179154b1bSChris Mason #include <linux/module.h> 279154b1bSChris Mason #include <linux/fs.h> 379154b1bSChris Mason #include "ctree.h" 479154b1bSChris Mason #include "disk-io.h" 579154b1bSChris Mason #include "transaction.h" 679154b1bSChris Mason 778fae27eSChris Mason static int total_trans = 0; 879154b1bSChris Mason static void put_transaction(struct btrfs_transaction *transaction) 979154b1bSChris Mason { 1079154b1bSChris Mason transaction->use_count--; 1178fae27eSChris Mason if (transaction->use_count == 0) { 1278fae27eSChris Mason WARN_ON(total_trans == 0); 1378fae27eSChris Mason total_trans--; 1479154b1bSChris Mason kfree(transaction); 1579154b1bSChris Mason } 1678fae27eSChris Mason } 1779154b1bSChris Mason 1879154b1bSChris Mason static int join_transaction(struct btrfs_root *root) 1979154b1bSChris Mason { 2079154b1bSChris Mason struct btrfs_transaction *cur_trans; 2179154b1bSChris Mason cur_trans = root->fs_info->running_transaction; 2279154b1bSChris Mason if (!cur_trans) { 2379154b1bSChris Mason cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS); 2478fae27eSChris Mason total_trans++; 2579154b1bSChris Mason BUG_ON(!cur_trans); 2679154b1bSChris Mason root->fs_info->running_transaction = cur_trans; 2779154b1bSChris Mason cur_trans->num_writers = 0; 2879154b1bSChris Mason cur_trans->transid = root->root_key.offset + 1; 2979154b1bSChris Mason init_waitqueue_head(&cur_trans->writer_wait); 3079154b1bSChris Mason init_waitqueue_head(&cur_trans->commit_wait); 3179154b1bSChris Mason cur_trans->in_commit = 0; 32d5719762SChris Mason cur_trans->use_count = 1; 3379154b1bSChris Mason cur_trans->commit_done = 0; 3479154b1bSChris Mason } 3579154b1bSChris Mason cur_trans->num_writers++; 3679154b1bSChris Mason return 0; 3779154b1bSChris Mason } 3879154b1bSChris Mason 3979154b1bSChris Mason struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 4079154b1bSChris Mason int num_blocks) 4179154b1bSChris Mason { 4279154b1bSChris Mason struct btrfs_trans_handle *h = kmalloc(sizeof(*h), GFP_NOFS); 4379154b1bSChris Mason int ret; 4479154b1bSChris Mason 4579154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 4679154b1bSChris Mason ret = join_transaction(root); 4779154b1bSChris Mason BUG_ON(ret); 4879154b1bSChris Mason h->transid = root->fs_info->running_transaction->transid; 4979154b1bSChris Mason h->transaction = root->fs_info->running_transaction; 5079154b1bSChris Mason h->blocks_reserved = num_blocks; 5179154b1bSChris Mason h->blocks_used = 0; 5279154b1bSChris Mason root->fs_info->running_transaction->use_count++; 5379154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 5479154b1bSChris Mason return h; 5579154b1bSChris Mason } 5679154b1bSChris Mason 5779154b1bSChris Mason int btrfs_end_transaction(struct btrfs_trans_handle *trans, 5879154b1bSChris Mason struct btrfs_root *root) 5979154b1bSChris Mason { 6079154b1bSChris Mason struct btrfs_transaction *cur_trans; 6179154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 6279154b1bSChris Mason cur_trans = root->fs_info->running_transaction; 63d5719762SChris Mason WARN_ON(cur_trans->num_writers < 1); 6479154b1bSChris Mason if (waitqueue_active(&cur_trans->writer_wait)) 6579154b1bSChris Mason wake_up(&cur_trans->writer_wait); 6679154b1bSChris Mason cur_trans->num_writers--; 6779154b1bSChris Mason put_transaction(cur_trans); 6879154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 6979154b1bSChris