From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 30 May 2025 22:38:29 +0000 (-0700)
Subject: Merge tag 'pull-automount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
X-Git-Tag: v6.16-rc1~104
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=0f70f5b08a47a3bc1a252e5f451a137cde7c98ce;p=linux-block.git

Merge tag 'pull-automount' of git://git./linux/kernel/git/viro/vfs

Pull automount updates from Al Viro:
 "Automount wart removal

  A bunch of odd boilerplate gone from instances - the reason for
  those was the need to protect the yet-to-be-attched mount from
  mark_mounts_for_expiry() deciding to take it out.

  But that's easy to detect and take care of in mark_mounts_for_expiry()
  itself; no need to have every instance simulate mount being busy by
  grabbing an extra reference to it, with finish_automount() undoing
  that once it attaches that mount.

  Should've done it that way from the very beginning... This is a
  flagday change, thankfully there are very few instances.

  vfs_submount() is gone - its sole remaining user (trace_automount)
  had been switched to saner primitives"

* tag 'pull-automount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  kill vfs_submount()
  saner calling conventions for ->d_automount()
---

0f70f5b08a47a3bc1a252e5f451a137cde7c98ce
diff --cc Documentation/filesystems/porting.rst
index 3111ef5592f3,749637231773..3616d7161dab
--- a/Documentation/filesystems/porting.rst
+++ b/Documentation/filesystems/porting.rst
@@@ -1206,40 -1206,7 +1206,46 @@@ will fail-safe
  
  ---
  
 +** mandatory**
 +
 +lookup_one(), lookup_one_unlocked(), lookup_one_positive_unlocked() now
 +take a qstr instead of a name and len.  These, not the "one_len"
 +versions, should be used whenever accessing a filesystem from outside
 +that filesysmtem, through a mount point - which will have a mnt_idmap.
 +
 +---
 +
 +** mandatory**
 +
 +Functions try_lookup_one_len(), lookup_one_len(),
 +lookup_one_len_unlocked() and lookup_positive_unlocked() have been
 +renamed to try_lookup_noperm(), lookup_noperm(),
 +lookup_noperm_unlocked(), lookup_noperm_positive_unlocked().  They now
 +take a qstr instead of separate name and length.  QSTR() can be used
 +when strlen() is needed for the length.
 +
 +For try_lookup_noperm() a reference to the qstr is passed in case the
 +hash might subsequently be needed.
 +
 +These function no longer do any permission checking - they previously
 +checked that the caller has 'X' permission on the parent.  They must
 +ONLY be used internally by a filesystem on itself when it knows that
 +permissions are irrelevant or in a context where permission checks have
 +already been performed such as after vfs_path_parent_lookup()
 +
 +---
 +
 +** mandatory**
 +
 +d_hash_and_lookup() is no longer exported or available outside the VFS.
 +Use try_lookup_noperm() instead.  This adds name validation and takes
 +arguments in the opposite order but is otherwise identical.
 +
 +Using try_lookup_noperm() will require linux/namei.h to be included.
 +
++---
++
+ **mandatory**
+ 
+ Calling conventions for ->d_automount() have changed; we should *not* grab
+ an extra reference to new mount - it should be returned with refcount 1.