Merge remote-tracking branch 'mst/tags/for_anthony' into staging

pci,virtio

This further optimizes MSIX handling in virtio-pci.
Also included is pci cleanup by Paolo, and pci device
assignment fix by Alex.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

* mst/tags/for_anthony:
  pci-assign: Enable MSIX on device to match guest
  pci: use constants for devices under the 1B36 device ID, document them
  ivshmem: use symbolic constant for PCI ID, add to pci-ids.txt
  virtio-9p: use symbolic constant, add to pci-ids.txt
  reorganize pci-ids.txt
  docs: move pci-ids.txt to docs/specs/
  vhost: backend masking support
  vhost: set started flag while start is in progress
  virtio-net: set/clear vhost_started in reverse order
  virtio: backend virtqueue notifier masking
  virtio-pci: cache msix messages
  kvm: add stub for update msi route
  msix: add api to access msix message
  virtio: don't waste irqfds on control vqs

1 files changed, 15 insertions, 2 deletions

diff --git a/hw/kvm/pci-assign.c b/hw/kvm/pci-assign.c
index 8ee9428..896cfe8 100644
--- a/hw/kvm/pci-assign.c
+++ b/hw/kvm/pci-assign.c
@@ -1031,6 +1031,19 @@ static bool assigned_dev_msix_masked(MSIXTableEntry *entry)
     return (entry->ctrl & cpu_to_le32(0x1)) != 0;
 }
 
+/*
+ * When MSI-X is first enabled the vector table typically has all the
+ * vectors masked, so we can't use that as the obvious test to figure out
+ * how many vectors to initially enable.  Instead we look at the data field
+ * because this is what worked for pci-assign for a long time.  This makes
+ * sure the physical MSI-X state tracks the guest's view, which is important
+ * for some VF/PF and PF/fw communication channels.
+ */
+static bool assigned_dev_msix_skipped(MSIXTableEntry *entry)
+{
+    return !entry->data;
+}
+
 static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev)
 {
     AssignedDevice *adev = DO_UPCAST(AssignedDevice, dev, pci_dev);
@@ -1041,7 +1054,7 @@ static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev)
 
     /* Get the usable entry number for allocating */
     for (i = 0; i < adev->msix_max; i++, entry++) {
-        if (assigned_dev_msix_masked(entry)) {
+        if (assigned_dev_msix_skipped(entry)) {
             continue;
         }
         entries_nr++;
@@ -1070,7 +1083,7 @@ static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev)
     for (i = 0; i < adev->msix_max; i++, entry++) {
         adev->msi_virq[i] = -1;
 
-        if (assigned_dev_msix_masked(entry)) {
+        if (assigned_dev_msix_skipped(entry)) {
             continue;
         }