fs: cleanup files_lock locking

fs: cleanup files_lock locking

Lock tty_files with a new spinlock, tty_files_lock; provide helpers to
manipulate the per-sb files list; unexport the files_lock spinlock.

Cc: linux-kernel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 2 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 42043f96e54f..bd7da0f0ccf3 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2170,7 +2170,7 @@ static inline void flush_unauthorized_files(const struct cred *cred,
 
         tty = get_current_tty();
         if (tty) {
-                file_list_lock();
+                spin_lock(&tty_files_lock);
                 if (!list_empty(&tty->tty_files)) {
                         struct inode *inode;
 
@@ -2186,7 +2186,7 @@ static inline void flush_unauthorized_files(const struct cred *cred,
                                 drop_tty = 1;
                         }
                 }
-                file_list_unlock();
+                spin_unlock(&tty_files_lock);
                 tty_kref_put(tty);
         }
         /* Reset controlling tty. */