• Maximilian Heyne's avatar
    fs: fix lost error code in dio_complete · 55eb06b7
    Maximilian Heyne authored
    commit 41e817bca3acd3980efe5dd7d28af0e6f4ab9247 upstream.
    
    commit e2592217 ("fs: simplify the
    generic_write_sync prototype") reworked callers of generic_write_sync(),
    and ended up dropping the error return for the directio path. Prior to
    that commit, in dio_complete(), an error would be bubbled up the stack,
    but after that commit, errors passed on to dio_complete were eaten up.
    
    This was reported on the list earlier, and a fix was proposed in
    https://lore.kernel.org/lkml/20160921141539.GA17898@infradead.org/, but
    never followed up with.  We recently hit this bug in our testing where
    fencing io errors, which were previously erroring out with EIO, were
    being returned as success operations after this commit.
    
    The fix proposed on the list earlier was a little short -- it would have
    still called generic_write_sync() in case `ret` already contained an
    error. This fix ensures generic_write_sync() is only called when there's
    no pending error in the write. Additionally, transferred is replaced
    with ret to bring this code in line with other callers.
    
    Fixes: e2592217 ("fs: simplify the generic_write_sync prototype")
    Reported-by: 's avatarRavi Nankani <rnankani@amazon.com>
    Signed-off-by: 's avatarMaximilian Heyne <mheyne@amazon.de>
    Reviewed-by: 's avatarChristoph Hellwig <hch@lst.de>
    CC: Torsten Mehlan <tomeh@amazon.de>
    CC: Uwe Dannowski <uwed@amazon.de>
    CC: Amit Shah <aams@amazon.de>
    CC: David Woodhouse <dwmw@amazon.co.uk>
    CC: stable@vger.kernel.org
    Signed-off-by: 's avatarJens Axboe <axboe@kernel.dk>
    Signed-off-by: 's avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    55eb06b7