VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)

Firstly by applying the following with coccinelle's spatch:

	@@ expression SB; @@
	-SB->s_flags & MS_RDONLY
	+sb_rdonly(SB)

to effect the conversion to sb_rdonly(sb), then by applying:

	@@ expression A, SB; @@
	(
	-(!sb_rdonly(SB)) && A
	+!sb_rdonly(SB) && A
	|
	-A != (sb_rdonly(SB))
	+A != sb_rdonly(SB)
	|
	-A == (sb_rdonly(SB))
	+A == sb_rdonly(SB)
	|
	-!(sb_rdonly(SB))
	+!sb_rdonly(SB)
	|
	-A && (sb_rdonly(SB))
	+A && sb_rdonly(SB)
	|
	-A || (sb_rdonly(SB))
	+A || sb_rdonly(SB)
	|
	-(sb_rdonly(SB)) != A
	+sb_rdonly(SB) != A
	|
	-(sb_rdonly(SB)) == A
	+sb_rdonly(SB) == A
	|
	-(sb_rdonly(SB)) && A
	+sb_rdonly(SB) && A
	|
	-(sb_rdonly(SB)) || A
	+sb_rdonly(SB) || A
	)

	@@ expression A, B, SB; @@
	(
	-(sb_rdonly(SB)) ? 1 : 0
	+sb_rdonly(SB)
	|
	-(sb_rdonly(SB)) ? A : B
	+sb_rdonly(SB) ? A : B
	)

to remove left over excess bracketage and finally by applying:

	@@ expression A, SB; @@
	(
	-(A & MS_RDONLY) != sb_rdonly(SB)
	+(bool)(A & MS_RDONLY) != sb_rdonly(SB)
	|
	-(A & MS_RDONLY) == sb_rdonly(SB)
	+(bool)(A & MS_RDONLY) == sb_rdonly(SB)
	)

to make comparisons against the result of sb_rdonly() (which is a bool)
work correctly.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/fs/namespace.c b/fs/namespace.c
index f8893dc..e42c9ab 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -275,7 +275,7 @@ int __mnt_is_readonly(struct vfsmount *mnt)
 {
 	if (mnt->mnt_flags & MNT_READONLY)
 		return 1;
-	if (mnt->mnt_sb->s_flags & MS_RDONLY)
+	if (sb_rdonly(mnt->mnt_sb))
 		return 1;
 	return 0;
 }
@@ -1534,7 +1534,7 @@ static int do_umount(struct mount *mnt, int flags)
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;
 		down_write(&sb->s_umount);
-		if (!(sb->s_flags & MS_RDONLY))
+		if (!sb_rdonly(sb))
 			retval = do_remount_sb(sb, MS_RDONLY, NULL, 0);
 		up_write(&sb->s_umount);
 		return retval;
@@ -3300,7 +3300,7 @@ static bool mnt_already_visible(struct mnt_namespace *ns, struct vfsmount *new,
 		mnt_flags = mnt->mnt.mnt_flags;
 
 		/* Don't miss readonly hidden in the superblock flags */
-		if (mnt->mnt.mnt_sb->s_flags & MS_RDONLY)
+		if (sb_rdonly(mnt->mnt.mnt_sb))
 			mnt_flags |= MNT_LOCK_READONLY;
 
 		/* Verify the mount flags are equal to or more permissive