Btrfs: Add zlib compression support

[linux-2.6-block.git] / fs / btrfs / extent_map.c

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 74b2a29880d36a3db2e40efcf45b8784319998ee..fd3ebfb8c3c5e80bf440c21e6541d976325bcef2 100644 (file)
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -184,6 +184,13 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next)
        if (test_bit(EXTENT_FLAG_PINNED, &prev->flags))
                return 0;
 
+       /*
+        * don't merge compressed extents, we need to know their
+        * actual size
+        */
+       if (test_bit(EXTENT_FLAG_COMPRESSED, &prev->flags))
+               return 0;
+
        if (extent_map_end(prev) == next->start &&
            prev->flags == next->flags &&
            prev->bdev == next->bdev &&
@@ -239,6 +246,7 @@ int add_extent_mapping(struct extent_map_tree *tree,
                if (rb && mergable_maps(merge, em)) {
                        em->start = merge->start;
                        em->len += merge->len;
+                       em->block_len += merge->block_len;
                        em->block_start = merge->block_start;
                        merge->in_tree = 0;
                        rb_erase(&merge->rb_node, &tree->map);
@@ -250,6 +258,7 @@ int add_extent_mapping(struct extent_map_tree *tree,
                merge = rb_entry(rb, struct extent_map, rb_node);
        if (rb && mergable_maps(em, merge)) {
                em->len += merge->len;
+               em->block_len += merge->len;
                rb_erase(&merge->rb_node, &tree->map);
                merge->in_tree = 0;
                free_extent_map(merge);