libnvme(9)

💖 libnvme(9) — enum nbft_ssns_flags 💖

okay so bestie, welcome to the libnvme API manual, and today's main character is enum nbft_ssns_flags — literally the Subsystem and Namespace Specific Flags Field (Figure 18) 🎀. yes the figure number is part of the vibe. no cap. let's get into it ✨

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🌸 NAME 🌸

enum nbft_ssns_flags — Subsystem and Namespace Specific Flags Field (Figure 18). that's it, that's the whole name, and it ate 💅

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🦋 SYNOPSIS 🦋

enum nbft_ssns_flags {
    NBFT_SSNS_VALID ,
    NBFT_SSNS_NON_BOOTABLE_ENTRY ,
    NBFT_SSNS_USE_SECURITY_FIELD ,
    NBFT_SSNS_DHCP_ROOT_PATH_OVERRIDE ,
    NBFT_SSNS_EXTENDED_INFO_IN_USE ,
    NBFT_SSNS_SEPARATE_DISCOVERY_CTRL ,
    NBFT_SSNS_DISCOVERED_NAMESPACE ,
    NBFT_SSNS_UNAVAIL_NAMESPACE_MASK ,
    NBFT_SSNS_UNAVAIL_NAMESPACE_NOTIND ,
    NBFT_SSNS_UNAVAIL_NAMESPACE_AVAIL ,
    NBFT_SSNS_UNAVAIL_NAMESPACE_UNAVAIL

};

yes, there's a lil blank line before the closing brace, and yes we're keeping it exactly as it is, because accuracy is the whole personality here 🫶

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⭐ Constants ⭐

okay so this is where the actual lore lives. every flag is either set to 1h or cleared to 0h, and bestie, the difference is everything. 👑

• NBFT_SSNS_VALID — Descriptor Valid: if it's set to 1h, this descriptor is valid. if it's cleared to 0h, it's not valid. and lowkey this is so real of them: a host that supports NVMe-oF Boot but doesn't currently have a remote Subsystem and Namespace assigned is allowed to clear this bit to 0h. no assignment, no validity, periodt. 🌈
• NBFT_SSNS_NON_BOOTABLE_ENTRY — Non-bootable Entry Flag:</char>? no wait — Non-bootable Entry Flag: if set to 1h, this flag is telling you that this SSNS Descriptor contains a namespace that's admin-purposeful to the boot process, but the pre-OS may not have established connectivity to it or evaluated its contents. such namespaces may hold supplemental data the Administrator deemed relevant for the pre-OS → OS handoff. this can include properties like a UEFI device path that may not have been created for this namespace. which means an OS runtime may still need the contents of such a namespace to finish later stages of boot 😭. if cleared to 0h, then this namespace had no special administrative intent at all. simple as that 💫
• NBFT_SSNS_USE_SECURITY_FIELD — Use Security Flag: set to 1h → there is a Security Profile Descriptor associated with this SSNS record, and the Security Profile Descriptor Index field is valid 🔥. cleared to 0h → no Security Profile Descriptor for this SSNS record, and the Security Profile Descriptor Index field is not valid. it's giving "the index is a lie" energy 💀
• NBFT_SSNS_DHCP_ROOT_PATH_OVERRIDE — DHCP Root-Path Override Flag: set to 1h → this SSNS descriptor was populated by consuming the DHCP Root-Path on this interface. cleared to 0h → the DHCP Root-Path was not used in populating the SSNS descriptor. iykyk 🌸
• NBFT_SSNS_EXTENDED_INFO_IN_USE — SSNS Extended Info In-use Flag: set to 1h → the SSNS Extended Information Offset field and the SSNS Extended Information Length field are both valid. and this flag, when it's 1h, means a Subsystem and Namespace Extended Information Descriptor corresponding to this descriptor is present. both fields, present and accounted for, slay ✨
• NBFT_SSNS_SEPARATE_DISCOVERY_CTRL — Separate Discovery Controller Flag: set to 1h → the Discovery controller associated with this volume lives on a different transport address than the one specified in the Subsystem Transport Address Heap Object Reference. cleared to 0h → the Discovery controller is the same as the Subsystem Transport Address Heap Object Reference. same address, no drama 🎀
• NBFT_SSNS_DISCOVERED_NAMESPACE — Discovered Namespace Flag: set to 1h → this namespace was acquired through discovery 🦋. cleared to 0h → this namespace was explicitly configured in the system. found vs. hand-placed, we love a distinction 💜
• NBFT_SSNS_UNAVAIL_NAMESPACE_MASK — Mask to get Unavailable Namespace Flag: this field tells you the availability of the namespace at a specific point in time. and here's the caveat bestie, listen up: such use is only a hint, and using it does not guarantee that the referenced namespace will be available at any future point in time. time is a construct, namespace availability even more so 😭
• NBFT_SSNS_UNAVAIL_NAMESPACE_NOTIND — Not Indicated by Driver: no information is provided. that's the whole thing. the void. the silence. iconic 🙈
• NBFT_SSNS_UNAVAIL_NAMESPACE_AVAIL — Available: a referenced namespace described by this flag was previously accessible by the pre-OS driver ✅
• NBFT_SSNS_UNAVAIL_NAMESPACE_UNAVAIL — Unavailable: this namespace was administratively configured but unattempted, unavailable or inaccessible when establishing connectivity by the pre-OS driver 💀. it was supposed to be there. it was not. we've all been there.

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💡 friendly reminder bestie: those 1h / 0h values are hex, and every single one of these flags keeps its exact meaning up there. don't go inventing new behaviour, the spec said what it said 🫶

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and that's the whole page!! mwah 💋 this manual page was served up by the libnvme API Manual, October 2026 edition — enum nbft_ssns_flags, pages libnvme(9), source/version and date all present and accounted for, no cap 🌟 bye bestie, go read your flags responsibly 🧚‍♀️💖