[Qemu-devel] [PATCH 09/11] xen: only track the linear framebuffer

[Alexander Graf <agraf@suse.de>]

From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Xen can only do dirty bit tracking for one memory region, so we should
explicitly avoid trying to track anything but the vga vram region.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
---
 xen-all.c |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/xen-all.c b/xen-all.c
index 75a82c2..fe75ddd 100644
--- a/xen-all.c
+++ b/xen-all.c
@@ -215,6 +215,7 @@ static int xen_add_to_physmap(XenIOState *state,
     int rc = 0;
     XenPhysmap *physmap = NULL;
     target_phys_addr_t pfn, start_gpfn;
+    RAMBlock *block;
 
     if (get_physmapping(state, start_addr, size)) {
         return 0;
@@ -223,6 +224,19 @@ static int xen_add_to_physmap(XenIOState *state,
         return -1;
     }
 
+    /* Xen can only handle a single dirty log region for now and we want
+     * the linear framebuffer to be that region.
+     * Avoid tracking any regions that is not videoram and avoid tracking
+     * the legacy vga region. */
+    QLIST_FOREACH(block, &ram_list.blocks, next) {
+        if (!strcmp(block->idstr, "vga.vram") && block->offset == phys_offset
+                && start_addr > 0xbffff) {
+            goto go_physmap;
+        }
+    }
+    return -1;
+
+go_physmap:
     DPRINTF("mapping vram to %llx - %llx, from %llx\n",
             start_addr, start_addr + size, phys_offset);
 
-- 
1.6.0.2