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


/*
 * 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
 * @{
 */
 
#ifndef VFS_VFS_H_
#define VFS_VFS_H_
 
#include <ipc/ipc.h>
#include <libadt/list.h>
#include <atomic.h>
#include <rwlock.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 rwlock prevents modifications of the node's contents.
     */
    rwlock_t contents_rwlock;
} 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 rwlock prevents changes in file system namespace. */
extern rwlock_t namespace_rwlock;
 
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 2681	Rev 2682
1	/*	1	/*
2	* Copyright (c) 2007 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	#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 <rwlock.h>	39	#include <rwlock.h>
40	#include <sys/types.h>	40	#include <sys/types.h>
41	#include <bool.h>	41	#include <bool.h>
42		42
43	#define dprintf(...) printf(__VA_ARGS__)	43	#define dprintf(...) printf(__VA_ARGS__)
44		44
45	#define VFS_FIRST IPC_FIRST_USER_METHOD	45	#define VFS_FIRST IPC_FIRST_USER_METHOD
46		46
47	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)	47	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)
48		48
49	typedef enum {	49	typedef enum {
50	VFS_REGISTER = VFS_FIRST,	50	VFS_REGISTER = VFS_FIRST,
51	VFS_MOUNT,	51	VFS_MOUNT,
52	VFS_UNMOUNT,	52	VFS_UNMOUNT,
53	VFS_LOOKUP,	53	VFS_LOOKUP,
54	VFS_OPEN,	54	VFS_OPEN,
55	VFS_CREATE,	55	VFS_CREATE,
56	VFS_CLOSE,	56	VFS_CLOSE,
57	VFS_READ,	57	VFS_READ,
58	VFS_WRITE,	58	VFS_WRITE,
59	VFS_SEEK,	59	VFS_SEEK,
60	VFS_RENAME,	60	VFS_RENAME,
61	VFS_UNLINK,	61	VFS_UNLINK,
62	VFS_LAST, /* keep this the last member of the enum */	62	VFS_LAST, /* keep this the last member of the enum */
63	} vfs_request_t;	63	} vfs_request_t;
64		64
65		65
66	/**	66	/**
67	* An instance of this structure is associated with a particular FS operation.	67	* An instance of this structure is associated with a particular FS operation.
68	* It tells VFS if the FS supports the operation or maybe if a default one	68	* It tells VFS if the FS supports the operation or maybe if a default one
69	* should be used.	69	* should be used.
70	*/	70	*/
71	typedef enum {	71	typedef enum {
72	VFS_OP_NULL = 0,	72	VFS_OP_NULL = 0,
73	VFS_OP_DEFAULT,	73	VFS_OP_DEFAULT,
74	VFS_OP_DEFINED	74	VFS_OP_DEFINED
75	} vfs_op_t;	75	} vfs_op_t;
76		76
77	#define FS_NAME_MAXLEN 20	77	#define FS_NAME_MAXLEN 20
78		78
79	/**	79	/**
80	* A structure like this is passed to VFS by each individual FS upon its	80	* A structure like this is passed to VFS by each individual FS upon its
81	* registration. It assosiates a human-readable identifier with each	81	* registration. It assosiates a human-readable identifier with each
82	* registered FS. More importantly, through this structure, the FS announces	82	* registered FS. More importantly, through this structure, the FS announces
83	* what operations it supports.	83	* what operations it supports.
84	*/	84	*/
85	typedef struct {	85	typedef struct {
86	/** Unique identifier of the fs. */	86	/** Unique identifier of the fs. */
87	char name[FS_NAME_MAXLEN + 1];	87	char name[FS_NAME_MAXLEN + 1];
88		88
89	/** Operations. */	89	/** Operations. */
90	vfs_op_t ops[VFS_LAST - VFS_FIRST];	90	vfs_op_t ops[VFS_LAST - VFS_FIRST];
91	} vfs_info_t;	91	} vfs_info_t;
92		92
93	/**	93	/**
94	* A structure like this will be allocated for each registered file system.	94	* A structure like this will be allocated for each registered file system.
95	*/	95	*/
96	typedef struct {	96	typedef struct {
