[for-6.0,7/9] spapr: Do PHB hoplug sanity check at pre-plug

Commit Message

Greg Kurz Nov. 20, 2020, 11:42 p.m. UTC

We currently detect that a PHB index is already in use at plug time.
But this can be decteted at pre-plug in order to error out earlier.

This allows to pass &error_abort to spapr_drc_attach() and to end
up with a plug handler that doesn't need to report errors anymore.

Signed-off-by: Greg Kurz <[e-mail]>
---
 hw/ppc/spapr.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

Comments

David Gibson Nov. 23, 2020, 5:26 a.m. UTC | #1

On Sat, Nov 21, 2020 at 12:42:06AM +0100, Greg Kurz wrote:
> We currently detect that a PHB index is already in use at plug time.
> But this can be decteted at pre-plug in order to error out earlier.
> 
> This allows to pass &error_abort to spapr_drc_attach() and to end
> up with a plug handler that doesn't need to report errors anymore.
> 
> Signed-off-by: Greg Kurz <[e-mail]>

Applied to ppc-for-6.0, thanks.

> ---
>  hw/ppc/spapr.c | 17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index 81bac59887ab..bded059d59c8 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -3872,6 +3872,7 @@ static bool spapr_phb_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>      SpaprPhbState *sphb = SPAPR_PCI_HOST_BRIDGE(dev);
>      SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
>      const unsigned windows_supported = spapr_phb_windows_supported(sphb);
> +    SpaprDrc *drc;
>  
>      if (dev->hotplugged && !smc->dr_phb_enabled) {
>          error_setg(errp, "PHB hotplug not supported for this machine");
> @@ -3883,6 +3884,12 @@ static bool spapr_phb_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>          return false;
>      }
>  
> +    drc = spapr_drc_by_id(TYPE_SPAPR_DRC_PHB, sphb->index);
> +    if (drc && drc->dev) {
> +        error_setg(errp, "PHB %d already attached", sphb->index);
> +        return false;
> +    }
> +
>      /*
>       * This will check that sphb->index doesn't exceed the maximum number of
>       * PHBs for the current machine type.
> @@ -3896,8 +3903,7 @@ static bool spapr_phb_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>                             errp);
>  }
>  
> -static void spapr_phb_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
> -                           Error **errp)
> +static void spapr_phb_plug(HotplugHandler *hotplug_dev, DeviceState *dev)
>  {
>      SpaprMachineState *spapr = SPAPR_MACHINE(OBJECT(hotplug_dev));
>      SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
> @@ -3913,9 +3919,8 @@ static void spapr_phb_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>      /* hotplug hooks should check it's enabled before getting this far */
>      assert(drc);
>  
> -    if (!spapr_drc_attach(drc, dev, errp)) {
> -        return;
> -    }
> +    /* spapr_phb_pre_plug() already checked the DRC is attachable */
> +    spapr_drc_attach(drc, dev, &error_abort);
>  
>      if (hotplugged) {
>          spapr_hotplug_req_add_by_index(drc);
> @@ -3983,7 +3988,7 @@ static void spapr_machine_device_plug(HotplugHandler *hotplug_dev,
>      } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE)) {
>          spapr_core_plug(hotplug_dev, dev);
>      } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_PCI_HOST_BRIDGE)) {
> -        spapr_phb_plug(hotplug_dev, dev, errp);
> +        spapr_phb_plug(hotplug_dev, dev);
>      } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_TPM_PROXY)) {
>          spapr_tpm_proxy_plug(hotplug_dev, dev, errp);
>      }

Patch

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 81bac59887ab..bded059d59c8 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3872,6 +3872,7 @@  static bool spapr_phb_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     SpaprPhbState *sphb = SPAPR_PCI_HOST_BRIDGE(dev);
     SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
     const unsigned windows_supported = spapr_phb_windows_supported(sphb);
+    SpaprDrc *drc;
 
     if (dev->hotplugged && !smc->dr_phb_enabled) {
         error_setg(errp, "PHB hotplug not supported for this machine");
@@ -3883,6 +3884,12 @@  static bool spapr_phb_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
         return false;
     }
 
+    drc = spapr_drc_by_id(TYPE_SPAPR_DRC_PHB, sphb->index);
+    if (drc && drc->dev) {
+        error_setg(errp, "PHB %d already attached", sphb->index);
+        return false;
+    }
+
     /*
      * This will check that sphb->index doesn't exceed the maximum number of
      * PHBs for the current machine type.
@@ -3896,8 +3903,7 @@  static bool spapr_phb_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
                            errp);
 }
 
-static void spapr_phb_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
-                           Error **errp)
+static void spapr_phb_plug(HotplugHandler *hotplug_dev, DeviceState *dev)
 {
     SpaprMachineState *spapr = SPAPR_MACHINE(OBJECT(hotplug_dev));
     SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(spapr);
@@ -3913,9 +3919,8 @@  static void spapr_phb_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     /* hotplug hooks should check it's enabled before getting this far */
     assert(drc);
 
-    if (!spapr_drc_attach(drc, dev, errp)) {
-        return;
-    }
+    /* spapr_phb_pre_plug() already checked the DRC is attachable */
+    spapr_drc_attach(drc, dev, &error_abort);
 
     if (hotplugged) {
         spapr_hotplug_req_add_by_index(drc);
@@ -3983,7 +3988,7 @@  static void spapr_machine_device_plug(HotplugHandler *hotplug_dev,
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_CPU_CORE)) {
         spapr_core_plug(hotplug_dev, dev);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_PCI_HOST_BRIDGE)) {
-        spapr_phb_plug(hotplug_dev, dev, errp);
+        spapr_phb_plug(hotplug_dev, dev);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_SPAPR_TPM_PROXY)) {
         spapr_tpm_proxy_plug(hotplug_dev, dev, errp);
     }