From cf918fe08d1cf84f3825cea464c93278c647df52 Mon Sep 17 00:00:00 2001
Message-Id: <cf918fe08d1cf84f3825cea464c93278c647df52.1389014116.git.minovotn@redhat.com>
In-Reply-To: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com>
References: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com>
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 9 Dec 2013 14:09:09 +0100
Subject: [PATCH 21/50] qemu-img: add support for fully allocated images
RH-Author: Paolo Bonzini <pbonzini@redhat.com>
Message-id: <1386598178-11845-24-git-send-email-pbonzini@redhat.com>
Patchwork-id: 56060
O-Subject: [RHEL 7.0 qemu-kvm PATCH 23/52] qemu-img: add support for fully allocated images
Bugzilla: 1007815
RH-Acked-by: Jeffrey Cody <jcody@redhat.com>
RH-Acked-by: Fam Zheng <famz@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
From: Peter Lieven <pl@kamp.de>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
(cherry picked from commit 11b6699af59b8684128debacfc7c44cbaa6ac53b)
---
qemu-img.c | 10 +++++++---
qemu-img.texi | 6 ++++++
2 files changed, 13 insertions(+), 3 deletions(-)
Signed-off-by: Michal Novotny <minovotn@redhat.com>
---
qemu-img.c | 10 +++++++---
qemu-img.texi | 6 ++++++
2 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/qemu-img.c b/qemu-img.c
index fa0fd0e..dfd8a92 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -99,8 +99,12 @@ static void help(void)
" '-h' with or without a command shows this help and lists the supported formats\n"
" '-p' show progress of command (only certain commands)\n"
" '-q' use Quiet mode - do not print any output (except errors)\n"
- " '-S' indicates the consecutive number of bytes that must contain only zeros\n"
- " for qemu-img to create a sparse image during conversion\n"
+ " '-S' indicates the consecutive number of bytes (defaults to 4k) that must\n"
+ " contain only zeros for qemu-img to create a sparse image during\n"
+ " conversion. If the number of bytes is 0, the source will not be scanned for\n"
+ " unallocated or zero sectors, and the destination image will always be\n"
+ " fully allocated\n"
+ " images will always be fully allocated\n"
" '--output' takes the format in which the output must be done (human or json)\n"
" '-n' skips the target volume creation (useful if the volume is created\n"
" prior to running qemu-img)\n"
@@ -1463,7 +1467,7 @@ static int img_convert(int argc, char **argv)
/* signal EOF to align */
bdrv_write_compressed(out_bs, 0, NULL, 0);
} else {
- int has_zero_init = bdrv_has_zero_init(out_bs);
+ int has_zero_init = min_sparse ? bdrv_has_zero_init(out_bs) : 0;
sector_num = 0; // total number of sectors converted so far
nb_sectors = total_sectors - sector_num;
diff --git a/qemu-img.texi b/qemu-img.texi
index 43ee4eb..dc578bb 100644
--- a/qemu-img.texi
+++ b/qemu-img.texi
@@ -193,6 +193,12 @@ Image conversion is also useful to get smaller image when using a
growable format such as @code{qcow} or @code{cow}: the empty sectors
are detected and suppressed from the destination image.
+@var{sparse_size} indicates the consecutive number of bytes (defaults to 4k)
+that must contain only zeros for qemu-img to create a sparse image during
+conversion. If @var{sparse_size} is 0, the source will not be scanned for
+unallocated or zero sectors, and the destination image will always be
+fully allocated.
+
You can use the @var{backing_file} option to force the output image to be
created as a copy on write image of the specified base image; the
@var{backing_file} should have the same content as the input's base image,
--
1.7.11.7