Fix list-subsys filtering

[igaw]

Depends on: linux-nvme/libnvme#1022
Fixes: #2830

[igaw]

the documentation should also be updated, that the device name is optional and just a filter.

[martin-gpy]

I tried this from your fix-filter branches from both libnvme & nvme-cli, but do see some discrepancies in behavior here. For e.g. I have 5 NSs from 2 subsystems with one underlying path or controller each:

# nvme list
Node                  Generic               SN                   Model                                    Namespace  Usage                      Format           FW Rev
--------------------- --------------------- -------------------- ---------------------------------------- ---------- -------------------------- ---------------- --------
/dev/nvme1n1          /dev/ng1n1            81CYrBSoKGRJAAAAAAAN NetApp ONTAP Controller                  0x2          0.00   B /  10.74  GB    512   B +  0 B   9.18.1
/dev/nvme1n2          /dev/ng1n2            81CYrBSoKGRJAAAAAAAN NetApp ONTAP Controller                  0x1        330.56  MB /  10.74  GB      4 KiB +  0 B   9.18.1
/dev/nvme2n1          /dev/ng2n1            81CYrBSoKGRJAAAAAAAL NetApp ONTAP Controller                  0x2         20.48  kB /  10.74  GB      4 KiB +  0 B   9.18.1
/dev/nvme2n2          /dev/ng2n2            81CYrBSoKGRJAAAAAAAL NetApp ONTAP Controller                  0x3          0.00   B /  10.74  GB      4 KiB +  0 B   9.18.1
/dev/nvme2n3          /dev/ng2n3            81CYrBSoKGRJAAAAAAAL NetApp ONTAP Controller                  0x1        219.47  MB /  10.74  GB    512   B +  0 B   9.18.1

Now when I run list-subsys on a non-existent device from the 1st subsystem, I get the following blank output:

# nvme list-subsys /dev/nvme1n5
# echo $?
0

I get the same blank output for a non-existent device from a non-existent subsystem too:

# nvme list-subsys /dev/nvme3n1
# echo $?
0

So your patches are working as expected. But I see a problem when I run list-subsys on a valid device. For e.g.

# nvme list-subsys
nvme-subsys1 - NQN=nqn.1992-08.com.netapp:sn.48391d66c0a611ecaaa5d039ea165514:subsystem.subsys_CLIENT116_0
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:e6550026-173e-4959-ba74-be367844bd8a
\
 +- nvme1 tcp traddr=192.168.1.116,trsvcid=4420,host_traddr=192.168.1.6,src_addr=192.168.1.6 live

nvme-subsys2 - NQN=nqn.1992-08.com.netapp:sn.48391d66c0a611ecaaa5d039ea165514:subsystem.subsys_CLIENT116
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:e6550026-173e-4959-ba74-be367844bd8a
\
 +- nvme2 tcp traddr=192.168.1.116,trsvcid=4420,host_traddr=192.168.1.6,src_addr=192.168.1.6 live

No issues here when no devices are passed to list-subsys, as seen above. But when I run list-subsys on a valid device, I see the following discrepancy:

# nvme list-subsys /dev/nvme1n1
nvme-subsys1 - NQN=nqn.1992-08.com.netapp:sn.48391d66c0a611ecaaa5d039ea165514:subsystem.subsys_CLIENT116_0
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:e6550026-173e-4959-ba74-be367844bd8a
\
 +- nvme1 tcp traddr=192.168.1.116,trsvcid=4420,host_traddr=192.168.1.6,src_addr=192.168.1.6 live optimized

nvme-subsys2 - NQN=nqn.1992-08.com.netapp:sn.48391d66c0a611ecaaa5d039ea165514:subsystem.subsys_CLIENT116
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:e6550026-173e-4959-ba74-be367844bd8a
\

i.e. it mistakenly displays nvme-subsys2 as well above in addition to nvme-subsys1, which is wrong.

[igaw]

Thanks, I fixed the patch, works for me now:

# .build/nvme list-subsys  /dev/nvme0n1
nvme-subsys0 - NQN=nqn.1994-11.com.samsung:nvme:PM9B1:M.2:S67VNF0W218998
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:befdec4c-2234-11b2-a85c-ca77c773af36
\
 +- nvme0 pcie 0000:02:00.0 live

nvme-subsys1 - NQN=nqn.io-1
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:befdec4c-2234-11b2-a85c-ca77c773af36
\

after the update

# .build/nvme list-subsys /dev/nvme0n1
nvme-subsys0 - NQN=nqn.1994-11.com.samsung:nvme:PM9B1:M.2:S67VNF0W218998
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:befdec4c-2234-11b2-a85c-ca77c773af36
\
 +- nvme0 pcie 0000:02:00.0 live