diff mbox

[v2,07/18] nvdimm: reserve address range for NVDIMM

Message ID 1439563931-12352-8-git-send-email-guangrong.xiao@linux.intel.com
State New, archived
Headers show

Commit Message

Xiao Guangrong Aug. 14, 2015, 2:52 p.m. UTC
NVDIMM reserves all the free range above 4G to do:
- Persistent Memory (PMEM) mapping
- implement NVDIMM ACPI device _DSM method

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
---
 hw/i386/pc.c               | 12 ++++++++++--
 hw/mem/nvdimm/pc-nvdimm.c  | 13 +++++++++++++
 include/hw/mem/pc-nvdimm.h |  1 +
 3 files changed, 24 insertions(+), 2 deletions(-)

Comments

Stefan Hajnoczi Aug. 25, 2015, 3:12 p.m. UTC | #1
On Fri, Aug 14, 2015 at 10:52:00PM +0800, Xiao Guangrong wrote:
> diff --git a/hw/mem/nvdimm/pc-nvdimm.c b/hw/mem/nvdimm/pc-nvdimm.c
> index a53d235..7a270a8 100644
> --- a/hw/mem/nvdimm/pc-nvdimm.c
> +++ b/hw/mem/nvdimm/pc-nvdimm.c
> @@ -24,6 +24,19 @@
>  
>  #include "hw/mem/pc-nvdimm.h"
>  
> +#define PAGE_SIZE      (1UL << 12)

This macro name is likely to collide with system headers or other code.

Could you use the existing TARGET_PAGE_SIZE constant instead?
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Stefan Hajnoczi Aug. 25, 2015, 3:39 p.m. UTC | #2
On Fri, Aug 14, 2015 at 10:52:00PM +0800, Xiao Guangrong wrote:
> NVDIMM reserves all the free range above 4G to do:
> - Persistent Memory (PMEM) mapping
> - implement NVDIMM ACPI device _DSM method
> 
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> ---
>  hw/i386/pc.c               | 12 ++++++++++--
>  hw/mem/nvdimm/pc-nvdimm.c  | 13 +++++++++++++
>  include/hw/mem/pc-nvdimm.h |  1 +
>  3 files changed, 24 insertions(+), 2 deletions(-)

CCing Igor for memory hotplug-related changes.

> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 7661ea9..41af6ea 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -64,6 +64,7 @@
>  #include "hw/pci/pci_host.h"
>  #include "acpi-build.h"
>  #include "hw/mem/pc-dimm.h"
> +#include "hw/mem/pc-nvdimm.h"
>  #include "qapi/visitor.h"
>  #include "qapi-visit.h"
>  
> @@ -1302,6 +1303,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>      MemoryRegion *ram_below_4g, *ram_above_4g;
>      FWCfgState *fw_cfg;
>      PCMachineState *pcms = PC_MACHINE(machine);
> +    ram_addr_t offset;
>  
>      assert(machine->ram_size == below_4g_mem_size + above_4g_mem_size);
>  
> @@ -1339,6 +1341,8 @@ FWCfgState *pc_memory_init(MachineState *machine,
>          exit(EXIT_FAILURE);
>      }
>  
> +    offset = 0x100000000ULL + above_4g_mem_size;
> +
>      /* initialize hotplug memory address space */
>      if (guest_info->has_reserved_memory &&
>          (machine->ram_size < machine->maxram_size)) {
> @@ -1358,8 +1362,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>              exit(EXIT_FAILURE);
>          }
>  
> -        pcms->hotplug_memory.base =
> -            ROUND_UP(0x100000000ULL + above_4g_mem_size, 1ULL << 30);
> +        pcms->hotplug_memory.base = ROUND_UP(offset, 1ULL << 30);
>  
>          if (pcms->enforce_aligned_dimm) {
>              /* size hotplug region assuming 1G page max alignment per slot */
> @@ -1377,8 +1380,13 @@ FWCfgState *pc_memory_init(MachineState *machine,
>                             "hotplug-memory", hotplug_mem_size);
>          memory_region_add_subregion(system_memory, pcms->hotplug_memory.base,
>                                      &pcms->hotplug_memory.mr);
> +
> +        offset = pcms->hotplug_memory.base + hotplug_mem_size;
>      }
>  
> +     /* all the space left above 4G is reserved for NVDIMM. */
> +    pc_nvdimm_reserve_range(offset);
> +
>      /* Initialize PC system firmware */
>      pc_system_firmware_init(rom_memory, guest_info->isapc_ram_fw);
>  
> diff --git a/hw/mem/nvdimm/pc-nvdimm.c b/hw/mem/nvdimm/pc-nvdimm.c
> index a53d235..7a270a8 100644
> --- a/hw/mem/nvdimm/pc-nvdimm.c
> +++ b/hw/mem/nvdimm/pc-nvdimm.c
> @@ -24,6 +24,19 @@
>  
>  #include "hw/mem/pc-nvdimm.h"
>  
> +#define PAGE_SIZE      (1UL << 12)
> +
> +static struct nvdimms_info {
> +    ram_addr_t current_addr;
> +} nvdimms_info;
> +
> +/* the address range [offset, ~0ULL) is reserved for NVDIMM. */
> +void pc_nvdimm_reserve_range(ram_addr_t offset)
> +{
> +    offset = ROUND_UP(offset, PAGE_SIZE);
> +    nvdimms_info.current_addr = offset;
> +}
> +
>  static char *get_file(Object *obj, Error **errp)
>  {
>      PCNVDIMMDevice *nvdimm = PC_NVDIMM(obj);
> diff --git a/include/hw/mem/pc-nvdimm.h b/include/hw/mem/pc-nvdimm.h
> index 51152b8..8601e9b 100644
> --- a/include/hw/mem/pc-nvdimm.h
> +++ b/include/hw/mem/pc-nvdimm.h
> @@ -28,4 +28,5 @@ typedef struct PCNVDIMMDevice {
>  #define PC_NVDIMM(obj) \
>      OBJECT_CHECK(PCNVDIMMDevice, (obj), TYPE_PC_NVDIMM)
>  
> +void pc_nvdimm_reserve_range(ram_addr_t offset);
>  #endif
> -- 
> 2.4.3
> 
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Xiao Guangrong Aug. 26, 2015, 9:40 a.m. UTC | #3
On 08/25/2015 11:12 PM, Stefan Hajnoczi wrote:
> On Fri, Aug 14, 2015 at 10:52:00PM +0800, Xiao Guangrong wrote:
>> diff --git a/hw/mem/nvdimm/pc-nvdimm.c b/hw/mem/nvdimm/pc-nvdimm.c
>> index a53d235..7a270a8 100644
>> --- a/hw/mem/nvdimm/pc-nvdimm.c
>> +++ b/hw/mem/nvdimm/pc-nvdimm.c
>> @@ -24,6 +24,19 @@
>>
>>   #include "hw/mem/pc-nvdimm.h"
>>
>> +#define PAGE_SIZE      (1UL << 12)
>
> This macro name is likely to collide with system headers or other code.
>
> Could you use the existing TARGET_PAGE_SIZE constant instead?
>

Will follow your way in the next version. Thank you for pointing it out.
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Eduardo Habkost Aug. 28, 2015, 5:25 p.m. UTC | #4
On Fri, Aug 14, 2015 at 10:52:00PM +0800, Xiao Guangrong wrote:
> NVDIMM reserves all the free range above 4G to do:
> - Persistent Memory (PMEM) mapping
> - implement NVDIMM ACPI device _DSM method
> 
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
[...]
> @@ -1302,6 +1303,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>      MemoryRegion *ram_below_4g, *ram_above_4g;
>      FWCfgState *fw_cfg;
>      PCMachineState *pcms = PC_MACHINE(machine);
> +    ram_addr_t offset;

"offset" is a very generic name. I suggest naming it "nvdimm_offset".

