[PATCHv2,4/7] spapr_pci: Allow EEH on spapr-pci-host-bridge

Commit Message

David Gibson Feb. 29, 2016, 7:06 a.m. UTC

Now that the EEH code is independent of the special
spapr-vfio-pci-host-bridge device, we can allow it on all spapr PCI
host bridges instead.  We do this by changing spapr_phb_eeh_available()
to be based on the vfio_eeh_as_ok() call instead of the host bridge class.

Because the value of vfio_eeh_as_ok() can change with devices being
hotplugged or unplugged, this can potentially lead to some strange edge
cases where the guest starts using EEH, then it starts failing because
of a change in status.

However, it's not really any worse than the current situation.  Cases that
would have worked previously will still work (i.e. VFIO devices from at
most one VFIO IOMMU group per vPHB), it's just that it's no longer
necessary to use spapr-vfio-pci-host-bridge with the groupid pre-specified.

Signed-off-by: David Gibson <[e-mail]>
---
 hw/ppc/spapr_pci.c          | 10 ++--------
 hw/ppc/spapr_pci_vfio.c     |  6 +++++-
 include/hw/pci-host/spapr.h |  6 +++++-
 3 files changed, 12 insertions(+), 10 deletions(-)

Comments

Alexey Kardashevskiy Feb. 29, 2016, 7:28 a.m. UTC | #1

On 02/29/2016 06:06 PM, David Gibson wrote:
> Now that the EEH code is independent of the special
> spapr-vfio-pci-host-bridge device, we can allow it on all spapr PCI
> host bridges instead.  We do this by changing spapr_phb_eeh_available()
> to be based on the vfio_eeh_as_ok() call instead of the host bridge class.
>
> Because the value of vfio_eeh_as_ok() can change with devices being
> hotplugged or unplugged, this can potentially lead to some strange edge
> cases where the guest starts using EEH, then it starts failing because
> of a change in status.
>
> However, it's not really any worse than the current situation.  Cases that
> would have worked previously will still work (i.e. VFIO devices from at
> most one VFIO IOMMU group per vPHB), it's just that it's no longer
> necessary to use spapr-vfio-pci-host-bridge with the groupid pre-specified.
>
> Signed-off-by: David Gibson <[e-mail]>

Reviewed-by: Alexey Kardashevskiy <[e-mail]>

Patch

diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index be05757..4ac5273 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -42,6 +42,8 @@ 
 #include "hw/ppc/spapr_drc.h"
 #include "sysemu/device_tree.h"
 
+#include "hw/vfio/vfio.h"
+
 /* Copied from the kernel arch/powerpc/platforms/pseries/msi.c */
 #define RTAS_QUERY_FN           0
 #define RTAS_CHANGE_FN          1
@@ -92,13 +94,6 @@  PCIDevice *spapr_pci_find_dev(sPAPRMachineState *spapr, uint64_t buid,
     return pci_find_device(phb->bus, bus_num, devfn);
 }
 
-static bool spapr_phb_eeh_available(sPAPRPHBState *sphb)
-{
-    sPAPRPHBClass *spc = SPAPR_PCI_HOST_BRIDGE_GET_CLASS(sphb);
-
-    return spc->eeh_available;
-}
-
 static uint32_t rtas_pci_cfgaddr(uint32_t arg)
 {
     /* This handles the encoding of extended config space addresses */
@@ -1563,7 +1558,6 @@  static void spapr_phb_class_init(ObjectClass *klass, void *data)
     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
     dc->cannot_instantiate_with_device_add_yet = false;
     spc->finish_realize = spapr_phb_finish_realize;
-    spc->eeh_available = false;
     hp->plug = spapr_phb_hot_plug_child;
     hp->unplug = spapr_phb_hot_unplug_child;
 }
diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
index 10fa88a..16a4a8f 100644
--- a/hw/ppc/spapr_pci_vfio.c
+++ b/hw/ppc/spapr_pci_vfio.c
@@ -73,6 +73,11 @@  static void spapr_phb_vfio_finish_realize(sPAPRPHBState *sphb, Error **errp)
                                 spapr_tce_get_iommu(tcet));
 }
 
+bool spapr_phb_eeh_available(sPAPRPHBState *sphb)
+{
+    return vfio_eeh_as_ok(&sphb->iommu_as);
+}
+
 static void spapr_phb_vfio_eeh_reenable(sPAPRPHBState *sphb)
 {
     vfio_eeh_as_op(&sphb->iommu_as, VFIO_EEH_PE_ENABLE);
@@ -240,7 +245,6 @@  static void spapr_phb_vfio_class_init(ObjectClass *klass, void *data)
 
     dc->props = spapr_phb_vfio_properties;
     spc->finish_realize = spapr_phb_vfio_finish_realize;
-    spc->eeh_available = true;
 }
 
 static const TypeInfo spapr_phb_vfio_info = {
diff --git a/include/hw/pci-host/spapr.h b/include/hw/pci-host/spapr.h
index 0b936c6..19a95e0 100644
--- a/include/hw/pci-host/spapr.h
+++ b/include/hw/pci-host/spapr.h
@@ -49,7 +49,6 @@  struct sPAPRPHBClass {
     PCIHostBridgeClass parent_class;
 
     void (*finish_realize)(sPAPRPHBState *sphb, Error **errp);
-    bool eeh_available;
 };
 
 typedef struct spapr_pci_msi {
@@ -136,6 +135,7 @@  PCIDevice *spapr_pci_find_dev(sPAPRMachineState *spapr, uint64_t buid,
 
 /* VFIO EEH hooks */
 #ifdef CONFIG_LINUX
+bool spapr_phb_eeh_available(sPAPRPHBState *sphb);
 int spapr_phb_vfio_eeh_set_option(sPAPRPHBState *sphb,
                                   unsigned int addr, int option);
 int spapr_phb_vfio_eeh_get_state(sPAPRPHBState *sphb, int *state);
@@ -143,6 +143,10 @@  int spapr_phb_vfio_eeh_reset(sPAPRPHBState *sphb, int option);
 int spapr_phb_vfio_eeh_configure(sPAPRPHBState *sphb);
 void spapr_phb_vfio_reset(DeviceState *qdev);
 #else
+static inline bool spapr_phb_eeh_available(sPAPRPHBState *sphb)
+{
+    return false;
+}
 static inline int spapr_phb_vfio_eeh_set_option(sPAPRPHBState *sphb,
                                                 unsigned int addr, int option)
 {