On Wed, Jun 14, 2023 at 10:49:06AM +0300, Amir Goldstein wrote:
> +static struct file *__alloc_file(int flags, const struct cred *cred)
> +{
> + struct file *f;
> + int error;
> +
> + f = kmem_cache_zalloc(filp_cachep, GFP_KERNEL);
> + if (unlikely(!f))
> + return ERR_PTR(-ENOMEM);
> +
> + error = init_file(f, flags, cred);
> + if (unlikely(error))
> + return ERR_PTR(error);
> +
> return f;
Nit: is there much of a point in keeping this now very trivial helper
instead of open coding it in the two callers?
> +/*
> + * Variant of alloc_empty_file() that allocates a backing_file container
> + * and doesn't check and modify nr_files.
> + *
> + * Should not be used unless there's a very good reason to do so.
I'm not sure this comment is all that helpful.. I'd rather explain
when it should be used (i.e. only from open_backing_file) then when
it should not..
> -struct file *open_with_fake_path(const struct path *path, int flags,
> - struct inode *inode, const struct cred *cred)
> +struct file *open_backing_file(const struct path *path, int flags,
> + const struct path *real_path,
> + const struct cred *cred)
Please write a big fat comment on where this function should and should
not be used and how it works.
> +struct path *backing_file_real_path(struct file *f);
> +static inline const struct path *f_real_path(struct file *f)
> +{
> + if (unlikely(f->f_mode & FMODE_BACKING))
> + return backing_file_real_path(f);
> + else
> + return &f->f_path;
> +}
Nit: no need for the else here.
