STRUCT V9FS_SESSION_INFO(9)

🩷 struct v9fs_session_info(9) — per-instance session information 🩷

okay so this is from the Kernel API Manual, bestie, and it’s the struct v9fs_session_info page — yes, we’re doing kernel struct lore today 💖

🌸 NAME 🌸

struct v9fs_session_info — per-instance session information. that’s the whole name vibe, no cap ✨

💖 SYNOPSIS 💖

here’s the struct exactly as it appears, no edits, no skipping, iykyk:

       struct v9fs_session_info {
           unsigned int flags;
           unsigned char nodev;
           unsigned short debug;
           unsigned int afid;
           unsigned int cache;
           unsigned int ndentry_timeout_ms;
         #ifdef CONFIG_9P_FSCACHE;
           char *cachetag;
           struct fscache_volume *fscache;
         #endif;
           char *uname;
           char *aname;
           unsigned int maxdata;
           kuid_t dfltuid;
           kgid_t dfltgid;
           kuid_t uid;
           struct p9_client *clnt;
           struct list_head slist;
           struct rw_semaphore rename_sem;
           long session_lock_timeout;
           struct rcu_head rcu;
        };

🦋 Members 🦋

member-by-member tea, bestie — these are the one-liners the page gives us 🎀

• flags — session options of type p9_session_flags.
• nodev — set to 1 to disable device mapping.
• debug — debug level.
• afid — authentication handle.
• cache — cache mode of type p9_cache_bits.
• ndentry_timeout_ms — Negative dentry caching retention time.
• cachetag — the tag of the cache associated with this session. this one lives inside the CONFIG_9P_FSCACHE block, periodt 💅
• fscache — session cookie associated with FS-Cache.
• uname — string user name to mount hierarchy as.
• aname — mount specifier for remote hierarchy.
• maxdata — maximum data to be sent/recvd per protocol message.
• dfltuid — default numeric userid to mount hierarchy as.
• dfltgid — default numeric groupid to mount hierarchy as.
• uid — if V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy.
• clnt — reference to 9P network client instantiated for this session.
• slist — reference to list of registered 9p sessions.

and yeah, rename_sem, session_lock_timeout, and rcu are in the struct too — the original member rundown doesn’t give them their own one-liners, so I’m not out here inventing tea 🙈

💜 Description 💜

This structure holds state for each session instance established during a sys_mount.

Bugs: there seems to be a lot of state which could be condensed and/or removed.

like… the struct said “I contain multitudes” and the page said “maybe too many multitudes” 😭

🔥 SEE ALSO 🔥

• Kernel file ./fs/9p/v9fs.h
• enum p9_cache_shortcuts(9)
• enum p9_cache_bits(9)
• v9fs_get_inode_from_fid(9)
• v9fs_get_new_inode_from_fid(9)

okay bestie, that’s the page 💅 — source/version is ./fs/9p, date is October 2026, and this sign-off is officially iconic 👑✨