Re: [PATCH v6 18/42] nvme: support identify namespace descriptor list

[Maxim Levitsky]

On Mon, 2020-03-16 at 07:29 -0700, Klaus Jensen wrote:
> From: Klaus Jensen <address@hidden>
> 
> Since we are not providing the NGUID or EUI64 fields, we must support
> the Namespace UUID. We do not have any way of storing a persistent
> unique identifier, so conjure up a UUID that is just the namespace id.
> 
> Signed-off-by: Klaus Jensen <address@hidden>
> ---
>  hw/block/nvme.c       | 38 ++++++++++++++++++++++++++++++++++++++
>  hw/block/trace-events |  1 +
>  2 files changed, 39 insertions(+)
> 
> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> index 16de3ca1c5d5..007f8817f101 100644
> --- a/hw/block/nvme.c
> +++ b/hw/block/nvme.c
> @@ -942,6 +942,42 @@ static uint16_t nvme_identify_nslist(NvmeCtrl *n, 
> NvmeIdentify *c)
>      return ret;
>  }
>  
> +static uint16_t nvme_identify_ns_descr_list(NvmeCtrl *n, NvmeIdentify *c)
> +{
> +    uint32_t nsid = le32_to_cpu(c->nsid);
> +    uint64_t prp1 = le64_to_cpu(c->prp1);
> +    uint64_t prp2 = le64_to_cpu(c->prp2);
> +
> +    void *list;
> +    uint16_t ret;
> +    NvmeIdNsDescr *ns_descr;
> +
> +    trace_nvme_dev_identify_ns_descr_list(nsid);
> +
> +    if (unlikely(nsid == 0 || nsid > n->num_namespaces)) {
> +        trace_nvme_dev_err_invalid_ns(nsid, n->num_namespaces);
> +        return NVME_INVALID_NSID | NVME_DNR;
> +    }
> +
> +    list = g_malloc0(NVME_IDENTIFY_DATA_SIZE);
> +    ns_descr = list;
> +
> +    /*
> +     * Because the NGUID and EUI64 fields are 0 in the Identify Namespace 
> data
> +     * structure, a Namespace UUID (nidt = 0x3) must be reported in the
> +     * Namespace Identification Descriptor. Add a very basic Namespace UUID
> +     * here.
> +     */
> +    ns_descr->nidt = NVME_NIDT_UUID;
> +    ns_descr->nidl = NVME_NIDT_UUID_LEN;
> +    stl_be_p(ns_descr + sizeof(*ns_descr), nsid);
> +
> +    ret = nvme_dma_read_prp(n, (uint8_t *) list, NVME_IDENTIFY_DATA_SIZE, 
> prp1,
> +                            prp2);
> +    g_free(list);
> +    return ret;
> +}
> +
>  static uint16_t nvme_identify(NvmeCtrl *n, NvmeCmd *cmd)
>  {
>      NvmeIdentify *c = (NvmeIdentify *)cmd;
> @@ -953,6 +989,8 @@ static uint16_t nvme_identify(NvmeCtrl *n, NvmeCmd *cmd)
>          return nvme_identify_ctrl(n, c);
>      case NVME_ID_CNS_NS_ACTIVE_LIST:
>          return nvme_identify_nslist(n, c);
> +    case NVME_ID_CNS_NS_DESCR_LIST:
> +        return nvme_identify_ns_descr_list(n, c);
>      default:
>          trace_nvme_dev_err_invalid_identify_cns(le32_to_cpu(c->cns));
>          return NVME_INVALID_FIELD | NVME_DNR;
> diff --git a/hw/block/trace-events b/hw/block/trace-events
> index 13e2c71664f6..4cde0844ef64 100644
> --- a/hw/block/trace-events
> +++ b/hw/block/trace-events
> @@ -41,6 +41,7 @@ nvme_dev_del_cq(uint16_t cqid) "deleted completion queue, 
> sqid=%"PRIu16""
>  nvme_dev_identify_ctrl(void) "identify controller"
>  nvme_dev_identify_ns(uint32_t ns) "nsid %"PRIu32""
>  nvme_dev_identify_nslist(uint32_t ns) "nsid %"PRIu32""
> +nvme_dev_identify_ns_descr_list(uint32_t ns) "nsid %"PRIu32""
>  nvme_dev_getfeat(uint16_t cid, uint32_t fid) "cid %"PRIu16" fid 0x%"PRIx32""
>  nvme_dev_setfeat(uint16_t cid, uint32_t fid, uint32_t val) "cid %"PRIu16" 
> fid 0x%"PRIx32" val 0x%"PRIx32""
>  nvme_dev_getfeat_vwcache(const char* result) "get feature volatile write 
> cache, result=%s"

I think that we should add namespace uuid as a device parameter,
but its OK to do this in follow up patch.


Reviewed-by: Maxim Levitsky <address@hidden>

Best regards,
        Maxim Levitsky