[V2] modesetting: code refactor for PRIME sync

[Jim Qu]

The X will be crashed on the system with other DDX driver,
such as amdgpu.

show the log like:

randr: falling back to unsynchronized pixmap sharing
(EE)
(EE) Backtrace:
(EE) 0: /usr/lib/xorg/Xorg (xorg_backtrace+0x4e)
(EE) 1: /usr/lib/xorg/Xorg (0x55cb0151a000+0x1b5ce9)
(EE) 2: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7f1587a1d000+0x11390)
(EE)
(EE) Segmentation fault at address 0x0
(EE)

The issue is that modesetting as the master, and amdgpu as the slave.
Thus, when the master attempts to access pSlavePixPriv in ms_dirty_update(),
problems result due to the fact that it's accessing AMD's 'ppriv' using the
modesetting structure definition.

Apart from fixing crash issue, the patch fix other issue in master interface
in which driver should refer to master pixmap.

Change-Id: I274633c9657c3621c95efd7632355662b9f5052c
Signed-off-by: Jim Qu <Jim.Qu at amd.com>
---
 hw/xfree86/drivers/modesetting/driver.c | 36 +++++++++++++++++----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

diff --git a/hw/xfree86/drivers/modesetting/driver.c b/hw/xfree86/drivers/modesetting/driver.c
index 9362370..792dfb6 100644
--- a/hw/xfree86/drivers/modesetting/driver.c
+++ b/hw/xfree86/drivers/modesetting/driver.c
@@ -640,19 +640,21 @@ ms_dirty_update(ScreenPtr screen, int *timeout)
     xorg_list_for_each_entry(ent, &screen->pixmap_dirty_list, ent) {
         region = DamageRegion(ent->damage);
         if (RegionNotEmpty(region)) {
-            msPixmapPrivPtr ppriv =
-                msGetPixmapPriv(&ms->drmmode, ent->slave_dst);
+            if (!screen->isGPU) {
+                   msPixmapPrivPtr ppriv =
+                    msGetPixmapPriv(&ms->drmmode, ent->slave_dst->master_pixmap);
 
-            if (ppriv->notify_on_damage) {
-                ppriv->notify_on_damage = FALSE;
+                if (ppriv->notify_on_damage) {
+                    ppriv->notify_on_damage = FALSE;
 
-                ent->slave_dst->drawable.pScreen->
-                    SharedPixmapNotifyDamage(ent->slave_dst);
-            }
+                    ent->slave_dst->drawable.pScreen->
+                        SharedPixmapNotifyDamage(ent->slave_dst);
+                }
 
-            /* Requested manual updating */
-            if (ppriv->defer_dirty_update)
-                continue;
+                /* Requested manual updating */
+                if (ppriv->defer_dirty_update)
+                    continue;
+            }
 
             redisplay_dirty(screen, ent, timeout);
             DamageEmpty(ent->damage);
@@ -1251,8 +1253,8 @@ msStartFlippingPixmapTracking(RRCrtcPtr crtc, DrawablePtr src,
     ScreenPtr pScreen = src->pScreen;
     modesettingPtr ms = modesettingPTR(xf86ScreenToScrn(pScreen));
 
-    msPixmapPrivPtr ppriv1 = msGetPixmapPriv(&ms->drmmode, slave_dst1),
-                    ppriv2 = msGetPixmapPriv(&ms->drmmode, slave_dst2);
+    msPixmapPrivPtr ppriv1 = msGetPixmapPriv(&ms->drmmode, slave_dst1->master_pixmap),
+                    ppriv2 = msGetPixmapPriv(&ms->drmmode, slave_dst2->master_pixmap);
 
     if (!PixmapStartDirtyTracking(src, slave_dst1, x, y,
                                   dst_x, dst_y, rotation)) {
@@ -1280,10 +1282,10 @@ msStartFlippingPixmapTracking(RRCrtcPtr crtc, DrawablePtr src,
 static Bool
 msPresentSharedPixmap(PixmapPtr slave_dst)
 {
-    ScreenPtr pScreen = slave_dst->drawable.pScreen;
+    ScreenPtr pScreen = slave_dst->master_pixmap->drawable.pScreen;
     modesettingPtr ms = modesettingPTR(xf86ScreenToScrn(pScreen));
 
-    msPixmapPrivPtr ppriv = msGetPixmapPriv(&ms->drmmode, slave_dst);
+    msPixmapPrivPtr ppriv = msGetPixmapPriv(&ms->drmmode, slave_dst->master_pixmap);
 
     RegionPtr region = DamageRegion(ppriv->dirty->damage);
 
@@ -1304,8 +1306,8 @@ msStopFlippingPixmapTracking(DrawablePtr src,
     ScreenPtr pScreen = src->pScreen;
     modesettingPtr ms = modesettingPTR(xf86ScreenToScrn(pScreen));
 
-    msPixmapPrivPtr ppriv1 = msGetPixmapPriv(&ms->drmmode, slave_dst1),
-                    ppriv2 = msGetPixmapPriv(&ms->drmmode, slave_dst2);
+    msPixmapPrivPtr ppriv1 = msGetPixmapPriv(&ms->drmmode, slave_dst1->master_pixmap),
+                    ppriv2 = msGetPixmapPriv(&ms->drmmode, slave_dst2->master_pixmap);
 
     Bool ret = TRUE;
 
@@ -1471,7 +1473,7 @@ msRequestSharedPixmapNotifyDamage(PixmapPtr ppix)
     ScrnInfoPtr scrn = xf86ScreenToScrn(screen);
     modesettingPtr ms = modesettingPTR(scrn);
 
-    msPixmapPrivPtr ppriv = msGetPixmapPriv(&ms->drmmode, ppix);
+    msPixmapPrivPtr ppriv = msGetPixmapPriv(&ms->drmmode, ppix->master_pixmap);
 
     ppriv->notify_on_damage = TRUE;
 
-- 
2.7.4