Btrfs: early extent mapping support

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 31 insertions, 3 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 586bf1866042..b737925be314 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1,7 +1,7 @@
 #ifndef __CTREE__
 #define __CTREE__
 
-#define CTREE_BLOCKSIZE 4096
+#define CTREE_BLOCKSIZE 256
 
 struct key {
         u64 objectid;
@@ -22,18 +22,41 @@ struct header {
 #define NODEPTRS_PER_BLOCK ((CTREE_BLOCKSIZE - sizeof(struct header)) / \
                             (sizeof(struct key) + sizeof(u64)))
 
-#define LEVEL_BITS 3
-#define MAX_LEVEL (1 << LEVEL_BITS)
+#define MAX_LEVEL 8
 #define node_level(f) ((f) & (MAX_LEVEL-1))
 #define is_leaf(f) (node_level(f) == 0)
 
 struct tree_buffer;
+
+struct alloc_extent {
+        u64 blocknr;
+        u64 num_blocks;
+        u64 num_used;
+} __attribute__ ((__packed__));
+
 struct ctree_root {
         struct tree_buffer *node;
+        struct ctree_root *extent_root;
+        struct alloc_extent *alloc_extent;
+        struct alloc_extent *reserve_extent;
         int fp;
         struct radix_tree_root cache_radix;
+        struct alloc_extent ai1;
+        struct alloc_extent ai2;
 };
 
+struct ctree_root_info {
+        u64 fsid[2]; /* FS specific uuid */
+        u64 blocknr; /* blocknr of this block */
+        u64 objectid; /* inode number of this root */
+        u64 tree_root; /* the tree root */
+        u32 csum;
+        u32 ham;
+        struct alloc_extent alloc_extent;
+        struct alloc_extent reserve_extent;
+        u64 snapuuid[2]; /* root specific uuid */
+} __attribute__ ((__packed__));
+
 struct item {
         struct key key;
         u16 offset;
@@ -55,6 +78,11 @@ struct node {
         u64 blockptrs[NODEPTRS_PER_BLOCK];
 } __attribute__ ((__packed__));
 
+struct extent_item {
+        u32 refs;
+        u64 owner;
+} __attribute__ ((__packed__));
+
 struct ctree_path {
         struct tree_buffer *nodes[MAX_LEVEL];
         int slots[MAX_LEVEL];