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);
29 if (fs_info->transaction_aborted)
30 return ERR_PTR(-EROFS);
33 return ERR_PTR(-ENOMEM);
34 if (root->commit_root) {
35 error("commit_root aleady set when starting transaction");
37 return ERR_PTR(-EINVAL);
39 if (fs_info->running_transaction) {
40 error("attempt to start transaction over already running one");
42 return ERR_PTR(-EINVAL);
45 fs_info->running_transaction = h;
46 fs_info->generation++;
47 h->transid = fs_info->generation;
48 h->blocks_reserved = num_blocks;
49 root->last_trans = h->transid;
50 root->commit_root = root->node;
51 extent_buffer_get(root->node);
56 static int update_cowonly_root(struct btrfs_trans_handle *trans,
57 struct btrfs_root *root)
61 struct btrfs_root *tree_root = root->fs_info->tree_root;
63 btrfs_write_dirty_block_groups(trans, root);
65 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
66 if (old_root_bytenr == root->node->start)
68 btrfs_set_root_bytenr(&root->root_item,
70 btrfs_set_root_generation(&root->root_item,
72 root->root_item.level = btrfs_header_level(root->node);
73 ret = btrfs_update_root(trans, tree_root,
77 btrfs_write_dirty_block_groups(trans, root);
82 int commit_tree_roots(struct btrfs_trans_handle *trans,
83 struct btrfs_fs_info *fs_info)
85 struct btrfs_root *root;
86 struct list_head *next;
87 struct extent_buffer *eb;
90 if (fs_info->readonly)
93 eb = fs_info->tree_root->node;
94 extent_buffer_get(eb);
95 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
96 free_extent_buffer(eb);
100 while(!list_empty(&fs_info->dirty_cowonly_roots)) {
101 next = fs_info->dirty_cowonly_roots.next;
103 root = list_entry(next, struct btrfs_root, dirty_list);
104 update_cowonly_root(trans, root);
105 free_extent_buffer(root->commit_root);
106 root->commit_root = NULL;
112 int __commit_transaction(struct btrfs_trans_handle *trans,
113 struct btrfs_root *root)
117 struct btrfs_fs_info *fs_info = root->fs_info;
118 struct extent_buffer *eb;
119 struct extent_io_tree *tree = &fs_info->extent_cache;
123 ret = find_first_extent_bit(tree, 0, &start, &end,
127 while(start <= end) {
128 eb = find_first_extent_buffer(tree, start);
129 BUG_ON(!eb || eb->start != start);
130 ret = write_tree_block(trans, fs_info, eb);
133 clear_extent_buffer_dirty(eb);
134 free_extent_buffer(eb);
140 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
141 struct btrfs_root *root)
143 u64 transid = trans->transid;
145 struct btrfs_fs_info *fs_info = root->fs_info;
147 if (trans->fs_info->transaction_aborted)
150 if (root->commit_root == root->node)
152 if (root == root->fs_info->tree_root)
154 if (root == root->fs_info->chunk_root)
157 free_extent_buffer(root->commit_root);
158 root->commit_root = NULL;
160 btrfs_set_root_bytenr(&root->root_item, root->node->start);
161 btrfs_set_root_generation(&root->root_item, trans->transid);
162 root->root_item.level = btrfs_header_level(root->node);
163 ret = btrfs_update_root(trans, root->fs_info->tree_root,
164 &root->root_key, &root->root_item);
167 ret = commit_tree_roots(trans, fs_info);
169 ret = __commit_transaction(trans, root);
171 write_ctree_super(trans, fs_info);
172 btrfs_finish_extent_commit(trans, fs_info->extent_root,
173 &fs_info->pinned_extents);
175 free_extent_buffer(root->commit_root);
176 root->commit_root = NULL;
177 fs_info->running_transaction = NULL;
178 fs_info->last_trans_committed = transid;
182 void btrfs_abort_transaction(struct btrfs_trans_handle *trans, int error)
184 trans->fs_info->transaction_aborted = error;