6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever <chuck.lever@xxxxxxxxxx> [ 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@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240415152057.4605-3-cel@xxxxxxxxxx Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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;
