WebSVN – HelenOS – Diff – /branches/dynload/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
 
#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)   
 
/* 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_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;
 
 
/**
 * 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_CLNT - 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;
    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 struct {
    vfs_triplet_t triplet;
    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. */
    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_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 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 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_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 2927	Rev 3150
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	#define dprintf(...) printf(__VA_ARGS__)	44	// #define dprintf(...) printf(__VA_ARGS__)
-		45
-		46	#define dprintf(...)
44		47
45	#define VFS_FIRST IPC_FIRST_USER_METHOD	48	#define VFS_FIRST IPC_FIRST_USER_METHOD
46		49
47	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)	50	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)
48		51
49	/* Basic types. */	52	/* Basic types. */
50	typedef int16_t fs_handle_t;	53	typedef int16_t fs_handle_t;
51	typedef int16_t dev_handle_t;	54	typedef int16_t dev_handle_t;
52	typedef uint32_t fs_index_t;	55	typedef uint32_t fs_index_t;
53		56
54	typedef enum {	57	typedef enum {
55	VFS_READ = VFS_FIRST,	58	VFS_READ = VFS_FIRST,
56	VFS_WRITE,	59	VFS_WRITE,
57	VFS_TRUNCATE,	60	VFS_TRUNCATE,
58	VFS_MOUNT,	61	VFS_MOUNT,
59	VFS_UNMOUNT,	62	VFS_UNMOUNT,
60	VFS_LAST_CMN, /* keep this the last member of this enum */	63	VFS_LAST_CMN, /* keep this the last member of this enum */
61	} vfs_request_cmn_t;	64	} vfs_request_cmn_t;
62		65
63	typedef enum {	66	typedef enum {
64	VFS_LOOKUP = VFS_LAST_CMN,	67	VFS_LOOKUP = VFS_LAST_CMN,
65	VFS_DESTROY,	68	VFS_DESTROY,
66	VFS_LAST_CLNT, /* keep this the last member of this enum */	69	VFS_LAST_CLNT, /* keep this the last member of this enum */
67	} vfs_request_clnt_t;	70	} vfs_request_clnt_t;
68		71
69	typedef enum {	72	typedef enum {
70	VFS_REGISTER = VFS_LAST_CMN,	73	VFS_REGISTER = VFS_LAST_CMN,
71	VFS_OPEN,	74	VFS_OPEN,
72	VFS_CLOSE,	75	VFS_CLOSE,
73	VFS_SEEK,	76	VFS_SEEK,
74	VFS_MKDIR,	77	VFS_MKDIR,
75	VFS_UNLINK,	78	VFS_UNLINK,
76	VFS_RENAME,	79	VFS_RENAME,
77	VFS_LAST_SRV, /* keep this the last member of this enum */	80	VFS_LAST_SRV, /* keep this the last member of this enum */
78	} vfs_request_srv_t;	81	} vfs_request_srv_t;
79		82
80		83
81	/**	84	/**
82	* An instance of this structure is associated with a particular FS operation.	85	* An instance of this structure is associated with a particular FS operation.
83	* It tells VFS if the FS supports the operation or maybe if a default one	86	* It tells VFS if the FS supports the operation or maybe if a default one
84	* should be used.	87	* should be used.
85	*/	88	*/
86	typedef enum {	89	typedef enum {
87	VFS_OP_NULL = 0,	90	VFS_OP_NULL = 0,
88	VFS_OP_DEFAULT,	91	VFS_OP_DEFAULT,
89	VFS_OP_DEFINED	92	VFS_OP_DEFINED
90	} vfs_op_t;	93	} vfs_op_t;
91		94
92	#define FS_NAME_MAXLEN 20	95	#define FS_NAME_MAXLEN 20
93		96
94	/**	97	/**
95	* A structure like this is passed to VFS by each individual FS upon its	98	* A structure like this is passed to VFS by each individual FS upon its
96	* registration. It assosiates a human-readable identifier with each	99	* registration. It assosiates a human-readable identifier with each
97	* registered FS. More importantly, through this structure, the FS announces	100	* registered FS. More importantly, through this structure, the FS announces
98	* what operations it supports.	101	* what operations it supports.
99	*/	102	*/
100	typedef struct {	103	typedef struct {
101	/** Unique identifier of the fs. */	104	/** Unique identifier of the fs. */
102	char name[FS_NAME_MAXLEN + 1];	105	char name[FS_NAME_MAXLEN + 1];
103		106
104	/** Operations. */	107	/** Operations. */
105	vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];	108	vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];
106	} vfs_info_t;	109	} vfs_info_t;
107		110
108	/**	111	/**
109	* A structure like this will be allocated for each registered file system.	112	* A structure like this will be allocated for each registered file system.
