fs: btrfs: Crossport extent-cache.[ch] from btrfs-progs
This patch implements an infrastructure to insert/search/merge an extent range (with variable length). This provides the basis for later extent buffer cache used in btrfs. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Marek Behún <marek.behun@nic.cz>
This commit is contained in:
Qu Wenruo
Tom Rini
parent
bc621e545b
commit
ab5c3046f2
318
fs/btrfs/extent-cache.c
Normal file
318
fs/btrfs/extent-cache.c
Normal file
@ -0,0 +1,318 @@
|
||||
// SPDX-License-Identifier: GPL-2.0+
|
||||
|
||||
/*
|
||||
* Crossported from the same named file of btrfs-progs.
|
||||
*
|
||||
* Minor modification to include headers.
|
||||
*/
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/rbtree.h>
|
||||
#include <linux/errno.h>
|
||||
#include <linux/bug.h>
|
||||
#include <stdlib.h>
|
||||
#include "extent-cache.h"
|
||||
#include "common/rbtree-utils.h"
|
||||
|
||||
struct cache_extent_search_range {
|
||||
u64 objectid;
|
||||
u64 start;
|
||||
u64 size;
|
||||
};
|
||||
|
||||
static int cache_tree_comp_range(struct rb_node *node, void *data)
|
||||
{
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range *range;
|
||||
|
||||
range = (struct cache_extent_search_range *)data;
|
||||
entry = rb_entry(node, struct cache_extent, rb_node);
|
||||
|
||||
if (entry->start + entry->size <= range->start)
|
||||
return 1;
|
||||
else if (range->start + range->size <= entry->start)
|
||||
return -1;
|
||||
else
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int cache_tree_comp_nodes(struct rb_node *node1, struct rb_node *node2)
|
||||
{
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range range;
|
||||
|
||||
entry = rb_entry(node2, struct cache_extent, rb_node);
|
||||
range.start = entry->start;
|
||||
range.size = entry->size;
|
||||
|
||||
return cache_tree_comp_range(node1, (void *)&range);
|
||||
}
|
||||
|
||||
static int cache_tree_comp_range2(struct rb_node *node, void *data)
|
||||
{
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range *range;
|
||||
|
||||
range = (struct cache_extent_search_range *)data;
|
||||
entry = rb_entry(node, struct cache_extent, rb_node);
|
||||
|
||||
if (entry->objectid < range->objectid)
|
||||
return 1;
|
||||
else if (entry->objectid > range->objectid)
|
||||
return -1;
|
||||
else if (entry->start + entry->size <= range->start)
|
||||
return 1;
|
||||
else if (range->start + range->size <= entry->start)
|
||||
return -1;
|
||||
else
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int cache_tree_comp_nodes2(struct rb_node *node1, struct rb_node *node2)
|
||||
{
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range range;
|
||||
|
||||
entry = rb_entry(node2, struct cache_extent, rb_node);
|
||||
range.objectid = entry->objectid;
|
||||
range.start = entry->start;
|
||||
range.size = entry->size;
|
||||
|
||||
return cache_tree_comp_range2(node1, (void *)&range);
|
||||
}
|
||||
|
||||
void cache_tree_init(struct cache_tree *tree)
|
||||
{
|
||||
tree->root = RB_ROOT;
|
||||
}
|
||||
|
||||
static struct cache_extent *alloc_cache_extent(u64 start, u64 size)
|
||||
{
|
||||
struct cache_extent *pe = malloc(sizeof(*pe));
|
||||
|
||||
if (!pe)
|
||||
return pe;
|
||||
|
||||
pe->objectid = 0;
|
||||
pe->start = start;
|
||||
pe->size = size;
|
||||
return pe;
|
||||
}
|
||||
|
||||
int add_cache_extent(struct cache_tree *tree, u64 start, u64 size)
|
||||
{
|
||||
struct cache_extent *pe = alloc_cache_extent(start, size);
|
||||
int ret;
|
||||
|
||||
if (!pe)
|
||||
return -ENOMEM;
|
||||
|
||||
ret = insert_cache_extent(tree, pe);
|
||||
if (ret)
|
||||
free(pe);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
int insert_cache_extent(struct cache_tree *tree, struct cache_extent *pe)
|
||||
{
|
||||
return rb_insert(&tree->root, &pe->rb_node, cache_tree_comp_nodes);
|
||||
}
|
||||
|
||||
int insert_cache_extent2(struct cache_tree *tree, struct cache_extent *pe)
|
||||
{
|
||||
return rb_insert(&tree->root, &pe->rb_node, cache_tree_comp_nodes2);
|
||||
}
|
||||
|
||||
struct cache_extent *lookup_cache_extent(struct cache_tree *tree,
|
||||
u64 start, u64 size)
|
||||
{
|
||||
struct rb_node *node;
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range range;
|
||||
|
||||
range.start = start;
|
||||
range.size = size;
|
||||
node = rb_search(&tree->root, &range, cache_tree_comp_range, NULL);
|
||||
if (!node)
|
||||
return NULL;
|
||||
|
||||
entry = rb_entry(node, struct cache_extent, rb_node);
|
||||
return entry;
|
||||
}
|
||||
|
||||
struct cache_extent *lookup_cache_extent2(struct cache_tree *tree,
|
||||
u64 objectid, u64 start, u64 size)
|
||||
{
|
||||
struct rb_node *node;
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range range;
|
||||
|
||||
range.objectid = objectid;
|
||||
range.start = start;
|
||||
range.size = size;
|
||||
node = rb_search(&tree->root, &range, cache_tree_comp_range2, NULL);
|
||||
if (!node)
|
||||
return NULL;
|
||||
|
||||
entry = rb_entry(node, struct cache_extent, rb_node);
|
||||
return entry;
|
||||
}
|
||||
|
||||
struct cache_extent *search_cache_extent(struct cache_tree *tree, u64 start)
|
||||
{
|
||||
struct rb_node *next;
|
||||
struct rb_node *node;
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range range;
|
||||
|
||||
range.start = start;
|
||||
range.size = 1;
|
||||
node = rb_search(&tree->root, &range, cache_tree_comp_range, &next);
|
||||
if (!node)
|
||||
node = next;
|
||||
if (!node)
|
||||
return NULL;
|
||||
|
||||
entry = rb_entry(node, struct cache_extent, rb_node);
|
||||
return entry;
|
||||
}
|
||||
|
||||
struct cache_extent *search_cache_extent2(struct cache_tree *tree,
|
||||
u64 objectid, u64 start)
|
||||
{
|
||||
struct rb_node *next;
|
||||
struct rb_node *node;
|
||||
struct cache_extent *entry;
|
||||
struct cache_extent_search_range range;
|
||||
|
||||
range.objectid = objectid;
|
||||
range.start = start;
|
||||
range.size = 1;
|
||||
node = rb_search(&tree->root, &range, cache_tree_comp_range2, &next);
|
||||
if (!node)
|
||||
node = next;
|
||||
if (!node)
|
||||
return NULL;
|
||||
|
||||
entry = rb_entry(node, struct cache_extent, rb_node);
|
||||
return entry;
|
||||
}
|
||||
|
||||
struct cache_extent *first_cache_extent(struct cache_tree *tree)
|
||||
{
|
||||
struct rb_node *node = rb_first(&tree->root);
|
||||
|
||||
if (!node)
|
||||
return NULL;
|
||||
return rb_entry(node, struct cache_extent, rb_node);
|
||||
}
|
||||
|
||||
struct cache_extent *last_cache_extent(struct cache_tree *tree)
|
||||
{
|
||||
struct rb_node *node = rb_last(&tree->root);
|
||||
|
||||
if (!node)
|
||||
return NULL;
|
||||
return rb_entry(node, struct cache_extent, rb_node);
|
||||
}
|
||||
|
||||
struct cache_extent *prev_cache_extent(struct cache_extent *pe)
|
||||
{
|
||||
struct rb_node *node = rb_prev(&pe->rb_node);
|
||||
|
||||
if (!node)
|
||||
return NULL;
|
||||
return rb_entry(node, struct cache_extent, rb_node);
|
||||
}
|
||||
|
||||
struct cache_extent *next_cache_extent(struct cache_extent *pe)
|
||||
{
|
||||
struct rb_node *node = rb_next(&pe->rb_node);
|
||||
|
||||
if (!node)
|
||||
return NULL;
|
||||
return rb_entry(node, struct cache_extent, rb_node);
|
||||
}
|
||||
|
||||
void remove_cache_extent(struct cache_tree *tree, struct cache_extent *pe)
|
||||
{
|
||||
rb_erase(&pe->rb_node, &tree->root);
|
||||
}
|
||||
|
||||
void cache_tree_free_extents(struct cache_tree *tree,
|
||||
free_cache_extent free_func)
|
||||
{
|
||||
struct cache_extent *ce;
|
||||
|
||||
while ((ce = first_cache_extent(tree))) {
|
||||
remove_cache_extent(tree, ce);
|
||||
free_func(ce);
|
||||
}
|
||||
}
|
||||
|
||||
static void free_extent_cache(struct cache_extent *pe)
|
||||
{
|
||||
free(pe);
|
||||
}
|
||||
|
||||
void free_extent_cache_tree(struct cache_tree *tree)
|
||||
{
|
||||
cache_tree_free_extents(tree, free_extent_cache);
|
||||
}
|
||||
|
||||
int add_merge_cache_extent(struct cache_tree *tree, u64 start, u64 size)
|
||||
{
|
||||
struct cache_extent *cache;
|
||||
struct cache_extent *next = NULL;
|
||||
struct cache_extent *prev = NULL;
|
||||
int next_merged = 0;
|
||||
int prev_merged = 0;
|
||||
int ret = 0;
|
||||
|
||||
if (cache_tree_empty(tree))
|
||||
goto insert;
|
||||
|
||||
cache = search_cache_extent(tree, start);
|
||||
if (!cache) {
|
||||
/*
|
||||
* Either the tree is completely empty, or the no range after
|
||||
* start.
