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 <futex.h>
#include <rwlock.h>
#include <sys/types.h>
#include <bool.h>
 
// FIXME: according to CONFIG_DEBUG
// #define dprintf(...) printf(__VA_ARGS__)
 
#define dprintf(...)
 
#define VFS_FIRST   IPC_FIRST_USER_METHOD
 
 
 
/* Basic types. */
typedef int16_t fs_handle_t;
typedef int16_t dev_handle_t;
typedef uint32_t fs_index_t;
 
typedef enum {
    VFS_READ = VFS_FIRST,
    VFS_WRITE,
    VFS_TRUNCATE,
    VFS_MOUNT,
    VFS_UNMOUNT,
    VFS_LAST_CMN,   /* keep this the last member of this enum */
} vfs_request_cmn_t;
 
typedef enum {
    VFS_LOOKUP = VFS_LAST_CMN,
    VFS_MOUNTED,
    VFS_DESTROY,
    VFS_LAST_CLNT,  /* keep this the last member of this enum */
} vfs_request_clnt_t;
 
typedef enum {
    VFS_REGISTER = VFS_LAST_CMN,
    VFS_OPEN,
    VFS_CLOSE,
    VFS_SEEK,
    VFS_MKDIR,
    VFS_UNLINK,
    VFS_RENAME,
    VFS_LAST_SRV,   /* keep this the last member of this enum */
} vfs_request_srv_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.
 */
typedef struct {
    /** Unique identifier of the fs. */
    char name[FS_NAME_MAXLEN + 1];
 
 
 
} 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;
    fs_handle_t fs_handle;
    futex_t phone_futex;    /**< Phone serializing futex. */
    ipcarg_t phone;
} fs_info_t;
 
/**
 * VFS_PAIR uniquely represents a file system instance.
 */
#define VFS_PAIR        \
    fs_handle_t fs_handle;  \
    dev_handle_t 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;   \
    fs_index_t index;
 
typedef struct {
    VFS_PAIR;
} vfs_pair_t;
 
typedef struct {
    VFS_TRIPLET;
} vfs_triplet_t;
 
/*
 * Lookup flags.
 */
/**
 * No lookup flags used.
 */
#define L_NONE      0
/**
 * Lookup will succeed only if the object is a regular file.  If L_CREATE is
 * specified, an empty file will be created. This flag is mutually exclusive
 * with L_DIRECTORY.
 */
#define L_FILE      1
/**
 * Lookup wil succeed only if the object is a directory. If L_CREATE is
 * specified, an empty directory will be created. This flag is mutually
 * exclusive with L_FILE.
 */
#define L_DIRECTORY 2
/**
 * When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the
 * object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
 */
#define L_EXCLUSIVE 4
/**
 * L_CREATE is used for creating both regular files and directories.
 */
#define L_CREATE    8
/**
 * L_LINK is used for linking to an already existing nodes.
 */
#define L_LINK      16
/**
 * L_UNLINK is used to remove leaves from the file system namespace. This flag
 * cannot be passed directly by the client, but will be set by VFS during
 * VFS_UNLINK.
 */
#define L_UNLINK    32  
/**
 * L_PARENT performs a lookup but returns the triplet of the parent node.
 * This flag may not be combined with any other lookup flag.
 */
#define L_PARENT    64  
 
typedef enum vfs_node_type {
    VFS_NODE_UNKNOWN,
    VFS_NODE_FILE,
    VFS_NODE_DIRECTORY,
} vfs_node_type_t;
 
typedef struct {
    vfs_triplet_t triplet;
    vfs_node_type_t type;
    size_t size;
    unsigned lnkcnt;
} vfs_lookup_res_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. */
 
    /**
     * Usage counter.  This includes, but is not limited to, all vfs_file_t
     * structures that reference this node.
     */
    unsigned refcnt;
   
