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* Copyright (c) 2008 Jakub Jermar
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* Copyright (c) 2008 Martin Decky
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* - Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* - Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* - The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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/** @addtogroup libblock
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#ifndef LIBBLOCK_LIBBLOCK_H_
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#define LIBBLOCK_LIBBLOCK_H_
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#include "../../srv/vfs/vfs.h"
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#include <fibril_sync.h>
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#include <adt/hash_table.h>
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* Flags that can be used with block_get().
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* This macro is a symbolic value for situations where no special flags are
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#define BLOCK_FLAGS_NONE 0
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* When the client of block_get() intends to overwrite the current contents of
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* the block, this flag is used to avoid the unnecessary read.
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#define BLOCK_FLAGS_NOREAD 1
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typedef unsigned bn_t; /**< Block number type. */
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typedef struct block {
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/** Mutex protecting the reference count. */
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/** Number of references to the block_t structure. */
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/** If true, the block needs to be written back to the block device. */
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/** Readers / Writer lock protecting the contents of the block. */
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fibril_rwlock_t contents_lock;
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/** Handle of the device where the block resides. */
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dev_handle_t dev_handle;
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/** Block offset on the block device. Counted in 'size'-byte blocks. */
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/** Size of the block. */
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/** Link for placing the block into the free block list. */
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/** Link for placing the block into the block hash table. */
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/** Buffer with the block data. */
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extern int block_init(dev_handle_t, size_t);
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extern void block_fini(dev_handle_t);
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extern int block_bb_read(dev_handle_t, off_t, size_t);
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extern void *block_bb_get(dev_handle_t);
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extern int block_cache_init(dev_handle_t, size_t, unsigned, enum cache_mode);
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extern block_t *block_get(dev_handle_t, bn_t, int);
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extern void block_put(block_t *);
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extern int block_seqread(dev_handle_t, off_t *, size_t *, off_t *, void *,