On Wed, Nov 10, 2021 at 6:40 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > On Fri, 5 Nov 2021 at 08:44, Hao Peng <flyingpenghao@xxxxxxxxx> wrote: > > > > On Thu, Nov 4, 2021 at 8:18 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > > > > > On Wed, 3 Nov 2021 at 02:15, Peng Hao <flyingpenghao@xxxxxxxxx> wrote: > > > > > > > > The 'written' that generic_file_direct_write return through > > > > filemap_write_and_wait_range is not necessarily sequential, > > > > and its iocb->ki_pos has not been updated. > > > > > > I don't see the bug, but maybe I'm missing something. Can you please > > > explain in detail? > > > > > I think we shouldn't add "written" to variable pos. > > generic_file_direct_write: > > .... > > written = filemap_write_and_wait_range(mapping, pos, > > pos + write_len - 1); > > if (written) //the number of writes here reflects the > > amount of writeback data > > No. It's actually an error code in this case. > > It is confusing, though, so I guess cleaning this up (e.g. rename > "written" to "retval") would make sense. > oh,sorry. I misunderstood. I should deeply analyze the function called below. > Thanks, > Miklos