97	link_t fs_link;	97	link_t fs_link;
98	vfs_info_t vfs_info;	98	vfs_info_t vfs_info;
99	int fs_handle;	99	int fs_handle;
100	atomic_t phone_futex; /*< Phone serializing futex. /	100	atomic_t phone_futex; /*< Phone serializing futex. /
101	ipcarg_t phone;	101	ipcarg_t phone;
102	} fs_info_t;	102	} fs_info_t;
103		103
104	/**	104	/**
105	* VFS_PAIR uniquely represents a file system instance.	105	* VFS_PAIR uniquely represents a file system instance.
106	*/	106	*/
107	#define VFS_PAIR \	107	#define VFS_PAIR \
108	int fs_handle; \	108	int fs_handle; \
109	int dev_handle;	109	int dev_handle;
110		110
111	/**	111	/**
112	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but	112	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
113	* doesn't contain any state. For a stateful structure, see vfs_node_t.	113	* doesn't contain any state. For a stateful structure, see vfs_node_t.
114	*	114	*
115	* @note fs_handle, dev_handle and index are meant to be returned in one	115	* @note fs_handle, dev_handle and index are meant to be returned in one
116	* IPC reply.	116	* IPC reply.
117	*/	117	*/
118	#define VFS_TRIPLET \	118	#define VFS_TRIPLET \
119	VFS_PAIR; \	119	VFS_PAIR; \
120	uint64_t index;	120	uint64_t index;
121		121
122	typedef struct {	122	typedef struct {
123	VFS_PAIR;	123	VFS_PAIR;
124	} vfs_pair_t;	124	} vfs_pair_t;
125		125
126	typedef struct {	126	typedef struct {
127	VFS_TRIPLET;	127	VFS_TRIPLET;
128	} vfs_triplet_t;	128	} vfs_triplet_t;
129		129
130	/**	130	/**
131	* Instances of this type represent an active, in-memory VFS node and any state	131	* Instances of this type represent an active, in-memory VFS node and any state
132	* which may be associated with it.	132	* which may be associated with it.
133	*/	133	*/
134	typedef struct {	134	typedef struct {
135	VFS_TRIPLET; /*< Identity of the node. /	135	VFS_TRIPLET; /*< Identity of the node. /
136	unsigned refcnt; /*< Usage counter. /	136	unsigned refcnt; /*< Usage counter. /
137	link_t nh_link; /*< Node hash-table link. /	137	link_t nh_link; /*< Node hash-table link. /
138		138
-		139	/**
139	/** Holding this rwlock prevents modifications of the node's contents. */	140	* Holding this rwlock prevents modifications of the node's contents.
-		141	*/
140	atomic_t contents_rwlock;	142	rwlock_t contents_rwlock;
141	} vfs_node_t;	143	} vfs_node_t;
142		144
143	/**	145	/**
144	* Instances of this type represent an open file. If the file is opened by more	146	* Instances of this type represent an open file. If the file is opened by more
145	* than one task, there will be a separate structure allocated for each task.	147	* than one task, there will be a separate structure allocated for each task.
146	*/	148	*/
147	typedef struct {	149	typedef struct {
148	vfs_node_t *node;	150	vfs_node_t *node;
149		151
150	/** Number of file handles referencing this file. */	152	/** Number of file handles referencing this file. */
151	unsigned refcnt;	153	unsigned refcnt;
152		154
153	/** Current position in the file. */	155	/** Current position in the file. */
154	off_t pos;	156	off_t pos;
155	} vfs_file_t;	157	} vfs_file_t;
156		158
157	extern link_t fs_head; /*< List of registered file systems. /	159	extern link_t fs_head; /*< List of registered file systems. /
158		160
159	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /	161	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /
160		162
161	#define MAX_PATH_LEN (64 * 1024)	163	#define MAX_PATH_LEN (64 * 1024)
162		164
