tty: vt, unify scrolling functions

Both scrup and scrdown are copies of the same code except source and
destination pointers computation. Unify those functions into a single
one named con_scroll.

Note that scrdown used step to compute the destination, while scrup
did the computation explicitly. We sticked to the latter here.

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

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index c4bf96fee32e201299ed462146d100d33b57c263..a0b7576747cd5cb837be2798d9793fafab4075dc 100644 (file)
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -315,40 +315,27 @@ void schedule_console_callback(void)
        schedule_work(&console_work);
 }
 
-static void scrup(struct vc_data *vc, unsigned int t, unsigned int b,
-               unsigned int nr)
+static void con_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
+               enum con_scroll dir, unsigned int nr)
 {
-       unsigned short *d, *s;
+       u16 *clear, *d, *s;
 
-       if (t+nr >= b)
+       if (t + nr >= b)
                nr = b - t - 1;
        if (b > vc->vc_rows || t >= b || nr < 1)
                return;
-       if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, SM_UP, nr))
+       if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, dir, nr))
                return;
-       d = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
-       s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * (t + nr));
-       scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
-       scr_memsetw(d + (b - t - nr) * vc->vc_cols, vc->vc_video_erase_char,
-                   vc->vc_size_row * nr);
-}
 
-static void scrdown(struct vc_data *vc, unsigned int t, unsigned int b,
-               unsigned int nr)
-{
-       unsigned short *s;
-       unsigned int step;
+       s = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * t);
+       d = (u16 *)(vc->vc_origin + vc->vc_size_row * (t + nr));
 
-       if (t+nr >= b)
-               nr = b - t - 1;
-       if (b > vc->vc_rows || t >= b || nr < 1)
-               return;
-       if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, SM_DOWN, nr))
-               return;
-       s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
-       step = vc->vc_cols * nr;
-       scr_memmovew(s + step, s, (b - t - nr) * vc->vc_size_row);
-       scr_memsetw(s, vc->vc_video_erase_char, 2 * step);
+       if (dir == SM_UP) {
+               clear = s + (b - t - nr) * vc->vc_cols;
+               swap(s, d);
+       }
+       scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
+       scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
 }
 
 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
@@ -1117,7 +1104,7 @@ static void lf(struct vc_data *vc)
         * if below scrolling region
         */
        if (vc->vc_y + 1 == vc->vc_bottom)
-               scrup(vc, vc->vc_top, vc->vc_bottom, 1);
+               con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
        else if (vc->vc_y < vc->vc_rows - 1) {
                vc->vc_y++;
                vc->vc_pos += vc->vc_size_row;
@@ -1132,7 +1119,7 @@ static void ri(struct vc_data *vc)
         * if above scrolling region
         */
        if (vc->vc_y == vc->vc_top)
-               scrdown(vc, vc->vc_top, vc->vc_bottom, 1);
+               con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
        else if (vc->vc_y > 0) {
                vc->vc_y--;
                vc->vc_pos -= vc->vc_size_row;
@@ -1628,7 +1615,7 @@ static void csi_L(struct vc_data *vc, unsigned int nr)
                nr = vc->vc_rows - vc->vc_y;
        else if (!nr)
                nr = 1;
-       scrdown(vc, vc->vc_y, vc->vc_bottom, nr);
+       con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_DOWN, nr);
        vc->vc_need_wrap = 0;
 }
 
@@ -1649,7 +1636,7 @@ static void csi_M(struct vc_data *vc, unsigned int nr)
                nr = vc->vc_rows - vc->vc_y;
        else if (!nr)
                nr=1;
-       scrup(vc, vc->vc_y, vc->vc_bottom, nr);
+       con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_UP, nr);
        vc->vc_need_wrap = 0;
 }