From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37392) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtE5g-0005jq-Uh for qemu-devel@nongnu.org; Mon, 02 Nov 2015 07:20:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZtE5d-0005JD-Nh for qemu-devel@nongnu.org; Mon, 02 Nov 2015 07:20:00 -0500 Received: from relay.parallels.com ([195.214.232.42]:45313) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtE5d-0005It-FX for qemu-devel@nongnu.org; Mon, 02 Nov 2015 07:19:57 -0500 Message-ID: <563754D5.2060401@virtuozzo.com> Date: Mon, 2 Nov 2015 15:19:33 +0300 From: Vladimir Sementsov-Ogievskiy MIME-Version: 1.0 References: <1446455617-129562-1-git-send-email-guangrong.xiao@linux.intel.com> <1446455617-129562-21-git-send-email-guangrong.xiao@linux.intel.com> In-Reply-To: <1446455617-129562-21-git-send-email-guangrong.xiao@linux.intel.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v7 20/35] dimm: get mapped memory region from DIMMDeviceClass->get_memory_region List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Xiao Guangrong , pbonzini@redhat.com, imammedo@redhat.com Cc: ehabkost@redhat.com, kvm@vger.kernel.org, mst@redhat.com, gleb@kernel.org, mtosatti@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com, dan.j.williams@intel.com, rth@twiddle.net 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 > > Signed-off-by: Xiao Guangrong > --- > hw/mem/dimm.c | 3 ++- > hw/mem/pc-dimm.c | 12 +++++++++++- > 2 files changed, 13 insertions(+), 2 deletions(-) > > diff --git a/hw/mem/dimm.c b/hw/mem/dimm.c > index 4a63409..498d380 100644 > --- a/hw/mem/dimm.c > +++ b/hw/mem/dimm.c > @@ -377,8 +377,9 @@ static void dimm_get_size(Object *obj, Visitor *v, void *opaque, > int64_t value; > MemoryRegion *mr; > DIMMDevice *dimm = DIMM(obj); > + DIMMDeviceClass *ddc = DIMM_GET_CLASS(obj); > > - mr = host_memory_backend_get_memory(dimm->hostmem, errp); > + mr = ddc->get_memory_region(dimm); > value = memory_region_size(mr); > > visit_type_int(v, &value, name, errp); > diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c > index 38323e9..e6b6a9f 100644 > --- a/hw/mem/pc-dimm.c > +++ b/hw/mem/pc-dimm.c > @@ -22,7 +22,17 @@ > > static MemoryRegion *pc_dimm_get_memory_region(DIMMDevice *dimm) > { > - return host_memory_backend_get_memory(dimm->hostmem, &error_abort); > + Error *local_err = NULL; > + MemoryRegion *mr; > + > + mr = host_memory_backend_get_memory(dimm->hostmem, &local_err); > + > + /* > + * plug a pc-dimm device whose backend memory was not properly > + * initialized? > + */ > + assert(!local_err && mr); > + return mr; > } this should squashed into previous patch, I think > > static void pc_dimm_class_init(ObjectClass *oc, void *data) I've discovered suddenly, that MemoryRegion * host_memory_backend_get_memory(HostMemoryBackend *backend, Error **errp) { return memory_region_size(&backend->mr) ? &backend->mr : NULL; } - it doesn't use errp at all. In my opinion, this should be fixed globally, by deleting useless parameter in separate patch. Or just squash your function into previous patch. -- Best regards, Vladimir * now, @virtuozzo.com instead of @parallels.com. Sorry for this inconvenience.