Hi Jaegeuk, On 2017/6/25 0:25, Jaegeuk Kim wrote: > - punch_hole > - fill_zero > - f2fs_lock_op > - get_new_data_page > - lock_page > > - f2fs_write_data_pages > - lock_page > - do_write_data_page > - f2fs_lock_op
Good catch! With this implementation, page writeback can fail due to concurrent checkpoint, this will make fsync/atomic_commit which trigger synchronous write failed randomly. How about unifying the lock order in punch_hole as one in writepages for regular inode? We can add one more parameter in get_new_data_page to indicate whether callee needs to lock cp_rwsem. Thanks, > > Signed-off-by: Jaegeuk Kim <[email protected]> > --- > fs/f2fs/data.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 7d3af48d34a9..9141bd19a902 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -1404,8 +1404,9 @@ int do_write_data_page(struct f2fs_io_info *fio) > } > } > > - if (fio->need_lock == LOCK_REQ) > - f2fs_lock_op(fio->sbi); > + /* Deadlock due to between page->lock and f2fs_lock_op */ > + if (fio->need_lock == LOCK_REQ && !f2fs_trylock_op(fio->sbi)) > + return -EAGAIN; > > err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE); > if (err) >
