[PATCH v3 03/13] docs: path-lookup: update path_mountpoint() part
From: Fox Chen <hidden>
Date: 2021-05-27 09:17:16
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Subsystem:
documentation, the rest · Maintainers:
Jonathan Corbet, Linus Torvalds
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 <redacted>
---
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 6ea0880fb982..652d3284f178 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 +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
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2.31.1