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nvme-id-ctrl(1)


NAME

   nvme-id-ctrl - Send NVMe Identify Controller, return result and
   structure

SYNOPSIS

   nvme id-ctrl <device> [-v | --vendor-specific] [-b | --raw-binary]
                           [-o <fmt> | --output-format=<fmt>]

DESCRIPTION

   For the NVMe device given, sends an identify controller 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).

   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

   -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.

   -o <format>, --output-format=<format>
       Set the reporting format to normal, json, or binary. Only one
       output format can be used at a time.

EXAMPLES

   *   Has the program interpret the returned buffer and display the known
       fields in a human readable format:

           # nvme id-ctrl /dev/nvme0

   *   In addition to showing the known fields, has the program to display
       the vendor unique field:

           # nvme id-ctrl /dev/nvme0 --vendor-specific
           # nvme id-ctrl /dev/nvme0 -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-ctrl /dev/nvme0 --raw-binary > id_ctrl.raw
           # nvme id-ctrl /dev/nvme0 -b > id_ctrl.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-ctrl /dev/nvme0 --raw-binary | nvme_parse_id_ctrl

       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_ctrl.c */

       #include <linux/nvme.h>
       #include <stdio.h>
       #include <unistd.h>

       int main(int argc, char **argv)
       {
               unsigned char buf[sizeof(struct nvme_id_ctrl)];
               struct nvme_id_ctrl *ctrl = (struct nvme_id_ctrl *)buf;

               if (read(STDIN_FILENO, buf, sizeof(buf)))
                       return 1;

               printf("vid   : %#x\n", ctrl->vid);
               printf("ssvid : %#x\n", ctrl->ssvid);
               return 0;
       }

NVME

   Part of the nvme-user suite



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