ext4: use transaction reservation for extent conversion in ext4_end_io
Later we would like to clear PageWriteback bit only after extent conversion from unwritten to written extents is performed. However it is not possible to start a transaction after PageWriteback is set because that violates lock ordering (and is easy to deadlock). So we have to reserve a transaction before locking pages and sending them for IO and later we use the transaction for extent conversion from ext4_end_io(). Reviewed-by:Zheng Liu <wenqing.lz@taobao.com> Signed-off-by:
Jan Kara <jack@suse.cz> Signed-off-by:
"Theodore Ts'o" <tytso@mit.edu>
parent
3613d228