Re: [Qemu-devel] [PULL 39/47] pc: memhp: enable nvdimm device hotplug

[Igor Mammedov]

On Sun, 30 Oct 2016 23:25:10 +0200
"Michael S. Tsirkin" <address@hidden> wrote:

> From: Xiao Guangrong <address@hidden>
> 
> _GPE.E04 is dedicated for nvdimm device hotplug
> 
> Signed-off-by: Xiao Guangrong <address@hidden>
> Reviewed-by: Michael S. Tsirkin <address@hidden>
> Signed-off-by: Michael S. Tsirkin <address@hidden>
> ---
>  include/hw/acpi/acpi_dev_interface.h |  1 +
>  hw/acpi/memory_hotplug.c             | 31 +++++++++++++++++++++++--------
>  hw/i386/acpi-build.c                 |  7 +++++++
>  hw/i386/pc.c                         | 12 ++++++++++++
>  hw/mem/nvdimm.c                      |  4 ----
>  docs/specs/acpi_mem_hotplug.txt      |  3 +++
>  6 files changed, 46 insertions(+), 12 deletions(-)
> 
> diff --git a/include/hw/acpi/acpi_dev_interface.h 
> b/include/hw/acpi/acpi_dev_interface.h
> index da4ef7f..901a4ae 100644
> --- a/include/hw/acpi/acpi_dev_interface.h
> +++ b/include/hw/acpi/acpi_dev_interface.h
> @@ -10,6 +10,7 @@ typedef enum {
>      ACPI_PCI_HOTPLUG_STATUS = 2,
>      ACPI_CPU_HOTPLUG_STATUS = 4,
>      ACPI_MEMORY_HOTPLUG_STATUS = 8,
> +    ACPI_NVDIMM_HOTPLUG_STATUS = 16,
>  } AcpiEventStatusBits;
>  
>  #define TYPE_ACPI_DEVICE_IF "acpi-device-interface"
> diff --git a/hw/acpi/memory_hotplug.c b/hw/acpi/memory_hotplug.c
> index ec4e64b..70f6451 100644
> --- a/hw/acpi/memory_hotplug.c
> +++ b/hw/acpi/memory_hotplug.c
> @@ -2,6 +2,7 @@
>  #include "hw/acpi/memory_hotplug.h"
>  #include "hw/acpi/pc-hotplug.h"
>  #include "hw/mem/pc-dimm.h"
> +#include "hw/mem/nvdimm.h"
>  #include "hw/boards.h"
>  #include "hw/qdev-core.h"
>  #include "trace.h"
> @@ -232,11 +233,8 @@ void acpi_memory_plug_cb(HotplugHandler *hotplug_dev, 
> MemHotplugState *mem_st,
>                           DeviceState *dev, Error **errp)
>  {
>      MemStatus *mdev;
> -    DeviceClass *dc = DEVICE_GET_CLASS(dev);
> -
> -    if (!dc->hotpluggable) {
> -        return;
> -    }
shouldn't be removed.

> +    AcpiEventStatusBits event;
> +    bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
>  
>      mdev = acpi_memory_slot_status(mem_st, dev, errp);
>      if (!mdev) {
> @@ -244,10 +242,23 @@ void acpi_memory_plug_cb(HotplugHandler *hotplug_dev, 
> MemHotplugState *mem_st,
>      }
>  
>      mdev->dimm = dev;
> -    mdev->is_enabled = true;
> +
> +    /*
> +     * do not set is_enabled and is_inserting if the slot is plugged with
> +     * a nvdimm device to stop OSPM inquires memory region from the slot.
> +     */
> +    if (is_nvdimm) {
> +        event = ACPI_NVDIMM_HOTPLUG_STATUS;
> +    } else {
> +        mdev->is_enabled = true;
> +        event = ACPI_MEMORY_HOTPLUG_STATUS;
> +    }
> +
>      if (dev->hotplugged) {
> -        mdev->is_inserting = true;
> -        acpi_send_event(DEVICE(hotplug_dev), ACPI_MEMORY_HOTPLUG_STATUS);
> +        if (!is_nvdimm) {
> +            mdev->is_inserting = true;
> +        }
> +        acpi_send_event(DEVICE(hotplug_dev), event);
>      }
>  }
>  
> @@ -262,6 +273,8 @@ void acpi_memory_unplug_request_cb(HotplugHandler 
> *hotplug_dev,
>          return;
>      }
>  
> +    /* nvdimm device hot unplug is not supported yet. */
> +    assert(!object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM));
that would crash guest instead of failing gracefully as it's supposed to.

