I haven't got a filesystem mounted using DAX yet, but I thought I might
as well send out the current patch against ktest for enabling persistent
memory. It's clearly *wrong*, but I do get a /dev/pmem0 device under
Linux once I add all the right config options. So it's a start, and
people who are deeper into this than I am can suggest things to do to
make it better.
diff --git a/boot.ktest b/boot.ktest
index 8b22e1d..7e7d252 100644
--- a/boot.ktest
+++ b/boot.ktest
@@ -5,6 +5,7 @@ require-lib tests/prelude.sh
config-mem 2G
config-scratch-devs 4G
config-scratch-devs 4G
+config-pmem-devs 4G
config-timeout 600000
main()
diff --git a/lib/libktest.sh b/lib/libktest.sh
index 7843088..ad1ea62 100644
--- a/lib/libktest.sh
+++ b/lib/libktest.sh
@@ -271,7 +271,7 @@ start_vm()
case $ktest_arch in
x86|x86_64)
- qemu_cmd+=(-cpu host -machine accel=kvm)
+ qemu_cmd+=(-cpu host -machine accel=kvm,nvdimm)
;;
mips)
qemu_cmd+=(-cpu 24Kf -machine malta)
@@ -283,7 +283,7 @@ start_vm()
esac
qemu_cmd+=( \
- -m "$ktest_mem" \
+ -m "$ktest_mem,slots=8,maxmem=1T" \
-smp "$ktest_cpus" \
-kernel "$ktest_kernel_binary/vmlinuz" \
-append "$(join_by " " ${kernelargs[@]})" \
@@ -316,6 +316,13 @@ start_vm()
disknr=$((disknr + 1))
}
+ qemu_pmem()
+ {
+ qemu_cmd+=(-object memory-backend-file,id=mem$disknr,share,"$1",align=128M)
+ qemu_cmd+=(-device nvdimm,memdev=mem$disknr,id=nv$disknr,label-size=2M)
+ disknr=$((disknr + 1))
+ }
+
qemu_disk file="$ktest_root_image",snapshot=on
for size in "${ktest_scratch_devs[@]}"; do
@@ -325,6 +332,13 @@ start_vm()
qemu_disk file="$file",cache=unsafe
done
+ for size in "${ktest_pmem_devs[@]}"; do
+ local file="$ktest_tmp/dev-$disknr"
+
+ fallocate -l "$size" "$file"
+ qemu_pmem mem-path="$file",size=$size
+ done
+
set|grep -vE '^[A-Z]' > "$ktest_tmp/env"
set +o errexit
diff --git a/lib/parse-test.sh b/lib/parse-test.sh
index 30b23ad..353d713 100644
--- a/lib/parse-test.sh
+++ b/lib/parse-test.sh
@@ -90,6 +90,11 @@ parse_test_deps()
ktest_scratch_devs+=("$1")
}
+ config-pmem-devs()
+ {
+ ktest_pmem_devs+=("$1")
+ }
+
config-image()
{
ktest_root_image=$1
