WebSVN – HelenOS – Diff – /trunk/uspace/srv/vfs/vfs.h


/*
 * Copyright (c) 2007 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
 * @{
 */
 
#ifndef VFS_VFS_H_
#define VFS_VFS_H_
 
#include <ipc/ipc.h>
#include <libadt/list.h>
#include <atomic.h>
#include <sys/types.h>
#include <bool.h>
 
#define dprintf(...)    printf(__VA_ARGS__)
 
#define VFS_FIRST   IPC_FIRST_USER_METHOD
 
#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)   
 
typedef enum {
    VFS_REGISTER = VFS_FIRST,
    VFS_MOUNT,
    VFS_UNMOUNT,
    VFS_LOOKUP,
    VFS_OPEN,
    VFS_CREATE,
    VFS_CLOSE,
    VFS_READ,
    VFS_WRITE,
    VFS_SEEK,
    VFS_RENAME,
    VFS_UNLINK,
    VFS_LAST,       /* keep this the last member of the enum */
} vfs_request_t;
 
 
/**
 * An instance of this structure is associated with a particular FS operation.
 * It tells VFS if the FS supports the operation or maybe if a default one
 * should be used.
 */
typedef enum {
    VFS_OP_NULL = 0,
    VFS_OP_DEFAULT,
    VFS_OP_DEFINED
} vfs_op_t;
 
#define FS_NAME_MAXLEN  20
 
/**
 * A structure like this is passed to VFS by each individual FS upon its
 * registration. It assosiates a human-readable identifier with each
 * registered FS. More importantly, through this structure, the FS announces
 * what operations it supports.
 */
typedef struct {
    /** Unique identifier of the fs. */
    char name[FS_NAME_MAXLEN + 1];
   
    /** Operations. */
    vfs_op_t ops[VFS_LAST - VFS_FIRST];
} vfs_info_t;
 
/**
 * A structure like this will be allocated for each registered file system.
 */
typedef struct {
    link_t fs_link;
    vfs_info_t vfs_info;
    int fs_handle;
    atomic_t phone_futex;   /**< Phone serializing futex. */
    ipcarg_t phone;
} fs_info_t;
 
/**
 * VFS_PAIR uniquely represents a file system instance.
 */
#define VFS_PAIR    \
    int fs_handle;  \
    int dev_handle; 
 
/**
 * VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
 * doesn't contain any state. For a stateful structure, see vfs_node_t.
 *
 * @note    fs_handle, dev_handle and index are meant to be returned in one
 *      IPC reply.
 */
#define VFS_TRIPLET \
    VFS_PAIR;   \
    uint64_t index;
 
typedef struct {
    VFS_PAIR;
} vfs_pair_t;
 
typedef struct {
    VFS_TRIPLET;
} vfs_triplet_t;
 
/**
 * Instances of this type represent an active, in-memory VFS node and any state
 * which may be associated with it.
 */
typedef struct {
    VFS_TRIPLET;        /**< Identity of the node. */
    unsigned refcnt;    /**< Usage counter. */
    link_t nh_link;     /**< Node hash-table link. */
 
    /** Holding this futex prevents modifications of the node's contents. */
    atomic_t contents_futex;
} vfs_node_t;
 
/**
 * Instances of this type represent an open file. If the file is opened by more
 * than one task, there will be a separate structure allocated for each task.
 */
typedef struct {
    vfs_node_t *node;
   
    /** Number of file handles referencing this file. */
    unsigned refcnt;
 
    /** Current position in the file. */
    off_t pos;
} vfs_file_t;
 
extern link_t fs_head;      /**< List of registered file systems. */
 
extern vfs_triplet_t rootfs;    /**< Root node of the root file system. */
 
#define MAX_PATH_LEN        (64 * 1024)
 
#define PLB_SIZE        (2 * MAX_PATH_LEN)
 
/** Each instance of this type describes one path lookup in progress. */
typedef struct {
    link_t  plb_link;   /**< Active PLB entries list link. */
    unsigned index;     /**< Index of the first character in PLB. */
    size_t len;     /**< Number of characters in this PLB entry. */
} plb_entry_t;
 
extern atomic_t plb_futex;  /**< Futex protecting plb and plb_head. */
extern uint8_t *plb;        /**< Path Lookup Buffer */
extern link_t plb_head;     /**< List of active PLB entries. */
 
