WebSVN – HelenOS – Diff – /branches/network/uspace/lib/libblock/libblock.h


/*
 * Copyright (c) 2008 Jakub Jermar
 * Copyright (c) 2008 Martin Decky
 * 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 libblock
 * @{
 */
/**
 * @file
 */
 
#ifndef LIBBLOCK_LIBBLOCK_H_
#define LIBBLOCK_LIBBLOCK_H_ 
 
#include <stdint.h>
#include "../../srv/vfs/vfs.h"
#include <fibril_sync.h>
#include <adt/hash_table.h>
#include <adt/list.h>
 
/*
 * Flags that can be used with block_get().
 */
 
/**
 * This macro is a symbolic value for situations where no special flags are
 * needed.
 */
#define BLOCK_FLAGS_NONE    0
 
/**
 * When the client of block_get() intends to overwrite the current contents of
 * the block, this flag is used to avoid the unnecessary read.
 */
#define BLOCK_FLAGS_NOREAD  1
 
typedef unsigned bn_t;  /**< Block number type. */
 
typedef struct block {
    /** Mutex protecting the reference count. */
    fibril_mutex_t lock;
    /** Number of references to the block_t structure. */
    unsigned refcnt;
    /** If true, the block needs to be written back to the block device. */
    bool dirty;
    /** Readers / Writer lock protecting the contents of the block. */
    fibril_rwlock_t contents_lock;
    /** Handle of the device where the block resides. */
    dev_handle_t dev_handle;
    /** Block offset on the block device. Counted in 'size'-byte blocks. */
    bn_t boff;
    /** Size of the block. */
    size_t size;
    /** Link for placing the block into the free block list. */
    link_t free_link;
    /** Link for placing the block into the block hash table. */
    link_t hash_link;
    /** Buffer with the block data. */
    void *data;
} block_t;
 
/** Caching mode */
enum cache_mode {
    /** Write-Through */
    CACHE_MODE_WT,
    /** Write-Back */
    CACHE_MODE_WB
};
 
extern int block_init(dev_handle_t, size_t);
extern void block_fini(dev_handle_t);
 
extern int block_bb_read(dev_handle_t, off_t, size_t);
extern void *block_bb_get(dev_handle_t);
 
extern int block_cache_init(dev_handle_t, size_t, unsigned, enum cache_mode);
 
extern block_t *block_get(dev_handle_t, bn_t, int);
extern void block_put(block_t *);
 
extern int block_seqread(dev_handle_t, off_t *, size_t *, off_t *, void *,
    size_t, size_t);
 
#endif
 
/** @}
 */
 
 

