diff mbox

[07/17] qemu-img: always probe the input image for allocated sectors

Message ID 1372862071-28225-8-git-send-email-pbonzini@redhat.com
State New
Headers show

Commit Message

Paolo Bonzini July 3, 2013, 2:34 p.m. UTC 
qemu-img convert is assuming "that sectors which are unallocated in the input
image are present in both the output's and input's base images", but it is
only doing this if the output image is zero initialized.  And checking if
the output image is zero initialized does not make much sense if the
output image is copy-on-write.  Always do the test.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 qemu-img.c | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)
diff mbox

Patch

diff --git a/qemu-img.c b/qemu-img.c
index 857e2ca..eb2561f 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1476,21 +1476,19 @@  static int img_convert(int argc, char **argv)
                 n = bs_offset + bs_sectors - sector_num;
             }
 
-            if (has_zero_init) {
-                /* If the output image is being created as a copy on write image,
-                   assume that sectors which are unallocated in the input image
-                   are present in both the output's and input's base images (no
-                   need to copy them). */
-                if (out_baseimg) {
-                    if (!bdrv_is_allocated(bs[bs_i], sector_num - bs_offset,
-                                           n, &n1)) {
-                        sector_num += n1;
-                        continue;
-                    }
-                    /* The next 'n1' sectors are allocated in the input image. Copy
-                       only those as they may be followed by unallocated sectors. */
-                    n = n1;
+            /* If the output image is being created as a copy on write image,
+               assume that sectors which are unallocated in the input image
+               are present in both the output's and input's base images (no
+               need to copy them). */
+            if (out_baseimg) {
+                if (!bdrv_is_allocated(bs[bs_i], sector_num - bs_offset,
+                                       n, &n1)) {
+                    sector_num += n1;
+                    continue;
                 }
+                /* The next 'n1' sectors are allocated in the input image. Copy
+                   only those as they may be followed by unallocated sectors. */
+                n = n1;
             } else {
                 n1 = n;
             }