Mason kfree(trans); 7079154b1bSChris Mason return 0; 7179154b1bSChris Mason } 7279154b1bSChris Mason 7379154b1bSChris Mason 7479154b1bSChris Mason int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, 7579154b1bSChris Mason struct btrfs_root *root) 7679154b1bSChris Mason { 77d98237b3SChris Mason filemap_write_and_wait(root->fs_info->btree_inode->i_mapping); 7879154b1bSChris Mason return 0; 7979154b1bSChris Mason } 8079154b1bSChris Mason 8179154b1bSChris Mason int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans, 8279154b1bSChris Mason struct btrfs_root *root) 8379154b1bSChris Mason { 8479154b1bSChris Mason int ret; 8579154b1bSChris Mason u64 old_extent_block; 8679154b1bSChris Mason struct btrfs_fs_info *fs_info = root->fs_info; 8779154b1bSChris Mason struct btrfs_root *tree_root = fs_info->tree_root; 8879154b1bSChris Mason struct btrfs_root *extent_root = fs_info->extent_root; 8979154b1bSChris Mason struct btrfs_root *inode_root = fs_info->inode_root; 9079154b1bSChris Mason 9179154b1bSChris Mason btrfs_set_root_blocknr(&inode_root->root_item, 9279154b1bSChris Mason inode_root->node->b_blocknr); 9379154b1bSChris Mason ret = btrfs_update_root(trans, tree_root, 9479154b1bSChris Mason &inode_root->root_key, 9579154b1bSChris Mason &inode_root->root_item); 9679154b1bSChris Mason BUG_ON(ret); 9779154b1bSChris Mason while(1) { 9879154b1bSChris Mason old_extent_block = btrfs_root_blocknr(&extent_root->root_item); 9979154b1bSChris Mason if (old_extent_block == extent_root->node->b_blocknr) 10079154b1bSChris Mason break; 10179154b1bSChris Mason btrfs_set_root_blocknr(&extent_root->root_item, 10279154b1bSChris Mason extent_root->node->b_blocknr); 10379154b1bSChris Mason ret = btrfs_update_root(trans, tree_root, 10479154b1bSChris Mason &extent_root->root_key, 10579154b1bSChris Mason &extent_root->root_item); 10679154b1bSChris Mason BUG_ON(ret); 10779154b1bSChris Mason } 10879154b1bSChris Mason return 0; 10979154b1bSChris Mason } 11079154b1bSChris Mason 11179154b1bSChris Mason static int wait_for_commit(struct btrfs_root *root, 11279154b1bSChris Mason struct btrfs_transaction *commit) 11379154b1bSChris Mason { 11479154b1bSChris Mason DEFINE_WAIT(wait); 11579154b1bSChris Mason while(!commit->commit_done) { 11679154b1bSChris Mason prepare_to_wait(&commit->commit_wait, &wait, 11779154b1bSChris Mason TASK_UNINTERRUPTIBLE); 11879154b1bSChris Mason if (commit->commit_done) 11979154b1bSChris Mason break; 12079154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 12179154b1bSChris Mason schedule(); 12279154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 12379154b1bSChris Mason } 12479154b1bSChris Mason finish_wait(&commit->commit_wait, &wait); 12579154b1bSChris Mason return 0; 12679154b1bSChris Mason } 12779154b1bSChris Mason 12879154b1bSChris Mason int btrfs_commit_transaction(struct btrfs_trans_handle *trans, 12979154b1bSChris Mason struct btrfs_root *root) 13079154b1bSChris Mason { 13179154b1bSChris Mason int ret = 0; 13278fae27eSChris Mason struct buffer_head *snap; 13379154b1bSChris Mason struct btrfs_key snap_key; 13479154b1bSChris Mason struct btrfs_transaction *cur_trans; 13579154b1bSChris Mason DEFINE_WAIT(wait); 13679154b1bSChris Mason 13779154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 13879154b1bSChris Mason if (trans->transaction->in_commit) { 13979154b1bSChris Mason cur_trans = trans->transaction; 14079154b1bSChris Mason