[PATCH 07/24] init: refactor mount_root

Christoph Hellwig
2023-05-31T12:57:18Z

Provide stubs for all the lower level mount helpers, and just switch
on ROOT_DEV in the main function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
init/do_mounts.c | 104 +++++++++++++++++++++++++----------------------
1 file changed, 56 insertions(+), 48 deletions(-)

diff --git a/init/do_mounts.c b/init/do_mounts.c
index a2c0baace0992c..e708b02d9d6566 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -453,15 +453,14 @@ void __init mount_root_generic(char *name, int flags)
#define NFSROOT_TIMEOUT_MAX 30
#define NFSROOT_RETRY_MAX 5

-static int __init mount_nfs_root(void)
+static void __init mount_nfs_root(void)
{
char *root_dev, *root_data;
unsigned int timeout;
- int try, err;
+ int try;

- err = nfs_root_data(&root_dev, &root_data);
- if (err != 0)
- return 0;
+ if (nfs_root_data(&root_dev, &root_data))
+ goto fail;

/*
* The server or network may not be ready, so try several
@@ -470,10 +469,8 @@ static int __init mount_nfs_root(void)
*/
timeout = NFSROOT_TIMEOUT_MIN;
for (try = 1; ; try++) {
- err = do_mount_root(root_dev, "nfs",
- root_mountflags, root_data);
- if (err == 0)
- return 1;
+ if (!do_mount_root(root_dev, "nfs", root_mountflags, root_data))
+ return;
if (try > NFSROOT_RETRY_MAX)
break;

@@ -483,9 +480,14 @@ static int __init mount_nfs_root(void)
if (timeout > NFSROOT_TIMEOUT_MAX)
timeout = NFSROOT_TIMEOUT_MAX;
}
- return 0;
+fail:
+ pr_err("VFS: Unable to mount root fs via NFS.\n");
}
-#endif
+#else
+static inline void mount_nfs_root(void)
+{
+}
+#endif /* CONFIG_ROOT_NFS */

#ifdef CONFIG_CIFS_ROOT

@@ -495,22 +497,20 @@ extern int cifs_root_data(char **dev, char **opts);
#define CIFSROOT_TIMEOUT_MAX 30
#define CIFSROOT_RETRY_MAX 5

-static int __init mount_cifs_root(void)
+static void __init mount_cifs_root(void)
{
char *root_dev, *root_data;
unsigned int timeout;
- int try, err;
+ int try;

- err = cifs_root_data(&root_dev, &root_data);
- if (err != 0)
- return 0;
+ if (cifs_root_data(&root_dev, &root_data))
+ goto fail;

timeout = CIFSROOT_TIMEOUT_MIN;
for (try = 1; ; try++) {
- err = do_mount_root(root_dev, "cifs", root_mountflags,
- root_data);
- if (err == 0)
- return 1;
+ if (!do_mount_root(root_dev, "cifs", root_mountflags,
+ root_data))
+ return;
if (try > CIFSROOT_RETRY_MAX)
break;

@@ -519,9 +519,14 @@ static int __init mount_cifs_root(void)
if (timeout > CIFSROOT_TIMEOUT_MAX)
timeout = CIFSROOT_TIMEOUT_MAX;
}
- return 0;
+fail:
+ pr_err("VFS: Unable to mount root fs via SMB.\n");
}
-#endif
+#else
+static inline void mount_cifs_root(void)
+{
+}
+#endif /* CONFIG_CIFS_ROOT */

static bool __init fs_is_nodev(char *fstype)
{
@@ -563,35 +568,38 @@ static int __init mount_nodev_root(void)
return err;
}

-void __init mount_root(void)
-{
-#ifdef CONFIG_ROOT_NFS
- if (ROOT_DEV == Root_NFS) {
- if (!mount_nfs_root())
- printk(KERN_ERR "VFS: Unable to mount root fs via NFS.\n");
- return;
- }
-#endif
-#ifdef CONFIG_CIFS_ROOT
- if (ROOT_DEV == Root_CIFS) {
- if (!mount_cifs_root())
- printk(KERN_ERR "VFS: Unable to mount root fs via SMB.\n");
- return;
- }
-#endif
- if (ROOT_DEV == 0 && root_device_name && root_fs_names) {
- if (mount_nodev_root() == 0)
- return;
- }
#ifdef CONFIG_BLOCK
- {
- int err = create_dev("/dev/root", ROOT_DEV);
+static void __init mount_block_root(void)
+{
+ int err = create_dev("/dev/root", ROOT_DEV);
+
+ if (err < 0)
+ pr_emerg("Failed to create /dev/root: %d\n", err);
+ mount_root_generic("/dev/root", root_mountflags);
+}
+#else
+static inline void mount_block_root(void)
+{
+}
+#endif /* CONFIG_BLOCK */

- if (err < 0)
- pr_emerg("Failed to create /dev/root: %d\n", err);
- mount_root_generic("/dev/root", root_mountflags);
+void __init mount_root(void)
+{
+ switch (ROOT_DEV) {
+ case Root_NFS:
+ mount_nfs_root();
+ break;
+ case Root_CIFS:
+ mount_cifs_root();
+ break;
+ case 0:
+ if (root_device_name && root_fs_names && mount_nodev_root() == 0)
+ break;
+ fallthrough;
+ default:
+ mount_block_root();
+ break;
}
-#endif
}

/*
--
2.39.2