On Mon, Feb 24, 2025 at 09:20:37PM +0000, Al Viro wrote:
> ... and store it in ->s_d_flags, to be used in __d_alloc()
>
> Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> ---
Reviewed-by: Christian Brauner <brauner@xxxxxxxxxx>
> fs/dcache.c | 6 ++++--
> include/linux/fs.h | 1 +
> 2 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/fs/dcache.c b/fs/dcache.c
> index 1201149e1e2c..a4795617c3db 100644
> --- a/fs/dcache.c
> +++ b/fs/dcache.c
> @@ -1705,14 +1705,14 @@ static struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name)
> dentry->d_inode = NULL;
> dentry->d_parent = dentry;
> dentry->d_sb = sb;
> - dentry->d_op = NULL;
> + dentry->d_op = sb->__s_d_op;
> + dentry->d_flags = sb->s_d_flags;
> dentry->d_fsdata = NULL;
> INIT_HLIST_BL_NODE(&dentry->d_hash);
> INIT_LIST_HEAD(&dentry->d_lru);
> INIT_HLIST_HEAD(&dentry->d_children);
> INIT_HLIST_NODE(&dentry->d_u.d_alias);
> INIT_HLIST_NODE(&dentry->d_sib);
> - d_set_d_op(dentry, dentry->d_sb->__s_d_op);
>
> if (dentry->d_op && dentry->d_op->d_init) {
> err = dentry->d_op->d_init(dentry);
> @@ -1850,7 +1850,9 @@ EXPORT_SYMBOL(d_set_d_op);
>
> void set_default_d_op(struct super_block *s, const struct dentry_operations *ops)
> {
> + unsigned int flags = d_op_flags(ops);
> s->__s_d_op = ops;
> + s->s_d_flags = (s->s_d_flags & ~DCACHE_OP_FLAGS) | flags;
> }
> EXPORT_SYMBOL(set_default_d_op);
>
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 23fd8b0d4e81..473a9de5fc8f 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -1392,6 +1392,7 @@ struct super_block {
> char s_sysfs_name[UUID_STRING_LEN + 1];
>
> unsigned int s_max_links;
> + unsigned int s_d_flags;
>
> /*
> * The next field is for VFS *only*. No filesystems have any business
> --
> 2.39.5
>
