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From:   Fox Chen <foxhlchen@gmail.com>
To:     neilb@suse.de
Cc:     Fox Chen <foxhlchen@gmail.com>, corbet@lwn.net,
        vegard.nossum@oracle.com, viro@zeniv.linux.org.uk,
        rdunlap@infradead.org, grandmaster@al2klimov.de,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        gregkh@linuxfoundation.org
Subject: [PATCH v2 03/12] docs: path-lookup: update path_mountpoint() part
Date:   Tue, 16 Mar 2021 13:47:18 +0800
Message-Id: <20210316054727.25655-4-foxhlchen@gmail.com>
In-Reply-To: <20210316054727.25655-1-foxhlchen@gmail.com>
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path_mountpoint() doesn't exist anymore. Have been folded
into path_lookup_at when flag is set with LOOKUP_MOUNTPOINT.
Check commit: commit 161aff1d93abf0e ("LOOKUP_MOUNTPOINT: fold
path_mountpointat() into path_lookupat()")

Signed-off-by: Fox Chen <foxhlchen@gmail.com>
---
 Documentation/filesystems/path-lookup.rst | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/Documentation/filesystems/path-lookup.rst b/Documentation/filesystems/path-lookup.rst
index a29d714431a3..b6a301b78121 100644
--- a/Documentation/filesystems/path-lookup.rst
+++ b/Documentation/filesystems/path-lookup.rst
@@ -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 further
+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
-- 
2.30.2