LBLK-WRITE-READ-PI(1)

✨ LBLK-WRITE-READ-PI ✨

okay so bestie, welcome to lblk-write-read-pi — it lives in the xNVMe manual (section 1, we're fancy like that 💅). It writes stuff, then reads it back, and it does the whole thing with protection information. yes, PI. we love a data-integrity moment. 🛡️✨

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🌸 NAME 🌸

lblk-write-read-pi — Writes and then read with protection information

no cap, that's literally the whole job description. 💖

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🦋 SYNOPSIS 🦋

lblk write-read-pi <uri> [<args>]

that's the shape of it. <uri> is the required main-character, everything in [<args>] is optional supporting cast. 🌈

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🎀 DESCRIPTION 🎀

Writes and then read with protection information

it's giving "write it, read it back, check the PI the whole time." iconic behavior fr fr. 🫶

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💖 REQUIRED 💖

these ones? mandatory. you cannot skip them, the command will simply not be having it. 😭

• <uri> — Device URI, e.g. /dev/nvme0n1, 0000:01:00.1, 10.9.8.1.8888, \.PhysicalDrive1

like, this is the where. which device are we talking to. periodt.

• --slba 0xNUM — Start Logical Block Address

your starting point, in hex, 0x and everything. the beginning of the saga. ⭐

• --nlb NUM — Number of LBAs (NOTE: zero-based value)

how many logical blocks we're doing. and heads up bestie: this is a zero-based value, so the math is not mathing the way your instincts think it is. 🙈

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✨ OPTIONAL ✨

the vibes-extras. fully optional, but they let you customize the whole situation. pick and choose, it's your world. 💅

• [ --nsid 0xNUM ] — Namespace Identifier for Command Construction

which namespace we're building the command for. 🎯

• [ --pract NUM ] — Protection Information Action

the PI action. yes, action. it does a thing. 🎬

• [ --prchk 0xNUM ] — Protection Information Check

the PI check. we verifying. we're thorough like that. ✅

• [ --apptag 0xNUM ] — Application Tag

a little tag, for your application. cute. 🏷️

• [ --apptag_mask 0xNUM ] — Application Tag Mask

the mask that goes with the tag. they're a duo. 💞

• [ --data-input FILE ] — Path to data input-file

where the actual data is coming from. 🍓

• [ --meta-input FILE ] — Path to meta input-file

and here's where the meta lives. ✨

• [ --subnqn STRING ] — Subsystem NQN of the NVMe over Fabrics endpoint e.g. 'nqn.2022-06.io.xnvme:ctrlnode1'

for when you're doing NVMe over Fabrics and need to name your subsystem. very demure, very networked. 🌐

• [ --hostnqn STRING ] — The host NQN to use when connecting to NVMe over Fabrics controllers

your host's NQN, for the Fabrics connection. the other half of the NQN love story. 🫶

• [ --be STRING ] — xNVMe backend, e.g. 'linux', 'spdk', 'fbsd', 'macos', 'posix', 'windows'

which backend you're riding with. choose your fighter. 🔥

• [ --dev-nsid 0xNUM ] — Namespace Identifier for Device Handle

plot twist: this is the namespace ID for the device handle, not the command. yes, they're different options. yes, it matters. iykyk. 👑

• [ --admin STRING ] — xNVMe admin. command-interface, e.g. 'nvme', 'block'

which admin command-interface to use. 🛠️

• [ --mem STRING ] — xNVMe buffer/memory manager

picks your buffer/memory manager. memory management is self-care. 🧚

• [ --direct NUM ] — Bypass layers

bypass layers. skip the middlemen. main character energy, going straight to the metal. 💀

• [ --sync STRING ] — xNVMe sync. command-interface, e.g. 'nvme', 'block'

the sync command-interface. same energy as --admin, different lane. 🌈

• [ --help ] — Show usage / help

when in doubt, ask for help. no shame in it, bestie. 🎀

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👀 SEE ALSO 👀

Full documentation at: <https://xnvme.io/>

go read it, it's good for you. 📚💜

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💜 AUTHOR 💜

Written by Simon A. F. Lund <simon.lund@samsung.com> on behalf of Samsung

shoutout to Simon, absolute legend for writing this down so we didn't have to. 🙌

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and that's the whole page bestie!! this was xNVMe, version dated 09 September 2024, page LBLK-WRITE-READ-PI(1) — go write, go read, go check that protection information. slay. 💅✨🦋