>      mdev->is_removing = true;
>      acpi_send_event(DEVICE(hotplug_dev), ACPI_MEMORY_HOTPLUG_STATUS);
>  }
> @@ -276,6 +289,8 @@ void acpi_memory_unplug_cb(MemHotplugState *mem_st,
>          return;
>      }
>  
> +    /* nvdimm device hot unplug is not supported yet. */
> +    assert(!object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM));
ditto

>      mdev->is_enabled = false;
>      mdev->dimm = NULL;
>  }
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 03a5386..7aaa07a 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -2069,6 +2069,13 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>          method = aml_method("_E03", 0, AML_NOTSERIALIZED);
>          aml_append(method, aml_call0(MEMORY_HOTPLUG_HANDLER_PATH));
>          aml_append(scope, method);
> +
> +        if (pcms->acpi_nvdimm_state.is_enabled) {
> +            method = aml_method("_E04", 0, AML_NOTSERIALIZED);
> +            aml_append(method, aml_notify(aml_name("\\_SB.NVDR"),
> +                                          aml_int(0x80)));
> +            aml_append(scope, method);
> +        }
>      }
>      aml_append(dsdt, scope);
>  
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index b395717..c011552 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1744,6 +1744,12 @@ static void pc_dimm_unplug_request(HotplugHandler 
> *hotplug_dev,
>          goto out;
>      }
>  
> +    if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> +        error_setg(&local_err,
> +                   "nvdimm device hot unplug is not supported yet.");
> +        goto out;
> +    }
> +
>      hhc = HOTPLUG_HANDLER_GET_CLASS(pcms->acpi_dev);
>      hhc->unplug_request(HOTPLUG_HANDLER(pcms->acpi_dev), dev, &local_err);
>  
> @@ -1761,6 +1767,12 @@ static void pc_dimm_unplug(HotplugHandler *hotplug_dev,
>      HotplugHandlerClass *hhc;
>      Error *local_err = NULL;
>  
> +    if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> +        error_setg(&local_err,
> +                   "nvdimm device hot unplug is not supported yet.");
> +        goto out;
> +    }
> +
>      hhc = HOTPLUG_HANDLER_GET_CLASS(pcms->acpi_dev);
>      hhc->unplug(HOTPLUG_HANDLER(pcms->acpi_dev), dev, &local_err);
>  
> diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c
> index 7895805..db896b0 100644
> --- a/hw/mem/nvdimm.c
> +++ b/hw/mem/nvdimm.c
> @@ -148,13 +148,9 @@ static MemoryRegion 
> *nvdimm_get_vmstate_memory_region(PCDIMMDevice *dimm)
>  
>  static void nvdimm_class_init(ObjectClass *oc, void *data)
>  {
> -    DeviceClass *dc = DEVICE_CLASS(oc);
>      PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
>      NVDIMMClass *nvc = NVDIMM_CLASS(oc);
>  
> -    /* nvdimm hotplug has not been supported yet. */
> -    dc->hotpluggable = false;
> -
>      ddc->realize = nvdimm_realize;
>      ddc->get_memory_region = nvdimm_get_memory_region;
>      ddc->get_vmstate_memory_region = nvdimm_get_vmstate_memory_region;
> diff --git a/docs/specs/acpi_mem_hotplug.txt b/docs/specs/acpi_mem_hotplug.txt
> index 3df3620..cb26dd2 100644
> --- a/docs/specs/acpi_mem_hotplug.txt
> +++ b/docs/specs/acpi_mem_hotplug.txt
> @@ -4,6 +4,9 @@ QEMU<->ACPI BIOS memory hotplug interface
>  ACPI BIOS GPE.3 handler is dedicated for notifying OS about memory hot-add
>  and hot-remove events.
>  
> +ACPI BIOS GPE.4 handler is dedicated for notifying OS about nvdimm device
> +hot-add and hot-remove events.
> +
>  Memory hot-plug interface (IO port 0xa00-0xa17, 1-4 byte access):
>  ---------------------------------------------------------------
>  0xa00: