Re: [Qemu-devel] [PATCH] pc-dimm: use same mechanism for [get|set]_addr

[Igor Mammedov]

On Wed, 6 Feb 2019 23:55:15 +0000
Wei Yang <address@hidden> wrote:

> On Wed, Feb 06, 2019 at 12:59:49PM +0100, Igor Mammedov wrote:
> >On Fri,  1 Feb 2019 09:08:37 +0800
> >Wei Yang <address@hidden> wrote:
> >
> >> [get|set]_addr are two counterpart to access PCDIMMDevice.addr.
> >> 
> >> Since we have already set up a property PC_DIMM_ADDR_PROP for this
> >> field and use this mechanism in set_addr, it would be more proper to use
> >> the same mechanism in set_addr.
> >> 
> >> This patch uses object_property_get_uint() to replace the direct memory
> >> access to make [get|set]_addr with the same mechanism.
> >> 
> >> Signed-off-by: Wei Yang <address@hidden>
> >> ---
> >>  hw/mem/pc-dimm.c | 4 +---
> >>  1 file changed, 1 insertion(+), 3 deletions(-)
> >> 
> >> diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
> >> index 0c9b9e8292..c0658b9b88 100644
> >> --- a/hw/mem/pc-dimm.c
> >> +++ b/hw/mem/pc-dimm.c
> >> @@ -204,9 +204,7 @@ static MemoryRegion 
> >> *pc_dimm_get_memory_region(PCDIMMDevice *dimm, Error **errp)
> >>  
> >>  static uint64_t pc_dimm_md_get_addr(const MemoryDeviceState *md)
> >>  {
> >> -    const PCDIMMDevice *dimm = PC_DIMM(md);
> >> -
> >> -    return dimm->addr;
> >> +    return object_property_get_uint(OBJECT(md), PC_DIMM_ADDR_PROP, NULL);
> >it's not good to ignore errors
> >
> >s/NULL/error_abort/
> >
> >so we would notice if error ever happened.
> 
> You mean something like this?
> 
>       Error *err;
>       uint64_t addr;
> 
>       addr = object_property_get_uint(OBJECT(md), PC_DIMM_ADDR_PROP, &err);

see how error_abort is used in QEMU,
point is if there is a error that should never happen it is programming error so
QEMU should crash and we should fix it.

> 
>       if (err) {
>               warn_report_err(&err);
>               return 0;
>       }
> 
>       return addr;
> 
> >
> >>  }
> >>  
> >>  static void pc_dimm_md_set_addr(MemoryDeviceState *md, uint64_t addr,
> >
>