Pass down the expected generation number when reading tree blocks

7 files changed, 52 insertions, 50 deletions

diff --git a/btrfsck.c b/btrfsck.c
index b4472251..e367840b 100644
--- a/btrfsck.c
+++ b/btrfsck.c
@@ -511,7 +511,10 @@ static int run_next_block(struct btrfs_root *root,
 		for(i = 0; i < ret; i++) {
 			insert_cache_extent(reada, bits[i].start,
 					    bits[i].size);
-			readahead_tree_block(root, bits[i].start, bits[i].size);
+
+			/* fixme, get the parent transid */
+			readahead_tree_block(root, bits[i].start,
+					     bits[i].size, 0);
 		}
 	}
 	*last = bits[0].start;
@@ -534,7 +537,8 @@ static int run_next_block(struct btrfs_root *root,
 		free(cache);
 	}
 
-	buf = read_tree_block(root, bytenr, size);
+	/* fixme, get the real parent transid */
+	buf = read_tree_block(root, bytenr, size, 0);
 	nritems = btrfs_header_nritems(buf);
 	ret = check_block(root, extent_cache, buf);
 	if (ret) {
@@ -790,7 +794,7 @@ int main(int ac, char **av) {
 			buf = read_tree_block(root->fs_info->tree_root,
 					      btrfs_root_bytenr(&ri),
 					      btrfs_level_size(root,
-						       btrfs_root_level(&ri)));
+					       btrfs_root_level(&ri)), 0);
 			add_root_to_pending(buf, bits, bits_nr, &extent_cache,
 					    &pending, &seen, &reada, &nodes,
 					    found_key.objectid);
diff --git a/ctree.c b/ctree.c
index 5608bb47..87574d9e 100644
--- a/ctree.c
+++ b/ctree.c
@@ -301,6 +301,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 	struct extent_buffer *cur;
 	struct extent_buffer *tmp;
 	u64 blocknr;
+	u64 gen;
 	u64 search_start = *last_ret;
 	u64 last_block = 0;
 	u64 other;
@@ -353,6 +354,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 
 		progress_passed = 1;
 		blocknr = btrfs_node_blockptr(parent, i);
+		gen = btrfs_node_ptr_generation(parent, i);
 		if (last_block == 0)
 			last_block = blocknr;
 
@@ -386,9 +388,9 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 			}
 			if (!cur) {
 				cur = read_tree_block(root, blocknr,
-							 blocksize);
+							 blocksize, gen);
 			} else if (!uptodate) {
-				btrfs_read_buffer(cur);
+				btrfs_read_buffer(cur, gen);
 			}
 		}
 		if (search_start == 0)
@@ -651,12 +653,17 @@ static int bin_search(struct extent_buffer *eb, struct btrfs_key *key,
 static struct extent_buffer *read_node_slot(struct btrfs_root *root,
 				   struct extent_buffer *parent, int slot)
 {
+	int level = btrfs_header_level(parent);
 	if (slot < 0)
 		return NULL;
 	if (slot >= btrfs_header_nritems(parent))
 		return NULL;
+
+	BUG_ON(level == 0);
+
 	return read_tree_block(root, btrfs_node_blockptr(parent, slot),
-		       btrfs_level_size(root, btrfs_header_level(parent) - 1));
+		       btrfs_level_size(root, level - 1),
+		       btrfs_node_ptr_generation(parent, slot));
 }
 
 static int balance_level(struct btrfs_trans_handle *trans,
@@ -1034,7 +1041,8 @@ static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
 		if ((search >= lowest_read && search <= highest_read) ||
 		    (search < lowest_read && lowest_read - search <= 32768) ||
 		    (search > highest_read && search - highest_read <= 32768)) {
-			readahead_tree_block(root, search, blocksize);
+			readahead_tree_block(root, search, blocksize,
+				     btrfs_node_ptr_generation(node, nr));
 			nread += blocksize;
 		}
 		nscan++;
@@ -1068,8 +1076,6 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
 		      ins_len, int cow)
 {
 	struct extent_buffer *b;
-	u64 bytenr;
-	u64 ptr_gen;
 	int slot;
 	int ret;
 	int level;
@@ -1135,20 +1141,12 @@ again:
 			/* this is only true while dropping a snapshot */
 			if (level == lowest_level)
 				break;
-			bytenr = btrfs_node_blockptr(b, slot);
-			ptr_gen = btrfs_node_ptr_generation(b, slot);
+
 			if (should_reada)
 				reada_for_search(root, p, level, slot,
 						 key->objectid);
-			b = read_tree_block(root, bytenr,
-					    btrfs_level_size(root, level - 1));
-			if (ptr_gen != btrfs_header_generation(b)) {
-				printk("block %llu bad gen wanted %llu "
-				       "found %llu\n",
-			        (unsigned long long)b->start,
-				(unsigned long long)ptr_gen,
-			        (unsigned long long)btrfs_header_generation(b));
-			}
+
+			b = read_node_slot(root, b, slot);
 		} else {
 			p->slots[level] = slot;
 			if (ins_len > 0 && btrfs_leaf_free_space(root, b) <
@@ -1611,8 +1609,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
 	if (slot >= btrfs_header_nritems(upper) - 1)
 		return 1;
 
