teach vfs_get_tree() to handle subtype, switch do_new_mount() to it
Roll the handling of subtypes into do_new_mount() and vfs_get_tree(). The
former determines any subtype string and hangs it off the fs_context; the
latter applies it.
Make do_new_mount() create, parameterise and commit an fs_context and
create a mount for itself rather than calling vfs_kern_mount().
[AV -- missing kstrdup()]
[AV -- ... and no kstrdup() if we get to setting ->s_submount - we
simply transfer it from fc, leaving NULL behind]
[AV -- constify ->s_submount, while we are at it]
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/super.c b/fs/super.c
index fc38872..b91b6df 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1262,6 +1262,11 @@ int vfs_get_tree(struct fs_context *fc)
sb = fc->root->d_sb;
WARN_ON(!sb->s_bdi);
+ if (fc->subtype && !sb->s_subtype) {
+ sb->s_subtype = fc->subtype;
+ fc->subtype = NULL;
+ }
+
/*
* Write barrier is for super_cache_count(). We place it before setting
* SB_BORN as the data dependency between the two functions is the