From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:38828)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <afaerber@suse.de>) id 1UljN7-0000g9-4z
	for qemu-devel@nongnu.org; Sun, 09 Jun 2013 13:25:42 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <afaerber@suse.de>) id 1UljN5-0007Ru-Nz
	for qemu-devel@nongnu.org; Sun, 09 Jun 2013 13:25:40 -0400
Received: from cantor2.suse.de ([195.135.220.15]:41955 helo=mx2.suse.de)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <afaerber@suse.de>) id 1UljN4-0007Rg-RI
	for qemu-devel@nongnu.org; Sun, 09 Jun 2013 13:25:39 -0400
Message-ID: <51B4BA8C.3070601@suse.de>
Date: Sun, 09 Jun 2013 19:25:32 +0200
From: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= <afaerber@suse.de>
MIME-Version: 1.0
References: <1370794247-28267-1-git-send-email-afaerber@suse.de>
	<1370794247-28267-18-git-send-email-afaerber@suse.de>
	<CAFEAcA88A-J8FpEKg4ofsmB4rEGRKP8V5OasGZ7LM+_aARYpdQ@mail.gmail.com>
In-Reply-To: <CAFEAcA88A-J8FpEKg4ofsmB4rEGRKP8V5OasGZ7LM+_aARYpdQ@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Subject: Re: [Qemu-devel] [PATCH qom-cpu v4 17/18] memory_mapping: Use
 hwaddr type for MemoryMapping virt_addr field
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Peter Maydell <peter.maydell@linaro.org>
Cc: qiaonuohan@cn.fujitsu.com, qemu-devel@nongnu.org, lcapitulino@redhat.com

Am 09.06.2013 19:17, schrieb Peter Maydell:
> On 9 June 2013 17:10, Andreas F=C3=A4rber <afaerber@suse.de> wrote:
>> The memory mapping API uses hwaddr, so use it in the struct, too.
>> This avoids a header dependency on target_ulong type.
>=20
>> --- a/include/sysemu/memory_mapping.h
>> +++ b/include/sysemu/memory_mapping.h
>> @@ -20,7 +20,7 @@
>>  /* The physical and virtual address in the memory mapping are contigu=
ous. */
>>  typedef struct MemoryMapping {
>>      hwaddr phys_addr;
>> -    target_ulong virt_addr;
>> +    hwaddr virt_addr;
>>      ram_addr_t length;
>=20
> This seems kind of odd given that HACKING specifically
> says that target_ulong is for virtual addresses and hwaddr
> for physical addresses. And in fact all the places that call
> memory_mapping_list_add_merge_sorted() actually pass a
> target_ulong as the virt_addr parameter, so maybe what we
> should be fixing is the function prototype?

Maybe. The benefit with going with the overwhelming use of hwaddr is
that memory_mapping.o can be compiled once for all targets, saving
compilation time.

The benefit of target_ulong would be saving a few bytes for 32-bit
targets at runtime.

> Incidentally that use of ram_addr_t for length looks
> kind of suspicious to me; it should probably be a hwaddr.

Looking at it strictly from a CPU and build perspective I'll happily
leave further code cleanups to someone else. :) Somewhere there's also a
misspelling of "memory" left to fix.

Andreas

--=20
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=C3=BCrnberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imend=C3=B6rffer; HRB 16746 AG N=C3=BC=
rnberg