2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public
4 * License v2 as published by the Free Software Foundation.
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
9 * General Public License for more details.
11 * You should have received a copy of the GNU General Public
12 * License along with this program; if not, write to the
13 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
14 * Boston, MA 021110-1307, USA.
17 #include "kerncompat.h"
19 #include "transaction.h"
23 struct btrfs_trans_handle* btrfs_start_transaction(struct btrfs_root *root,
26 struct btrfs_fs_info *fs_info = root->fs_info;
27 struct btrfs_trans_handle *h = kzalloc(sizeof(*h), GFP_NOFS);
30 return ERR_PTR(-ENOMEM);
31 if (root->commit_root) {
32 error("commit_root aleady set when starting transaction");
34 return ERR_PTR(-EINVAL);
36 if (fs_info->running_transaction) {
37 error("attempt to start transaction over already running one");
39 return ERR_PTR(-EINVAL);
41 fs_info->running_transaction = h;
42 fs_info->generation++;
43 h->transid = fs_info->generation;
44 h->blocks_reserved = num_blocks;
45 root->last_trans = h->transid;
46 root->commit_root = root->node;
47 extent_buffer_get(root->node);
52 static int update_cowonly_root(struct btrfs_trans_handle *trans,
53 struct btrfs_root *root)
57 struct btrfs_root *tree_root = root->fs_info->tree_root;
59 btrfs_write_dirty_block_groups(trans, root);
61 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
62 if (old_root_bytenr == root->node->start)
64 btrfs_set_root_bytenr(&root->root_item,
66 btrfs_set_root_generation(&root->root_item,
68 root->root_item.level = btrfs_header_level(root->node);
69 ret = btrfs_update_root(trans, tree_root,
73 btrfs_write_dirty_block_groups(trans, root);
78 int commit_tree_roots(struct btrfs_trans_handle *trans,
79 struct btrfs_fs_info *fs_info)
81 struct btrfs_root *root;
82 struct list_head *next;
83 struct extent_buffer *eb;
86 if (fs_info->readonly)
89 eb = fs_info->tree_root->node;
90 extent_buffer_get(eb);
91 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
92 free_extent_buffer(eb);
96 while(!list_empty(&fs_info->dirty_cowonly_roots)) {
97 next = fs_info->dirty_cowonly_roots.next;
99 root = list_entry(next, struct btrfs_root, dirty_list);
100 update_cowonly_root(trans, root);
101 free_extent_buffer(root->commit_root);
102 root->commit_root = NULL;
108 int __commit_transaction(struct btrfs_trans_handle *trans,
109 struct btrfs_root *root)
113 struct btrfs_fs_info *fs_info = root->fs_info;
114 struct extent_buffer *eb;
115 struct extent_io_tree *tree = &fs_info->extent_cache;
119 ret = find_first_extent_bit(tree, 0, &start, &end,
123 while(start <= end) {
124 eb = find_first_extent_buffer(tree, start);
125 BUG_ON(!eb || eb->start != start);
126 ret = write_tree_block(trans, fs_info, eb);
129 clear_extent_buffer_dirty(eb);
130 free_extent_buffer(eb);
136 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
137 struct btrfs_root *root)
139 u64 transid = trans->transid;
141 struct btrfs_fs_info *fs_info = root->fs_info;
143 if (root->commit_root == root->node)
145 if (root == root->fs_info->tree_root)
147 if (root == root->fs_info->chunk_root)
150 free_extent_buffer(root->commit_root);
151 root->commit_root = NULL;
153 btrfs_set_root_bytenr(&root->root_item, root->node->start);
154 btrfs_set_root_generation(&root->root_item, trans->transid);
155 root->root_item.level = btrfs_header_level(root->node);
156 ret = btrfs_update_root(trans, root->fs_info->tree_root,
157 &root->root_key, &root->root_item);
160 ret = commit_tree_roots(trans, fs_info);
162 ret = __commit_transaction(trans, root);
164 write_ctree_super(trans, fs_info);
165 btrfs_finish_extent_commit(trans, fs_info->extent_root,
166 &fs_info->pinned_extents);
168 free_extent_buffer(root->commit_root);
169 root->commit_root = NULL;
170 fs_info->running_transaction = NULL;
171 fs_info->last_trans_committed = transid;