SYNOPSIS
nvme id-ns <device> [-v | --vendor-specific] [-b | --raw-binary] [--namespace-id=<nsid> | -n <nsid>]
DESCRIPTION
For the NVMe device given, sends an identify namespace command and provides the result and returned structure.
The <device> parameter is mandatory and may be either the NVMe character device (ex: /dev/nvme0), or a namespace block device (ex: /dev/nvme0n1). If the character device is given, the '--namespace-id' option is mandatory, otherwise it will use the ns-id of the namespace for the block device you opened. For block devices, the ns-id used can be overridden with the same option.
On success, the structure may be returned in one of several ways depending on the option flags; the structure may be parsed by the program or the raw buffer may be printed to stdout.
OPTIONS
- -n <nsid>
- --namespace-id=<nsid>
-
Retrieve the identify namespace structure for the given nsid. This is required for the character devices, or overrides the block nsid if given.
- -b
- --raw-binary
-
Print the raw buffer to stdout. Structure is not parsed by program. This overrides the vendor specific and human readable options.
- -v
- --vendor-specific
-
In addition to parsing known fields, this option will dump the vendor specific region of the structure in hex with ascii interpretation.
- -H
- --human-readable
-
This option will parse and format many of the bit fields into human-readable formats.
EXAMPLES
-
Has the program interpret the returned buffer and display the known fields in a human readable format:
# nvme id-ns /dev/nvme0n1
-
If using the character device or overriding namespace id:
# nvme id-ns /dev/nvme0 -n 1 # nvme id-ns /dev/nvme0n1 -n 1 # nvme id-ns /dev/nvme0 --namespace-id=1
-
In addition to showing the known fields, have the program to display the vendor unique field:
# nvme id-ns /dev/nvme0n1 --vendor-specific # nvme id-ns /dev/nvme0n1 -v
The above will dump the 'vs' buffer in hex since it doesn’t know how to interpret it.
-
Have the program return the raw structure in binary:
# nvme id-ns /dev/nvme0n1 --raw-binary > id_ns.raw # nvme id-ns /dev/nvme0n1 -b > id_ns.raw
It is probably a bad idea to not redirect stdout when using this mode.
-
Alternatively you may want to send the data to another program that can parse the raw buffer.
# nvme id-ns /dev/nvme0n1 --raw-binary | nvme_parse_id_ns
The parse program in the above example can be a program that shows the structure in a way you like. The following program is such an example that will parse it and can accept the output through a pipe, '|', as shown in the above example, or you can 'cat' a saved output buffer to it.
/* File: nvme_parse_id_ns.c */ #include <linux/nvme.h> #include <stdio.h> #include <unistd.h> int main(int argc, char **argv) { unsigned char buf[sizeof(struct nvme_id_ns)]; struct nvme_id_ns *ns = (struct nvme_id_ns *)buf; if (read(STDIN_FILENO, buf, sizeof(buf))) return 1; printf("nsze : %#llx\n", ns->nsze); printf("ncap : %#llx\n", ns->ncap); return 0; }
NVME
Part of the nvme-user suite