3  *  linux/fs/locks.c
5  * We implement four types of file locks: BSD locks, posix locks, open
6  * file description locks, and leases.  For details about BSD locks,
17  * Waiting and applied locks are all kept in trees whose properties are:
126  * The global file_lock_list is only used for displaying /proc/locks, so we
145  * We hash locks by lockowner in order to optimize searching for the lock a
149  * buckets when we have more lockowners holding locks, but that's a little
161  * requests (in contrast to those that are acting as records of acquired locks).
223 		pr_warn("Leaked locks on dev=0x%x:0x%x ino=0x%lx:\n",  in locks_check_ctx_lists()
586 /* Check if two locks overlap each other.
595  * Check whether two locks have the same owner.
717 	 * no new locks can be inserted into its fl_blocked_requests list, and  in locks_delete_block()
840  * checks for shared/exclusive status of overlapping locks.
858 	/* POSIX locks owned by the same process do not conflict with  in posix_locks_conflict()
877 	/* F_UNLCK checks any locks on the same fd. */  in posix_test_locks_conflict()
892 	/* FLOCK locks referring to the same filp do not conflict with  in flock_locks_conflict()
945  * locks.
964  * For FL_OFDLCK locks, the owner is the filp, not the files_struct.
970  * locks that just checks for the case where two tasks are attempting to
971  * upgrade from read to write locks on the same inode.
1001 	 * FL_OFDLCK locks, since they aren't owned by a process, per-se.  in posix_locks_deadlock()
1015 /* Try to create a FLOCK lock on filp. We always insert new FLOCK locks
1016  * after any leases, but before any posix locks.
1117 	 * In some cases we can be sure, that no new locks will be needed  in posix_lock_inode()
1130 	 * New lock request. Walk all POSIX locks and look for conflicts. If  in posix_lock_inode()
1156 			 * locks list must be done while holding the same lock!  in posix_lock_inode()
1161 			 * Ensure that we don't find any locks blocked on this  in posix_lock_inode()
1186 	/* Process locks with this owner. */  in posix_lock_inode()
1208 			 * locks to the higher end address.  in posix_lock_inode()
1273 	 * The above code only modifies existing locks in case of merging or  in posix_lock_inode()
1321 	 * Free any unused locks.  in posix_lock_inode()
1339  * We merge adjacent & overlapping locks whenever possible.
1340  * POSIX locks are sorted by owner task, then by starting address
2076 	 * LOCK_MAND locks were broken for a long time in that they never  in SYSCALL_DEFINE2()
2265  * locks, the ->lock() interface may return asynchronously, before the lock has
2277  * grants a lock so the VFS can find out which locks are locally held and do
2355 	 * If the cmd is requesting file-private locks, then set the  in fcntl_setlk()
2384 	 * Detect close/fcntl races and recover by zapping all POSIX locks  in fcntl_setlk()
2387 	 * unlocking though, or for OFD locks.  in fcntl_setlk()
2477 	 * If the cmd is requesting file-private locks, then set the  in fcntl_setlk64()
2506 	 * Detect close/fcntl races and recover by zapping all POSIX locks  in fcntl_setlk64()
2509 	 * unlocking though, or for OFD locks.  in fcntl_setlk64()
2535  * from the task's fd array.  POSIX locks belonging to this task
2546 	 * If there are no locks held on this file, we don't need to call  in locks_remove_posix()
2627 	/* remove any OFD locks */  in locks_remove_file()
2630 	/* remove flock locks */  in locks_remove_file()
2660  * vfs_inode_has_locks - are any file locks held on @inode?
2661  * @inode: inode to check for locks
2663  * Return true if there are any FL_POSIX or FL_FLOCK locks currently
2898 	proc_create_seq_private("locks", 0, NULL, &locks_seq_operations,  in proc_locks_init()