110	*/	113	*/
111	typedef struct {	114	typedef struct {
112	link_t fs_link;	115	link_t fs_link;
113	vfs_info_t vfs_info;	116	vfs_info_t vfs_info;
114	fs_handle_t fs_handle;	117	fs_handle_t fs_handle;
115	futex_t phone_futex; /*< Phone serializing futex. /	118	futex_t phone_futex; /*< Phone serializing futex. /
116	ipcarg_t phone;	119	ipcarg_t phone;
117	} fs_info_t;	120	} fs_info_t;
118		121
119	/**	122	/**
120	* VFS_PAIR uniquely represents a file system instance.	123	* VFS_PAIR uniquely represents a file system instance.
121	*/	124	*/
122	#define VFS_PAIR \	125	#define VFS_PAIR \
123	fs_handle_t fs_handle; \	126	fs_handle_t fs_handle; \
124	dev_handle_t dev_handle;	127	dev_handle_t dev_handle;
125		128
126	/**	129	/**
127	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but	130	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
128	* doesn't contain any state. For a stateful structure, see vfs_node_t.	131	* doesn't contain any state. For a stateful structure, see vfs_node_t.
129	*	132	*
130	* @note fs_handle, dev_handle and index are meant to be returned in one	133	* @note fs_handle, dev_handle and index are meant to be returned in one
131	* IPC reply.	134	* IPC reply.
132	*/	135	*/
133	#define VFS_TRIPLET \	136	#define VFS_TRIPLET \
134	VFS_PAIR; \	137	VFS_PAIR; \
135	fs_index_t index;	138	fs_index_t index;
136		139
137	typedef struct {	140	typedef struct {
138	VFS_PAIR;	141	VFS_PAIR;
139	} vfs_pair_t;	142	} vfs_pair_t;
140		143
141	typedef struct {	144	typedef struct {
142	VFS_TRIPLET;	145	VFS_TRIPLET;
143	} vfs_triplet_t;	146	} vfs_triplet_t;
144		147
145	/*	148	/*
146	* Lookup flags.	149	* Lookup flags.
147	*/	150	*/
148	/**	151	/**
149	* No lookup flags used.	152	* No lookup flags used.
150	*/	153	*/
151	#define L_NONE 0	154	#define L_NONE 0
152	/**	155	/**
153	* Lookup will succeed only if the object is a regular file. If L_CREATE is	156	* Lookup will succeed only if the object is a regular file. If L_CREATE is
154	* specified, an empty file will be created. This flag is mutually exclusive	157	* specified, an empty file will be created. This flag is mutually exclusive
155	* with L_DIRECTORY.	158	* with L_DIRECTORY.
156	*/	159	*/
157	#define L_FILE 1	160	#define L_FILE 1
158	/**	161	/**
159	* Lookup wil succeed only if the object is a directory. If L_CREATE is	162	* Lookup wil succeed only if the object is a directory. If L_CREATE is
160	* specified, an empty directory will be created. This flag is mutually	163	* specified, an empty directory will be created. This flag is mutually
161	* exclusive with L_FILE.	164	* exclusive with L_FILE.
162	*/	165	*/
163	#define L_DIRECTORY 2	166	#define L_DIRECTORY 2
164	/**	167	/**
165	* When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the	168	* When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the
166	* object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.	169	* object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
167	*/	170	*/
168	#define L_EXCLUSIVE 4	171	#define L_EXCLUSIVE 4
169	/**	172	/**
170	* L_CREATE is used for creating both regular files and directories.	173	* L_CREATE is used for creating both regular files and directories.
171	*/	174	*/
172	#define L_CREATE 8	175	#define L_CREATE 8
173	/**	176	/**
174	* L_LINK is used for linking to an already existing nodes.	177	* L_LINK is used for linking to an already existing nodes.
175	*/	178	*/
176	#define L_LINK 16	179	#define L_LINK 16
177	/**	180	/**
178	* L_UNLINK is used to remove leaves from the file system namespace. This flag	181	* L_UNLINK is used to remove leaves from the file system namespace. This flag
179	* cannot be passed directly by the client, but will be set by VFS during	182	* cannot be passed directly by the client, but will be set by VFS during
180	* VFS_UNLINK.	183	* VFS_UNLINK.
