Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   menglong8.dong@gmail.com
To:     mcgrof@kernel.org, josh@joshtriplett.org
Cc:     viro@zeniv.linux.org.uk, keescook@chromium.org,
        samitolvanen@google.com, ojeda@kernel.org, johan@kernel.org,
        bhelgaas@google.com, masahiroy@kernel.org,
        dong.menglong@zte.com.cn, joe@perches.com, axboe@kernel.dk,
        hare@suse.de, jack@suse.cz, tj@kernel.org,
        gregkh@linuxfoundation.org, song@kernel.org, neilb@suse.de,
        akpm@linux-foundation.org, f.fainelli@gmail.com, arnd@arndb.de,
        linux@rasmusvillemoes.dk, wangkefeng.wang@huawei.com,
        brho@google.com, mhiramat@kernel.org, rostedt@goodmis.org,
        vbabka@suse.cz, glider@google.com, pmladek@suse.com,
        chris@chrisdown.name, ebiederm@xmission.com, jojing64@gmail.com,
        terrelln@fb.com, geert@linux-m68k.org, mingo@kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        jeyu@kernel.org
Subject: [PATCH v2 3/3] init/do_mounts.c: fix rootfs_fs_type with ramfs
Date:   Tue, 25 May 2021 22:15:24 +0800
Message-Id: <20210525141524.3995-4-dong.menglong@zte.com.cn>
In-Reply-To: <20210525141524.3995-1-dong.menglong@zte.com.cn>
References: <20210525141524.3995-1-dong.menglong@zte.com.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Menglong Dong <dong.menglong@zte.com.cn>

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 make it tmpfs
while 'INITRAMFS_USER_ROOT' is enabled.

Make 'rootfs_fs_type' ramfs when 'INITRAMFS_USER_ROOT' enabled.

Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
---
 include/linux/init.h |  5 +++++
 init/do_mounts.c     | 10 +++++++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/linux/init.h b/include/linux/init.h
index 045ad1650ed1..d65b12fe438c 100644
--- a/include/linux/init.h
+++ b/include/linux/init.h
@@ -148,7 +148,12 @@ extern unsigned int reset_devices;
 /* used by init/main.c */
 void setup_arch(char **);
 void prepare_namespace(void);
+#ifndef CONFIG_INITRAMFS_USER_ROOT
 void __init init_rootfs(void);
+#else
+static inline void __init init_rootfs(void) { }
+#endif
+
 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 2fd168cca480..74f5b0fc8bdf 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -716,7 +716,14 @@ void __init init_user_rootfs(void)
 		}
 	}
 }
-#endif
+
+struct file_system_type rootfs_fs_type = {
+	.name		= "rootfs",
+	.init_fs_context = ramfs_init_fs_context,
+	.kill_sb	= kill_litter_super,
+};
+
+#else
 
 static bool is_tmpfs;
 static int rootfs_init_fs_context(struct fs_context *fc)
@@ -739,3 +746,4 @@ void __init init_rootfs(void)
 		(!root_fs_names || strstr(root_fs_names, "tmpfs")))
 		is_tmpfs = true;
 }
+#endif
-- 
2.32.0.rc0