/** Holding this futex prevents extern changes in file system namespace. */
atomic_t namespace_futex;
 
extern int vfs_grab_phone(int);
extern void vfs_release_phone(int);
 
extern int fs_name_to_handle(char *, bool);
 
extern int vfs_lookup_internal(char *, size_t, vfs_triplet_t *, vfs_pair_t *);
 
extern bool vfs_nodes_init(void);
extern vfs_node_t *vfs_node_get(vfs_triplet_t *);
extern void vfs_node_put(vfs_node_t *);
 
#define MAX_OPEN_FILES  128
 
extern bool vfs_files_init(void);
extern vfs_file_t *vfs_file_get(int);
extern int vfs_fd_alloc(void);
extern void vfs_fd_free(int);
 
extern void vfs_file_addref(vfs_file_t *);
extern void vfs_file_delref(vfs_file_t *);
 
extern void vfs_node_addref(vfs_node_t *);
extern void vfs_node_delref(vfs_node_t *);
 
extern void vfs_register(ipc_callid_t, ipc_call_t *);
extern void vfs_mount(ipc_callid_t, ipc_call_t *);
extern void vfs_open(ipc_callid_t, ipc_call_t *);
extern void vfs_read(ipc_callid_t, ipc_call_t *);
extern void vfs_write(ipc_callid_t, ipc_call_t *);
 
