Re: [PATCH 10/16] hw/block/nvme: add check for mdts

[Minwoo Im <minwoo.im.dev@gmail.com>]

On 20-07-20 13:37:42, Klaus Jensen wrote:
> From: Klaus Jensen <k.jensen@samsung.com>
> 
> Add 'mdts' device parameter to control the Maximum Data Transfer Size of
> the controller and check that it is respected.
> 
> Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
> ---
>  hw/block/nvme.c       | 32 ++++++++++++++++++++++++++++++--
>  hw/block/nvme.h       |  1 +
>  hw/block/trace-events |  1 +
>  3 files changed, 32 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> index 35bc1a7b7e21..10fe53873ae9 100644
> --- a/hw/block/nvme.c
> +++ b/hw/block/nvme.c
> @@ -18,9 +18,10 @@
>   * Usage: add options:
>   *      -drive file=<file>,if=none,id=<drive_id>
>   *      -device nvme,drive=<drive_id>,serial=<serial>,id=<id[optional]>, \
> - *              cmb_size_mb=<cmb_size_mb[optional]>, \
> + *              [cmb_size_mb=<cmb_size_mb>,] \
>   *              [pmrdev=<mem_backend_file_id>,] \
> - *              max_ioqpairs=<N[optional]>
> + *              [max_ioqpairs=<N>,] \
> + *              [mdts=<N>]

Nitpick:
  cmb and ioqpairs-things could be in another thread. :)

>   *
>   * Note cmb_size_mb denotes size of CMB in MB. CMB is assumed to be at
>   * offset 0 in BAR2 and supports only WDS, RDS and SQS for now.
> @@ -553,6 +554,17 @@ static void nvme_clear_events(NvmeCtrl *n, uint8_t event_type)
>      }
>  }
>  
> +static inline uint16_t nvme_check_mdts(NvmeCtrl *n, size_t len)
> +{
> +    uint8_t mdts = n->params.mdts;
> +
> +    if (mdts && len > n->page_size << mdts) {
> +        return NVME_INVALID_FIELD | NVME_DNR;
> +    }
> +
> +    return NVME_SUCCESS;
> +}
> +
>  static inline uint16_t nvme_check_bounds(NvmeCtrl *n, NvmeNamespace *ns,
>                                           uint64_t slba, uint32_t nlb)
>  {
> @@ -646,6 +658,13 @@ static uint16_t nvme_rw(NvmeCtrl *n, NvmeNamespace *ns, NvmeCmd *cmd,
>  
>      trace_pci_nvme_rw(is_write ? "write" : "read", nlb, data_size, slba);
>  
> +    status = nvme_check_mdts(n, data_size);
> +    if (status) {
> +        trace_pci_nvme_err_mdts(nvme_cid(req), data_size);
> +        block_acct_invalid(blk_get_stats(n->conf.blk), acct);
> +        return status;
> +    }
> +
>      status = nvme_check_bounds(n, ns, slba, nlb);
>      if (status) {
>          trace_pci_nvme_err_invalid_lba_range(slba, nlb, ns->id_ns.nsze);
> @@ -938,6 +957,7 @@ static uint16_t nvme_get_log(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
>      uint32_t numdl, numdu;
>      uint64_t off, lpol, lpou;
>      size_t   len;
> +    uint16_t status;
>  
>      numdl = (dw10 >> 16);
>      numdu = (dw11 & 0xffff);
> @@ -953,6 +973,12 @@ static uint16_t nvme_get_log(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
>  
>      trace_pci_nvme_get_log(nvme_cid(req), lid, lsp, rae, len, off);
>  
> +    status = nvme_check_mdts(n, len);
> +    if (status) {
> +        trace_pci_nvme_err_mdts(nvme_cid(req), len);
> +        return status;
> +    }
> +
>      switch (lid) {
>      case NVME_LOG_ERROR_INFO:
>          return nvme_error_info(n, cmd, rae, len, off, req);
> @@ -2275,6 +2301,7 @@ static void nvme_init_ctrl(NvmeCtrl *n, PCIDevice *pci_dev)
>      id->ieee[0] = 0x00;
>      id->ieee[1] = 0x02;
>      id->ieee[2] = 0xb3;
> +    id->mdts = n->params.mdts;
>      id->ver = cpu_to_le32(NVME_SPEC_VER);
>      id->oacs = cpu_to_le16(0);
>  
> @@ -2394,6 +2421,7 @@ static Property nvme_props[] = {
>      DEFINE_PROP_UINT16("msix_qsize", NvmeCtrl, params.msix_qsize, 65),
>      DEFINE_PROP_UINT8("aerl", NvmeCtrl, params.aerl, 3),
>      DEFINE_PROP_UINT32("aer_max_queued", NvmeCtrl, params.aer_max_queued, 64),
> +    DEFINE_PROP_UINT8("mdts", NvmeCtrl, params.mdts, 7),
>      DEFINE_PROP_END_OF_LIST(),
>  };
>  
> diff --git a/hw/block/nvme.h b/hw/block/nvme.h
> index 5519b5cc7686..137cd8c2bf20 100644
> --- a/hw/block/nvme.h
> +++ b/hw/block/nvme.h
> @@ -11,6 +11,7 @@ typedef struct NvmeParams {
>      uint32_t cmb_size_mb;
>      uint8_t  aerl;
>      uint32_t aer_max_queued;
> +    uint8_t  mdts;
>  } NvmeParams;
>  
>  typedef struct NvmeAsyncEvent {
> diff --git a/hw/block/trace-events b/hw/block/trace-events
> index 6d0cd588c786..5d7d4679650b 100644
> --- a/hw/block/trace-events
> +++ b/hw/block/trace-events
> @@ -85,6 +85,7 @@ pci_nvme_mmio_shutdown_set(void) "shutdown bit set"
>  pci_nvme_mmio_shutdown_cleared(void) "shutdown bit cleared"
>  
>  # nvme traces for error conditions
> +pci_nvme_err_mdts(uint16_t cid, size_t len) "cid %"PRIu16" len %"PRIu64""
>  pci_nvme_err_invalid_dma(void) "PRP/SGL is too small for transfer size"
>  pci_nvme_err_invalid_prplist_ent(uint64_t prplist) "PRP list entry is null or not page aligned: 0x%"PRIx64""
>  pci_nvme_err_invalid_prp2_align(uint64_t prp2) "PRP2 is not page aligned: 0x%"PRIx64""
> -- 
> 2.27.0
> 
> 

Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>

Thanks,