>  
>      assert(machine->ram_size == below_4g_mem_size + above_4g_mem_size);
>  
> @@ -1339,6 +1341,8 @@ FWCfgState *pc_memory_init(MachineState *machine,
>          exit(EXIT_FAILURE);
>      }
>  
> +    offset = 0x100000000ULL + above_4g_mem_size;
> +
>      /* initialize hotplug memory address space */
>      if (guest_info->has_reserved_memory &&
>          (machine->ram_size < machine->maxram_size)) {
> @@ -1358,8 +1362,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>              exit(EXIT_FAILURE);
>          }
>  
> -        pcms->hotplug_memory.base =
> -            ROUND_UP(0x100000000ULL + above_4g_mem_size, 1ULL << 30);
> +        pcms->hotplug_memory.base = ROUND_UP(offset, 1ULL << 30);
>  
>          if (pcms->enforce_aligned_dimm) {
>              /* size hotplug region assuming 1G page max alignment per slot */
Xiao Guangrong Aug. 31, 2015, 7:01 a.m. UTC | #5
Hi Eduardo,

Thank you for reviewing my patches.

On 08/29/2015 01:25 AM, Eduardo Habkost wrote:
> On Fri, Aug 14, 2015 at 10:52:00PM +0800, Xiao Guangrong wrote:
>> NVDIMM reserves all the free range above 4G to do:
>> - Persistent Memory (PMEM) mapping
>> - implement NVDIMM ACPI device _DSM method
>>
>> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> [...]
>> @@ -1302,6 +1303,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>>       MemoryRegion *ram_below_4g, *ram_above_4g;
>>       FWCfgState *fw_cfg;
>>       PCMachineState *pcms = PC_MACHINE(machine);
>> +    ram_addr_t offset;
>
> "offset" is a very generic name. I suggest naming it "nvdimm_offset".

'offset' is used for generic proposal as it is not only used for nvdimm but
also for calculating hotplug_mem_base:
       pcms->hotplug_memory.base = ROUND_UP(offset, 1ULL << 30);

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Igor Mammedov Sept. 4, 2015, 12:02 p.m. UTC | #6
On Fri, 14 Aug 2015 22:52:00 +0800
Xiao Guangrong <guangrong.xiao@linux.intel.com> wrote:

> NVDIMM reserves all the free range above 4G to do:
> - Persistent Memory (PMEM) mapping
> - implement NVDIMM ACPI device _DSM method
> 
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> ---
>  hw/i386/pc.c               | 12 ++++++++++--
>  hw/mem/nvdimm/pc-nvdimm.c  | 13 +++++++++++++
>  include/hw/mem/pc-nvdimm.h |  1 +
>  3 files changed, 24 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 7661ea9..41af6ea 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -64,6 +64,7 @@
>  #include "hw/pci/pci_host.h"
>  #include "acpi-build.h"
>  #include "hw/mem/pc-dimm.h"
> +#include "hw/mem/pc-nvdimm.h"
>  #include "qapi/visitor.h"
>  #include "qapi-visit.h"
>  
> @@ -1302,6 +1303,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>      MemoryRegion *ram_below_4g, *ram_above_4g;
>      FWCfgState *fw_cfg;
>      PCMachineState *pcms = PC_MACHINE(machine);
> +    ram_addr_t offset;
>  
>      assert(machine->ram_size == below_4g_mem_size + above_4g_mem_size);
>  
> @@ -1339,6 +1341,8 @@ FWCfgState *pc_memory_init(MachineState *machine,
>          exit(EXIT_FAILURE);
>      }
>  
> +    offset = 0x100000000ULL + above_4g_mem_size;
> +
>      /* initialize hotplug memory address space */
>      if (guest_info->has_reserved_memory &&
>          (machine->ram_size < machine->maxram_size)) {
> @@ -1358,8 +1362,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>              exit(EXIT_FAILURE);
>          }
>  
> -        pcms->hotplug_memory.base =
> -            ROUND_UP(0x100000000ULL + above_4g_mem_size, 1ULL << 30);
> +        pcms->hotplug_memory.base = ROUND_UP(offset, 1ULL << 30);
>  
>          if (pcms->enforce_aligned_dimm) {
>              /* size hotplug region assuming 1G page max alignment per slot */
> @@ -1377,8 +1380,13 @@ FWCfgState *pc_memory_init(MachineState *machine,
>                             "hotplug-memory", hotplug_mem_size);
>          memory_region_add_subregion(system_memory, pcms->hotplug_memory.base,
>                                      &pcms->hotplug_memory.mr);
> +
> +        offset = pcms->hotplug_memory.base + hotplug_mem_size;
>      }
>  
> +     /* all the space left above 4G is reserved for NVDIMM. */
> +    pc_nvdimm_reserve_range(offset);
I'd drop 'offset' in this patch and just use:
  foo(pcms->hotplug_memory.base + hotplug_mem_size)