#endif
 
/**
 * @}
 */
 

Rev 2666	Rev 2679
1	/*	1	/*
2	* Copyright (c) 2007 Jakub Jermar	2	* Copyright (c) 2007 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	#ifndef VFS_VFS_H_	33	#ifndef VFS_VFS_H_
34	#define VFS_VFS_H_	34	#define VFS_VFS_H_
35		35
36	#include <ipc/ipc.h>	36	#include <ipc/ipc.h>
37	#include <libadt/list.h>	37	#include <libadt/list.h>
38	#include <atomic.h>	38	#include <atomic.h>
39	#include <sys/types.h>	39	#include <sys/types.h>
40	#include <bool.h>	40	#include <bool.h>
41		41
42	#define dprintf(...) printf(__VA_ARGS__)	42	#define dprintf(...) printf(__VA_ARGS__)
43		43
44	#define VFS_FIRST IPC_FIRST_USER_METHOD	44	#define VFS_FIRST IPC_FIRST_USER_METHOD
45		45
46	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)	46	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)
47		47
48	typedef enum {	48	typedef enum {
49	VFS_REGISTER = VFS_FIRST,	49	VFS_REGISTER = VFS_FIRST,
50	VFS_MOUNT,	50	VFS_MOUNT,
51	VFS_UNMOUNT,	51	VFS_UNMOUNT,
52	VFS_LOOKUP,	52	VFS_LOOKUP,
53	VFS_OPEN,	53	VFS_OPEN,
54	VFS_CREATE,	54	VFS_CREATE,
55	VFS_CLOSE,	55	VFS_CLOSE,
56	VFS_READ,	56	VFS_READ,
57	VFS_WRITE,	57	VFS_WRITE,
58	VFS_SEEK,	58	VFS_SEEK,
59	VFS_RENAME,	59	VFS_RENAME,
60	VFS_UNLINK,	60	VFS_UNLINK,
61	VFS_LAST, /* keep this the last member of the enum */	61	VFS_LAST, /* keep this the last member of the enum */
62	} vfs_request_t;	62	} vfs_request_t;
63		63
64		64
65	/**	65	/**
66	* An instance of this structure is associated with a particular FS operation.	66	* An instance of this structure is associated with a particular FS operation.
67	* It tells VFS if the FS supports the operation or maybe if a default one	67	* It tells VFS if the FS supports the operation or maybe if a default one
68	* should be used.	68	* should be used.
69	*/	69	*/
70	typedef enum {	70	typedef enum {
71	VFS_OP_NULL = 0,	71	VFS_OP_NULL = 0,
72	VFS_OP_DEFAULT,	72	VFS_OP_DEFAULT,
73	VFS_OP_DEFINED	73	VFS_OP_DEFINED
74	} vfs_op_t;	74	} vfs_op_t;
75		75
76	#define FS_NAME_MAXLEN 20	76	#define FS_NAME_MAXLEN 20
77		77
78	/**	78	/**
79	* A structure like this is passed to VFS by each individual FS upon its	79	* A structure like this is passed to VFS by each individual FS upon its
80	* registration. It assosiates a human-readable identifier with each	80	* registration. It assosiates a human-readable identifier with each
81	* registered FS. More importantly, through this structure, the FS announces	81	* registered FS. More importantly, through this structure, the FS announces
82	* what operations it supports.	82	* what operations it supports.
83	*/	83	*/
84	typedef struct {	84	typedef struct {
85	/** Unique identifier of the fs. */	85	/** Unique identifier of the fs. */
86	char name[FS_NAME_MAXLEN + 1];	86	char name[FS_NAME_MAXLEN + 1];
87		87
88	/** Operations. */	88	/** Operations. */
89	vfs_op_t ops[VFS_LAST - VFS_FIRST];	89	vfs_op_t ops[VFS_LAST - VFS_FIRST];
90	} vfs_info_t;	90	} vfs_info_t;
91		91
92	/**	92	/**
93	* A structure like this will be allocated for each registered file system.	93	* A structure like this will be allocated for each registered file system.
94	*/	94	*/
95	typedef struct {	95	typedef struct {
96	link_t fs_link;	96	link_t fs_link;
97	vfs_info_t vfs_info;	97	vfs_info_t vfs_info;
98	int fs_handle;	98	int fs_handle;
99	atomic_t phone_futex; /*< Phone serializing futex. /	99	atomic_t phone_futex; /*< Phone serializing futex. /
100	ipcarg_t phone;	100	ipcarg_t phone;
101	} fs_info_t;	101	} fs_info_t;
102		102
103	/**	103	/**
104	* VFS_PAIR uniquely represents a file system instance.	104	* VFS_PAIR uniquely represents a file system instance.
105	*/	105	*/
106	#define VFS_PAIR \	106	#define VFS_PAIR \
107	int fs_handle; \	107	int fs_handle; \
108	int dev_handle;	108	int dev_handle;
109		109
110	/**	110	/**
111	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but	111	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
112	* doesn't contain any state. For a stateful structure, see vfs_node_t.	112	* doesn't contain any state. For a stateful structure, see vfs_node_t.
113	*	113	*
114	* @note fs_handle, dev_handle and index are meant to be returned in one	114	* @note fs_handle, dev_handle and index are meant to be returned in one
115	* IPC reply.	115	* IPC reply.
116	*/	116	*/
117	#define VFS_TRIPLET \	117	#define VFS_TRIPLET \
118	VFS_PAIR; \	118	VFS_PAIR; \
119	uint64_t index;	119	uint64_t index;
120		120
121	typedef struct {	121	typedef struct {
122	VFS_PAIR;	122	VFS_PAIR;
123	} vfs_pair_t;	123	} vfs_pair_t;
124		124
125	typedef struct {	125	typedef struct {
126	VFS_TRIPLET;	126	VFS_TRIPLET;
127	} vfs_triplet_t;	127	} vfs_triplet_t;
128		128
129	/**	129	/**
130	* Instances of this type represent an active, in-memory VFS node and any state	130	* Instances of this type represent an active, in-memory VFS node and any state
131	* which may be associated with it.	131	* which may be associated with it.
132	*/	132	*/
133	typedef struct {	133	typedef struct {
134	VFS_TRIPLET; /*< Identity of the node. /	134	VFS_TRIPLET; /*< Identity of the node. /
