From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Date: Wed, 5 Jan 2011 23:14:37 +0000 (+0000)
Subject: qemu-xen: support PV on HVM MSIX remapping
X-Git-Tag: xen-4.1.0-rc1~4
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=7f6daabd70ff94b7465798dcadb71e79562db2b2;p=qemu-xen-4.4-testing.git

qemu-xen: support PV on HVM MSIX remapping

Support PV on HVM MSIX remapping

The technique is the same used with MSI: if the guest enables an MSIX
passing 0 as vector number, then read the address and use it as pirq
number for the following mapping request to Xen.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---

diff --git a/hw/pt-msi.c b/hw/pt-msi.c
index f0fb3e31d..b01744ed5 100644
--- a/hw/pt-msi.c
+++ b/hw/pt-msi.c
@@ -300,6 +300,14 @@ static int pt_msix_update_one(struct pt_dev *dev, int entry_nr)
     if ( !entry->flags )
         return 0;
 
+    if (!gvec) {
+        /* if gvec is 0, the guest is asking for a particular pirq that
+         * is passed as dest_id */
+        pirq = ((gaddr >> 32) & 0xffffff00) |
+               (((gaddr & 0xffffffff) >> MSI_TARGET_CPU_SHIFT) & 0xff);
+        PT_LOG("pt_msix_update_one requested pirq = %d\n", pirq);
+    }
+
     /* Check if this entry is already mapped */
     if ( entry->pirq == -1 )
     {