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>
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 85ae2b6..fff2c28 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -49,7 +49,7 @@
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 @@
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 @@
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);
}