common/nvme: reset def_adrfam for ipv4 case

When NVMET_TRTYPES specifies multiple transport types, blktests runs
each test case in the nvme group for each of the specified transport
types. When a test case is run for "fc" transport, it succeeds. However,
when following transport is "tcp" or "rdma", the test case fails.

This failure happens because the run for "fc" transport overrides the
global variable 'def_adrfam' with the value "fc". 'def_adrfam' is
initialized with "ipv4" when "common/nvme" is loaded, and it was assumed
that this value was not reused after the overwrite. However, since the
commit a16ac8e ("nvme/{002-031,033-038,040-045,047,048}: support
NMVET_TRTYPES"), the overwritten 'def_adrfam' is reused for other
transport types and the value "fc" causes failure for "tcp" or "rdma"
transports.

To ensure that 'def_adrfam' has correct values for "tcp" and "rdma"
transports even after test case runs for "fc" transport, initialize
the 'def_adrfam' with the value "ipv4". For the completeness, set "ipv4"
to 'def_adrfam' also when "nvme_adrfam" is specified.

Fixes: a16ac8e ("nvme/{002-031,033-038,040-045,047,048}: support NMVET_TRTYPES")
Link: #217
Signed-off-by: Daniel Wagner <[email protected]>
Signed-off-by: Shin'ichiro Kawasaki <[email protected]>

Author: igaw

common/nvme

@@ -1190,6 +1190,7 @@ _nvme_requires() {
 		_have_driver nvme-tcp
 		_have_driver nvmet-tcp
 		_have_configfs
+		def_adrfam="ipv4"
 		;;
 	rdma)
 		_have_driver nvme-rdma
@@ -1201,6 +1202,7 @@ _nvme_requires() {
 		else
 			_have_driver siw
 		fi
+		def_adrfam="ipv4"
 		;;
 	fc)
 		_have_driver nvme-fc
@@ -1217,7 +1219,8 @@ _nvme_requires() {
 			def_adrfam="ipv6"
 			;;
 		ipv4)
-			;; # was already set
+			def_adrfam="ipv4"
+			;;
 		fc)
 			def_adrfam="fc"
 			;;