Re: [Qemu-devel] [PATCH 2/3] fw_cfg: add API to find FW cfg object

[Hu Tao]

On Thu, May 30, 2013 at 04:28:01PM +0300, Michael S. Tsirkin wrote:
> Remove some code duplication by adding a
> function to look up the fw cfg file.
> This way, we don't need to duplicate same strings everywhere.
> Use by both fw cfg and pvpanic device.
> 
> Signed-off-by: Michael S. Tsirkin <address@hidden>
> ---
>  hw/misc/pvpanic.c         |  2 +-
>  hw/nvram/fw_cfg.c         | 15 ++++++++++++---
>  include/hw/nvram/fw_cfg.h |  2 ++
>  3 files changed, 15 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/misc/pvpanic.c b/hw/misc/pvpanic.c
> index 1483f27..910e44f 100644
> --- a/hw/misc/pvpanic.c
> +++ b/hw/misc/pvpanic.c
> @@ -96,7 +96,7 @@ static int pvpanic_isa_initfn(ISADevice *dev)
>      isa_register_ioport(dev, &s->io, s->ioport);
>  
>      if (!port_configured) {
> -        fw_cfg = object_resolve_path("/machine/fw_cfg", NULL);
> +        fw_cfg = fw_cfg_find();
>          if (fw_cfg) {
>              fw_cfg_add_file(fw_cfg, "etc/pvpanic-port",
>                              g_memdup(&s->ioport, sizeof(s->ioport)),
> diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
> index 479113b..df3f089 100644
> --- a/hw/nvram/fw_cfg.c
> +++ b/hw/nvram/fw_cfg.c
> @@ -32,6 +32,9 @@
>  
>  #define FW_CFG_SIZE 2
>  #define FW_CFG_DATA_SIZE 1
> +#define TYPE_FW_CFG "fw_cfg"
> +#define FW_CFG_NAME "fw_cfg"
> +#define FW_CFG_PATH "/machine/" FW_CFG_NAME
>  
>  typedef struct FWCfgEntry {
>      uint32_t len;
> @@ -493,8 +496,8 @@ FWCfgState *fw_cfg_init(uint32_t ctl_port, uint32_t 
> data_port,
>  
>      s = DO_UPCAST(FWCfgState, busdev.qdev, dev);
>  
> -    if (!object_resolve_path("/machine/fw_cfg", NULL)) {
> -        object_property_add_child(qdev_get_machine(), "fw_cfg", OBJECT(s),
> +    if (!object_resolve_path(FW_CFG_PATH, NULL)) {
> +        object_property_add_child(qdev_get_machine(), FW_CFG_NAME, OBJECT(s),
>                                    NULL);
>      }
>  
> @@ -553,6 +556,12 @@ static Property fw_cfg_properties[] = {
>      DEFINE_PROP_END_OF_LIST(),
>  };
>  
> +FWCfgState *fw_cfg_find(void)
> +{
> +    return OBJECT_CHECK(FWCfgState, object_resolve_path(FW_CFG_PATH, NULL),
> +                        TYPE_FW_CFG);
> +}
> +
>  static void fw_cfg_class_init(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> @@ -566,7 +575,7 @@ static void fw_cfg_class_init(ObjectClass *klass, void 
> *data)
>  }
>  
>  static const TypeInfo fw_cfg_info = {
> -    .name          = "fw_cfg",
> +    .name          = TYPE_FW_CFG,
>      .parent        = TYPE_SYS_BUS_DEVICE,
>      .instance_size = sizeof(FWCfgState),
>      .class_init    = fw_cfg_class_init,
> diff --git a/include/hw/nvram/fw_cfg.h b/include/hw/nvram/fw_cfg.h
> index f37714e..f60dd67 100644
> --- a/include/hw/nvram/fw_cfg.h
> +++ b/include/hw/nvram/fw_cfg.h
> @@ -73,6 +73,8 @@ void fw_cfg_add_file(FWCfgState *s, const char *filename, 
> void *data,
>  FWCfgState *fw_cfg_init(uint32_t ctl_port, uint32_t data_port,
>                          hwaddr crl_addr, hwaddr data_addr);
>  
> +FWCfgState *fw_cfg_find(void);

How about fw_cfg_get()? It makes me more comfortable than fw_cfg_find().

> +
>  #endif /* NO_QEMU_PROTOS */
>  
>  #endif
> -- 
> MST
>