io_uring/rw: fix error'ed retry return values

Kernel test robot reports that we test negativity of an unsigned in
io_fixup_rw_res() after a recent change, which masks error codes and
messes up the return value in case I/O is re-retried and failed with
an error.

Fixes: 4d9cb92ca41dd ("io_uring/rw: fix short rw error handling")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/9754a0970af1861e7865f9014f735c70dc60bf79.1663071587.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
1 file changed