Rev 4581	Rev 4718
1	/*	1	/*
2	* Copyright (c) 2008 Jakub Jermar	2	* Copyright (c) 2008 Jakub Jermar
3	* Copyright (c) 2008 Martin Decky	3	* Copyright (c) 2008 Martin Decky
4	* All rights reserved.	4	* All rights reserved.
5	*	5	*
6	* Redistribution and use in source and binary forms, with or without	6	* Redistribution and use in source and binary forms, with or without
7	* modification, are permitted provided that the following conditions	7	* modification, are permitted provided that the following conditions
8	* are met:	8	* are met:
9	*	9	*
10	* - Redistributions of source code must retain the above copyright	10	* - Redistributions of source code must retain the above copyright
11	* notice, this list of conditions and the following disclaimer.	11	* notice, this list of conditions and the following disclaimer.
12	* - Redistributions in binary form must reproduce the above copyright	12	* - Redistributions in binary form must reproduce the above copyright
13	* notice, this list of conditions and the following disclaimer in the	13	* notice, this list of conditions and the following disclaimer in the
14	* documentation and/or other materials provided with the distribution.	14	* documentation and/or other materials provided with the distribution.
15	* - The name of the author may not be used to endorse or promote products	15	* - The name of the author may not be used to endorse or promote products
16	* derived from this software without specific prior written permission.	16	* derived from this software without specific prior written permission.
17	*	17	*
18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28	*/	28	*/
29		29
30	/** @addtogroup libblock	30	/** @addtogroup libblock
31	* @{	31	* @{
32	*/	32	*/
33	/**	33	/**
34	* @file	34	* @file
35	*/	35	*/
36		36
37	#ifndef LIBBLOCK_LIBBLOCK_H_	37	#ifndef LIBBLOCK_LIBBLOCK_H_
38	#define LIBBLOCK_LIBBLOCK_H_	38	#define LIBBLOCK_LIBBLOCK_H_
39		39
40	#include <stdint.h>	40	#include <stdint.h>
41	#include "../../srv/vfs/vfs.h"	41	#include "../../srv/vfs/vfs.h"
42	#include <fibril_sync.h>	42	#include <fibril_sync.h>
43	#include <adt/hash_table.h>	43	#include <adt/hash_table.h>
44	#include <adt/list.h>	44	#include <adt/list.h>
45		45
46	/*	46	/*
47	* Flags that can be used with block_get().	47	* Flags that can be used with block_get().
48	*/	48	*/
49		49
50	/**	50	/**
51	* This macro is a symbolic value for situations where no special flags are	51	* This macro is a symbolic value for situations where no special flags are
52	* needed.	52	* needed.
53	*/	53	*/
54	#define BLOCK_FLAGS_NONE 0	54	#define BLOCK_FLAGS_NONE 0
55		55
56	/**	56	/**
57	* When the client of block_get() intends to overwrite the current contents of	57	* When the client of block_get() intends to overwrite the current contents of
58	* the block, this flag is used to avoid the unnecessary read.	58	* the block, this flag is used to avoid the unnecessary read.
59	*/	59	*/
60	#define BLOCK_FLAGS_NOREAD 1	60	#define BLOCK_FLAGS_NOREAD 1
61		61
62	typedef unsigned bn_t; /*< Block number type. /	62	typedef unsigned bn_t; /*< Block number type. /
63		63
64	typedef struct block {	64	typedef struct block {
65	/** Mutex protecting the reference count. */	65	/** Mutex protecting the reference count. */
66	fibril_mutex_t lock;	66	fibril_mutex_t lock;
67	/** Number of references to the block_t structure. */	67	/** Number of references to the block_t structure. */
68	unsigned refcnt;	68	unsigned refcnt;
69	/** If true, the block needs to be written back to the block device. */	69	/** If true, the block needs to be written back to the block device. */
70	bool dirty;	70	bool dirty;
71	/** Readers / Writer lock protecting the contents of the block. */	71	/** Readers / Writer lock protecting the contents of the block. */
72	fibril_rwlock_t contents_lock;	72	fibril_rwlock_t contents_lock;
73	/** Handle of the device where the block resides. */	73	/** Handle of the device where the block resides. */
74	dev_handle_t dev_handle;	74	dev_handle_t dev_handle;
75	/** Block offset on the block device. Counted in 'size'-byte blocks. */	75	/** Block offset on the block device. Counted in 'size'-byte blocks. */
76	bn_t boff;	76	bn_t boff;
77	/** Size of the block. */	77	/** Size of the block. */
78	size_t size;	78	size_t size;
79	/** Link for placing the block into the free block list. */	79	/** Link for placing the block into the free block list. */
80	link_t free_link;	80	link_t free_link;
81	/** Link for placing the block into the block hash table. */	81	/** Link for placing the block into the block hash table. */
82	link_t hash_link;	82	link_t hash_link;
83	/** Buffer with the block data. */	83	/** Buffer with the block data. */
84	void *data;	84	void *data;
85	} block_t;	85	} block_t;
86		86
87	/** Caching mode */	87	/** Caching mode */
88	enum cache_mode {	88	enum cache_mode {
89	/** Write-Through */	89	/** Write-Through */
90	CACHE_MODE_WT,	90	CACHE_MODE_WT,
91	/** Write-Back */	91	/** Write-Back */
92	CACHE_MODE_WB	92	CACHE_MODE_WB
93	};	93	};
94		94
95	extern int block_init(dev_handle_t, size_t);	95	extern int block_init(dev_handle_t, size_t);
96	extern void block_fini(dev_handle_t);	96	extern void block_fini(dev_handle_t);
97		97
98	extern int block_bb_read(dev_handle_t, off_t, size_t);	98	extern int block_bb_read(dev_handle_t, off_t, size_t);
99	extern void *block_bb_get(dev_handle_t);	99	extern void *block_bb_get(dev_handle_t);
100		100
101	extern int block_cache_init(dev_handle_t, size_t, unsigned, enum cache_mode);	101	extern int block_cache_init(dev_handle_t, size_t, unsigned, enum cache_mode);
102		102
103	extern block_t *block_get(dev_handle_t, bn_t, int flags);	103	extern block_t *block_get(dev_handle_t, bn_t, int);
104	extern void block_put(block_t *);	104	extern void block_put(block_t *);
105		105
106	extern int block_read(dev_handle_t, off_t , size_t , off_t , void , size_t,	106	extern int block_seqread(dev_handle_t, off_t , size_t , off_t , void ,
107	size_t);	107	size_t, size_t);
108		108
109	#endif	109	#endif
110		110
111	/** @}	111	/** @}
112	*/	112	*/
113		113
114		114

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(root)/branches/network/uspace/lib/libblock/libblock.h – Rev 4581 → 4718