From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50387) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtEwz-0006j8-VU for qemu-devel@nongnu.org; Mon, 02 Nov 2015 08:15:06 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZtEww-0000XR-Pa for qemu-devel@nongnu.org; Mon, 02 Nov 2015 08:15:05 -0500 Received: from mga09.intel.com ([134.134.136.24]:51579) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtEww-0000XC-JO for qemu-devel@nongnu.org; Mon, 02 Nov 2015 08:15:02 -0500 References: <1446455617-129562-1-git-send-email-guangrong.xiao@linux.intel.com> <1446455617-129562-21-git-send-email-guangrong.xiao@linux.intel.com> <563754D5.2060401@virtuozzo.com> From: Xiao Guangrong Message-ID: <56376042.4090002@linux.intel.com> Date: Mon, 2 Nov 2015 21:08:18 +0800 MIME-Version: 1.0 In-Reply-To: <563754D5.2060401@virtuozzo.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit 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: Vladimir Sementsov-Ogievskiy , 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 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 >> >> 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 You mean merger this patch with 19/35 (dimm: abstract dimm device from pc-dimm)? The 19/35 mostly ‘moves’ the things, this one changes the core logic, it is not a big deal. :D > >> 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. > Yup, this is a globally interface so i prefer to make a separate patch to do the cleanup after this patchset.