-	right = read_tree_block(root, btrfs_node_blockptr(upper, slot + 1),
-				root->leafsize);
+	right = read_node_slot(root, upper, slot + 1);
 	free_space = btrfs_leaf_free_space(root, right);
 	if (free_space < data_size + sizeof(struct btrfs_item)) {
 		free_extent_buffer(right);
@@ -1764,8 +1761,7 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
 		return 1;
 	}
 
-	left = read_tree_block(root, btrfs_node_blockptr(path->nodes[1],
-			       slot - 1), root->leafsize);
+	left = read_node_slot(root, path->nodes[1], slot - 1);
 	free_space = btrfs_leaf_free_space(root, left);
 	if (free_space < data_size + sizeof(struct btrfs_item)) {
 		free_extent_buffer(left);
@@ -2576,7 +2572,6 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
  */
 int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
-	u64 bytenr;
 	int slot;
 	int level = 1;
 	struct extent_buffer *c;
@@ -2596,12 +2591,10 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
 		}
 		slot--;
 
-		bytenr = btrfs_node_blockptr(c, slot);
 		if (next)
 			free_extent_buffer(next);
 
-		next = read_tree_block(root, bytenr,
-				       btrfs_level_size(root, level - 1));
+		next = read_node_slot(root, c, slot);
 		break;
 	}
 	path->slots[level] = slot;
@@ -2616,8 +2609,7 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
 		path->slots[level] = slot;
 		if (!level)
 			break;
-		next = read_tree_block(root, btrfs_node_blockptr(next, slot),
-				       btrfs_level_size(root, level - 1));
+		next = read_node_slot(root, next, slot);
 	}
 	return 0;
 }
@@ -2631,7 +2623,6 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
 	int slot;
 	int level = 1;
-	u64 bytenr;
 	struct extent_buffer *c;
 	struct extent_buffer *next = NULL;
 
@@ -2648,15 +2639,13 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 			continue;
 		}
 
-		bytenr = btrfs_node_blockptr(c, slot);
 		if (next)
 			free_extent_buffer(next);
 
 		if (path->reada)
 			reada_for_search(root, path, level, slot, 0);
 
-		next = read_tree_block(root, bytenr,
-				       btrfs_level_size(root, level -1));
+		next = read_node_slot(root, c, slot);
 		break;
 	}
 	path->slots[level] = slot;
@@ -2670,8 +2659,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 			break;
 		if (path->reada)
 			reada_for_search(root, path, level, 0, 0);
-		next = read_tree_block(root, btrfs_node_blockptr(next, 0),
-				       btrfs_level_size(root, level - 1));
+		next = read_node_slot(root, next, 0);
 	}
 	return 0;
 }
diff --git a/debug-tree.c b/debug-tree.c
index 21162ecf..fa5c90c3 100644
--- a/debug-tree.c
+++ b/debug-tree.c
@@ -86,7 +86,8 @@ static void print_extents(struct btrfs_root *root, struct extent_buffer *eb)
 	for (i = 0; i < nr; i++) {
 		struct extent_buffer *next = read_tree_block(root,
 					     btrfs_node_blockptr(eb, i),
-					     size);
+					     size,
+					     btrfs_node_ptr_generation(eb, i));
 		if (btrfs_is_leaf(next) &&
 		    btrfs_header_level(eb) != 1)
 			BUG();
@@ -171,7 +172,7 @@ int main(int ac, char **av)
 			read_extent_buffer(leaf, &ri, offset, sizeof(ri));
 			buf = read_tree_block(root->fs_info->tree_root,
 					      btrfs_root_bytenr(&ri),
-					      root->leafsize);
+					      root->leafsize, 0);
 			switch(found_key.objectid) {
 			case BTRFS_ROOT_TREE_OBJECTID:
 				if (!skip)
diff --git a/disk-io.c b/disk-io.c
index 939f7727..687cc61e 100644
--- a/disk-io.c
+++ b/disk-io.c
@@ -95,7 +95,8 @@ struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
 				   blocksize);
 }
 
-int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize)
+int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
+			 u64 parent_transid)
 {
 	int ret;
 	int dev_nr;
@@ -124,7 +125,7 @@ int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize)
 }
 