> +
>      /* Initialize PC system firmware */
>      pc_system_firmware_init(rom_memory, guest_info->isapc_ram_fw);
>  
> diff --git a/hw/mem/nvdimm/pc-nvdimm.c b/hw/mem/nvdimm/pc-nvdimm.c
> index a53d235..7a270a8 100644
> --- a/hw/mem/nvdimm/pc-nvdimm.c
> +++ b/hw/mem/nvdimm/pc-nvdimm.c
> @@ -24,6 +24,19 @@
>  
>  #include "hw/mem/pc-nvdimm.h"
>  
> +#define PAGE_SIZE      (1UL << 12)
> +
> +static struct nvdimms_info {
> +    ram_addr_t current_addr;
> +} nvdimms_info;
no globals please, so far it looks like pcms->hotplug_memory
so add asimmilar nvdimm_memory field to PCMachineState

> +
> +/* the address range [offset, ~0ULL) is reserved for NVDIMM. */
> +void pc_nvdimm_reserve_range(ram_addr_t offset)
do you plan to reuse this function, if not then just inline it at call site

> +{
> +    offset = ROUND_UP(offset, PAGE_SIZE);
I'd suggest round up to 1Gb as we do with mem hotplug

> +    nvdimms_info.current_addr = offset;
> +}
> +
>  static char *get_file(Object *obj, Error **errp)
>  {
>      PCNVDIMMDevice *nvdimm = PC_NVDIMM(obj);
> diff --git a/include/hw/mem/pc-nvdimm.h b/include/hw/mem/pc-nvdimm.h
> index 51152b8..8601e9b 100644
> --- a/include/hw/mem/pc-nvdimm.h
> +++ b/include/hw/mem/pc-nvdimm.h
> @@ -28,4 +28,5 @@ typedef struct PCNVDIMMDevice {
>  #define PC_NVDIMM(obj) \
>      OBJECT_CHECK(PCNVDIMMDevice, (obj), TYPE_PC_NVDIMM)
>  
> +void pc_nvdimm_reserve_range(ram_addr_t offset);
>  #endif

