__fcntl_getlease(9)

💅 __fcntl_getlease — the lease-check queen 💅

okay so bestie, welcome to the Kernel API Manual entry for __fcntl_getlease — the function whose whole main-character job is to enquire what lease is currently active. ngl, it's giving “who's holding the lease rn?” energy, and we're obsessed. ✨

🌸 NAME 🌸

__fcntl_getlease — Enquire what lease is currently active. periodt. 💅

🦋 SYNOPSIS 🦋

Here's the signature, bestie — exact vibes only:

int __fcntl_getlease (struct file *filp , unsigned int flavor );

💖 ARGUMENTS 💖

Two arguments, no cap:

• filp — the file 🗂️
• flavor — type of lease flags to check 🔍

🎀 DESCRIPTION 🎀

okay so here's the tea: the value returned by this function will be one of these (if no lease break is pending):

• F_RDLCK — to indicate a shared lease is held. 💞
• F_WRLCK — to indicate an exclusive lease is held. 👑
• F_UNLCK — to indicate no lease is held. 🚫

and if a lease break is pending, it's one of these:

• F_RDLCK — to indicate an exclusive lease needs to be changed to a shared lease (or removed). 🔁
• F_UNLCK — to indicate the lease needs to be removed. 🧹

XXX: sfr & willy disagree over whether F_INPROGRESS should be returned to userspace. 💀

🔥 SEE ALSO 🔥

Kernel file ./fs/locks.c is where the lock lore lives, and the whole lock-adjacent friend group is:

• locks_owner_has_blockers(9)
• lease_open_conflict(9)
• locks_delete_block(9)
• posix_lock_file(9)
• posix_lock_inode_wait(9)
• inode_lease_ignore_mask(9)
• __break_lease(9)
• lease_get_mtime(9)
• generic_setlease(9)
• vfs_setlease(9)
• fcntl_setlease(9)
• fcntl_setdeleg(9)
• flock_lock_inode_wait(9)
• locks_lock_inode_wait(9)
• sys_flock(9)
• vfs_test_lock(9)
• locks_translate_pid(9)
• vfs_lock_file(9)
• vfs_cancel_lock(9)
• vfs_inode_has_locks(9)

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source/version: ./fs · date: October 2026 — mwah, bye bestie 💋🫶