181	*/	184	*/
182	#define L_UNLINK 32	185	#define L_UNLINK 32
183	/**	186	/**
184	* L_PARENT performs a lookup but returns the triplet of the parent node.	187	* L_PARENT performs a lookup but returns the triplet of the parent node.
185	* This flag may not be combined with any other lookup flag.	188	* This flag may not be combined with any other lookup flag.
186	*/	189	*/
187	#define L_PARENT 64	190	#define L_PARENT 64
188		191
189	typedef struct {	192	typedef struct {
190	vfs_triplet_t triplet;	193	vfs_triplet_t triplet;
191	size_t size;	194	size_t size;
192	unsigned lnkcnt;	195	unsigned lnkcnt;
193	} vfs_lookup_res_t;	196	} vfs_lookup_res_t;
194		197
195	/**	198	/**
196	* Instances of this type represent an active, in-memory VFS node and any state	199	* Instances of this type represent an active, in-memory VFS node and any state
197	* which may be associated with it.	200	* which may be associated with it.
198	*/	201	*/
199	typedef struct {	202	typedef struct {
200	VFS_TRIPLET; /*< Identity of the node. /	203	VFS_TRIPLET; /*< Identity of the node. /
201		204
202	/**	205	/**
203	* Usage counter. This includes, but is not limited to, all vfs_file_t	206	* Usage counter. This includes, but is not limited to, all vfs_file_t
204	* structures that reference this node.	207	* structures that reference this node.
205	*/	208	*/
206	unsigned refcnt;	209	unsigned refcnt;
207		210
208	/** Number of names this node has in the file system namespace. */	211	/** Number of names this node has in the file system namespace. */
209	unsigned lnkcnt;	212	unsigned lnkcnt;
210		213
211	link_t nh_link; /*< Node hash-table link. /	214	link_t nh_link; /*< Node hash-table link. /
212	size_t size; /*< Cached size if the node is a file. /	215	size_t size; /*< Cached size if the node is a file. /
213		216
214	/**	217	/**
215	* Holding this rwlock prevents modifications of the node's contents.	218	* Holding this rwlock prevents modifications of the node's contents.
216	*/	219	*/
217	rwlock_t contents_rwlock;	220	rwlock_t contents_rwlock;
218	} vfs_node_t;	221	} vfs_node_t;
219		222
220	/**	223	/**
221	* Instances of this type represent an open file. If the file is opened by more	224	* Instances of this type represent an open file. If the file is opened by more
222	* than one task, there will be a separate structure allocated for each task.	225	* than one task, there will be a separate structure allocated for each task.
223	*/	226	*/
224	typedef struct {	227	typedef struct {
225	/** Serializes access to this open file. */	228	/** Serializes access to this open file. */
226	futex_t lock;	229	futex_t lock;
227		230
228	vfs_node_t *node;	231	vfs_node_t *node;
229		232
230	/** Number of file handles referencing this file. */	233	/** Number of file handles referencing this file. */
231	unsigned refcnt;	234	unsigned refcnt;
232		235
233	/** Append on write. */	236	/** Append on write. */
234	bool append;	237	bool append;
235		238
236	/** Current position in the file. */	239	/** Current position in the file. */
237	off_t pos;	240	off_t pos;
238	} vfs_file_t;	241	} vfs_file_t;
239		242
240	extern futex_t nodes_futex;	243	extern futex_t nodes_futex;
241		244
242	extern link_t fs_head; /*< List of registered file systems. /	245	extern link_t fs_head; /*< List of registered file systems. /
243		246
244	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /	247	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /
245		248
246	#define MAX_PATH_LEN (64 * 1024)	249	#define MAX_PATH_LEN (64 * 1024)
247		250
248	#define PLB_SIZE (2 * MAX_PATH_LEN)	251	#define PLB_SIZE (2 * MAX_PATH_LEN)
249		252
250	/** Each instance of this type describes one path lookup in progress. */	253	/** Each instance of this type describes one path lookup in progress. */
251	typedef struct {	254	typedef struct {
252	link_t plb_link; /*< Active PLB entries list link. /	255	link_t plb_link; /*< Active PLB entries list link. /
