Linux Virtualization - Aug 2009 - [PATCHv3 2/4] virtio: move features to an inline function

devices should have the final say over which virtio features they
support. E.g. indirect entries may or may not make sense in the context
of virtio-console.  Move the common bits from virtio-pci to an inline
function and let each device call it.

No functional changes.

Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
 hw/virtio-balloon.c |    2 +-
 hw/virtio-blk.c     |    2 +-
 hw/virtio-console.c |    2 +-
 hw/virtio-net.c     |    2 +-
 hw/virtio-pci.c     |    3 ---
 hw/virtio.h         |   10 ++++++++++
 6 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/hw/virtio-balloon.c b/hw/virtio-balloon.c
index 7ca783e..15b50bb 100644
--- a/hw/virtio-balloon.c
+++ b/hw/virtio-balloon.c
@@ -127,7 +127,7 @@ static void virtio_balloon_set_config(VirtIODevice *vdev,
 
 static uint32_t virtio_balloon_get_features(VirtIODevice *vdev)
 {
-    return 0;
+    return virtio_common_features();
 }
 
 static ram_addr_t virtio_balloon_to_target(void *opaque, ram_addr_t target)
diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c
index c278d2e..a33eafb 100644
--- a/hw/virtio-blk.c
+++ b/hw/virtio-blk.c
@@ -378,7 +378,7 @@ static uint32_t virtio_blk_get_features(VirtIODevice *vdev)
     if (strcmp(s->serial_str, "0"))
         features |= 1 << VIRTIO_BLK_F_IDENTIFY;
 
-    return features;
+    return features | virtio_common_features();
 }
 
 static void virtio_blk_save(QEMUFile *f, void *opaque)
diff --git a/hw/virtio-console.c b/hw/virtio-console.c
index 663c8b9..ac25499 100644
--- a/hw/virtio-console.c
+++ b/hw/virtio-console.c
@@ -53,7 +53,7 @@ static void virtio_console_handle_input(VirtIODevice *vdev,
VirtQueue *vq)
 
 static uint32_t virtio_console_get_features(VirtIODevice *vdev)
 {
-    return 0;
+    return virtio_common_features();
 }
 
 static int vcon_can_read(void *opaque)
diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index ce8e6cb..469c6e3 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -154,7 +154,7 @@ static uint32_t virtio_net_get_features(VirtIODevice *vdev)
     }
 #endif
 
-    return features;
+    return features | virtio_common_features();
 }
 
 static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index 8b57dfc..ab6e9c4 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -230,9 +230,6 @@ static uint32_t virtio_ioport_read(VirtIOPCIProxy *proxy,
uint32_t addr)
     switch (addr) {
     case VIRTIO_PCI_HOST_FEATURES:
         ret = vdev->get_features(vdev);
-        ret |= (1 << VIRTIO_F_NOTIFY_ON_EMPTY);
-        ret |= (1 << VIRTIO_RING_F_INDIRECT_DESC);
-        ret |= (1 << VIRTIO_F_BAD_FEATURE);
         break;
     case VIRTIO_PCI_GUEST_FEATURES:
         ret = vdev->features;
diff --git a/hw/virtio.h b/hw/virtio.h
index c441a93..cbf472b 100644
--- a/hw/virtio.h
+++ b/hw/virtio.h
@@ -167,4 +167,14 @@ VirtIODevice *virtio_net_init(DeviceState *dev);
 VirtIODevice *virtio_console_init(DeviceState *dev);
 VirtIODevice *virtio_balloon_init(DeviceState *dev);
 
+static inline uint32_t virtio_common_features(void)
+{
+    uint32_t features = 0;
+    features |= (1 << VIRTIO_F_NOTIFY_ON_EMPTY);
+    features |= (1 << VIRTIO_RING_F_INDIRECT_DESC);
+    features |= (1 << VIRTIO_F_BAD_FEATURE);
+
+    return features;
+}
+
 #endif
-- 
1.6.2.5