From 5b21f2ed3f2947b5195b65c9fdbdd9e52904cc03 Mon Sep 17 00:00:00 2001 From: Zheng Yan Date: Fri, 26 Sep 2008 10:05:38 -0400 Subject: Btrfs: extent_map and data=ordered fixes for space balancing * Add an EXTENT_BOUNDARY state bit to keep the writepage code from merging data extents that are in the process of being relocated. This allows us to do accounting for them properly. * The balancing code relocates data extents indepdent of the underlying inode. The extent_map code was modified to properly account for things moving around (invalidating extent_map caches in the inode). * Don't take the drop_mutex in the create_subvol ioctl. It isn't required. * Fix walking of the ordered extent list to avoid races with sys_unlink * Change the lock ordering rules. Transaction start goes outside the drop_mutex. This allows btrfs_commit_transaction to directly drop the relocation trees. Signed-off-by: Chris Mason --- fs/btrfs/transaction.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'fs/btrfs/transaction.c') diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 656baefa525..8c83cf464c8 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -109,6 +109,7 @@ noinline int btrfs_record_root_in_trans(struct btrfs_root *root) spin_lock_init(&dirty->root->node_lock); spin_lock_init(&dirty->root->list_lock); mutex_init(&dirty->root->objectid_mutex); + mutex_init(&dirty->root->log_mutex); INIT_LIST_HEAD(&dirty->root->dead_list); dirty->root->node = root->commit_root; dirty->root->commit_root = NULL; @@ -590,13 +591,14 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root, root = dirty->latest_root; atomic_inc(&root->fs_info->throttles); - mutex_lock(&root->fs_info->drop_mutex); while(1) { trans = btrfs_start_transaction(tree_root, 1); + mutex_lock(&root->fs_info->drop_mutex); ret = btrfs_drop_snapshot(trans, dirty->root); if (ret != -EAGAIN) { break; } + mutex_unlock(&root->fs_info->drop_mutex); err = btrfs_update_root(trans, tree_root, @@ -608,10 +610,8 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root, ret = btrfs_end_transaction(trans, tree_root); BUG_ON(ret); - mutex_unlock(&root->fs_info->drop_mutex); btrfs_btree_balance_dirty(tree_root, nr); cond_resched(); - mutex_lock(&root->fs_info->drop_mutex); } BUG_ON(ret); atomic_dec(&root->fs_info->throttles); @@ -689,7 +689,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); key.objectid = objectid; - key.offset = 1; + key.offset = trans->transid; btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); old = btrfs_lock_root_node(root); -- cgit v1.2.3