Re: [PATCH for-next v5 4/6] RDMA-rxe: Isolate mr code from atomic_write_reply()

[Jason Gunthorpe <jgg@nvidia.com>]

On Tue, Jan 17, 2023 at 11:04:29AM -0600, Bob Pearson wrote:
> On 1/17/23 10:59, Jason Gunthorpe wrote:
> > On Tue, Jan 17, 2023 at 10:57:31AM -0600, Bob Pearson wrote:
> > 
> >>>> -	dst = iova_to_vaddr(mr, qp->resp.va + qp->resp.offset, payload);
> >>>> -	/* check vaddr is 8 bytes aligned. */
> >>>> -	if (!dst || (uintptr_t)dst & 7)
> >>>> -		return RESPST_ERR_MISALIGNED_ATOMIC;
> >>>> +	if (res->replay)
> >>>> +		return RESPST_ACKNOWLEDGE;
> >>>>  
> >>>> -	/* Do atomic write after all prior operations have completed */
> >>>> -	smp_store_release(dst, src);
> >>>> +	mr = qp->resp.mr;
> >>>> +	value = *(u64 *)payload_addr(pkt);
> >>>> +	iova = qp->resp.va + qp->resp.offset;
> >>>>  
> >>>> -	/* decrease resp.resid to zero */
> >>>> -	qp->resp.resid -= sizeof(payload);
> >>>> +#if defined CONFIG_64BIT
> >>>
> >>> Shouldn't need a #ifdef here
> >>
> >> This avoids a new special error (i.e. NOT_64_bit) and makes it clear we
> >> won't call the code in mr.
> > 
> > ? That doesn't seem right
> 
> that was the -3 of the -1, -2, -3 that we just fixed. there are three error paths out
> of this state and we need a way to get to them. The #ifdef provides
> that third path.

I feel like it should be solvable without this ifdef though

Jason