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>
 
#define dprintf(...)    printf(__VA_ARGS__)
 
#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 2770	Rev 2821
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	#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	/* Basic types. */	49	/* Basic types. */
50	typedef int16_t fs_handle_t;	50	typedef int16_t fs_handle_t;
51	typedef int16_t dev_handle_t;	51	typedef int16_t dev_handle_t;
52	typedef uint32_t fs_index_t;	52	typedef uint32_t fs_index_t;
53		53
54	typedef enum {	54	typedef enum {
55	VFS_READ = VFS_FIRST,	55	VFS_READ = VFS_FIRST,
56	VFS_WRITE,	56	VFS_WRITE,
57	VFS_TRUNCATE,	57	VFS_TRUNCATE,
58	VFS_MOUNT,	58	VFS_MOUNT,
59	VFS_UNMOUNT,	59	VFS_UNMOUNT,
60	VFS_LAST_CMN, /* keep this the last member of this enum */	60	VFS_LAST_CMN, /* keep this the last member of this enum */
61	} vfs_request_cmn_t;	61	} vfs_request_cmn_t;
62		62
63	typedef enum {	63	typedef enum {
64	VFS_LOOKUP = VFS_LAST_CMN,	64	VFS_LOOKUP = VFS_LAST_CMN,
65	VFS_DESTROY,	65	VFS_DESTROY,
66	VFS_LAST_CLNT, /* keep this the last member of this enum */	66	VFS_LAST_CLNT, /* keep this the last member of this enum */
67	} vfs_request_clnt_t;	67	} vfs_request_clnt_t;
68		68
69	typedef enum {	69	typedef enum {
70	VFS_REGISTER = VFS_LAST_CMN,	70	VFS_REGISTER = VFS_LAST_CMN,
71	VFS_OPEN,	71	VFS_OPEN,
72	VFS_CLOSE,	72	VFS_CLOSE,
73	VFS_SEEK,	73	VFS_SEEK,
74	VFS_MKDIR,	74	VFS_MKDIR,
75	VFS_UNLINK,	75	VFS_UNLINK,
76	VFS_RENAME,	76	VFS_RENAME,
77	VFS_LAST_SRV, /* keep this the last member of this enum */	77	VFS_LAST_SRV, /* keep this the last member of this enum */
78	} vfs_request_srv_t;	78	} vfs_request_srv_t;
79		79
80		80
81	/**	81	/**
82	* An instance of this structure is associated with a particular FS operation.	82	* 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	83	* It tells VFS if the FS supports the operation or maybe if a default one
84	* should be used.	84	* should be used.
85	*/	85	*/
86	typedef enum {	86	typedef enum {
87	VFS_OP_NULL = 0,	87	VFS_OP_NULL = 0,
88	VFS_OP_DEFAULT,	88	VFS_OP_DEFAULT,
89	VFS_OP_DEFINED	89	VFS_OP_DEFINED
90	} vfs_op_t;	90	} vfs_op_t;
91		91
92	#define FS_NAME_MAXLEN 20	92	#define FS_NAME_MAXLEN 20
93		93
94	/**	94	/**
95	* A structure like this is passed to VFS by each individual FS upon its	95	* A structure like this is passed to VFS by each individual FS upon its
96	* registration. It assosiates a human-readable identifier with each	96	* registration. It assosiates a human-readable identifier with each
97	* registered FS. More importantly, through this structure, the FS announces	97	* registered FS. More importantly, through this structure, the FS announces
98	* what operations it supports.	98	* what operations it supports.
99	*/	99	*/
100	typedef struct {	100	typedef struct {
101	/** Unique identifier of the fs. */	101	/** Unique identifier of the fs. */
102	char name[FS_NAME_MAXLEN + 1];	102	char name[FS_NAME_MAXLEN + 1];
103		103
104	/** Operations. */	104	/** Operations. */
105	vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];	105	vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];
106	} vfs_info_t;	106	} vfs_info_t;
107		107
108	/**	108	/**
109	* A structure like this will be allocated for each registered file system.	109	* A structure like this will be allocated for each registered file system.
