Commit 2382c5cc authored Feb 22, 2013 by Liu Bo Committed by Josef Bacik Feb 26, 2013

Btrfs: use reserved space for creating a snapshot



While inserting dir index and updating inode for a snapshot, we'd
add delayed items which consume trans->block_rsv, if we don't have
any space reserved in this trans handle, we either just return or
reserve space again.

But before creating pending snapshots during committing transaction,
we've done a release on this trans handle, so we don't have space reserved
in it at this stage.

What we're using is block_rsv of pending snapshots which has already
reserved well enough space for both inserting dir index and updating
inode, so we need to set trans handle to indicate that we have space
now.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

parent a81cb9a2

fs/btrfs/transaction.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1123,6 +1123,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,

		rsv = trans->block_rsv;
		trans->block_rsv = &pending->block_rsv;
		trans->bytes_reserved = trans->block_rsv->reserved;

		dentry = pending->dentry;
		parent = dget_parent(dentry);
		@@ -1276,6 +1277,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
		fail:
		dput(parent);
		trans->block_rsv = rsv;
		trans->bytes_reserved = 0;
		no_free_objectid:
		kfree(new_root_item);
		root_item_alloc_fail:

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