WebSVN – HelenOS – Diff – /branches/network/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"
 
 
vfs_info_t tmpfs_vfs_info = {
    .name = "tmpfs",
    .ops = {
 
 
 
        [IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,
        [IPC_METHOD_TO_VFS_OP(VFS_OPEN)] = VFS_OP_DEFINED,
 
        [IPC_METHOD_TO_VFS_OP(VFS_CLOSE)] = VFS_OP_DEFINED,
        [IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,
        [IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_DEFINED,
        [IPC_METHOD_TO_VFS_OP(VFS_TRUNCATE)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_RENAME)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_OPENDIR)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_READDIR)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_CLOSEDIR)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_UNLINK)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_NULL,
    }
};
 
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_LOOKUP:
            tmpfs_lookup(callid, &call);
            break;
        case VFS_READ:
            tmpfs_read(callid, &call);
            break;
        default:
            ipc_answer_0(callid, ENOTSUP);
            break;
        }
    }
}
 
int main(int argc, char **argv)
{
    int vfs_phone;
 
    printf("TMPFS: 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("Failed to register the TMPFS file system (%d)\n", rc);
        return rc;
    }
   
    dprintf("TMPFS filesystem registered, fs_handle=%d.\n",
        tmpfs_reg.fs_handle);
 
    async_manager();
    /* not reached */
    return 0;
}
 
/**
 * @}
 */
 

Rev 2658	Rev 2690
1	/*	1	/*
2	* Copyright (c) 2006 Martin Decky	2	* Copyright (c) 2006 Martin Decky
3	* Copyright (c) 2007 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		53
54	vfs_info_t tmpfs_vfs_info = {	54	vfs_info_t tmpfs_vfs_info = {
55	.name = "tmpfs",	55	.name = "tmpfs",
56	.ops = {	56	.ops = {
57	[IPC_METHOD_TO_VFS_OP(VFS_REGISTER)] = VFS_OP_DEFINED,	-
58	[IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_DEFINED,	-
59	[IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_DEFINED,	-
60	[IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,	57	[IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,
61	[IPC_METHOD_TO_VFS_OP(VFS_OPEN)] = VFS_OP_DEFINED,	58	[IPC_METHOD_TO_VFS_OP(VFS_OPEN)] = VFS_OP_DEFINED,
62	[IPC_METHOD_TO_VFS_OP(VFS_CREATE)] = VFS_OP_DEFINED,	-
63	[IPC_METHOD_TO_VFS_OP(VFS_CLOSE)] = VFS_OP_DEFINED,	59	[IPC_METHOD_TO_VFS_OP(VFS_CLOSE)] = VFS_OP_DEFINED,
64	[IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,	60	[IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,
65	[IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_DEFINED,	61	[IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_DEFINED,
-		62	[IPC_METHOD_TO_VFS_OP(VFS_TRUNCATE)] = VFS_OP_NULL,
66	[IPC_METHOD_TO_VFS_OP(VFS_SEEK)] = VFS_OP_DEFAULT	63	[IPC_METHOD_TO_VFS_OP(VFS_RENAME)] = VFS_OP_NULL,
-		64	[IPC_METHOD_TO_VFS_OP(VFS_OPENDIR)] = VFS_OP_NULL,
-		65	[IPC_METHOD_TO_VFS_OP(VFS_READDIR)] = VFS_OP_NULL,
-		66	[IPC_METHOD_TO_VFS_OP(VFS_CLOSEDIR)] = VFS_OP_NULL,
-		67	[IPC_METHOD_TO_VFS_OP(VFS_UNLINK)] = VFS_OP_NULL,
-		68	[IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_NULL,
-		69	[IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_NULL,
67	}	70	}
68	};	71	};
69		72
70	fs_reg_t tmpfs_reg;	73	fs_reg_t tmpfs_reg;
71		74
72	/**	75	/**
73	* This connection fibril processes VFS requests from VFS.	76	* This connection fibril processes VFS requests from VFS.
74	*	77	*
75	* In order to support simultaneous VFS requests, our design is as follows.	78	* 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	79	* 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	80	* 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	81	* 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	82	* 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	83	* created, which in turn will accept the call. Thus, a new phone will be
81	* opened for VFS.	84	* opened for VFS.
82	*	85	*
83	* There are few issues with this arrangement. First, VFS can run out of	86	* 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	87	* 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	88	* 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	89	* 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	90	* 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	91	* upon each request, TMPFS might want to keep the connections open after the
89	* request has been completed.	92	* request has been completed.
90	*/	93	*/
91	static void tmpfs_connection(ipc_callid_t iid, ipc_call_t *icall)	94	static void tmpfs_connection(ipc_callid_t iid, ipc_call_t *icall)
92	{	95	{
93	if (iid) {	96	if (iid) {
94	/*	97	/*
95	* This only happens for connections opened by	98	* This only happens for connections opened by
96	* IPC_M_CONNECT_ME_TO calls as opposed to callback connections	99	* IPC_M_CONNECT_ME_TO calls as opposed to callback connections
97	* created by IPC_M_CONNECT_TO_ME.	100	* created by IPC_M_CONNECT_TO_ME.
98	*/	101	*/
99	ipc_answer_0(iid, EOK);	102	ipc_answer_0(iid, EOK);
100	}	103	}
101		104
102	dprintf("VFS-TMPFS connection established.\n");	105	dprintf("VFS-TMPFS connection established.\n");
103	while (1) {	106	while (1) {
104	ipc_callid_t callid;	107	ipc_callid_t callid;
105	ipc_call_t call;	108	ipc_call_t call;
106		109
107	callid = async_get_call(&call);	110	callid = async_get_call(&call);
108	switch (IPC_GET_METHOD(call)) {	111	switch (IPC_GET_METHOD(call)) {
109	case VFS_REGISTER:	-
110	ipc_answer_0(callid, EOK);	-
111	break;	-
112	case VFS_LOOKUP:	112	case VFS_LOOKUP:
113	tmpfs_lookup(callid, &call);	113	tmpfs_lookup(callid, &call);
114	break;	114	break;
115	case VFS_READ:	115	case VFS_READ:
116	tmpfs_read(callid, &call);	116	tmpfs_read(callid, &call);
117	break;	117	break;
118	default:	118	default:
119	ipc_answer_0(callid, ENOTSUP);	119	ipc_answer_0(callid, ENOTSUP);
120	break;	120	break;
121	}	121	}
122	}	122	}
123	}	123	}
124		124
125	int main(int argc, char **argv)	125	int main(int argc, char **argv)
126	{	126	{
127	int vfs_phone;	127	int vfs_phone;
128		128
129	printf("TMPFS: HelenOS TMPFS file system server.\n");	129	printf("TMPFS: HelenOS TMPFS file system server.\n");
130		130
131	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);	131	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
132	while (vfs_phone < EOK) {	132	while (vfs_phone < EOK) {
133	usleep(10000);	133	usleep(10000);
134	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);	134	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
135	}	135	}
136		136
137	int rc;	137	int rc;
138	rc = fs_register(vfs_phone, &tmpfs_reg, &tmpfs_vfs_info,	138	rc = fs_register(vfs_phone, &tmpfs_reg, &tmpfs_vfs_info,
139	tmpfs_connection);	139	tmpfs_connection);
140	if (rc != EOK) {	140	if (rc != EOK) {
141	printf("Failed to register the TMPFS file system (%d)\n", rc);	141	printf("Failed to register the TMPFS file system (%d)\n", rc);
142	return rc;	142	return rc;
143	}	143	}
144		144
145	dprintf("TMPFS filesystem registered, fs_handle=%d.\n",	145	dprintf("TMPFS filesystem registered, fs_handle=%d.\n",
146	tmpfs_reg.fs_handle);	146	tmpfs_reg.fs_handle);
147		147
148	async_manager();	148	async_manager();
149	/* not reached */	149	/* not reached */
150	return 0;	150	return 0;
151	}	151	}
152		152
153	/**	153	/**
154	* @}	154	* @}
155	*/	155	*/
156		156

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(root)/branches/network/uspace/srv/fs/tmpfs/tmpfs.c @ 4718 – Rev 2658 → 2690