mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

cirrus: handle negative pitch in cirrus_invalidate_region()

Browse Source 
cirrus_invalidate_region() calls memory_region_set_dirty()
on a per-line basis, always ranging from off_begin to
off_begin+bytesperline. With a negative pitch off_begin
marks the top most used address and thus we need to do an
initial shift backwards by a line for negative pitches of
backward blits, otherwise the first iteration covers the
line going from the start offset forwards instead of
backwards.
Additionally since the start address is inclusive, if we
shift by a full `bytesperline` we move to the first address
*not* included in the blit, so we only shift by one less
than bytesperline.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Message-id: 1485352137-29367-1-git-send-email-w.bumiller@proxmox.com

[ kraxel: codestyle fixes ]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Wolfgang Bumiller 2017-01-25 14:48:57 +01:00 committed by Gerd Hoffmann
parent a0def59428
commit f153b563f8
1 changed files with 5 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
hw/display/cirrus_vga.c
View File

@ -661,9 +661,14 @@ static void cirrus_invalidate_region(CirrusVGAState * s, int off_begin,
int off_cur;
int off_cur_end;
if (off_pitch < 0) {
off_begin -= bytesperline - 1;
}
for (y = 0; y < lines; y++) {
off_cur = off_begin;
off_cur_end = (off_cur + bytesperline) & s->cirrus_addr_mask;
assert(off_cur_end >= off_cur);
memory_region_set_dirty(&s->vga.vram, off_cur, off_cur_end - off_cur);
off_begin += off_pitch;
}