110	*/	110	*/
111	typedef struct {	111	typedef struct {
112	link_t fs_link;	112	link_t fs_link;
113	vfs_info_t vfs_info;	113	vfs_info_t vfs_info;
114	fs_handle_t fs_handle;	114	fs_handle_t fs_handle;
115	futex_t phone_futex; /*< Phone serializing futex. /	115	futex_t phone_futex; /*< Phone serializing futex. /
116	ipcarg_t phone;	116	ipcarg_t phone;
117	} fs_info_t;	117	} fs_info_t;
118		118
119	/**	119	/**
120	* VFS_PAIR uniquely represents a file system instance.	120	* VFS_PAIR uniquely represents a file system instance.
121	*/	121	*/
122	#define VFS_PAIR \	122	#define VFS_PAIR \
123	fs_handle_t fs_handle; \	123	fs_handle_t fs_handle; \
124	dev_handle_t dev_handle;	124	dev_handle_t dev_handle;
125		125
126	/**	126	/**
127	* VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but	127	* 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.	128	* doesn't contain any state. For a stateful structure, see vfs_node_t.
129	*	129	*
130	* @note fs_handle, dev_handle and index are meant to be returned in one	130	* @note fs_handle, dev_handle and index are meant to be returned in one
131	* IPC reply.	131	* IPC reply.
132	*/	132	*/
133	#define VFS_TRIPLET \	133	#define VFS_TRIPLET \
134	VFS_PAIR; \	134	VFS_PAIR; \
135	fs_index_t index;	135	fs_index_t index;
136		136
137	typedef struct {	137	typedef struct {
138	VFS_PAIR;	138	VFS_PAIR;
139	} vfs_pair_t;	139	} vfs_pair_t;
140		140
141	typedef struct {	141	typedef struct {
142	VFS_TRIPLET;	142	VFS_TRIPLET;
143	} vfs_triplet_t;	143	} vfs_triplet_t;
144		144
145	/*	145	/*
146	* Lookup flags.	146	* Lookup flags.
147	*/	147	*/
148	/**	148	/**
149	* No lookup flags used.	149	* No lookup flags used.
150	*/	150	*/
151	#define L_NONE 0	151	#define L_NONE 0
152	/**	152	/**
153	* Lookup will succeed only if the object is a regular file. If L_CREATE is	153	* 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	154	* specified, an empty file will be created. This flag is mutually exclusive
155	* with L_DIRECTORY.	155	* with L_DIRECTORY.
156	*/	156	*/
157	#define L_FILE 1	157	#define L_FILE 1
158	/**	158	/**
159	* Lookup wil succeed only if the object is a directory. If L_CREATE is	159	* 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	160	* specified, an empty directory will be created. This flag is mutually
161	* exclusive with L_FILE.	161	* exclusive with L_FILE.
162	*/	162	*/
163	#define L_DIRECTORY 2	163	#define L_DIRECTORY 2
164	/**	164	/**
165	* When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the	165	* 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.	166	* object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
167	*/	167	*/
168	#define L_EXCLUSIVE 4	168	#define L_EXCLUSIVE 4
169	/**	169	/**
170	* L_CREATE is used for creating both regular files and directories.	170	* L_CREATE is used for creating both regular files and directories.
171	*/	171	*/
172	#define L_CREATE 8	172	#define L_CREATE 8
173	/**	173	/**
174	* L_LINK is used for linking to an already existing nodes.	174	* L_LINK is used for linking to an already existing nodes.
175	*/	175	*/
176	#define L_LINK 16	176	#define L_LINK 16
177	/**	177	/**
178	* L_UNLINK is used to remove leaves from the file system namespace. This flag	178	* 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	179	* cannot be passed directly by the client, but will be set by VFS during
180	* VFS_UNLINK.	180	* VFS_UNLINK.
181	*/	181	*/
182	#define L_UNLINK 32	182	#define L_UNLINK 32
183	/**	183	/**
184	* L_PARENT performs a lookup but returns the triplet of the parent node.	184	* 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.	185	* This flag may not be combined with any other lookup flag.
