[Qemu-devel] [PATCH 05/22] memory: return bitmap from memory_region_is_logging

[Paolo Bonzini <pbonzini@redhat.com>]

For now it only returns (1 << DIRTY_MEMORY_VGA) or 0, but this
will change soon so adjust the callers.

Listeners check for "any bit except migration", which is handled
via the global start/stop listener callbacks.  This in practice
means VGA because the code bitmap is TCG-specific; however, be
explicit, as for example things would be different if vhost ever
ran with TCG.

Instead, the VMware VGA is looking explicitly for DIRTY_MEMORY_VGA.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
        This is the ugliest patch in the series.  My long-term plan
        is to get rid of the global start/stop hooks in the
        MemoryListeners.

 hw/display/vmware_vga.c | 2 +-
 hw/virtio/vhost.c       | 3 ++-
 include/exec/memory.h   | 5 +++--
 kvm-all.c               | 3 ++-
 memory.c                | 2 +-
 xen-hvm.c               | 3 ++-
 6 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c
index c17ddd1..93d7426 100644
--- a/hw/display/vmware_vga.c
+++ b/hw/display/vmware_vga.c
@@ -1124,7 +1124,7 @@ static void vmsvga_update_display(void *opaque)
      * Is it more efficient to look at vram VGA-dirty bits or wait
      * for the driver to issue SVGA_CMD_UPDATE?
      */
-    if (memory_region_is_logging(&s->vga.vram)) {
+    if (memory_region_is_logging(&s->vga.vram) & (1 << DIRTY_MEMORY_VGA)) {
         vga_sync_dirty_bitmap(&s->vga);
         dirty = memory_region_get_dirty(&s->vga.vram, 0,
             surface_stride(surface) * surface_height(surface),
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 5a12861..59321ee 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -377,7 +377,8 @@ static void vhost_set_memory(MemoryListener *listener,
                                          memory_listener);
     hwaddr start_addr = section->offset_within_address_space;
     ram_addr_t size = int128_get64(section->size);
-    bool log_dirty = memory_region_is_logging(section->mr);
+    bool log_dirty =
+        memory_region_is_logging(section->mr) & ~(1 << DIRTY_MEMORY_MIGRATION);
     int s = offsetof(struct vhost_memory, regions) +
         (dev->mem->nregions + 1) * sizeof dev->mem->regions[0];
     void *ram;
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 081f7d6..8d5feb2 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -569,11 +569,12 @@ const char *memory_region_name(const MemoryRegion *mr);
 /**
  * memory_region_is_logging: return whether a memory region is logging writes
  *
- * Returns %true if the memory region is logging writes
+ * Returns a bitmap of clients for which the memory region is logging writes.
+ * Right now this will be either 0 or (1 << DIRTY_MEMORY_VGA).
  *
  * @mr: the memory region being queried
  */
-bool memory_region_is_logging(MemoryRegion *mr);
+uint8_t memory_region_is_logging(MemoryRegion *mr);
 
 /**
  * memory_region_is_rom: check whether a memory region is ROM
diff --git a/kvm-all.c b/kvm-all.c
index 335438a..6962653 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -663,7 +663,8 @@ static void kvm_set_phys_mem(MemoryRegionSection *section, bool add)
     KVMSlot *mem, old;
     int err;
     MemoryRegion *mr = section->mr;
-    bool log_dirty = memory_region_is_logging(mr);
+    bool log_dirty =
+        memory_region_is_logging(mr) & ~(1 << DIRTY_MEMORY_MIGRATION);
     bool writeable = !mr->readonly && !mr->rom_device;
     bool readonly_flag = mr->readonly || memory_region_is_romd(mr);
     hwaddr start_addr = section->offset_within_address_space;
diff --git a/memory.c b/memory.c
index e688f5e..45606bc 100644
--- a/memory.c
+++ b/memory.c
@@ -1318,7 +1318,7 @@ bool memory_region_is_skip_dump(MemoryRegion *mr)
     return mr->skip_dump;
 }
 
-bool memory_region_is_logging(MemoryRegion *mr)
+uint8_t memory_region_is_logging(MemoryRegion *mr)
 {
     return mr->dirty_log_mask;
 }
diff --git a/xen-hvm.c b/xen-hvm.c
index 315864c..acd89c8 100644
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -488,7 +488,8 @@ static void xen_set_memory(struct MemoryListener *listener,
     XenIOState *state = container_of(listener, XenIOState, memory_listener);
     hwaddr start_addr = section->offset_within_address_space;
     ram_addr_t size = int128_get64(section->size);
-    bool log_dirty = memory_region_is_logging(section->mr);
+    bool log_dirty =
+        memory_region_is_logging(section->mr) & ~(1 << DIRTY_MEMORY_MIGRATION);
     hvmmem_type_t mem_type;
 
     if (section->mr == &ram_memory) {
-- 
2.3.3