From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59658) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VbicL-00072V-Vv for qemu-devel@nongnu.org; Wed, 30 Oct 2013 23:08:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VbicB-0000ti-LS for qemu-devel@nongnu.org; Wed, 30 Oct 2013 23:08:17 -0400 Received: from mail-pd0-x22b.google.com ([2607:f8b0:400e:c02::22b]:59676) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VbicB-0000sT-DM for qemu-devel@nongnu.org; Wed, 30 Oct 2013 23:08:07 -0400 Received: by mail-pd0-f171.google.com with SMTP id w10so1862614pde.30 for ; Wed, 30 Oct 2013 20:08:06 -0700 (PDT) Date: Thu, 31 Oct 2013 11:07:56 +0800 From: Liu Yuan Message-ID: <20131031030755.GA3450@ubuntu-precise> References: <1383035152-14924-1-git-send-email-namei.unix@gmail.com> <1383035152-14924-3-git-send-email-namei.unix@gmail.com> <87zjpqsg1a.wl%morita.kazutaka@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87zjpqsg1a.wl%morita.kazutaka@gmail.com> Subject: Re: [Qemu-devel] [sheepdog] [PATCH v2 2/2] sheepdog: support user-defined redundancy option List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: MORITA Kazutaka Cc: Kevin Wolf , sheepdog@lists.wpkg.org, qemu-devel@nongnu.org, Stefan Hajnoczi On Thu, Oct 31, 2013 at 04:41:05AM +0900, MORITA Kazutaka wrote: > At Tue, 29 Oct 2013 16:25:52 +0800, > Liu Yuan wrote: > > > > Sheepdog support two kinds of redundancy, full replication and erasure coding. > > > > # create a fully replicated vdi with x copies > > -o redundancy=x (1 <= x <= SD_MAX_COPIES) > > > > # create a erasure coded vdi with x data strips and y parity strips > > -o redundancy=x:y (x must be one of {2,4,8,16} and 1 <= y < SD_EC_MAX_STRIP) > > > > E.g, to convert a vdi into sheepdog vdi 'test' with 8:3 erasure coding scheme > > > > $ qemu-img convert -o redundancy=8:3 linux-0.2.img sheepdog:test > > > > Cc: Kevin Wolf > > Cc: Stefan Hajnoczi > > Signed-off-by: Liu Yuan > > --- > > block/sheepdog.c | 78 ++++++++++++++++++++++++++++++++++++++++++++- > > include/block/block_int.h | 1 + > > 2 files changed, 78 insertions(+), 1 deletion(-) > > > > diff --git a/block/sheepdog.c b/block/sheepdog.c > > index e66d2f8..bd7cfd6 100644 > > --- a/block/sheepdog.c > > +++ b/block/sheepdog.c > > @@ -91,6 +91,14 @@ > > #define SD_NR_VDIS (1U << 24) > > #define SD_DATA_OBJ_SIZE (UINT64_C(1) << 22) > > #define SD_MAX_VDI_SIZE (SD_DATA_OBJ_SIZE * MAX_DATA_OBJS) > > +/* > > + * For erasure coding, we use at most SD_EC_MAX_STRIP for data strips and > > + * (SD_EC_MAX_STRIP - 1) for parity strips > > + * > > + * SD_MAX_COPIES is sum of number of dats trips and parity strips. > > + */ > > +#define SD_EC_MAX_STRIP 16 > > +#define SD_MAX_COPIES (SD_EC_MAX_STRIP * 2 - 1) > > > > #define SD_INODE_SIZE (sizeof(SheepdogInode)) > > #define CURRENT_VDI_ID 0 > > @@ -1446,6 +1454,65 @@ out: > > return ret; > > } > > > > +static int64_t is_numeric(const char *s) > > +{ > > + char *end; > > + return strtosz_suffix(s, &end, STRTOSZ_DEFSUFFIX_B); > > +} > > I think the type of the return value should be bool. > Actually I copied from cvtnum() it returns negative to indicate errors. Either way I found a bug in this version. I'll try another approach to test if it is numbers in next version. Thanks Yuan