> > > >> > >> Persistent backend setup requires some knowledge about nvdimm and ndctl > >> tool. Some users report they may struggle to gather these knowledge and > >> have difficulty to setup it properly. > >> > >> Here we provide two examples for persistent backend and gives the link > >> to ndctl. By doing so, user could try it directly and do more > >> investigation on persistent backend setup with ndctl. > >> > >> Signed-off-by: Wei Yang <richardw.y...@linux.intel.com> > >> --- > >> docs/nvdimm.txt | 28 ++++++++++++++++++++++++++++ > >> 1 file changed, 28 insertions(+) > >> > >> diff --git a/docs/nvdimm.txt b/docs/nvdimm.txt > >> index b531cacd35..baba7a940d 100644 > >> --- a/docs/nvdimm.txt > >> +++ b/docs/nvdimm.txt > >> @@ -171,6 +171,32 @@ guest software that this vNVDIMM device contains a > >> region that cannot > >> accept persistent writes. In result, for example, the guest Linux > >> NVDIMM driver, marks such vNVDIMM device as read-only. > >> > >> +Backend File Setup Example > >> +.......................... > >> + > >> +Here is two examples for how to setup these persistent backend on > >> +linux, which leverages the tool ndctl [3]. > >> + > >> +It is easy to setup DAX device backend file. > >> + > >> +A. DAX device > >> + > >> + ndctl create-namespace -f -e namespace0.0 -m devdax > >> + > >> +The /dev/dax0.0 could be used directly in "mem-path" option. > >> + > >> +For DAX file, it is more than creating the proper namespace. The > >> +block device should be partitioned and mounted (with dax option). > >> + > >> +B. DAX file > >> + > >> + ndctl create-namespace -f -e namespace0.0 -m fsdax > >> + (partition /dev/pmem0 with name pmem0p1) > >> + mount -o dax /dev/pmem0p1 /mnt > >> + (dd a file with proper size in /mnt) > > > >This is not clear to me. why 'dd' file is required in /mnt? > >You mean for creating a backend file? > > > > Yes, create a backend file. You need to give a file instead of a directory to > qemu command line. o.k
Thanks, Pankaj > > >> + > >> +Then the new file in /mnt could be used in "mem-path" option. > >> + > >> NVDIMM Persistence > >> ------------------ > >> > >> @@ -212,3 +238,5 @@ References > >> > >> https://www.snia.org/sites/default/files/technical_work/final/NVMProgrammingModel_v1.2.pdf > >> [2] Persistent Memory Development Kit (PMDK), formerly known as NVML > >> project, home page: > >> http://pmem.io/pmdk/ > >> +[3] ndctl-create-namespace - provision or reconfigure a namespace > >> + http://pmem.io/ndctl/ndctl-create-namespace.html > >> -- > > > >Looks good to me. Just a small comment above. > >Other than that: Reviewed-by: Pankaj Gupta <pagu...@redhat.com> > > > > Thanks > > >> 2.17.1 > >> > >> > >> > > -- > Wei Yang > Help you, Help me > >