    /** Number of names this node has in the file system namespace. */
    unsigned lnkcnt;
 
    link_t nh_link;     /**< Node hash-table link. */
 
    vfs_node_type_t type;   /**< Partial info about the node type. */
 
    size_t size;        /**< Cached size if the node is a file. */
 
    /**
     * 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 {
    /** Serializes access to this open file. */
    futex_t lock;
 
    vfs_node_t *node;
   
    /** Number of file handles referencing this file. */
    unsigned refcnt;
 
    /** Append on write. */
    bool append;
 
    /** Current position in the file. */
    off_t pos;
} vfs_file_t;
 
extern futex_t nodes_futex;
 
extern link_t fs_head;      /**< List of registered file systems. */
 
extern vfs_pair_t rootfs;   /**< 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 futex_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(fs_handle_t);
extern void vfs_release_phone(int);
 
extern fs_handle_t fs_name_to_handle(char *, bool);
 
extern int vfs_lookup_internal(char *, int, vfs_lookup_res_t *, vfs_pair_t *,
    ...);
 
extern bool vfs_nodes_init(void);
extern vfs_node_t *vfs_node_get(vfs_lookup_res_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 int 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_close(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 *);
extern void vfs_seek(ipc_callid_t, ipc_call_t *);
extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
extern void vfs_unlink(ipc_callid_t, ipc_call_t *);
extern void vfs_rename(ipc_callid_t, ipc_call_t *);
 