|
||||
* Either way, the last cache_extent should be prev.
|
||||
*/
|
||||
prev = last_cache_extent(tree);
|
||||
} else if (start <= cache->start) {
|
||||
next = cache;
|
||||
prev = prev_cache_extent(cache);
|
||||
} else {
|
||||
prev = cache;
|
||||
next = next_cache_extent(cache);
|
||||
}
|
||||
|
||||
/*
|
||||
* Ensure the range to be inserted won't cover with existings
|
||||
* Or we will need extra loop to do merge
|
||||
*/
|
||||
BUG_ON(next && start + size > next->start);
|
||||
BUG_ON(prev && prev->start + prev->size > start);
|
||||
|
||||
if (next && start + size == next->start) {
|
||||
next_merged = 1;
|
||||
next->size = next->start + next->size - start;
|
||||
next->start = start;
|
||||
}
|
||||
if (prev && prev->start + prev->size == start) {
|
||||
prev_merged = 1;
|
||||
if (next_merged) {
|
||||
next->size = next->start + next->size - prev->start;
|
||||
next->start = prev->start;
|
||||
remove_cache_extent(tree, prev);
|
||||
free(prev);
|
||||
} else {
|
||||
prev->size = start + size - prev->start;
|
||||
}
|
||||
}
|
||||
insert:
|
||||
if (!prev_merged && !next_merged)
|
||||
ret = add_cache_extent(tree, start, size);
|
||||
return ret;
|
||||
}
|
||||
104
fs/btrfs/extent-cache.h
Normal file
104
fs/btrfs/extent-cache.h
Normal file
@ -0,0 +1,104 @@
|
||||
// SPDX-License-Identifier: GPL-2.0+
|
||||
|
||||
/*
|
||||
* Crossported from the same named file of btrfs-progs.
|
||||
*
|
||||
* Minor modification to include headers.
|
||||
*/
|
||||
#ifndef __BTRFS_EXTENT_CACHE_H__
|
||||
#define __BTRFS_EXTENT_CACHE_H__
|
||||
|
||||
#include <linux/rbtree.h>
|
||||
#include <linux/types.h>
|
||||
|
||||
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 *last_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);
|
||||
|
||||
/*
|
||||
* Find a cache_extent which covers start.
|
||||
*
|
||||
* If not found, return next cache_extent if possible.
|
||||
*/
|
||||
struct cache_extent *search_cache_extent(struct cache_tree *tree, u64 start);
|
||||
|
||||
/*
|
||||
* Find a cache_extent which restrictly covers start.
|
||||
*
|
||||
* If not found, return NULL.
|
||||
*/
|
||||
struct cache_extent *lookup_cache_extent(struct cache_tree *tree,
|
||||
u64 start, u64 size);
|
||||
|
||||
/*
|
||||
* Add an non-overlap extent into cache tree
|
||||
*
|
||||
* If [start, start+size) overlap with existing one, it will return -EEXIST.
|
||||
*/
|
||||
int add_cache_extent(struct cache_tree *tree, u64 start, u64 size);
|
||||
|
||||
/*
|
||||
* Same with add_cache_extent, but with cache_extent strcut.
|
||||
*/
|
||||
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);
|
||||
|
||||
/*
|
||||
* Search a cache_extent with same objectid, and covers start.
|
||||
*
|
||||
* If not found, return next if possible.
|
||||
*/
|
||||
struct cache_extent *search_cache_extent2(struct cache_tree *tree,
|
||||
u64 objectid, u64 start);
|
||||
/*
|
||||
* Search a cache_extent with same objectid, and covers the range
|
||||
* [start, start + size)
|
||||
*
|
||||
* If not found, return next cache_extent if possible.
|
||||
*/
|
||||
struct cache_extent *lookup_cache_extent2(struct cache_tree *tree,
|
||||
u64 objectid, u64 start, u64 size);
|
||||
int insert_cache_extent2(struct cache_tree *tree, struct cache_extent *pe);
|
||||
|
||||
/*
|
||||
* Insert a cache_extent range [start, start + size).
|
||||
*
|
||||
* This function may merge with existing cache_extent.
|
||||
* NOTE: caller must ensure the inserted range won't cover with any existing
|
||||
* range.
|
||||
*/
|
||||
int add_merge_cache_extent(struct cache_tree *tree, u64 start, u64 size);
|
||||
|
||||
#endif
|
||||
Loading…
Reference in New Issue
Block a user