"Darrick J. Wong" <djwong@xxxxxxxxxx> writes:
> On Fri, Oct 25, 2024 at 09:15:53AM +0530, Ritesh Harjani (IBM) wrote:
>> iomap will not return -ENOTBLK in case of dio atomic writes. But let's
>> also add a WARN_ON_ONCE and return -EIO as a safety net.
>>
>> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
>> ---
>> fs/ext4/file.c | 10 +++++++++-
>> 1 file changed, 9 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
>> index f9516121a036..af6ebd0ac0d6 100644
>> --- a/fs/ext4/file.c
>> +++ b/fs/ext4/file.c
>> @@ -576,8 +576,16 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
>> iomap_ops = &ext4_iomap_overwrite_ops;
>> ret = iomap_dio_rw(iocb, from, iomap_ops, &ext4_dio_write_ops,
>> dio_flags, NULL, 0);
>> - if (ret == -ENOTBLK)
>> + if (ret == -ENOTBLK) {
>> ret = 0;
>> + /*
>> + * iomap will never return -ENOTBLK if write fails for atomic
>> + * write. But let's just add a safety net.
>
> I think it can if the pagecache invalidation fails, so you really do
> need the safety net.
Ah, right! So in that case I should remove WARN_ON_ONCE and correct
the comment too.
> I suspect that the xfs version of this series
> needs it too, though it may have fallen out?
>
I think so yes. Looks like it got missed.
> Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> --D
>
Thanks for pointing that out.
-ritesh
>> + */
>> + if (WARN_ON_ONCE(iocb->ki_flags & IOCB_ATOMIC))
>> + ret = -EIO;
>> + }
>> +
>> if (extend) {
>> /*
>> * We always perform extending DIO write synchronously so by
>> --
>> 2.46.0
>>
>>