#endif
 
/**
 * @}
 */
 

Rev 3653	Rev 3845
1	/*	1	/*
2	* Copyright (c) 2008 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 <futex.h>	38	#include <futex.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	// FIXME: according to CONFIG_DEBUG	43	// FIXME: according to CONFIG_DEBUG
44	// #define dprintf(...) printf(__VA_ARGS__)	44	// #define dprintf(...) printf(__VA_ARGS__)
45		45
46	#define dprintf(...)	46	#define dprintf(...)
47		47
48	#define VFS_FIRST IPC_FIRST_USER_METHOD	48	#define VFS_FIRST IPC_FIRST_USER_METHOD
49		49
50	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)	-
51		-
52	/* Basic types. */	50	/* Basic types. */
53	typedef int16_t fs_handle_t;	51	typedef int16_t fs_handle_t;
54	typedef int16_t dev_handle_t;	52	typedef int16_t dev_handle_t;
55	typedef uint32_t fs_index_t;	53	typedef uint32_t fs_index_t;
56		54
57	typedef enum {	55	typedef enum {
58	VFS_READ = VFS_FIRST,	56	VFS_READ = VFS_FIRST,
59	VFS_WRITE,	57	VFS_WRITE,
60	VFS_TRUNCATE,	58	VFS_TRUNCATE,
61	VFS_MOUNT,	59	VFS_MOUNT,
62	VFS_UNMOUNT,	60	VFS_UNMOUNT,
63	VFS_LAST_CMN, /* keep this the last member of this enum */	61	VFS_LAST_CMN, /* keep this the last member of this enum */
64	} vfs_request_cmn_t;	62	} vfs_request_cmn_t;
65		63
66	typedef enum {	64	typedef enum {
67	VFS_LOOKUP = VFS_LAST_CMN,	65	VFS_LOOKUP = VFS_LAST_CMN,
68	VFS_MOUNTED,	66	VFS_MOUNTED,
69	VFS_DESTROY,	67	VFS_DESTROY,
70	VFS_LAST_CLNT, /* keep this the last member of this enum */	68	VFS_LAST_CLNT, /* keep this the last member of this enum */
71	} vfs_request_clnt_t;	69	} vfs_request_clnt_t;
72		70
73	typedef enum {	71	typedef enum {
74	VFS_REGISTER = VFS_LAST_CMN,	72	VFS_REGISTER = VFS_LAST_CMN,
75	VFS_OPEN,	73	VFS_OPEN,
76	VFS_CLOSE,	74	VFS_CLOSE,
77	VFS_SEEK,	75	VFS_SEEK,
78	VFS_MKDIR,	76	VFS_MKDIR,
79	VFS_UNLINK,	77	VFS_UNLINK,
80	VFS_RENAME,	78	VFS_RENAME,
81	VFS_LAST_SRV, /* keep this the last member of this enum */	79	VFS_LAST_SRV, /* keep this the last member of this enum */
82	} vfs_request_srv_t;	80	} vfs_request_srv_t;
83		81
84		-
85	/**	-
86	* An instance of this structure is associated with a particular FS operation.	-
87	* It tells VFS if the FS supports the operation or maybe if a default one	-
88	* should be used.	-
89	*/	-
90	typedef enum {	-
91	VFS_OP_NULL = 0,	-
92	VFS_OP_DEFAULT,	-
93	VFS_OP_DEFINED	-
94	} vfs_op_t;	-
95		-
96	#define FS_NAME_MAXLEN 20	82	#define FS_NAME_MAXLEN 20
97		83
98	/**	84	/**
99	* A structure like this is passed to VFS by each individual FS upon its	85	* A structure like this is passed to VFS by each individual FS upon its
100	* registration. It assosiates a human-readable identifier with each	86	* registration. It assosiates a human-readable identifier with each
101	* registered FS. More importantly, through this structure, the FS announces	-
102	* what operations it supports.	87	* registered FS.
103	*/	88	*/
104	typedef struct {	89	typedef struct {
105	/** Unique identifier of the fs. */	90	/** Unique identifier of the fs. */
106	char name[FS_NAME_MAXLEN + 1];	91	char name[FS_NAME_MAXLEN + 1];
107		-
108	/** Operations. */	-
109	vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];	-
110	} vfs_info_t;	92	} vfs_info_t;
111		93
112	/**	94	/**
113	* A structure like this will be allocated for each registered file system.	95	* A structure like this will be allocated for each registered file system.
114	*/	96	*/
115	typedef struct {	97	typedef struct {
116	link_t fs_link;	98	link_t fs_link;
117	vfs_info_t vfs_info;	99	vfs_info_t vfs_info;
118	fs_handle_t fs_handle;	100	fs_handle_t fs_handle;
119	futex_t phone_futex; /*< Phone serializing futex. /	101	futex_t phone_futex; /*< Phone serializing futex. /
120	ipcarg_t phone;	102	ipcarg_t phone;
121	} fs_info_t;	103	} fs_info_t;
122		104
123	/**	105	/**
124	* VFS_PAIR uniquely represents a file system instance.	106	* VFS_PAIR uniquely represents a file system instance.
