[PATCH] nvmet-tcp: fix data digest pointer calculation

[Sagi Grimberg]

>>>>>> diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
>>>>>> index 07ee347..d641bfa 100644
>>>>>> --- a/drivers/nvme/target/tcp.c
>>>>>> +++ b/drivers/nvme/target/tcp.c
>>>>>> @@ -702,7 +702,7 @@ static int nvmet_try_send_ddgst(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
>>>>>>    	struct nvmet_tcp_queue *queue = cmd->queue;
>>>>>>    	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
>>>>>>    	struct kvec iov = {
>>>>>> -		.iov_base = &cmd->exp_ddgst + cmd->offset,
>>>>>> +		.iov_base = (u8 *)&cmd->exp_ddgst + cmd->offset,
>>>>>
>>>>> Wouldn't be the better fix to divide cmd->offset by 4 instead of the
>>>>> casts?  I can fix this up inline if that is ok.
>>>>
>>>> Don't really mind, what makes it a better fix?
>>>
>>> I generally prefer to avoid casts as they paper over bugs.
>>
>> I'm fine either way.
> 
> cmd->offset can have value 0,1,2,3. cmd->offset / 4 will always be 0.
> If 2 bytes of digest are transmitted in the first call to kernel_sendmsg()
> then in the second call remaining 2 bytes has to be transmitted so data digest
> buffer pointer should increase by 2 bytes.

Right, so let's just change the cast to (void *). Varun, can you respin
the patches?