109 lines
2.4 KiB
C++
109 lines
2.4 KiB
C++
/*
|
|
* Copyright (c) 2013, 2014, 2015, 2022 Jonas 'Sortie' Termansen.
|
|
*
|
|
* Permission to use, copy, modify, and distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*
|
|
* block.cpp
|
|
* Blocks in the filesystem.
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
|
|
#include <assert.h>
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
#include "block.h"
|
|
#include "device.h"
|
|
#include "ioleast.h"
|
|
|
|
Block::Block()
|
|
{
|
|
this->block_data = NULL;
|
|
}
|
|
|
|
Block::Block(Device* device, uint32_t block_id)
|
|
{
|
|
Construct(device, block_id);
|
|
}
|
|
|
|
void Block::Construct(Device* device, uint32_t block_id)
|
|
{
|
|
this->prev_block = NULL;
|
|
this->next_block = NULL;
|
|
this->prev_hashed = NULL;
|
|
this->next_hashed = NULL;
|
|
this->device = device;
|
|
this->reference_count = 1;
|
|
this->block_id = block_id;
|
|
}
|
|
|
|
Block::~Block()
|
|
{
|
|
Destruct();
|
|
delete[] block_data;
|
|
}
|
|
|
|
void Block::Destruct()
|
|
{
|
|
Unlink();
|
|
}
|
|
|
|
void Block::Refer()
|
|
{
|
|
reference_count++;
|
|
}
|
|
|
|
void Block::Unref()
|
|
{
|
|
if ( !--reference_count )
|
|
{
|
|
#if 0
|
|
device->block_count--;
|
|
delete this;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
void Block::Use()
|
|
{
|
|
Unlink();
|
|
Prelink();
|
|
}
|
|
|
|
void Block::Unlink()
|
|
{
|
|
(prev_block ? prev_block->next_block : device->mru_block) = next_block;
|
|
(next_block ? next_block->prev_block : device->lru_block) = prev_block;
|
|
size_t bin = block_id % DEVICE_HASH_LENGTH;
|
|
(prev_hashed ? prev_hashed->next_hashed : device->hash_blocks[bin]) = next_hashed;
|
|
if ( next_hashed ) next_hashed->prev_hashed = prev_hashed;
|
|
}
|
|
|
|
void Block::Prelink()
|
|
{
|
|
prev_block = NULL;
|
|
next_block = device->mru_block;
|
|
if ( device->mru_block )
|
|
device->mru_block->prev_block = this;
|
|
device->mru_block = this;
|
|
if ( !device->lru_block )
|
|
device->lru_block = this;
|
|
size_t bin = block_id % DEVICE_HASH_LENGTH;
|
|
prev_hashed = NULL;
|
|
next_hashed = device->hash_blocks[bin];
|
|
device->hash_blocks[bin] = this;
|
|
if ( next_hashed )
|
|
next_hashed->prev_hashed = this;
|
|
}
|