From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53975) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VKQb1-000762-3J for qemu-devel@nongnu.org; Fri, 13 Sep 2013 06:27:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VKQas-0003Sq-O8 for qemu-devel@nongnu.org; Fri, 13 Sep 2013 06:27:27 -0400 Received: from mx.ipv6.kamp.de ([2a02:248:0:51::16]:35010 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VKQas-0003Rj-86 for qemu-devel@nongnu.org; Fri, 13 Sep 2013 06:27:18 -0400 From: Peter Lieven Date: Fri, 13 Sep 2013 12:25:05 +0200 Message-Id: <1379067909-22984-9-git-send-email-pl@kamp.de> In-Reply-To: <1379067909-22984-1-git-send-email-pl@kamp.de> References: <1379067909-22984-1-git-send-email-pl@kamp.de> Subject: [Qemu-devel] [PATCH 08/12] qemu-img: conditionally zero out target on convert List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, ronniesahlberg@gmail.com, Peter Lieven , stefanha@redhat.com, anthony@codemonkey.ws, pbonzini@redhat.com if the target has_zero_init = 0, but supports efficiently writing zeroes by unmapping we call bdrv_zeroize to avoid fully allocating the target. this currently is designed especially for iscsi. Signed-off-by: Peter Lieven --- qemu-img.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/qemu-img.c b/qemu-img.c index 3e5e388..6eaddc6 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1354,7 +1354,8 @@ static int img_convert(int argc, char **argv) } } - flags = BDRV_O_RDWR; + flags = BDRV_O_RDWR | BDRV_O_UNMAP; + ret = bdrv_parse_cache_flags(cache, &flags); if (ret < 0) { error_report("Invalid cache option: %s", cache); @@ -1386,12 +1387,13 @@ static int img_convert(int argc, char **argv) } } + ret = bdrv_get_info(out_bs, &bdi); + if (ret < 0) { + error_report("could not get block driver info"); + goto out; + } + if (compress) { - ret = bdrv_get_info(out_bs, &bdi); - if (ret < 0) { - error_report("could not get block driver info"); - goto out; - } cluster_size = bdi.cluster_size; if (cluster_size <= 0 || cluster_size > IO_BUF_SIZE) { error_report("invalid cluster size"); @@ -1470,6 +1472,14 @@ static int img_convert(int argc, char **argv) } else { int has_zero_init = bdrv_has_zero_init(out_bs); + if (!has_zero_init && !out_baseimg && bdi.discard_write_zeroes) { + ret = bdrv_zeroize(out_bs, BDRV_REQ_MAY_UNMAP); + if (ret < 0) { + goto out; + } + has_zero_init = 1; + } + sector_num = 0; // total number of sectors converted so far nb_sectors = total_sectors - sector_num; if (nb_sectors != 0) { -- 1.7.9.5