[libvirt] [PATCH 1/2] qemu: add host-pci-multidomain capability

Laine Stump laine at laine.org
Wed Apr 30 13:04:00 UTC 2014


Quite a long time ago, (apparently between qemu 0.12 and 0.13) qemu
quietly began supporting the optional specification of a domain in the
host-side address of all pci passthrough commands (by simply
prepending it to the bus:slot.function format, as
"dddd:bb:ss.f"). Since machines with multiple PCI domains are very
rare, this never came up in practice, so libvirt was never updated to
support it.

This patch takes the first step to supporting specification of a non-0
domain in the host-side address of PCI devices being assigned to a
domain, by adding a capability bit to indicate support
"QEMU_CAPS_HOST_PCI_MULTIDOMAIN", and detect it. Since this support
was added in a version prior to the minimum version required for
QMP-style capabilities detection, the capability is always enabled for
any qemu that uses QMP for capabilities detection. For older qemus,
the only clue that a domain can be specified in the host pci address
is the presence of the string "[seg:]" in the help string for
-pcidevice. (Ironically, libvirt will not be modified to support
specification of domain for -pcidevice, since any qemu new enough for
us to care about also supports "-device pci-assign" or "-device
vfio-pci", which are greatly preferred).
---
 src/qemu/qemu_capabilities.c                  | 4 ++++
 src/qemu/qemu_capabilities.h                  | 1 +
 tests/qemucapabilitiesdata/caps_1.2.2-1.caps  | 1 +
 tests/qemucapabilitiesdata/caps_1.3.1-1.caps  | 1 +
 tests/qemucapabilitiesdata/caps_1.4.2-1.caps  | 1 +
 tests/qemucapabilitiesdata/caps_1.5.3-1.caps  | 1 +
 tests/qemucapabilitiesdata/caps_1.6.0-1.caps  | 1 +
 tests/qemucapabilitiesdata/caps_1.6.50-1.caps | 1 +
 tests/qemuhelptest.c                          | 3 ++-
 9 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index b491f58..238cccc 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -254,6 +254,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
               "spiceport",
 
               "usb-kbd", /* 165 */
+              "host-pci-multidomain",
     );
 
 
@@ -1043,6 +1044,8 @@ virQEMUCapsComputeCmdFlags(const char *help,
         virQEMUCapsSet(qemuCaps, QEMU_CAPS_DRIVE_SERIAL);
     if (strstr(help, "-pcidevice"))
         virQEMUCapsSet(qemuCaps, QEMU_CAPS_PCIDEVICE);
+    if (strstr(help, "[seg:]bus"))
+        virQEMUCapsSet(qemuCaps, QEMU_CAPS_HOST_PCI_MULTIDOMAIN);
     if (strstr(help, "-mem-path"))
         virQEMUCapsSet(qemuCaps, QEMU_CAPS_MEM_PATH);
     if (strstr(help, "-chardev")) {
@@ -2970,6 +2973,7 @@ virQEMUCapsInitQMPBasic(virQEMUCapsPtr qemuCaps)
     virQEMUCapsSet(qemuCaps, QEMU_CAPS_MACHINE_OPT);
     virQEMUCapsSet(qemuCaps, QEMU_CAPS_DUMP_GUEST_CORE);
     virQEMUCapsSet(qemuCaps, QEMU_CAPS_VNC_SHARE_POLICY);
+    virQEMUCapsSet(qemuCaps, QEMU_CAPS_HOST_PCI_MULTIDOMAIN);
 }
 
 /* Capabilities that are architecture depending
diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
index 5c63b81..26400d2 100644
--- a/src/qemu/qemu_capabilities.h
+++ b/src/qemu/qemu_capabilities.h
@@ -204,6 +204,7 @@ enum virQEMUCapsFlags {
     QEMU_CAPS_SPICE_FILE_XFER_DISABLE = 163, /* -spice disable-agent-file-xfer */
     QEMU_CAPS_CHARDEV_SPICEPORT  = 164, /* -chardev spiceport */
     QEMU_CAPS_DEVICE_USB_KBD     = 165, /* -device usb-kbd */
+    QEMU_CAPS_HOST_PCI_MULTIDOMAIN = 166, /* support domain > 0 in host pci address */
 
