vt: push down tioclinux cases

Some of this ventures into selection which is still a complete lost cause. We
are not making it any worse. It's completely busted anyway.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 18 insertions, 8 deletions

diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c
index 738e45a35131..2a5091670927 100644
--- a/drivers/tty/vt/selection.c
+++ b/drivers/tty/vt/selection.c
@@ -75,7 +75,7 @@ clear_selection(void) {
 
 /*
  * User settable table: what characters are to be considered alphabetic?
- * 256 bits
+ * 256 bits. FIXME: Needs a locking model.
  */
 static u32 inwordLut[8]={
   0x00000000, /* control chars     */
@@ -307,7 +307,8 @@ int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *t
  * queue of the tty associated with the current console.
  * Invoked by ioctl().
  *
- * Locking: always called with BTM from vt_ioctl
+ * Locking: called without locks. Calls the ldisc wrongly with
+ * unsafe methods,
  */
 int paste_selection(struct tty_struct *tty)
 {
@@ -322,13 +323,12 @@ int paste_selection(struct tty_struct *tty)
         poke_blanked_console();
         console_unlock();
 
+        /* FIXME: wtf is this supposed to achieve ? */
         ld = tty_ldisc_ref(tty);
-        if (!ld) {
-                tty_unlock();
+        if (!ld)
                 ld = tty_ldisc_ref_wait(tty);
-                tty_lock();
-        }
 
+        /* FIXME: this is completely unsafe */
         add_wait_queue(&vc->paste_wait, &wait);
         while (sel_buffer && sel_buffer_lth > pasted) {
                 set_current_state(TASK_INTERRUPTIBLE);
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index ce2b82343620..ab7385e526af 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -2637,11 +2637,15 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
                         ret = __put_user(data, p);
                         break;
                 case TIOCL_GETMOUSEREPORTING:
+                        console_lock(); /* May be overkill */
                         data = mouse_reporting();
+                        console_unlock();
                         ret = __put_user(data, p);
                         break;
                 case TIOCL_SETVESABLANK:
+                        console_lock();
                         ret = set_vesa_blanking(p);
+                        console_unlock();
                         break;
                 case TIOCL_GETKMSGREDIRECT:
                         data = vt_get_kmsg_redirect();
@@ -2658,13 +2662,21 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
                         }
                         break;
                 case TIOCL_GETFGCONSOLE:
+                        /* No locking needed as this is a transiently
+                           correct return anyway if the caller hasn't
+                           disabled switching */
                         ret = fg_console;
                         break;
                 case TIOCL_SCROLLCONSOLE:
                         if (get_user(lines, (s32 __user *)(p+4))) {
                                 ret = -EFAULT;
                         } else {
+                                /* Need the console lock here. Note that lots
+                                   of other calls need fixing before the lock
+                                   is actually useful ! */
+                                console_lock();
                                 scrollfront(vc_cons[fg_console].d, lines);
+                                console_unlock();
                                 ret = 0;
                         }
                         break;
diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c
index e05094d76344..c6720be8d210 100644
--- a/drivers/tty/vt/vt_ioctl.c
+++ b/drivers/tty/vt/vt_ioctl.c
@@ -298,9 +298,7 @@ int vt_ioctl(struct tty_struct *tty,
  
         switch (cmd) {
         case TIOCLINUX:
-                tty_lock();
                 ret = tioclinux(tty, arg);
-                tty_unlock();
                 break;
         case KIOCSOUND:
                 if (!perm)