125	*/	107	*/
126	#define VFS_PAIR \	108	#define VFS_PAIR \
127	fs_handle_t fs_handle; \	109	fs_handle_t fs_handle; \
128	dev_handle_t dev_handle;	110	dev_handle_t dev_handle;
129		111
130	/**	112	/**
131	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but	113	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
132	* doesn't contain any state. For a stateful structure, see vfs_node_t.	114	* doesn't contain any state. For a stateful structure, see vfs_node_t.
133	*	115	*
134	* @note fs_handle, dev_handle and index are meant to be returned in one	116	* @note fs_handle, dev_handle and index are meant to be returned in one
135	* IPC reply.	117	* IPC reply.
136	*/	118	*/
137	#define VFS_TRIPLET \	119	#define VFS_TRIPLET \
138	VFS_PAIR; \	120	VFS_PAIR; \
139	fs_index_t index;	121	fs_index_t index;
140		122
141	typedef struct {	123	typedef struct {
142	VFS_PAIR;	124	VFS_PAIR;
143	} vfs_pair_t;	125	} vfs_pair_t;
144		126
145	typedef struct {	127	typedef struct {
146	VFS_TRIPLET;	128	VFS_TRIPLET;
147	} vfs_triplet_t;	129	} vfs_triplet_t;
148		130
149	/*	131	/*
150	* Lookup flags.	132	* Lookup flags.
151	*/	133	*/
152	/**	134	/**
153	* No lookup flags used.	135	* No lookup flags used.
154	*/	136	*/
155	#define L_NONE 0	137	#define L_NONE 0
156	/**	138	/**
157	* Lookup will succeed only if the object is a regular file. If L_CREATE is	139	* Lookup will succeed only if the object is a regular file. If L_CREATE is
158	* specified, an empty file will be created. This flag is mutually exclusive	140	* specified, an empty file will be created. This flag is mutually exclusive
159	* with L_DIRECTORY.	141	* with L_DIRECTORY.
160	*/	142	*/
161	#define L_FILE 1	143	#define L_FILE 1
162	/**	144	/**
163	* Lookup wil succeed only if the object is a directory. If L_CREATE is	145	* Lookup wil succeed only if the object is a directory. If L_CREATE is
164	* specified, an empty directory will be created. This flag is mutually	146	* specified, an empty directory will be created. This flag is mutually
165	* exclusive with L_FILE.	147	* exclusive with L_FILE.
166	*/	148	*/
167	#define L_DIRECTORY 2	149	#define L_DIRECTORY 2
168	/**	150	/**
169	* When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the	151	* When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the
170	* object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.	152	* object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
171	*/	153	*/
172	#define L_EXCLUSIVE 4	154	#define L_EXCLUSIVE 4
173	/**	155	/**
174	* L_CREATE is used for creating both regular files and directories.	156	* L_CREATE is used for creating both regular files and directories.
175	*/	157	*/
176	#define L_CREATE 8	158	#define L_CREATE 8
177	/**	159	/**
178	* L_LINK is used for linking to an already existing nodes.	160	* L_LINK is used for linking to an already existing nodes.
179	*/	161	*/
180	#define L_LINK 16	162	#define L_LINK 16
181	/**	163	/**
182	* L_UNLINK is used to remove leaves from the file system namespace. This flag	164	* L_UNLINK is used to remove leaves from the file system namespace. This flag
183	* cannot be passed directly by the client, but will be set by VFS during	165	* cannot be passed directly by the client, but will be set by VFS during
184	* VFS_UNLINK.	166	* VFS_UNLINK.
185	*/	167	*/
186	#define L_UNLINK 32	168	#define L_UNLINK 32
187	/**	169	/**
188	* L_PARENT performs a lookup but returns the triplet of the parent node.	170	* L_PARENT performs a lookup but returns the triplet of the parent node.
189	* This flag may not be combined with any other lookup flag.	171	* This flag may not be combined with any other lookup flag.
190	*/	172	*/
191	#define L_PARENT 64	173	#define L_PARENT 64
192		174
193	typedef enum vfs_node_type {	175	typedef enum vfs_node_type {
194	VFS_NODE_UNKNOWN,	176	VFS_NODE_UNKNOWN,