 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
-				     u32 blocksize)
+				     u32 blocksize, u64 parent_transid)
 {
 	int ret;
 	int dev_nr;
@@ -380,7 +381,7 @@ static int find_and_setup_root(struct btrfs_root *tree_root,
 
 	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-				     blocksize);
+				     blocksize, 0);
 	BUG_ON(!root->node);
 	return 0;
 }
@@ -447,7 +448,7 @@ out:
 	}
 	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
-				     blocksize);
+				     blocksize, 0);
 	BUG_ON(!root->node);
 insert:
 	root->ref_cows = 1;
@@ -585,7 +586,7 @@ struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
 
 	chunk_root->node = read_tree_block(chunk_root,
 					   btrfs_super_chunk_root(disk_super),
-					   blocksize);
+					   blocksize, 0);
 
 	BUG_ON(!chunk_root->node);
 
@@ -601,7 +602,7 @@ struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
 
 	tree_root->node = read_tree_block(tree_root,
 					  btrfs_super_root(disk_super),
-					  blocksize);
+					  blocksize, 0);
 	BUG_ON(!tree_root->node);
 	ret = find_and_setup_root(tree_root, fs_info,
 				  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
diff --git a/disk-io.h b/disk-io.h
index b0328445..ffb4114b 100644
--- a/disk-io.h
+++ b/disk-io.h
@@ -25,8 +25,9 @@
 struct btrfs_device;
 
 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
-				      u32 blocksize);
-int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize);
+				      u32 blocksize, u64 parent_transid);
+int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
+			 u64 parent_transid);
 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
 						   u64 bytenr, u32 blocksize);
 int clean_tree_block(struct btrfs_trans_handle *trans,
@@ -57,4 +58,5 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 int btrfs_open_device(struct btrfs_device *dev);
 int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 		    int verify);
+int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
 #endif
diff --git a/extent-tree.c b/extent-tree.c
index 1d1dbc8b..545884a9 100644
--- a/extent-tree.c
+++ b/extent-tree.c
@@ -1225,7 +1225,8 @@ static int finish_current_insert(struct btrfs_trans_handle *trans,
 					&extent_item, sizeof(extent_item));
 		clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
 				  GFP_NOFS);
-		eb = read_tree_block(extent_root, ins.objectid, ins.offset);
+		eb = read_tree_block(extent_root, ins.objectid, ins.offset,
+				     trans->transid);
 		level = btrfs_header_level(eb);
 		if (level == 0) {
 			btrfs_item_key(eb, &first, 0);
@@ -1892,7 +1893,8 @@ static void noinline reada_walk_down(struct btrfs_root *root,
 			}
 		}
 		mutex_unlock(&root->fs_info->fs_mutex);
-		ret = readahead_tree_block(root, bytenr, blocksize);
+		ret = readahead_tree_block(root, bytenr, blocksize,
+					   btrfs_node_ptr_generation(node, i));
 		last = bytenr + blocksize;
 		cond_resched();
 		mutex_lock(&root->fs_info->fs_mutex);
@@ -1912,6 +1914,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
 	u64 root_owner;
 	u64 root_gen;
 	u64 bytenr;
+	u64 ptr_gen;
 	struct extent_buffer *next;
 	struct extent_buffer *cur;
 	struct extent_buffer *parent;
@@ -1948,6 +1951,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
 			break;
 		}
 		bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
+		ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
 		blocksize = btrfs_level_size(root, *level - 1);
 		ret = lookup_extent_ref(trans, root, bytenr, blocksize, &refs);
 		BUG_ON(ret);
@@ -1967,7 +1971,8 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
 			free_extent_buffer(next);
 			reada_walk_down(root, cur, path->slots[*level]);
 			mutex_unlock(&root->fs_info->fs_mutex);
-			next = read_tree_block(root, bytenr, blocksize);
+			next = read_tree_block(root, bytenr, blocksize,
+					       ptr_gen);
 			mutex_lock(&root->fs_info->fs_mutex);
 
 			/* we dropped the lock, check one more time */
diff --git a/print-tree.c b/print-tree.c
index f0757764..dd4fcf16 100644
--- a/print-tree.c
+++ b/print-tree.c
@@ -314,7 +314,8 @@ void btrfs_print_tree(struct btrfs_root *root, struct extent_buffer *eb)
 	for (i = 0; i < nr; i++) {
 		struct extent_buffer *next = read_tree_block(root,
 					     btrfs_node_blockptr(eb, i),
-					     size);
+					     size,
+					     btrfs_node_ptr_generation(eb, i));
 		if (btrfs_is_leaf(next) &&
 		    btrfs_header_level(eb) != 1)
 			BUG();