docs: path-lookup: update path_mountpoint() part

path_mountpoint() doesn't exist anymore. Have been folded
into path_lookup_at when flag is set with LOOKUP_MOUNTPOINT.
Check commit: commit 161aff1d93 ("LOOKUP_MOUNTPOINT: fold
path_mountpointat() into path_lookupat()")

Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-4-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
Fox Chen 2021-05-27 17:16:08 +08:00 committed by Jonathan Corbet
parent 084c86837a
commit 8593d2cc8c

View file

@ -472,7 +472,7 @@ Handling the final component
``nd->last_type`` to refer to the final component of the path. It does
not call ``walk_component()`` that last time. Handling that final
component remains for the caller to sort out. Those callers are
``path_lookupat()``, ``path_parentat()``, ``path_mountpoint()`` and
``path_lookupat()``, ``path_parentat()`` and
``path_openat()`` each of which handles the differing requirements of
different system calls.
@ -488,12 +488,10 @@ perform their operation.
object is wanted such as by ``stat()`` or ``chmod()``. It essentially just
calls ``walk_component()`` on the final component through a call to
``lookup_last()``. ``path_lookupat()`` returns just the final dentry.
``path_mountpoint()`` handles the special case of unmounting which must
not try to revalidate the mounted filesystem. It effectively
contains, through a call to ``mountpoint_last()``, an alternate
implementation of ``lookup_slow()`` which skips that step. This is
important when unmounting a filesystem that is inaccessible, such as
It is worth noting that when flag ``LOOKUP_MOUNTPOINT`` is set,
``path_lookupat()`` will unset LOOKUP_JUMPED in nameidata so that in the
subsequent path traversal ``d_weak_revalidate()`` won't be called.
This is important when unmounting a filesystem that is inaccessible, such as
one provided by a dead NFS server.
Finally ``path_openat()`` is used for the ``open()`` system call; it