195	VFS_NODE_FILE,	177	VFS_NODE_FILE,
196	VFS_NODE_DIRECTORY,	178	VFS_NODE_DIRECTORY,
197	} vfs_node_type_t;	179	} vfs_node_type_t;
198		180
199	typedef struct {	181	typedef struct {
200	vfs_triplet_t triplet;	182	vfs_triplet_t triplet;
201	vfs_node_type_t type;	183	vfs_node_type_t type;
202	size_t size;	184	size_t size;
203	unsigned lnkcnt;	185	unsigned lnkcnt;
204	} vfs_lookup_res_t;	186	} vfs_lookup_res_t;
205		187
206	/**	188	/**
207	* Instances of this type represent an active, in-memory VFS node and any state	189	* Instances of this type represent an active, in-memory VFS node and any state
208	* which may be associated with it.	190	* which may be associated with it.
209	*/	191	*/
210	typedef struct {	192	typedef struct {
211	VFS_TRIPLET; /*< Identity of the node. /	193	VFS_TRIPLET; /*< Identity of the node. /
212		194
213	/**	195	/**
214	* Usage counter. This includes, but is not limited to, all vfs_file_t	196	* Usage counter. This includes, but is not limited to, all vfs_file_t
215	* structures that reference this node.	197	* structures that reference this node.
216	*/	198	*/
217	unsigned refcnt;	199	unsigned refcnt;
218		200
219	/** Number of names this node has in the file system namespace. */	201	/** Number of names this node has in the file system namespace. */
220	unsigned lnkcnt;	202	unsigned lnkcnt;
221		203
222	link_t nh_link; /*< Node hash-table link. /	204	link_t nh_link; /*< Node hash-table link. /
223		205
224	vfs_node_type_t type; /*< Partial info about the node type. /	206	vfs_node_type_t type; /*< Partial info about the node type. /
225		207
226	size_t size; /*< Cached size if the node is a file. /	208	size_t size; /*< Cached size if the node is a file. /
227		209
228	/**	210	/**
229	* Holding this rwlock prevents modifications of the node's contents.	211	* Holding this rwlock prevents modifications of the node's contents.
230	*/	212	*/
231	rwlock_t contents_rwlock;	213	rwlock_t contents_rwlock;
232	} vfs_node_t;	214	} vfs_node_t;
233		215
234	/**	216	/**
235	* Instances of this type represent an open file. If the file is opened by more	217	* Instances of this type represent an open file. If the file is opened by more
236	* than one task, there will be a separate structure allocated for each task.	218	* than one task, there will be a separate structure allocated for each task.
237	*/	219	*/
238	typedef struct {	220	typedef struct {
239	/** Serializes access to this open file. */	221	/** Serializes access to this open file. */
240	futex_t lock;	222	futex_t lock;
241		223
242	vfs_node_t *node;	224	vfs_node_t *node;
243		225
244	/** Number of file handles referencing this file. */	226	/** Number of file handles referencing this file. */
245	unsigned refcnt;	227	unsigned refcnt;
246		228
247	/** Append on write. */	229	/** Append on write. */
248	bool append;	230	bool append;
249		231
250	/** Current position in the file. */	232	/** Current position in the file. */
251	off_t pos;	233	off_t pos;
252	} vfs_file_t;	234	} vfs_file_t;
253		235
254	extern futex_t nodes_futex;	236	extern futex_t nodes_futex;
255		237
256	extern link_t fs_head; /*< List of registered file systems. /	238	extern link_t fs_head; /*< List of registered file systems. /
257		239
258	extern vfs_pair_t rootfs; /*< Root file system. /	240	extern vfs_pair_t rootfs; /*< Root file system. /
259		241
260	#define MAX_PATH_LEN (64 * 1024)	242	#define MAX_PATH_LEN (64 * 1024)
261		243
262	#define PLB_SIZE (2 * MAX_PATH_LEN)	244	#define PLB_SIZE (2 * MAX_PATH_LEN)
263		245
264	/** Each instance of this type describes one path lookup in progress. */	246	/** Each instance of this type describes one path lookup in progress. */
265	typedef struct {	247	typedef struct {
266	link_t plb_link; /*< Active PLB entries list link. /	248	link_t plb_link; /*< Active PLB entries list link. /
