From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43872) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vbbdn-0008Eu-Mf for qemu-devel@nongnu.org; Wed, 30 Oct 2013 15:41:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Vbbdf-0004CS-8j for qemu-devel@nongnu.org; Wed, 30 Oct 2013 15:41:19 -0400 Received: from mail-pd0-x230.google.com ([2607:f8b0:400e:c02::230]:65063) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vbbdf-0004CF-1p for qemu-devel@nongnu.org; Wed, 30 Oct 2013 15:41:11 -0400 Received: by mail-pd0-f176.google.com with SMTP id g10so1420229pdj.35 for ; Wed, 30 Oct 2013 12:41:09 -0700 (PDT) Date: Thu, 31 Oct 2013 04:41:05 +0900 Message-ID: <87zjpqsg1a.wl%morita.kazutaka@gmail.com> From: MORITA Kazutaka In-Reply-To: <1383035152-14924-3-git-send-email-namei.unix@gmail.com> References: <1383035152-14924-1-git-send-email-namei.unix@gmail.com> <1383035152-14924-3-git-send-email-namei.unix@gmail.com> MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII 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: Liu Yuan Cc: Kevin Wolf , sheepdog@lists.wpkg.org, qemu-devel@nongnu.org, Stefan Hajnoczi 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. Thanks, Kazutaka