trans->transaction->use_count++; 14179154b1bSChris Mason btrfs_end_transaction(trans, root); 14279154b1bSChris Mason ret = wait_for_commit(root, cur_trans); 14379154b1bSChris Mason BUG_ON(ret); 14479154b1bSChris Mason put_transaction(cur_trans); 14579154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 14679154b1bSChris Mason return 0; 14779154b1bSChris Mason } 14879154b1bSChris Mason while (trans->transaction->num_writers > 1) { 14979154b1bSChris Mason prepare_to_wait(&trans->transaction->writer_wait, &wait, 15079154b1bSChris Mason TASK_UNINTERRUPTIBLE); 15179154b1bSChris Mason if (trans->transaction->num_writers <= 1) 15279154b1bSChris Mason break; 15379154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 15479154b1bSChris Mason schedule(); 15579154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 15679154b1bSChris Mason } 15779154b1bSChris Mason finish_wait(&trans->transaction->writer_wait, &wait); 15879154b1bSChris Mason 159d5719762SChris Mason if (root->node != root->commit_root) { 16079154b1bSChris Mason memcpy(&snap_key, &root->root_key, sizeof(snap_key)); 16179154b1bSChris Mason root->root_key.offset++; 162d5719762SChris Mason } 163d5719762SChris Mason 16479154b1bSChris Mason 16579154b1bSChris Mason if (btrfs_root_blocknr(&root->root_item) != root->node->b_blocknr) { 16679154b1bSChris Mason btrfs_set_root_blocknr(&root->root_item, root->node->b_blocknr); 16779154b1bSChris Mason ret = btrfs_insert_root(trans, root->fs_info->tree_root, 16879154b1bSChris Mason &root->root_key, &root->root_item); 16979154b1bSChris Mason BUG_ON(ret); 17079154b1bSChris Mason } 17179154b1bSChris Mason 17279154b1bSChris Mason ret = btrfs_commit_tree_roots(trans, root); 17379154b1bSChris Mason BUG_ON(ret); 17479154b1bSChris Mason 17578fae27eSChris Mason cur_trans = root->fs_info->running_transaction; 17678fae27eSChris Mason root->fs_info->running_transaction = NULL; 17778fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 17878fae27eSChris Mason 17979154b1bSChris Mason ret = btrfs_write_and_wait_transaction(trans, root); 18079154b1bSChris Mason BUG_ON(ret); 18179154b1bSChris Mason 18279154b1bSChris Mason write_ctree_super(trans, root); 18378fae27eSChris Mason btrfs_finish_extent_commit(trans, root); 18478fae27eSChris Mason mutex_lock(&root->fs_info->trans_mutex); 18579154b1bSChris Mason put_transaction(cur_trans); 18678fae27eSChris Mason put_transaction(cur_trans); 18778fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 18879154b1bSChris Mason kfree(trans); 18979154b1bSChris Mason 19079154b1bSChris Mason if (root->node != root->commit_root) { 19179154b1bSChris Mason trans = btrfs_start_transaction(root, 1); 19278fae27eSChris Mason snap = root->commit_root; 19379154b1bSChris Mason root->commit_root = root->node; 19479154b1bSChris Mason get_bh(root->node); 19579154b1bSChris Mason ret = btrfs_drop_snapshot(trans, root, snap); 19679154b1bSChris Mason BUG_ON(ret); 19779154b1bSChris Mason 19879154b1bSChris Mason ret = btrfs_del_root(trans, root->fs_info->tree_root, 19979154b1bSChris Mason &snap_key); 20078fae27eSChris Mason BUG_ON(ret); root->fs_info->generation = root->root_key.offset + 1; ret = btrfs_end_transaction(trans, root); BUG_ON(ret); 20178fae27eSChris Mason printk("at free, total trans %d\n", total_trans); 20279154b1bSChris Mason } 20379154b1bSChris Mason 20479154b1bSChris Mason return ret; 20579154b1bSChris Mason } 20679154b1bSChris Mason 207