267	unsigned index; /*< Index of the first character in PLB. /	249	unsigned index; /*< Index of the first character in PLB. /
268	size_t len; /*< Number of characters in this PLB entry. /	250	size_t len; /*< Number of characters in this PLB entry. /
269	} plb_entry_t;	251	} plb_entry_t;
270		252
271	extern futex_t plb_futex; /*< Futex protecting plb and plb_head. /	253	extern futex_t plb_futex; /*< Futex protecting plb and plb_head. /
272	extern uint8_t plb; /< Path Lookup Buffer /	254	extern uint8_t plb; /< Path Lookup Buffer /
273	extern link_t plb_head; /*< List of active PLB entries. /	255	extern link_t plb_head; /*< List of active PLB entries. /
274		256
275	/** Holding this rwlock prevents changes in file system namespace. */	257	/** Holding this rwlock prevents changes in file system namespace. */
276	extern rwlock_t namespace_rwlock;	258	extern rwlock_t namespace_rwlock;
277		259
278	extern int vfs_grab_phone(fs_handle_t);	260	extern int vfs_grab_phone(fs_handle_t);
279	extern void vfs_release_phone(int);	261	extern void vfs_release_phone(int);
280		262
281	extern fs_handle_t fs_name_to_handle(char *, bool);	263	extern fs_handle_t fs_name_to_handle(char *, bool);
282		264
283	extern int vfs_lookup_internal(char , int, vfs_lookup_res_t , vfs_pair_t *,	265	extern int vfs_lookup_internal(char , int, vfs_lookup_res_t , vfs_pair_t *,
284	...);	266	...);
285		267
286	extern bool vfs_nodes_init(void);	268	extern bool vfs_nodes_init(void);
287	extern vfs_node_t vfs_node_get(vfs_lookup_res_t );	269	extern vfs_node_t vfs_node_get(vfs_lookup_res_t );
288	extern void vfs_node_put(vfs_node_t *);	270	extern void vfs_node_put(vfs_node_t *);
289		271
290	#define MAX_OPEN_FILES 128	272	#define MAX_OPEN_FILES 128
291		273
292	extern bool vfs_files_init(void);	274	extern bool vfs_files_init(void);
293	extern vfs_file_t *vfs_file_get(int);	275	extern vfs_file_t *vfs_file_get(int);
294	extern int vfs_fd_alloc(void);	276	extern int vfs_fd_alloc(void);
295	extern int vfs_fd_free(int);	277	extern int vfs_fd_free(int);
296		278
297	extern void vfs_file_addref(vfs_file_t *);	279	extern void vfs_file_addref(vfs_file_t *);
298	extern void vfs_file_delref(vfs_file_t *);	280	extern void vfs_file_delref(vfs_file_t *);
299		281
300	extern void vfs_node_addref(vfs_node_t *);	282	extern void vfs_node_addref(vfs_node_t *);
301	extern void vfs_node_delref(vfs_node_t *);	283	extern void vfs_node_delref(vfs_node_t *);
302		284
303	extern void vfs_register(ipc_callid_t, ipc_call_t *);	285	extern void vfs_register(ipc_callid_t, ipc_call_t *);
304	extern void vfs_mount(ipc_callid_t, ipc_call_t *);	286	extern void vfs_mount(ipc_callid_t, ipc_call_t *);
305	extern void vfs_open(ipc_callid_t, ipc_call_t *);	287	extern void vfs_open(ipc_callid_t, ipc_call_t *);
306	extern void vfs_close(ipc_callid_t, ipc_call_t *);	288	extern void vfs_close(ipc_callid_t, ipc_call_t *);
307	extern void vfs_read(ipc_callid_t, ipc_call_t *);	289	extern void vfs_read(ipc_callid_t, ipc_call_t *);
308	extern void vfs_write(ipc_callid_t, ipc_call_t *);	290	extern void vfs_write(ipc_callid_t, ipc_call_t *);
309	extern void vfs_seek(ipc_callid_t, ipc_call_t *);	291	extern void vfs_seek(ipc_callid_t, ipc_call_t *);
310	extern void vfs_truncate(ipc_callid_t, ipc_call_t *);	292	extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
311	extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);	293	extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
312	extern void vfs_unlink(ipc_callid_t, ipc_call_t *);	294	extern void vfs_unlink(ipc_callid_t, ipc_call_t *);
313	extern void vfs_rename(ipc_callid_t, ipc_call_t *);	295	extern void vfs_rename(ipc_callid_t, ipc_call_t *);
314		296
315	#endif	297	#endif
316		298
317	/**	299	/**
318	* @}	300	* @}
319	*/	301	*/
320		302

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(root)/trunk/uspace/srv/vfs/vfs.h – Rev 3653 → 3845