From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55105) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V06le-0001QP-Vb for qemu-devel@nongnu.org; Fri, 19 Jul 2013 05:14:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V06lc-00030l-If for qemu-devel@nongnu.org; Fri, 19 Jul 2013 05:14:26 -0400 Received: from mail-ea0-x22d.google.com ([2a00:1450:4013:c01::22d]:61591) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V06lc-00030M-CC for qemu-devel@nongnu.org; Fri, 19 Jul 2013 05:14:24 -0400 Received: by mail-ea0-f173.google.com with SMTP id g15so2266689eak.18 for ; Fri, 19 Jul 2013 02:14:23 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <51E90363.5090008@redhat.com> Date: Fri, 19 Jul 2013 11:14:11 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1373992168-26043-1-git-send-email-pbonzini@redhat.com> <1373992168-26043-11-git-send-email-pbonzini@redhat.com> <51E8DE2C.9@kamp.de> In-Reply-To: <51E8DE2C.9@kamp.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 10/17] block: define get_block_status return value List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Lieven Cc: famz@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com Il 19/07/2013 08:35, Peter Lieven ha scritto: > On 16.07.2013 18:29, Paolo Bonzini wrote: >> Define the return value of get_block_status. Bits 0, 1, 2 and 9-62 >> are valid; bit 63 (the sign bit) is reserved for errors. Bits 3-7 >> are left for future extensions. >> >> The return code is compatible with the old is_allocated API: returning >> just 0 or 1 (aka BDRV_BLOCK_DATA) will not cause any behavioral change >> in clients of is_allocated. We will return more precise information >> in the next patches. >> >> Signed-off-by: Paolo Bonzini >> --- >> v1->v2: improved comment >> >> block.c | 7 +++++-- >> include/block/block.h | 26 ++++++++++++++++++++++++++ >> 2 files changed, 31 insertions(+), 2 deletions(-) >> >> diff --git a/block.c b/block.c >> index 6e7a8a3..7ff0716 100644 >> --- a/block.c >> +++ b/block.c >> @@ -2990,7 +2990,7 @@ static int64_t coroutine_fn >> bdrv_co_get_block_status(BlockDriverState *bs, >> if (!bs->drv->bdrv_co_get_block_status) { >> *pnum = nb_sectors; >> - return 1; >> + return BDRV_BLOCK_DATA; >> } >> return bs->drv->bdrv_co_get_block_status(bs, sector_num, >> nb_sectors, pnum); >> @@ -3040,7 +3040,10 @@ int64_t bdrv_get_block_status(BlockDriverState >> *bs, int64_t sector_num, >> int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t >> sector_num, >> int nb_sectors, int *pnum) >> { >> - return bdrv_get_block_status(bs, sector_num, nb_sectors, pnum); >> + int64_t ret = bdrv_get_block_status(bs, sector_num, nb_sectors, >> pnum); > just stumbled about a question i have: > > isn't here a > > if (ret < 0) { > *pnum = 0; > return 0; > } > > missing? > > I was told that this is the expected return behaviour in the > error case of the old API. Earlier in the series this is made more reasonable (is_allocated can return errors), but indeed a if (ret < 0) { return ret; } is missing. I'll send a follow-up. Paolo