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Xiao Guangrong Sept. 6, 2015, 7:22 a.m. UTC | #7
On 09/04/2015 08:02 PM, Igor Mammedov wrote:
> On Fri, 14 Aug 2015 22:52:00 +0800
> Xiao Guangrong <guangrong.xiao@linux.intel.com> wrote:
>
>> NVDIMM reserves all the free range above 4G to do:
>> - Persistent Memory (PMEM) mapping
>> - implement NVDIMM ACPI device _DSM method
>>
>> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
>> ---
>>   hw/i386/pc.c               | 12 ++++++++++--
>>   hw/mem/nvdimm/pc-nvdimm.c  | 13 +++++++++++++
>>   include/hw/mem/pc-nvdimm.h |  1 +
>>   3 files changed, 24 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>> index 7661ea9..41af6ea 100644
>> --- a/hw/i386/pc.c
>> +++ b/hw/i386/pc.c
>> @@ -64,6 +64,7 @@
>>   #include "hw/pci/pci_host.h"
>>   #include "acpi-build.h"
>>   #include "hw/mem/pc-dimm.h"
>> +#include "hw/mem/pc-nvdimm.h"
>>   #include "qapi/visitor.h"
>>   #include "qapi-visit.h"
>>
>> @@ -1302,6 +1303,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>>       MemoryRegion *ram_below_4g, *ram_above_4g;
>>       FWCfgState *fw_cfg;
>>       PCMachineState *pcms = PC_MACHINE(machine);
>> +    ram_addr_t offset;
>>
>>       assert(machine->ram_size == below_4g_mem_size + above_4g_mem_size);
>>
>> @@ -1339,6 +1341,8 @@ FWCfgState *pc_memory_init(MachineState *machine,
>>           exit(EXIT_FAILURE);
>>       }
>>
>> +    offset = 0x100000000ULL + above_4g_mem_size;
>> +
>>       /* initialize hotplug memory address space */
>>       if (guest_info->has_reserved_memory &&
>>           (machine->ram_size < machine->maxram_size)) {
>> @@ -1358,8 +1362,7 @@ FWCfgState *pc_memory_init(MachineState *machine,
>>               exit(EXIT_FAILURE);
>>           }
>>
>> -        pcms->hotplug_memory.base =
>> -            ROUND_UP(0x100000000ULL + above_4g_mem_size, 1ULL << 30);
>> +        pcms->hotplug_memory.base = ROUND_UP(offset, 1ULL << 30);
>>
>>           if (pcms->enforce_aligned_dimm) {
>>               /* size hotplug region assuming 1G page max alignment per slot */
>> @@ -1377,8 +1380,13 @@ FWCfgState *pc_memory_init(MachineState *machine,
>>                              "hotplug-memory", hotplug_mem_size);
>>           memory_region_add_subregion(system_memory, pcms->hotplug_memory.base,
>>                                       &pcms->hotplug_memory.mr);
>> +
>> +        offset = pcms->hotplug_memory.base + hotplug_mem_size;
>>       }
>>
>> +     /* all the space left above 4G is reserved for NVDIMM. */
>> +    pc_nvdimm_reserve_range(offset);
> I'd drop 'offset' in this patch and just use:
>    foo(pcms->hotplug_memory.base + hotplug_mem_size)
>

That works only if hotplug is used... however we can enable nvdimm separately.

>> +
>>       /* Initialize PC system firmware */
>>       pc_system_firmware_init(rom_memory, guest_info->isapc_ram_fw);
>>
>> diff --git a/hw/mem/nvdimm/pc-nvdimm.c b/hw/mem/nvdimm/pc-nvdimm.c
>> index a53d235..7a270a8 100644
>> --- a/hw/mem/nvdimm/pc-nvdimm.c
>> +++ b/hw/mem/nvdimm/pc-nvdimm.c
>> @@ -24,6 +24,19 @@
>>
>>   #include "hw/mem/pc-nvdimm.h"
>>
>> +#define PAGE_SIZE      (1UL << 12)
>> +
>> +static struct nvdimms_info {
>> +    ram_addr_t current_addr;
>> +} nvdimms_info;
> no globals please, so far it looks like pcms->hotplug_memory
> so add asimmilar nvdimm_memory field to PCMachineState
>

Okay, it's good to me.

>> +
>> +/* the address range [offset, ~0ULL) is reserved for NVDIMM. */
>> +void pc_nvdimm_reserve_range(ram_addr_t offset)
> do you plan to reuse this function, if not then just inline it at call site

I prefer it as a inline function and move it to the nvdimm.h file since it's easier
to port it to other platforms - avoid to find the pieces of code related to nvdimm
in x86 arch and only needed to implement the functions in nvdimm.h.

>
>> +{
>> +    offset = ROUND_UP(offset, PAGE_SIZE);
> I'd suggest round up to 1Gb as we do with mem hotplug

Okay, good to me.