163	#define PLB_SIZE (2 * MAX_PATH_LEN)	165	#define PLB_SIZE (2 * MAX_PATH_LEN)
164		166
165	/** Each instance of this type describes one path lookup in progress. */	167	/** Each instance of this type describes one path lookup in progress. */
166	typedef struct {	168	typedef struct {
167	link_t plb_link; /*< Active PLB entries list link. /	169	link_t plb_link; /*< Active PLB entries list link. /
168	unsigned index; /*< Index of the first character in PLB. /	170	unsigned index; /*< Index of the first character in PLB. /
169	size_t len; /*< Number of characters in this PLB entry. /	171	size_t len; /*< Number of characters in this PLB entry. /
170	} plb_entry_t;	172	} plb_entry_t;
171		173
172	extern atomic_t plb_futex; /*< Futex protecting plb and plb_head. /	174	extern atomic_t plb_futex; /*< Futex protecting plb and plb_head. /
173	extern uint8_t plb; /< Path Lookup Buffer /	175	extern uint8_t plb; /< Path Lookup Buffer /
174	extern link_t plb_head; /*< List of active PLB entries. /	176	extern link_t plb_head; /*< List of active PLB entries. /
175		177
176	/** Holding this rwlock prevents changes in file system namespace. */	178	/** Holding this rwlock prevents changes in file system namespace. */
177	extern rwlock_t namespace_rwlock;	179	extern rwlock_t namespace_rwlock;
178		180
179	extern int vfs_grab_phone(int);	181	extern int vfs_grab_phone(int);
180	extern void vfs_release_phone(int);	182	extern void vfs_release_phone(int);
181		183
182	extern int fs_name_to_handle(char *, bool);	184	extern int fs_name_to_handle(char *, bool);
183		185
184	extern int vfs_lookup_internal(char , size_t, vfs_triplet_t , vfs_pair_t *);	186	extern int vfs_lookup_internal(char , size_t, vfs_triplet_t , vfs_pair_t *);
185		187
186	extern bool vfs_nodes_init(void);	188	extern bool vfs_nodes_init(void);
187	extern vfs_node_t vfs_node_get(vfs_triplet_t );	189	extern vfs_node_t vfs_node_get(vfs_triplet_t );
188	extern void vfs_node_put(vfs_node_t *);	190	extern void vfs_node_put(vfs_node_t *);
189		191
190	#define MAX_OPEN_FILES 128	192	#define MAX_OPEN_FILES 128
191		193
192	extern bool vfs_files_init(void);	194	extern bool vfs_files_init(void);
193	extern vfs_file_t *vfs_file_get(int);	195	extern vfs_file_t *vfs_file_get(int);
194	extern int vfs_fd_alloc(void);	196	extern int vfs_fd_alloc(void);
195	extern void vfs_fd_free(int);	197	extern void vfs_fd_free(int);
196		198
197	extern void vfs_file_addref(vfs_file_t *);	199	extern void vfs_file_addref(vfs_file_t *);
198	extern void vfs_file_delref(vfs_file_t *);	200	extern void vfs_file_delref(vfs_file_t *);
199		201
200	extern void vfs_node_addref(vfs_node_t *);	202	extern void vfs_node_addref(vfs_node_t *);
201	extern void vfs_node_delref(vfs_node_t *);	203	extern void vfs_node_delref(vfs_node_t *);
202		204
203	extern void vfs_register(ipc_callid_t, ipc_call_t *);	205	extern void vfs_register(ipc_callid_t, ipc_call_t *);
204	extern void vfs_mount(ipc_callid_t, ipc_call_t *);	206	extern void vfs_mount(ipc_callid_t, ipc_call_t *);
205	extern void vfs_open(ipc_callid_t, ipc_call_t *);	207	extern void vfs_open(ipc_callid_t, ipc_call_t *);
206	extern void vfs_read(ipc_callid_t, ipc_call_t *);	208	extern void vfs_read(ipc_callid_t, ipc_call_t *);
207	extern void vfs_write(ipc_callid_t, ipc_call_t *);	209	extern void vfs_write(ipc_callid_t, ipc_call_t *);
208		210
209	#endif	211	#endif
210		212
211	/**	213	/**
212	* @}	214	* @}
213	*/	215	*/
214		216

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(root)/trunk/uspace/srv/vfs/vfs.h – Rev 2681 → 2682