Re: [PATCH v5 02/79] machine: introduce memory-backend property

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 2/17/20 6:33 PM, Igor Mammedov wrote:
> Property will contain link to memory backend that will be
> used for backing initial RAM.
> Follow up commit will alias -mem-path and -mem-prealloc
> CLI options into memory backend options to make memory
> handling consistent (using only hostmem backend family
> for guest RAM allocation).
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
> v4:
>   * make property a string, instead of a link.
>     Fixes -M memory-backend=foo: foo not found error
>     since foo creation is delayed well beyond point
>     where machine's properties are set
> v3:
>   * rename property name from ram-memdev to memory-backend
>     (Paolo Bonzini <pbonzini@redhat.com>)
> 
> CC: ehabkost@redhat.com
> CC: pbonzini@redhat.com
> CC: pasic@linux.ibm.com
> ---
>   include/hw/boards.h |  2 ++
>   hw/core/machine.c   | 24 ++++++++++++++++++++++++
>   2 files changed, 26 insertions(+)
> 
> diff --git a/include/hw/boards.h b/include/hw/boards.h
> index fb1b43d5b9..7b4b6b79d7 100644
> --- a/include/hw/boards.h
> +++ b/include/hw/boards.h
> @@ -4,6 +4,7 @@
>   #define HW_BOARDS_H
>   
>   #include "exec/memory.h"
> +#include "sysemu/hostmem.h"
>   #include "sysemu/blockdev.h"
>   #include "sysemu/accel.h"
>   #include "qapi/qapi-types-machine.h"
> @@ -285,6 +286,7 @@ struct MachineState {
>       bool enforce_config_section;
>       bool enable_graphics;
>       char *memory_encryption;
> +    char *ram_memdev_id;
>       DeviceMemoryState *device_memory;
>   
>       ram_addr_t ram_size;
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index 84812a1d1c..1a6e485c87 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -508,6 +508,22 @@ static void validate_sysbus_device(SysBusDevice *sbdev, void *opaque)
>       }
>   }
>   
> +static char *machine_get_memdev(Object *obj, Error **errp)
> +{
> +    MachineState *ms = MACHINE(obj);
> +
> +    return g_strdup(ms->ram_memdev_id);
> +}
> +
> +static void machine_set_memdev(Object *obj, const char *value, Error **errp)
> +{
> +    MachineState *ms = MACHINE(obj);
> +
> +    g_free(ms->ram_memdev_id);
> +    ms->ram_memdev_id = g_strdup(value);
> +}
> +
> +
>   static void machine_init_notify(Notifier *notifier, void *data)
>   {
>       MachineState *machine = MACHINE(qdev_get_machine());
> @@ -889,6 +905,14 @@ static void machine_initfn(Object *obj)
>                                           "Table (HMAT)", NULL);
>       }
>   
> +    object_property_add_str(obj, "memory-backend",
> +                            machine_get_memdev, machine_set_memdev,
> +                            &error_abort);
> +    object_property_set_description(obj, "memory-backend",
> +                                    "Set RAM backend"
> +                                    "Valid value is ID of hostmem based backend",
> +                                     &error_abort);
> +
>       /* Register notifier when init is done for sysbus sanity checks */
>       ms->sysbus_notifier.notify = machine_init_notify;
>       qemu_add_machine_init_done_notifier(&ms->sysbus_notifier);
> 

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>