btrfs-progs/extent-cache.h
Miao Xie 17793e3e6a Btrfs-progs: extend the extent cache for the device extent
As we know, btrfs can manage several devices in the same fs, so [offset, size]
is not sufficient for unique identification of an device extent, we need the
device id to identify the device extents which have the same offset and size,
but are not in the same device. So, we added a member variant named objectid
into the extent cache, and introduced some functions to make the extent cache
be suitable to manage the device extent.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-07-03 14:06:54 -04:00

82 lines
2.5 KiB
C

/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef __EXTENT_CACHE_H__
#define __EXTENT_CACHE_H__
#if BTRFS_FLAT_INCLUDES
#include "kerncompat.h"
#include "rbtree.h"
#else
#include <btrfs/kerncompat.h>
#include <btrfs/rbtree.h>
#endif /* BTRFS_FLAT_INCLUDES */
struct cache_tree {
struct rb_root root;
};
struct cache_extent {
struct rb_node rb_node;
u64 objectid;
u64 start;
u64 size;
};
void cache_tree_init(struct cache_tree *tree);
struct cache_extent *first_cache_extent(struct cache_tree *tree);
struct cache_extent *prev_cache_extent(struct cache_extent *pe);
struct cache_extent *next_cache_extent(struct cache_extent *pe);
struct cache_extent *search_cache_extent(struct cache_tree *tree, u64 start);
struct cache_extent *lookup_cache_extent(struct cache_tree *tree,
u64 start, u64 size);
int add_cache_extent(struct cache_tree *tree, u64 start, u64 size);
int insert_cache_extent(struct cache_tree *tree, struct cache_extent *pe);
void remove_cache_extent(struct cache_tree *tree, struct cache_extent *pe);
static inline int cache_tree_empty(struct cache_tree *tree)
{
return RB_EMPTY_ROOT(&tree->root);
}
typedef void (*free_cache_extent)(struct cache_extent *pe);
void cache_tree_free_extents(struct cache_tree *tree,
free_cache_extent free_func);
#define FREE_EXTENT_CACHE_BASED_TREE(name, free_func) \
static void free_##name##_tree(struct cache_tree *tree) \
{ \
cache_tree_free_extents(tree, free_func); \
}
void free_extent_cache_tree(struct cache_tree *tree);
struct cache_extent *search_cache_extent2(struct cache_tree *tree,
u64 objectid, u64 start);
struct cache_extent *lookup_cache_extent2(struct cache_tree *tree,
u64 objectid, u64 start, u64 size);
int add_cache_extent2(struct cache_tree *tree,
u64 objectid, u64 start, u64 size);
int insert_cache_extent2(struct cache_tree *tree, struct cache_extent *pe);
#endif