253	unsigned index; /*< Index of the first character in PLB. /	256	unsigned index; /*< Index of the first character in PLB. /
254	size_t len; /*< Number of characters in this PLB entry. /	257	size_t len; /*< Number of characters in this PLB entry. /
255	} plb_entry_t;	258	} plb_entry_t;
256		259
257	extern futex_t plb_futex; /*< Futex protecting plb and plb_head. /	260	extern futex_t plb_futex; /*< Futex protecting plb and plb_head. /
258	extern uint8_t plb; /< Path Lookup Buffer /	261	extern uint8_t plb; /< Path Lookup Buffer /
259	extern link_t plb_head; /*< List of active PLB entries. /	262	extern link_t plb_head; /*< List of active PLB entries. /
260		263
261	/** Holding this rwlock prevents changes in file system namespace. */	264	/** Holding this rwlock prevents changes in file system namespace. */
262	extern rwlock_t namespace_rwlock;	265	extern rwlock_t namespace_rwlock;
263		266
264	extern int vfs_grab_phone(fs_handle_t);	267	extern int vfs_grab_phone(fs_handle_t);
265	extern void vfs_release_phone(int);	268	extern void vfs_release_phone(int);
266		269
267	extern fs_handle_t fs_name_to_handle(char *, bool);	270	extern fs_handle_t fs_name_to_handle(char *, bool);
268		271
269	extern int vfs_lookup_internal(char , int, vfs_lookup_res_t , vfs_pair_t *,	272	extern int vfs_lookup_internal(char , int, vfs_lookup_res_t , vfs_pair_t *,
270	...);	273	...);
271		274
272	extern bool vfs_nodes_init(void);	275	extern bool vfs_nodes_init(void);
273	extern vfs_node_t vfs_node_get(vfs_lookup_res_t );	276	extern vfs_node_t vfs_node_get(vfs_lookup_res_t );
274	extern void vfs_node_put(vfs_node_t *);	277	extern void vfs_node_put(vfs_node_t *);
275		278
276	#define MAX_OPEN_FILES 128	279	#define MAX_OPEN_FILES 128
277		280
278	extern bool vfs_files_init(void);	281	extern bool vfs_files_init(void);
279	extern vfs_file_t *vfs_file_get(int);	282	extern vfs_file_t *vfs_file_get(int);
280	extern int vfs_fd_alloc(void);	283	extern int vfs_fd_alloc(void);
281	extern void vfs_fd_free(int);	284	extern void vfs_fd_free(int);
282		285
283	extern void vfs_file_addref(vfs_file_t *);	286	extern void vfs_file_addref(vfs_file_t *);
284	extern void vfs_file_delref(vfs_file_t *);	287	extern void vfs_file_delref(vfs_file_t *);
285		288
286	extern void vfs_node_addref(vfs_node_t *);	289	extern void vfs_node_addref(vfs_node_t *);
287	extern void vfs_node_delref(vfs_node_t *);	290	extern void vfs_node_delref(vfs_node_t *);
288		291
289	extern void vfs_register(ipc_callid_t, ipc_call_t *);	292	extern void vfs_register(ipc_callid_t, ipc_call_t *);
290	extern void vfs_mount(ipc_callid_t, ipc_call_t *);	293	extern void vfs_mount(ipc_callid_t, ipc_call_t *);
291	extern void vfs_open(ipc_callid_t, ipc_call_t *);	294	extern void vfs_open(ipc_callid_t, ipc_call_t *);
292	extern void vfs_close(ipc_callid_t, ipc_call_t *);	295	extern void vfs_close(ipc_callid_t, ipc_call_t *);
293	extern void vfs_read(ipc_callid_t, ipc_call_t *);	296	extern void vfs_read(ipc_callid_t, ipc_call_t *);
294	extern void vfs_write(ipc_callid_t, ipc_call_t *);	297	extern void vfs_write(ipc_callid_t, ipc_call_t *);
295	extern void vfs_seek(ipc_callid_t, ipc_call_t *);	298	extern void vfs_seek(ipc_callid_t, ipc_call_t *);
296	extern void vfs_truncate(ipc_callid_t, ipc_call_t *);	299	extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
297	extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);	300	extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
298	extern void vfs_unlink(ipc_callid_t, ipc_call_t *);	301	extern void vfs_unlink(ipc_callid_t, ipc_call_t *);
299	extern void vfs_rename(ipc_callid_t, ipc_call_t *);	302	extern void vfs_rename(ipc_callid_t, ipc_call_t *);
300		303
301	#endif	304	#endif
302		305
303	/**	306	/**
304	* @}	307	* @}
305	*/	308	*/
306		309

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(root)/branches/dynload/uspace/srv/vfs/vfs.h – Rev 2927 → 3150