On Sat, May 22, 2021 at 07:31:55PM +0800, menglong8.dong@xxxxxxxxx wrote:
> From: Menglong Dong <dong.menglong@xxxxxxxxxx>
>
> As for the existence of 'user root' which is introduced in previous
> patch, 'rootfs_fs_type', which is used as the root of mount tree,
> is not used directly any more. So it make no sense to switch it
> between ramfs and tmpfs, just fix it with ramfs to simplify the
> code.
You also noted this could be arbitrary. I don't see why its true that
the context used for init_mount_tree() can be arbitrary. And if it can
be, then why remove it / replace it with something more NULL like?
Luis
> Signed-off-by: Menglong Dong <dong.menglong@xxxxxxxxxx>
> ---
> fs/namespace.c | 2 --
> include/linux/init.h | 1 -
> init/do_mounts.c | 18 +-----------------
> 3 files changed, 1 insertion(+), 20 deletions(-)
>
> diff --git a/fs/namespace.c b/fs/namespace.c
> index f63337828e1c..8d2b57938e3a 100644
> --- a/fs/namespace.c
> +++ b/fs/namespace.c
> @@ -17,7 +17,6 @@
> #include <linux/security.h>
> #include <linux/cred.h>
> #include <linux/idr.h>
> -#include <linux/init.h> /* init_rootfs */
> #include <linux/fs_struct.h> /* get_fs_root et.al. */
> #include <linux/fsnotify.h> /* fsnotify_vfsmount_delete */
> #include <linux/file.h>
> @@ -4241,7 +4240,6 @@ void __init mnt_init(void)
> if (!fs_kobj)
> printk(KERN_WARNING "%s: kobj create error\n", __func__);
> shmem_init();
> - init_rootfs();
> init_mount_tree();
> }
>
> diff --git a/include/linux/init.h b/include/linux/init.h
> index 045ad1650ed1..86bd92bb9550 100644
> --- a/include/linux/init.h
> +++ b/include/linux/init.h
> @@ -148,7 +148,6 @@ extern unsigned int reset_devices;
> /* used by init/main.c */
> void setup_arch(char **);
> void prepare_namespace(void);
> -void __init init_rootfs(void);
> extern struct file_system_type rootfs_fs_type;
>
> #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
> diff --git a/init/do_mounts.c b/init/do_mounts.c
> index 943cb58846fb..6d1253f75bb0 100644
> --- a/init/do_mounts.c
> +++ b/init/do_mounts.c
> @@ -689,24 +689,8 @@ void __init init_user_rootfs(void)
> }
> }
>
> -static bool is_tmpfs;
> -static int rootfs_init_fs_context(struct fs_context *fc)
> -{
> - if (IS_ENABLED(CONFIG_TMPFS) && is_tmpfs)
> - return shmem_init_fs_context(fc);
> -
> - return ramfs_init_fs_context(fc);
> -}
> -
> struct file_system_type rootfs_fs_type = {
> .name = "rootfs",
> - .init_fs_context = rootfs_init_fs_context,
> + .init_fs_context = ramfs_init_fs_context,
> .kill_sb = kill_litter_super,
> };
You mentioned
> -
> -void __init init_rootfs(void)
> -{
> - if (IS_ENABLED(CONFIG_TMPFS) && !saved_root_name[0] &&
> - (!root_fs_names || strstr(root_fs_names, "tmpfs")))
> - is_tmpfs = true;
> -}
> --
> 2.31.1
>
