Re: [PATCH v8 08/11] i386/pc: factor out device_memory base/size to helper

[Joao Martins]

On 7/18/22 14:03, Igor Mammedov wrote:
> On Fri, 15 Jul 2022 18:16:25 +0100
> Joao Martins <joao.m.martins@oracle.com> wrote:
> 
>> Move obtaining hole64_start from device_memory memory region base/size
>> into an helper alongside correspondent getters in pc_memory_init() when
>> the hotplug range is unitialized. While doing that remove the memory
>> region based logic from this newly added helper.
>>
>> This is the final step that allows pc_pci_hole64_start() to be callable
>> at the beginning of pc_memory_init() before any memory regions are
>> initialized.
>>
>> Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
>> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
> 
> Acked-by: Igor Mammedov <imammedo@redhat.com>
> 
Thanks!
>> ---
>>  hw/i386/pc.c | 47 ++++++++++++++++++++++++++++++++---------------
>>  1 file changed, 32 insertions(+), 15 deletions(-)
>>
>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>> index c654be6cf0bd..cda435e3baeb 100644
>> --- a/hw/i386/pc.c
>> +++ b/hw/i386/pc.c
>> @@ -825,15 +825,37 @@ static hwaddr pc_above_4g_end(PCMachineState *pcms)
>>      return x86ms->above_4g_mem_start + x86ms->above_4g_mem_size;
>>  }
>>  
>> -static uint64_t pc_get_cxl_range_start(PCMachineState *pcms)
>> +static void pc_get_device_memory_range(PCMachineState *pcms,
>> +                                       hwaddr *base,
>> +                                       ram_addr_t *device_mem_size)
>>  {
>>      PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
>>      MachineState *machine = MACHINE(pcms);
>> +    ram_addr_t size;
>> +    hwaddr addr;
>> +
>> +    size = machine->maxram_size - machine->ram_size;
>> +    addr = ROUND_UP(pc_above_4g_end(pcms), 1 * GiB);
>> +
>> +    if (pcmc->enforce_aligned_dimm) {
>> +        /* size device region assuming 1G page max alignment per slot */
>> +        size += (1 * GiB) * machine->ram_slots;
>> +    }
>> +
>> +    *base = addr;
>> +    *device_mem_size = size;
>> +}
>> +
>> +
> 
> stray newline
> 
I'll remove it in the v9 respin.

>> +static uint64_t pc_get_cxl_range_start(PCMachineState *pcms)
>> +{
>> +    PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
>>      hwaddr cxl_base;
>> +    ram_addr_t size;
>>  
>> -    if (pcmc->has_reserved_memory && machine->device_memory->base) {
>> -        cxl_base = machine->device_memory->base
>> -            + memory_region_size(&machine->device_memory->mr);
>> +    if (pcmc->has_reserved_memory) {
>> +        pc_get_device_memory_range(pcms, &cxl_base, &size);
>> +        cxl_base += size;
>>      } else {
>>          cxl_base = pc_above_4g_end(pcms);
>>      }
>> @@ -920,7 +942,7 @@ void pc_memory_init(PCMachineState *pcms,
>>      /* initialize device memory address space */
>>      if (pcmc->has_reserved_memory &&
>>          (machine->ram_size < machine->maxram_size)) {
>> -        ram_addr_t device_mem_size = machine->maxram_size - 
>> machine->ram_size;
>> +        ram_addr_t device_mem_size;
>>  
>>          if (machine->ram_slots > ACPI_MAX_RAM_SLOTS) {
>>              error_report("unsupported amount of memory slots: %"PRIu64,
>> @@ -935,13 +957,7 @@ void pc_memory_init(PCMachineState *pcms,
>>              exit(EXIT_FAILURE);
>>          }
>>  
>> -        machine->device_memory->base =
>> -            ROUND_UP(pc_above_4g_end(pcms), 1 * GiB);
>> -
>> -        if (pcmc->enforce_aligned_dimm) {
>> -            /* size device region assuming 1G page max alignment per slot */
>> -            device_mem_size += (1 * GiB) * machine->ram_slots;
>> -        }
>> +        pc_get_device_memory_range(pcms, &machine->device_memory->base, 
>> &device_mem_size);
>>  
>>          if ((machine->device_memory->base + device_mem_size) <
>>              device_mem_size) {
>> @@ -1046,13 +1062,14 @@ uint64_t pc_pci_hole64_start(void)
>>      PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
>>      MachineState *ms = MACHINE(pcms);
>>      uint64_t hole64_start = 0;
>> +    ram_addr_t size = 0;
>>  
>>      if (pcms->cxl_devices_state.is_enabled) {
>>          hole64_start = pc_get_cxl_range_end(pcms);
>> -    } else if (pcmc->has_reserved_memory && ms->device_memory->base) {
>> -        hole64_start = ms->device_memory->base;
>> +    } else if (pcmc->has_reserved_memory && (ms->ram_size < 
>> ms->maxram_size)) {
>> +        pc_get_device_memory_range(pcms, &hole64_start, &size);
>>          if (!pcmc->broken_reserved_end) {
>> -            hole64_start += memory_region_size(&ms->device_memory->mr);
>> +            hole64_start += size;
>>          }
>>      } else {
>>          hole64_start = pc_above_4g_end(pcms);
>