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>
This commit is contained in:
Jiri Slaby 2016-10-03 11:18:36 +02:00 committed by Greg Kroah-Hartman
parent 35cc56f9a3
commit 210fd7460e

View File

@ -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)