@@ -168,4 +168,102 @@ btrfs_backref_iter_release(struct btrfs_backref_iter *iter)
memset(&iter->cur_key, 0, sizeof(iter->cur_key));
}
+/*
+ * Backref cache related structures.
+ *
+ * The whole objective of backref_cache is to build a bi-directional map
+ * of tree blocks (represented by backref_node) and all their parents.
+ */
+
+/*
+ * present a tree block in the backref cache
+ */
+struct backref_node {
+ struct rb_node rb_node;
+ u64 bytenr;
+
+ u64 new_bytenr;
+ /* objectid of tree block owner, can be not uptodate */
+ u64 owner;
+ /* link to pending, changed or detached list */
+ struct list_head list;
+
+ /* List of upper level edges, which links this node to its parent(s) */
+ struct list_head upper;
+ /* List of lower level edges, which links this node to its child(ren) */
+ struct list_head lower;
+
+ /* NULL if this node is not tree root */
+ struct btrfs_root *root;
+ /* extent buffer got by COW the block */
+ struct extent_buffer *eb;
+ /* level of tree block */
+ unsigned int level:8;
+ /* is the block in non-reference counted tree */
+ unsigned int cowonly:1;
+ /* 1 if no child node in the cache */
+ unsigned int lowest:1;
+ /* is the extent buffer locked */
+ unsigned int locked:1;
+ /* has the block been processed */
+ unsigned int processed:1;
+ /* have backrefs of this block been checked */
+ unsigned int checked:1;
+ /*
+ * 1 if corresponding block has been cowed but some upper
+ * level block pointers may not point to the new location
+ */
+ unsigned int pending:1;
+ /*
+ * 1 if the backref node isn't connected to any other
+ * backref node.
+ */
+ unsigned int detached:1;
+};
+
+#define LOWER 0
+#define UPPER 1
+
+/*
+ * present an edge connecting upper and lower backref nodes.
+ */
+struct backref_edge {
+ /*
+ * list[LOWER] is linked to backref_node::upper of lower level node,
+ * and list[UPPER] is linked to backref_node::lower of upper level node.
+ *
+ * Also, build_backref_tree() uses list[UPPER] for pending edges, before
+ * linking list[UPPER] to its upper level nodes.
+ */
+ struct list_head list[2];
+
+ /* Two related nodes */
+ struct backref_node *node[2];
+};
+
+
+struct backref_cache {
+ /* red black tree of all backref nodes in the cache */
+ struct rb_root rb_root;
+ /* for passing backref nodes to btrfs_reloc_cow_block */
+ struct backref_node *path[BTRFS_MAX_LEVEL];
+ /*
+ * list of blocks that have been cowed but some block
+ * pointers in upper level blocks may not reflect the
+ * new location
+ */
+ struct list_head pending[BTRFS_MAX_LEVEL];
+ /* list of backref nodes with no child node */
+ struct list_head leaves;
+ /* list of blocks that have been cowed in current transaction */
+ struct list_head changed;
+ /* list of detached backref node. */
+ struct list_head detached;
+
+ u64 last_trans;
+
+ int nr_nodes;
+ int nr_edges;
+};
+
#endif
@@ -24,6 +24,8 @@
#include "block-group.h"
#include "backref.h"
+#define RELOCATION_RESERVED_NODES 256
+
/*
* Relocation overview
*
@@ -79,97 +81,6 @@ struct tree_entry {
u64 bytenr;
};
-/*
- * present a tree block in the backref cache
- */
-struct backref_node {
- struct rb_node rb_node;
- u64 bytenr;
-
- u64 new_bytenr;
- /* objectid of tree block owner, can be not uptodate */
- u64 owner;
- /* link to pending, changed or detached list */
- struct list_head list;
-
- /* List of upper level edges, which links this node to its parent(s) */
- struct list_head upper;
- /* List of lower level edges, which links this node to its child(ren) */
- struct list_head lower;
-
- /* NULL if this node is not tree root */
- struct btrfs_root *root;
- /* extent buffer got by COW the block */
- struct extent_buffer *eb;
- /* level of tree block */
- unsigned int level:8;
- /* is the block in non-reference counted tree */
- unsigned int cowonly:1;
- /* 1 if no child node in the cache */
- unsigned int lowest:1;
- /* is the extent buffer locked */
- unsigned int locked:1;
- /* has the block been processed */
- unsigned int processed:1;
- /* have backrefs of this block been checked */
- unsigned int checked:1;
- /*
- * 1 if corresponding block has been cowed but some upper
- * level block pointers may not point to the new location
- */
- unsigned int pending:1;
- /*
- * 1 if the backref node isn't connected to any other
- * backref node.
- */
- unsigned int detached:1;
-};
-
-#define LOWER 0
-#define UPPER 1
-#define RELOCATION_RESERVED_NODES 256
-/*
- * present an edge connecting upper and lower backref nodes.
- */
-struct backref_edge {
- /*
- * list[LOWER] is linked to backref_node::upper of lower level node,
- * and list[UPPER] is linked to backref_node::lower of upper level node.
- *
- * Also, build_backref_tree() uses list[UPPER] for pending edges, before
- * linking list[UPPER] to its upper level nodes.
- */
- struct list_head list[2];
-
- /* Two related nodes */
- struct backref_node *node[2];
-};
-
-
-struct backref_cache {
- /* red black tree of all backref nodes in the cache */
- struct rb_root rb_root;
- /* for passing backref nodes to btrfs_reloc_cow_block */
- struct backref_node *path[BTRFS_MAX_LEVEL];
- /*
- * list of blocks that have been cowed but some block
- * pointers in upper level blocks may not reflect the
- * new location
- */
- struct list_head pending[BTRFS_MAX_LEVEL];
- /* list of backref nodes with no child node */
- struct list_head leaves;
- /* list of blocks that have been cowed in current transaction */
- struct list_head changed;
- /* list of detached backref node. */
- struct list_head detached;
-
- u64 last_trans;
-
- int nr_nodes;
- int nr_edges;
-};
-
/*
* map address of tree root to tree
*/
These 3 structures are the main part of backref cache, move them to backref.h to build the basis for later reuse. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/backref.h | 98 +++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/relocation.c | 93 +--------------------------------------- 2 files changed, 100 insertions(+), 91 deletions(-)