Re: [PATCH 02/16] hw/block/nvme: add mapping helpers

[Klaus Jensen <its@irrelevant.dk>]

On Jul 29 14:51, Andrzej Jakowski wrote:
> On 7/29/20 2:24 PM, Klaus Jensen wrote:
> > On Jul 29 13:40, Andrzej Jakowski wrote:
> >> On 7/20/20 4:37 AM, Klaus Jensen wrote:
> >>> From: Klaus Jensen <k.jensen@samsung.com>
> >>>
> >>> Add nvme_map_addr, nvme_map_addr_cmb and nvme_addr_to_cmb helpers and
> >>> use them in nvme_map_prp.
> >>>
> >>> This fixes a bug where in the case of a CMB transfer, the device would
> >>> map to the buffer with a wrong length.
> >>>
> >>> Fixes: b2b2b67a00574 ("nvme: Add support for Read Data and Write Data in CMBs.")
> >>> Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
> >>> ---
> >>>  hw/block/nvme.c       | 109 +++++++++++++++++++++++++++++++++++-------
> >>>  hw/block/trace-events |   2 +
> >>>  2 files changed, 94 insertions(+), 17 deletions(-)
> >>>
> >>> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> >>> index 4d7b730a62b6..9b1a080cdc70 100644
> >>> --- a/hw/block/nvme.c
> >>> +++ b/hw/block/nvme.c
> >>> @@ -270,20 +338,27 @@ static uint16_t nvme_map_prp(QEMUSGList *qsg, QEMUIOVector *iov, uint64_t prp1,
> >>>          } else {
> >>>              if (unlikely(prp2 & (n->page_size - 1))) {
> >>>                  trace_pci_nvme_err_invalid_prp2_align(prp2);
> >>> +                status = NVME_INVALID_FIELD | NVME_DNR;
> >>>                  goto unmap;
> >>>              }
> >>> -            if (qsg->nsg) {
> >>> -                qemu_sglist_add(qsg, prp2, len);
> >>> -            } else {
> >>> -                qemu_iovec_add(iov, (void *)&n->cmbuf[prp2 - n->ctrl_mem.addr], trans_len);
> >>> +            status = nvme_map_addr(n, qsg, iov, prp2, len);
> >>> +            if (status) {
> >>> +                goto unmap;
> >>>              }
> >>>          }
> >>>      }
> >>>      return NVME_SUCCESS;
> >>>  
> >>> - unmap:
> >>> -    qemu_sglist_destroy(qsg);
> >>> -    return NVME_INVALID_FIELD | NVME_DNR;
> >>> +unmap:
> >>> +    if (iov && iov->iov) {
> >>> +        qemu_iovec_destroy(iov);
> >>> +    }
> >>> +
> >>> +    if (qsg && qsg->sg) {
> >>> +        qemu_sglist_destroy(qsg);
> >>> +    }
> >>> +
> >>> +    return status;
> >>
> >> I think it would make sense to move whole unmap block to a separate function.
> >> That function could be called from here and after completing IO and would contain
> >> unified deinitialization block - so no code repetitions would be necessary.
> >> Other than that it looks good to me. Thx!
> >>
> >> Reviewed-by: Andrzej Jakowski <andrzej.jakowski@linux.intel.com>
> >>
> >  
> > Hi Andrzej,
> > 
> > Thanks for the review :)
> > 
> > Yes, this is done in a later patch ("hw/block/nvme: consolidate qsg/iov
> > clearing"), but kept here to reduce churn.
> > 
> Yep, noticed that after sending email :)
> Do you plan to submit second version of these patches incorporating some
> of the feedback?
> 

Yes, so you can defer your reviews for v2 ;)