[dm-devel] [PATCH 2/2] libmultipath: add %L path wildcard for 64-bit hex LUN

[Benjamin Marzinski]

On Wed, Feb 09, 2022 at 08:47:13PM +0100, Steffen Maier wrote:
> Complements v0.6.0 commit
> 01ab2a468ea2 ("libmultipath: Add additional path wildcards") as well as
> ("libmultipath: support host adapter name lookup for s390x ccw bus").
> 
> With that we can easily get the full FCP addressing triplet
> (HBA, WWPN, FCPLUN) from multipath tools without additional tools
> and correlation:
> 
> $ multipathd -k'show paths format "%w|%a|%r|%L"'
> uuid                             |host adapter|target WWPN       |LUN hex
> 36005076400820293e8000000000000a0|0.0.5080    |0x500507680b25c449|0x00a0000000000000
> 36005076400820293e8000000000000a0|0.0.5080    |0x500507680b25c448|0x00a0000000000000
> 36005076400820293e8000000000000a0|0.0.50c0    |0x500507680b26c449|0x00a0000000000000
> 36005076400820293e8000000000000a0|0.0.50c0    |0x500507680b26c448|0x00a0000000000000
> 
> Likewise, add a field lun_hex for JSON path output.
> 
Reviewed-by: Benjamin Marzinski <bmarzins at redhat.com>
> Reviewed-by: Benjamin Block <bblock at linux.ibm.com>
> Signed-off-by: Steffen Maier <maier at linux.ibm.com>
> ---
>  libmultipath/print.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/libmultipath/print.c b/libmultipath/print.c
> index 221b515f23d3..4f6146e85fc9 100644
> --- a/libmultipath/print.c
> +++ b/libmultipath/print.c
> @@ -96,6 +96,7 @@
>  			     "            \"host_wwpn\" : \"%R\",\n" \
>  			     "            \"target_wwpn\" : \"%r\",\n" \
>  			     "            \"host_adapter\" : \"%a\",\n" \
> +			     "            \"lun_hex\" : \"%L\",\n" \
>  			     "            \"marginal_st\" : \"%M\""
>  
>  #define PROGRESS_LEN  10
> @@ -451,6 +452,24 @@ snprint_hcil (struct strbuf *buff, const struct path * pp)
>  			pp->sg_id.lun);
>  }
>  
> +
> +static int
> +snprint_path_lunhex (struct strbuf *buff, const struct path * pp)
> +{
> +	uint64_t lunhex = SCSI_INVALID_LUN, scsilun;
> +
> +	if (!pp || pp->sg_id.host_no < 0)
> +		return print_strbuf(buff, "0x%016" PRIx64, lunhex);
> +
> +	scsilun = pp->sg_id.lun;
> +	/* cf. Linux kernel function int_to_scsilun() */
> +	lunhex = ((scsilun & 0x000000000000ffffULL) << 48) |
> +		((scsilun & 0x00000000ffff0000ULL) << 16) |
> +		((scsilun & 0x0000ffff00000000ULL) >> 16) |
> +		((scsilun & 0xffff000000000000ULL) >> 48);
> +	return print_strbuf(buff, "0x%016" PRIx64, lunhex);
> +}
> +
>  static int
>  snprint_dev (struct strbuf *buff, const struct path * pp)
>  {
> @@ -842,6 +861,7 @@ static const struct path_data pd[] = {
>  	{'0', "failures",      snprint_path_failures},
>  	{'P', "protocol",      snprint_path_protocol},
>  	{'I', "init_st",       snprint_initialized},
> +	{'L', "LUN hex",       snprint_path_lunhex},
>  };
>  
>  static const struct pathgroup_data pgd[] = {
> -- 
> 2.27.0