tty: vt, compute vc offsets in advance

Only improves readability, no functional changes.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 2eab714aab67..3cb6504b41d3 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -4283,6 +4283,9 @@ void vc_scrolldelta_helper(struct vc_data *c, int lines,
                 unsigned int rolled_over, void *base, unsigned int size)
 {
         unsigned long ubase = (unsigned long)base;
+        ptrdiff_t scr_end = (void *)c->vc_scr_end - base;
+        ptrdiff_t vorigin = (void *)c->vc_visible_origin - base;
+        ptrdiff_t origin = (void *)c->vc_origin - base;
         int margin = c->vc_size_row * 4;
         int ul, we, p, st;
 
@@ -4293,17 +4296,16 @@ void vc_scrolldelta_helper(struct vc_data *c, int lines,
         }
 
         /* Do we have already enough to allow jumping from 0 to the end? */
-        if (rolled_over > (c->vc_scr_end - ubase) + margin) {
-                ul = c->vc_scr_end - ubase;
+        if (rolled_over > scr_end + margin) {
+                ul = scr_end;
                 we = rolled_over + c->vc_size_row;
         } else {
                 ul = 0;
                 we = size;
         }
 
-        p = (c->vc_visible_origin - ubase - ul + we) % we +
-                lines * c->vc_size_row;
-        st = (c->vc_origin - ubase - ul + we) % we;
+        p = (vorigin - ul + we) % we + lines * c->vc_size_row;
+        st = (origin - ul + we) % we;
 
         /* Only a little piece would be left? Show all incl. the piece! */
         if (st < 2 * margin)