186	*/	186	*/
187	#define L_PARENT 64	187	#define L_PARENT 64
188		188
189	typedef struct {	189	typedef struct {
190	vfs_triplet_t triplet;	190	vfs_triplet_t triplet;
191	size_t size;	191	size_t size;
192	unsigned lnkcnt;	192	unsigned lnkcnt;
193	} vfs_lookup_res_t;	193	} vfs_lookup_res_t;
194		194
195	/**	195	/**
196	* Instances of this type represent an active, in-memory VFS node and any state	196	* Instances of this type represent an active, in-memory VFS node and any state
197	* which may be associated with it.	197	* which may be associated with it.
198	*/	198	*/
199	typedef struct {	199	typedef struct {
200	VFS_TRIPLET; /*< Identity of the node. /	200	VFS_TRIPLET; /*< Identity of the node. /
201		201
202	/**	202	/**
203	* Usage counter. This includes, but is not limited to, all vfs_file_t	203	* Usage counter. This includes, but is not limited to, all vfs_file_t
204	* structures that reference this node.	204	* structures that reference this node.
205	*/	205	*/
206	unsigned refcnt;	206	unsigned refcnt;
207		207
208	/** Number of names this node has in the file system namespace. */	208	/** Number of names this node has in the file system namespace. */
209	unsigned lnkcnt;	209	unsigned lnkcnt;
210		210
211	link_t nh_link; /*< Node hash-table link. /	211	link_t nh_link; /*< Node hash-table link. /
212	size_t size; /*< Cached size of the file. /	212	size_t size; /*< Cached size if the node is a file. /
213		213
214	/**	214	/**
215	* Holding this rwlock prevents modifications of the node's contents.	215	* Holding this rwlock prevents modifications of the node's contents.
216	*/	216	*/
217	rwlock_t contents_rwlock;	217	rwlock_t contents_rwlock;
218	} vfs_node_t;	218	} vfs_node_t;
219		219
220	/**	220	/**
221	* Instances of this type represent an open file. If the file is opened by more	221	* 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.	222	* than one task, there will be a separate structure allocated for each task.
223	*/	223	*/
224	typedef struct {	224	typedef struct {
225	/** Serializes access to this open file. */	225	/** Serializes access to this open file. */
226	futex_t lock;	226	futex_t lock;
227		227
228	vfs_node_t *node;	228	vfs_node_t *node;
229		229
230	/** Number of file handles referencing this file. */	230	/** Number of file handles referencing this file. */
231	unsigned refcnt;	231	unsigned refcnt;
232		232
233	/** Append on write. */	233	/** Append on write. */
234	bool append;	234	bool append;
235		235
236	/** Current position in the file. */	236	/** Current position in the file. */
237	off_t pos;	237	off_t pos;
238	} vfs_file_t;	238	} vfs_file_t;
239		239
240	extern futex_t nodes_futex;	240	extern futex_t nodes_futex;
241		241
242	extern link_t fs_head; /*< List of registered file systems. /	242	extern link_t fs_head; /*< List of registered file systems. /
243		243
244	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /	244	extern vfs_triplet_t rootfs; /*< Root node of the root file system. /
245		245
246	#define MAX_PATH_LEN (64 * 1024)	246	#define MAX_PATH_LEN (64 * 1024)
247		247
248	#define PLB_SIZE (2 * MAX_PATH_LEN)	248	#define PLB_SIZE (2 * MAX_PATH_LEN)
249		249
250	/** Each instance of this type describes one path lookup in progress. */	250	/** Each instance of this type describes one path lookup in progress. */
251	typedef struct {	251	typedef struct {
252	link_t plb_link; /*< Active PLB entries list link. /	252	link_t plb_link; /*< Active PLB entries list link. /
253	unsigned index; /*< Index of the first character in PLB. /	253	unsigned index; /*< Index of the first character in PLB. /
254	size_t len; /*< Number of characters in this PLB entry. /	254	size_t len; /*< Number of characters in this PLB entry. /
