Add test for ANA support

[hreinecke]

This small patchset adds a test for ANA support.
In doing so I also had to update the loop transport to enable more than one port.
But with that the issues mentioned in #113 are gone.

[kawasaki]

I tried to run tests with the changes on kernel version 6.2, and found that number of nvme test cases fail. For example, nvme/004 fail after the commit "nvme: enable ANA support".

nvme/004 (test nvme and nvmet UUID NS descriptors)           [failed]
    runtime  1.776s  ...  0.598s
    --- tests/nvme/004.out      2023-02-28 19:15:13.425727236 +0900
    +++ /home/shin/kts/kernel-test-suite/src/blktests/results/nodev/nvme/004.out.bad    2023-03-03 09:12:21.674526288 +0900
    @@ -1,5 +1,5 @@
     Running nvme/004
    -91fdba0d-f87b-4c25-b80f-db7be1418b9e
    -uuid.91fdba0d-f87b-4c25-b80f-db7be1418b9e
    +323d5abb-ff8e-4a12-99ad-128e15baef41
    +uuid.323d5abb-ff8e-4a12-99ad-128e15baef41
     NQN:blktests-subsystem-1 disconnected 1 controller(s)
     Test complete

[kawasaki]

As for the commit message of the second patch, it would be helpful to note that ANA is the acronym of Asymmetric Namespace Access that NVMe spec 1.4 introduced. (If I'm wrong, please correct me)

[kawasaki]

@hreinecke Thanks for the work. I reviewed and did test run, then made some feedbacks.

One more nit comment: the first three patches have various commit title prefixes "nvme", "nvme/rc" or "test/nvme". but they all modify test/nvme/rc file. The past commits do not have consistent prefix, but I think "nvme/rc" is the good choice.

[kawasaki]

@hreinecke Thanks for reworking the patches. Today, I ran the test case nvme/047 and observed it fails.

nvme/047 (test ANA optimized/transitioning/inaccessible support) [failed]
    runtime  44.260s  ...  45.509s
    --- tests/nvme/047.out      2023-03-07 10:07:13.131098972 +0900
    +++ /home/shin/kts/kernel-test-suite/src/blktests/results/nodev/nvme/047.out.bad    2023-03-07 13:54:20.111062268 +0900
    @@ -1,28 +1,71 @@
     Running nvme/047
     ANA state failover
    -1: grpid 1 state inaccessible
    -1: grpid 2 state optimized
    -2: grpid 1 state optimized
    -2: grpid 2 state inaccessible
    +cat: /sys/class/nvme/nvme7/nvme7n1/ana_grpid: No such file or directory
    ...
    (Run 'diff -u tests/nvme/047.out /home/shin/kts/kernel-test-suite/src/blktests/results/nodev/nvme/047.out.bad' to see the entire diff)

It looks that the sysfs attribute file ana_grpid is not found under /sys/class/nvme/nvmeX/nvmeXn1. I wonder what I'm missing to make the test case pass. I use kernel v6.2 and nvme-cli v2.2.1. Do I need any changes on top of these?

One nit comment is shellcheck warning. The change below for the last patch will avoid it.

diff --git a/tests/nvme/047 b/tests/nvme/047
index 0853d76..401f06e 100755
--- a/tests/nvme/047
+++ b/tests/nvme/047
@@ -58,7 +58,7 @@ execute_ana_test() {
        local port1=$3
        local port2=$4
        local mount_dir="/mnt/blktests"
-       local nproc=$(nproc)
+       local nproc
 
        switch_nvmet_anagroup "${port1}" "${port2}" "failover"
 
@@ -71,6 +71,7 @@ execute_ana_test() {
 
        _xfs_mkfs_and_mount "/dev/${nvmedev}n2" "${mount_dir}/ns2" >> "${FULL}" 2>&1
    
+       nproc=$(nproc)
        if (( nproc > 8 )); then
                nproc=8
        fi

[hreinecke]

And we can now retire this in favour of #146