debian/patches/extra/0001-cirrus-handle-negative-pitch-in-cirrus_invalidate_re.patch

   1 From b3ce5aeaacdd0cec5bab1d83ee24bae73b0dd506 Mon Sep 17 00:00:00 2001
   2 From: Wolfgang Bumiller <w.bumiller@proxmox.com>
   3 Date: Wed, 25 Jan 2017 14:48:57 +0100
   4 Subject: [PATCH 1/4] cirrus: handle negative pitch in
   5  cirrus_invalidate_region()
   6
   7 cirrus_invalidate_region() calls memory_region_set_dirty()
   8 on a per-line basis, always ranging from off_begin to
   9 off_begin+bytesperline. With a negative pitch off_begin
  10 marks the top most used address and thus we need to do an
  11 initial shift backwards by a line for negative pitches of
  12 backward blits, otherwise the first iteration covers the
  13 line going from the start offset forwards instead of
  14 backwards.
  15 Additionally since the start address is inclusive, if we
  16 shift by a full `bytesperline` we move to the first address
  17 *not* included in the blit, so we only shift by one less
  18 than bytesperline.
  19
  20 Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
  21 Message-id: 1485352137-29367-1-git-send-email-w.bumiller@proxmox.com
  22
  23 [ kraxel: codestyle fixes ]
  24
  25 Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
  26 ---
  27  hw/display/cirrus_vga.c | 5 +++++
  28  1 file changed, 5 insertions(+)
  29
  30 diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c
  31 index 379910d..0f05e45 100644
  32 --- a/hw/display/cirrus_vga.c
  33 +++ b/hw/display/cirrus_vga.c
  34 @@ -661,9 +661,14 @@ static void cirrus_invalidate_region(CirrusVGAState * s, int off_begin,
  35      int off_cur;
  36      int off_cur_end;
  37
  38 +    if (off_pitch < 0) {
  39 +        off_begin -= bytesperline - 1;
  40 +    }
  41 +
  42      for (y = 0; y < lines; y++) {
  43         off_cur = off_begin;
  44         off_cur_end = (off_cur + bytesperline) & s->cirrus_addr_mask;
  45 +        assert(off_cur_end >= off_cur);
  46          memory_region_set_dirty(&s->vga.vram, off_cur, off_cur_end - off_cur);
  47         off_begin += off_pitch;
  48      }
  49 --
  50 2.1.4
  51