255	} plb_entry_t;	255	} plb_entry_t;
256		256
257	extern futex_t plb_futex; /*< Futex protecting plb and plb_head. /	257	extern futex_t plb_futex; /*< Futex protecting plb and plb_head. /
258	extern uint8_t plb; /< Path Lookup Buffer /	258	extern uint8_t plb; /< Path Lookup Buffer /
259	extern link_t plb_head; /*< List of active PLB entries. /	259	extern link_t plb_head; /*< List of active PLB entries. /
260		260
261	/** Holding this rwlock prevents changes in file system namespace. */	261	/** Holding this rwlock prevents changes in file system namespace. */
262	extern rwlock_t namespace_rwlock;	262	extern rwlock_t namespace_rwlock;
263		263
264	extern int vfs_grab_phone(fs_handle_t);	264	extern int vfs_grab_phone(fs_handle_t);
265	extern void vfs_release_phone(int);	265	extern void vfs_release_phone(int);
266		266
267	extern fs_handle_t fs_name_to_handle(char *, bool);	267	extern fs_handle_t fs_name_to_handle(char *, bool);
268		268
269	extern int vfs_lookup_internal(char , int, vfs_lookup_res_t , vfs_pair_t *,	269	extern int vfs_lookup_internal(char , int, vfs_lookup_res_t , vfs_pair_t *,
270	...);	270	...);
271		271
272	extern bool vfs_nodes_init(void);	272	extern bool vfs_nodes_init(void);
273	extern vfs_node_t vfs_node_get(vfs_lookup_res_t );	273	extern vfs_node_t vfs_node_get(vfs_lookup_res_t );
274	extern void vfs_node_put(vfs_node_t *);	274	extern void vfs_node_put(vfs_node_t *);
275		275
276	#define MAX_OPEN_FILES 128	276	#define MAX_OPEN_FILES 128
277		277
278	extern bool vfs_files_init(void);	278	extern bool vfs_files_init(void);
279	extern vfs_file_t *vfs_file_get(int);	279	extern vfs_file_t *vfs_file_get(int);
280	extern int vfs_fd_alloc(void);	280	extern int vfs_fd_alloc(void);
281	extern void vfs_fd_free(int);	281	extern void vfs_fd_free(int);
282		282
283	extern void vfs_file_addref(vfs_file_t *);	283	extern void vfs_file_addref(vfs_file_t *);
284	extern void vfs_file_delref(vfs_file_t *);	284	extern void vfs_file_delref(vfs_file_t *);
285		285
286	extern void vfs_node_addref(vfs_node_t *);	286	extern void vfs_node_addref(vfs_node_t *);
287	extern void vfs_node_delref(vfs_node_t *);	287	extern void vfs_node_delref(vfs_node_t *);
288		288
289	extern void vfs_register(ipc_callid_t, ipc_call_t *);	289	extern void vfs_register(ipc_callid_t, ipc_call_t *);
290	extern void vfs_mount(ipc_callid_t, ipc_call_t *);	290	extern void vfs_mount(ipc_callid_t, ipc_call_t *);
291	extern void vfs_open(ipc_callid_t, ipc_call_t *);	291	extern void vfs_open(ipc_callid_t, ipc_call_t *);
292	extern void vfs_close(ipc_callid_t, ipc_call_t *);	292	extern void vfs_close(ipc_callid_t, ipc_call_t *);
293	extern void vfs_read(ipc_callid_t, ipc_call_t *);	293	extern void vfs_read(ipc_callid_t, ipc_call_t *);
294	extern void vfs_write(ipc_callid_t, ipc_call_t *);	294	extern void vfs_write(ipc_callid_t, ipc_call_t *);
295	extern void vfs_seek(ipc_callid_t, ipc_call_t *);	295	extern void vfs_seek(ipc_callid_t, ipc_call_t *);
296	extern void vfs_truncate(ipc_callid_t, ipc_call_t *);	296	extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
297	extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);	297	extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
298	extern void vfs_unlink(ipc_callid_t, ipc_call_t *);	298	extern void vfs_unlink(ipc_callid_t, ipc_call_t *);
299	extern void vfs_rename(ipc_callid_t, ipc_call_t *);	299	extern void vfs_rename(ipc_callid_t, ipc_call_t *);
300		300
301	#endif	301	#endif
302		302
303	/**	303	/**
304	* @}	304	* @}
305	*/	305	*/
306		306

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/vfs/vfs.h @ 2770 – Rev 2770 → 2821