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

Rev	Author	Line No.	Line
2520	jermar	1	/*
		2	* Copyright (c) 2007 Jakub Jermar
		3	* All rights reserved.
		4	*
		5	* Redistribution and use in source and binary forms, with or without
		6	* modification, are permitted provided that the following conditions
		7	* are met:
		8	*
		9	* - Redistributions of source code must retain the above copyright
		10	* notice, this list of conditions and the following disclaimer.
		11	* - Redistributions in binary form must reproduce the above copyright
		12	* notice, this list of conditions and the following disclaimer in the
		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
		15	* derived from this software without specific prior written permission.
		16	*
		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
		19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
		20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
		21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
		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
		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
		26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
		27	*/
		28
		29	/** @addtogroup fs
		30	* @{
		31	*/
		32
		33	#ifndef VFS_VFS_H_
		34	#define VFS_VFS_H_
		35
2523	jermar	36	#include <ipc/ipc.h>
2529	jermar	37	#include <libadt/list.h>
2540	jermar	38	#include <atomic.h>
2542	jermar	39	#include <sys/types.h>
2523	jermar	40
2535	jermar	41	#define dprintf(...) printf(__VA_ARGS__)
		42
2523	jermar	43	#define VFS_FIRST FIRST_USER_METHOD
		44
2526	jermar	45	#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)
		46
2520	jermar	47	typedef enum {
2523	jermar	48	VFS_REGISTER = VFS_FIRST,
2520	jermar	49	VFS_MOUNT,
		50	VFS_UNMOUNT,
2527	jermar	51	VFS_LOOKUP,
2521	jermar	52	VFS_OPEN,
2523	jermar	53	VFS_CREATE,
		54	VFS_CLOSE,
		55	VFS_READ,
		56	VFS_WRITE,
		57	VFS_SEEK,
2521	jermar	58	VFS_LAST, /* keep this the last member of the enum */
2520	jermar	59	} vfs_request_t;
		60
2521	jermar	61
		62	/**
		63	* An instance of this structure is associated with a particular FS operation.
		64	* It tells VFS if the FS supports the operation or maybe if a default one
		65	* should be used.
		66	*/
		67	typedef enum {
2523	jermar	68	VFS_OP_NULL = 0,
2521	jermar	69	VFS_OP_DEFAULT,
		70	VFS_OP_DEFINED
		71	} vfs_op_t;
		72
		73	#define FS_NAME_MAXLEN 20
		74
		75	/**
		76	* A structure like this is passed to VFS by each individual FS upon its
		77	* registration. It assosiates a human-readable identifier with each
		78	* registered FS. More importantly, through this structure, the FS announces
		79	* what operations it supports.
		80	*/
		81	typedef struct {
2523	jermar	82	/** Unique identifier of the fs. */
2526	jermar	83	char name[FS_NAME_MAXLEN];
2523	jermar	84
		85	/** Operations. */
		86	vfs_op_t ops[VFS_LAST - VFS_FIRST];
2521	jermar	87	} vfs_info_t;
		88
2540	jermar	89	/**
		90	* A structure like this will be allocated for each registered file system.
		91	*/
2526	jermar	92	typedef struct {
		93	link_t fs_link;
		94	vfs_info_t vfs_info;
2546	jermar	95	int fs_handle;
		96	atomic_t phone_futex; /*< Phone serializing futex. /
2527	jermar	97	ipcarg_t phone;
2526	jermar	98	} fs_info_t;
		99
2540	jermar	100	/**
		101	* Instances of this type represent a file system node (e.g. directory, file).
		102	* They are abstracted away from any file system implementation and contain just
		103	* enough bits to uniquely identify the object in its file system instance.
		104	*
		105	* @note fs_handle, dev_handle and index are meant to be returned in one
		106	* IPC reply.
		107	*/
		108	typedef struct {
		109	int fs_handle; /*< Global file system ID. /
		110	int dev_handle; /*< Global mount device devno. /
		111	uint64_t index; /*< Index of the node on its file system. /
		112	} vfs_node_t;
		113
		114	/**
		115	* Instances of this type represent an open file. If the file is opened by more
		116	* than one task, there will be a separate structure allocated for each task.
		117	*/
		118	typedef struct {
		119	vfs_node_t *node;
		120
		121	/** Number of file handles referencing this file. */
		122	atomic_t refcnt;
		123
		124	/** Current position in the file. */
		125	off_t pos;
		126	} vfs_file_t;
		127
2542	jermar	128	extern link_t fs_head; /*< List of registered file systems. /
2535	jermar	129
2542	jermar	130	extern vfs_node_t rootfs; /< Root node of the root file system. /
2535	jermar	131
2542	jermar	132	#define MAX_PATH_LEN (64 * 1024)
		133
		134	#define PLB_SIZE (2 * MAX_PATH_LEN)
		135
		136	/** Each instance of this type describes one path lookup in progress. */
		137	typedef struct {
		138	link_t plb_link; /*< Active PLB entries list link. /
		139	unsigned index; /*< Index of the first character in PLB. /
		140	size_t len; /*< Number of characters in this PLB entry. /
		141	} plb_entry_t;
		142
		143	extern atomic_t plb_futex; /*< Futex protecting plb and plb_head. /
		144	extern uint8_t plb; /< Path Lookup Buffer /
		145	extern link_t plb_head; /*< List of active PLB entries. /
		146
2546	jermar	147	extern int vfs_grab_phone(int);
		148	extern void vfs_release_phone(int);
		149
2548	jermar	150	extern int fs_name_to_handle(char *name, bool lock);
		151
2549	jermar	152	extern int vfs_lookup_internal(char path, size_t len, vfs_node_t result,
		153	vfs_node_t *altroot);
2544	jermar	154
2542	jermar	155	extern void vfs_register(ipc_callid_t, ipc_call_t *);
2544	jermar	156	extern void vfs_mount(ipc_callid_t, ipc_call_t *);
2542	jermar	157
2520	jermar	158	#endif
		159
		160	/**
		161	* @}
2523	jermar	162	*/

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/vfs/vfs.h @ 4682 – Rev 2549