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btrfs-progs: port block group cache tree insertion and lookup functions 

Simple copy and paste, remove useless lock operantions in progs.  Th new
coming lookup functions are temporarily named with suffix _kernel.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <Damenly_Su@gmx.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Su Yue 2019-12-18 13:18:42 +08:00 committed by David Sterba
parent 2eaf862f46
commit ff49668b71
1 changed files with 86 additions and 0 deletions
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86
extent-tree.c
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@ -164,6 +164,92 @@ err:
return 0;
}
/*
* This adds the block group to the fs_info rb tree for the block group cache
*/
static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
struct btrfs_block_group_cache *block_group)
{
struct rb_node **p;
struct rb_node *parent = NULL;
struct btrfs_block_group_cache *cache;
p = &info->block_group_cache_tree.rb_node;
while (*p) {
parent = *p;
cache = rb_entry(parent, struct btrfs_block_group_cache,
cache_node);
if (block_group->key.objectid < cache->key.objectid)
p = &(*p)->rb_left;
else if (block_group->key.objectid > cache->key.objectid)
p = &(*p)->rb_right;
else
return -EEXIST;
}
rb_link_node(&block_group->cache_node, parent, p);
rb_insert_color(&block_group->cache_node,
&info->block_group_cache_tree);
return 0;
}
/*
* This will return the block group at or after bytenr if contains is 0, else
* it will return the block group that contains the bytenr
*/
static struct btrfs_block_group_cache *block_group_cache_tree_search(
struct btrfs_fs_info *info, u64 bytenr, int contains)
{
struct btrfs_block_group_cache *cache, *ret = NULL;
struct rb_node *n;
u64 end, start;
n = info->block_group_cache_tree.rb_node;
while (n) {
cache = rb_entry(n, struct btrfs_block_group_cache,
cache_node);
end = cache->key.objectid + cache->key.offset - 1;
start = cache->key.objectid;
if (bytenr < start) {
if (!contains && (!ret || start < ret->key.objectid))
ret = cache;
n = n->rb_left;
} else if (bytenr > start) {
if (contains && bytenr <= end) {
ret = cache;
break;
}
n = n->rb_right;
} else {
ret = cache;
break;
}
}
return ret;
}
/*
* Return the block group that starts at or after bytenr
*/
struct btrfs_block_group_cache *btrfs_lookup_first_block_group_kernel(
struct btrfs_fs_info *info, u64 bytenr)
{
return block_group_cache_tree_search(info, bytenr, 0);
}
/*
* Return the block group that contains the given bytenr
*/
struct btrfs_block_group_cache *btrfs_lookup_block_group_kernel(
struct btrfs_fs_info *info, u64 bytenr)
{
return block_group_cache_tree_search(info, bytenr, 1);
}
/*
* Return the block group that contains @bytenr, otherwise return the next one
* that starts after @bytenr