Documentation/filesystems/autofs.rst

21    in that data base at the time of access will be used to provide
32 and mounts filesystems.  This will often be the "automount" program,
93 "`stat`" will (normally) cause the `d_op->d_automount()` dentry operation
102 everything is ready.  It will then return "`NULL`" indicating that the
121 directory, d_manage() will be called with the `rcu_walk` parameter set
168 will be set.
175 RCU-walk will never call `->d_automount`; the filesystems must already
189 mounted, it *will* fall back to REF-walk.  `d_manage()` cannot make the
197 autofs will return `-ECHILD` if an expiry of the filesystem has been
214 the `umount` system call.  Unmounting with MNT_EXPIRE will fail unless
224 or removal is successful the filesystem will be returned to the state
226 will trigger normal auto-mount processing.  In particular, `rmdir` and
233 processes will see an empty directory as soon as the filesystem is
281 mounts.  If it finds something in the root directory to expire it will
289 the **AUTOFS_IOC_EXPIRE_MULTI** ioctl.  This will work for both direct and
290 indirect mounts.  If it selects an object to expire, it will notify
292 will block until the daemon acknowledges the expiry notification.
297 `d_manage` will block until the daemon affirms that the unmount has
315 provided through an ioctl as will be described below.
321 be passed using the 'fd=' mount option.  autofs will write
355 The pipe will be set to "packet mode" (equivalent to passing
356 `O_DIRECT`) to _pipe2(2)_ so that a read from the pipe will return at
357 most one packet, and any unread portion of a packet will be discarded.
369 The root directory of an autofs filesystem will respond to a number of
430 	**AUTOFS_EXP_LEAVES** will select a leaf rather than a top-level
504 	On successful return, `requester.uid` and `requester.gid` will be
536 Once in catatonic mode attempts to access non-existing names will
537 result in `ENOENT` while attempts to access existing directories will
539 traps will not fire.
577 locations will not behave as expected.  In particular access to those
578 other locations will likely result in the `ELOOP` error ::