Documentation/filesystems/autofs.rst

23    filesystem can even be programmatic rather than database-backed,
30 The "autofs" filesystem module is only one part of an autofs system.
39 filesystem type.  Several "autofs" filesystems can be mounted and they
45 An autofs filesystem can contain 3 sorts of objects: directories,
62 directory is a mount trap only if the filesystem is mounted *direct*
66 filesystem is mounted *indirect* and they are empty.
85 filesystem can be designated as a trap.  This involves two separate
94 to be called. The task of this method is to find the filesystem that
96 responsible for actually mounting the root of this filesystem on the
99 autofs doesn't find the filesystem itself but sends a message to the
100 automount daemon asking it to find and mount the filesystem.  The
110 automount daemon would not be able to mount a filesystem on the 'trap'
120 Firstly, before checking to see if any filesystem is mounted on the
129    expiry (automatic unmounting of the mounted filesystem) to
144    filesystem can be mounted below the first and for both of them to
195 mounted filesystem, otherwise it should return 0.
197 autofs will return `-ECHILD` if an expiry of the filesystem has been
207 mounts that were created by `d_automount()` returning a filesystem to be
208 mounted.  As autofs doesn't return such a filesystem but leaves the
215 a previous attempt had been made, and the filesystem has been inactive
222 unmount any filesystems mounted on the autofs filesystem or remove any
224 or removal is successful the filesystem will be returned to the state
228 filesystem would, so an attempt to access a recently-removed object is
233 processes will see an empty directory as soon as the filesystem is
271 compares it with the "timeout" value set when the filesystem was
305 and the filesystem.  As we have already seen, the daemon can create and
306 remove directories and symlinks using normal filesystem operations.
310 When an autofs filesystem is mounted the pgid of the mounting
320 When an autofs filesystem is mounted, the 'write' end of a pipe must
369 The root directory of an autofs filesystem will respond to a number of
397 	the filesystem could be unmounted.  This is only a hint as
436 It is not always possible to open the root of an autofs filesystem,
437 particularly a *direct* mounted filesystem.  If the automount daemon
441 which can be used to communicate directly with the autofs filesystem.
474 filesystem is identified by the `path`.  All other commands identify
475 the filesystem by the `ioctlfd` which is a file descriptor open on the
489 	on the root of an autofs filesystem.  The filesystem is identified
496 	if the filesystem is in
503 	name within the filesystem that has been auto-mounted on.
541 When the filesystem is mounted a _uid_ and _gid_ can be given which
543 filesystem is in catatonic mode, any process with a matching UID can
569 filesystem to appear at multiple places in one or more filesystem
570 name spaces.  For this to work sensibly, the autofs filesystem should
576 an autofs filesystem and if mounts on that are not 'shared', other