SYNOPSIS

nvme [<global-options>] show-regs <device>

DESCRIPTION

Reads and shows the controller registers. For an NVMe over PCIe controller, nvme maps its PCI memory space through sysfs (the resource0 file of the PCI device) and reads them there. For an NVMe over Fabrics controller, it reads its properties with Property Get commands: CAP, VS, CC, CSTS and the ones of NSSR, NSSD and CRTO the controller implements.

The <device> parameter is mandatory and must be the nvme admin character device (ex: /dev/nvme0).

With -v, the fields of each register are shown decoded. The JSON output has the value of each register under its name, with -v an object of the value and its decoded fields. The binary output is the registers from 0h to E1Bh, as they are in the PCI memory space, with zeros for the ones not read.

OPTIONS

GLOBAL OPTIONS

The following options are defined at the top-level nvme command and are available to this subcommand:

--dry-run

Print the command that would be executed, but do not actually execute it.

--no-ioctl-probing

Disable probing for 64-bit IOCTL support.

--no-retries

Disable retry logic on transient errors.

-o <fmt>
--output-format=<fmt>

Set the reporting format to normal, tabular, 'json, or binary. Only one output format may be used at a time.

--output-format-version=<version>

Select the output format version. Version 1 uses the original field naming, while version 2 (default) provides more consistent and script-friendly field names. Other versions are rejected.

--quiet

Suppress informational messages. Errors are still reported, and --quiet cancels any --verbose for the library log level.

--set-options=<key=value>[,<key=value>…]

Set libnvme library options for this invocation. Supported keys are force-4k, mi-probe-enabled, test-base-dir and test-sysfs-dir.

--timeout=<ms>

Set the timeout for the command in milliseconds. infinite or -1 waits without a time limit (0xffffffff).

-v
--verbose

Increase the level of detail in the output. May be specified multiple times to further increase verbosity.

These options can also be set as machine-wide defaults in nvme-cli.conf(5). A command-line flag always overrides the file.

EXAMPLES

  • Show the NVMe over PCIe controller registers or the NVMe over Fabric controller properties in a binary format: 

    # nvme show-regs /dev/nvme0 -o binary

  • Show the NVMe over PCIe controller registers or the NVMe over Fabric controller properties in a human readable format: 

    # nvme show-regs /dev/nvme0 -v

  • Show the NVMe over PCIe controller registers or NVMe-oF controller properties in a json format: 

    # nvme show-regs /dev/nvme0 -o json

NVME

Part of the nvme-user suite