vfs: Provide sb->s_iflags settings in fs_context struct

Provide a field in the fs_context struct through which bits in the
sb->s_iflags superblock field can be set.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-fsdevel@vger.kernel.org

fs/super.c

@@ -540,6 +540,7 @@ struct super_block *sget_fc(struct fs_context *fc,
 	}
 	fc->s_fs_info = NULL;
 	s->s_type = fc->fs_type;
+	s->s_iflags |= fc->s_iflags;
 	strlcpy(s->s_id, s->s_type->name, sizeof(s->s_id));
 	list_add_tail(&s->s_list, &super_blocks);
 	hlist_add_head(&s->s_instances, &s->s_type->fs_supers);

include/linux/fs_context.h

@@ -103,6 +103,7 @@ struct fs_context {
 	void			*s_fs_info;	/* Proposed s_fs_info */
 	unsigned int		sb_flags;	/* Proposed superblock flags (SB_*) */
 	unsigned int		sb_flags_mask;	/* Superblock flags that were changed */
+	unsigned int		s_iflags;	/* OR'd with sb->s_iflags */
 	unsigned int		lsm_flags;	/* Information flags from the fs to the LSM */
 	enum fs_context_purpose	purpose:8;
 	enum fs_context_phase	phase:8;	/* The phase the context is in */