135	unsigned refcnt; /*< Usage counter. /	135	unsigned refcnt; /*< Usage counter. /
136	link_t nh_link; /*< Node hash-table link. /	136	link_t nh_link; /*< Node hash-table link. /
-		137
-		138	/** Holding this futex prevents modifications of the node's contents. */
-		139	atomic_t contents_futex;
137	} vfs_node_t;	140	} vfs_node_t;
138		141
139	/**	142	/**
140	* Instances of this type represent an open file. If the file is opened by more	143	* Instances of this type represent an open file. If the file is opened by more
141	* than one task, there will be a separate structure allocated for each task.	144	* than one task, there will be a separate structure allocated for each task.
142	*/	145	*/
143	typedef struct {	146	typedef struct {
144	vfs_node_t *node;	147	vfs_node_t *node;
145		148
146	/** Number of file handles referencing this file. */	149	/** Number of file handles referencing this file. */
147	unsigned refcnt;	150	unsigned refcnt;
148		151
149	/** Current position in the file. */	152	/** Current position in the file. */
150	off_t pos;	153	off_t pos;
151	} vfs_file_t;	154	} vfs_file_t;
152		155
153	extern link_t fs_head; /*< List of registered file systems. /	156	extern link_t fs_head; /*< List of registered file systems. /
154		157
155	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /	158	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /
156		159
157	#define MAX_PATH_LEN (64 * 1024)	160	#define MAX_PATH_LEN (64 * 1024)
158		161
159	#define PLB_SIZE (2 * MAX_PATH_LEN)	162	#define PLB_SIZE (2 * MAX_PATH_LEN)
160		163
161	/** Each instance of this type describes one path lookup in progress. */	164	/** Each instance of this type describes one path lookup in progress. */
162	typedef struct {	165	typedef struct {
163	link_t plb_link; /*< Active PLB entries list link. /	166	link_t plb_link; /*< Active PLB entries list link. /
164	unsigned index; /*< Index of the first character in PLB. /	167	unsigned index; /*< Index of the first character in PLB. /
165	size_t len; /*< Number of characters in this PLB entry. /	168	size_t len; /*< Number of characters in this PLB entry. /
166	} plb_entry_t;	169	} plb_entry_t;
167		170
168	extern atomic_t plb_futex; /*< Futex protecting plb and plb_head. /	171	extern atomic_t plb_futex; /*< Futex protecting plb and plb_head. /
169	extern uint8_t plb; /< Path Lookup Buffer /	172	extern uint8_t plb; /< Path Lookup Buffer /
170	extern link_t plb_head; /*< List of active PLB entries. /	173	extern link_t plb_head; /*< List of active PLB entries. /
171		174
172	extern atomic_t unlink_futex; /*< VFS_{CREATE\|OPEN\|UNLINK} serialization. /	175	/** Holding this futex prevents extern changes in file system namespace. */
-		176	atomic_t namespace_futex;
173		177
174	extern int vfs_grab_phone(int);	178	extern int vfs_grab_phone(int);
175	extern void vfs_release_phone(int);	179	extern void vfs_release_phone(int);
176		180
177	extern int fs_name_to_handle(char *, bool);	181	extern int fs_name_to_handle(char *, bool);
178		182
179	extern int vfs_lookup_internal(char , size_t, vfs_triplet_t , vfs_pair_t *);	183	extern int vfs_lookup_internal(char , size_t, vfs_triplet_t , vfs_pair_t *);
180		184
181	extern bool vfs_nodes_init(void);	185	extern bool vfs_nodes_init(void);
182	extern vfs_node_t vfs_node_get(vfs_triplet_t );	186	extern vfs_node_t vfs_node_get(vfs_triplet_t );
183	extern void vfs_node_put(vfs_node_t *);	187	extern void vfs_node_put(vfs_node_t *);
184		188
185	#define MAX_OPEN_FILES 128	189	#define MAX_OPEN_FILES 128
186		190
187	extern bool vfs_files_init(void);	191	extern bool vfs_files_init(void);
188	extern vfs_file_t *vfs_file_get(int);	192	extern vfs_file_t *vfs_file_get(int);
189	extern int vfs_fd_alloc(void);	193	extern int vfs_fd_alloc(void);
190	extern void vfs_fd_free(int);	194	extern void vfs_fd_free(int);
191		195
192	extern void vfs_file_addref(vfs_file_t *);	196	extern void vfs_file_addref(vfs_file_t *);
193	extern void vfs_file_delref(vfs_file_t *);	197	extern void vfs_file_delref(vfs_file_t *);
194		198
195	extern void vfs_node_addref(vfs_node_t *);	199	extern void vfs_node_addref(vfs_node_t *);
196	extern void vfs_node_delref(vfs_node_t *);	200	extern void vfs_node_delref(vfs_node_t *);
197		201
198	extern void vfs_register(ipc_callid_t, ipc_call_t *);	202	extern void vfs_register(ipc_callid_t, ipc_call_t *);
199	extern void vfs_mount(ipc_callid_t, ipc_call_t *);	203	extern void vfs_mount(ipc_callid_t, ipc_call_t *);
200	extern void vfs_open(ipc_callid_t, ipc_call_t *);	204	extern void vfs_open(ipc_callid_t, ipc_call_t *);
201	extern void vfs_read(ipc_callid_t, ipc_call_t *);	205	extern void vfs_read(ipc_callid_t, ipc_call_t *);
202	extern void vfs_write(ipc_callid_t, ipc_call_t *);	206	extern void vfs_write(ipc_callid_t, ipc_call_t *);
203		207
204	#endif	208	#endif
205		209
206	/**	210	/**
207	* @}	211	* @}
208	*/	212	*/
209		213

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(root)/trunk/uspace/srv/vfs/vfs.h – Rev 2666 → 2679