid, &call);	118	tmpfs_destroy(callid, &call);
129	break;	119	break;
130	default:	120	default:
131	ipc_answer_0(callid, ENOTSUP);	121	ipc_answer_0(callid, ENOTSUP);
132	break;	122	break;
133	}	123	}
134	}	124	}
135	}	125	}
136		126
137	int main(int argc, char **argv)	127	int main(int argc, char **argv)
138	{	128	{
139	int vfs_phone;	129	int vfs_phone;
140		130
141	printf(NAME ": HelenOS TMPFS file system server\n");	131	printf(NAME ": HelenOS TMPFS file system server\n");
142		132
143	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);	133	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
144	while (vfs_phone < EOK) {	134	while (vfs_phone < EOK) {
145	usleep(10000);	135	usleep(10000);
146	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);	136	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
147	}	137	}
148		138
149	int rc;	139	int rc;
150	rc = fs_register(vfs_phone, &tmpfs_reg, &tmpfs_vfs_info,	140	rc = fs_register(vfs_phone, &tmpfs_reg, &tmpfs_vfs_info,
151	tmpfs_connection);	141	tmpfs_connection);
152	if (rc != EOK) {	142	if (rc != EOK) {
153	printf(NAME ": Failed to register file system (%d)\n", rc);	143	printf(NAME ": Failed to register file system (%d)\n", rc);
154	return rc;	144	return rc;
155	}	145	}
156		146
157	printf(NAME ": Accepting connections\n");	147	printf(NAME ": Accepting connections\n");
158	async_manager();	148	async_manager();
159	/* not reached */	149	/* not reached */
160	return 0;	150	return 0;
161	}	151	}
162		152
163	/**	153	/**
164	* @}	154	* @}
165	*/	155	*/
166		156

Subversion Repositories HelenOS

(root)/branches/dynload/uspace/srv/fs/tmpfs/tmpfs.c @ 4345 – Rev 3153 → 4341