Patch "libfs: Add simple_offset_rename() API" has been added to the 6.6-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    libfs: Add simple_offset_rename() API

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     libfs-add-simple_offset_rename-api.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


From stable+bounces-110405-greg=kroah.com@vger.kernel.org Fri Jan 24 20:21:49 2025
From: cel@kernel.org
Date: Fri, 24 Jan 2025 14:19:40 -0500
Subject: libfs: Add simple_offset_rename() API
To: Hugh Dickins <hughd@google.com>, Andrew Morten <akpm@linux-foundation.org>, Christian Brauner <brauner@kernel.org>, Al Viro <viro@zeniv.linux.org.uk>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Sasha Levin <sashal@kernel.org>
Cc: <linux-fsdevel@vger.kernel.org>, <stable@vger.kernel.org>, <linux-mm@kvack.org>, yukuai3@huawei.com, yangerkun@huawei.com, Chuck Lever <chuck.lever@oracle.com>
Message-ID: <20250124191946.22308-6-cel@kernel.org>

From: Chuck Lever <chuck.lever@oracle.com>

[ Upstream commit 5a1a25be995e1014abd01600479915683e356f5c ]

I'm about to fix a tmpfs rename bug that requires the use of
internal simple_offset helpers that are not available in mm/shmem.c

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://lore.kernel.org/r/20240415152057.4605-3-cel@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/libfs.c         |   21 +++++++++++++++++++++
 include/linux/fs.h |    2 ++
 mm/shmem.c         |    3 +--
 3 files changed, 24 insertions(+), 2 deletions(-)

--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -357,6 +357,27 @@ int simple_offset_empty(struct dentry *d
 }
 
 /**
+ * simple_offset_rename - handle directory offsets for rename
+ * @old_dir: parent directory of source entry
+ * @old_dentry: dentry of source entry
+ * @new_dir: parent_directory of destination entry
+ * @new_dentry: dentry of destination
+ *
+ * Caller provides appropriate serialization.
+ *
+ * Returns zero on success, a negative errno value on failure.
+ */
+int simple_offset_rename(struct inode *old_dir, struct dentry *old_dentry,
+			 struct inode *new_dir, struct dentry *new_dentry)
+{
+	struct offset_ctx *old_ctx = old_dir->i_op->get_offset_ctx(old_dir);
+	struct offset_ctx *new_ctx = new_dir->i_op->get_offset_ctx(new_dir);
+
+	simple_offset_remove(old_ctx, old_dentry);
+	return simple_offset_add(new_ctx, old_dentry);
+}
+
+/**
  * simple_offset_rename_exchange - exchange rename with directory offsets
  * @old_dir: parent of dentry being moved
  * @old_dentry: dentry being moved
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3198,6 +3198,8 @@ void simple_offset_init(struct offset_ct
 int simple_offset_add(struct offset_ctx *octx, struct dentry *dentry);
 void simple_offset_remove(struct offset_ctx *octx, struct dentry *dentry);
 int simple_offset_empty(struct dentry *dentry);
+int simple_offset_rename(struct inode *old_dir, struct dentry *old_dentry,
+			 struct inode *new_dir, struct dentry *new_dentry);
 int simple_offset_rename_exchange(struct inode *old_dir,
 				  struct dentry *old_dentry,
 				  struct inode *new_dir,
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -3434,8 +3434,7 @@ static int shmem_rename2(struct mnt_idma
 			return error;
 	}
 
-	simple_offset_remove(shmem_get_offset_ctx(old_dir), old_dentry);
-	error = simple_offset_add(shmem_get_offset_ctx(new_dir), old_dentry);
+	error = simple_offset_rename(old_dir, old_dentry, new_dir, new_dentry);
 	if (error)
 		return error;
 


Patches currently in stable-queue which might be from cel@kernel.org are

queue-6.6/libfs-replace-simple_offset-end-of-directory-detection.patch
queue-6.6/libfs-re-arrange-locking-in-offset_iterate_dir.patch
queue-6.6/libfs-add-simple_offset_empty.patch
queue-6.6/shmem-fix-shmem_rename2.patch
queue-6.6/revert-libfs-add-simple_offset_empty.patch
queue-6.6/libfs-use-d_children-list-to-iterate-simple_offset-directories.patch
queue-6.6/libfs-define-a-minimum-directory-offset.patch
queue-6.6/libfs-return-enospc-when-the-directory-offset-range-is-exhausted.patch
queue-6.6/libfs-fix-simple_offset_rename_exchange.patch
queue-6.6/libfs-add-simple_offset_rename-api.patch