On 11/03/2015 12:16 AM, Vladimir Sementsov-Ogievskiy wrote:
On 02.11.2015 18:06, Xiao Guangrong wrote:
On 11/02/2015 10:26 PM, Vladimir Sementsov-Ogievskiy wrote:
On 02.11.2015 16:08, Xiao Guangrong wrote:
On 11/02/2015 08:19 PM, Vladimir Sementsov-Ogievskiy wrote:
On 02.11.2015 12:13, Xiao Guangrong wrote:
Curretly, the memory region of backed memory is directly mapped to
guest's address space, however, it is not true for nvdimm device
This patch let dimm device realize this fact and use
DIMMDeviceClass->get_memory_region method to get the mapped memory
region
Current code did not check the return value of get_memory_region as it
assumed the backend memory of pc-dimm is always properly initialized,
we make get_memory_region internally catch the case if something is
wrong
but here you call not pc-dimm's get_memory_region, but common
ddc->get_memory_region, which may be
nvdimm or possibly other future dimm, so, why not check it here? And than
pc_dimm_get_memory_region
may be left untouched (error_abort is ok, because errp is unused).
Hmm, because 'here' is not the only place calling ->get_memory_region, this
method has
multiple callers:
$ git grep "\->get_memory_region"
hw/i386/pc.c: MemoryRegion *mr = ddc->get_memory_region(dimm);
hw/i386/pc.c: MemoryRegion *mr = ddc->get_memory_region(dimm);
hw/mem/dimm.c: mr = ddc->get_memory_region(dimm);
hw/mem/nvdimm.c: ddc->get_memory_region = nvdimm_get_memory_region;
hw/mem/pc-dimm.c: ddc->get_memory_region = pc_dimm_get_memory_region;
hw/ppc/spapr.c: MemoryRegion *mr = ddc->get_memory_region(dimm);
memory region validation is also done for NVDIMM in nvdimm device.
Ok, then it should be documented by a comment in dimm.h, where DIMMDeviceClass
is defined, that this
function should not fail
Okay, how about this comment:
/*
* get the memory region which will be mapped into guest's address
* space. It is called after dimm device realized so it is never
* failed.
*/
MemoryRegion *(*get_memory_region)(DIMMDevice *dimm);
