VFS: Clean up shared mount flag propagation

The handling of mount flags in set_mnt_shared() got a little tangled
up during previous cleanups, with the following problems:

* MNT_PNODE_MASK is defined as a literal constant when it should be a
bitwise xor of other MNT_* flags
* set_mnt_shared() clears and then sets MNT_SHARED (part of MNT_PNODE_MASK)
* MNT_PNODE_MASK could use a comment in mount.h
* MNT_PNODE_MASK is a terrible name, change to MNT_SHARED_MASK

This patch fixes these problems.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index 25c1dcf9e9eb..d25d4602ab50 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1538,7 +1538,7 @@ static int do_remount(struct path *path, int flags, int mnt_flags,
                 err = do_remount_sb(sb, flags, data, 0);
         if (!err) {
                 spin_lock(&vfsmount_lock);
-                mnt_flags |= path->mnt->mnt_flags & MNT_PNODE_MASK;
+                mnt_flags |= path->mnt->mnt_flags & MNT_PROPAGATION_MASK;
                 path->mnt->mnt_flags = mnt_flags;
                 spin_unlock(&vfsmount_lock);
         }