Btrfs: log changed inodes based on the extent map tree

We don't really need to copy extents from the source tree since we have all
of the information already available to us in the extent_map tree.  So
instead just write the extents straight to the log tree and don't bother to
copy the extent items from the source tree.

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This commit is contained in:
Josef Bacik
2012-10-11 16:54:30 -04:00
committed by Chris Mason
parent d6393786cd
commit 70c8a91ce2
7 changed files with 376 additions and 214 deletions

View File

@@ -49,7 +49,7 @@ void extent_map_tree_init(struct extent_map_tree *tree)
struct extent_map *alloc_extent_map(void)
{
struct extent_map *em;
em = kmem_cache_alloc(extent_map_cache, GFP_NOFS);
em = kmem_cache_zalloc(extent_map_cache, GFP_NOFS);
if (!em)
return NULL;
em->in_tree = 0;
@@ -198,16 +198,15 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
merge = rb_entry(rb, struct extent_map, rb_node);
if (rb && mergable_maps(merge, em)) {
em->start = merge->start;
em->orig_start = merge->orig_start;
em->len += merge->len;
em->block_len += merge->block_len;
em->block_start = merge->block_start;
merge->in_tree = 0;
if (merge->generation > em->generation) {
em->mod_start = em->start;
em->mod_len = em->len;
em->generation = merge->generation;
list_move(&em->list, &tree->modified_extents);
}
em->mod_len = (em->mod_len + em->mod_start) - merge->mod_start;
em->mod_start = merge->mod_start;
em->generation = max(em->generation, merge->generation);
list_move(&em->list, &tree->modified_extents);
list_del_init(&merge->list);
rb_erase(&merge->rb_node, &tree->map);
@@ -223,11 +222,8 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
em->block_len += merge->len;
rb_erase(&merge->rb_node, &tree->map);
merge->in_tree = 0;
if (merge->generation > em->generation) {
em->mod_len = em->len;
em->generation = merge->generation;
list_move(&em->list, &tree->modified_extents);
}
em->mod_len = (merge->mod_start + merge->mod_len) - em->mod_start;
em->generation = max(em->generation, merge->generation);
list_del_init(&merge->list);
free_extent_map(merge);
}