ndctl-init-labels(1)

1NDCTL-INIT-LABELS(1)                                      NDCTL-INIT-LABELS(1)
2
3
4

NAME

6       ndctl-init-labels - initialize the label data area on a dimm or set of
7       dimms
8

SYNOPSIS

10       ndctl init-labels <nmem0> [<nmem1>..<nmemN>] [<options>]
11

DESCRIPTION

13       The namespace label area is a small persistent partition of capacity
14       available on some NVDIMM devices. The label area is used to provision
15       one, or more, namespaces from regions. Starting with v4.10 the kernel
16       will honor labels for sub-dividing PMEM if all the DIMMs in an
17       interleave set / region have a valid namespace index block.
18
19       This command can be used to initialize the namespace index block if it
20       is missing or reinitialize it if it is damaged. Note that
21       reinitialization effectively destroys all existing namespace labels on
22       the DIMM.
23

EXAMPLE

25       Find the DIMMs that comprise a given region:
26
27           # ndctl list -RD --region=region1
28           {
29             "dimms":[
30               {
31                 "dev":"nmem0",
32                 "id":"8680-56341200"
33               }
34             ],
35             "regions":[
36               {
37                 "dev":"region1",
38                 "size":268435456,
39                 "available_size":0,
40                 "type":"pmem",
41                 "mappings":[
42                   {
43                     "dimm":"nmem0",
44                     "offset":13958643712,
45                     "length":268435456
46                   }
47                 ]
48               }
49             ]
50           }
51
52       Disable that region so the DIMM label area can be written from
53       userspace:
54
55           # ndctl disable-region region1
56
57       Initialize labels:
58
59           # ndctl init-labels nmem0
60
61       Re-enable the region:
62
63           # ndctl enable-region region1
64
65       Create a namespace in that region:
66
67           # ndctl create-namespace --region=region1
68

OPTIONS

70       <memory device(s)>
71           A nmemX device name, or a dimm id number. Restrict the operation to
72           the specified dimm(s). The keyword all can be specified to indicate
73           the lack of any restriction, however this is the same as not
74           supplying a --dimm option at all.
75
76       -s, --size=
77           Limit the operation to the given number of bytes. A size of 0
78           indicates to operate over the entire label capacity.
79
80       -O, --offset=
81           Begin the operation at the given offset into the label area.
82
83       -b, --bus=
84           A bus id number, or a provider string (e.g. "ACPI.NFIT"). Restrict
85           the operation to the specified bus(es). The keyword all can be
86           specified to indicate the lack of any restriction, however this is
87           the same as not supplying a --bus option at all.
88
89       -v
90           Turn on verbose debug messages in the library (if ndctl was built
91           with logging and debug enabled).
92
93       -f, --force
94           Force initialization of the label space even if there appears to be
95           an existing / valid namespace index. Warning, this will destroy all
96           defined namespaces on the dimm.
97
98       -V, --label-version
99           Initialize with a specific version of labels from the namespace
100           label specification. Defaults to 1.1
101

COPYRIGHT

103       Copyright © 2016 - 2022, Intel Corporation. License GPLv2: GNU GPL
104       version 2 http://gnu.org/licenses/gpl.html. This is free software: you
105       are free to change and redistribute it. There is NO WARRANTY, to the
106       extent permitted by law.
107

NOTES

112        1. UEFI NVDIMM Label Protocol
113           http://www.uefi.org/sites/default/files/resources/UEFI_Spec_2_7.pdf
114
115
116
117                                  03/08/2022              NDCTL-INIT-LABELS(1)