     QEMU_CAPS_LAST,                   /* this must always be the last item */
 };
diff --git a/tests/qemucapabilitiesdata/caps_1.2.2-1.caps b/tests/qemucapabilitiesdata/caps_1.2.2-1.caps
index 436cecd..ebbfb82 100644
--- a/tests/qemucapabilitiesdata/caps_1.2.2-1.caps
+++ b/tests/qemucapabilitiesdata/caps_1.2.2-1.caps
@@ -114,4 +114,5 @@
     <flag name='kvm-pit-lost-tick-policy'/>
     <flag name='enable-fips'/>
     <flag name='usb-kbd'/>
+    <flag name='host-pci-multidomain'/>
   </qemuCaps>
diff --git a/tests/qemucapabilitiesdata/caps_1.3.1-1.caps b/tests/qemucapabilitiesdata/caps_1.3.1-1.caps
index 6b4a8f0..ab631a2 100644
--- a/tests/qemucapabilitiesdata/caps_1.3.1-1.caps
+++ b/tests/qemucapabilitiesdata/caps_1.3.1-1.caps
@@ -127,4 +127,5 @@
     <flag name='usb-storage.removable'/>
     <flag name='kvm-pit-lost-tick-policy'/>
     <flag name='usb-kbd'/>
+    <flag name='host-pci-multidomain'/>
   </qemuCaps>
diff --git a/tests/qemucapabilitiesdata/caps_1.4.2-1.caps b/tests/qemucapabilitiesdata/caps_1.4.2-1.caps
index e3d0047..e710b60 100644
--- a/tests/qemucapabilitiesdata/caps_1.4.2-1.caps
+++ b/tests/qemucapabilitiesdata/caps_1.4.2-1.caps
@@ -128,4 +128,5 @@
     <flag name='ich9-intel-hda'/>
     <flag name='kvm-pit-lost-tick-policy'/>
     <flag name='usb-kbd'/>
+    <flag name='host-pci-multidomain'/>
   </qemuCaps>
diff --git a/tests/qemucapabilitiesdata/caps_1.5.3-1.caps b/tests/qemucapabilitiesdata/caps_1.5.3-1.caps
index 01b4d27..36758c8 100644
--- a/tests/qemucapabilitiesdata/caps_1.5.3-1.caps
+++ b/tests/qemucapabilitiesdata/caps_1.5.3-1.caps
@@ -136,4 +136,5 @@
     <flag name='reboot-timeout'/>
     <flag name='spiceport'/>
     <flag name='usb-kbd'/>
+    <flag name='host-pci-multidomain'/>
   </qemuCaps>
diff --git a/tests/qemucapabilitiesdata/caps_1.6.0-1.caps b/tests/qemucapabilitiesdata/caps_1.6.0-1.caps
index 597f873..7b86c3b 100644
--- a/tests/qemucapabilitiesdata/caps_1.6.0-1.caps
+++ b/tests/qemucapabilitiesdata/caps_1.6.0-1.caps
@@ -142,4 +142,5 @@
     <flag name='spice-file-xfer-disable'/>
     <flag name='spiceport'/>
     <flag name='usb-kbd'/>
+    <flag name='host-pci-multidomain'/>
   </qemuCaps>
diff --git a/tests/qemucapabilitiesdata/caps_1.6.50-1.caps b/tests/qemucapabilitiesdata/caps_1.6.50-1.caps
index 0c1dd87..10b8251 100644
--- a/tests/qemucapabilitiesdata/caps_1.6.50-1.caps
+++ b/tests/qemucapabilitiesdata/caps_1.6.50-1.caps
@@ -140,4 +140,5 @@
     <flag name='spice-file-xfer-disable'/>
     <flag name='spiceport'/>
     <flag name='usb-kbd'/>
+    <flag name='host-pci-multidomain'/>
   </qemuCaps>
diff --git a/tests/qemuhelptest.c b/tests/qemuhelptest.c
index 6eb8096..105a563 100644
--- a/tests/qemuhelptest.c
+++ b/tests/qemuhelptest.c
@@ -517,7 +517,8 @@ mymain(void)
             QEMU_CAPS_DEVICE_PCI_BRIDGE,
             QEMU_CAPS_DEVICE_SCSI_GENERIC,
             QEMU_CAPS_DEVICE_USB_KBD,
-            QEMU_CAPS_DEVICE_USB_STORAGE);
+            QEMU_CAPS_DEVICE_USB_STORAGE,
+            QEMU_CAPS_HOST_PCI_MULTIDOMAIN);
     DO_TEST("qemu-kvm-0.12.1.2-rhel61", 12001, 1, 0,
             QEMU_CAPS_VNC_COLON,
             QEMU_CAPS_NO_REBOOT,
-- 
1.9.0




More information about the libvir-list mailing list