Really appreciate for all your time/comment in the whole patchset, Igor!
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diff mbox

Patch

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 7661ea9..41af6ea 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -64,6 +64,7 @@ 
 #include "hw/pci/pci_host.h"
 #include "acpi-build.h"
 #include "hw/mem/pc-dimm.h"
+#include "hw/mem/pc-nvdimm.h"
 #include "qapi/visitor.h"
 #include "qapi-visit.h"
 
@@ -1302,6 +1303,7 @@  FWCfgState *pc_memory_init(MachineState *machine,
     MemoryRegion *ram_below_4g, *ram_above_4g;
     FWCfgState *fw_cfg;
     PCMachineState *pcms = PC_MACHINE(machine);
+    ram_addr_t offset;
 
     assert(machine->ram_size == below_4g_mem_size + above_4g_mem_size);
 
@@ -1339,6 +1341,8 @@  FWCfgState *pc_memory_init(MachineState *machine,
         exit(EXIT_FAILURE);
     }
 
+    offset = 0x100000000ULL + above_4g_mem_size;
+
     /* initialize hotplug memory address space */
     if (guest_info->has_reserved_memory &&
         (machine->ram_size < machine->maxram_size)) {
@@ -1358,8 +1362,7 @@  FWCfgState *pc_memory_init(MachineState *machine,
             exit(EXIT_FAILURE);
         }
 
-        pcms->hotplug_memory.base =
-            ROUND_UP(0x100000000ULL + above_4g_mem_size, 1ULL << 30);
+        pcms->hotplug_memory.base = ROUND_UP(offset, 1ULL << 30);
 
         if (pcms->enforce_aligned_dimm) {
             /* size hotplug region assuming 1G page max alignment per slot */
@@ -1377,8 +1380,13 @@  FWCfgState *pc_memory_init(MachineState *machine,
                            "hotplug-memory", hotplug_mem_size);
         memory_region_add_subregion(system_memory, pcms->hotplug_memory.base,
                                     &pcms->hotplug_memory.mr);
+
+        offset = pcms->hotplug_memory.base + hotplug_mem_size;
     }
 
+     /* all the space left above 4G is reserved for NVDIMM. */
+    pc_nvdimm_reserve_range(offset);
+
     /* Initialize PC system firmware */
     pc_system_firmware_init(rom_memory, guest_info->isapc_ram_fw);
 
diff --git a/hw/mem/nvdimm/pc-nvdimm.c b/hw/mem/nvdimm/pc-nvdimm.c
index a53d235..7a270a8 100644
--- a/hw/mem/nvdimm/pc-nvdimm.c
+++ b/hw/mem/nvdimm/pc-nvdimm.c
@@ -24,6 +24,19 @@ 
 
 #include "hw/mem/pc-nvdimm.h"
 
+#define PAGE_SIZE      (1UL << 12)
+
+static struct nvdimms_info {
+    ram_addr_t current_addr;
+} nvdimms_info;
+
+/* the address range [offset, ~0ULL) is reserved for NVDIMM. */
+void pc_nvdimm_reserve_range(ram_addr_t offset)
+{
+    offset = ROUND_UP(offset, PAGE_SIZE);
+    nvdimms_info.current_addr = offset;
+}
+
 static char *get_file(Object *obj, Error **errp)
 {
     PCNVDIMMDevice *nvdimm = PC_NVDIMM(obj);
diff --git a/include/hw/mem/pc-nvdimm.h b/include/hw/mem/pc-nvdimm.h
index 51152b8..8601e9b 100644
--- a/include/hw/mem/pc-nvdimm.h
+++ b/include/hw/mem/pc-nvdimm.h
@@ -28,4 +28,5 @@  typedef struct PCNVDIMMDevice {
 #define PC_NVDIMM(obj) \
     OBJECT_CHECK(PCNVDIMMDevice, (obj), TYPE_PC_NVDIMM)
 
+void pc_nvdimm_reserve_range(ram_addr_t offset);
 #endif