WebSVN – HelenOS – Diff – /trunk/uspace/srv/fs/fat/fat.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    fat.c
 * @brief   FAT file system driver for HelenOS.
 */
 
#include "fat.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 fat_vfs_info = {
    .name = "fat",
    .ops = {
        [IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,
        [IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,
        [IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_TRUNCATE)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_NULL,
        [IPC_METHOD_TO_VFS_OP(VFS_MOUNTED)] = VFS_OP_DEFINED,
        [IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_NULL,
    }
};
 
fs_reg_t fat_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 FAT 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, FAT 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, FAT might want to keep the connections open after the
 * request has been completed.
 */
static void fat_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-FAT 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:
            fat_mounted(callid, &call);
            break;
        case VFS_MOUNT:
            fat_mount(callid, &call);
            break;
        case VFS_LOOKUP:
            fat_lookup(callid, &call);
            break;
        default:
            ipc_answer_0(callid, ENOTSUP);
            break;
        }
    }
}
 
int main(int argc, char **argv)
{
    int vfs_phone;
    int rc;
 
    printf("FAT: HelenOS FAT file system server.\n");
 
    rc = fat_idx_init();
    if (rc != EOK)
        goto err;
 
    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);
    }
   
 
    rc = fs_register(vfs_phone, &fat_reg, &fat_vfs_info, fat_connection);
    if (rc != EOK) {
        fat_idx_fini();
        goto err;
    }
   
    dprintf("FAT filesystem registered, fs_handle=%d.\n",
        fat_reg.fs_handle);
 
    async_manager();
    /* not reached */
    return 0;
 
err:
    printf("Failed to register the FAT file system (%d)\n", rc);
    return rc;
}
 
/**
 * @}
 */
 

Rev 2731	Rev 3110
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 fat.c	35	* @file fat.c
36	* @brief FAT file system driver for HelenOS.	36	* @brief FAT file system driver for HelenOS.
37	*/	37	*/
38		38
39	#include "fat.h"	39	#include "fat.h"
40	#include <ipc/ipc.h>	40	#include <ipc/ipc.h>
41	#include <ipc/services.h>	41	#include <ipc/services.h>
42	#include <async.h>	42	#include <async.h>
43	#include <errno.h>	43	#include <errno.h>
44	#include <unistd.h>	44	#include <unistd.h>
45	#include <stdio.h>	45	#include <stdio.h>
46	#include <libfs.h>	46	#include <libfs.h>
47	#include "../../vfs/vfs.h"	47	#include "../../vfs/vfs.h"
48		48
49		49
50	vfs_info_t fat_vfs_info = {	50	vfs_info_t fat_vfs_info = {
51	.name = "fat",	51	.name = "fat",
52	.ops = {	52	.ops = {
53	[IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,	53	[IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,
54	[IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,	54	[IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,
55	[IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_NULL,	55	[IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_NULL,
56	[IPC_METHOD_TO_VFS_OP(VFS_TRUNCATE)] = VFS_OP_NULL,	56	[IPC_METHOD_TO_VFS_OP(VFS_TRUNCATE)] = VFS_OP_NULL,
57	[IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_NULL,	57	[IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_NULL,
-		58	[IPC_METHOD_TO_VFS_OP(VFS_MOUNTED)] = VFS_OP_DEFINED,
58	[IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_NULL,	59	[IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_NULL,
59	}	60	}
60	};	61	};
61		62
62	fs_reg_t fat_reg;	63	fs_reg_t fat_reg;
63		64
64	/**	65	/**
65	* This connection fibril processes VFS requests from VFS.	66	* This connection fibril processes VFS requests from VFS.
66	*	67	*
67	* In order to support simultaneous VFS requests, our design is as follows.	68	* In order to support simultaneous VFS requests, our design is as follows.
68	* The connection fibril accepts VFS requests from VFS. If there is only one	69	* The connection fibril accepts VFS requests from VFS. If there is only one
69	* instance of the fibril, VFS will need to serialize all VFS requests it sends	70	* instance of the fibril, VFS will need to serialize all VFS requests it sends
70	* to FAT. To overcome this bottleneck, VFS can send FAT the IPC_M_CONNECT_ME_TO	71	* to FAT. To overcome this bottleneck, VFS can send FAT the IPC_M_CONNECT_ME_TO
71	* call. In that case, a new connection fibril will be created, which in turn	72	* call. In that case, a new connection fibril will be created, which in turn
72	* will accept the call. Thus, a new phone will be opened for VFS.	73	* will accept the call. Thus, a new phone will be opened for VFS.
73	*	74	*
74	* There are few issues with this arrangement. First, VFS can run out of	75	* There are few issues with this arrangement. First, VFS can run out of
75	* available phones. In that case, VFS can close some other phones or use one	76	* available phones. In that case, VFS can close some other phones or use one
76	* phone for more serialized requests. Similarily, FAT can refuse to duplicate	77	* phone for more serialized requests. Similarily, FAT can refuse to duplicate
77	* the connection. VFS should then just make use of already existing phones and	78	* the connection. VFS should then just make use of already existing phones and
78	* route its requests through them. To avoid paying the fibril creation price	79	* route its requests through them. To avoid paying the fibril creation price
79	* upon each request, FAT might want to keep the connections open after the	80	* upon each request, FAT might want to keep the connections open after the
80	* request has been completed.	81	* request has been completed.
81	*/	82	*/
82	static void fat_connection(ipc_callid_t iid, ipc_call_t *icall)	83	static void fat_connection(ipc_callid_t iid, ipc_call_t *icall)
83	{	84	{
84	if (iid) {	85	if (iid) {
85	/*	86	/*
86	* This only happens for connections opened by	87	* This only happens for connections opened by
87	* IPC_M_CONNECT_ME_TO calls as opposed to callback connections	88	* IPC_M_CONNECT_ME_TO calls as opposed to callback connections
88	* created by IPC_M_CONNECT_TO_ME.	89	* created by IPC_M_CONNECT_TO_ME.
89	*/	90	*/
90	ipc_answer_0(iid, EOK);	91	ipc_answer_0(iid, EOK);
91	}	92	}
92		93
93	dprintf("VFS-FAT connection established.\n");	94	dprintf("VFS-FAT connection established.\n");
94	while (1) {	95	while (1) {
95	ipc_callid_t callid;	96	ipc_callid_t callid;
96	ipc_call_t call;	97	ipc_call_t call;
97		98
98	callid = async_get_call(&call);	99	callid = async_get_call(&call);
99	switch (IPC_GET_METHOD(call)) {	100	switch (IPC_GET_METHOD(call)) {
-		101	case VFS_MOUNTED:
-		102	fat_mounted(callid, &call);
-		103	break;
-		104	case VFS_MOUNT:
-		105	fat_mount(callid, &call);
-		106	break;
100	case VFS_LOOKUP:	107	case VFS_LOOKUP:
101	fat_lookup(callid, &call);	108	fat_lookup(callid, &call);
102	break;	109	break;
103	default:	110	default:
104	ipc_answer_0(callid, ENOTSUP);	111	ipc_answer_0(callid, ENOTSUP);
105	break;	112	break;
106	}	113	}
107	}	114	}
108	}	115	}
109		116
110	int main(int argc, char **argv)	117	int main(int argc, char **argv)
111	{	118	{
112	int vfs_phone;	119	int vfs_phone;
-		120	int rc;
113		121
114	printf("FAT: HelenOS FAT file system server.\n");	122	printf("FAT: HelenOS FAT file system server.\n");
115		123
-		124	rc = fat_idx_init();
-		125	if (rc != EOK)
-		126	goto err;
-		127
116	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);	128	vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
117	while (vfs_phone < EOK) {	129	while (vfs_phone < EOK) {
118	usleep(10000);	130	usleep(10000);
119	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);
120	}	132	}
121		133
122	int rc;	-
123	rc = fs_register(vfs_phone, &fat_reg, &fat_vfs_info, fat_connection);	134	rc = fs_register(vfs_phone, &fat_reg, &fat_vfs_info, fat_connection);
124	if (rc != EOK) {	135	if (rc != EOK) {
125	printf("Failed to register the FAT file system (%d)\n", rc);	136	fat_idx_fini();
126	return rc;	137	goto err;
127	}	138	}
128		139
129	dprintf("FAT filesystem registered, fs_handle=%d.\n",	140	dprintf("FAT filesystem registered, fs_handle=%d.\n",
130	fat_reg.fs_handle);	141	fat_reg.fs_handle);
131		142
132	async_manager();	143	async_manager();
133	/* not reached */	144	/* not reached */
134	return 0;	145	return 0;
-		146
-		147	err:
-		148	printf("Failed to register the FAT file system (%d)\n", rc);
-		149	return rc;
135	}	150	}
136		151
137	/**	152	/**
138	* @}	153	* @}
139	*/	154	*/
140		155

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/fs/fat/fat.c – Rev 2731 → 3110