Btrfs: Index extent buffers in an rbtree
Before, extent buffers were a temporary object, meant to map a number of pages
at once and collect operations on them.
But, a few extra fields have crept in, and they are also the best place to
store a per-tree block lock field as well. This commit puts the extent
buffers into an rbtree, and ensures a single extent buffer for each
tree block.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 23affd2..dd36761 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -54,13 +54,12 @@
struct extent_io_tree {
struct rb_root state;
+ struct rb_root buffer;
struct address_space *mapping;
u64 dirty_bytes;
spinlock_t lock;
+ spinlock_t buffer_lock;
struct extent_io_ops *ops;
- spinlock_t lru_lock;
- struct list_head buffer_lru;
- int lru_size;
struct extent_state *last;
};
@@ -87,10 +86,10 @@
unsigned long map_start;
unsigned long map_len;
struct page *first_page;
- struct list_head lru;
atomic_t refs;
int flags;
struct list_head leak_list;
+ struct rb_node rb_node;
};
struct extent_map_tree;
@@ -112,10 +111,10 @@
void extent_io_tree_init(struct extent_io_tree *tree,
struct address_space *mapping, gfp_t mask);
-void extent_io_tree_empty_lru(struct extent_io_tree *tree);
int try_release_extent_mapping(struct extent_map_tree *map,
struct extent_io_tree *tree, struct page *page,
gfp_t mask);
+int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page);
int try_release_extent_state(struct extent_map_tree *map,
struct extent_io_tree *tree, struct page *page,
gfp_t mask);
@@ -241,8 +240,6 @@
unsigned long *map_start,
unsigned long *map_len, int km);
void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
-int invalidate_extent_lru(struct extent_io_tree *tree, u64 start,
- unsigned long len);
int release_extent_buffer_tail_pages(struct extent_buffer *eb);
int extent_range_uptodate(struct extent_io_tree *tree,
u64 start, u64 end);
