Add generation numbers to block pointers

ctree.c

@@ -23,6 +23,7 @@
 #include "disk-io.h"
 #include "transaction.h"
 #include "print-tree.h"
+
 static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
 		      *root, struct btrfs_path *path, int level);
 static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
@@ -80,6 +81,8 @@ int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root
 	} else {
 		btrfs_set_node_blockptr(&parent->node, parent_slot,
 					cow->bytenr);
+		btrfs_set_node_ptr_generation(&parent->node, parent_slot,
+					      trans->transid);
 		BUG_ON(list_empty(&parent->dirty));
 		btrfs_free_extent(trans, root, buf->bytenr, buf->size, 1);
 	}
@@ -849,6 +852,8 @@ static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root
 	memcpy(&c->ptrs[0].key, lower_key, sizeof(struct btrfs_disk_key));
 	btrfs_set_node_blockptr(c, 0, path->nodes[level - 1]->bytenr);
 	BUG_ON(list_empty(&t->dirty));
+	btrfs_set_node_ptr_generation(c, 0,
+	         btrfs_header_generation(&path->nodes[level - 1]->node.header));
 	/* the super has an extra ref to root->node */
 	btrfs_block_release(root, root->node);
 	root->node = t;
@@ -887,6 +892,7 @@ static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root
 	}
 	memcpy(&lower->ptrs[slot].key, key, sizeof(struct btrfs_disk_key));
 	btrfs_set_node_blockptr(lower, slot, bytenr);
+	btrfs_set_node_ptr_generation(lower, slot, trans->transid);
 	btrfs_set_header_nritems(&lower->header, nritems + 1);
 	BUG_ON(list_empty(&path->nodes[level]->dirty));
 	return 0;
@@ -1287,9 +1293,9 @@ again:
 	right = &right_buffer->leaf;
 	memset(&right->header, 0, sizeof(right->header));
 	btrfs_set_header_bytenr(&right->header, right_buffer->bytenr);
-	btrfs_set_header_generation(&right->header, trans->transid);
 	btrfs_set_header_level(&right->header, 0);
 	btrfs_set_header_owner(&right->header, root->root_key.objectid);
+	btrfs_set_header_generation(&right->header, trans->transid);
 	memcpy(right->header.fsid, root->fs_info->disk_super->fsid,
 	       sizeof(right->header.fsid));
 	if (mid <= slot) {

ctree.h

@@ -98,7 +98,7 @@ struct btrfs_header {
 #define BTRFS_MAX_LEVEL 8
 #define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \
 			        sizeof(struct btrfs_header)) / \
-			       (sizeof(struct btrfs_disk_key) + sizeof(u64)))
+			       sizeof(struct btrfs_key_ptr))
 #define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
 #define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->leafsize))
 #define BTRFS_MAX_INLINE_DATA_SIZE(r) (BTRFS_LEAF_DATA_SIZE(r) - \
@@ -156,6 +156,7 @@ struct btrfs_leaf {
 struct btrfs_key_ptr {
 	struct btrfs_disk_key key;
 	__le64 blockptr;
+	__le64 generation;
 } __attribute__ ((__packed__));
 
 struct btrfs_node {
@@ -562,13 +563,23 @@ static inline u64 btrfs_node_blockptr(struct btrfs_node *n, int nr)
 	return le64_to_cpu(n->ptrs[nr].blockptr);
 }
 
-
 static inline void btrfs_set_node_blockptr(struct btrfs_node *n, int nr,
 					   u64 val)
 {
 	n->ptrs[nr].blockptr = cpu_to_le64(val);
 }
 
+static inline u64 btrfs_node_ptr_generation(struct btrfs_node *n, int nr)
+{
+	return le64_to_cpu(n->ptrs[nr].generation);
+}
+
+static inline void btrfs_set_node_ptr_generation(struct btrfs_node *n, int nr,
+						 u64 val)
+{
+	n->ptrs[nr].generation = cpu_to_le64(val);
+}
+
 static inline u32 btrfs_item_offset(struct btrfs_item *item)
 {
 	return le32_to_cpu(item->offset);

extent-tree.c

@@ -572,8 +572,7 @@ struct btrfs_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
 		return NULL;
 	}
 	buf = find_tree_block(root, ins.objectid, blocksize);
-	btrfs_set_header_generation(&buf->node.header,
-				    root->root_key.offset + 1);
+	btrfs_set_header_generation(&buf->node.header, trans->transid);
 	btrfs_set_header_bytenr(&buf->node.header, buf->bytenr);
 	memcpy(buf->node.header.fsid, root->fs_info->disk_super->fsid,
 	       sizeof(buf->node.header.fsid));

mkfs.c

@@ -224,7 +224,7 @@ printf("blocksize is %d\n", leafsize);
 	memset(empty_leaf, 0, leafsize);
 	btrfs_set_header_bytenr(&empty_leaf->header, first_free);
 	btrfs_set_header_nritems(&empty_leaf->header, 2);
-	btrfs_set_header_generation(&empty_leaf->header, 0);
+	btrfs_set_header_generation(&empty_leaf->header, 1);
 	btrfs_set_header_owner(&empty_leaf->header, BTRFS_ROOT_TREE_OBJECTID);
 	memcpy(empty_leaf->header.fsid, super.fsid,
 	       sizeof(empty_leaf->header.fsid));

print-tree.c

@@ -179,13 +179,14 @@ void btrfs_print_tree(struct btrfs_root *root, struct btrfs_buffer *t)
 	size = btrfs_level_size(root, btrfs_header_level(&c->header) - 1);
 	for (i = 0; i < nr; i++) {
 		u64 blocknr = btrfs_node_blockptr(c, i);
-		printf("\tkey %d (%llu %x %llu) block %llu (%llu)\n",
+		printf("\tkey %d (%llu %x %llu) block %llu (%llu) gen %llu\n",
 		       i,
 		       (unsigned long long)c->ptrs[i].key.objectid,
 		       c->ptrs[i].key.type,
 		       (unsigned long long)c->ptrs[i].key.offset,
 		       (unsigned long long)blocknr,
-		       (unsigned long long)blocknr / size);
+		       (unsigned long long)blocknr / size,
+		       (unsigned long long)btrfs_node_ptr_generation(c, i));
 		fflush(stdout);
 	}
 	for (i = 0; i < nr; i++) {